Moraxellaceae
Moraxella (Moraxella) bovis
Moraxella
RNA, Ribosomal, 16S
Acinetobacter baumannii
Acinetobacter
Acinetobacter calcoaceticus
Encyclopedias as Topic
Comparison of Moraxella catarrhalis isolates from children and adults for growth on modified New York City medium and potential virulence factors. (1/97)
Initial studies found that Moraxella catarrhalis isolates from adults that grew on modified New York City medium (MNYC(+)) that contained antibiotics selective for pathogenic neisseriae differed from strains that did not grow on this medium (MNYC(-)) in their potential virulence properties. It was predicted that higher usage of antibiotics to treat respiratory illness in children might result in higher proportions of MNYC(+) isolates if antibiotics were an important selective pressure for this phenotype. Two of 100 adult isolates (2 %) were MNYC(+), compared to 88 of 88 isolates (100 %) from children (P = 0.000). MNYC(+) strains were serum-resistant and bound in higher numbers to HEp-2 cells that were infected with respiratory syncytial virus (RSV). Endotoxin from an MNYC(+) isolate induced significantly higher pro-inflammatory response levels than endotoxin from an MNYC(-) strain. MNYC(-) adult isolates expressed haemagglutinins and bound in lower numbers to RSV-infected cells, but serum resistance was variable. All isolates from children were MNYC(+), serum-resistant and bound in greater numbers to RSV-infected cells. These results indicate that both RSV infection and antibiotic usage select for the MNYC(+) phenotype. (+info)Presumed endocarditis caused by BRO beta-lactamase-producing Moraxella lacunata in an infant with Fallot's tetrad. (2/97)
A case of presumed endocarditis caused by Moraxella lacunata in a 15-month-old male infant with Fallot's tetrad is described. This infection may have occurred as the result of transmission of this organism between the father and his son. This is the first report of BRO beta-lactamase-producing M. lacunata causing presumed endocarditis. (+info)Antigenic relationships of Moraxella bovis isolates recovered from outbreaks of infectious bovine keratoconjunctivitis in Argentina, Brazil, and Uruguay between 1983 and 2000. (3/97)
Cross-reactivity indices (CRIs) of 28 isolates of Moraxella bovis recovered from outbreaks of infectious bovine keratoconjunctivitis in Argentina (A, 11 isolates), Brazil (B, 7), and Uruguay (U, 10) between 1983 and 2000 were estimated. Hyperimmune sera were produced in rabbits and antibody titres determined with each isolate. Isolates showing CRIs3 70 were placed in the same group. Group I had 13 isolates (A, 1; B, 6; U, 6); group II had 6 isolates (A, 4; U, 2); groups III, IV, and V had 2 isolates each, recovered in Argentina; group VI had 2 isolates, from Uruguay; and group VII had 1 isolate, from Brazil. The CRIs3 70 between vaccine strains and isolates recovered before and after 1990 were 58% and 42%, 50% and 50%, and 33% and 67% with vaccine strains 2419, 2358, and 2439, respectively. Isolate 273, from Uruguay, showed CRIs > 70 with 78% of the isolates and is recommended as the vaccine strain. (+info)Moraxella osloensis blood and catheter infections during anticancer chemotherapy: clinical and microbiologic studies of 10 cases. (4/97)
Moraxella osloensis, a gram-negative bacterium that is saprophytic on skin and mucosa, rarely causes infections. Moreover, infections in patients with cancer have not been reported. We describe 10 cases of M. osloensis blood or catheter infections that occurred during anticancer chemotherapy with or without preexisting neutropenia. The organism was identified definitively by sequencing analysis of the 16S ribosomal RNA gene. Fever (up to 39.7 degrees C) with substantial neutrophilia characterized these infections. The infections were monomicrobic for 3 patients and polymicrobic for 7 patients. Nine patients acquired the infection through central venous catheter colonization. The likely sources of the organism were sinusitis (3 cases), bronchitis (1 case), presumed subclinical mucositis from anticancer therapy (4 cases), and cutaneous graft-vs-host disease (2 cases). The infections resolved, without catheter removal, after antibiotic therapy with cell wall-active agents, to which all strains were shown to be susceptible. The M. osloensis strains exhibited significant morphologic variations on gram stain, and sheep blood agar was the preferred culture medium for 9 strains. (+info)Immunization with the truncated adhesin moraxella catarrhalis immunoglobulin D-binding protein (MID764-913) is protective against M. catarrhalis in a mouse model of pulmonary clearance. (5/97)
Most Moraxella catarrhalis isolates express the outer membrane protein MID. In addition to its specific affinity for immunoglobulin D, MID functions as an adhesin and binds to human epithelium. The adhesive part is localized within MID(764-913). Two mid-deficient M. catarrhalis isolates were constructed and examined in a mouse model of pulmonary clearance. M. catarrhalis devoid of MID was cleared more efficiently, compared with the wild-type counterparts. Furthermore, mice immunized with MID(764-913) cleared M. catarrhalis much more efficiently, compared with mice immunized with bovine serum albumin. MID(764-913) is suggested as a promising candidate in a future M. catarrhalis vaccine. (+info)Mucoid nitrate-negative Moraxella nonliquefaciens from three patients with chronic lung disease. (6/97)
Mucoid strains of Moraxella nonliquefaciens were recovered from the sputa of three indigenous Australians with chronic lung disease. These atypical strains failed to reduce nitrate, and one strain produced beta-lactamase. While the mucoid phenotype of M. nonliquefaciens has rarely been reported, the mucoid nitrate-negative biovar has never been previously reported. (+info)Detection rates of bacteria in chronic otitis media with effusion in children. (7/97)
This study was performed to investigate polymerase chain reaction-based detection of bacterial DNA in middle ear fluid and assess the correlation between the PCR-positive rate with several factors associated with middle ear effusion. The purpose was to gain a further understanding of bacterial infection as a major cause of otitis media with effusion. Of the 278 specimens of middle ear fluid, 39 (14%) tested positive by ordinary culture. The overall detection rate of bacterial DNA using the PCR method was 36.7% for middle ear effusion, and bacterial DNA detection rates of Hemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis in the middle ear effusion were 29.1%, 4.7% and 10.8%, respectively. The bacterial DNA detection rate was higher in ears with a history of acute otitis media than those without the history. High detection rates were observed in patients younger than 48 months who have had a higher tendency to present with acute otitis media. We concluded that PCR is a more sensitive method for the detection of bacteria in middle ear effusion than ordinary culture, and acute otitis media is a major contributor to the pathogenesis of otitis media with effusion. (+info)Moraxella catarrhalis coaggregates with Streptococcus pyogenes and modulates interactions of S. pyogenes with human epithelial cells. (8/97)
The pathogens Streptococcus pyogenes and Moraxella catarrhalis colonize overlapping regions of the human nasopharynx. We have found that M. catarrhalis can dramatically increase S. pyogenes adherence to human epithelial cells and that species-specific coaggregation of these bacteria correlates with this enhanced adherence. (+info)Moraxellaceae is a family of Gram-negative, aerobic or facultatively anaerobic bacteria within the class Gammaproteobacteria. The bacteria in this family are typically non-motile and have a polar flagellum or are non-flagellated. They are known to be found in various environments such as soil, water, and the mucous membranes of animals. Some genera within this family include Moraxella, Acinetobacter, and Psychrobacter. These bacteria can cause a variety of infections in humans, ranging from respiratory tract infections to bacteremia and meningitis, particularly in individuals with weakened immune systems.
Moraxellaceae is a family of Gram-negative, aerobic or facultatively anaerobic bacteria that are commonly found in the environment and on the mucosal surfaces of humans and animals. Infections caused by Moraxellaceae are relatively rare but can occur, particularly in individuals with weakened immune systems.
Two genera within this family, Moraxella and Acinetobacter, are most commonly associated with human infections. Moraxella catarrhalis is a leading cause of respiratory tract infections such as bronchitis, otitis media (middle ear infection), and sinusitis, particularly in children and the elderly. It can also cause conjunctivitis (pink eye) and pneumonia.
Acinetobacter species, on the other hand, are often found in soil and water and can colonize the skin and mucous membranes of humans without causing harm. However, they can become opportunistic pathogens in hospital settings, causing a range of infections such as pneumonia, bloodstream infections, wound infections, and meningitis, particularly in critically ill or immunocompromised patients.
Infections caused by Moraxellaceae can be treated with antibiotics, but the increasing prevalence of antibiotic-resistant strains is a growing concern. Proper infection control measures, such as hand hygiene and environmental cleaning, are essential to prevent the spread of these infections in healthcare settings.
"Moraxella" is a genus of gram-negative, aerobic bacteria that are commonly found on the mucous membranes of humans and animals. They are non-motile and catalase-positive. Some species of Moraxella can cause infections in humans, such as M. catarrhalis, which is a common cause of respiratory tract infections like bronchitis and otitis media (middle ear infection) in children. Another species, M. nonliquefaciens, can be found on the skin and mucous membranes of humans and animals, but it's not considered to be pathogenic.
It is worth noting that Moraxella genus was previously classified under the name Neisseria, but based on genetic and biochemical evidence, they are now considered separate genera.
Ribosomal RNA (rRNA) is a type of RNA that combines with proteins to form ribosomes, which are complex structures inside cells where protein synthesis occurs. The "16S" refers to the sedimentation coefficient of the rRNA molecule, which is a measure of its size and shape. In particular, 16S rRNA is a component of the smaller subunit of the prokaryotic ribosome (found in bacteria and archaea), and is often used as a molecular marker for identifying and classifying these organisms due to its relative stability and conservation among species. The sequence of 16S rRNA can be compared across different species to determine their evolutionary relationships and taxonomic positions.
'Acinetobacter baumannii' is a gram-negative, aerobic, coccobacillus-shaped bacterium that is commonly found in the environment, including water, soil, and healthcare settings. It is known to cause various types of infections in humans, particularly in hospitalized patients or those with weakened immune systems.
This bacterium can cause a range of infections, such as pneumonia, bloodstream infections, meningitis, and wound infections. 'Acinetobacter baumannii' is often resistant to multiple antibiotics, making it difficult to treat the resulting infections. This has led to its classification as a "superbug" or a multidrug-resistant organism (MDRO).
The medical community continues to research and develop new strategies to prevent and treat infections caused by 'Acinetobacter baumannii' and other antibiotic-resistant bacteria.
Acinetobacter infections are caused by bacteria that can be found in various environments, such as soil, water, and healthcare facilities. These bacteria can cause a range of illnesses, from mild skin infections to serious respiratory and bloodstream infections. They are often resistant to multiple antibiotics, making them difficult to treat.
Acinetobacter baumannii is the species most commonly associated with human infection. It is known for its ability to survive on dry surfaces for extended periods of time, which can contribute to its spread in healthcare settings. Infections caused by Acinetobacter are a particular concern in critically ill patients, such as those in intensive care units, and in individuals with weakened immune systems.
Symptoms of an Acinetobacter infection depend on the site of infection but may include fever, cough, shortness of breath, wound drainage, or skin redness or swelling. Treatment typically involves the use of antibiotics that are still effective against the bacteria, which can be determined through laboratory testing. In some cases, infection control measures, such as contact precautions and environmental cleaning, may also be necessary to prevent the spread of Acinetobacter in healthcare settings.
'Acinetobacter' is a genus of gram-negative, aerobic bacteria that are commonly found in the environment, including water, soil, and healthcare settings. They are known for their ability to survive in a wide range of temperatures and pH levels, as well as their resistance to many antibiotics.
Some species of Acinetobacter can cause healthcare-associated infections, particularly in patients who are hospitalized, have weakened immune systems, or have been exposed to medical devices such as ventilators or catheters. These infections can include pneumonia, bloodstream infections, wound infections, and meningitis.
Acinetobacter baumannii is one of the most common species associated with human infection and is often resistant to multiple antibiotics, making it a significant public health concern. Infections caused by Acinetobacter can be difficult to treat and may require the use of last-resort antibiotics.
Preventing the spread of Acinetobacter in healthcare settings is important and includes practices such as hand hygiene, environmental cleaning, and contact precautions for patients with known or suspected infection.
'Acinetobacter calcoaceticus' is a species of gram-negative, aerobic bacteria that is commonly found in the environment, such as in soil and water. It is a non-motile, oxidase-negative organism that can form biofilms and has the ability to survive in a wide range of temperatures and pH levels.
While 'Acinetobacter calcoaceticus' itself is generally considered to be a low-virulence bacterium, it is closely related to other species within the genus 'Acinetobacter' that are known to cause healthcare-associated infections, particularly in immunocompromised patients or those with underlying medical conditions. These infections can include pneumonia, bloodstream infections, meningitis, and wound infections.
It is important to note that the identification of 'Acinetobacter calcoaceticus' can be challenging due to its tendency to form mixed cultures with other 'Acinetobacter' species, as well as its ability to undergo genetic changes that can make it difficult to distinguish from other members of the genus. Accurate identification and antimicrobial susceptibility testing are critical for appropriate treatment and infection control measures.
An encyclopedia is a comprehensive reference work containing articles on various topics, usually arranged in alphabetical order. In the context of medicine, a medical encyclopedia is a collection of articles that provide information about a wide range of medical topics, including diseases and conditions, treatments, tests, procedures, and anatomy and physiology. Medical encyclopedias may be published in print or electronic formats and are often used as a starting point for researching medical topics. They can provide reliable and accurate information on medical subjects, making them useful resources for healthcare professionals, students, and patients alike. Some well-known examples of medical encyclopedias include the Merck Manual and the Stedman's Medical Dictionary.
Carbapenems are a class of broad-spectrum beta-lactam antibiotics, which are used to treat severe infections caused by bacteria that are resistant to other antibiotics. They have a similar chemical structure to penicillins and cephalosporins but are more resistant to the enzymes produced by bacteria that can inactivate these other antibiotics. Carbapenems are often reserved for use in serious infections caused by multidrug-resistant organisms, and they are typically given intravenously in a hospital setting. Examples of carbapenems include imipenem, meropenem, doripenem, and ertapenem.