Anemia, Diamond-Blackfan
Diamond
Ribosomal Proteins
Anemia, Aplastic
Boron
Anemia, Hemolytic
Fanconi Anemia
Blackfan-Diamond anemia and dyserythropoietic anemia presenting with increased nuchal translucency at 12 weeks of gestation. (1/103)
Blackfan-Diamond anemia is a congenital hypoplastic anemia with a birth prevalence of about 1 in 200,000, usually presenting in the first few months of life and commonly associated with cardiac, urogenital and digital anomalies. Congenital dyserythropoietic anemias are a group of rare congenital anemias characterized by ineffective erythropoiesis. We report on two cases of congenital fetal anemia, one with Blackfan-Diamond anemia and one with dyserythropoietic anemia, presenting with increased nuchal translucency at 12 weeks of gestation. (+info)Response of Diamond-Blackfan anemia to metoclopramide: evidence for a role for prolactin in erythropoiesis. (2/103)
A 47-year-old woman with severe macrocytic anemia markedly improved during the second and third trimesters of 3 pregnancies and when breast-feeding her 2 children. Because the serum prolactin level is elevated at these times, we later treated her with metoclopramide (10 mg orally 3 times daily), a medication known to induce prolactin release. Her serum prolactin levels increased from 7 to 133 ng/mL (normal < 20 ng/mL) and hematocrit from 17% to 22% to 35%. With continued therapy (now 10 mg orally daily), her hematocrit has ranged from 30% to 40% for 6 years, although the macrocytosis persists (mean corpuscular volume, 100-112 fL). On the basis of this observation, a pilot study was undertaken of metoclopramide therapy in patients with Diamond-Blackfan anemia who were refractory to low doses of corticosteroids. Fifteen patients were enrolled and 9 completed the planned 16 weeks of therapy. Three individuals responded, suggesting that this therapeutic approach may benefit others. As with the index case, the anemia did not improve until 12 to 15 weeks of therapy had been completed. (+info)Gene transfer improves erythroid development in ribosomal protein S19-deficient Diamond-Blackfan anemia. (3/103)
Diamond-Blackfan anemia (DBA) is a congenital bone marrow failure syndrome characterized by a specific deficiency in erythroid progenitors. Forty percent of the patients are blood transfusion-dependent. Recent reports show that the ribosomal protein S19 (RPS19) gene is mutated in 25% of all patients with DBA. We constructed oncoretroviral vectors containing the RPS19 gene to develop gene therapy for RPS19-deficient DBA. These vectors were used to introduce the RPS19 gene into CD34(+) bone marrow (BM) cells from 4 patients with DBA with RPS19 gene mutations. Overexpression of the RPS19 transgene increased the number of erythroid colonies by almost 3-fold. High expression levels of the RPS19 transgene improved erythroid colony-forming ability substantially whereas low expression levels had no effect. Overexpression of RPS19 had no detrimental effect on granulocyte-macrophage colony formation. Therefore, these findings suggest that gene therapy for RPS19-deficient patients with DBA using viral vectors that express the RPS19 gene is feasible. (+info)Marrow failure. (4/103)
This chapter describes the clinical presentation and molecular basis of two inherited bone marrow failure syndromes, Fanconi anemia (FA), and Diamond-Blackfan anemia (DBA). It also provides an update on diagnostic and therapeutic approaches to bone marrow failure of all types (inherited and acquired) in pediatric patients. In Section I, Dr. Alan D'Andrea reviews the wide range of clinical manifestations of Fanconi anemia. Significant advances have been made in understanding the molecular pathogenesis of FA. On the basis of these advances, new diagnostic assays and treatment options are now available. In Section II, Dr. Niklas Dahl examines the clinical features and molecular pathogenesis of Diamond-Blackfan anemia. The possible links between the RPS19 gene (DBA gene) and the erythropoiesis defect are considered. In Section III, Drs. Eva Guinan and Akiko Shimamura provide an algorithm for the diagnostic evaluation and treatment of children with inherited or acquired aplastic anemia. Through the presentation of a case study of a pediatric patient with bone marrow failure, he provides an overview of the newest tests and treatment options. (+info)Nucleolar localization of RPS19 protein in normal cells and mislocalization due to mutations in the nucleolar localization signals in 2 Diamond-Blackfan anemia patients: potential insights into pathophysiology. (5/103)
Ribosomal protein S19 (RPS19) is frequently mutated in Diamond-Blackfan anemia (DBA), a rare congenital hypoplastic anemia. Recent studies have shown that RPS19 expression decreases during terminal erythroid differentiation. Currently no information is available on the subcellular localization of normal RPS19 and the potential effects of various RPS19 mutations on cellular localization. In the present study, using wild-type and mutant RPS19 cDNA, we explored the subcellular distribution of normal and mutant proteins in a fibroblast cell line (Cos-7 cells). RPS19 was detected primarily in the nucleus, and more specifically in the nucleoli, where RPS19 colocalized with the nucleolar protein nucleolin. Using various N-terminal and C-terminal deletion constructs, we identified 2 nucleolar localization signals (NoSs) in RPS19: the first comprising amino acids Met1 to Arg16 in the NH2-terminus and the second comprising Gly120 to Asn142 in the COOH-terminus. Importantly, 2 mutations identified in DBA patients, Val15Phe and Gly127Gln, each of which localized to 1 of the 2 NoS, failed to localize RPS19 to the nucleolus. In addition to their mislocalization, there was a dramatic decrease in the expression of the 2 mutant proteins compared to the wild type. This decrease in protein expression was specific for the mutant RPS19, since expression of other proteins was normal. The present findings enable us to document the nucleolar localization signals in RPS19 and help define the phenotypic consequences of some mutations in RPS19 in DBA. (+info)Nomimmune hydrops fetalis due to Diamond-Blackfan anemia. (6/103)
We describe case report of a baby with Diamond-Blackfan anemia, who presented as non-immune hydrops fetalis. The diagnosis was confirmed by measurement of red cell adenosine deaminase activity which is increased in Diamond-Blackfan anemia. At 2 years of age he is dependent on small dose of alternate day steroid to maintain his hemoglobin. (+info)Molecular basis of Diamond-Blackfan anemia: new findings from the Italian registry and a review of the literature. (7/103)
BACKGROUND AND OBJECTIVES: Diamond-Blackfan anemia (DBA) is a rare, pure red blood cell aplasia of childhood caused by an intrinsic defect in erythropoietic progenitors. Malformations occur in about 40% of patients. More than half of patients respond to steroids; non-responders need chronic transfusions or stem cell transplantation (SCT). Mutations in the gene encoding ribosomal protein S19 are found in 25% of patients, but the link with erythropoiesis is unclear. A second DBA locus has been found on chromosome 8p22-p23; analysis of genes of the region is in progress. METHODS AND INFORMATION SOURCES: We present clinical and molecular data from 97 Italian DBA patients and a review of the literature. RESULTS AND STATE OF THE ART: We describe five new RPS19 gene mutations: four point mutations and one unbalanced chromosomal translocation. Hematologic findings, malformations and outcome are similar in the RPS19 mutated and the non-mutated groups. No genotype-phenotype correlation has been found so far in RPS19 mutated patients. Our data, however, and a thorough review of literature show a worse outcome (expressed as transfusion dependence) in patients with mutations that completely abolish one allele, i.e. gross chromosomal rearrangements and mutations at the initiation codon. The association of mental retardation with large deletions at the 19q locus points to a contiguous gene syndrome. A recurrent missense mutation (Arg62Trp) is associated with transfusion dependence in eight of the nine reported cases. PERSPECTIVES: Nationwide collaboration and population-based registries recording molecular data are essential for the further dissection of this rare heterogeneous disease and the definition of new therapeutic trials. (+info)Targeted disruption of the ribosomal protein S19 gene is lethal prior to implantation. (8/103)
The ribosomal protein S19 (RPS19) is located in the small (40S) subunit and is one of 79 ribosomal proteins. The gene encoding RPS19 is mutated in approximately 25% of patients with Diamond-Blackfan anemia, which is a rare congenital erythroblastopenia. Affected individuals present with decreased numbers or the absence of erythroid precursors in the bone marrow, and associated malformations of various organs are common. We produced C57BL/6J mice with a targeted disruption of murine Rps19 to study its role in erythropoiesis and development. Mice homozygous for the disrupted Rps19 were not identified as early as the blastocyst stage, indicating a lethal effect. In contrast, mice heterozygous for the disrupted Rps19 allele have normal growth and organ development, including that of the hematopoietic system. Our findings indicate that zygotes which are Rps19(-/-) do not form blastocysts, whereas one normal Rps19 allele in C57BL/6J mice is sufficient to maintain normal ribosomal and possibly extraribosomal functions. (+info)Diamond-Blackfan anemia is a rare, congenital bone marrow failure disorder characterized by a decreased production of red blood cells (erythroblasts) in the bone marrow. This results in a reduced number of circulating red blood cells, leading to anemia and related symptoms such as fatigue, weakness, and pallor. The disorder is typically diagnosed in infancy or early childhood and can also be associated with physical abnormalities.
The exact cause of Diamond-Blackfan anemia is not fully understood, but it is believed to involve genetic mutations that affect the development and function of the bone marrow. In many cases, the disorder is inherited in an autosomal dominant manner, meaning that a child has a 50% chance of inheriting the mutated gene from an affected parent. However, some cases may arise spontaneously due to new genetic mutations.
Treatment for Diamond-Blackfan anemia typically involves regular blood transfusions to maintain adequate red blood cell levels and alleviate symptoms. Corticosteroid therapy may also be used to stimulate red blood cell production in some cases. In severe or refractory cases, stem cell transplantation may be considered as a curative treatment option.
I believe you are asking for a medical explanation or definition of the term "diamond" in a medical context. However, I should clarify that "diamond" is not a commonly used medical term for a specific disease, condition, or diagnostic feature. It's essential to provide more information if it relates to a particular medical concept or usage.
In general, the term "diamond" refers to a clear and colorless form of carbon with a crystalline structure in which each carbon atom is bonded to four other carbon atoms, forming a tetrahedral shape. It's widely known for its use as a valuable gemstone due to its exceptional hardness, brilliance, and fire.
However, there are some tangential medical connections to the term "diamond." For example:
1. Diamond Blackfan anemia (DBA): A rare congenital bone marrow failure disorder characterized by a decrease in red blood cell production. It is named after Drs. Louis Diamond and Kenneth Blackfan, who first described it.
2. Turner syndrome with XY sex chromosomes: A rare genetic condition where an individual has only one functional X chromosome instead of the typical pair (XX) found in females. Occasionally, these individuals may have a Y chromosome fragment, often referred to as "mosaic Turner syndrome with XY cells" or "XY gonadal dysgenesis." In this context, the term "XY" is sometimes metaphorically described as a "genetic male's 'diamond in the rough'" due to its rarity and unique characteristics.
If you have more information about how the term "diamond" is being used in your specific medical context, I would be happy to help further clarify or provide additional details.
Ribosomal proteins are a type of protein that play a crucial role in the structure and function of ribosomes, which are complex molecular machines found within all living cells. Ribosomes are responsible for translating messenger RNA (mRNA) into proteins during the process of protein synthesis.
Ribosomal proteins can be divided into two categories based on their location within the ribosome:
1. Large ribosomal subunit proteins: These proteins are associated with the larger of the two subunits of the ribosome, which is responsible for catalyzing peptide bond formation during protein synthesis.
2. Small ribosomal subunit proteins: These proteins are associated with the smaller of the two subunits of the ribosome, which is responsible for binding to the mRNA and decoding the genetic information it contains.
Ribosomal proteins have a variety of functions, including helping to stabilize the structure of the ribosome, assisting in the binding of substrates and cofactors necessary for protein synthesis, and regulating the activity of the ribosome. Mutations in ribosomal proteins can lead to a variety of human diseases, including developmental disorders, neurological conditions, and cancer.
Anemia is a medical condition characterized by a lower than normal number of red blood cells or lower than normal levels of hemoglobin in the blood. Hemoglobin is an important protein in red blood cells that carries oxygen from the lungs to the rest of the body. Anemia can cause fatigue, weakness, shortness of breath, and a pale complexion because the body's tissues are not getting enough oxygen.
Anemia can be caused by various factors, including nutritional deficiencies (such as iron, vitamin B12, or folate deficiency), blood loss, chronic diseases (such as kidney disease or rheumatoid arthritis), inherited genetic disorders (such as sickle cell anemia or thalassemia), and certain medications.
There are different types of anemia, classified based on the underlying cause, size and shape of red blood cells, and the level of hemoglobin in the blood. Treatment for anemia depends on the underlying cause and may include dietary changes, supplements, medication, or blood transfusions.
Aplastic anemia is a medical condition characterized by pancytopenia (a decrease in all three types of blood cells: red blood cells, white blood cells, and platelets) due to the failure of bone marrow to produce new cells. It is called "aplastic" because the bone marrow becomes hypocellular or "aplastic," meaning it contains few or no blood-forming stem cells.
The condition can be acquired or inherited, with acquired aplastic anemia being more common. Acquired aplastic anemia can result from exposure to toxic chemicals, radiation, drugs, viral infections, or autoimmune disorders. Inherited forms of the disease include Fanconi anemia and dyskeratosis congenita.
Symptoms of aplastic anemia may include fatigue, weakness, shortness of breath, pale skin, easy bruising or bleeding, frequent infections, and fever. Treatment options for aplastic anemia depend on the severity of the condition and its underlying cause. They may include blood transfusions, immunosuppressive therapy, and stem cell transplantation.
Dental high-speed equipment typically refers to the handpiece used in dental procedures that operates at high rotational speeds, often exceeding 100,000 revolutions per minute (RPM). These handpieces are used for cutting and removing tooth structure, such as during cavity preparation or tooth reduction for restorations. They are called "high-speed" to distinguish them from slow-speed handpieces that operate at lower RPMs, typically under 10,000, and are used for procedures like polishing or cutting softer materials. High-speed handpieces are an essential part of modern dental practice, enabling precise and efficient removal of tooth structure while minimizing patient discomfort and procedure time.
Boron is a chemical element with the symbol B and atomic number 5. It is a metalloid that is light-colored, hard, and highly resistant to corrosion. In its crystalline form, boron is nearly as hard as diamond.
In medicine, boron compounds have been studied for their potential therapeutic uses, particularly in the treatment of cancer. For example, boron neutron capture therapy (BNCT) is a type of radiation therapy that involves the use of boron-containing compounds to selectively deliver radiation to cancer cells.
Boron is also an essential micronutrient for plants and some animals, including humans. However, excessive exposure to boron can be toxic to humans and other organisms. Therefore, it is important to maintain appropriate levels of boron in the body and environment.
Hemolytic anemia is a type of anemia that occurs when red blood cells are destroyed (hemolysis) faster than they can be produced. Red blood cells are essential for carrying oxygen throughout the body. When they are destroyed, hemoglobin and other cellular components are released into the bloodstream, which can lead to complications such as kidney damage and gallstones.
Hemolytic anemia can be inherited or acquired. Inherited forms of the condition may result from genetic defects that affect the structure or function of red blood cells. Acquired forms of hemolytic anemia can be caused by various factors, including infections, medications, autoimmune disorders, and certain medical conditions such as cancer or blood disorders.
Symptoms of hemolytic anemia may include fatigue, weakness, shortness of breath, pale skin, jaundice (yellowing of the skin and eyes), dark urine, and a rapid heartbeat. Treatment for hemolytic anemia depends on the underlying cause and may include medications, blood transfusions, or surgery.
Fanconi anemia is a rare, inherited disorder that affects the body's ability to produce healthy blood cells. It is characterized by bone marrow failure, congenital abnormalities, and an increased risk of developing certain types of cancer. The condition is caused by mutations in genes responsible for repairing damaged DNA, leading to chromosomal instability and cell death.
The classic form of Fanconi anemia (type A) is typically diagnosed in childhood and is associated with various physical abnormalities such as short stature, skin pigmentation changes, thumb and radial ray anomalies, kidney and genitourinary malformations, and developmental delays. Other types of Fanconi anemia (B-G) may have different clinical presentations but share the common feature of bone marrow failure and cancer predisposition.
Bone marrow failure in Fanconi anemia results in decreased production of all three types of blood cells: red blood cells, white blood cells, and platelets. This can lead to anemia (low red blood cell count), neutropenia (low white blood cell count), and thrombocytopenia (low platelet count). These conditions increase the risk of infections, fatigue, and bleeding.
Individuals with Fanconi anemia have a significantly higher risk of developing various types of cancer, particularly acute myeloid leukemia (AML) and solid tumors such as squamous cell carcinomas of the head, neck, esophagus, and anogenital region.
Treatment for Fanconi anemia typically involves managing symptoms related to bone marrow failure, such as transfusions, growth factors, and antibiotics. Hematopoietic stem cell transplantation (HSCT) is the only curative treatment option for bone marrow failure but carries risks of its own, including graft-versus-host disease and transplant-related mortality. Regular cancer surveillance is essential due to the increased risk of malignancies in these patients.
Hemolytic anemia, autoimmune is a type of anemia characterized by the premature destruction of red blood cells (RBCs) in which the immune system mistakenly attacks and destroys its own RBCs. This occurs when the body produces autoantibodies that bind to the surface of RBCs, leading to their rupture (hemolysis). The symptoms may include fatigue, weakness, shortness of breath, and dark colored urine. The diagnosis is made through blood tests that measure the number and size of RBCs, reticulocyte count, and the presence of autoantibodies. Treatment typically involves suppressing the immune system with medications such as corticosteroids or immunosuppressive drugs, and sometimes removal of the spleen (splenectomy) may be necessary.