Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a retrospective morphological and microbiological study, 39 of 55 cases of bovine fibrinous pneumonia were diagnosed as fibrinous pleuropneumonia. Twenty-nine of these 39 (74%) were associated with Pasteurella hemolytica, but only two cases (5%) with P. multocida. In contrast, of the 16 cases classified as fibrinous bronchopneumonia, one (6%) was associated with P. hemolytica, and nine (56%) with P. multocida. In eight cases Mycoplasma and Hemophilus somnus were found in association with either P. hemolytica or P. multocida but were never isolated alone. We concluded that the use of the term pasteurellosis, implying Pasteurella as the cause, is imprecise because lesions associated with P. hemolytica fulfill the criteria of a fibrinous pleuropneumonia, whereas P. multocida is more likely to cause a bronchopneumonia with moderate amounts of fibrin.
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PMID:Correlation of microbiological and histological findings in bovine fibrinous pneumonia. 68 79

The leukotoxin of Pasteurella haemolytica has been implicated as one of the major virulence factors contributing to the pathogenesis of bovine pneumonic pasteurellosis. To gain a better understanding of the various biochemical, antigenic and toxigenic properties of the toxin, the genetic determinant (lkt) which encodes the leukotoxin has been cloned from P haemolytica serotype 1. Results from the molecular characterization of this determinant showed that four genes are required to synthesize and secrete the active toxin from P. haemolytica. This information provides the basis for genetic manipulation of the determinant to produce different "forms" of the leukotoxin for various studies. In addition, lkt was found to be homologous to the alpha-hemolysin determinant (hly) of Escherichia coli, Proteus vulgaris, P. mirabilis and Morganella morganii. Further evidence is being accumulated demonstrating the presence of the lkt/hly determinant in several species of Actinobacillus and Haemophilus. This suggests the wide dissemination of the lkt/hly determinant in many pathogenic bacteria and established the family of Rtx cytotoxins.
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PMID:Molecular characterization of cytotoxins produced by Haemophilus, Actinobacillus, Pasteurella. 219 1

According to the genetic relationships among Gram-negative bacilli the genus Pasteurella is included with the genus Haemophilus and the genus Acinobacillus within the family Pasteurellacae. Pasteurella multocida, the type species, is responsible for the majority of human Pasteurella infections. P. multocida is a member of the normal flora in the upper respiratory tract of many mammals or birds. It causes sporadic or epidemic diseases among different animal species, particularly pneumonia and atrophic rhinitis in swine in intensive breeding stations. The most common human infection with P. multocida is a local cellulitis following dog or cat bites and scratches. Serious local complications are sometimes responsible for prolonged disability. The respiratory tract is the second human source of P. multocida isolates. The frequency of recovery of P. multocida from oropharynx of apparently healthy pig breeders suggests that respiratory pasteurellosis could be an occupational disease. The mechanisms of virulence of P. multocida are unclear. Several factors are involved: capsules preventing phagocytosis, a dermonecrotic toxin causing experimental atrophic rhinitis, hyaluronidase, neuraminidase and proteases. Penicillin is considered to be the drug of choice for Pasteurella infection. Tetracyclin is efficient for bites but has no bactericidal effect. Oxacillin, first-generation cephalosporins, macrolides and aminoglycosides have poor activities. In the case of beta-lactamase producing strains a bactericidal effect could be achieved with fluoroquinolones or third generation cephalosporins.
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PMID:[Pasteurelloses]. 777 Mar 88

Seventeen complicated outbreaks of infectious coryza in layer, broiler-breeder, and broiler flocks were studied. In the layer flock outbreaks, drops in egg production of up to 35% were seen. In the broiler flocks and several of the layer flocks, losses due to persistent mortality and/or culling varied between 2 and 5%. Signs of infectious coryza in both layers and broiler-breeders were typical; in broilers, however, swollen head-like syndrome was seen. Except in one flock, no viral diseases were clinically or serologically detected. Excluding broiler-breeders, birds from most other flocks were serologically positive for Mycoplasma gallisepticum, and some were also positive for M. synoviae. Haemophilus paragallinarum was isolated from all of the outbreaks, but only as a pure culture in three outbreaks. Isolation of H. paragallinarum from sites such as liver, kidney, and particularly tarsal arthritis and ocular globes appears to be reported for the first time. Serovar A was isolated in eight outbreaks, serovar B in six, serovar C in one, and untypable serovars in two. The severity of these infectious coryza outbreaks may have been increased by concurrent salmonellosis, pasteurellosis, and mycoplasmosis, although under certain conditions H. paragallinarum is able to cause septicemia. Ten of the outbreaks occurred in birds vaccinated against infectious coryza; this may be due to the use of vaccines that do not provide protection against the types of H. paragallinarum that affect poultry in the region.
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PMID:Complicated infectious coryza outbreaks in Argentina. 783 27

A number of outer membrane proteins (OMPs), including a 30-kDa protein, may be important in eliciting immunity to Pasteurella haemolytica A1, the causative agent of bovine pneumonic pasteurellosis. To better understand the nature of the 30-kDa antigen, several genes encoding this protein were sequenced. Sequence analysis revealed that three separate genes encoding similar, yet distinct, versions of the 30-kDa protein are tandemly arranged on the P. haemolytica A1 chromosome. The genes appear to be transcribed from a single promoter. The deduced amino acid sequences of the proteins encoded by these genes are similar to a 28-kDa inner membrane lipoprotein of Escherichia coli and a 28-kDa membrane protein which may contribute to the virulence of Haemophilus influenzae type b strains.
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PMID:Analysis of tandem, multiple genes encoding 30-kDa membrane proteins in Pasteurella haemolytica A1. 833 49

As commercial producers of American bison (Bison bison) become more numerous, concerns relative to bison health management increase. Since loss due to respiratory disease associated with Pasteurella and related Pasteurellaceae is a major concern for cattle producers, a study was conducted to determine what types of Pasteurellaceae are carried by bison to evaluate the potential of pneumonic pasteurellosis in bison herds where management practices are comparable to those used for cattle. Tonsillar biopsies, collected in May (n = 29) and August (n = 25) 1997 from 24- to 30-month-old bison bulls, at the time of slaughter were cultured for Pasteurellaceae. Pasteurella spp. were isolated from all the samples collected in May. These included isolates identified as P. haemolytica, trehalosi, testudinis, and multocida subsp. multocida a and multocida b. Actinobacillus spp. and Haemophilus somnus were also isolated from some samples. Pasteurella spp., haemolytica, trehalosi, and multocida subsp. multocida a, multocida b and septica, plus 2 nonspeciated indole-positive biotypes, U2 and U16, were isolated from the second group of tonsil samples. Most of these organisms, including P. haemolytica, P. multocida subsp., and H. somnus are associated with disease in domestic livestock and should be regarded as potential pathogens for bison, particularly in animals which become stressed by management practices commonly used with cattle such as herding, crowding, and shipping.
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PMID:Pasteurellaceae isolated from tonsillar samples of commercially-reared American bison (Bison bison). 1048 Apr 56

The taxonomy of the family Pasteurellaceae Pohl 1981 appears to be as complex as that of Enterobacteriaceae. 16S rRNA sequencing indicates that the family should be divided into more than 20 genera. According to phylogenetic investigations, the genus Pasteurella sensu stricto includes three subclusters, two of which represent taxa mainly associated with avian hosts. True species of the genera Actinobacillus and Haemophilus have not been reported from birds. Several new taxa, which have been shown to belong to the family Pasteurellaceae Pohl 1981 have been reported from birds. Some of these seem to represent genus-like structures. Due to a high degree of host-specificity observed for many taxa belonging to the family, the existence of many more species can be foreseen as more avian species are examined. The pathogenesis of Pasteurella infections in birds is poorly understood. However, it has long been recognized that the severity of the disease and its incidence may vary considerably depending on several factors associated with the host, the environment or the bacterial strain. Several virulence factors of P. multocida, may be of importance for infection of birds and are discussed. There is some evidence that the capsule of P. multocida is of importance in the protection against phagocytosis by immunocompetent cells and that it mediates resistance to complement. Endotoxin is another factor which has persistently been associated with pathogenicity of P. multocida. There are some indications that the P. multocida exotoxin (PMT), which is involved in the pathogenesis of atrophic rhinitis in swine, may play a role in some avian infections. High molecular weight outer membrane proteins of P. multocida have been speculated to be the main iron acquisition system of avian strains of P. multocida and thereby representing virulence factors. An outer membrane protein with anti-phagocytic activity has also been demonstrated. The potential role of different enzymes in the pathogenesis P. multocida infections has been investigated, but not conclusively demonstrated. Apart from the knowledge concerning the PMT encoding gene toxA, very little is known about the genetic basis of diseases caused by pasteurellas associated with avian species.
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PMID:Avian pasteurellosis: Taxonomy of the organisms involved and aspects of pathogenesis. 1848 22