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

While Actinobacillus actinomycetemcomitans has been associated with rapidly progressive periodontal destruction in man, the closely related Haemophilus aphrophilus has not been related to periodontal disease. This may be due to differences in composition and structure of the lipopolysaccharides (LPS) of these dental-plaque bacteria, since LPS probably exerts a series of detrimental effects on the periodontium. LPS was prepared by the phenol-water procedure from the type strains of A. actinomycetemcomitans and H. aphrophilus, purified by hexane extraction and ultracentrifugation, and analyzed with gas chromatography and gas chromatography-mass spectrometry. While the lipid content of LPS from A. actinomycetemcomitans constituted 35.4%, it was only 18.4% in H. aphrophilus: 3-hydroxytetradecanoic and tetradecanoic acids were 21.1 and 14.3% in A. actinomycetemcomitans and 10.9 and 7.5% in H. aphrophilus. There were qualitative and quantitative differences in the polysaccharide portions of their LPS. A actinomycetemcomitans contained both D-glycero-D-mannoheptose and L-glycero-D-mannoheptose (7.8 and 11.3%); H. aphrophilus contained only L-glycero-D-mannoheptose (17.4%). The rhamnose, fucose, galactose, glucose, and glucosamine/galactosamine contents in A. actinomycetemcomitans were 2.6, 5.2, 10.1, 22.4, and 5.2%, respectively; in H. aphrophilus, they were 2.1, 2.6, 19.4, 36.4, and 3.7%. Chemical differences in LPS from A. actinomycetemcomitans and H. aphrophilus may contribute to the divergence in periodontopathogenic potential of these organisms and help taxonomic differentiation.
 ...
PMID:Chemical differences in lipopolysaccharides from Actinobacillus (Haemophilus) actinomycetemcomitans and Haemophilus aphrophilus: clues to differences in periodontopathogenic potential and taxonomic distinction. 277 74

Fluoranthene, a non-carcinogenic polycyclic aromatic hydrocarbon, inactivates Escherichia coli cells in the presence of near-ultraviolet light (NUV; 300-400 nm). E coli cells carrying defects in the uvrA6 or katF genes are sensitized to inactivation by the simultaneous treatment with fluoranthene and NUV, suggesting that DNA is a target and that hydrogen peroxide is generated. Haemophilus influenzae transforming DNA can be inactivated by the simultaneous treatment with fluoranthene and NUV confirming DNA as a target. Using the photooxidation of imidazole and histidine as probes, fluoranthene was found to generate singlet oxygen in organic and aqueous media. In water, it participated in electron transfer reactions, reducing nitro blue tetrazolium as well as ferricytochrome C. This reduction took place both in the presence of air, where superoxide anion was formed, and under argon. Simultaneous treatment with fluoranthene and NUV was incapable of inducing histidine-independent mutations. Simultaneous treatment with fluoranthene and NUV was incapable of inducing the uvrA gene product as evidenced by the absence of the induction of beta-galactosidase in an E coli operon fusion strain [uvrA215::Mud(Ap,lac)].
 ...
PMID:Phototoxic effects of fluoranthene, a polycyclic aromatic hydrocarbon, on bacterial species. 282 96

Three hundred and thirteen transtympanic aerators (TTA), including 309 T-tubes, were inserted between november 1985 and April 1987 at the Bretonneau hospital, Paris. Twenty-three (7%) were expelled spontaneously, 16 (5%) became obstructive and in 6 cases a change of TTA was required. The commonest complication was otorrhea. Younger children tended to develop early otorrhea. There were 7 cases (2%) of early otorrhea and 50 (16%) of secondary otorrhea. By contrast the onset of secondary otorrhea was independent of age. A relationship with penetration of water into the middle ear through the TTA could not be confirmed. At the present time the authors permit bathing without any special precautions. In parallel, between november 1985 and august 1987, 84 bacteriological samples were obtained in cases of otorrhea related with a TTA, whether or not the latter had been inserted at Bretonneau. Predominant organisms were Hemophilus influenzae (30%), Pseudomonas aeruginosa (30%) and Staphylococcus (18%). On the basis of results of antibiotic sensitivity studies using the organisms discovered in these samples, the authors suggest local therapy based upon polymyxin or rifamycin as treatment of first choice.
 ...
PMID:[Short-term complications of transtympanic aerators]. 284 50

A new gel filtration method was developed for purification of R-type lipopolysaccharides (lipooligosaccharides) from some nonenteric gram-negative bacteria, including Neisseria meningitidis, Haemophilus influenzae, and Bordetella pertussis. These wild-type lipooligosaccharides are poorly extractable by the phenol-chloroform-ether extraction method of C. Galanos, O. Luderitz, and O. Westphal [1969) Eur. J. Biochem. 9, 245-249) and therefore a new procedure was developed for their isolation. The lipooligosaccharides (LOS) were first extracted by hot phenol-water, treated with RNase, then disaggregated in deoxycholic acid, and purified by gel filtration on Sephadex G-75. By comparison the conventional hot phenol-water purification method using repeated ultracentrifugations yielded less LOS. The yield of LOS by gel filtration was 30 to 108% higher and the purity was better.
 ...
PMID:A method for purification of bacterial R-type lipopolysaccharides (lipooligosaccharides). 288 9

The major outer membrane protein (40 kDa) of the bacterium Haemophilus influenzae type b is a porin which forms transmembrane permeability channels. It has an exclusion limit for oligosaccharides of about 1.4 kDa. When this protein was added to the aqueous phase which was bathing a planar lipid bilayer, it caused the conductance of the membrane to increase by several orders of magnitude. At low protein concentrations (2-10 pM), the conductance of the membrane increased in a stepwise fashion with an average single-channel conductance of 1.1 nS in 1 M KCl. Single-channel experiments were performed with a variety of different salts. The conductance of single channels was proportional to the specific conductance of the aqueous solution which was bathing the membrane. Current through the pores was proportional to the applied voltage, indicating that these pores are not voltage-controlled. The 40 kDa porin was very slightly cation-selective: the pores were about 1.6-times more permeable to potassium ions than to chloride ions. These properties of the 40 kDa porin are those of large water-filled channels and are characteristic of most bacterial porins. The single-channel conductance of the porin is, however, much smaller than might be expected from its exclusion limit. A model is proposed which could explain the differences in apparent pore size.
 ...
PMID:Properties of the porin of Haemophilus influenzae type b in planar lipid bilayer membranes. 301 99

By phenol-water extraction an aqueous-phase soluble cellular lipopolysaccharide was isolated from Haemophilus pleuro-pneumoniae serotype 1. It was shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, hydrolysis, methylation, and both one- and two-dimensional 1H and 13C nuclear magnetic resonance studies to be an S-type lipopolysaccharide, which could be cleaved to yield a lipid A and an O-chain polysaccharide identified as a high molecular weight branched polymer of a tetrasaccharide repeating unit having the structure: (Formula: see text).
 ...
PMID:Structure of the O-chain of the lipopolysaccharide of Haemophilus pleuropneumoniae serotype 1. 303 18

Counterimmunoelectrophoresis, direct immunofluorescence and immunodiffusion procedures were used to serotype 15 strains of Haemophilus pleuropneumoniae isolated from the respiratory tract of pigs in southern Brazil. Antigens were prepared by extracting cultures with a saline solution or by the phenol-water method. Antisera were prepared in rabbits against serotypes 1, 2, 3 and 5. Thirteen of the isolates were type 5 and two were type 3. No differences were observed between the results obtained in serotyping with counter immunoelectrophoresis and direct immunodiffusion, but both procedures were significantly better than immunodiffusion except with the saline extracted antigen. Counterimmunoelectrophoresis was quicker, more sensitive and more easily performed than the other techniques.
 ...
PMID:Identification of serotypes of Haemophilus pleuropneumoniae by counterimmunoelectrophoresis. 308 19

A study was undertaken to evaluate hypertonic mannitol treatment in experimental lapin Haemophilus influenzae type b meningitis and to compare these results with those in normal rabbits. Increased intracranial pressure, brain water content, and concentrations of lactate and hypoxanthine in cerebrospinal fluid (CSF) were measured as a reflection of altered cerebral perfusion and hypoxia and potential brain injury associated with meningitis. A single dose of mannitol reduced transiently the CSF pressure of uninfected rabbits from 2.15 +/- 0.20 to 1.34 +/- 0.10 mm Hg (maximum reduction 34.9 +/- 8.4%; p less than 0.005). The time to the lowest pressure was 38.7 +/- 2.7 min after initiation of the infusion and the time to return of CSF pressure to initial values was 76.7 +/- 5.6 min. In infected mannitol-treated animals the CSF pressure was reduced from 4.78 +/- 0.53 to 2.61 +/- 0.55 mm Hg (maximum reduction 42.0 +/- 7.7%; p less than 0.005). Time to maximum pressure decrease was 44.0 +/- 5.6 min. CSF pressure returned to the initial level after 178.5 +/- 25.2 min. Four h after initiation of mannitol infusion the mean brain water content in infected mannitol-treated animals was 412 +/- 4 g H2O/100 g dry weight and in infected untreated animals it was 415 +/- 3 g H2O/100 g dry weight (p greater than 0.05). CSF lactate and hypoxanthine concentrations were significantly increased during the 20 h of meningeal inflammation (p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Mannitol treatment in experimental Haemophilus influenzae type b meningitis. 311 92

Lipopolysaccharide (LPS) was extracted from whole cells of Haemophilus actinomycetemcomitans Y4 by the hot phenol-water procedure. LPS was cleaved into its lipid A and polysaccharide moieties by hydrolysis in 1% acetic acid. The major component sugars of the polysaccharide were glucose, heptose, rhamnose, galactose, and fucose. LPS and lipid A from H. actinomycetemcomitans induced the release of interleukin-1 (IL-1) by LPS-responsive C3H/HeN murine peritoneal macrophages and cell line macrophages (P388D1 and J744.1), but not by LPS-nonresponsive C3H/HeJ peritoneal macrophages. The polysaccharide was unable to induce the release of IL-1. It suppressed the IL-1 release from LPS- and lipid A-stimulated macrophages, but not the production of cell-associated and intracellular IL-1. The addition of rhamnose, a sugar component of the polysaccharide, abrogated the inhibitory effect of the polysaccharide on IL-1 release. These results suggest the participation of a lectinlike molecule in IL-1 release.
 ...
PMID:Suppression of murine macrophage interleukin-1 release by the polysaccharide portion of Haemophilus actinomycetemcomitans lipopolysaccharide. 325 48

The phenol-phase soluble cellular lipopolysaccharide that was isolated by the phenol-water extraction from Haemophilus pleuropneumoniae serotype 2 was shown to be of the S type by sodium dodecyl sulfate--polyacrylamide gel electrophoresis, hydrolysis, methylation, specific degradations, and both one- and two-dimensional 1H and 13C nuclear magnetic resonance studies. It could be cleaved to yield a lipid A and an O-chain polysaccharide. This O-polysaccharide was identified as a high molecular weight unbranched linear polymer of a pentasaccharide repeating unit having the structure: (Formula: see text).
 ...
PMID:Structural studies of the O-chain of the phenol-phase soluble lipopolysaccharide from Haemophilus pleuropneumoniae serotype 2. 344 98


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>