An opportunistic viral infection of the central nervous system associated with conditions that impair cell-mediated immunity (e.g., ACQUIRED IMMUNODEFICIENCY SYNDROME and other IMMUNOLOGIC DEFICIENCY SYNDROMES; HEMATOLOGIC NEOPLASMS; IMMUNOSUPPRESSION; and COLLAGEN DISEASES). The causative organism is JC Polyomavirus (JC VIRUS) which primarily affects oligodendrocytes, resulting in multiple areas of demyelination. Clinical manifestations include DEMENTIA; ATAXIA; visual disturbances; and other focal neurologic deficits, generally progressing to a vegetative state within 6 months. (From Joynt, Clinical Neurology, 1996, Ch26, pp36-7)
A species of POLYOMAVIRUS, originally isolated from the brain of a patient with progressive multifocal leukoencephalopathy. The patient's initials J.C. gave the virus its name. Infection is not accompanied by any apparent illness but serious demyelinating disease can appear later, probably following reactivation of latent virus.
Any of various diseases affecting the white matter of the central nervous system.
A familial, cerebral arteriopathy mapped to chromosome 19q12, and characterized by the presence of granular deposits in small CEREBRAL ARTERIES producing ischemic STROKE; PSEUDOBULBAR PALSY; and multiple subcortical infarcts (CEREBRAL INFARCTION). CADASIL is an acronym for Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy. CADASIL differs from BINSWANGER DISEASE by the presence of MIGRAINE WITH AURA and usually by the lack of history of arterial HYPERTENSION. (From Bradley et al, Neurology in Clinical Practice, 2000, p1146)
Infections with POLYOMAVIRUS, which are often cultured from the urine of kidney transplant patients. Excretion of BK VIRUS is associated with ureteral strictures and CYSTITIS, and that of JC VIRUS with progressive multifocal leukoencephalopathy (LEUKOENCEPHALOPATHY, PROGRESSIVE MULTIFOCAL).
A condition that is characterized by HEADACHE; SEIZURES; and visual loss with edema in the posterior aspects of the CEREBRAL HEMISPHERES, such as the BRAIN STEM. Generally, lesions involve the white matter (nerve fibers) but occasionally the grey matter (nerve cell bodies).
Loss of higher cortical functions with retained awareness due to multiple cortical or subcortical CEREBRAL INFARCTION. Memory, judgment, attention span, and impulse control are often impaired, and may be accompanied by PSEUDOBULBAR PALSY; HEMIPARESIS; reflex abnormalities, and other signs of localized neurologic dysfunction. (From Adams et al., Principles of Neurology, 6th ed, p1060)
A watery fluid that is continuously produced in the CHOROID PLEXUS and circulates around the surface of the BRAIN; SPINAL CORD; and in the CEREBRAL VENTRICLES.
Reproducible depletion of CD4+ lymphocytes below 300 per cubic millimeter in the absence of HIV infection or other known causes of immunodeficiency. This is a rare, heterogeneous syndrome and does not appear to be caused by a transmissible agent.
A tetracyclic compound with antidepressant effects. It may cause drowsiness and hematological problems. Its mechanism of therapeutic action is not well understood, although it apparently blocks alpha-adrenergic, histamine H1, and some types of serotonin receptors.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
Infections produced by oncogenic viruses. The infections caused by DNA viruses are less numerous but more diverse than those caused by the RNA oncogenic viruses.
Pathologic conditions affecting the BRAIN, which is composed of the intracranial components of the CENTRAL NERVOUS SYSTEM. This includes (but is not limited to) the CEREBRAL CORTEX; intracranial white matter; BASAL GANGLIA; THALAMUS; HYPOTHALAMUS; BRAIN STEM; and CEREBELLUM.
Opportunistic infections found in patients who test positive for human immunodeficiency virus (HIV). The most common include PNEUMOCYSTIS PNEUMONIA, Kaposi's sarcoma, cryptosporidiosis, herpes simplex, toxoplasmosis, cryptococcosis, and infections with Mycobacterium avium complex, Microsporidium, and Cytomegalovirus.
Death resulting from the presence of a disease in an individual, as shown by a single case report or a limited number of patients. This should be differentiated from DEATH, the physiological cessation of life and from MORTALITY, an epidemiological or statistical concept.
Deoxyribonucleic acid that makes up the genetic material of viruses.
Exuberant inflammatory response towards previously undiagnosed or incubating opportunistic pathogens. It is frequently seen in AIDS patients following HAART.
Inherited conditions characterized by a loss of MYELIN in the central nervous system.
A genus of potentially oncogenic viruses of the family POLYOMAVIRIDAE. These viruses are normally present in their natural hosts as latent infections. The virus is oncogenic in hosts different from the species of origin.
A species of POLYOMAVIRUS apparently infecting over 90% of children but not clearly associated with any clinical illness in childhood. The virus remains latent in the body throughout life and can be reactivated under certain circumstances.
An integrin alpha subunit that is unique in that it does not contain an I domain, and its proteolytic cleavage site is near the middle of the extracellular portion of the polypeptide rather than close to the membrane as in other integrin alpha subunits.
Congenital or acquired cysts of the brain, spinal cord, or meninges which may remain stable in size or undergo progressive enlargement.
A syndrome characterized by a silent and inert state without voluntary motor activity despite preserved sensorimotor pathways and vigilance. Bilateral FRONTAL LOBE dysfunction involving the anterior cingulate gyrus and related brain injuries are associated with this condition. This may result in impaired abilities to communicate and initiate motor activities. (From Adams et al., Principles of Neurology, 6th ed, p348; Fortschr Neurol Psychiatr 1995 Feb;63(2):59-67)
A neurologic condition associated with the ACQUIRED IMMUNODEFICIENCY SYNDROME and characterized by impaired concentration and memory, slowness of hand movements, ATAXIA, incontinence, apathy, and gait difficulties associated with HIV-1 viral infection of the central nervous system. Pathologic examination of the brain reveals white matter rarefaction, perivascular infiltrates of lymphocytes, foamy macrophages, and multinucleated giant cells. (From Adams et al., Principles of Neurology, 6th ed, pp760-1; N Engl J Med, 1995 Apr 6;332(14):934-40)
A specific HLA-B surface antigen subtype. Members of this subtype contain alpha chains that are encoded by the HLA-B*18 allele family.
An infection caused by an organism which becomes pathogenic under certain conditions, e.g., during immunosuppression.
Diseases characterized by loss or dysfunction of myelin in the central or peripheral nervous system.
A disorder of cognition characterized by the tetrad of finger agnosia, dysgraphia, DYSCALCULIA, and right-left disorientation. The syndrome may be developmental or acquired. Acquired Gerstmann syndrome is associated with lesions in the dominant (usually left) PARIETAL LOBE which involve the angular gyrus or subjacent white matter. (From Adams et al., Principles of Neurology, 6th ed, p457)
The most common clinical variant of MULTIPLE SCLEROSIS, characterized by recurrent acute exacerbations of neurologic dysfunction followed by partial or complete recovery. Common clinical manifestations include loss of visual (see OPTIC NEURITIS), motor, sensory, or bladder function. Acute episodes of demyelination may occur at any site in the central nervous system, and commonly involve the optic nerves, spinal cord, brain stem, and cerebellum. (Adams et al., Principles of Neurology, 6th ed, pp903-914)
Antibodies from non-human species whose protein sequences have been modified to make them nearly identical with human antibodies. If the constant region and part of the variable region are replaced, they are called humanized. If only the constant region is modified they are called chimeric. INN names for humanized antibodies end in -zumab.
Proteins that form the CAPSID of VIRUSES.
A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation.
An acquired defect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/microliter or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms. Clinical manifestations also include emaciation (wasting) and dementia. These elements reflect criteria for AIDS as defined by the CDC in 1993.
An autoimmune disorder mainly affecting young adults and characterized by destruction of myelin in the central nervous system. Pathologic findings include multiple sharply demarcated areas of demyelination throughout the white matter of the central nervous system. Clinical manifestations include visual loss, extra-ocular movement disorders, paresthesias, loss of sensation, weakness, dysarthria, spasticity, ataxia, and bladder dysfunction. The usual pattern is one of recurrent attacks followed by partial recovery (see MULTIPLE SCLEROSIS, RELAPSING-REMITTING), but acute fulminating and chronic progressive forms (see MULTIPLE SCLEROSIS, CHRONIC PROGRESSIVE) also occur. (Adams et al., Principles of Neurology, 6th ed, p903)
Brain dysfunction or damage resulting from sustained MALIGNANT HYPERTENSION. When BLOOD PRESSURE exceeds the limits of cerebral autoregulation, cerebral blood flow is impaired (BRAIN ISCHEMIA). Clinical manifestations include HEADACHE; NAUSEA; VOMITING; SEIZURES; altered mental status (in some cases progressing to COMA); PAPILLEDEMA; and RETINAL HEMORRHAGE.
The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the BLOOD-BRAIN BARRIER and BLOOD-RETINAL BARRIER, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear.
A class of large neuroglial (macroglial) cells in the central nervous system. Oligodendroglia may be called interfascicular, perivascular, or perineuronal (not the same as SATELLITE CELLS, PERINEURONAL of GANGLIA) according to their location. They form the insulating MYELIN SHEATH of axons in the central nervous system.
Carbon-containing phosphonic acid compounds. Included under this heading are compounds that have carbon bound to either OXYGEN atom or the PHOSPHOROUS atom of the (P=O)O2 structure.
Those proteins recognized by antibodies from serum of animals bearing tumors induced by viruses; these proteins are presumably coded for by the nucleic acids of the same viruses that caused the neoplastic transformation.
An imprecise term referring to dementia associated with CEREBROVASCULAR DISORDERS, including CEREBRAL INFARCTION (single or multiple), and conditions associated with chronic BRAIN ISCHEMIA. Diffuse, cortical, and subcortical subtypes have been described. (From Gerontol Geriatr 1998 Feb;31(1):36-44)
A phospholipid-interacting antimalarial drug (ANTIMALARIALS). It is very effective against PLASMODIUM FALCIPARUM with very few side effects.
Diseases of any component of the brain (including the cerebral hemispheres, diencephalon, brain stem, and cerebellum) or the spinal cord.
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
A pyrimidine base that is a fundamental unit of nucleic acids.
Polyomavirus antigens which cause infection and cellular transformation. The large T antigen is necessary for the initiation of viral DNA synthesis, repression of transcription of the early region and is responsible in conjunction with the middle T antigen for the transformation of primary cells. Small T antigen is necessary for the completion of the productive infection cycle.
Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the URETHRA.
A pyrimidine nucleoside analog that is used mainly in the treatment of leukemia, especially acute non-lymphoblastic leukemia. Cytarabine is an antimetabolite antineoplastic agent that inhibits the synthesis of DNA. Its actions are specific for the S phase of the cell cycle. It also has antiviral and immunosuppressant properties. (From Martindale, The Extra Pharmacopoeia, 30th ed, p472)
Inflammation of brain parenchymal tissue as a result of viral infection. Encephalitis may occur as primary or secondary manifestation of TOGAVIRIDAE INFECTIONS; HERPESVIRIDAE INFECTIONS; ADENOVIRIDAE INFECTIONS; FLAVIVIRIDAE INFECTIONS; BUNYAVIRIDAE INFECTIONS; PICORNAVIRIDAE INFECTIONS; PARAMYXOVIRIDAE INFECTIONS; ORTHOMYXOVIRIDAE INFECTIONS; RETROVIRIDAE INFECTIONS; and ARENAVIRIDAE INFECTIONS.
Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).
The mechanism by which latent viruses, such as genetically transmitted tumor viruses (PROVIRUSES) or PROPHAGES of lysogenic bacteria, are induced to replicate and then released as infectious viruses. It may be effected by various endogenous and exogenous stimuli, including B-cell LIPOPOLYSACCHARIDES, glucocorticoid hormones, halogenated pyrimidines, IONIZING RADIATION, ultraviolet light, and superinfecting viruses.
The ordered rearrangement of gene regions by DNA recombination such as that which occurs normally during development.
A family of conserved cell surface receptors that contain EPIDERMAL GROWTH FACTOR repeats in their extracellular domain and ANKYRIN repeats in their cytoplasmic domains. The cytoplasmic domain of notch receptors is released upon ligand binding and translocates to the CELL NUCLEUS where it acts as transcription factor.
Drug regimens, for patients with HIV INFECTIONS, that aggressively suppress HIV replication. The regimens usually involve administration of three or more different drugs including a protease inhibitor.
Antibodies obtained from a single clone of cells grown in mice or rats.
Pathogenic infections of the brain, spinal cord, and meninges. DNA VIRUS INFECTIONS; RNA VIRUS INFECTIONS; BACTERIAL INFECTIONS; MYCOPLASMA INFECTIONS; SPIROCHAETALES INFECTIONS; fungal infections; PROTOZOAN INFECTIONS; HELMINTHIASIS; and PRION DISEASES may involve the central nervous system as a primary or secondary process.
Antibodies produced by a single clone of cells.
Agents that suppress immune function by one of several mechanisms of action. Classical cytotoxic immunosuppressants act by inhibiting DNA synthesis. Others may act through activation of T-CELLS or by inhibiting the activation of HELPER CELLS. While immunosuppression has been brought about in the past primarily to prevent rejection of transplanted organs, new applications involving mediation of the effects of INTERLEUKINS and other CYTOKINES are emerging.
A broad category of viral proteins that play indirect roles in the biological processes and activities of viruses. Included here are proteins that either regulate the expression of viral genes or are involved in modifying host cell functions. Many of the proteins in this category serve multiple functions.
The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A species of POLYOMAVIRUS originally isolated from Rhesus monkey kidney tissue. It produces malignancy in human and newborn hamster kidney cell cultures.
Removal and pathologic examination of specimens in the form of small pieces of tissue from the living body.
Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses.
Agents used in the prophylaxis or therapy of VIRUS DISEASES. Some of the ways they may act include preventing viral replication by inhibiting viral DNA polymerase; binding to specific cell-surface receptors and inhibiting viral penetration or uncoating; inhibiting viral protein synthesis; or blocking late stages of virus assembly.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Infections of the BRAIN caused by the protozoan TOXOPLASMA gondii that primarily arise in individuals with IMMUNOLOGIC DEFICIENCY SYNDROMES (see also AIDS-RELATED OPPORTUNISTIC INFECTIONS). The infection may involve the brain diffusely or form discrete abscesses. Clinical manifestations include SEIZURES, altered mentation, headache, focal neurologic deficits, and INTRACRANIAL HYPERTENSION. (From Joynt, Clinical Neurology, 1998, Ch27, pp41-3)
Nucleic acid sequences involved in regulating the expression of genes.
The number of CD4-POSITIVE T-LYMPHOCYTES per unit volume of BLOOD. Determination requires the use of a fluorescence-activated flow cytometer.

Association of simian virus 40 with a central nervous system lesion distinct from progressive multifocal leukoencephalopathy in macaques with AIDS. (1/318)

The primate polyomavirus SV40 is known to cause interstitial nephritis in primary infections and progressive multifocal leukoencephalopathy (PML) upon reactivation of a latent infection in SIV-infected macaques. We now describe a second central nervous system manifestation of SV40: a meningoencephalitis affecting cerebral gray matter, without demyelination, distinct from PML. Meningoencephalitis appears also to be a primary manifestation of SV40 infection and can be seen in conjunction with SV40-induced interstitial nephritis and pneumonitis. The difference in the lesions of meningoencephalitis and PML does not appear to be due to cellular tropism, as both oligodendrocytes and astrocytes are infected in PML and meningoencephalitis, as determined by in situ hybridization or immunohistochemistry for SV40 coupled with immunohistochemistry for cellular determinants. This is further supported by examination of SV40 nucleic acid sequences from the ori-enhancer and large-T-antigen regions, which reveals no tissue-or lesion-specific variation in SV40 sequences.  (+info)

Immunohistochemical detection of JC virus in nontumorous renal tissue of a patient with renal cancer but without progressive multifocal leukoencephalopathy. (2/318)

We performed immunohistochemical staining on the nontumorous renal tissue of 45 patients with renal cancer but without progressive multifocal encephalopathy using JCV-specific antibody. For one patient we found positive staining of the nuclei of the renal collecting ducts. Immunoelectron microscopic examination of the positive cell nuclei revealed electron-dense polyomavirus-like particles.  (+info)

Progressive multifocal leukoencephalopathy after autologous bone marrow transplantation and alpha-interferon immunotherapy. (3/318)

A patient with a stage IV mantle cell lymphoma (according to the REAL classification) was treated with high-dose chemotherapy and autologous bone marrow transplantation. One year later while on alpha-interferon immunotherapy she suffered from progressive loss of short-term memory and reported difficulties in recognizing objects. Magnetic resonance imaging (MRI) showed a vast ring-enhancing lesion of the left postcentral parietal area. Serial stereotactic biopsies disclosed progressive multifocal leukoencephalopathy without JC-virus in the cerebrospinal fluid. Therapy with subcutaneous interleukin-2 (IL-2) every other day and intrathecal cytarabine once a week was started. After 4 weeks the patient refused further treatment. Nevertheless her condition improved over the next 8 months and MRI scans showed a marked improvement in the lesions.  (+info)

Progressive multifocal leucoencephalopathy with peripheral demyelinating neuropathy after autologous bone marrow transplantation for acute myeloblastic leukemia (FAB5). (4/318)

Progressive multifocal leucoencephalopathy is an opportunistic JC virus-related pathology occurring in immunocompromised patients. We report a case of severe cellular immunodeficiency in a patient who underwent autologous bone marrow transplantation for acute myeloblastic leukemia, and who subsequently developed progressive multifocal leucoencephalopathy, an unusual pathology in this context. Progressive multifocal leucoencephalopathy was preceded by a peripheral demyelinating neuropathy. We discuss the possible link between these two neuropathies, the possible aggravation or activation from CMV infection, as well as the possible contribution of bone marrow purging in the resultant cellular immunodeficiency.  (+info)

Clinical and virological monitoring during treatment with intrathecal cytarabine in patients with AIDS-associated progressive multifocal leukoencephalopathy. (5/318)

We describe the clinical and virological outcome of human immunodeficiency virus-infected patients with progressive multifocal leukoencephalopathy (PML) treated with cytarabine. Twenty-seven patients received intrathecal cytarabine, 5 received concomitant intravenous cytarabine, and 20 received concomitant antiretroviral therapy. The median baseline CD4+ cell count was 28/mm3. After 4 weeks, 4 (19%) of 21 evaluable patients had stable disease, whereas the others progressed. The median survival from diagnosis and from onset was 66 and 128 days, respectively. Patients with Karnofsky scores of >50 and those previously taking antiretroviral medications had a higher probability of survival 3 months after diagnosis (P = .003 and P = .05, respectively). Overall, after 4 weeks, median JC virus load in CSF increased by 0.7 log10 copies/mL from baseline (P = NS). The mean JC virus load at 4 weeks was lower in patients with stable disease than in progressors (3.47 vs. 4.47 log10 copies/mL; P = .027). JC virus became undetectable in the only patient who had a long-term stable condition. The concentration of JC virus in CSF showed a correlation with clinical outcome.  (+info)

Proton magnetic resonance spectroscopy pattern of progressive multifocal leukoencephalopathy in AIDS. (6/318)

The objective was to determine whether the use of intermediate echo times (135 ms) in proton magnetic resonance spectroscopy (1H-MRS) detects a homogenous pattern in progressive multifocal leukoencephalopathy (PML) in HIV-1 infected people, and to confirm the results of previous studies. Six patients infected with HIV-1, with PML established by biopsy, and six healthy age and sex matched volunteers were evaluated to define their spectroscopic pattern. 1H-MRS spectra performed at 1.5 T were obtained with the STEAM sequence: TE/TM/TR, 20 ms/13.7 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (STEAM-20) and with the PRESS sequence; TE/TR, 135 ms/2000 ms; 2500 Hz, size 2048 points, 256 acquisitions (PRESS-135). A single voxel was placed on the lesions and on the parieto-occipital white matter of controls. The peaks of N-acetylaspartate (NAA), choline (Cho), myoinositol (mI), lactate, and lipids were considered, and the results were expressed using creatine as reference. Spectra of PML lesions were characterised by significantly reduced NAA, lactate presence, and by significantly increased Cho and lipids compared with control group values. These results indicate that 1H-MRS detects a homogenous pattern in PML lesions. Recent studies, together with this, suggest that 1H-MRS may help in the diagnostic approach to patients with suspected PML lesions associated with AIDS.  (+info)

Archetypal and rearranged sequences of human polyomavirus JC transcription control region in peripheral blood leukocytes and in cerebrospinal fluid. (7/318)

Two forms of human polyomavirus JC (JCV) genome are known based upon the structure of the transcriptional control region (TCR) of the virus: the archetypal form, which is commonly detected in urine, and the rearranged form, which was first detected in brain tissue from progressive multifocal leukoencephalopathy (PML) patients. The latter actually includes a group of TCR variants that, relative to the former, are characterized by various deletions and/or duplications. The aim of this study was to establish whether or not a correlation exists among the TCR type, the spreading of the virus within the host and its ability to cause PML. JCV TCR sequences from peripheral blood leukocytes (PBL) and cerebrospinal fluid (CSF) obtained from various groups of patients were compared. JCV with archetypal TCR was detected in CSF and PBL specimens from patients without neurological disorders or who eventually received a diagnosis of a non-PML neurological disorder. Rearranged TCR sequences were detected in all the CSF and PBL specimens from PML patients. The high similarity observed between the TCR structure detected in PBL and CSF specimens from individual patients could strengthen the hypothesis that PBL has a role in spreading JCV to the brain. Moreover, heterogeneous TCR patterns have been shown in individual PBL specimens from PML patients. This supports the hypothesis that, in PBL, JCV may replicate and undergo rearrangements of the TCR. The detection of JCV DNA by PCR in CSF independently from PML, although rare, could suggest that this assay is not sufficient for a virological diagnosis of PML. Further studies are required to assess the usefulness of quantitative assays or TCR typing in combination with PCR for diagnostic purposes.  (+info)

Progressive multifocal leukoencephalopathy in a patient with acquired immunodeficiency syndrome (AIDS) manifesting Gerstmann's syndrome. (8/318)

We reported a case of acquired immunodeficiency syndrome (AIDS) via multiple blood transfusions, who manifested progressive multifocal leukoencephalopathy (PML) about 18 months after the development of AIDS. PML initiated with right hemiparesis, dysphasia, and Gerstmann's syndrome and resulted in death within 2 months after the onset. Neuroimaging examinations revealed white matter lesions mainly in the left posterior parietal lobe. The cortical gray matter also showed abnormal signal intensity. Peripheral CD4+ lymphocyte count was 81/microl. Routine cerebrospinal fluid (CSF) examinations were negative. CSF antibodies against herpes simplex virus, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus as well as serum antibody against toxoplasma gondii were negative. Though autopsy or biopsy of the brain was not performed, JC virus genomes were detected in the CSF sample by a polymerase chain reaction, and their sequencing showed unique alterations of the regulatory regions, characteristic to PML-type JC virus.  (+info)

Progressive multifocal leukoencephalopathy (PML) is a rare and serious demyelinating disease of the central nervous system that affects the white matter of the brain. It's caused by the reactivation of the John Cunningham virus (JCV) in immunocompromised individuals, such as those with HIV/AIDS, organ transplants, or hematologic malignancies.

In PML, the JCV infects and destroys the oligodendrocytes, which are the cells responsible for producing myelin, the fatty substance that insulates and protects nerve fibers. This results in multiple areas of focal demyelination throughout the brain, leading to progressive neurological symptoms such as cognitive decline, motor weakness, vision loss, and speech difficulties.

PML is a medical emergency, and prompt diagnosis and treatment of the underlying immunodeficiency are crucial for improving outcomes. Unfortunately, there is no specific treatment for PML itself, but restoring immune function can help slow or stop the progression of the disease.

The JC (John Cunningham) virus, also known as human polyomavirus 2 (HPyV-2), is a type of double-stranded DNA virus that belongs to the Polyomaviridae family. It is named after the initials of the patient in whom it was first identified.

JC virus is a ubiquitous virus, meaning that it is commonly found in the general population worldwide. Most people get infected with JC virus during childhood and do not experience any symptoms. After the initial infection, the virus remains dormant in the kidneys and other organs of the body.

However, in individuals with weakened immune systems, such as those with HIV/AIDS or who have undergone organ transplantation, JC virus can reactivate and cause a serious brain infection called progressive multifocal leukoencephalopathy (PML). PML is a rare but often fatal disease that affects the white matter of the brain, causing cognitive decline, weakness, and paralysis.

There is currently no cure for PML, and treatment is focused on managing the underlying immune deficiency and controlling the symptoms of the disease.

Leukoencephalopathies are a group of medical conditions that primarily affect the white matter of the brain, which consists mainly of nerve fibers covered by myelin sheaths. These conditions are characterized by abnormalities in the structure and function of the white matter, leading to various neurological symptoms such as cognitive decline, motor impairment, seizures, and behavioral changes.

The term "leukoencephalopathy" is derived from two Greek words: "leukos," meaning white, and "enkephalos," meaning brain. The suffix "-pathy" refers to a disease or suffering. Therefore, leukoencephalopathies refer specifically to diseases that affect the white matter of the brain.

There are various types of leukoencephalopathies, including genetic, metabolic, infectious, toxic, and immune-mediated forms. Some examples include multiple sclerosis, adrenoleukodystrophy, Alexander disease, Canavan disease, and Marchiafava-Bignami disease. The diagnosis of leukoencephalopathies typically involves a combination of clinical evaluation, imaging studies such as MRI, and sometimes genetic or laboratory testing to identify the underlying cause. Treatment depends on the specific type and severity of the condition and may include medications, dietary modifications, physical therapy, or supportive care.

CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) is a genetic disorder that affects the small blood vessels in the brain. It is caused by mutations in the NOTCH3 gene, which leads to the progressive degeneration of these vessels.

The symptoms of CADASIL typically begin in middle age and include migraine with aura, recurrent strokes or transient ischemic attacks (TIAs), cognitive decline, and psychiatric symptoms such as depression and apathy. The condition can also cause physical disabilities such as difficulty walking and urinary incontinence.

CADASIL is an inherited disorder, meaning that it is passed down from parent to child through a mutated gene. If one parent has the disease, each child has a 50% chance of inheriting the mutated gene and developing the condition. Currently, there is no cure for CADASIL, but treatments can help manage symptoms and improve quality of life.

Polyomavirus infections refer to the infectious diseases caused by polyomaviruses, a type of small, non-enveloped DNA viruses that are capable of infecting humans and animals. There are several different types of polyomaviruses that can cause infection, including JC virus (JCV), BK virus (BKV), KI virus (KIV), WU virus (WUV), and Merkel cell polyomavirus (MCPyV).

Infection with these viruses typically occurs during childhood and is usually asymptomatic or associated with mild respiratory illness. However, in immunocompromised individuals, such as those with HIV/AIDS or organ transplant recipients, polyomavirus infections can lead to more serious complications, including nephropathy (BKV), progressive multifocal leukoencephalopathy (JCV), and Merkel cell carcinoma (MCPyV).

Diagnosis of polyomavirus infections typically involves the detection of viral DNA or antigens in clinical samples, such as blood, urine, or tissue biopsies. Treatment is generally supportive and aimed at managing symptoms, although antiviral therapy may be used in some cases. Prevention strategies include good hygiene practices and avoiding close contact with individuals who are known to be infected.

Posterior Leukoencephalopathy Syndrome (PLS) is a neurological disorder characterized by the presence of vasogenic edema (swelling due to leakage of fluid from blood vessels) in the white matter (part of the brain that contains nerve fibers) of the posterior regions (occipital and parietal lobes) of the brain.

The symptoms of PLS can vary but often include headache, altered mental status, seizures, visual disturbances, and hypertension (high blood pressure). The exact cause of PLS is not fully understood, but it has been associated with certain conditions such as eclampsia, preeclampsia, kidney failure, autoimmune disorders, and the use of certain medications.

PLS is typically diagnosed based on clinical symptoms and imaging studies such as MRI or CT scans. Treatment usually involves addressing the underlying cause of PLS, controlling hypertension if present, and managing seizures if they occur. With prompt and appropriate treatment, most patients with PLS have a good prognosis and recover completely. However, in severe cases, PLS can lead to permanent neurological damage or even death.

Multi-infarct dementia (MID) is a specific type of dementia that is caused by multiple small strokes or mini-strokes (known as transient ischemic attacks or TIAs) in the brain. Also known as vascular dementia, multi-infarct dementia results from the interruption of blood flow to parts of the brain, leading to damage and death of brain tissue.

The term 'multi-infarct' refers to multiple areas (or infarcts) of damaged or dead tissue in the brain due to the lack of oxygen and nutrients caused by these small strokes. Over time, as more areas of the brain are affected, cognitive decline becomes apparent, leading to symptoms such as memory loss, difficulty with problem-solving, disorientation, language problems, and changes in mood or behavior.

Multi-infarct dementia is typically a progressive condition, meaning that symptoms worsen over time. However, the rate of progression can vary depending on factors such as the number and severity of strokes, underlying medical conditions, and lifestyle factors. It's important to note that multi-infarct dementia can be prevented or delayed by controlling risk factors for stroke, such as high blood pressure, diabetes, smoking, and high cholesterol.

Cerebrospinal fluid (CSF) is a clear, colorless fluid that surrounds and protects the brain and spinal cord. It acts as a shock absorber for the central nervous system and provides nutrients to the brain while removing waste products. CSF is produced by specialized cells called ependymal cells in the choroid plexus of the ventricles (fluid-filled spaces) inside the brain. From there, it circulates through the ventricular system and around the outside of the brain and spinal cord before being absorbed back into the bloodstream. CSF analysis is an important diagnostic tool for various neurological conditions, including infections, inflammation, and cancer.

T-lymphocytopenia, idiopathic CD4-positive, also known as Idiopathic CD4 Lymphopenia (ICL), is a rare medical condition characterized by a significant decrease in the number of CD4+ T lymphocytes in the peripheral blood without an identifiable cause. CD4+ T cells are crucial for immune function and protection against certain types of infections, particularly those caused by viruses such as HIV.

ICL is typically defined as a CD4+ T-lymphocyte count below 300 cells/μL in the absence of HIV infection or any other known immunodeficiency disorder. The exact cause of ICL remains unknown, although it has been associated with genetic factors and autoimmune disorders.

People with ICL may be at increased risk for certain types of infections, such as opportunistic infections, which can occur when the immune system is weakened. However, the severity and frequency of infections in individuals with ICL are generally less than those seen in people with HIV-associated CD4 lymphopenia.

Regular monitoring of CD4+ T-lymphocyte counts and appropriate management of any infections that occur are important for people with ICL to maintain their overall health and well-being.

Mianserin is a tetracyclic antidepressant (TCA) that is primarily used to treat major depressive disorders. It functions by inhibiting the reuptake of neurotransmitters such as serotonin and noradrenaline, thereby increasing their availability in the brain and helping to alleviate symptoms of depression.

Mianserin also has additional properties, including antihistamine and anti-cholinergic effects, which can help reduce some side effects commonly associated with other antidepressants, such as insomnia and agitation. However, these same properties can also lead to side effects such as drowsiness, dry mouth, and orthostatic hypotension (a drop in blood pressure upon standing).

It's important to note that mianserin is not commonly prescribed due to its narrow therapeutic index and the risk of serious side effects, including agranulocytosis (a severe decrease in white blood cells), which can increase the risk of infection. As with any medication, it should only be taken under the close supervision of a healthcare provider.

Medical Definition:

Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic imaging technique that uses a strong magnetic field and radio waves to create detailed cross-sectional or three-dimensional images of the internal structures of the body. The patient lies within a large, cylindrical magnet, and the scanner detects changes in the direction of the magnetic field caused by protons in the body. These changes are then converted into detailed images that help medical professionals to diagnose and monitor various medical conditions, such as tumors, injuries, or diseases affecting the brain, spinal cord, heart, blood vessels, joints, and other internal organs. MRI does not use radiation like computed tomography (CT) scans.

The brain is the central organ of the nervous system, responsible for receiving and processing sensory information, regulating vital functions, and controlling behavior, movement, and cognition. It is divided into several distinct regions, each with specific functions:

1. Cerebrum: The largest part of the brain, responsible for higher cognitive functions such as thinking, learning, memory, language, and perception. It is divided into two hemispheres, each controlling the opposite side of the body.
2. Cerebellum: Located at the back of the brain, it is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor skills.
3. Brainstem: Connects the cerebrum and cerebellum to the spinal cord, controlling vital functions such as breathing, heart rate, and blood pressure. It also serves as a relay center for sensory information and motor commands between the brain and the rest of the body.
4. Diencephalon: A region that includes the thalamus (a major sensory relay station) and hypothalamus (regulates hormones, temperature, hunger, thirst, and sleep).
5. Limbic system: A group of structures involved in emotional processing, memory formation, and motivation, including the hippocampus, amygdala, and cingulate gyrus.

The brain is composed of billions of interconnected neurons that communicate through electrical and chemical signals. It is protected by the skull and surrounded by three layers of membranes called meninges, as well as cerebrospinal fluid that provides cushioning and nutrients.

A tumor virus infection is a condition in which a person's cells become cancerous or transformed due to the integration and disruption of normal cellular functions by a viral pathogen. These viruses are also known as oncoviruses, and they can cause tumors or cancer by altering the host cell's genetic material, promoting uncontrolled cell growth and division, evading immune surveillance, and inhibiting apoptosis (programmed cell death).

Examples of tumor viruses include:

1. DNA tumor viruses: These are double-stranded DNA viruses that can cause cancer in humans. Examples include human papillomavirus (HPV), hepatitis B virus (HBV), and Merkel cell polyomavirus (MCV).
2. RNA tumor viruses: Also known as retroviruses, these single-stranded RNA viruses can cause cancer in humans. Examples include human T-cell leukemia virus type 1 (HTLV-1) and human immunodeficiency virus (HIV).

Tumor virus infections are responsible for approximately 15-20% of all cancer cases worldwide, making them a significant public health concern. Prevention strategies, such as vaccination against HPV and HBV, have been shown to reduce the incidence of associated cancers.

Brain diseases, also known as neurological disorders, refer to a wide range of conditions that affect the brain and nervous system. These diseases can be caused by various factors such as genetics, infections, injuries, degeneration, or structural abnormalities. They can affect different parts of the brain, leading to a variety of symptoms and complications.

Some examples of brain diseases include:

1. Alzheimer's disease - a progressive degenerative disorder that affects memory and cognitive function.
2. Parkinson's disease - a movement disorder characterized by tremors, stiffness, and difficulty with coordination and balance.
3. Multiple sclerosis - a chronic autoimmune disease that affects the nervous system and can cause a range of symptoms such as vision loss, muscle weakness, and cognitive impairment.
4. Epilepsy - a neurological disorder characterized by recurrent seizures.
5. Brain tumors - abnormal growths in the brain that can be benign or malignant.
6. Stroke - a sudden interruption of blood flow to the brain, which can cause paralysis, speech difficulties, and other neurological symptoms.
7. Meningitis - an infection of the membranes surrounding the brain and spinal cord.
8. Encephalitis - an inflammation of the brain that can be caused by viruses, bacteria, or autoimmune disorders.
9. Huntington's disease - a genetic disorder that affects muscle coordination, cognitive function, and mental health.
10. Migraine - a neurological condition characterized by severe headaches, often accompanied by nausea, vomiting, and sensitivity to light and sound.

Brain diseases can range from mild to severe and may be treatable or incurable. They can affect people of all ages and backgrounds, and early diagnosis and treatment are essential for improving outcomes and quality of life.

AIDS-related opportunistic infections (AROIs) are infections that occur more frequently or are more severe in people with weakened immune systems, such as those with advanced HIV infection or AIDS. These infections take advantage of a weakened immune system and can affect various organs and systems in the body.

Common examples of AROIs include:

1. Pneumocystis pneumonia (PCP), caused by the fungus Pneumocystis jirovecii
2. Mycobacterium avium complex (MAC) infection, caused by a type of bacteria called mycobacteria
3. Candidiasis, a fungal infection that can affect various parts of the body, including the mouth, esophagus, and genitals
4. Toxoplasmosis, caused by the parasite Toxoplasma gondii
5. Cryptococcosis, a fungal infection that affects the lungs and central nervous system
6. Cytomegalovirus (CMV) infection, caused by a type of herpes virus
7. Tuberculosis (TB), caused by the bacterium Mycobacterium tuberculosis
8. Cryptosporidiosis, a parasitic infection that affects the intestines
9. Progressive multifocal leukoencephalopathy (PML), a viral infection that affects the brain

Preventing and treating AROIs is an important part of managing HIV/AIDS, as they can cause significant illness and even death in people with weakened immune systems. Antiretroviral therapy (ART) is used to treat HIV infection and prevent the progression of HIV to AIDS, which can help reduce the risk of opportunistic infections. In addition, medications to prevent specific opportunistic infections may be prescribed for people with advanced HIV or AIDS.

A fatal outcome is a term used in medical context to describe a situation where a disease, injury, or illness results in the death of an individual. It is the most severe and unfortunate possible outcome of any medical condition, and is often used as a measure of the severity and prognosis of various diseases and injuries. In clinical trials and research, fatal outcome may be used as an endpoint to evaluate the effectiveness and safety of different treatments or interventions.

Viral DNA refers to the genetic material present in viruses that consist of DNA as their core component. Deoxyribonucleic acid (DNA) is one of the two types of nucleic acids that are responsible for storing and transmitting genetic information in living organisms. Viruses are infectious agents much smaller than bacteria that can only replicate inside the cells of other organisms, called hosts.

Viral DNA can be double-stranded (dsDNA) or single-stranded (ssDNA), depending on the type of virus. Double-stranded DNA viruses have a genome made up of two complementary strands of DNA, while single-stranded DNA viruses contain only one strand of DNA.

Examples of dsDNA viruses include Adenoviruses, Herpesviruses, and Poxviruses, while ssDNA viruses include Parvoviruses and Circoviruses. Viral DNA plays a crucial role in the replication cycle of the virus, encoding for various proteins necessary for its multiplication and survival within the host cell.

Immune Reconstitution Inflammatory Syndrome (IRIS) is not a disease itself, but rather a reaction that can occur in some individuals who have a weakened immune system and then receive treatment to restore their immune function.

IRIS is defined as a paradoxical clinical worsening or appearance of new symptoms following the initiation of antiretroviral therapy (ART) in HIV-infected patients, or after the administration of other immunomodulatory agents in patients with other types of immune deficiency.

This reaction is thought to be due to an overactive immune response to opportunistic infections or malignancies that were present but not causing symptoms while the patient's immune system was severely compromised. As the immune system begins to recover, it may mount a strong inflammatory response to these underlying infections or cancers, leading to worsening of symptoms or the development of new ones.

IRIS can affect various organs and systems, causing a wide range of clinical manifestations. The most common opportunistic infections associated with IRIS include Mycobacterium avium complex (MAC), Cytomegalovirus (CMV), Pneumocystis jirovecii pneumonia (PJP), and Cryptococcus neoformans.

The management of IRIS involves a careful balance between continuing the immune-restoring therapy and providing appropriate treatment for the underlying infection or malignancy, while also managing the inflammatory response with anti-inflammatory medications if necessary.

Hereditary Central Nervous System (CNS) Demyelinating Diseases are a group of rare, inherited genetic disorders that affect the nervous system. These diseases are characterized by damage to the myelin sheath, which is the protective covering surrounding nerve fibers in the CNS (brain and spinal cord). The damage to the myelin sheath results in disrupted communication between the brain and other parts of the body, leading to various neurological symptoms.

Examples of Hereditary CNS Demyelinating Diseases include:

1. Leukodystrophies - A group of genetic disorders that affect the white matter (myelin) in the brain. Examples include Pelizaeus-Merzbacher disease, Krabbe disease, and Metachromatic leukodystrophy.
2. Hereditary Spastic Paraplegias (HSPs) - A group of inherited disorders that cause progressive stiffness and weakness in the legs due to damage to the nerve fibers in the spinal cord. Some forms of HSP can also involve CNS demyelination.
3. Neurodegenerative disorders with brain iron accumulation (NBIA) - A group of rare genetic disorders characterized by abnormal accumulation of iron in the brain, which can lead to damage to the myelin sheath and other structures in the brain. Examples include Pantothenate kinase-associated neurodegeneration (PKAN) and Neuroferritinopathy.
4. Cerebrotendinous xanthomatosis - A rare inherited disorder of bile acid metabolism that can lead to progressive neurological symptoms, including demyelination in the brain and spinal cord.

These disorders are typically diagnosed through genetic testing, medical history, physical examination, and imaging studies such as MRI. Treatment is focused on managing symptoms and slowing disease progression, and may include medications, physical therapy, and other supportive care measures.

Polyomavirus is a type of double-stranded DNA virus that belongs to the family Polyomaviridae. These viruses are small, non-enveloped viruses with an icosahedral symmetry. They have a relatively simple structure and contain a circular genome.

Polyomaviruses are known to infect a wide range of hosts, including humans, animals, and birds. In humans, polyomaviruses can cause asymptomatic infections or lead to the development of various diseases, depending on the age and immune status of the host.

There are several types of human polyomaviruses, including:

* JC virus (JCV) and BK virus (BKV), which can cause severe disease in immunocompromised individuals, such as those with HIV/AIDS or organ transplant recipients. JCV is associated with progressive multifocal leukoencephalopathy (PML), a rare but often fatal demyelinating disease of the central nervous system, while BKV can cause nephropathy and hemorrhagic cystitis.
* Merkel cell polyomavirus (MCPyV), which is associated with Merkel cell carcinoma, a rare but aggressive form of skin cancer.
* Trichodysplasia spinulosa-associated polyomavirus (TSV), which is associated with trichodysplasia spinulosa, a rare skin disorder that affects immunocompromised individuals.

Polyomaviruses are typically transmitted through respiratory droplets or direct contact with infected bodily fluids. Once inside the host, they can establish latency in various tissues and organs, where they may remain dormant for long periods of time before reactivating under certain conditions, such as immunosuppression.

Prevention measures include good hygiene practices, such as handwashing and avoiding close contact with infected individuals. There are currently no vaccines available to prevent polyomavirus infections, although research is ongoing to develop effective vaccines against some of the more pathogenic human polyomaviruses.

BK virus, also known as BK polyomavirus, is a type of virus that belongs to the Polyomaviridae family. It is named after the initials of a patient in whom the virus was first isolated. The BK virus is a common infection in humans and is typically acquired during childhood. After the initial infection, the virus remains dormant in the body, often found in the urinary tract and kidneys.

In immunocompetent individuals, the virus usually does not cause any significant problems. However, in people with weakened immune systems, such as those who have undergone organ transplantation or have HIV/AIDS, BK virus can lead to severe complications. One of the most common manifestations of BK virus infection in immunocompromised individuals is hemorrhagic cystitis, a condition characterized by inflammation and bleeding in the bladder. In transplant recipients, BK virus can also cause nephropathy, leading to kidney damage or even failure.

There is no specific treatment for BK virus infection, but antiviral medications may be used to help control the virus's replication in some cases. Maintaining a strong immune system and monitoring viral load through regular testing are essential strategies for managing BK virus infections in immunocompromised individuals.

Integrin α4 (also known as CD49d or ITGA4) is a subunit of integrin proteins, which are heterodimeric transmembrane receptors that mediate cell-cell and cell-extracellular matrix interactions. Integrin α4 typically pairs with β1 (CD29 or ITGB1) or β7 (ITGB7) subunits to form integrins α4β1 and α4β7, respectively.

Integrin α4β1, also known as very late antigen-4 (VLA-4), is widely expressed on various hematopoietic cells, including lymphocytes, monocytes, eosinophils, and basophils. It plays crucial roles in the adhesion, migration, and homing of these cells to secondary lymphoid organs, as well as in the recruitment of immune cells to inflammatory sites. Integrin α4β1 binds to its ligands, vascular cell adhesion molecule-1 (VCAM-1) and fibronectin, via the arginine-glycine-aspartic acid (RGD) motif.

Integrin α4β7, on the other hand, is primarily expressed on gut-homing lymphocytes and interacts with mucosal addressin cell adhesion molecule-1 (MAdCAM-1), a protein mainly found in the high endothelial venules of intestinal Peyer's patches and mesenteric lymph nodes. This interaction facilitates the trafficking of immune cells to the gastrointestinal tract, where they participate in immune responses against pathogens and maintain gut homeostasis.

In summary, Integrin α4 is a crucial subunit of integrins that mediates cell adhesion, migration, and homing to specific tissues through its interactions with various ligands. Dysregulation of integrin α4 has been implicated in several pathological conditions, including inflammatory diseases, autoimmune disorders, and cancer metastasis.

Central nervous system (CNS) cysts are abnormal fluid-filled sacs that develop in the brain or spinal cord. These cysts can be congenital, meaning they are present at birth and develop as a result of abnormal embryonic development, or they can be acquired later in life due to injury, infection, or disease.

CNS cysts can vary in size and may cause symptoms depending on their location and the amount of pressure they place on surrounding brain or spinal cord tissue. Symptoms may include headaches, seizures, weakness, numbness, or difficulty with coordination and balance. In some cases, CNS cysts may not cause any symptoms and may be discovered incidentally during imaging studies performed for other reasons.

There are several types of CNS cysts, including:

1. Arachnoid cysts: These are the most common type of CNS cyst and occur between the layers of the arachnoid membrane that covers the brain and spinal cord.
2. Colloid cysts: These cysts typically develop at the junction of the third and fourth ventricles in the brain and can obstruct the flow of cerebrospinal fluid (CSF), leading to increased intracranial pressure.
3. Ependymal cysts: These cysts arise from the ependymal cells that line the ventricular system of the brain and can cause symptoms by compressing surrounding brain tissue.
4. Neuroglial cysts: These cysts are composed of glial cells, which support and protect nerve cells in the CNS.
5. Pineal cysts: These cysts develop in the pineal gland, a small endocrine gland located near the center of the brain.

Treatment for CNS cysts depends on their size, location, and symptoms. In some cases, observation and monitoring may be all that is necessary. However, if the cyst is causing significant symptoms or is at risk of rupturing or obstructing CSF flow, surgical intervention may be required to remove or reduce the size of the cyst.

Akinetic mutism is a neurological condition characterized by a severe decrease in initiating and sustaining voluntary movements and speech, along with a decreased level of responsiveness to the environment. It is often caused by damage to the frontal lobe of the brain, particularly to the anterior cingulate cortex and its connections to other parts of the brain.

People with akinetic mutism may appear awake and have their eyes open, but they are generally unresponsive to external stimuli and do not initiate voluntary movements or speech on their own. They may occasionally respond to direct questions or commands, but their responses are often limited and delayed. The condition can be caused by various factors, including brain injury, stroke, tumors, infections, or degenerative diseases such as Parkinson's disease.

Akinetic mutism is distinct from a vegetative state, which is characterized by the absence of both awareness and sleep-wake cycles. In contrast, people with akinetic mutism may retain some degree of awareness and have sleep-wake cycles, although their level of responsiveness is significantly reduced.

AIDS Dementia Complex (ADC) is a neurological disorder that occurs in people with advanced HIV infection or AIDS. It is also known as HIV-associated dementia (HAD) or HIV encephalopathy. ADC is characterized by cognitive impairment, motor dysfunction, and behavioral changes that can significantly affect the individual's daily functioning and quality of life.

The symptoms of AIDS Dementia Complex may include:
- Difficulty with concentration and memory
- Slowness in thinking, processing information, or making decisions
- Changes in mood or personality, such as depression, irritability, or apathy
- Difficulty with coordination, balance, or speech
- Progressive weakness and wasting of muscles
- Difficulty with swallowing or speaking

The exact cause of ADC is not fully understood, but it is believed to be related to the direct effects of HIV on the brain. The virus can infect and damage nerve cells, leading to inflammation and degeneration of brain tissue. Treatment for ADC typically involves antiretroviral therapy (ART) to control HIV replication, as well as medications to manage specific symptoms. In some cases, supportive care such as physical therapy or occupational therapy may also be recommended.

HLA-B18 is a specific type of human leukocyte antigen (HLA) Class I antigen, which is encoded by the HLA-B gene located on chromosome 6 in humans. The HLA system is responsible for regulating the immune system and determining compatibility for organ transplantation.

The HLA-B18 antigen is a protein found on the surface of cells that plays a crucial role in the body's immune response by presenting pieces of proteins from viruses, bacteria, and other foreign substances to T-cells, which are white blood cells that help protect the body against infection and disease.

The HLA-B18 antigen is one of many different HLA types that can be found in the human population, and it has been associated with certain diseases or conditions, such as an increased risk of developing certain types of cancer or a decreased likelihood of rejecting a kidney transplant. However, the presence or absence of this antigen alone does not necessarily indicate the presence or absence of disease.

Opportunistic infections (OIs) are infections that occur more frequently or are more severe in individuals with weakened immune systems, often due to a underlying condition such as HIV/AIDS, cancer, or organ transplantation. These infections are caused by microorganisms that do not normally cause disease in people with healthy immune function, but can take advantage of an opportunity to infect and cause damage when the body's defense mechanisms are compromised. Examples of opportunistic infections include Pneumocystis pneumonia, tuberculosis, candidiasis (thrush), and cytomegalovirus infection. Preventive measures, such as antimicrobial medications and vaccinations, play a crucial role in reducing the risk of opportunistic infections in individuals with weakened immune systems.

Demyelinating diseases are a group of disorders that are characterized by damage to the myelin sheath, which is the protective covering surrounding nerve fibers in the brain, optic nerves, and spinal cord. Myelin is essential for the rapid transmission of nerve impulses, and its damage results in disrupted communication between the brain and other parts of the body.

The most common demyelinating disease is multiple sclerosis (MS), where the immune system mistakenly attacks the myelin sheath. Other demyelinating diseases include:

1. Acute Disseminated Encephalomyelitis (ADEM): An autoimmune disorder that typically follows a viral infection or vaccination, causing widespread inflammation and demyelination in the brain and spinal cord.
2. Neuromyelitis Optica (NMO) or Devic's Disease: A rare autoimmune disorder that primarily affects the optic nerves and spinal cord, leading to severe vision loss and motor disability.
3. Transverse Myelitis: Inflammation of the spinal cord causing damage to both sides of one level (segment) of the spinal cord, resulting in various neurological symptoms such as muscle weakness, numbness, or pain, depending on which part of the spinal cord is affected.
4. Guillain-Barré Syndrome: An autoimmune disorder that causes rapid-onset muscle weakness, often beginning in the legs and spreading to the upper body, including the face and breathing muscles. It occurs when the immune system attacks the peripheral nerves' myelin sheath.
5. Central Pontine Myelinolysis (CPM): A rare neurological disorder caused by rapid shifts in sodium levels in the blood, leading to damage to the myelin sheath in a specific area of the brainstem called the pons.

These diseases can result in various symptoms, such as muscle weakness, numbness, vision loss, difficulty with balance and coordination, and cognitive impairment, depending on the location and extent of the demyelination. Treatment typically focuses on managing symptoms, modifying the immune system's response, and promoting nerve regeneration and remyelination when possible.

Gerstmann syndrome is a rare neurological disorder primarily characterized by the following four symptoms:
1. Finger agnosia - inability to identify or recognize fingers on their own hand, often struggling to distinguish between similar fingers like index and middle finger.
2. Left-right disorientation - difficulty determining left from right, sometimes affecting body awareness and spatial orientation.
3. Agraphia - an impairment in writing abilities, including difficulties with spelling, grammar, or composing coherent texts.
4. Acalculia - inability to perform basic arithmetic calculations or have trouble understanding numerical concepts.

These symptoms are typically associated with damage to the dominant parietal lobe, specifically within the angular gyrus region of the brain. Gerstmann syndrome is often observed in individuals who have experienced stroke, brain injury, or other forms of neurological damage. It's important to note that not all individuals with Gerstmann syndrome will exhibit all four symptoms, and some may experience additional cognitive or motor impairments depending on the extent of the brain damage.

Relapsing-remitting multiple sclerosis (RRMS) is a type of multiple sclerosis (MS), which is a chronic autoimmune disease that affects the central nervous system (CNS). In RRMS, the immune system attacks the protective covering of nerve fibers (myelin sheath) in the CNS, leading to the formation of lesions or scars (scleroses). These attacks result in episodes of new or worsening symptoms, known as relapses or exacerbations.

The distinguishing feature of RRMS is that these relapses are followed by periods of partial or complete recovery (remissions), during which symptoms may improve, stabilize, or even disappear temporarily. The duration and severity of relapses and remissions can vary significantly among individuals with RRMS. Over time, the accumulation of damage to the nervous system can lead to progressive disability.

Approximately 85% of people with MS are initially diagnosed with the relapsing-remitting form. With appropriate treatment and management, many people with RRMS can effectively manage their symptoms and maintain a good quality of life for several years.

Monoclonal antibodies are laboratory-produced proteins that mimic the immune system's ability to fight off harmful antigens such as viruses and cancer cells. They are created by fusing a single B cell (the type of white blood cell responsible for producing antibodies) with a tumor cell, resulting in a hybrid cell called a hybridoma. This hybridoma can then be cloned to produce a large number of identical cells, all producing the same antibody, hence "monoclonal."

Humanized monoclonal antibodies are a type of monoclonal antibody that have been genetically engineered to include human components. This is done to reduce the risk of an adverse immune response in patients receiving the treatment. In this process, the variable region of the mouse monoclonal antibody, which contains the antigen-binding site, is grafted onto a human constant region. The resulting humanized monoclonal antibody retains the ability to bind to the target antigen while minimizing the immunogenicity associated with murine (mouse) antibodies.

In summary, "antibodies, monoclonal, humanized" refers to a type of laboratory-produced protein that mimics the immune system's ability to fight off harmful antigens, but with reduced immunogenicity due to the inclusion of human components in their structure.

Capsid proteins are the structural proteins that make up the capsid, which is the protective shell of a virus. The capsid encloses the viral genome and helps to protect it from degradation and detection by the host's immune system. Capsid proteins are typically arranged in a symmetrical pattern and can self-assemble into the capsid structure when exposed to the viral genome.

The specific arrangement and composition of capsid proteins vary between different types of viruses, and they play important roles in the virus's life cycle, including recognition and binding to host cells, entry into the cell, and release of the viral genome into the host cytoplasm. Capsid proteins can also serve as targets for antiviral therapies and vaccines.

An immunocompromised host refers to an individual who has a weakened or impaired immune system, making them more susceptible to infections and decreased ability to fight off pathogens. This condition can be congenital (present at birth) or acquired (developed during one's lifetime).

Acquired immunocompromised states may result from various factors such as medical treatments (e.g., chemotherapy, radiation therapy, immunosuppressive drugs), infections (e.g., HIV/AIDS), chronic diseases (e.g., diabetes, malnutrition, liver disease), or aging.

Immunocompromised hosts are at a higher risk for developing severe and life-threatening infections due to their reduced immune response. Therefore, they require special consideration when it comes to prevention, diagnosis, and treatment of infectious diseases.

Acquired Immunodeficiency Syndrome (AIDS) is a chronic, life-threatening condition caused by the Human Immunodeficiency Virus (HIV). AIDS is the most advanced stage of HIV infection, characterized by the significant weakening of the immune system, making the person more susceptible to various opportunistic infections and cancers.

The medical definition of AIDS includes specific criteria based on CD4+ T-cell count or the presence of certain opportunistic infections and diseases. According to the Centers for Disease Control and Prevention (CDC), a person with HIV is diagnosed with AIDS when:

1. The CD4+ T-cell count falls below 200 cells per cubic millimeter of blood (mm3) - a normal range is typically between 500 and 1,600 cells/mm3.
2. They develop one or more opportunistic infections or cancers that are indicative of advanced HIV disease, regardless of their CD4+ T-cell count.

Some examples of these opportunistic infections and cancers include:

* Pneumocystis pneumonia (PCP)
* Candidiasis (thrush) affecting the esophagus, trachea, or lungs
* Cryptococcal meningitis
* Toxoplasmosis of the brain
* Cytomegalovirus disease
* Kaposi's sarcoma
* Non-Hodgkin's lymphoma
* Invasive cervical cancer

It is important to note that with appropriate antiretroviral therapy (ART), people living with HIV can maintain their CD4+ T-cell counts, suppress viral replication, and prevent the progression to AIDS. Early diagnosis and consistent treatment are crucial for managing HIV and improving life expectancy and quality of life.

Multiple Sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system (CNS), which includes the brain, spinal cord, and optic nerves. In MS, the immune system mistakenly attacks the protective covering of nerve fibers, called myelin, leading to damage and scarring (sclerosis). This results in disrupted communication between the brain and the rest of the body, causing a variety of neurological symptoms that can vary widely from person to person.

The term "multiple" refers to the numerous areas of scarring that occur throughout the CNS in this condition. The progression, severity, and specific symptoms of MS are unpredictable and may include vision problems, muscle weakness, numbness or tingling, difficulty with balance and coordination, cognitive impairment, and mood changes. There is currently no cure for MS, but various treatments can help manage symptoms, modify the course of the disease, and improve quality of life for those affected.

Hypertensive encephalopathy is a serious neurological condition that occurs due to extremely high blood pressure, which is not adequately controlled. This leads to the leakage of fluid and blood into the brain (cerebral edema) and disrupts the normal functioning of the brain. Symptoms may include severe headache, nausea, vomiting, confusion, seizures, visual disturbances, and in severe cases, coma. Immediate medical attention is required to reduce blood pressure and prevent potential long-term damage or even death.

Neuroglia, also known as glial cells or simply glia, are non-neuronal cells that provide support and protection for neurons in the nervous system. They maintain homeostasis, form myelin sheaths around nerve fibers, and provide structural support. They also play a role in the immune response of the central nervous system. Some types of neuroglia include astrocytes, oligodendrocytes, microglia, and ependymal cells.

Oligodendroglia are a type of neuroglial cell found in the central nervous system (CNS) of vertebrates, including humans. These cells play a crucial role in providing support and insulation to nerve fibers (axons) in the CNS, which includes the brain and spinal cord.

More specifically, oligodendroglia produce a fatty substance called myelin that wraps around axons, forming myelin sheaths. This myelination process helps to increase the speed of electrical impulse transmission (nerve impulses) along the axons, allowing for efficient communication between different neurons.

In addition to their role in myelination, oligodendroglia also contribute to the overall health and maintenance of the CNS by providing essential nutrients and supporting factors to neurons. Dysfunction or damage to oligodendroglia has been implicated in various neurological disorders, such as multiple sclerosis (MS), where demyelination of axons leads to impaired nerve function and neurodegeneration.

Organophosphonates are a class of organic compounds characterized by the presence of a carbon-phosphorus bond. They contain a phosphonic acid group, which consists of a phosphorus atom bonded to four oxygen or nitrogen atoms, with one of those bonds being replaced by a carbon atom.

In a medical context, organophosphonates are commonly used as radiopharmaceuticals in diagnostic nuclear medicine procedures, such as bone scans. These compounds have the ability to bind to hydroxyapatite, the mineral component of bones, and can be labeled with radioactive isotopes for imaging purposes. They may also be used in therapeutic settings, including as treatments for conditions such as tumor-induced hypercalcemia and Paget's disease of bone.

It is important to note that organophosphonates are distinct from organophosphates, another class of compounds that contain a phosphorus atom bonded to three oxygen or sulfur atoms and one carbon atom. Organophosphates have been widely used as pesticides and chemical warfare agents, and can pose significant health risks due to their toxicity.

Antigens are substances that trigger an immune response in the body, leading to the production of antibodies. Antigens can be proteins, polysaccharides, or other molecules found on the surface of cells or viruses.

Viral antigens are antigens that are present on the surface of viruses. When a virus infects a cell, it may display viral antigens on the surface of the infected cell. This can alert the immune system to the presence of the virus and trigger an immune response.

Tumor antigens are antigens that are present on the surface of cancer cells. These antigens may be unique to the cancer cells, or they may be similar to antigens found on normal cells. Tumor antigens can be recognized by the immune system as foreign, leading to an immune response against the cancer cells.

It is important to note that not all viral infections lead to cancer, and not all tumors are caused by viruses. However, some viruses have been linked to an increased risk of certain types of cancer. For example, human papillomavirus (HPV) has been associated with an increased risk of cervical, anal, and oral cancers. In these cases, the virus may introduce viral antigens into the cells it infects, leading to an altered presentation of tumor antigens on the surface of the infected cells. This can potentially trigger an immune response against both the viral antigens and the tumor antigens, which may help to prevent or slow the growth of the cancer.

Vascular dementia is a type of dementia that is caused by damage to the blood vessels that supply blood to the brain. This damage can result from conditions such as stroke, chronic high blood pressure, diabetes, or other diseases that affect the circulatory system. The interruption in blood flow to the brain can lead to damaged or dead brain cells, which can impair cognitive function and cause symptoms similar to those seen in other types of dementia, such as Alzheimer's disease.

The symptoms of vascular dementia can vary depending on the severity and location of the damage to the blood vessels. However, common symptoms include difficulties with memory, attention, and decision-making; problems with language and speech; changes in mood or behavior; and difficulty walking or performing other physical tasks. Vascular dementia is typically a progressive condition, meaning that the symptoms tend to worsen over time.

It's important to note that vascular dementia can coexist with other types of dementia, such as Alzheimer's disease, and this is known as mixed dementia. Proper diagnosis and management of underlying medical conditions that contribute to vascular dementia can help slow down the progression of cognitive decline and improve quality of life for individuals living with this condition.

Mefloquine is an antimalarial medication that is used to prevent and treat malaria caused by the Plasmodium falciparum parasite. It works by interfering with the growth of the parasite in the red blood cells of the body. Mefloquine is a synthetic quinoline compound, and it is available under the brand name Lariam, among others.

Mefloquine is typically taken once a week, starting one to two weeks before traveling to an area where malaria is common, and continuing for four weeks after leaving the area. It may also be used to treat acute malaria infection in conjunction with other antimalarial medications.

It's important to note that mefloquine has been associated with serious neuropsychiatric side effects, including anxiety, depression, hallucinations, and seizures. Therefore, it is usually reserved for use in situations where other antimalarial drugs cannot be used or have failed. Before taking mefloquine, individuals should discuss their medical history and potential risks with their healthcare provider.

Central nervous system (CNS) diseases refer to medical conditions that primarily affect the brain and spinal cord. The CNS is responsible for controlling various functions in the body, including movement, sensation, cognition, and behavior. Therefore, diseases of the CNS can have significant impacts on a person's quality of life and overall health.

There are many different types of CNS diseases, including:

1. Infectious diseases: These are caused by viruses, bacteria, fungi, or parasites that infect the brain or spinal cord. Examples include meningitis, encephalitis, and polio.
2. Neurodegenerative diseases: These are characterized by progressive loss of nerve cells in the brain or spinal cord. Examples include Alzheimer's disease, Parkinson's disease, and Huntington's disease.
3. Structural diseases: These involve damage to the physical structure of the brain or spinal cord, such as from trauma, tumors, or stroke.
4. Functional diseases: These affect the function of the nervous system without obvious structural damage, such as multiple sclerosis and epilepsy.
5. Genetic disorders: Some CNS diseases are caused by genetic mutations, such as spinal muscular atrophy and Friedreich's ataxia.

Symptoms of CNS diseases can vary widely depending on the specific condition and the area of the brain or spinal cord that is affected. They may include muscle weakness, paralysis, seizures, loss of sensation, difficulty with coordination and balance, confusion, memory loss, changes in behavior or mood, and pain. Treatment for CNS diseases depends on the specific condition and may involve medications, surgery, rehabilitation therapy, or a combination of these approaches.

Polymerase Chain Reaction (PCR) is a laboratory technique used to amplify specific regions of DNA. It enables the production of thousands to millions of copies of a particular DNA sequence in a rapid and efficient manner, making it an essential tool in various fields such as molecular biology, medical diagnostics, forensic science, and research.

The PCR process involves repeated cycles of heating and cooling to separate the DNA strands, allow primers (short sequences of single-stranded DNA) to attach to the target regions, and extend these primers using an enzyme called Taq polymerase, resulting in the exponential amplification of the desired DNA segment.

In a medical context, PCR is often used for detecting and quantifying specific pathogens (viruses, bacteria, fungi, or parasites) in clinical samples, identifying genetic mutations or polymorphisms associated with diseases, monitoring disease progression, and evaluating treatment effectiveness.

Cytosine is one of the four nucleobases in the nucleic acid molecules DNA and RNA, along with adenine, guanine, and thymine (in DNA) or uracil (in RNA). The single-letter abbreviation for cytosine is "C."

Cytosine base pairs specifically with guanine through hydrogen bonding, forming a base pair. In DNA, the double helix consists of two complementary strands of nucleotides held together by these base pairs, such that the sequence of one strand determines the sequence of the other. This property is critical for DNA replication and transcription, processes that are essential for life.

Cytosine residues in DNA can undergo spontaneous deamination to form uracil, which can lead to mutations if not corrected by repair mechanisms. In RNA, cytosine can be methylated at the 5-carbon position to form 5-methylcytosine, a modification that plays a role in regulating gene expression and other cellular processes.

Polyomavirus transforming antigens refer to specific proteins expressed by polyomaviruses that can induce cellular transformation and lead to the development of cancer. These antigens are called large T antigen (T-Ag) and small t antigen (t-Ag). They manipulate key cellular processes, such as cell cycle regulation and DNA damage response, leading to uncontrolled cell growth and malignant transformation.

The large T antigen is a multifunctional protein that plays a crucial role in viral replication and transformation. It has several domains with different functions:

1. Origin binding domain (OBD): Binds to the viral origin of replication, initiating DNA synthesis.
2. Helicase domain: Unwinds double-stranded DNA during replication.
3. DNA binding domain: Binds to specific DNA sequences and acts as a transcriptional regulator.
4. Protein phosphatase 1 (PP1) binding domain: Recruits PP1 to promote viral DNA replication and inhibit host cell defense mechanisms.
5. p53-binding domain: Binds and inactivates the tumor suppressor protein p53, promoting cell cycle progression and preventing apoptosis.
6. Rb-binding domain: Binds to and inactivates the retinoblastoma protein (pRb), leading to deregulation of the cell cycle and uncontrolled cell growth.

The small t antigen shares a common N-terminal region with large T antigen but lacks some functional domains, such as the OBD and helicase domain. Small t antigen can also bind to and inactivate PP1 and pRb, contributing to transformation. However, its primary role is to stabilize large T antigen by preventing its proteasomal degradation.

Polyomavirus transforming antigens are associated with various human cancers, such as Merkel cell carcinoma (caused by Merkel cell polyomavirus) and some forms of brain tumors, sarcomas, and lymphomas (associated with simian virus 40).

Urine is a physiological excretory product that is primarily composed of water, urea, and various ions (such as sodium, potassium, chloride, and others) that are the byproducts of protein metabolism. It also contains small amounts of other substances like uric acid, creatinine, ammonia, and various organic compounds. Urine is produced by the kidneys through a process called urination or micturition, where it is filtered from the blood and then stored in the bladder until it is excreted from the body through the urethra. The color, volume, and composition of urine can provide important diagnostic information about various medical conditions.

Cytarabine is a chemotherapeutic agent used in the treatment of various types of cancer, including leukemias and lymphomas. Its chemical name is cytosine arabinoside, and it works by interfering with the DNA synthesis of cancer cells, which ultimately leads to their death.

Cytarabine is often used in combination with other chemotherapy drugs and may be administered through various routes, such as intravenous (IV) or subcutaneous injection, or orally. The specific dosage and duration of treatment will depend on the type and stage of cancer being treated, as well as the patient's overall health status.

Like all chemotherapy drugs, cytarabine can cause a range of side effects, including nausea, vomiting, diarrhea, hair loss, and an increased risk of infection. It may also cause more serious side effects, such as damage to the liver, kidneys, or nervous system, and it is important for patients to be closely monitored during treatment to minimize these risks.

It's important to note that medical treatments should only be administered under the supervision of a qualified healthcare professional, and this information should not be used as a substitute for medical advice.

Viral encephalitis is a medical condition characterized by inflammation of the brain caused by a viral infection. The infection can be caused by various types of viruses, such as herpes simplex virus, enteroviruses, arboviruses (transmitted through insect bites), or HIV.

The symptoms of viral encephalitis may include fever, headache, stiff neck, confusion, seizures, and altered level of consciousness. In severe cases, it can lead to brain damage, coma, or even death. The diagnosis is usually made based on clinical presentation, laboratory tests, and imaging studies such as MRI or CT scan. Treatment typically involves antiviral medications, supportive care, and management of complications.

HIV (Human Immunodeficiency Virus) infection is a viral illness that progressively attacks and weakens the immune system, making individuals more susceptible to other infections and diseases. The virus primarily infects CD4+ T cells, a type of white blood cell essential for fighting off infections. Over time, as the number of these immune cells declines, the body becomes increasingly vulnerable to opportunistic infections and cancers.

HIV infection has three stages:

1. Acute HIV infection: This is the initial stage that occurs within 2-4 weeks after exposure to the virus. During this period, individuals may experience flu-like symptoms such as fever, fatigue, rash, swollen glands, and muscle aches. The virus replicates rapidly, and the viral load in the body is very high.
2. Chronic HIV infection (Clinical latency): This stage follows the acute infection and can last several years if left untreated. Although individuals may not show any symptoms during this phase, the virus continues to replicate at low levels, and the immune system gradually weakens. The viral load remains relatively stable, but the number of CD4+ T cells declines over time.
3. AIDS (Acquired Immunodeficiency Syndrome): This is the most advanced stage of HIV infection, characterized by a severely damaged immune system and numerous opportunistic infections or cancers. At this stage, the CD4+ T cell count drops below 200 cells/mm3 of blood.

It's important to note that with proper antiretroviral therapy (ART), individuals with HIV infection can effectively manage the virus, maintain a healthy immune system, and significantly reduce the risk of transmission to others. Early diagnosis and treatment are crucial for improving long-term health outcomes and reducing the spread of HIV.

Viral activation, also known as viral reactivation or virus reactivation, refers to the process in which a latent or dormant virus becomes active and starts to replicate within a host cell. This can occur when the immune system is weakened or compromised, allowing the virus to evade the body's natural defenses and cause disease.

In some cases, viral activation can be triggered by certain environmental factors, such as stress, exposure to UV light, or infection with another virus. Once activated, the virus can cause symptoms similar to those seen during the initial infection, or it may lead to new symptoms depending on the specific virus and the host's immune response.

Examples of viruses that can remain dormant in the body and be reactivated include herpes simplex virus (HSV), varicella-zoster virus (VZV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV). It is important to note that not all viruses can be reactivated, and some may remain dormant in the body indefinitely without causing any harm.

"Gene rearrangement" is a process that involves the alteration of the order, orientation, or copy number of genes or gene segments within an organism's genome. This natural mechanism plays a crucial role in generating diversity and specificity in the immune system, particularly in vertebrates.

In the context of the immune system, gene rearrangement occurs during the development of B-cells and T-cells, which are responsible for adaptive immunity. The process involves breaking and rejoining DNA segments that encode antigen recognition sites, resulting in a unique combination of gene segments and creating a vast array of possible antigen receptors.

There are two main types of gene rearrangement:

1. V(D)J recombination: This process occurs in both B-cells and T-cells. It involves the recombination of variable (V), diversity (D), and joining (J) gene segments to form a functional antigen receptor gene. In humans, there are multiple copies of V, D, and J segments for each antigen receptor gene, allowing for a vast number of possible combinations.
2. Class switch recombination: This process occurs only in mature B-cells after antigen exposure. It involves the replacement of the constant (C) region of the immunoglobulin heavy chain gene with another C region, resulting in the production of different isotypes of antibodies (IgG, IgA, or IgE) that have distinct effector functions while maintaining the same antigen specificity.

These processes contribute to the generation of a diverse repertoire of antigen receptors, allowing the immune system to recognize and respond effectively to a wide range of pathogens.

Notch receptors are a type of transmembrane receptor proteins that play crucial roles in cell-cell communication and regulation of various biological processes, including cell fate determination, differentiation, proliferation, and apoptosis. These receptors are highly conserved across species and are essential for normal development and tissue homeostasis.

The Notch signaling pathway is initiated when the extracellular domain of a Notch receptor on one cell interacts with its ligand (such as Delta or Jagged) on an adjacent cell. This interaction triggers a series of proteolytic cleavage events that release the intracellular domain of the Notch receptor, which then translocates to the nucleus and regulates gene expression by interacting with transcription factors like CSL (CBF1/RBP-Jκ/Su(H)/Lag-1).

There are four known Notch receptors in humans (Notch1-4) that share a similar structure, consisting of an extracellular domain containing multiple epidermal growth factor (EGF)-like repeats, a transmembrane domain, and an intracellular domain. Mutations or dysregulation of the Notch signaling pathway have been implicated in various human diseases, including cancer, cardiovascular disorders, and developmental abnormalities.

Antiretroviral Therapy, Highly Active (HAART) is a medical treatment regimen used to manage HIV infection. It involves the combination of three or more antiretroviral drugs from at least two different classes, aiming to maximally suppress viral replication and prevent the development of drug resistance. The goal of HAART is to reduce the amount of HIV in the body to undetectable levels, preserve immune function, and improve quality of life for people living with HIV. Commonly used antiretroviral classes include nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), integrase strand transfer inhibitors (INSTIs), and fusion inhibitors.

Monoclonal murine-derived antibodies are a type of laboratory-produced antibody that is identical in structure, having been derived from a single clone of cells. These antibodies are created using mouse cells and are therefore composed entirely of mouse immune proteins. They are designed to bind specifically to a particular target protein or antigen, making them useful tools for research, diagnostic testing, and therapeutic applications.

Monoclonal antibodies offer several advantages over polyclonal antibodies (which are derived from multiple clones of cells and can recognize multiple epitopes on an antigen). Monoclonal antibodies have a consistent and uniform structure, making them more reliable for research and diagnostic purposes. They also have higher specificity and affinity for their target antigens, allowing for more sensitive detection and measurement.

However, there are some limitations to using monoclonal murine-derived antibodies in therapeutic applications. Because they are composed entirely of mouse proteins, they can elicit an immune response in humans, leading to the production of human anti-mouse antibodies (HAMA) that can neutralize their effectiveness. To overcome this limitation, researchers have developed chimeric and humanized monoclonal antibodies that incorporate human protein sequences, reducing the risk of an immune response.

Central nervous system (CNS) infections refer to infectious processes that affect the brain, spinal cord, and their surrounding membranes, known as meninges. These infections can be caused by various microorganisms, including bacteria, viruses, fungi, and parasites. Examples of CNS infections are:

1. Meningitis: Inflammation of the meninges, usually caused by bacterial or viral infections. Bacterial meningitis is a medical emergency that requires immediate treatment.
2. Encephalitis: Inflammation of the brain parenchyma, often caused by viral infections. Some viruses associated with encephalitis include herpes simplex virus, enteroviruses, and arboviruses.
3. Meningoencephalitis: A combined inflammation of both the brain and meninges, commonly seen in certain viral infections or when bacterial pathogens directly invade the brain.
4. Brain abscess: A localized collection of pus within the brain caused by a bacterial or fungal infection.
5. Spinal epidural abscess: An infection in the space surrounding the spinal cord, usually caused by bacteria.
6. Myelitis: Inflammation of the spinal cord, which can result from viral, bacterial, or fungal infections.
7. Rarely, parasitic infections like toxoplasmosis and cysticercosis can also affect the CNS.

Symptoms of CNS infections may include fever, headache, stiff neck, altered mental status, seizures, focal neurological deficits, or meningeal signs (e.g., Brudzinski's and Kernig's signs). The specific symptoms depend on the location and extent of the infection, as well as the causative organism. Prompt diagnosis and treatment are crucial to prevent long-term neurological complications or death.

Monoclonal antibodies are a type of antibody that are identical because they are produced by a single clone of cells. They are laboratory-produced molecules that act like human antibodies in the immune system. They can be designed to attach to specific proteins found on the surface of cancer cells, making them useful for targeting and treating cancer. Monoclonal antibodies can also be used as a therapy for other diseases, such as autoimmune disorders and inflammatory conditions.

Monoclonal antibodies are produced by fusing a single type of immune cell, called a B cell, with a tumor cell to create a hybrid cell, or hybridoma. This hybrid cell is then able to replicate indefinitely, producing a large number of identical copies of the original antibody. These antibodies can be further modified and engineered to enhance their ability to bind to specific targets, increase their stability, and improve their effectiveness as therapeutic agents.

Monoclonal antibodies have several mechanisms of action in cancer therapy. They can directly kill cancer cells by binding to them and triggering an immune response. They can also block the signals that promote cancer growth and survival. Additionally, monoclonal antibodies can be used to deliver drugs or radiation directly to cancer cells, increasing the effectiveness of these treatments while minimizing their side effects on healthy tissues.

Monoclonal antibodies have become an important tool in modern medicine, with several approved for use in cancer therapy and other diseases. They are continuing to be studied and developed as a promising approach to treating a wide range of medical conditions.

Immunosuppressive agents are medications that decrease the activity of the immune system. They are often used to prevent the rejection of transplanted organs and to treat autoimmune diseases, where the immune system mistakenly attacks the body's own tissues. These drugs work by interfering with the immune system's normal responses, which helps to reduce inflammation and damage to tissues. However, because they suppress the immune system, people who take immunosuppressive agents are at increased risk for infections and other complications. Examples of immunosuppressive agents include corticosteroids, azathioprine, cyclophosphamide, mycophenolate mofetil, tacrolimus, and sirolimus.

Viral regulatory and accessory proteins are a type of viral protein that play a role in the regulation of viral replication, gene expression, and host immune response. These proteins are not directly involved in the structural components of the virus but instead help to modulate the environment inside the host cell to facilitate viral replication and evade the host's immune system.

Regulatory proteins control various stages of the viral life cycle, such as transcription, translation, and genome replication. They may also interact with host cell regulatory proteins to alter their function and promote viral replication. Accessory proteins, on the other hand, are non-essential for viral replication but can enhance viral pathogenesis or modulate the host's immune response.

The specific functions of viral regulatory and accessory proteins vary widely among different viruses. For example, in human immunodeficiency virus (HIV), the Tat protein is a regulatory protein that activates transcription of the viral genome, while the Vpu protein is an accessory protein that downregulates the expression of CD4 receptors on host cells to prevent superinfection.

Understanding the functions of viral regulatory and accessory proteins is important for developing antiviral therapies and vaccines, as these proteins can be potential targets for inhibiting viral replication or modulating the host's immune response.

Disease progression is the worsening or advancement of a medical condition over time. It refers to the natural course of a disease, including its development, the severity of symptoms and complications, and the impact on the patient's overall health and quality of life. Understanding disease progression is important for developing appropriate treatment plans, monitoring response to therapy, and predicting outcomes.

The rate of disease progression can vary widely depending on the type of medical condition, individual patient factors, and the effectiveness of treatment. Some diseases may progress rapidly over a short period of time, while others may progress more slowly over many years. In some cases, disease progression may be slowed or even halted with appropriate medical interventions, while in other cases, the progression may be inevitable and irreversible.

In clinical practice, healthcare providers closely monitor disease progression through regular assessments, imaging studies, and laboratory tests. This information is used to guide treatment decisions and adjust care plans as needed to optimize patient outcomes and improve quality of life.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

Simian Virus 40 (SV40) is a polyomavirus that is found in both monkeys and humans. It is a DNA virus that has been extensively studied in laboratory settings due to its ability to transform cells and cause tumors in animals. In fact, SV40 was discovered as a contaminant of poliovirus vaccines that were prepared using rhesus monkey kidney cells in the 1950s and 1960s.

SV40 is not typically associated with human disease, but there has been some concern that exposure to the virus through contaminated vaccines or other means could increase the risk of certain types of cancer, such as mesothelioma and brain tumors. However, most studies have failed to find a consistent link between SV40 infection and cancer in humans.

The medical community generally agrees that SV40 is not a significant public health threat, but researchers continue to study the virus to better understand its biology and potential impact on human health.

A biopsy is a medical procedure in which a small sample of tissue is taken from the body to be examined under a microscope for the presence of disease. This can help doctors diagnose and monitor various medical conditions, such as cancer, infections, or autoimmune disorders. The type of biopsy performed will depend on the location and nature of the suspected condition. Some common types of biopsies include:

1. Incisional biopsy: In this procedure, a surgeon removes a piece of tissue from an abnormal area using a scalpel or other surgical instrument. This type of biopsy is often used when the lesion is too large to be removed entirely during the initial biopsy.

2. Excisional biopsy: An excisional biopsy involves removing the entire abnormal area, along with a margin of healthy tissue surrounding it. This technique is typically employed for smaller lesions or when cancer is suspected.

3. Needle biopsy: A needle biopsy uses a thin, hollow needle to extract cells or fluid from the body. There are two main types of needle biopsies: fine-needle aspiration (FNA) and core needle biopsy. FNA extracts loose cells, while a core needle biopsy removes a small piece of tissue.

4. Punch biopsy: In a punch biopsy, a round, sharp tool is used to remove a small cylindrical sample of skin tissue. This type of biopsy is often used for evaluating rashes or other skin abnormalities.

5. Shave biopsy: During a shave biopsy, a thin slice of tissue is removed from the surface of the skin using a sharp razor-like instrument. This technique is typically used for superficial lesions or growths on the skin.

After the biopsy sample has been collected, it is sent to a laboratory where a pathologist will examine the tissue under a microscope and provide a diagnosis based on their findings. The results of the biopsy can help guide further treatment decisions and determine the best course of action for managing the patient's condition.

Gene expression regulation, viral, refers to the processes that control the production of viral gene products, such as proteins and nucleic acids, during the viral life cycle. This can involve both viral and host cell factors that regulate transcription, RNA processing, translation, and post-translational modifications of viral genes.

Viral gene expression regulation is critical for the virus to replicate and produce progeny virions. Different types of viruses have evolved diverse mechanisms to regulate their gene expression, including the use of promoters, enhancers, transcription factors, RNA silencing, and epigenetic modifications. Understanding these regulatory processes can provide insights into viral pathogenesis and help in the development of antiviral therapies.

Antiviral agents are a class of medications that are designed to treat infections caused by viruses. Unlike antibiotics, which target bacteria, antiviral agents interfere with the replication and infection mechanisms of viruses, either by inhibiting their ability to replicate or by modulating the host's immune response to the virus.

Antiviral agents are used to treat a variety of viral infections, including influenza, herpes simplex virus (HSV) infections, human immunodeficiency virus (HIV) infection, hepatitis B and C, and respiratory syncytial virus (RSV) infections.

These medications can be administered orally, intravenously, or topically, depending on the type of viral infection being treated. Some antiviral agents are also used for prophylaxis, or prevention, of certain viral infections.

It is important to note that antiviral agents are not effective against all types of viruses and may have significant side effects. Therefore, it is essential to consult with a healthcare professional before starting any antiviral therapy.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Cerebral toxoplasmosis is a type of toxoplasmosis, which is an infection caused by the Toxoplasma gondii parasite. In cerebral toxoplasmosis, the infection primarily affects the brain, leading to inflammation and the formation of lesions or abscesses in the brain tissue.

This condition is most commonly observed in individuals with weakened immune systems, such as those living with HIV/AIDS, receiving immunosuppressive therapy after organ transplantation, or having other conditions that compromise their immune function. The infection can cause a range of neurological symptoms, including headaches, seizures, confusion, memory loss, poor coordination, and in severe cases, coma or even death. Early diagnosis and treatment with appropriate antiparasitic medications are crucial to manage the infection and prevent complications.

Regulatory sequences in nucleic acid refer to specific DNA or RNA segments that control the spatial and temporal expression of genes without encoding proteins. They are crucial for the proper functioning of cells as they regulate various cellular processes such as transcription, translation, mRNA stability, and localization. Regulatory sequences can be found in both coding and non-coding regions of DNA or RNA.

Some common types of regulatory sequences in nucleic acid include:

1. Promoters: DNA sequences typically located upstream of the gene that provide a binding site for RNA polymerase and transcription factors to initiate transcription.
2. Enhancers: DNA sequences, often located at a distance from the gene, that enhance transcription by binding to specific transcription factors and increasing the recruitment of RNA polymerase.
3. Silencers: DNA sequences that repress transcription by binding to specific proteins that inhibit the recruitment of RNA polymerase or promote chromatin compaction.
4. Intron splice sites: Specific nucleotide sequences within introns (non-coding regions) that mark the boundaries between exons (coding regions) and are essential for correct splicing of pre-mRNA.
5. 5' untranslated regions (UTRs): Regions located at the 5' end of an mRNA molecule that contain regulatory elements affecting translation efficiency, stability, and localization.
6. 3' untranslated regions (UTRs): Regions located at the 3' end of an mRNA molecule that contain regulatory elements influencing translation termination, stability, and localization.
7. miRNA target sites: Specific sequences in mRNAs that bind to microRNAs (miRNAs) leading to translational repression or degradation of the target mRNA.

A CD4 lymphocyte count is a laboratory test that measures the number of CD4 T-cells (also known as CD4+ T-cells or helper T-cells) in a sample of blood. CD4 cells are a type of white blood cell that plays a crucial role in the body's immune response, particularly in fighting off infections caused by viruses and other pathogens.

CD4 cells express a protein on their surface called the CD4 receptor, which is used by human immunodeficiency virus (HIV) to infect and destroy these cells. As a result, people with HIV infection or AIDS often have low CD4 lymphocyte counts, which can make them more susceptible to opportunistic infections and other complications.

A normal CD4 lymphocyte count ranges from 500 to 1,200 cells per cubic millimeter of blood (cells/mm3) in healthy adults. A lower than normal CD4 count is often used as a marker for the progression of HIV infection and the development of AIDS. CD4 counts are typically monitored over time to assess the effectiveness of antiretroviral therapy (ART) and to guide clinical decision-making regarding the need for additional interventions, such as prophylaxis against opportunistic infections.

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Adang L, Berger J (2015). "Progressive Multifocal Leukoencephalopathy". F1000Research. 4: 1424. doi:10.12688/f1000research. ... JC virus with progressive multifocal leukoencephalopathy, and Merkel cell virus (MCV) with Merkel cell cancer. SV40 replicates ... JC virus with progressive multifocal leukoencephalopathy, and Merkel cell virus with Merkel cell cancer. Polyomaviruses are non ... In cases of progressive multifocal leucoencephalopathy (PML), a cross-reactive antibody to SV40 T antigen (commonly Pab419) is ...
Human polyomavirus 2 (also known as JC virus) is known to cause progressive multifocal leukoencephalopathy (PML). Human ... Bohra C, Sokol L, Dalia S (2017-11-01). "Progressive Multifocal Leukoencephalopathy and Monoclonal Antibodies: A Review". ... Kartau M, Sipilä JO, Auvinen E, Palomäki M, Verkkoniemi-Ahola A (2019-12-02). "Progressive Multifocal Leukoencephalopathy: ...
Major EO (2010). "Progressive multifocal leukoencephalopathy in patients on immunomodulatory therapies". Annual Review of ... Berger JR, Houff SA, Major EO (2009). "Monoclonal antibodies and progressive multifocal leukoencephalopathy". mAbs. 1 (6): 583- ... invasive fungal disease and progressive multifocal leukoencephalopathy (PML), a brain infection caused by reactivation of ...
Gheuens, Sarah; Wüthrich, Christian; Koralnik, Igor J. (2013). "Progressive Multifocal Leukoencephalopathy: Why Gray and White ... the agent of progressive multifocal leukoencephalopathy (PML), under the mentorship of Norman Letvin, MD, professor of medicine ... which causes progressive multifocal leukoencephalopathy (PML), a disease of the central nervous system that occurs in ... Progressive multifocal leukoencephalopathy: Epidemiology, clinical manifestations, and diagnosis. up-to-date Wolters Kluwer ...
"Progressive multifocal leukoencephalopathy in patients with sarcoidosis". Neurology. 82 (15): 1307-13. doi:10.1212/WNL. ... Overall, about 50% develop permanent pulmonary abnormalities, and 5 to 15% have progressive fibrosis of the lung parenchyma. ... progressive disease; these patterns do not represent consecutive "stages" of sarcoidosis. Thus, except for epidemiologic ...
Segarra-Newnham M, Vodolo KM (June 2001). "Use of cidofovir in progressive multifocal leukoencephalopathy". The Annals of ... Cidofovir has also been investigated as a treatment for progressive multifocal leukoencephalopathy with successful case reports ...
No deaths from progressive multifocal leukoencephalopathy have been linked to natalizumab when it was not combined with other ... July 2005). "Progressive multifocal leukoencephalopathy after natalizumab therapy for Crohn's disease". The New England Journal ... July 2005). "Progressive multifocal leukoencephalopathy after natalizumab therapy for Crohn's disease". The New England Journal ... Langer-Gould A, Atlas SW, Green AJ, Bollen AW, Pelletier D (July 2005). "Progressive multifocal leukoencephalopathy in a ...
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Berger, Joseph (2003). "Progressive Multifocal Leukoencephalopathy in Acquired Immunodeficiency Syndrome: Explaining the High ... Berger, JR; Houff, S (2006). "Progressive multifocal leukoencephalopathy: Lessons from AIDS and natalizumab". Neurological ... "Progressive multifocal leukoencephalopathy associated with human immunodeficiency virus infection. A review of the literature ... for his research interests in progressive multifocal leukoencephalopathy (PML), the neurological complications of HIV/AIDS, ...
No cases of progressive multifocal leukoencephalopathy were noted. Davenport RJ, Munday JR (July 2007). "Alpha4-integrin ...
In June 2010, the first case report appeared of a progressive multifocal leukoencephalopathy being successfully treated with ... "Mefloquine in the treatment of progressive multifocal leukoencephalopathy". Journal of Neurology, Neurosurgery, and Psychiatry ...
Kleinschmidt-Demasters, B.K.; Tyler, Kenneth L. (2005). "Progressive Multifocal Leukoencephalopathy Complicating Treatment with ... "Progressive Multifocal Leukoencephalopathy in a Patient Treated with Natalizumab". New England Journal of Medicine. 353 (4): ... Also associated with a rare but serious risk of multifocal leukoencephalopathy (brain infection leading to death or severe ...
Progressive Multifocal Leukoencephalopathy in HIV at eMedicine Theodoropoulos, G., Panoussopoulos, D., Papaconstantinou, I., ... In the brain, it causes the often fatal progressive multifocal leukoencephalopathy, or PML, by destroying oligodendrocytes. ... "Adcetris (brentuximab vedotin): Drug Safety Communication-Progressive Multifocal Leukoencephalopathy and Pulmonary Toxicity". U ... with progressive multifocal leukoencephalopathy (PML). The virus causes PML and other diseases only in cases of ...
This is a viral infection known as progressive multifocal leukoencephalopathy; it attacks the brain and is usually fatal. ... Other serious side effects include an increased risk of cancer, progressive multifocal leukoencephalopathy, anemia, and ...
"Pseudobulbar palsy and affect in a case of progressive multifocal leukoencephalopathy". The Journal of Neuropsychiatry and ... artery of percheron infarct Progressive supranuclear palsy Amyotrophic lateral sclerosis Parkinson's disease and related ...
Repetitive verbal behaviors in free conversation with a person with progressive multifocal leukoencephalopathy. pp. 5, 8. ISBN ... and progressive supranuclear palsy. Such degradation can occur in the substantia nigra where decreased dopamine production ... most commonly in Tourette syndrome and may be present in neurodegenerative disorders like Alzheimer's disease and progressive ...
In 2009, voluntary U.S. market withdrawal after reports of progressive multifocal leukoencephalopathy. 2004: Avastin ( ... and primary progressive multiple sclerosis (PPMS). The PPMS form of the disease previously had no approved treatments. 2017: ...
... has two black box warnings: hepatitis B reactivation and progressive multifocal leukoencephalopathy. In the ...
At least three cases of progressive multifocal leukoencephalopathy had also occurred as of 2015. Fingolimod has also been known ... A rare brain infection that usually leads to death or severe disability, called progressive multifocal leukoencephalopathy (PML ... Its effect in those with primary progressive MS is not clear. It may also be used in chronic inflammatory demyelinating ...
However, because of potential risk of progressive multifocal leukoencephalopathy it is not usually used. Vedolizumab (anti-α4β7 ...
Progressive multifocal leukoencephalopathy in patients treated with fumaric acid esters: a review of 19 cases. J Neurol. 2017; ... Other adverse events include progressive multifocal leukoencephalopathy (PML) and Fanconi syndrome, which are considered rare. ...
The couple divorced after Drake's wife developed AIDS and progressive multifocal leukoencephalopathy, causing behavioral ...
He was eventually flown to Miami, and was diagnosed with progressive multifocal leukoencephalopathy, or PML. He received a ...
Progressive multifocal leukoencephalopathy and Creutzfeldt-Jakob disease have also been found to cause this kind of damage. ... More rarely, cases of progressive Bálint's syndrome have been found in degenerative disorders such as Alzheimer's disease or ...
Neuroinflammation Normal pressure hydrocephalus Hydrocephalus Progressive multifocal leukoencephalopathy Vascular dementia ...
... which caused progressive multifocal leukoencephalopathy. Robert Racic was born on 8 January 1964 and grew up in Melbourne. At ...
The risk of progressive multifocal leukoencephalopathy, a disease caused by viral infection of the brain, is also increased. An ... and active secondary progressive disease in adults or for the treatment of primary progressive MS in adults. It is administered ... It is the first FDA-approved treatment for the primary progressive form. When the FDA approved the drug, it required Roche to ... In February, 2016 the FDA granted Breakthrough Therapy Designation for primary progressive multiple sclerosis. On March 28, ...
Polyomaviruses may cause progressive multifocal leukoencephalopathy (JC virus) and polyomavirus-associated nephropathy, ...
... and Role in Virus Replication of a JC Virus Quasispecies in Patients with Progressive Multifocal Leukoencephalopathy". Journal ...
Progressive multifocal leukoencephalopathy (PML) is a rare and often fatal viral disease characterized by progressive damage (- ... Berger, Joseph (2003). "Progressive multifocal leukoencephalopathy in acquired immunodeficiency syndrome: explaining the high ... "Progressive multifocal leukoencephalopathy , Radiology Reference Article , Radiopaedia.org". Radiopaedia. Retrieved 2019-03-09 ... Segarra-Newnham, Marisel; Vodolo, Kristen M (June 2001). "Use of cidofovir in progressive multifocal leukoencephalopathy". Ann ...
Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the CNS characterized by widespread lesions due ... encoded search term (Progressive Multifocal Leukoencephalopathy in HIV) and Progressive Multifocal Leukoencephalopathy in HIV ... Progressive Multifocal Leukeoncephalopathy Consortium. Progressive multifocal leukoencephalopathy: current treatment options ... In a patient with steadily progressive focal neurologic deficits consistent with progressive multifocal leukoencephalopathy ( ...
Progressive multifocal leukoencephalopathy (PML) is a rare brain disease caused by reactivation of the JC virus. Herein, a case ... Progressive multifocal leukoencephalopathy (PML) is a rare brain disease caused by reactivation of the JC virus. Herein, a case ... Progressive multifocal leukoencephalopathy following rituximab treatment in a patient with rheumatoid arthritis Arthritis Rheum ... Leukoencephalopathy, Progressive Multifocal / chemically induced* * Leukoencephalopathy, Progressive Multifocal / diagnosis * ...
Low Signals on T2* and SWI Sequences in Patients with MS with Progressive Multifocal Leukoencephalopathy. P. Labauge, C. Carra- ... Use of quantitative susceptibility mapping (QSM) in progressive multifocal leukoencephalopathy. J Neuroradiol 2015 Oct 13. [ ... Low Signals on T2* and SWI Sequences in Patients with MS with Progressive Multifocal Leukoencephalopathy ... Low Signals on T2* and SWI Sequences in Patients with MS with Progressive Multifocal Leukoencephalopathy ...
Progressive multifocal leukoencephalopathy 10 years following transplant: 5HT receptor antagonism as an adjunct to immune ... Progressive multifocal leukoencephalopathy 10 years following transplant: 5HT receptor antagonism as an adjunct to immune ... Progressive multifocal leukoencephalopathy 10 years following transplant: 5HT receptor antagonism as an adjunct to immune ...
Progressive Multifocal Leukoencephalopathy (PML) - Etiology, pathophysiology, symptoms, signs, diagnosis & prognosis from the ... Progressive multifocal leukoencephalopathy is suspected in patients with unexplained progressive brain dysfunction, ... 2 Treatment references Progressive multifocal leukoencephalopathy (PML) is caused by reactivation of the JC virus. The disease ... Progressive multifocal leukoencephalopathy (PML) is caused by reactivation of the JC virus. The disease usually occurs in ...
Discover the impact of Progressive Multifocal Leukoencephalopathy caused by the JC virus. Explore potential treatments and risk ... Progressive Multifocal Leukoencephalopathy (PML) is a disease in which a virus ( polymaveris JC) attacks and deteriorates the ...
Progressive multifocal leukoencephalopathy. This is a rare viral condition that affects the brain and spinal cord. It ...
Retrieved from "https://www.wikem.org/w/index.php?title=Progressive_multifocal_leukoencephalopathy&oldid=231647" ...
Overview of common imaging features found with Progressive Multifocal Leukoencephalopathy (PML), characteristic pathologic ... Progressive Multifocal Leukoencephalopathy Free Open Table of Contents: Progressive Multifocal Leukoencephalopathy *Description ... Progressive multifocal leukoencephalopathy in AIDS: are there any MR findings useful to patient management and predictive of ... For more information, please see the corresponding chapter in Radiopaedia and the Progressive Multifocal Leukoencephalopathy ...
PML is a rare and often fatal neurologic disease marked by progressive, immune-mediated, multifocal damage to the white matter ... Retrieved from "https://ccmdb.kuality.ca/index.php?title=Progressive_Multifocal_Leukoencephalopathy_(PML)&oldid=160341" ...
Progressive Multifocal Leukoencephalopathy (PML). PML is a rapidly progressive infection of the central nervous system caused ... RISK OF PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY (PML). *RAPTIVA (efalizumab) increases the risk for PML, a rapidly ... Progressive Multifocal Leukoencephalopathy (PML). PML is a serious brain infection caused by a virus. PML results in death or ... Progressive Multifocal Leukoencephalopathy (PML). See "What is the most important information I should know about RAPTIVA ( ...
Progressive Multifocal Leukoencephalopathy (PML). Progressive multifocal leukoencephalopathy (PML), including fatal cases, have ... Progressive Multifocal Leukoencephalopathy [see WARNINGS AND PRECAUTIONS]. *Anaphylaxis and Infusion-Related Reactions [see ... Infections and infestations: Pneumocystis jiroveci pneumonia, progressive multifocal leukoencephalopathy (PML).. Respiratory, ... Progressive Multifocal Leukoencephalopathy (PML). Inform patients to immediately contact their healthcare provider if they ...
Progressive Multifocal Leukoencephalopathy (PML) Progressive Multifocal Leukoencephalopathy (PML), including fatal PML, can ... Progressive multifocal leukoencephalopathy [see Warnings and Precautions (5.4)] * Tumor lysis syndrome [see Warnings and ... Progressive Multifocal Leukoencephalopathy (PML). PML is a rare, serious brain infection caused by a virus that can happen in ... 5.4 Progressive Multifocal Leukoencephalopathy (PML). JC virus infection resulting in PML and death can occur in rituximab ...
Progressive multifocal leukoencephalopathy (PML) is a fatal, rare viral infection of the brain that leads to demyelination and ... and presented 6 months later with progressive neurologic symptoms of behavioral changes, dysarthria, gait difficulty and left ...
Progressive multifocal leukoencephalopathy (PML) is a rapidly progressive demyelinating disease caused by the reactivation of ... Progressive multifocal leukoencephalopathy limited to the posterior fossa. Neurology Asia, 15 (3). pp. 283-286. ISSN 1823-6138 ... We report a case of AIDS associated PML presenting with progressive cerebellar symptoms, with the unusual feature of imaging ...
Promising Results Published for Pembrolizumab to Treat Progressive Multifocal Leukoencephalopathy. Tuesday, April 16, 2019 ... for treatment of progressive multifocal leukoencephalopathy (PML), caused by the JC virus. Of the 8 individuals with PML who ...
5.3 Progressive Multifocal Leukoencephalopathy (PML) Progressive multifocal leukoencephalopathy (PML), including fatal cases, ... 5.3 Progressive Multifocal Leukoencephalopathy (PML) 5.4 Anaphylaxis and Infusion Reactions 5.5 Tumor Lysis Syndrome 5.6 Skin ... Progressive Multifocal Leukoencephalopathy [see Warnings and Precautions ( 5.3)] *Anaphylaxis and Infusion Reactions [see ... Progressive Multifocal Leukoencephalopathy (PML) Inform patients to immediately contact their healthcare provider if they ...
T1 - Asymptomatic Course and Resolution of Progressive Multifocal Leukoencephalopathy (PML) During Natalizumab Therapy with Pre ... Asymptomatic Course and Resolution of Progressive Multifocal Leukoencephalopathy (PML) During Natalizumab Therapy with Pre- ... Asymptomatic Course and Resolution of Progressive Multifocal Leukoencephalopathy (PML) During Natalizumab Therapy with Pre- ... Asymptomatic Course and Resolution of Progressive Multifocal Leukoencephalopathy (PML) During Natalizumab Therapy with Pre- ...
1: Progressive Multifocal Leukoencephalopathy (PML) Progressive multifocal leukoencephalopathy (PML) is a neurological disorder ... The term progressive in PML means that the disease continues to get worse and often leads to serious brain damage. The term ... The term leukoencephalopathy means that the disease affects mainly the white matter of the brain or myelin, although there ... The loss of motor neurons leads to progressive muscle weakness and muscle wasting (atrophy) in muscles closest to the trunk of ...
Journal issues > Issue 7, November 2016 > Progressive multifocal leukoencephalopathy mimicking cerebral metastases in a patient ... Progressive multifocal leukoencephalopathy mimicking cerebral metastases in a patient treated for nasopharyngeal carcinoma. By ... Progressive multifocal leukoencephalopathy is a rare demyelinating condition caused by reactivated JC polyomavirus. This ...
Progressive Multifocal Leukoencephalopathy: Risk Factors, Management Strategies and Prognosis. $130.00. Select options ...
Progressive multifocal leukoencephalopathy. Salmonella septicemia, recurrent. Toxoplasmosis of brain, onset at age ,1 month ...
Progressive Multifocal Leukoencephalopathy (PML) is a devastating diagnosis. It is similar to ALS and other progressive ...
progressive multifocal leukoencephalopathy. *herpes infection that may raise the likelihood of an infection of the brain or an ... progressive multifocal leukoencephalopathy, a rare brain infection that is usually fatal or results in severe disability ...
Progressive multifocal leukoencephalopathy e. Systemic lymphoma, with advanced HIV disease and partial response to chemotherapy ...
Progressive multifocal leukoencephalopathy and use of mycophenolate mofetil after kidney transplantation. Robert T. Neff, Frank ... Progressive multifocal leukoencephalopathy and use of mycophenolate mofetil after kidney transplantation. In: Transplantation. ... Progressive multifocal leukoencephalopathy and use of mycophenolate mofetil after kidney transplantation. / Neff, Robert T.; ... Progressive multifocal leukoencephalopathy and use of mycophenolate mofetil after kidney transplantation. Transplantation. 2008 ...
  • Merck, Kenilworth, NJ) for treatment of progressive multifocal leukoencephalopathy (PML), caused by the JC virus. (practicalneurology.com)
  • Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system (CNS) characterized by widespread lesions due to infection of oligodendrocytes by JC virus, a ubiquitous human polyomavirus estimated to latently infect the kidneys of 50% of adults. (medscape.com)
  • RAPTIVA (efalizumab) increases the risk for PML, a rapidly progressive viral infection of the central nervous system that has no known treatment and that leads to death or severe disability. (rxlist.com)
  • Progressive multifocal leukoencephalopathy (PML) is a fatal, rare viral infection of the brain that leads to demyelination and neuronal loss. (pairscongress.com)
  • Progressive multifocal leucoencephalopathy (PML) is a rare and often fatal opportunistic infection that has been well reported in patients with rheumatic diseases. (bmj.com)
  • Progressive multifocal leucoencephalopathy (PML) is a rare opportunistic infection of the central nervous system (CNS) encountered in immunosuppressed patients that until recently was primarily the concern of doctors caring for patients with HIV infection, cancer and organ transplants. (bmj.com)
  • Researchers have developed new insight into a rare but deadly brain infection, called progressive multifocal leukoencephalopathy. (sciencedaily.com)
  • PML results in subacute and progressive demyelination in the central nervous system, multifocal neurologic deficits, and death, usually within 9 months. (msdmanuals.com)
  • PML is a rare and often fatal neurologic disease marked by progressive, immune-mediated, multifocal damage to the white matter of the brain. (kuality.ca)
  • She completed 6 cycles of R-CHOP therapy (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone), and presented 6 months later with progressive neurologic symptoms of behavioral changes, dysarthria, gait difficulty and left sided weakness. (pairscongress.com)
  • Patients with SPMS present with features of progressive neurologic disability, with or without clinically overt relapses, and insidious disease progression. (medscape.com)
  • [ 1 , 2 ] Approximately 15% of patients with MS experience a primary progressive course from onset, either without preceding relapses (known as primary progressive multiple sclerosis [PPMS]) or with superimposed neurologic events, known as progressive relapsing MS. (medscape.com)
  • Progressive multifocal leukoencephalopathy (PML) is caused by reactivation of the endemic JC polyomavirus. (medscape.com)
  • Progressive multifocal leukoencephalopathy (PML) is a rare brain disease caused by reactivation of the JC virus. (nih.gov)
  • Progressive multifocal leukoencephalopathy (PML) is a rapidly progressive demyelinating disease caused by the reactivation of JC papova virus usually in immunocompromised hosts. (um.edu.my)
  • Progressive Multifocal Leukoencephalopathy (PML) is a devastating diagnosis. (searcylaw.com)
  • Progressive multifocal leukoencephalopathy (PML) is a rare and often fatal viral disease characterized by progressive damage (-pathy) or inflammation of the white matter (leuko-) of the brain (-encephalo-) at multiple locations (multifocal). (wikipedia.org)
  • Progressive Multifocal Leukoencephalopathy associated to treatment with natalizumab in Mexican patient Multiple Sclerosis. (nel.edu)
  • Quiñones-Aguilar S, Sauri-Suárez S, Alcaraz-Estrada S, García S. Progressive Multifocal Leukoencephalopathy associated to treatment with natalizumab in Mexican patient Multiple Sclerosis. (nel.edu)
  • Progressive multifocal leukoencephalopathy in AIDS: are there any MR findings useful to patient management and predictive of patient survival? (neurosurgicalatlas.com)
  • 2) We report a case of AIDS associated PML presenting with progressive cerebellar symptoms, with the unusual feature of imaging abnormalities limited to the posterior fossa. (um.edu.my)
  • Conventional viruses produce slow virus diseases such as SUBACUTE SCLEROSING PANENCEPHALITIS, progressive multifocal leukoencephalopathy (LEUKOENCEPHALOPATHY, PROGRESSIVE MULTIFOCAL), and AIDS. (bvsalud.org)
  • abstract = "Mycophenolate mofetil (MMF) use may be associated with progressive multifocal leukoencephalopathy (PML). (wustl.edu)
  • Multifocal cortical damage produces cognitive impairment in two thirds of patients. (msdmanuals.com)
  • Progressive multifocal leukoencephalopathy (PML): Monitor for new or worsening neurological, cognitive or behavioral signs or symptoms suggestive of PML. (nih.gov)
  • Associated symptoms include progressive deterioration of cognitive abilities (dementia) and loss of acquired motor skills. (howstuffworks.com)
  • Clumsiness may be the first symptom of progressive multifocal leukoencephalopathy. (msdmanuals.com)
  • The term 'leukoencephalopathy' means that the disease affects mainly the white matter of the brain or myelin, although there are some rare cases in which the gray matter neurons is also involved. (howstuffworks.com)
  • Progressive multifocal leukoencephalopathy is a rare demyelinating condition caused by reactivated JC polyomavirus. (bjmo.be)
  • Progressive Multifocal Leukoencephalopathy (PML) is a disease in which a virus ( polymaveris JC) attacks and deteriorates the myelin, which insulates the nerve cells. (memorise.org)
  • The term 'progressive' in PML means that the disease continues to get worse and often leads to serious brain damage. (howstuffworks.com)
  • The term 'multifocal' means that JCV causes disease in multiple parts of the brain. (howstuffworks.com)
  • Progressive multifocal leukoencephalopathy (PML) is a devastating demyelinating disease caused by JC virus (JCV), predominantly affecting patients with impaired cellular immunity . (bvsalud.org)
  • For more information, please see the corresponding chapter in Radiopaedia and the Progressive Multifocal Leukoencephalopathy chapter within the Cerebral Infectious Diseases subvolume in The Neurosurgical Atlas . (neurosurgicalatlas.com)
  • It is similar to ALS and other progressive neurological diseases that slowly rob patients of their mobility and functioning. (searcylaw.com)
  • A handout on this topic is available at http://familydoctor.org/familydoctor/en/diseases-conditions/rheumatoid-arthritis.html . (aafp.org)
  • We read with interest the study by Hodel et al 1 concerning the occurrence of cortex, U-fiber, and basal ganglia low signals found on T2* and SWI sequences in 12 patients with MS with progressive multifocal leukoencephalopathy (PML). (ajnr.org)
  • Progressive multifocal leukoencephalopathy is suspected in patients with unexplained progressive brain dysfunction, particularly in those with depressed cell-mediated immunity. (msdmanuals.com)
  • Progressive multifocal leukoencephalopathy (PML) is a neurological disorder characterized by destruction of the myelin, an oily substance that helps protect nerve cells in the brain and spinal cord, also known as central nervous system (CNS) white matter. (howstuffworks.com)
  • The Phase III fenebrutinib clinical trial program in RMS and primary progressive MS (PPMS) is ongoing. (gene.com)
  • The CD4+ T-lymphocyte coordinates a number of important immunologic functions, and a loss of these functions results in progressive impairment of the immune response. (cdc.gov)
  • Progressive multifocal leukoencephalopathy (PML) resulting in death ( 5.4 , 6.3 ). (drugs.com)
  • Nationwide Laboratory Surveillance of Progressive Multifocal Leukoencephalopathy in Japan: Fiscal Years 2011-2020. (bvsalud.org)
  • Progressive Multifocal Leukoencephalopathy: Current Insights. (nih.gov)
  • A diagnosis of PML can be made following brain biopsy or by combining observations of a progressive course of the disease, consistent white matter lesions visible on a magnetic resonance imaging (MRI) scan, and the detection of the JC virus in spinal fluid. (nih.gov)
  • She was diagnosed as having progressive multifocal leukoencephalopathy based on characteristic magnetic resonance imaging lesions after 27 infusions of natalizumab. (medscape.com)
  • Brain magnetic resonance imaging (MRI) showed T2-weighted hyperintense, nonenhancing, multifocal white matter lesions ( Appendix Figure 1). (cdc.gov)
  • However, 3 weeks after corticosteroid initiation, the patient demonstrated progressive decrease of alertness, new rise of viral load in the CSF, and expansion of PML lesions as shown on brain MRI ( Figure ). (cdc.gov)
  • Progressive Multifocal Leukoencephalopathy Lesions and JC Virus: The Limits and Value of Imaging. (figure1.com)
  • Our case report illustrates that early detection of asymptomatic progressive multifocal leukoencephalopathy and its subsequent treatment resulted in a benign clinical course. (medscape.com)
  • Atezolizumab successfully reinvigorated JC virus immunity in a patient in Belgium with progressive multifocal leukoencephalopathy, as demonstrated by clinical, virologic, and radiologic response to treatment. (cdc.gov)
  • Clinical course and evolution of JC virus load in CSF of 77-year-old patient undergoing atezolizumab therapy for progressive multifocal leukoencephalopathy. (cdc.gov)
  • Understand the effectiveness of portable ultra-low field MRI in diagnosing and monitoring progressive multifocal leukoencephalopathy, highlighting its potential for point-of-care imaging and clinical trials. (nih.gov)
  • Identify key clinical and imaging features of progressive multifocal leukoencephalopathy (PML) and apply current diagnostic criteria. (nih.gov)
  • Clinical Presentation and Disease Course of 37 Consecutive Cases of Progressive Multifocal Leukoencephalopathy (PML) at a German Tertiary-Care Hospital: A Retrospective Observational Study. (inims.de)
  • Dr. Derek Stitt talks with Prof. Clemens Warnke about the clinical presentation of progressive multifocal leukoencephalopathy, its variants, pathogenesis, and current diagnostic approaches. (neurology.org)
  • Progressive multifocal leukoencephalopathy (PML) is caused by reactivation of the endemic JC polyomavirus. (medscape.com)
  • JC, BK, and other polyomaviruses: progressive multifocal leukoencephalopathy (PML). (medlineplus.gov)
  • HIV/AIDS was historically the most common risk factor, although clinicians should maintain a high degree of suspicion when any immunosuppressed patient (leukemia/lymphoma, chemotherapy, post-transplant, immunotherapies like natalizumab), presents with unusual or progressive neurological findings. (figure1.com)
  • We report the development of asymptomatic progressive multifocal leukoencephalopathy in a patient with multiple sclerosis on natalizumab therapy. (medscape.com)
  • In consideration of the additional small number of cases of asymptomatic progressive multifocal leukoencephalopathy that have been reported, we conclude that routine magnetic resonance imaging surveillance is important for patients with multiple sclerosis who are at high risk for developing natalizumab-associated progressive multifocal leukoencephalopathy. (medscape.com)
  • Magnetic resonance imaging pattern in natalizumab-associated progressive multifocal leukoencephalopathy. (msdiscovery.org)
  • Patients on natalizumab who become John Cunningham Virus seropositive are at risk for progressive multifocal leukoencephalopathy (PML). (clevelandclinic.org)
  • In addition, there is currently no available treatment for the often-fatal disease caused by JCV: Progressive Multifocal Leukoencephalopathy. (nih.gov)
  • Background: Progressive multifocal leukoencephalopathy (PML) caused by JCV is a rare but frequently fatal disease of the central nervous system, usually affecting immunocompromised individuals. (inims.de)
  • The human polyomavirus JC (JCPyV) is the causative agent of the fatal demyelinating disease progressive multifocal leukoencephalopathy (PML). (hawaii.edu)
  • Progressive Multifocal Leukoencephalopathy in a HIV-Negative Patient with Small Lymphocytic Leukemia following Treatment with Rituximab. (nih.gov)
  • The patient is diagnosed with progressive multifocal leukoencephalopathy (PML). (figure1.com)
  • Genentech and The U.S. Food and Drug Administration, the American counterpart to the Saudi Food and Drug Authority (SFDA) notified healthcare professionals about a third case of progressive multifocal leukoencephalopathy [PML], the first case of PML in a patient with rheumatoid arthritis [RA] treated with rituximab who has not previously received treatment with a TNF antagonist. (gov.sa)
  • Progressive multifocal leukoencephalopathy in a minimally immunosuppressed patient with systemic lupus erythematosus treated with dapsone. (nih.gov)
  • Clumsiness may be the first symptom of progressive multifocal leukoencephalopathy. (msdmanuals.com)
  • These infections are what causes PML, which can lead to a variety of symptoms including clumsiness, progressive weakness, and changes in vision, speech, and sometimes personality. (nih.gov)
  • Treatment of progressive multifocal leukoencephalopathy is mainly supportive. (msdmanuals.com)
  • recurrent or progressive* CLL that has responded to previous treatment and may benefit from extended treatment. (medicalnewstoday.com)
  • Ocrevus (ocrelizumab) injection is aCD20-directed cytolytic antibody indicated for the treatment of patients with relapsing or primary progressive forms of multiple sclerosis . (rxlist.com)
  • Advances in Treatment of Progressive Multifocal Leukoencephalopathy. (nih.gov)
  • Treatment of Progressive Multifocal Leukoencephalopathy with Pembrolizumab. (nih.gov)
  • Progressive multifocal leukoencephalopathy is suspected in patients with unexplained progressive brain dysfunction, particularly in those with depressed cell-mediated immunity. (msdmanuals.com)
  • Progressive multifocal leukoencephalopathy (PML) is a devastating infectious disease of the brain that is caused by JC virus (JCV) in the context of cellular immunodeficiency. (cdc.gov)
  • Detection of HIV-1 Tat and JCV capsid protein, VP1, in AIDS brain with Progressive Multifocal Leukoencephalopathy. (lsuhsc.edu)
  • A very bad brain problem called progressive multifocal leukoencephalopathy (PML) has happened with this medicine (ibrutinib tablets). (drugs.com)
  • Recent incidents of serious adverse events, like endocarditis 11 , or multifocal leukoencephalopathy 12 in PwMS on DMT highlighted the importance of standardised safety data collection under real-world conditions 13 . (nature.com)
  • Progressive multifocal leukoencephalopathy (PML): Monitor for new or worsening neurological, cognitive or behavioral signs or symptoms suggestive of PML. (drugs.com)
  • Anat Achiron Introduction: MRI activity is less frequent among secondary progressive multiple sclerosis (SPMS) patients. (karger.com)
  • PML is a progressive neurological degenerative syndrome caused by the John Cunningham (JC) virus in immunosuppressed individuals. (allsup.com)
  • In light of the recent Biogen announcements (TOUCH database) showing a significant reduction in progressive multifocal leukoencephalopathy (PML) risk for patients on extended interval dosing (EID), moNATor provides an individual Tysabri concentration level to help guide physicians in decision making regarding optimal dosing intervals. (prweb.com)
  • Biogen's TOUCH database shows a significant reduction in progressive multifocal leukoencephalopathy (PML) risk for patients on extended interval dosing (EID). (prweb.com)
  • is a rare, progressive, demyelinating disease of the central nervous system that usually leads to death or severe disability. (gov.sa)
  • Over time, recovery may be incomplete, leading to progressive decline in function and increased disability. (fda.gov)
  • Her imaging showed multifocal, confluent regions of T2 hyperintensity in the white matter bilaterally, and CSF JCV PCR returned positive. (nih.gov)
  • Here we present the case of a 40-year-old woman with SLE diagnosed with progressive multifocal leukoencephalopathy (PML) on belimumab. (nih.gov)