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 transport of Fe(III)-siderophore complexes and vitamin B12 across the outer membrane of Escherichia coli requires the TonB-dependent energy transduction system. A set of murine monoclonal antibodies (MAbs) was generated against an E. coli TrpC-TonB fusion protein to facilitate structure and function studies. In the present study, the epitopes recognized by these MAbs were mapped, and their distribution in gram-negative organisms was examined. Cross-species reactivity patterns obtained against TonB homologs of known sequence were used to refine epitope mapping, with some epitopes ultimately confirmed by inhibition experiments using synthetic polypeptides. Epitopes recognized by this set of MAbs were conserved in TonB homologs for 9 of 12 species in the family Enterobacteriaceae (including E. coli), including previously unidentified TonB homologs in Shigella, Citrobacter, Proteus, and Kluyvera species. These homologs were also detected by a polyclonal alpha-TrpC-TonB serum that additionally recognized the known Yersinia enterocolitica TonB homolog and a putative TonB homolog in Edwardsiella tarda. These antibody preparations failed to detect the known TonB homologs of either Pseudomonas putida or Haemophilus influenzae but did identify potential TonB homologs in several other nonenteric gram-negative species. In vivo chemical cross-linking experiments demonstrated that in addition to TonB, auxiliary components of the TonB-dependent energy transduction system are broadly conserved in members of the family Enterobacteriaceae, suggesting that the TonB system represents a common system for high-affinity active transport across the gram-negative outer membrane.
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PMID:Identification of TonB homologs in the family Enterobacteriaceae and evidence for conservation of TonB-dependent energy transduction complexes. 863 14

In this multicenter study conducted in eight European countries, 13,173 pathogens--all isolated from community-acquired infections in 1992 and 1993--were evaluated for their susceptibility to the following orally active antibiotics: penicillin G, ampicillin, amoxycillin plus clavulanic acid, cefaclor, cefuroxime, cefetamet, doxycycline and erythromycin. Ten centers in Italy, five in Germany, in the Netherlands and Switzerland, four in Greece and Spain, three in Hungary and one in Finland contributed to this study; ready-to-use standardized microtiter panels (Sceptor system, BBL, Heidelberg, Germany) were used throughout all assays. The most frequently encountered species were: Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae and non-typhoid Salmonella spp., Enterobacter cloacae, Streptococcus agalactiae, Haemophilus influenzae, Citrobacter freundii, Staphylococcus pyogenes, Streptococcus pneumoniae, Proteus vulgaris, Moraxella catarrhalis and Shigella spp. The percentage of susceptible isolates was assessed for each of the above-mentioned countries and European-wide with all the data available. For many species, the percentage of resistant isolates did not differ markedly between the countries considered. However, one of the most striking exceptions was the high prevalence of high-level penicillin-G-resistant S. pneumoniae isolates in Hungary and Spain; some of the low-level penicillin-G-resistant strains remained susceptible to cefuroxime, whereas complete cross-resistance occurred for all other beta-lactams studied. The high frequency of ampicillin-resistant H. influenzae isolates in Spain deserves mentioning; this could be attributed mainly to the prevalence of a beta-lactamase, as the addition of clavulanic acid rendered these strains susceptible to ampicillin. The penicillin compounds exhibited the greatest activity against Gram-positive pathogens, whereas cefetamet was the most active agent against Gram-negative pathogens with a well-balanced spectrum of activity.
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PMID:Comparative evaluation of orally active antibiotics against community-acquired pathogens: results of eight European countries. 875 Dec 63

Injuries and infectious respiratory, gastrointestinal and dermatologic diseases are common in day care settings. Most day care injuries are contusions, abrasions and cuts involving the head and extremities. Impact-absorbing surfaces under playground equipment, safely-proofing of all play areas, increased staff supervision, and staff and parental education might reduce injuries by as much as 75 percent. Respiratory illnesses are the most common day care infections. Chemoprophylaxis with rifampin is required for all close contacts of children infected with Haemophilus influenzae type B and Neisseria meningitidis. Diarrheal illness may be caused by viral pathogens, bacterial agents such as Shigella, Campylobacter or Salmonella, or parasitic infections caused by Giardia lamblia and Cryptosporidium. Strict hand-washing procedures, especially before food preparation and after toileting, may reduce diarrheal illness by 50 percent. Head lice (Pediculosis capitis) and scabies are common dermatologic infections spread by direct contact and through clothing, bedding and hair brushes. Screening and treating affected children with permethrin preparations and thoroughly washing bedding and clothing are necessary to stop outbreaks. Use of universal precautions for the handling of stool is essential to prevent the spread of both ordinary diarrheal illnesses and serious infections such as hepatitis A and B, human immunodeficiency virus and cytomegalovirus.
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PMID:The role of the family physician in the day care setting. 914 40

Antimicrobial resistance is becoming an important public health problem for both hospital- and community-acquired infections. In the hospital, infections caused by drug-resistant Staphylococcus aureus, Mycobacterium tuberculosis, enterococci, and a variety of Gram-negative rods are resulting in increased morbidity, mortality and costs, in part because of prolonged hospitalization and the use of more expensive antimicrobial agents. Drug-resistant, community-acquired infections are also causing important problems in both the developed and the developing world. Although the relative importance of specific pathogens varies with the geographical area, community-acquired pathogens including Salmonella, Shigella, Neisseria gonorrhoeae, Haemophilus influenzae and Streptococcus pneumoniae are causing both sporadic cases and outbreaks of drug-resistant illness. The emergence of antimicrobial resistance is being attributed to a series of societal, technological, environmental and microbial changes. These include increasing populations of susceptible hosts, international travel and commerce, changes in technology and industry, microbial adaptation and change, and the breakdown of public health measures. Addressing emerging problems and antimicrobial resistance will require enhanced surveillance, prudent use of existing antimicrobial drugs, development of new antimicrobial agents, increased emphasis on infection control and hygienic practices, effective disease control programs, better use of existing vaccines, and development of more and better vaccines.
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PMID:Epidemiological factors influencing the emergence of antimicrobial resistance. 918 44

In 1996 there were 65,024 notifications to the National Notifiable Diseases Surveillance System. The record high number of Ross River virus infection notifications was of particular note. The highest rates were recorded in Western Australia, where an outbreak was documented in the South West, and in Queensland. Most cases occurred in the late summer and early autumn months. The number of measles cases has continued to fall markedly following the outbreak in 1993 and 1994. Rubella notifications also fell in 1996. The number of cases of pertussis remained at a similar level to that recorded in recent years, the highest notification rate being recorded for children under the age of one year. A peak in late 1996 marked a resurgence in the pertussis epidemic which has continued into 1997. Notifications of Haemophilus influenzae type b continued to decline reaching a record low rate of 0.3 notifications per 100,000 population. For the enteric diseases, the number of cases of campylobacteriosis rose, with an annual adjusted notification rate of 100.4 per 100,000 population; more notifications were received for this disease than for any other in 1996. The number of hepatitis A cases also rose relative to 1995. This is a reversal of the trend observed in recent years when the notification rate fell. The number of cases of salmonellosis and shigellosis remained stable. Notifications for chlamydial infection and gonococcal infection rose relative to 1995, whilst those for syphilis fell.
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PMID:Australia's notifiable diseases status, 1996. Annual report of the National Notifiable Diseases Surveillance System. 933 2

The in-vitro activity of piperacillin/tazobactum which is not among the routinely tested antibiotic at the Public Health Bacteriology Laboratory, Parirenyatwa Hospital, Harare, Zimbabwe was evaluated for its activity against bacterial pathogens using the Kirby-Bauer disk diffusion method. Piperacillin/tazobactum showed superior in-vitro activity against both gram positive and gram negative bacteria when compared with routinely tested antibiotics such as gentamicin, erythromycin, tetracycline, penicillin, chloramphenicol, fusidic acid and clindamycin and the difference was statistically significant (p < 0.05). Ciprofloxacin showed in-vitro activity comparable to that of tazobactam/piperacillin. Specifically, 96% of gram positive isolates (comprising Streptococcus pyogenes, Staphylococcus aureus, coagulase negative staphylococci and Streptococcus pneumoniae were sensitive to piperacillin/tazobactam. For gram negative organisms, 98% of Haemophilus influenzae Shigella spp, Klebsiella spp were also sensitive to the combination. The broad spectrum of activity of piperacillin/tazobactam shows that the potential of the drug combination for the treatment of infections caused by diverse microorganisms should not be underestimated. We recommend its inclusion in routine antibiotic sensitivity testing in our hospital.
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PMID:In-vitro activity of piperacillin and tazobactam combination against clinically significant bacteria. 964 Aug 15

The penicillin family of antibiotics remains an important part of our antimicrobial armamentarium. In general, these agents have bactericidal activity, excellent distribution throughout the body, low toxicity, and efficacy against infections caused by susceptible bacteria. The initial introduction of aqueous penicillin G for treatment of streptococcal and staphylococcal infections was an important pharmacologic landmark. The emergence of penicillinase-producing Staphylococcus aureus prompted the development of the penicillinase-resistant penicillins (for example, methicillin, oxacillin, and nafcillin), in which an acyl side chain prevented disruption of the beta-lactamase ring. Subsequently, the aminopenicillins (ampicillin, amoxicillin, and bacampicillin) were developed because of the need for gram-negative antimicrobial activity. Their spectrum initially included Escherichia coli, Proteus mirabilis, Shigella, Salmonella, Listeria, Haemophilus, and Neisseria. The search for a penicillin with additional antimicrobial activity against the Enterobacteriaceae and Pseudomonas aeruginosa led to the development of the carboxypenicillins (carbenicillin and ticarcillin) and the ureidopenicillins (mezlocillin, azlocillin, and piperacillin). Finally, the combination of a beta-lactamase inhibitor (clavulanic acid, sulbactam, or tazobactam) and an aminopenicillin, ticarcillin, or piperacillin has further extended their antibacterial spectra by inhibiting certain beta-lactamases (non-group 1) of resistant bacteria. The development of an ideal penicillin that is rapidly bactericidal, nonsensitizing, nontoxic, bioavailable, and resistant to beta-lactamases and that has a high affinity for penicillin-binding proteins remains the goal.
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PMID:The penicillins. 1091 74

In 1997 there were 89,579 notifications to the National Notifiable Diseases Surveillance System. A notable feature of 1997 was the pertussis outbreak which peaked towards the end of the year and resulted in 10,668 cases being notified. The highest number of notifications received was for hepatitis C (unspecified) with 19,692 notifications; this is the first year for which data have been reported for New South Wales and South Australia for this disease category. The number of measles cases rose after the low number reported in 1996 but is still well below the number reported in the outbreak years of 1993 and 1994. Rubella notifications continued to decline in 1997. Notifications of Haemophilus influenzae type b appeared to have stabilised at a low rate, having declined markedly after introduction of the conjugated vaccine in 1992. The number of cases of campylobacteriosis remained steady after having risen for several years. Notifications of hepatitis A cases rose considerably, much of this being due to one outbreak in New South Wales. The number of cases of salmonellosis rose while shigellosis numbers dropped slightly. Notifications for chlamydial infection and gonococcal infection continued to rise, whilst those for syphilis continued to fall.
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PMID:Australia's notifiable diseases status, 1997. Annual report of the National Notifiable Diseases Surveillance System. 1009 94

The in vitro activity of trovafloxacin (TRV) has been evaluated in comparison with that of other antimicrobial agents against 5671 clinical isolates recovered by representative institutions of different provinces in our country. The resistance percentage to gentamicin and third generation cephalosporins among enterobacteriaceae was high: 17% and 16% respectively, with a considerable variation according to the analyzed species. The resistance to ciprofloxacin (CIP) and TRV affected approximately 9% of the isolates, without significant differences between both drugs. Fluoroquinolones (FQ) presented excellent activity on 166 isolates of Salmonella spp., 208 of Shigella flexneri and 76 of Shigella sonnei, where only one S.sonnei isolate was resistant to CIP, but susceptible to TRV. About half the isolates of Salmonella spp. and S.sonnei and almost all S.flexneri isolates were resistant to ampicillin, and more than 60% of Shigella spp. isolates were resistant to trimethoprim-sulfamethoxazole. A 41% of Staphylococcus aureus and 55% of coagulase-negative staphylococci isolates were resistant to oxacillin, presenting a highly associated multi-resistance. The resistance to FQ was also strongly related to oxacillin resistance, but the resistance to TRV was significantly lower than the CIP resistance: 9% vs 57% for S.aureus and 4% vs 41% for coagulase-negative staphylococci. A similar behavior was observed with Enterococcus spp., where 54% of the isolates were resistant to norfloxacin and only 13% were resistant to TRV. Neither Streptococcus pneumoniae (n = 193) nor Haemophilus influenzae (n = 139) isolates presented resistant to TRV.
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PMID:[In vitro activity of trovafloxacin, of other fluoroquinolones and of related antimicrobials against clinical isolates. Grupo colaborativo WHONET-Argentina]. 1043 49

The data are reviewed on the population structure and evolutionary dynamics of the nodule bacteria (rhizobia) which are among the most intensively studied microorganisms. High level of the population polymorphism was demonstrated for the rhizobia populations using the enzyme electrophoresis (MLEE profiles). The average value of Nei's coefficient of heterogeneity (H = 1 - sigma pi2 [n/(n - 1)]) were: 0.590 for rhizobia (Rhizobium, Bradyrhizobium), 0.368 for enterobacteria (Escherichia, Salmonella, Shigella) and 0.452 for pathogenic bacteria (Bordetella, Borrelia, Erysipelothrix, Haemophilus, Helicobacter, Listeria, Mycobacterium, Neisseria, Staphylococcus) populations. In spite of being devoid of the effective systems for the gene conjugative transfer, many rhizobia populations possess an essentially panmictic structure. However, the enterobacteria populations in which the gene transfer may be facilitated due to the conjugative F- and R-factors, usually display the clonal population structure. The legume host plant is proved to be a key factor that determines the high levels of polymorphism and of panmixis as well as high evolutionary rates of the symbiotic bacteria populations. The host may ensure: a) an increase in mutation and gene transfer frequencies; b) stimulation of the competitive (selective) processes in both symbiotic and free-living rhizobia populations. A "cyclic" model of the rhizobia microevolution is presented which allows to assess the inputs the interstrain competition for the saprophytic growth and for the host nodulation into evolution of a plant-associated rhizobia population. The nodulation competitiveness in the rhizobia populations is responsible for the frequency-dependent selection of the rare genotypes which may arise in the soil bacterial communities as a result of the transfer of symbiotic (sym) genes from virulent rhizobia strains to either avirulent rhizobia or to the other (saprophytic, phytopathogenic) bacteria. Therefore, the nodulation competitiveness may ensure: a) panmictic structure of the natural rhizobia populations; b) high taxonomic diversity of rhizobia which was apparently caused by a broad sym gene expansion in the soil bacterial communities. The kin selection models are presented which explain evolution of the "altruistic" (essential for the host plant, but not for the bacteria themselves) symbiotic traits (e.g., the ability for symbiotic nitrogen fixation and for differentiation into non-viable bacteroids) in the rhizobia populations. These models are based on preferential multiplication of the nitrogen-fixing clones either in planta (due to an elevated supply of the nitrogen-fixing nodules with photosynthates) or ex planta (due to a release of the rhizopines from the nitrogen-fixing nodules). Speaking generally, interactions with the host plants provide a range of mechanisms increasing a genetic heterogeneity and an evolutionary potential in the associated rhizobia populations.
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PMID:[The population genetics of nodule bacteria]. 1086 62


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