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)

Chronic obstructive pulmonary disease (COPD) is equated with chronic bronchitis and emphysema as one disease entity. In COPD airflow limitation is relatively persistent--unlike asthma. Tests for "small-airways disease" form no part of routine practice, for their accuracy in detecting pathological change is debatable. The proteolytic theory of the pathogenesis of emphysema highlights the role of neutrophil elastase, antielastases, oxidants, antioxidants, and thus of potential new treatments. Clinical features of COPD include breathlessness, cough, and sputum, with airflow obstruction and lung hyperinflation. The differential diagnosis includes bronchiectasis, cystic fibrosis, and pulmonary hypertension, but pulmonary fibrosis, etc., is distinguished by radiological infiltrates. Plain chest radiography cannot reliably diagnose emphysema in life, but a new method measuring lung density from the computed tomographic (CT) scan allows location, quantitation, and diagnosis of emphysema (defined by enlargement of distal air spaces) in humans in life. "Pink puffers" with breathlessness, hyperinflation, mild hypoxemia, and a low PCO2 are contrasted with "blue bloaters" with hypoxemia, secondary polycythemia, CO2 retention, and pulmonary hypertension and cor pulmonale. Antismoking measures are a major aim in management. A bronchodilator regimen combining a slow-release oral theophylline with an inhaled beta 2-agonist, ipratropium, and high-dose inhaled steroids is proposed because even modest improvement in obstruction can help these patients. In acute exacerbations with purulent sputum, antimicrobials against Streptococcus pneumoniae and Hemophilus influenzae are used with controlled oxygen therapy aiming to keep the arterial PO2 over 50 mm Hg without the pH falling below 7.25. Influenza prophylaxis is recommended, but pneumococcal vaccination remains debatable. Chronic under-nutrition in "emphysema" implies controlled trials of feeding regimens--but these remain to be assessed. Long-term oxygen therapy is the only treatment known to prolong life in blue bloaters, and oxygen concentrators and transtracheal oxygen delivery are discussed. Pulmonary vasodilators (e.g., beta 2-agonists, hydralazine, nifedipine, angiotensin-converting enzyme [ACE] inhibitors, etc.) have not yet been proved to provide long-term reduction in pulmonary arterial pressure. Blue bloaters have severe nocturnal hypoxemia in rapid eye movement (REM) sleep that is corrected by oxygen or the investigational drug almitrine.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Chronic obstructive pulmonary disease. 304 40

Bactericidal effects of polyunsaturated fatty acids were investigated by using an in vitro killing assay. All gram-positive species tested were extremely susceptible to 10(-5) M arachidonic acid as were Neisseria, Branhamella, and Haemophilus spp. Pseudomonas aeruginosa and and members of the Enterobacteriaceae were resistant. The toxicity of polyunsaturated fatty acids for Staphylococcus aureus was dependent upon time, concentration, and fatty acid unsaturation. Arachidonic acid underwent peroxidation when incubated with S. aureus, but arachidonic acid peroxidation products had low bactericidal activity. Catalase protected S. aureus, whereas superoxide dismutase was ineffective. Scavengers of hydroxyl radicals or singlet oxygen or removal of halide ions had little effect on arachidonic acid-induced killing of bacteria, whereas transition metal chelators and some thiols were highly protective. S. aureus grown in iron-supplemented broth had increased iron content and arachidonic acid susceptibility. Ascorbate also potentiated arachidonic acid-induced killing of S. aureus. These observations indicate that bactericidal effects of polyunsaturated fatty acids are mediated by a peroxidative process involving H2O2 and bacterial iron.
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PMID:Bactericidal effects of polyunsaturated fatty acids. 308 65

Cytotoxic and hemolytic activity of Haemophilus (Actinobacillus) pleuropneumoniae serotype 1 strain CM5 was investigated because of the potential role as a virulence determinant. Viable bacteria were toxic for porcine and bovine neutrophils, whereas bacteria killed by heat treatment at 60 C for 1 hour were not. Similarly, bacteria-free culture supernatant was cytotoxic and hemolytic in assays that used porcine neutrophils and erythrocytes, whereas supernatant treated at 60 C for 1 hour had no activity. Erythrocytes from various species were susceptible to the hemolytic activity of bacteria-free culture supernatant, with ovine and bovine erythrocytes being most sensitive. The neutrophil-toxic and hemolytic activity of bacteria-free culture supernatant was inhibited by cholesterol and oxygen and abolished after trypsin digestion. The neutrophil-toxic and hemolytic activity was preserved during storage at or less than 4 C, but was lost rapidly at 56 C or 80 C. Neutralizing antibodies were demonstrated in serum of pigs and rabbits immunized with 10-fold concentrated culture supernatant of strain CM5 and in field pigs that had recovered from natural infection with H pleuropneumoniae serotype 1. Bacteria-free culture supernatants of 18 strains, including H pleuropneumoniae serotypes 1 through 10, Actinobacillus suis, and Haemophilus taxon minor group, were tested for heat-sensitive, neutrophil-toxic, and hemolytic activity. Fifteen strains were neutrophil toxic, but only 10 of these were hemolytic. Haemophilus pleuropneumoniae, serotype 1, strain VLS557; serotype 5, strain K17; and Haemophilus taxon minor group strain 33PN were neither cytotoxic nor hemolytic.
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PMID:Evaluation of heat-sensitive, neutrophil-toxic, and hemolytic activity of Haemophilus (Actinobacillus) pleuropneumoniae. 342 27

The ultrastructures and surface protein profiles of aerobically cultured Actinobacillus actinomycetemcomitans (Haemophilus actinomycetemcomitans) differed from those of cells cultured anaerobically. Similar ultrastructural differences were also observed when aerobic and anaerobic cultures of a strain of Escherichia coli were compared. These results suggest that oxygen-related variations in the bacterial cell surface may play a role in the adaptation of oral bacteria to different host environments.
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PMID:Effect of anaerobiosis on the surface ultrastructure and surface proteins of Actinobacillus actinomycetemcomitans (Haemophilus actinomycetemcomitans). 362 7

Actinobacillus actinomycetemcomitans and the genetically-related oral haemophili (Haemophilus segnis, Haemophilus aprhophilus and Haemophilus paraphrophilus) exhibit a range of sensitivities to the lethal effect of hydrogen peroxide (H2O2), A. actinomycetemcomitans being the most resistant. To extend this information, susceptibility to a range of H2O2 concentrations (10(-6)-10(-3) M) was assessed by incubating bacterial suspensions for 1 h at 37 degrees C in the presence of H2O2 and spreading the suspensions on chocolate agar plates to determine the concentration of H2O2 producing a 50 per cent reduction in colony-forming units (LD50). Catalase activity was quantified with a Clark-type oxygen electrode, which polarographically monitored the formation of dissolved oxygen in bacterial suspensions or sonicates following addition of reagent H2O2. Sensitivity to H2O2 did not correlate with catalase activity, either in intact cells or in bacterial sonicates. Specifically, some bacterial strains with undetectable catalase activity were highly resistant to H2O2. Micromolar concentrations of sodium azide which completely inhibited cell-associated catalase activity did not affect the resistance of A. actinomycetemcomitans to H2O2. Thus, the endogenous catalase activity of A. actinomycetemcomitans and certain oral haemophili is not an important determinant of resistance to the bactericidal effects of H2O2.
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PMID:Influence of endogenous catalase activity on the sensitivity of the oral bacterium Actinobacillus actinomycetemcomitans and the oral haemophili to the bactericidal properties of hydrogen peroxide. 386 73

Phagocytosis of Haemophilus somnus by bovine blood neutrophils required opsonization of the bacteria with antibodies against H. somnus. Few bacteria were phagocytosed in the absence of serum; in addition, absorption of immune serum with Formalin-killed H. somnus significantly reduced ingestion of H. somnus. Heat inactivation of antiserum (56 degrees C for 30 min) to eliminate complement activity had little effect on its ability to opsonize H. somnus for uptake by bovine neutrophils. Antiserum from an H. somnus-immunized calf and autologous sera from adult cattle supported equivalent phagocytosis of H. somnus by bovine neutrophils, suggesting that normal, healthy cattle may contain sufficient antibodies in their sera to facilitate phagocytosis of H. somnus. Although bovine neutrophils readily ingested H. somnus, they were unable to kill the bacterium in vitro. These same neutrophils readily killed opsonized Escherichia coli and Staphylococcus epidermidis, suggesting that H. somnus is able to survive and perhaps multiply within bovine neutrophils. Because bovine neutrophils stimulated with opsonized H. somnus demonstrated a reduced oxidative burst (as measured by chemiluminescence) compared with neutrophils stimulated by opsonized E. coli, we suggest that reduced production of reactive oxygen intermediates during the phagocytosis of H. somnus may account, in part, for the enhanced survival of H. somnus in bovine neutrophils.
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PMID:Bovine neutrophils ingest but do not kill Haemophilus somnus in vitro. 405 25

A Haemophilus aphrophilus pulmonary infection with abscess formation in a previously healthy 9-year-old girl is reported. This has not been reported earlier in the literature. The clinical features were extremely severe with respiratory, circulatory and renal insufficiency. Artificial ventilation for 10 days was necessary, initially with 100% oxygen and extremely high airway pressure. The girl is now in perfect health again.
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PMID:Severe pulmonary infection by Haemophilus aphrophilus in a non-compromised child. 405 72

Metabolic factors that suppress development of competence in Haemophilus influenzae during growth in the synthetic medium MI(c) have been identified. These include inosine, nicotinamide adenine dinucleotide, glycerol, and uracil. It is also possible to initiate competence in the presence of these substances if the oxygen tension in the culture is temporarily reduced.
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PMID:Identification of competence-repressing factors during log-phase growth of Haemophilus influenzae. 433 8

After a transition from high to low oxygen tension, there was a twofold to 50-fold increase in the content of membrane-bound respiratory pigments of Haemophilus parainfluenzae, and there were concurrent changes in the metabolism of the membrane phospholipids: (i) a twofold decrease in the rate of turnover of the phosphate in all the phospholipids; (ii) a shift from simple one-phase, linear incorporation of phosphate into phospholipids to a complex biphasic incorporation of phosphate into phospholipids; and (iii) an increase in the total phospholipids with a slight increase in the proportion of phosphatidylglycerol (PG) and a slight decrease in the proportion of phosphatidylethanolamine (PE). Changes in the rates of incorporation of phosphate into the phospholipids occurred without a change in the rate of bacterial growth. When the compensatory adjustment of the proportions of the respiratory pigments reached a steady state, the total phospholipid, the rate of incorporation of phosphate into phospholipids, and the proportion of PG fell. At steady-state proportions of cytochromes, the proportion of PE and the rate of turnover of the phosphate in the phospholipids increased. All through an incorporation experiment of 1.5 divisions, the specific activity of the phosphate of PG was twice that of phosphatidic acid (PA). The phosphate of PG turned over 1.2 to 1.5 times more rapidly than the phosphate of PA in cells with high and low cytochrome levels. If the PA was an accurate measure of the precursor for the cytidine-5'-diphosphate-diglyceride, which in turn was the precursor of all the lipids, then the results of these experiments suggested that exchange reactions, in addition to synthesis from PA, were involved in phospholipid metabolism. These reactions were more sensitive to changes in oxygen concentration than was the growth rate.
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PMID:Phospholipid metabolism during changes in the proportions of membrane-bound respiratory pigments in Haemophilus parainfluenzae. 576 29

Moxalactam, a novel beta-lactam antimicrobial agent in which oxygen has replaced sulfur in the six-membered ring of the conventional cephem nucleus, has in vitro activity against almost all commonly isolated bacterial pathogens including Staphylococcus aureus, the Enterobacteriaceae, Pseudomonas aeruginosa, Bacteroides fragilis, and Haemophilus influenzae. The clinical efficacy an toxicity of moxalactam alone was evaluated in the treatment of 100 infections, including 22 septicemias. Thirty-two infections involved P aeruginosa, while organisms resistant to one or more of the currently available cephalosporins or cefoxitin were isolated from cultures in 63 of the cases. The overall clinical response was favorable (infection cured or improved) in 86% of the infections. A child with Klebsiella pneumoniae ventriculitis and meningitis was cured with intravenous moxalactam alone. Six of 14 treatment failures involved P. aeruginosa, and P aeruginosa isolates resistant to moxalactam emerged during therapy of 12 infections. Side effects, usually mild diarrhea, occurred in only 8.8% of the patients. Except for some severe P aeruginosa infections outside the urinary tract, moxalactam is effective and safe single-agent therapy for infections caused by susceptible organisms and represents a major advancement in beta-lactam antimicrobial therapy.
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PMID:Moxalactam therapy for bacterial infections. 645 53


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