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)

The cerebral capillary endothelium is unique and functions as an effective blood-brain barrier (BBB) owing to its intercellular tight junctions and rare pinocytotic vesicles. To assess how bacterial meningitis alters the BBB, rats were inoculated intracisternally with three encapsulated meningeal pathogens (Escherichia coli K1+, Streptococcus pneumoniae type III, Haemophilus influenzae type b) and an unencapsulated mutant strain (H. influenzae Rd). After defined infection durations, the morphologic alterations of the cerebral capillary endothelium were quantitatively assessed by transmission electron microscopy. Results revealed a significant increase in pinocytotic vesicle formation (P less than 0.001) early after meningitis induction (4 h) that was sustained with longer infection durations (10 h, 18 h) for all encapsulated strains tested. In addition, there was a progressive increase in completely separated intercellular junctions with increasing infection duration, (P less than 0.05). 4 h after induction of meningitis with H. influenzae Rd, cerebrospinal fluid (CSF) bacterial concentrations, cerebral capillary morphologic changes, and functional BBB permeability to circulating 125I-albumin were similar to those observed with H. influenzae type b. However, prolonging the H. influenzae Rd infection to 18 h allowed for CSF clearance of the organism, thereby precluding the significant increase in separated junctions or progression of functional BBB permeability seen with the encapsulated H. influenzae type b. These data suggest a uniform morphologic explanation for altered BBB permeability in meningitis with a reproducible temporal sequence. Encapsulation does not appear essential for BBB injury, but may facilitate its progression by allowing the organism to evade host clearance.
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PMID:Morphologic alterations of the blood-brain barrier with experimental meningitis in the rat. Temporal sequence and role of encapsulation. 351 71

Three immunoglobulin preparations for intravenous infusion were compared in vivo to determine their relative protective capacity against several gram-negative and gram-positive pathogens. Polyglobin N is a conventional IgG concentrate. Psomaglobin N is identical in formulation to Polyglobin N but is prepared from the plasma of donors who have naturally high levels of antibody to lipopolysaccharide antigens of Pseudomonas aeruginosa. IgGMA is a conventional IgG concentrate containing 12% IgG and 16% IgA. In a murine model of burn wound sepsis the three IgG preparations were similarly protective against three or ten strains of P. aeruginosa. Psomaglobin N and Polyglobin N were significantly (p less than or equal to 0.015) more protective than IgG-MA against six of ten and three of ten strains of P. aeruginosa, respectively. In a murine model of Streptococcus pneumoniae type 3 pneumonia, the three Ig preparations were similarly protective. IgG-MA was significantly more protective (p less than or equal to 0.025) than Psomaglobin N and Polyglobin N against Salmonella typhimurium in murine peritonitis. However, the mean protective dose (PD50) of the two later preparations was less than or equal to 20 mg/kg body weight. In models of peritonitis both Psomaglobin N and Polyglobin N were more protective than IgGMA (p less than or equal to 0.004) against Haemophilus influenzae b, Klebsiella pneumoniae, Serratia marcescens 06:H3 and group B Streptococcus types 1b and 1c. Psomaglobin N and ciprofloxacin were employed to treat established polymicrobial murine burn wound sepsis resulting from contamination of the burn site with mixtures of P. aeruginosa and Staphylococcus aureus. Psomaglobin N or albumin was given once 16 h after challenge.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Prevention of gram-negative and gram-positive infections using 3 intravenous immunoglobulin preparations and therapy of experimental polymicrobial burn infection using intravenous Pseudomonas immunoglobulin G and ciprofloxacin in an animal model]. 357 Apr 85

Bronchial secretions obtained during bronchoscopic examination of 60 children suffering from respiratory tract infections were studied for the concentration of immunoglobulins, anti-proteolytic factors, lactoferrin, and lysozyme. Eleven children having bronchial asthma without a history of chronic or recurrent infections of the respiratory tract were designated as a control. The results were analysed in relation to clinical diagnosis (chronic bronchitis, bronchitis, bronchiectasis) or to the local status of bronchial mucosa at the time of bronchoscopy (no inflammation, inflammation, inflammation with documented bacterial infection). The statistical analysis of the results revealed a decrease of lactoferrin and locally produced IgA in the group of children suffering from bronchitis and chronic bronchitis. Samples infected with Haemophilus species had significantly higher concentration of lactoferrin than any other group. Similarly, albumin in this group was higher than in the other group except that other bacteria were present. Samples infected with Haemophilus also had increased concentrations of S-IgA, IgG, and anti-proteolytic factors when compared with the group without local inflammation.
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PMID:Studies of bronchial secretion. The influence of inflammatory response and bacterial infection. 396 91

We studied the adherence of Haemophilus influenzae to monkey respiratory mucosa using nasal turbinates maintained in organ culture. Adherence of capsulated and rough strains was not inhibited by monosaccharides, sucrose, human albumin, foetal calf serum or polyribophosphate. However, antisera directed against surface components decreased bacterial adherence. Although variation in adherence capacity in individual strains was observed there was no correlation with capsulation, anatomical site of strain isolation or biotype. Bacterial surface structures other than capsular material appear important in effecting upper respiratory tract colonization.
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PMID:Adherence of Haemophilus influenzae to monkey respiratory tissue in organ culture. 643 95

Research into the pathophysiology of bacterial meningitis has suggested a role for various endogenous inflammatory mediators, such as platelet-activating factor (PAF). In the present study, rats were inoculated intracisternally with various doses of PAF, with Haemophilus influenzae lipooligosaccharide (LOS) in high doses (20 ng) alone, and with a low dose of LOS (200 pg) with or without low doses of PAF (25 ng to 2.5 micrograms). Values for cerebrospinal fluid leukocytosis and percent blood-brain barrier permeability to systemically administered 125I-labeled albumin observed after inoculation of low-dose LOS with PAF were greater (P < 0.05) than those observed after inoculation of low-dose LOS alone and not statistically different from those observed after inoculation of high-dose LOS. PAF alone elicited an inflammatory response only at high doses (25 micrograms). These results support the hypothesis that low cerebrospinal fluid PAF concentrations, such as those observed in children with bacterial meningitis, may augment the inflammatory response to the presence of bacteria in the subarachnoid space.
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PMID:Platelet-activating factor augments meningeal inflammation elicited by Haemophilus influenzae lipooligosaccharide in an animal model of meningitis. 806 88

In an effort to develop a more effective therapy for postsplenectomy sepsis, ceftriaxone and human intravenous immunoglobulin (IVIG), alone and in combination, were evaluated for their efficacy against experimental Haemophilus influenzae type B (Hib) bacteremia in splenectomized and sham-operated infant rats. Five-day-old animals had either a splenectomy or sham operation. At 12 days of age, they were challenged intraperitoneally with Hib. Fifteen hours later blood specimens were obtained for quantitative bacterial cultures, and immediately thereafter therapy was started with ceftriaxone, IVIG, combination of ceftriaxone and IVIG, or albumin (control). Quantitative blood cultures were repeated 24 and 48 hours after the treatment. Prior to the treatments, splenectomized animals had significantly higher bacterial counts in blood when compared with sham-operated animals (P < .001). Splenectomized animals receiving IVIG, ceftriaxone, or the combination of IVIG and ceftriaxone had significantly increased bacterial clearance from blood when compared with the controls (P < .01). In addition, animals treated with ceftriaxone or the combination of IVIG and ceftriaxone had significantly increased bacterial clearance compared with the IVIG alone treatment group (P < .01). Overall, the mortality was significantly higher in splenectomized animals compared with the sham-operated animals (P < .05). The control animals had significantly higher mortality compared with the IVIG, ceftriaxone, and combined ceftriaxone and IVIG treatment groups (P < .05). There were no detrimental effects of combining IVIG and ceftriaxone together.
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PMID:Efficacy of passive immunotherapy in experimental postsplenectomy sepsis due to Haemophilus influenzae type B. 830 56

Sources of anti-Haemophilus somnus antibody in bovine uterine secretions following intramuscular immunization and subsequent intrauterine inoculation of killed H. somnus were investigated. Holstein cattle (n = 21) were immunized with a 270-kDa outer membrane protein from H. somnus (omp-270) by intramuscular injection. At estrus, the cattle were given an intrauterine inoculum of a heat-killed suspension of a homologous strain of H. somnus containing omp-270 (n = 7), a heterologous strain of H. somnus lacking omp-270 (n = 7), or phosphate-buffered saline (n = 7). Uterine secretions were sampled by saline lavage immediately prior to inoculation and at 6, 24, 48, 72, 96, and 120 h after inoculation. Immunoglobulin G subclass I (IgG1) and IgG2 antibody specific for omp-270 were detectable in estrous uterine secretions of all systemically immunized cattle from which an adequate sample was obtained. IgM antibody specific for omp-270 was detected in serum following immunization but was not consistently detected in the uterine secretions of any animal. IgA antibody specific for omp-270 was not detectable in either serum or uterine secretions following immunization or intrauterine inoculation. Ratios of antibody to immunoglobulin and ratios of immunoglobulin to albumin in serum and uterine secretions indicated that about half the IgG1 and essentially all the IgG2 in secretions originated in the serum. Relative titers of IgG1 and IgG2 omp-270-specific antibodies in the uterine lumen and serum gave no evidence for selective transport of either subclass from serum into local secretions. Neither heterologous nor homologous intrauterine inocula detectably altered the serum contribution to antibody in uterine secretions within the sampling period. On the basis of these results, development of a systemic IgG2 antibody response may provide the basis for local immunological protection in the bovine reproductive tract.
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PMID:Specific antibody to Haemophilus somnus in the bovine uterus following intramuscular immunization. 850 Aug 92

In an attempt to examine whether routes of bacterial entry into the central nervous system have any bearing on subsequent changes in blood-brain barrier permeability, we examined cerebrospinal fluid (CSF) penetration of circulating 125I-albumin in two different models of experimental meningitis due to K1 Escherichia coli, type III group B streptococcus, or Haemophilus influenzae type b in infant rats: hematogenous meningitis subsequent to subcutaneous inoculation of bacteria vs meningitis induced by direct inoculation of bacteria into the CSF via the cisterna magna. In the model of hematogenous meningitis, the mean CSF penetration was significantly greater in animals with H. influenzae type b meningitis than in those with meningitis due to K1 E. coli or type III group B streptococcus. In contrast, the mean CSF penetration was significantly enhanced in all animals with meningitis induced by intracisternal inoculation regardless of infecting pathogens. Tumor necrosis factor activity in CSF appeared to correlate with the functional penetration of circulating albumin across the blood-brain barrier in both models of experimental meningitis. These findings suggest that the alterations of blood-brain barrier permeability during development of experimental meningitis may vary for different models of inducing meningitis and that the mechanisms responsible for these different permeability changes may be multifactorial.
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PMID:Blood-brain barrier permeability during the development of experimental bacterial meningitis in the rat. 918 27

In the present study, we assessed the serum level of IL-6 and TNF-alpha by ELISA in patients with chronic lower respiratory tract infection. The serum levels of IL-6 and TNF-alpha of patients in acute exacerbation phase are higher than that of in stable phase. We also classified patients in acute exacerbation phase into two groups according to the microorganism of persistent infection. The serum level of IL-6 and TNF-alpha in the patients with persistent infection with Pseudomonas aeruginosa were higher than that with Haemophilus influenzae. Moreover, the serum level of IL-6 and TNF-alpha were found to be related with malnutrition which assessed by clinical indices such as the serum level of albumin and cholinesterase. The present result suggests that IL-6 and TNF-alpha may have relationship with not only inflammation in airway but also indices of nutrition in patients with chronic lower respiratory tract infection.
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PMID:[The evaluation of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) level in peripheral blood of patients with chronic lower respiratory tract infection]. 920 24

Unencapsulated Haemophilus influenzae is the second most common etiologic agent of otitis media in children. H. influenzae requires heme for aerobic growth in vitro and is able to utilize hemoglobin and complexes of heme-hemopexin, heme-albumin, and hemoglobin-haptoglobin and ferritransferrin as sources of iron and heme in vitro. Several of the acquisition mechanisms have been characterized and been shown to be heme repressible in vitro. However, little is known about the expression of heme and/or iron acquisition mechanisms during infections in the middle ear. This study was performed to determine if the genes encoding heme and iron acquisition proteins are transcribed during in vivo growth and to compare these findings with those for samples grown in vitro. Reverse transcriptase PCR (RT-PCR) was used to analyze total RNA fractions derived from in vitro- and in vivo-grown H. influenzae. Genes encoding the transferrin-binding proteins TbpA and TbpB, the 100-kDa hemopexin-binding protein HxuA, and the hemoglobin-binding protein HgpA were transcribed during otitis media. Twelve middle ear fluid samples were analyzed by blind RT-PCR to determine the transcriptional status of these genes in H. influenzae during otitis media. Five isolates had transcripts corresponding to tbpA, tbpB, and hxuA. The presence of hgpA transcripts was variable, depending on the presence of hgpA in the genome of the H. influenzae isolate. Samples without H. influenzae gene transcripts contained other etiologic agents commonly causing otitis media. These data demonstrate that H. influenzae iron and/or heme acquisition genes are transcribed during otitis media and suggest that the microenvironment during acute otitis media starves H. influenzae of heme.
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PMID:Transcription of genes encoding iron and heme acquisition proteins of Haemophilus influenzae during acute otitis media. 935 52


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