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)

We cloned into the structural fimbrial subunit gene from a fimbriated Haemophilus influenzae b a 1.5-kb kanamycin resistance gene. The resultant strain (RKAW5) was tested by Southern analysis, hemagglutination, and electron-micrographic examination to confirm gene inactivation. In comparison with the parent, RKAW5 exhibited a significant decrease in adherence to human buccal epithelial cells and in nasal colonization of yearling rhesus monkeys.
Infect Immun 1991 Dec
PMID:Inability to express fimbriae results in impaired ability of Haemophilus influenzae b to colonize the nasopharynx. 168 68

Contour-clamped homogeneous electric field pulsed-field gel electrophoresis (PFGE) was used in combination with Southern hybridization to construct a genomic restriction map for the pathogen Haemophilus influenzae serotype b, strain Eagan. Sites for four restriction endonucleases, EagI, NaeI, RsrII and SmaI, were located on the 2100 kbp circular chromosome. Twelve potential virulence loci have been placed on the map together with certain loci essential for growth of the bacteria (e.g. ribosomal RNA operons). PFGE also provided a valuable tool for characterizing ten capsulated, type b isolates (other than Eagan) known to be genetically heterogeneous and two laboratory-derived variants (transformants) derived through complex recombinational events involving random uptake of high-molecular-mass donor genomic DNA.
J Gen Microbiol 1990 Dec
PMID:A physical map of the genome of Haemophilus influenzae type b. 170 60

Monoclonal antibodies raised against Haemophilus influenzae and Neisseria gonorrhoeae were used to investigate similarities or differences in the lipopolysaccharide antigens of pathogenic and commensal strains of several Gram-negative bacteria indigenous to mucosal surfaces of humans. In immunoblotting experiments, 20 of 36 monoclonal antibodies showed cross-reactions between species of Neisseria and Haemophilus. The common epitopes were present on N. gonorrhoeae, N. meningitidis, N. lactamica, H. influenzae including biogroup aegyptius, and occasionally H. parainfluenzae. No other commensal Neisseria or Gram-negative organisms tested reacted with the monoclonal antibodies with one exception; a single strain of pathogenic Escherichia coli was recognised by a N. gonorrhoeae-specific monoclonal antibody. One monoclonal antibody, raised against N. gonorrhoeae lipopolysaccharide, reacted with N. gonorrhoeae (32 of 59 strains), N. meningitidis (9 of 26 strains), H. influenzae (6 of 16 strains). An epitope expressed by H. influenzae and implicated in its virulence was also present on 14 of 59 strains of N. gonorrhoeae and was shown to comprise a digalactoside structure, alpha-galactosyl-1,4-beta-galactose (Gal alpha 1,4Gal beta), also found on human cells.
Microb Pathog 1990 Dec
PMID:Antigenic similarities in lipopolysaccharides of Haemophilus and Neisseria and expression of a digalactoside structure also present on human cells. 171 Nov 42

The chain length of oligosaccharides required for antibody binding has been studied by using the capsular polysaccharide from Haemophilus influenzae type b or oligosaccharides derived from it. The concentration of competing antigens required to achieve a 50% inhibition of antibody binding by human polyclonal antisera in an in vitro competition enzyme-linked immunosorbent assay decreased progressively from greater than 10(-3) to 5 x 10(-7) M as the inhibiting saccharide chain length increased from 1 to 262 repeat units. Even small oligosaccharides (one or two repeat units) are potentially capable of competing to a significant level if a high enough concentration of saccharides is used. A similar pattern of reactivity was seen with a monoclonal anti-polyribosyl ribitol phosphate antibody, suggesting that the differences in the avidity of the antibody subpopulations in the polyclonal antisera do not contribute to the binding patterns observed. The binding reaction was specific as evaluated with pneumococcal saccharides. Furthermore, an oligosaccharide-protein conjugate binds antibody better than the free oligosaccharides do. Such a difference in binding was not observed between the polysaccharide and a polysaccharide-protein conjugate. Overall, the data suggest that identical epitopes are expressed by oligomeric and polymeric forms of the antigen and that a particularly more stable conformation in polysaccharides is preferred by antibodies. Covalent coupling of oligomers to protein increases the expression of stable conformation of epitopes. The data further suggest that this kind of antigenic analysis may be important for the design and synthesis of glycoconjugate vaccines.
Infect Immun 1991 Dec
PMID:Distinct pattern of antibody reactivity with oligomeric or polymeric forms of the capsular polysaccharide of Haemophilus influenzae type b. 171 75

We investigated whether production of histamine by bacteria isolated from sputum of patients with infective lung diseases could be attributed to the presence of histidine decarboxylase (HD). Twenty gram-positive and 20 gram-negative organisms were studied for their ability to decarboxylate 14C-histidine in vitro over the pH range 4.5-7.5. Of the bacteria investigated, lysates from the gram-negative species Haemophilus influenzae, H. parainfluenzae, Moraxella (Branhamella) catarrhalis and Pseudomonas aeruginosa liberated 14CO2 and histamine from 14C-histidine in the presence of the cofactor pyridoxal phosphate. In contrast, results obtained in the absence of cofactor were similar to those of negative (lysate-free) controls suggesting that the HD enzymes of these species resembled those previously described in other gram-negative bacteria. No HD activity was detected over this pH range in lysates from gram-positive species. This finding correlated with earlier observations that these gram-positive organisms did not produce histamine in vitro.
J Med Microbiol 1991 Dec
PMID:Histidine decarboxylases from bacteria that colonise the human respiratory tract. 172 55

Human antibodies specific for the Haemophilus influenzae b polysaccharide (Hib PS) frequently express a cross-reactive idiotype (CRI), and commonly utilize a VL region that is the product of the V kappa II gene A2. To examine further anti-Hib PS V region expression and to determine whether CRI expression is correlated with the V kappa IIA2 chain, we isolated a monoclonal antibody (MAb) reactive with an idiotypic determinant of anti-Hib PS antibodies. This MAb inhibited Hib PS binding but did not react with Ig isotypic determinants. The CRI recognized by this MAb, designated HibId-1, was associated with the Hib PS-combining site since the reactivity of the MAb with anti-Hib PS antibodies could be inhibited by Hib PS. HibId-1 was expressed by 17 of 17 clonally purified and sequence-defined anti-Hib PS antibodies having V kappa IIA2 L chains. In contrast, 0 of 10 anti-Hib PS antibodies having either V lambda, V kappa I, or V kappa III chains expressed HibId-1. Western blot analysis showed that the MAb anti-CRI reacted with isolated anti-Hib PS V kappa IIA2 L chains but not with H chains or other L chains, indicating that the HibId-1 determinant is localized to the V kappa IIA2 chain, and does not require pairing with H chain for expression. Anti-Hib PS antibodies bearing HibId-1 were present in at least 85% of subjects immunized with either free Hib PS or Hib PS coupled to diphtheria toxoid (Hib PS-DT), and comprised on the average 60% of the total vaccine-induced serum anti-Hib PS. HibId-1 expression was not related to age at vaccination inasmuch as infants, children, and adults had similar distributions of HibId-1-positive anti-Hib PS after vaccination with Hib PS-DT. HibId-1 was expressed at a lower frequency and comprised a smaller fraction of the total anti-Hib PS antibody in adult preimmunization sera as compared to post-Hib PS immunization sera, suggesting that immunization preferentially stimulates HibId-1-positive B cells. These data demonstrate that antibodies bearing HibId-1/V kappa IIA2 comprise a predominant component of the anti-Hib PS response induced by immunization, and that this pattern of VL expression is established early in ontogeny.
J Clin Invest 1991 Dec
PMID:An idiotypic marker associated with a germ-line encoded kappa light chain variable region that predominates the vaccine-induced human antibody response to the Haemophilus influenzae b polysaccharide. 175 43

In this paper an in vitro culture system for the induction of an antibody response to the Haemophilus influenzae type b polysaccharide (PRP) is described. Anti-PRP IgM and IgG antibody-secreting cells (ASC) and anti-diphtheria toxoid (DT) IgG ASC were detected in cultures of blood B and T cells derived from donors 4 to 6 wk after immunization with Haemophilus influenzae type b oligosaccharide-mutant diphtheria toxin (CRM197) conjugate (HbOC) and required in vitro restimulation with HbOC. When lymphocytes from HbOC-vaccinated donors were stimulated with PRP, anti-PRP IgM and IgG ASC could be detected in 50% offGe cases. Lymphocytes from PRP-vaccinated donors or non-vaccinated donors consistently failed to generate anti-PRP antibodies after in vitro stimulation with HbOC. Optimal in vitro responses were observed at concentrations of 0.06 to 0.6 micrograms/ml of Ag. At higher doses of Ag (6 micrograms/ml) anti-PRP and anti-DT antibody responses were suppressed. The in vitro generation of anti-PRP and anti-DT ASC, as detected by a spot-forming cell assay was shown to be T cell dependent, Ag dependent, and Ag specific. This culture system provides a model for the study of human B cell activation and immunoregulation by polysaccharide-protein conjugates and polysaccharides.
J Immunol 1991 Dec 15
PMID:In vitro induction of a Haemophilus influenzae type b polysaccharide-specific antibody response in human peripheral blood lymphocytes of individuals recently vaccinated with an oligosaccharide-protein conjugate. 175 96

This report emphasizes new clinical information about bacterial meningitis in infants and children. Important elements of diagnosis include examination for the presence of shock and increased intracranial pressure. In such cases, initial treatment should focus on appropriate fluid therapy, administration of oxygen, reduction of intracranial pressure and use of corticosteroids. Currently, antibiotics of choice include ampicillin plus either cefotaxime or ceftriaxone in young infants, and one of these cephalosporins in older patients (beyond 3 months of age). Shorter durations of therapy (5 to 7 days for meningococcus, 7 days for haemophilus and 7-10 days for pneumococcus) are now commonly employed. In many centers, dexamethasone is started before the first dose of antibiotic and continued for 4 days to reduce neurologic and audiologic sequelae. Future trends will include studies of endotoxin neutralizers and non-steroidal anti-inflammatory drugs to reduce further tissue injury in meningitis. Prevention of meningitis is the ultimate goal. Since Haemophilus influenzae vaccination can now begin at 2 months, this approach may bring important results soon.
Clin Pediatr (Phila) 1991 Dec
PMID:Bacterial meningitis--an update. 176 75

It was the aim of this study to examine the influence of bacterial or viral infections of the airways on the ciliary beat rate in childhood. In 21 children with bacterial bronchopulmonary infections a mean ciliary beat rate of 9.1 +/- 2.4. Hz was found that did not differ significantly from that of the group of the healthy subjects (9.9 +/- 1 Hz). In 7 of the 21 patients we could identify an infection of the respiratory tract with Haemophilus influenzae; in those children there was a marked reduction of the mean ciliary beat rate at 8 Hz. 13 children with viral bronchopulmonary infections had a mean ciliary beat rate of 11.8 +/- 1.8 Hz, which is significantly enhanced when compared with that of the healthy group. Compared with the mean ciliary beat rate of bacterial infections of the respiratory tract there is a significant difference. In viral infections of the airways no value below 9 Hz was found. In case of markedly reduced ciliary beat rate a bacterial infection must be assumed.
Pneumologie 1991 Dec
PMID:[Ciliary function in bronchopulmonary infections in childhood]. 176 52

Effective treatment of acute bacterial exacerbations of chronic bronchitis (ABE) reduces the number of such exacerbations in such patients and may decrease or eliminate background symptoms and improve pulmonary function. The pathologic and physiologic abnormalities of the bronchial system in chronic bronchitis that predispose to bacterial infection probably include impaired mucociliary clearance, obstructed bronchioles, and bacterial infections of the bronchial epithelium. Exacerbations of bronchopulmonary symptoms are usually observed with ABE, although these symptoms are not unique to ABE. While culture and sensitivity testing is not usually required, microscopic examination of sputum is critical to determine the presence of bacterial infection. Bacteria in numbers significantly above the levels present when the patient's condition is stable and at least a doubling of the sputum neutrophil inflammatory level are essential criteria. Bacterial species observed with ABE include Haemophilus influenzae, Haemophilus parainfluenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Neisseria species, with a lesser incidence of Klebsiella and Pseudomonas species. One or more elements of background therapy for ABE should accompany antimicrobial therapy, for example, physiotherapy, bronchodilators, and so forth. Ampicillin is effective, safe, economical, and thus remains the drug of choice for ABE. Quinolones are an effective alternative when ampicillin cannot be tolerated or if organisms are resistant. Dosing is at the upper range of recommendations, and the chosen drug should be given for a 10-14-day regimen. Patients should be reevaluated if symptoms and physical findings do not return to baseline after 5-7 days.
Am J Med 1991 Dec 30
PMID:Treatment of acute exacerbations of chronic bronchitis: state of the art. 176 8


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