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)

During initiation of the association between the squid host Euprymna scolopes and its bacterial partner Vibrio fischeri, the bacteria induce dramatic morphogenesis of the host symbiotic organ, a portion of which involves the signaling of widespread apoptosis of the cells in a superficial ciliated epithelium on the colonized organ. In this study, we investigated the role in this process of lipopolysaccharide (LPS), a bacterial cell-surface molecule implicated in the induction of animal cell apoptosis in other systems. Purified V. fischeri LPS, as well as the LPS of V. cholerae, Haemophilus influenzae, Escherichia coli, and Shigella flexneri, added in the concentration range of pg/ml to ng/ml, induced apoptosis in epithelial cells 10- to 100-fold above background levels. The absence of species specificity suggested that the conserved lipid A portion of the LPS was the responsible component of the LPS molecule. Lipid A from V. fischeri, E. coli, or S. flexneri induced apoptosis. In addition, strains of H. influenzae carrying a mutation in the htrB gene, which is involved in the synthesis of virulent lipid A, showed a diminished ability to induce apoptosis of host cells. Confocal microscopy using fluorescently labeled LPS indicated that the LPS behaves similar to intact bacterial symbionts, interacting with host cells in the internal crypt spaces and not directly with the superficial epithelium. Although LPS was able to induce apoptosis, it did not induce the full morphogenesis of the ciliated surface, suggesting that multiple signals are necessary to mediate the development of this animal-bacterial mutualism.
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PMID:Vibrio fischeri lipopolysaccharide induces developmental apoptosis, but not complete morphogenesis, of the Euprymna scolopes symbiotic light organ. 1102 84

We have generated a hybridoma cell line which produces an 8C7Br1 clone of the IgM antibody isotype. It recognizes the 50-, 65-, and 60-kDa antigens and is reactive with strains of N. meningitidis in the 98% of local Neisseria genera by Dot-ELISA assays. Two percent of the strains of N. meningitidis B do not present reactivity with the 8C7Br1 monoclonal antibody (MAb). The antibody reacted against N. meningitidis of serogroups A, B, C, X, Y, Z, and different serotypes and subtypes of N. meningitidis B and C by means of Dot-ELISA and Immunoblot. It cross-reacted with Neisseria gonorrhoeae, Neisseria lactamica, Haemophilus influenzae type b, Escherichia coli, Salmonella typhimurium, Salmonella typhi, Shigella flexneri, Bordetella pertussis, and Bacillus subtilis. The 8C7Br1 MAb reacted with the 65-kDa protein present in the prototype meningococcal strains B:16:B6(B2a:P1.5.2) and 2996 (B2b:P1.5.2). In H. influenzae type b, E. coli and B. subtilis, the MAb recognized the protein of 60, 65, and 70 kDa, respectively. FACS analysis showed that 8C7Brl MAb could recognize the 50-kDa protein on the surface of N. meningitidis homologous (B:4:P1.9) strain. These results, together with the bactericidal activity of 8C7Br1, and an experiment of passive protection in mice, demonstrated the potential importance of the cross-reactive protein as a candidate antigen for N. meningitidis B vaccine composition.
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PMID:Production and characterization of a new monoclonal antibody against Neisseria meningitidis: study of the cross-reactivity with different bacterial genera. 1115 96

Shigella genes expressed during infection likely contribute to adaptation and virulence in the host. Using differential display PCR (DDPCR), a cDNA fragment from Shigella flexneri serotype 5 that showed enhanced expression in a murine model was identified, cloned and sequenced. Enhanced expression was verified by RNA dot blot. The full-length gene was cloned using PCR and sequenced. The complete gene sequence was BLAST searched against GenBank, and exhibited strong homology to genes encoding Haemophilus influenzae D15 and Pasteurella multocida Oma87 protective outer membrane antigens. The S. flexneri gene putatively encodes a approximately 90-kDa protein and was termed oma90. The deduced amino acid sequence from oma90 was analyzed and compared to the D15/Oma87 antigens. Additionally, oma90 mapped to a cluster of orthologous groups, and probably contains an ancient conserved domain. The chromosomal organization of oma90 was similar to that for H. influenzae and P. multocida as well as for other known homologues. Northern blot revealed that the oma90 transcript encoded only oma90. This report represents the first description of a S. flexneri gene identified based on enhanced expression in the host. Furthermore, we report the first evidence demonstrating in vivo regulation of a member of the d15/oma87 gene family.
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PMID:Identification and characterization of an in vivo regulated D15/Oma87 homologue in Shigella flexneri using differential display polymerase chain reaction. 1117 81

Bacteriophage SfV is a temperate serotype-converting phage of Shigella flexneri. SfV encodes the factors involved in type V O-antigen modification, and the serotype conversion and integration-excision modules of the phage have been isolated and characterized. We now report on the complete sequence of the SfV genome (37,074 bp). A total of 53 open reading frames were predicted from the nucleotide sequence, and analysis of the corresponding proteins was used to construct a functional map. The general organization of the genes in the SfV genome is similar to that of bacteriophage lambda, and numerous features of the sequence are described. The superinfection immunity system of SfV includes a lambda-like repression system and a P4-like transcription termination mechanism. Sequence analysis also suggests that SfV encodes multiple DNA methylases, and experiments confirmed that orf-41 encodes a Dam methylase. Studies conducted to determine if the phage-encoded methylase confers host DNA methylation showed that the two S. flexneri strains analyzed encode their own Dam methylase. Restriction mapping and sequence analysis revealed that the phage genome has cos sites at the termini. The tail assembly and structural genes of SfV show homology to those of phage Mu and Mu-like prophages in the genome of Escherichia coli O157:H7 and Haemophilus influenzae. Significant homology (30% of the genome in total) between sections of the early, regulatory, and structural regions of the SfV genome and the e14 and KpLE1 prophages in the E. coli K-12 genome were noted, suggesting that these three phages have common evolutionary origins.
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PMID:Complete genomic sequence of SfV, a serotype-converting temperate bacteriophage of Shigella flexneri. 1188 6

Vibrio cholerae uses a variety of strategies for obtaining iron in its diverse environments. In this study we report the identification of a novel iron utilization protein in V. cholerae, VciB. The vciB gene and its linked gene, vciA, were isolated in a screen for V. cholerae genes that permitted growth of an Escherichia coli siderophore mutant in low-iron medium. The vciAB operon encodes a predicted TonB-dependent outer membrane receptor, VciA, and a putative inner membrane protein, VciB. VciB, but not VciA, was required for growth stimulation of E. coli and Shigella flexneri strains in low-iron medium. Consistent with these findings, TonB was not needed for VciB-mediated growth. No growth enhancement was seen when vciB was expressed in an E. coli or S. flexneri strain defective for the ferrous iron transporter Feo. Supplying the E. coli feo mutant with a plasmid encoding either E. coli or V. cholerae Feo, or the S. flexneri ferrous iron transport system Sit, restored VciB-mediated growth; however, no stimulation was seen when either of the ferric uptake systems V. cholerae Fbp and Haemophilus influenzae Hit was expressed. These data indicate that VciB functions by promoting iron uptake via a ferrous, but not ferric, iron transport system. VciB-dependent iron accumulation via Feo was demonstrated directly in iron transport assays using radiolabeled iron. A V. cholerae vciB mutant did not exhibit any growth defects in either in vitro or in vivo assays, possibly due to the presence of other systems with overlapping functions in this pathogen.
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PMID:Vibrio cholerae VciB promotes iron uptake via ferrous iron transporters. 1858 40

Thomas Willis (1621-1675) described patients with, "inflammation of the meninges with a continual fever" as well as an early (1661) epidemic of meningitis. Robert Whytt (1714-1766) provided a classic depiction of tuberculous meningitis and its stages, later extended by John Cheyne (1777-1836). Gaspard Vieusseux (1746-1814) and Andre Matthey (1778-1842) in Geneva, and Elisa North (1771-1843) in Massachusetts, described epidemic (meningococcal) meningitis. Heinrich Quincke (1842-1922) utilized his new technique of lumbar puncture (1891) to provide an early analysis of cerebrospinal fluid (CSF). William Mestrezat (1883-1929), and H. Houston Merritt (1902-1979) later compiled large series of CSF profiles in meningitis. Organisms causing meningitis were identified in the late 19th century including Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae. Vladimir Kernig (1840-1917) and Josef Brudzinski (1874-1917) described their eponymous signs in 1882 and 1909. Successful treatment of meningitis began with the introduction of serum therapy for meningococcal meningitis by Georg Joachmann (1874-1915) in Germany and Simon Flexner (1863-1946) in America. Antibiotic therapy began in the 20th century with the use of sulfonamides by Francois Schwentker (1904-1954) and penicillin by Chester Keefer (1897-1972). Vaccination against meningitis debuted in the early 20th century, and progressed to the development of vaccines against Neisseria meningitidis and Haemophilus influenzae, which remain mainstays of modern medicine.
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PMID:Chapter 28: a history of bacterial meningitis. 1989 31

Background: In 2002, the World Health Organization (WHO) launched a regional microbiology external quality assessment (EQA) programme for national public health laboratories in the African region, initially targeting priority epidemic-prone bacterial diseases, and later including other common bacterial pathogens. Objectives: The aim of this study was to analyse the efficacy of an EQA programme as a laboratory quality system evaluation tool. Methods: We analysed the proficiency of laboratories' performance of bacterial identification and antimicrobial susceptibility testing (AST) for the period 2011-2016. The National Institute for Communicable Diseases of South Africa provided technical coordination following an agreement with WHO, and supplied EQA samples of selected bacterial organisms for microscopy (Gram stain), identification, and antimicrobial susceptibility testing (AST). National public health laboratories, as well as laboratories involved in the Invasive Bacterial Diseases Surveillance Network, were enrolled by the WHO Regional Office for Africa to participate in the EQA programme. We analysed participants' results of 41 surveys, which included the following organisms sent as challenges: Streptococcus pneumonia, Haemophilus influenzae, Neisseria meningitidis, Salmonella Typhi, Salmonella Enteritidis, Shigella flexneri, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus anginosus, Enterococcus faecium, Serratia marcescens, Acinetobacter baumannii, and Enterobacter cloacae. Results: Eighty-one laboratories from 45 countries participated. Overall, 76% of participants obtained acceptable scores for identification, but a substantial proportion of AST scores were not in the acceptable range. Of 663 assessed AST responses, only 42% had acceptable scores. Conclusion: In the African Region, implementation of diagnostic stewardship in clinical bacteriology is generally suboptimal. This report illustrates that AST is poorly done compared to microscopy and identification. It is critically important to make the case for implementation of quality assurance in AST, as it is the cornerstone of antimicrobial resistance surveillance reporting and implementation of the Global Antimicrobial Resistance Surveillance System.
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PMID:External Quality Assessment of Bacterial Identification and Antimicrobial Susceptibility Testing in African National Public Health Laboratories, 2011-2016. 3184 47

Since ancient times complementary therapies have been based on the use of medicinal plants, natural preparations and essential oils in the treatment of various diseases. Their use in medical practice is recommended in view of their low toxicity, pharmacological properties and economic impact. This paper aims to test the antimicrobial effect of natural preparation based on clove, orange and bergamot essential oils on a wide range of microorganisms that cause infections in humans including: Streptococcus pyogenes, Staphylococcus aureus, Shigella flexneri, Candida parapsilosis, Candida albicans, Pseudomonas aeruginosa, Escherichia coli, Salmonella typhimurium and Haemophilus influenza. Three natural preparations such as one-component emulsions: clove (ECEO), bergamote (EBEO), and orange (EOEO), three binary: E(BEO/CEO), E(BEO/OEO), E(CEO/OEO) and a tertiary emulsion E(OEO/BEO/CEO) were obtained, characterized and tested for antimicrobial effects. Also, the synergistic/antagonistic effects, generated by the presence of the main chemical compounds, were studied in order to recommend a preparation with optimal antimicrobial activity. The obtained results underline the fact that the monocomponent emulsion ECEO shows antimicrobial activity, while EOEO and EBEO do not inhibit the development of the analyzed strains. In binary or tertiary emulsions E(BEO/CEO), E(CEO/OEO) and E(OEO/ BEO/CEO) the antimicrobial effect of clove oil is potentiated due to the synergism exerted by the chemical compounds of essential oils.
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PMID:Natural Preparations Based on Orange, Bergamot and Clove Essential Oils and Their Chemical Compounds as Antimicrobial Agents. 3325 27


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