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evidence for transfer of cmy-2 ampc beta-lactamase plasmids between escherichia coli and salmonella isolates from food animals and humans.escherichia coli is an important pathogen that shows increasing antimicrobial resistance in isolates from both animals and humans. our laboratory recently described salmonella isolates from food animals and humans that expressed an identical plasmid-mediated, ampc-like beta-lactamase, cmy-2. in the present study, 59 of 377 e. coli isolates from cattle and swine (15.6%) and 6 of 1,017 (0.6%) isolates of human e. coli from the same geographic region were resistant to both cephamycins and extended- ...200111557460
formation of the 1,n2-glyoxal adduct of deoxyguanosine by phosphoglycolaldehyde, a product of 3'-deoxyribose oxidation in dna.oxidation of deoxyribose in dna results in the formation of a variety of electrophilic products that have the potential to react with nucleobases to form adducts. we now report that 2-phosphoglycolaldehyde, a model for the 3'-phosphoglycolaldehyde residue generated by 3'-oxidation of deoxyribose in dna, reacts with dg and dna to form the diastereomeric 1,n2-glyoxal adducts of dg, 3-(2-deoxy-beta-d-erythro-pentofuransyl)-6,7-dihydro-6,7-dihydroxyimidazo[1,2-a]purine-9(3h)-one. the glyoxal adducts ...200111559039
dual mode recognition of two isoacceptor trnas by mammalian mitochondrial seryl-trna synthetase.animal mitochondrial translation systems contain two serine trnas, corresponding to the codons agy (y = u and c) and ucn (n = u, c, a, and g), each possessing an unusual secondary structure; trna(gcu)(ser) (for agy) lacks the entire d arm, whereas trna(uga)(ser) (for ucn) has an unusual cloverleaf configuration. we previously demonstrated that a single bovine mitochondrial seryl-trna synthetase (mt serrs) recognizes these topologically distinct isoacceptors having no common sequence or structure ...200111577083
titration of low k(d) binding sites: binding of arginine analogs to nitric oxide synthases.spectrophotometrically monitored ligand titration is an important method for the determination of equilibrium dissociation constants (k(d)) from nitric oxide synthases (nos). low k(d) sites such as the tetrahydrobiopterin and arginine binding sites present difficulties in that experiments often require enzyme concentrations of the same magnitude as the k(d). an analytical method based on computer simulation is described that allows the estimation of k(d) values without an independent means of mo ...200111587559
overexpression of human insulin-like growth factor-i promotes new tissue formation in an ex vivo model of articular chondrocyte transplantation.articular cartilage, the tissue that forms the gliding surface of joints, has a poor regenerative capacity. insulin-like growth factor-i (igf-i) is a polypeptide that is anabolic and mitogenic for cartilage. transfection of articular chondrocytes with an expression plasmid vector containing the cdna for human igf-i under the control of the cytomegalovirus promoter/enhancer led to expression of the transgene and synthesis of biologically relevant amounts of igf-i protein. transplantation of trans ...200111593356
structural and functional characterization of human nad kinase.nadp is essential for biosynthetic pathways, energy, and signal transduction. its synthesis is catalyzed by nad kinase. very little is known about the structure, function, and regulation of this enzyme from multicellular organisms. we identified a human nad kinase cdna and the corresponding gene using available database information. a cdna was amplified from a human fibroblast cdna library and functionally overexpressed in escherichia coli. the obtained cdna, slightly different from that deposit ...200111594753
effect of irradiation temperature on inactivation of escherichia coli o157:h7 and staphylococcus aureus.the resistance of escherichia coli o157:h7 and staphylococcus aureus in ground beef to gamma radiation was significantly (p < 0.05) higher at subfreezing temperatures than above freezing. ground beef was inoculated (ca. 2 x 10(8) cfu/g) with five isolates of either e. coli o157:h7 or s. aureus and subdivided into 25-g samples, vacuum packaged in barrier pouches, and tempered to 20, 12, 4, 0, -4, -12, -20, -30, -40, or -76 degrees c before gamma irradiation. the studies were repeated twice. the d ...200111601718
bacteremia associated with naturally occuring acute coliform mastitis in dairy cows.to determine the incidence of bacteremia in dairy cows with naturally occurring acute coliform mastitis (acm) with a wide range of disease severity.200111601796
rotavirus 2/6 virus-like particles administered intranasally in mice, with or without the mucosal adjuvants cholera toxin and escherichia coli heat-labile toxin, induce a th1/th2-like immune response.we investigated the rotavirus-specific lymphocyte responses induced by intranasal immunization of adult balb/c mice with rotavirus 2/6 virus-like particles (2/6-vlps) of the bovine rf strain, by assessing the profile of cytokines produced after in vitro restimulation and serum and fecal antibody responses. the cytokines produced by splenic cells were first evaluated. intranasal immunization with 50 microg of 2/6-vlps induced a high serum antibody response, including immunoglobulin g1 (igg1) and ...200111602741
e. coli methionine sulfoxide reductase with a truncated n terminus or c terminus, or both, retains the ability to reduce methionine sulfoxide.the monomeric peptide methionine sulfoxide reductase (msra) catalyzes the irreversible thioredoxin-dependent reduction of methionine sulfoxide. the crystal structure of msras from escherichia coli and bos taurus can be described as a central core of about 140 amino acids that contains the active site. the core is wrapped by two long n- and c-terminal extended chains. the catalytic mechanism of the e. coli enzyme has been recently postulated to take place through formation of a sulfenic acid inte ...200111604533
a novel locus of enterocyte effacement (lee) pathogenicity island inserted at phev in bovine shiga toxin-producing escherichia coli strain o103:h2.we describe a locus of enterocyte effacement (lee) which is part of a new pathogenicity island (pai) detected in the bovine shiga toxin-producing escherichia coli strain rw1374 (o103:h2). this pai is at least 80 kb in size and inserted in the vicinity of the phev trna gene at 67 min of the e. coli chromosome. furthermore, the pai differs from the previously described lees by unique flanking regions at both sides, which harbor one copy each of an insertion element in an inverted orientation that ...200111682182
colostral whey concentrate supplement increases complement activity in the sera of neonatal calves.we evaluated the effect of a commercial bovine colostral whey on the complement-mediated immune responses of calves. two groups of neonatal calves were fed, in addition to whole milk (wm) and pooled colostrum (pc), different amounts of a commercial immunoglobulin concentrate made from pooled colostral whey (ig-c) for the first two feedings post natum. the control group was fed wm and pc only. serum samples were obtained at the ages of 2, 7, 14 and 30 d. bacteriolytic activity against complement- ...200111694039
ancestral divergence, genome diversification, and phylogeographic variation in subpopulations of sorbitol-negative, beta-glucuronidase-negative enterohemorrhagic escherichia coli o157.the o157:h7 lineage of enterohemorrhagic escherichia coli is a geographically disseminated complex of highly related genotypes that share common ancestry. the common clone that is found worldwide carries several markers of events in its evolution, including markers for acquisition of virulence genes and loss of physiological characteristics, such as sorbitol fermentation ability and beta-glucuronidase production. populations of variants that are distinct with respect to motility and the sorbitol ...200111698378
prevalence of foodborne pathogens in bulk tank milk.bulk tank milk from 131 dairy herds in eastern south dakota and western minnesota was examined for the presence of for foodborne pathogens. campylobacter jejuni, shiga-toxin producing escherichia coli, listeria monocytogenes, salmonella spp., and yersinia enterocolitica were detected in 9.2, 3.8, 4.6, 6.1, and 6.1% of bulk tank milk samples, respectively. thirty-five of 131 (26.7%) bulk tank milk samples contained one or more species of pathogenic bacteria. isolates of salmonella belonged to gro ...200111699446
analysis of the inhibition of mammalian thioredoxin, thioredoxin reductase, and glutaredoxin by cis-diamminedichloroplatinum (ii) and its major metabolite, the glutathione-platinum complex.several studies have demonstrated a correlation between cellular toxicity of cis-diamminedichloroplatinum (ii) (cisplatin, cddp) and inhibited intracellular activity of the thioredoxin system, i.e., thioredoxin (trx), thioredoxin reductase (trxr), and nadph. conversely, increased cellular activity of the trx system confers resistance to cddp. in this study, we have analyzed the interaction of cddp with trx and trxr in order to clarify the mechanism. the inhibition with time-dependent kinetics by ...200111705695
prevalence of e coli o157 in dairy cows presented for slaughter in victoria. 200111712712
endometritis in postparturient cattle associated with bovine herpesvirus-4 infection: 15 cases.suppurative, ulcerative endometritis associated with bovine herpesvirus-4 (bhv-4) infection was identified in 15 postparturient dairy cows from 5 separate dairies. characteristic eosinophilic to amphophilic intranuclear viral inclusion bodies were identified within degenerate endometrial lining epithelium and endothelial cells. bovine herpesvirus-4 was confirmed as the etiology by a combination of fluorescent antibody assays, viral isolation, heminested pcr, ultrastructural examination of the ut ...200111724141
contamination of beef chucks with escherichia coli during carcass breaking.samples were obtained by swabbing the whole of the chuck portion on each of the first 500 sides that entered a beef carcass breaking process and the whole of the outer surface of each of the chuck primal cuts that were prepared from those portions. swabs obtained from groups of 10 sides or cuts that entered or emerged from the process consecutively were combined, and the coliforms and escherichia coli recovered from each group were enumerated. coliforms and e. coli were recovered only sporadical ...200111726167
sensitivity of shiga toxin-producing escherichia coli (stec) strains for colicins under different experimental conditions.twenty escherichia coli strains producing well-characterised colicins were tested for their inhibitory activity against five shiga toxin-producing e. coli (stec) strains using different media under aerobic and anaerobic conditions. the five stec strains used were of serotype o26, o111, o128, o145 and o157:h7 which are frequently isolated serotypes associated with disease in humans. the main route of infection for humans is through the eating of badly cooked or handled beef. the major reservoir f ...200111731144
sample preparation methods for pcr detection of escherichia coli o157:h7, salmonella typhimurium, and listeria monocytogenes on beef chuck shoulder using a single enrichment medium.to improve the utility of the polymerase chain reaction (pcr) for food samples, methods for preparing template dna were developed to remove pcr inhibitors. beef chuck shoulder medallions, artificially contaminated, individually or in combination, with escherichia coli serotype o157:h7 strain fsis 45753-35, salmonella typhimurium dt104 strain 13hp, or listeria monocytogenes strain scott a at concentrations of 10, 1 and 0.5 cfu/cm(2)were swabbed with a sponge, and the sponges were enriched for 18 ...200111735298
regulation of photoreceptor phosphodiesterase (pde6) by phosphorylation of its inhibitory gamma subunit re-evaluated.phosphorylation of the inhibitory gamma subunit (pgamma) of rod cgmp phosphodiesterase (pde6) has been reported to turn off visual excitation without the requirement for inactivation of the photoreceptor g-protein transducin. we evaluated the significance of pgamma phosphorylation for pde6 regulation by preparing pgamma stoichiometrically phosphorylated at thr(22) or at thr(35). phosphorylation of pgamma at either residue caused a minor decrease--not the previously reported increase--in the abil ...200211741972
factors contributing to the emergence of escherichia coli o157 in africa.in 1992, a large outbreak of bloody diarrhea caused by escherichia coli o157 infections occurred in southern africa. in swaziland, 40,912 physician visits for diarrhea in persons ages >5 years were reported during october through november 1992. this was a sevenfold increase over the same period during 1990-91. the attack rate was 42% among 778 residents we surveyed. female gender and consuming beef and untreated water were significant risks for illness. e. coli o157:nm was recovered from seven a ...200111747693
prevalence and genetic profiling of virulence determinants of non-o157 shiga toxin-producing escherichia coli isolated from cattle, beef, and humans, calcutta, india.we investigated the prevalence of shiga toxin-producing escherichia coli (stec) in hospitalized diarrhea patients in calcutta, india, as well as in healthy domestic cattle and raw beef samples collected from the city's abattoir. multiplex polymerase chain reaction using primers specific for stx1 and stx2 detected stec in 18% of cow stool samples, 50% of raw beef samples, and 1.4% and 0.6% of bloody and watery stool samples, respectively, from hospitalized diarrhea patients. various virulence gen ...200211749749
molecular analysis of chromosomally florfenicol-resistant escherichia coli isolates from france and germany.the aim of this study was to analyse chromosomally florfenicol-resistant escherichia coli isolates for their genetic relatedness, and also for the presence of the flor gene and its adjacent regions, in order to compare these regions with those associated with a flor gene located on a conjugative plasmid from e. coli. twenty-two bovine e. coli from france and germany were examined. florfenicol resistance was determined by mic determination. the presence of the flor gene was confirmed by hybridiza ...200211751766
prevalence and characteristics of shigatoxin-producing escherichia coli and listeria monocytogenes strains isolated from minced meat in switzerland.a total of 400 minced meat samples from 240 small butcheries in switzerland were collected and analysed for the presence of shigatoxin-producing e. coli (stec) and listeria monocytogenes. the samples comprised 211 samples of minced beef and 189 samples of minced pork. shigatoxin-producing e. coli was isolated from 7/400 (1.75%) samples. in particular, 5/211 (2.3%) minced beef samples and 2/189 (1%) minced pork samples were contaminated. serotyping of the seven strains yielded five different sero ...200111759763
effect of selenium and vitamin e on antibody production by dairy cows vaccinated against escherichia coli.sixty clinically healthy holstein cows were randomly assigned to one of four groups according to their age and parity and vaccinated in late pregnancy (day 190) with a multivalent vaccine against escherichia coli. the 15 cows in the first group (see) were injected intramuscularly with a solution of sodium selenite (0.1 mg se/kg bodyweight) and vitamin e (alpha-tocopherol acetate, 8 u/kg bodyweight), the cows in the second group (se) received only selenium and the cows in the third group (e) rece ...200111764325
evaluation of an antimicrobial-impregnated continuous ambulatory peritoneal dialysis catheter for infection control in rats.infection is the most serious complication arising in long-term continuous ambulatory peritoneal dialysis (capd), specifically peritonitis and exit-site infection. the initial weeks after implantation is the crucial period during which bacterial colonization of the catheter results in maximal morbidity, with staphylococcus aureus being the most virulent organism. we developed an antimicrobial-impregnated capd catheter by impregnating the cuff and tubing with chlorhexidine, silver sulfadiazine, a ...200211774116
rice (oryza sativa) contains a novel isoform of glutamate decarboxylase that lacks an authentic calmodulin-binding domain at the c-terminus.we have isolated full-length cdnas for two distinct isoforms of glutamate decarboxylase (gad), designated osgad1 and osgad2 from a rice shoot cdna library. open reading frames found in osgad1 and osgad2 cdnas encode putative proteins of 501 (56.7 kda) and 500 amino acids (55.6 kda), respectively. they show 69% identity to each other and 67-78% identity to dicotyledonous counterpart sequences determined so far. comparative analysis of relevant genomic clones obtained from the rice genomic library ...200111779628
design and assembly of solid-phases for the effective recovery of nanoparticulate bioproducts in fluidised bed contactors.practical recovery of nanoparticulate bioproducts from suspension feedstocks has been studied in batch, fixed bed and fluidised bed adsorptive contactors. the performance of five discrete configurations of adsorbent solid phase has been critically evaluated in the anion exchange recovery of mg quantities of bsa nanoparticles. these have served as surrogate size mimics of less easily sourced viral and plasmid gene therapy vectors, characterised by high value and a shortage of supply in quantities ...200111787793
design of expanded bed supports for the recovery of plasmid dna by anion exchange adsorption.in this study we detail the rational design of new chromatographic adsorbents tailored for the capture of plasmid dna. features present on current chromatographic supports that can significantly enhance plasmid binding capacity have been identified in packed bed chromatography experiments and blueprints for improved expanded bed adsorbents have been put forward. the characterisation and testing of small (20-40 microm) high density (>3.7 g cm(-3)) pellicular expanded bed materials functionalised ...200111787795
expression in escherichia coli, purification and kinetic characterization of human heparan sulfate 3-o-sulfotransferase-1.heparan sulfate (hs) glycosaminoglycans are a structurally diverse class of complex biomolecules that modulate many important events at the cell surface and within the extracellular matrix and whose structural heterogeneity derives largely from the sequence-specific n- and o-sulfations catalyzed by an extensive repertoire of sulfating enzymes. we have expressed the human heparan sulfate 3-ost-1 isoform in escherichia coli and subsequently purified a soluble, active enzyme. to assess its function ...200211811991
bacterial expression and purification of recombinant bovine fab fragments.we have previously described a recombinant phagemid expression vector, pcombov, designed for the production of native sequence bovine monoclonal antibodies (mab) generated by antibody phage display. bovine mab fab fragments isolated from libraries constructed using pcombov in escherichia coli strain xl1-blue, which is routinely used for antibodies expressed on the surface of phage, were expressed at very low yields. therefore, a study was undertaken to determine optimal growth conditions for max ...200211812221
a cooperia punctata gene family encoding 14 kda excretory-secretory antigens conserved for trichostrongyloid nematodes.a polymorphic set of 14 kda excretory-secretory (e-s) antigen-encoding cdnas, with similarity to a previously characterized 15 kda e-s antigen of haemonchus contortus, was cloned from cooperia punctata. five cdnas encoding predicted proteins of 70-80% identity were sequenced. genomic analyses of individuals proved the existence of three 14 kda e-s antigen-encoding genes, excluding that the differences reflected polymorphisms between individuals in a population. southern blots indicated the prese ...200111814050
inhibition of enteropathogenic escherichia coli (epec) adherence to hep-2 cells by bovine colostrum and milk.enteropathogenic escherichia coli (epec) is the main etiological agent of infantile diarrhea in brazil and other developing countries. human milk iga protects newborn intestinal mucosa by inhibiting bacterial adhesion to epithelial cells and this effect is shown by in vitro assays of epec adhesion to hep-2 cultured cells. bovine milk, if effective in promoting this protection, could be an useful tool in the absence of the natural breastfeeding, in high-risk nurseries or in hospital infections.200111834181
recognition by tryptophanyl-trna synthetases of discriminator base on trnatrp from three biological domains.to study the recognition by tryptophanyl-trna synthetase (trprs) of trna(trp) discriminator base, mutations were introduced into the discriminator base of bacillus subtilis, archeoglobus fulgidus, and bovine trna(trp), representing the three biological domains. when b. subtilis, a. fulgidus, and human trprs were used to acylate these trna(trp), two distinct preference profiles regarding the discriminator base of different trna(trp) substrates were found: g>a>u>c for b. subtilis trprs, and a>c>u> ...200211834741
direct recovery of glutathione s-transferase by expanded bed adsorption: anion exchange as an alternative to metal affinity fusions.the use of expanded beds of ion-exchange adsorbents for the direct recovery of a recombinant intracellular protein, glutathione s-transferase (gst), from unclarified escherichia coli homogenates is described. the results form the basis for a comparison between this approach for purifying gst and a chelating fusion strategy and highlight the need to consider the additional costs entailed by these more-complicated approaches. the separation performance was investigated with respect to choice of an ...200211835138
molecular typing techniques to characterize the development of a lactic acid bacteria community on vacuum-packaged beef.the development of a community of lactic acid bacteria from vacuum-packaged beef was investigated during a 6-week storage trial at 2 degrees c. the lactic acid bacteria population was monitored by using molecular techniques to identify a random sample of isolates at biweekly intervals during the storage trial. the polymerase chain reaction and a randomly amplified polymorphic dna technique were used to identify and distinguish populations of lactic acid bacteria that developed during the storage ...200211843419
time-resolved step-scan fourier transform infrared spectroscopy of the co adducts of bovine cytochrome c oxidase and of cytochrome bo(3) from escherichia coli.we have used cryogenic difference ftir and time-resolved step-scan fourier transform infrared (tr-ftir) spectroscopies to explore the redox-linked proton-pumping mechanism of heme-copper respiratory oxidases. these techniques are used to probe the structure and dynamics of the heme a(3)-cu(b) binuclear center and the coupled protein structures in response to the photodissociation of co from heme fe and its subsequent binding to and dissociation from cu(b). previous cryogenic (80 k) ftir co photo ...200211851414
chemically mediated site-specific proteolysis. alteration of protein-protein interaction.the design and synthesis of a novel iodine-labile serine protease inhibitor was realized by the use of an ecotin analogue containing allylglycine at position 84 in lieu of methionine. allylglycine-containing ecotins were synthesized by in vitro translation of the ecotin gene containing an engineered nonsense codon (tag) at the positions of interest. a misacylated suppressor trna activated with the unnatural amino acid allylglycine was employed for the suppression of the nonsense codons in a cell ...200211851428
development of a sandwich elisa and comparison with pcr for the detection of f11 and f165 fimbriated escherichia coli isolates from septicaemic disease in farm animals.the p fimbriae f11 and f165 that have been demonstrated on escherichia coli septicaemic strains in poultry and calves, respectively, possess a nearly identical major subunit that demonstrates a serological cross-reaction. a polyclonal antibody-based sandwich elisa (selisa) that was specific for both f11 and f165 fimbriated strains was compared with a pcr method to detect f11/f165 fimbriated strains, in a collection of e. coli strains isolated from diseased animals. of 298 isolates tested, 36 wer ...200211852192
analysis of a multicomponent thermostable dna polymerase iii replicase from an extreme thermophile.this report takes a proteomic/genomic approach to characterize the dna polymerase iii replication apparatus of the extreme thermophile, aquifex aeolicus. genes (dnax, hola, and holb) encoding the subunits required for clamp loading activity (tau, delta, and delta') were identified. the dnax gene produces only the full-length product, tau, and therefore differs from escherichia coli dnax that produces two proteins (gamma and tau). nonetheless, the a. aeolicus proteins form a taudeltadelta' comple ...200211859073
[detection of escherichia coli strains harboring pathogenicity island of yersinia enterolitica in diarrheal patients and animals in china].to investigate the prevalence of escherichia coil strains harboring high pathogenicity island of yersinia enterocolitica in diarrhea patients, animals, food samples and resulted clinical symptoms.200011860774
expression of receptors for verotoxin 1 from escherichia coli o157 on bovine intestinal epithelium.human enterohaemorrhagic escherichia coli (ehec) infection most commonly arises, either directly or indirectly, from cattle, which act as a reservoir host for these bacteria. in man, ehec disease can be severe, whereas ehec do not normally cause disease in cattle. verotoxins (vts) are the main virulence factors in human disease but no role for vt has been ascribed in cattle; however, this study shows for the first time that vt receptor is expressed by the bovine intestinal tract. vt bound to cry ...200211865842
transfer of multiple drug resistance plasmids between bacteria of diverse origins in natural microenvironments.plasmids harboring multiple antimicrobial-resistance determinants (r plasmids) were transferred in simulated natural microenvironments from various bacterial pathogens of human, animal, or fish origin to susceptible strains isolated from a different ecological niche. r plasmids in a strain of the human pathogen vibrio cholerae o1 e1 tor and a bovine escherichia coli strain were conjugated to a susceptible strain of the fish pathogenic bacterium aeromonas salmonicida subsp. salmonicida in marine ...199411865872
pharmacokinetics of ceftiofur in plasma and uterine secretions and tissues after subcutaneous postpartum administration in lactating dairy cows.a study was conducted to measure concentrations of potentially active ceftiofur derivatives, in plasma, in uterine tissues (endometrium and caruncles) and in uterine secretions at different time points after a single subcutaneous administration of ceftiofur hydrochloride (excenel rtu sterile suspension) at the dose of 1 mg/kg body weight in holstein-friesian dairy cows. the animals (n=4) were injected within 24 h of calving, after expulsion of the foetal membranes. plasma, lochial fluid, caruncl ...200211874524
influence of puerperal uterine infection on uterine involution and postpartum ovarian activity in dairy cows.this article presents the results of a clinical trial designed to study the effect of puerperal uterine infection on uterine involution and on ovarian activity in dairy cows, monitored twice weekly from parturition until the sixth week postpartum (wpp). infection significantly retarded uterine involution assessed by the uterine body diameter and a score of intrauterine fluid volume (iufv). by the sixth wpp, cows with normal puerperium (controls) and cows that showed mild puerperal endometritis h ...200211882243
clinical and bacteriological aspects on the use of oxytetracycline and flunixin in primiparous cows with induced retained placenta and post-partal endometritis.retention of the fetal membranes and post-partal endometritis (rfm) are common problems in dairy cows. treatment often includes manual removal of the placenta in combination with antibiotic treatment. earlier studies have shown that cows with endometritis post-partum have a strong tendency to recover spontaneously. the present study focused on treatments of post-partal endometritis with the prostaglandin synthesis inhibitor, flunixin (f) either alone or combined with oxytetracycline (t). the stu ...200111885742
escherichia coli o157 infections and unpasteurised milk.we report on two children with escherichia coli o157 infection, one of whom developed haemolytic uraemic syndrome (hus). both had drunk raw cows or goats milk in the week before their illness. molecular subtyping identified a sorbitol fermenting escherichia coli o157:h isolate from a dairy cow. this isolate differed from shiga toxin producing o157:h strains isolated from the 6 year old boy with hus. this result underlines the need to search for other causes of infection, despite documented con ...200111891383
characterization of a brain-enriched chaperone, mrj, that inhibits huntingtin aggregation and toxicity independently.molecular chaperones are involved in a wide range of cellular events, such as protein folding and oligomeric protein complex assembly. dnak- and dnaj-like proteins are the two major classes of molecular chaperones in mammals. recent studies have shown that dnaj-like family proteins can inhibit polyglutamine aggregation, a hallmark of many neurodegenerative diseases, including huntington's disease (hd). although most dnaj-like proteins studied are ubiquitously expressed, some have restricted expr ...200211896048
effect of apoptosis on phagocytosis, respiratory burst and cd18 adhesion receptor expression of bovine neutrophils.polymorphonuclear neutrophil leukocytes (pmn) play an important role in intramammary defense against infections by escherichia coli. during mastitis, pmn are confronted with various inflammatory mediators that can modulate their function. in severely diseased cows, increased concentrations of lipopolysaccharide (lps) and tumor necrosis factor (tnf)-alpha (tnf-alpha) are detected in plasma. binding of lps to membrane bound cd14 molecules on monocytes cause release of inflammatory mediators such a ...200211900963
[molecular epidemiological investigation of vero toxin-producing escherichia coli (vtec) isolated from diarrhea patients and dairy cattle].to elucidate the source and route of vtec infection, we performed pulse field gel electrophoresis (pfge) an 50 isolates from human diarrhea typed as serotypes o157, o111, and o26, which were very frequently isolated from patients with vtec infection between 1986 and 1997, and 32 isolates from dairy cattle, a total of 82 isolates. the isolates were genetically analyzed based on the electrophoresis patterns of dna, and a phylogenetic tree was prepared. the isolates were classified based on similar ...200211905004
thermodynamics of single peptide bond cleavage in bovine pancreatic trypsin inhibitor (bpti).a major goal of this paper was to estimate a dynamic range of equilibrium constant for the opening of a single peptide bond in a model protein, bovine pancreatic trypsin inhibitor (bpti). ten mutants of bpti containing a single xaa-->met substitution introduced in different parts of the molecule were expressed in escherichia coli. the mutants were folded, purified to homogeneity, and cleaved with cyanogen bromide to respective cleaved forms. conformation of the intact mutants was similar to the ...200211910035
apoptosis of bovine neutrophils during mastitis experimentally induced with escherichia coli or endotoxin.to determine whether apoptosis of neutrophils was accelerated during mastits experimentally induced by use of escherichia coli or e coli endotoxin and whether differences were apparent in the response to e coli or endotoxin.200211911583
engineered recombinant enteropeptidase catalytic subunit: effect of n-terminal modification.enteropeptidase (enterokinase) is a serine protease highly specific for recognition and cleavage of the target sequence of asp-asp-asp-asp-lys (d4k). the three-dimensional structure of the enteropeptidase shows that the n-terminal amino acid is buried inside the protein providing molecular interactions necessary to maintain the conformation of the active site. to determine the influence of the n-terminal amino acid of enteropeptidase light chain (ek(l)) on the enzymatic activity, we constructed ...200211913964
shedding of escherichia coli o157:h7 in dairy cattle housed in a confined environment following waterborne inoculation.a study of escherichia coli o157:h7 transmission and shedding was conducted with bull calves housed in individual pens within a confined environment. for comparative purposes, the numbers and duration of e. coli o157:h7 shedding in naturally infected calves were monitored after a single purchased calf (calf 156) tested positive prior to inoculation. during the next 8 days, the calves in adjacent pens and a pen directly across a walkway from calf 156 began to shed this serotype o157:h7 strain. fi ...200211916717
first isolation of the enterohaemorrhagic escherichia coli o145:h- from cattle in feedlot in argentina.enterohaemorrhagic escherichia coli (ehec) is considered to be common cause of haemorrhagic colitis (hc), thrombotic thrombocytopenic purpura and haemolytic uraemic syndrome (hus) in humans. in a previous paper, we have demonstrated that ehec are commonly found in the intestines of livestock. infections in humans are, in part, a consequence of consumption of undercooked meat or raw milk. argentina has one of the highest records of hus (300-400 cases/year; 22/100,000 children under 4 years of age ...200211936956
testing of a chemiluminescence enzyme immunoassay for selective detection of e. coli o157 from ground beef samples.the aim of this study was to evaluate a chemiluminescence enzyme immunoassay (clia) developed for the detection of e. coli o157:h7, using different e. coli o157 serotypes. the sensitivity and specificity of the kit were determined from the tenfold dilutions of the 24-hour broth cultures of the test strains. according to the results obtained in this trial, the sensitivity of the kit is 10(3)-10(4) cells ml-1, and it is specific for e. coli o157. twenty-five g ground raw beef samples were prepared ...200111942117
increase in milk metalloproteinase activity and vascular permeability in bovine endotoxin-induced and naturally occurring escherichia coli mastitis.an endotoxin-induced mastitis model was used to study permeability changes associated with increased milk matrix metalloproteinase (mmp) activity in early inflammation. one quarter of two cows was inoculated with endotoxin (escherichia coli 055:b5). blood, milk, and whey were collected before and repeatedly after inoculation for 48 h. the profile and amounts of gelatinolytic mmps were determined by zymography; gelatinase a (72 kd mmp-2) and gelatinase b (92 kd mmp-9) were identified by western i ...200211943315
an infrared study of the thermal and ph stabilities of the gpi-alkaline phosphatase from bovine intestine.alkaline phosphatase (ec 3.1.3.1) from bovine intestine mucosa (biap) is a homodimeric metalloenzyme, which hydrolyses nonspecifically phosphate monoesters at alkaline ph with release of inorganic phosphate and alcohol. biap is either soluble (sbiap) or membrane-anchored by a glycosylphosphatidylinositol moiety (gpi-biap). this anchor might have some contribution in the stabilization of the gpi-linked protein structure. our purpose was to study the role of the anchor by using two parameters, the ...200211944895
protein nucleation and crystallization by homologous protein thin film template.a new method of protein nucleation and crystallization based on langmuir-blodgett technology is here utilized for the template stimulation of crystal growth of so far non-crystallized proteins. microcrystals (60-120 microm) of bovine cytochrome p450scc and human protein kinase ckii alpha subunit were obtained with use of the homologous protein thin film template by vapor diffusion modified hanging drop method. the induction of microcrystals nucleation by the thin template confirms in the two dif ...200211948680
evaluation of the efficacy of an internal teat sealer during the dry period.the efficacy of an internal dry period teat sealer containing bismuth subnitrate (product a; teatseal, cross vetpharm group ltd, ireland) was compared with a long-acting antibiotic preparation containing cephalonium (product b; cepravin dry cow, schering-plough ltd, uk), by assessing the number of new intramammary infections (imi) acquired during the dry period and the number of cases of clinical mastitis during the first 100 d of lactation. selection of study animals was based on historical dat ...200211949859
detection of escherichia coli o157:h7 in 10- and 25-gram ground beef samples with an evanescent-wave biosensor with silica and polystyrene waveguides.a portable evanescent-wave fiber-optic biosensor was used to detect escherichia coli o157:h7 in seeded 10- and 25-g ground beef samples. the biosensor works by launching light from a 635-nm laser diode into specially designed optical fiber probes, generating an evanescent field that extends approximately 1,000 nm from the fiber surface. fluorescent molecules within the evanescent field are excited, and a portion of their emission recouples into the fiber probe. the return path emission is transp ...200211952206
vaccination of pregnant dams with intimin(o157) protects suckling piglets from escherichia coli o157:h7 infection.cattle are important reservoirs of enterohemorrhagic escherichia coli (ehec) o157:h7 that cause disease in humans. both dairy and beef cattle are asymptomatically and sporadically infected with ehec. our long-term goal is to develop an effective vaccine to prevent cattle from becoming infected and transmitting ehec o157:h7 to humans. we used passive immunization of neonatal piglets (as a surrogate model) to determine if antibodies against ehec o157 adhesin (intimin(o157)) inhibit ehec colonizati ...200211953378
genomic subtraction to identify and characterize sequences of shiga toxin-producing escherichia coli o91:h21.to identify shiga toxin-producing escherichia coli genes associated with severe human disease, a genomic subtraction technique was used with hemolytic-uremic syndrome-associated o91:h21 strain ch014 and o6:h10 bovine strains. the method was adapted to the shiga toxin-producing e. coli genome: three rounds of subtraction were used to isolate dna fragments specific to strain ch014. the fragments were characterized by genetic support analysis, sequencing, and hybridization to the genome of a collec ...200211976103
design, production, and characterization of recombinant neocarzinostatin apoprotein in escherichia coli.neocarzinostatin (ncs) is the first discovered anti-tumor antibiotic having an enediyne-containing chromophore and an apoprotein with a 1:1 complex. an artificial gene library for ncs apoprotein (apo-ncs) production in escherichia coli was designed and constructed on a phage-display vector, pjufo. the recombinant phages expressing pre-apo-ncs protein were enriched with a mouse anti-apo-ncs monoclonal antibody, 1c7d4. the apo-ncs gene (encsa) for e. coli was successfully cloned, and then re-clone ...200211983081
pathogenic shiga toxin-producing escherichia coli in the intestine of calves.the purpose of this study was to compare the pathological effects of shiga toxin-producing escherichia coli (stec) that vary in their association with bovine and human disease. shiga toxin-producing e. coli of serotypes associated with both dysentery in calves and hemolytic uremic syndrome (hus) in humans (o5:h-, o26:h11, o111:h-,o113:h21) were compared with o157:h7 stec, which are associated with hus in humans but not with disease in calves. the stec were administered orally to 80 day-old chick ...200211989736
biofilm bacteria: formation and comparative susceptibility to antibiotics.the calgary biofilm device (cbd) was used to form bacterial biofilms of selected veterinary gram-negative and gram-positive pathogenic bacteria from cattle, sheep, pigs, chicken, and turkeys. the minimum inhibitory concentration (mic) and minimum biofilm eradication concentration (mbec) of ampicillin, ceftiofur, cloxacillin, oxytetracycline, penicillin g, streptomycin, tetracycline, enrofloxacin, erythromycin, gentamicin, tilmicosin, and trimethoprim-sulfadoxine for gram-positive and -negative b ...200211989739
in vitro expression of tumor necrosis factor-alpha, interleukin 1beta, and interleukin 8 mrna by bovine macrophages following exposure to porphyromonas levii.the objective was to evaluate the pro-inflammatory response of bovine macrophages towards porphyromonas levii, an etiologic agent of acute interdigital phlegmon, by evaluating the mrna expression of tumor necrosis factor-alpha (tnf-alpha), interleukin 1beta (il-1beta), and interleukin 8 (il-8). bovine macrophages detect the presence of bacteria, such as p. levii, and respond by upregulating transcription of the genes for pro-inflammatory cytokines tnf-alpha and il-1beta in addition to the neutro ...200211989740
e. coli aconitase b structure reveals a heat-like domain with implications for protein-protein recognition.the major bifunctional aconitase of escherichia coli (acnb) serves as either an enzymic catalyst or a mrna-binding post-transcriptional regulator, depending on the status of its iron sulfur cluster. acnb represents a large, distinct group of gram-negative bacterial aconitases that have an altered domain organization relative to mitochondrial aconitase and other aconitases. here the 2.4 a structure of e. coli acnb reveals a high degree of conservation at the active site despite its domain reorgan ...200211992126
hsc66 substrate specificity is directed toward a discrete region of the iron-sulfur cluster template protein iscu.hsc66 and hsc20 comprise a specialized chaperone system important for the assembly of iron-sulfur clusters in escherchia coli. only a single substrate, the fe/s template protein iscu, has been identified for the hsc66/hsc20 system, but the mechanism by which hsc66 selectively binds iscu is unknown. we have investigated hsc66 substrate specificity using phage display and a peptide array of iscu. screening of a heptameric peptide phage display library revealed that hsc66 prefers peptides with a ce ...200211994302
salmonella and other enterobacteriaceae in dairy-cow feed ingredients: antimicrobial resistance in western oregon.several studies have suggested an association between the use of antimicrobial agents in animal feeds and an increased risk that humans will contract resistant strains of bacteria such as salmonella species, escherichia coli, and other enteric isolates. the authors of this study evaluated whether animal feeds might serve as sources of antimicrobial-resistant bacteria, especially bacteria that are pathogenic to humans. from july through august 1998, samples of feed ingredients were collected from ...200212004595
combination of pulsed-field gel electrophoresis (pfge) and single-enzyme amplified fragment length polymorphism (saflp) for differentiation of multiresistant salmonella enterica serotype typhimurium.to assess the combined application of plasmid profile typing, pulsed-field gel electrophoresis (pfge) and pcr-based single-enzyme amplified fragment length polymorphism (saflp) for the differentiation of 18 multiresistant (mr) and one drug-sensitive strain of salmonella enterica serotype typhimurium from humans and food animals.200212010170
[surveillance of escherichia coli o157:h7 among animals in jiangsu province in 1999].to understand the escherichia coli o157:h7 carrier rate of host animals and the toxic gene of the strains in different areas in jiangsu province.200212015089
efficacy of immunization with ferric citrate receptor feca from escherichia coli on induced coliform mastitis.the effects of immunization with the ferric citrate receptor feca on antibody responses and on experimentally induced mastitis following intramammary challenge were investigated. twenty-one cows were assigned to seven blocks of three cows based on expected parturition. cows within block were randomly assigned to one of three treatments: 1) feca immunization, 2) escherichia coli j5 immunization, and 3) unimmunized controls. challenge was by infusion of approximately 60 cfu of e. coli 727 into one ...200212018422
aggregation of animal lactobacilli with o157 enterohemorrhagic escherichia coli.the effect of selected autoaggregative lactobacilli on enterohemorragic o157 escherichia coli was studied. a total of 27 lactobacillus sp. strains were examined for expression of autoaggregation and cell surface hydrophobicity. autoaggregative isolates were obtained from the crops of chickens and vaginas of calves. aggregative activity was seen between eight autoaggregative lactobacilli and six strains of enterohemorrhagic e. coli o157. the presence of aggregation-promoting factor (apf gene) was ...200212019947
prevalence and molecular characterization of escherichia coli o157:h7 in bulk tank milk and fecal samples from cull cows: a 12-month survey of dairy farms in east tennessee.a study on the prevalence of escherichia coli o157:h7 was conducted on 30 dairy farms in east tennessee between may 2000 and april 2001. this pathogen was isolated from 8 of 30 (26.7%) dairy farms at various sampling times. a total of 415 fecal samples from cull dairy cows and 268 bulk tank milk samples were analyzed. overall, 10 of 683 (1.46%) samples (2 of 268 [0.75%] milk samples and 8 of 415 [1.93%] fecal samples) tested positive for e. coli o157:h7. food and drug administration bacteriologi ...200212030284
identification of escherichia coli o157:h7 and other enterohemorrhagic serotypes by ehec- hlya targeting, strand displacement amplification, and fluorescence polarization.human disease caused by enterohemorrhagic e. coli o157:h7 and other serotypes (ehec) has been associated with bovine fecal contamination of food and the environment. the range of serotypes, low infectious dose, and numerous transmission vehicles for ehec render development of detection methods for this pathogen complex. in this study, the hemolysin gene (ehec- hly a) was targeted with oligonucleotides, and probe-target hybrids were amplified using strand displacement amplification (sda). amplico ...200212030758
development of a procedure for discriminating among escherichia coli isolates from animal and human sources.counts of escherichia coli cells in water indicate the potential presence of pathogenic microbes of intestinal origin but give no indication of the sources of the microbial pollution. the objective of this research was to evaluate methods for differentiating e. coli isolates of livestock, wildlife, or human origin that might be used to predict the sources of fecal pollution of water. a collection of 319 e. coli isolates from the feces of cattle, poultry, swine, deer, goose, and moose, as well as ...200212039721
lochial secretions of escherichia coli- or arcanobacterium pyogenes-infected bovine uteri modulate the phenotype and the functional capacity of neutrophilic granulocytes.it has been suggested that in cases of puerperal endometritis of cattle infected with escherichia coli and arcanobacterium pyogenes, the neutrophils are compromised in their defense capacity or downregulated functionally. in addition to direct bacterial effects, contents of lochial secretions and secreted products of locally activated polymorphonuclear neutrophilic granulocytes (pmns) may also account for changes in function of freshly immigrating neutrophils. in this study, lochial secretions w ...200212041909
rapid selection of anti-hapten antibodies isolated from synthetic and semi-synthetic antibody phage display libraries expressed in escherichia coli.antibody phage display libraries (griffin and tomlinson i) displaying antibody genes and maintained and amplified in escherichia coli were used to isolate antibodies to the hapten target microcystin lr (1000 da) conjugated to either bovine serum albumin or keyhole limpet haemocyanin. in competition enzyme-linked immunosorbent assay, bacterially expressed antibodies selected via the griffin library showed at least 300 times greater sensitivity than those isolated from the tomlinson library, for f ...200212044684
ph, inhibitor, and substrate specificity studies on escherichia coli penicillin-binding protein 5.the recent structural determination of escherichia coli penicillin-binding protein 5 (pbp 5) provides the opportunity for detailed structure-function studies of this enzyme. pbp 5 was investigated in terms of its stability, linear reaction kinetics, acyl-donor substrate specificity, inhibition by a number of active site-directed reagents, and ph profile. pbp 5 demonstrated linear reaction kinetics for up to several hours. dilution of pbp 5 generally resulted in substantial loss of activity, unle ...200212044907
mycobacterium tuberculosis mammalian cell entry operon (mce) homologs in mycobacterium other than tuberculosis (mott).the cloned mammalian cell entry gene mce1a from mycobacterium tuberculosis confers to non-pathogenic escherichia coli the ability to invade and survive inside macrophages and hela cells. the aim of this work was to search for and characterize homologs of the four m. tuberculosis mammalian cell entry operons (mce1, mce2, mce3 and mce4) in mycobacteria other than tuberculosis (mott). the dot-blot and polymerase chain reaction (pcr) experiments performed on 24 clinical isolates representing 20 diff ...200212052567
effect of enrofloxacin treatment on plasma endotoxin during bovine escherichia coli mastitis.to investigate the effect of enrofloxacin on endotoxin resorption during bovine escherichia coli mastitis.200212058958
definition of the first mannosylation step in phosphatidylinositol mannoside synthesis. pima is essential for growth of mycobacteria.we examined the function of the pima (rv2610c) gene, located in the vicinity of the phosphatidylinositol synthase gene in the genomes of mycobacterium tuberculosis and mycobacterium smegmatis, which encodes a putative mannosyltransferase involved in the early steps of phosphatidylinositol mannoside synthesis. a cell-free assay was developed in which membranes from m. smegmatis overexpressing the pima gene incorporate mannose from gdp-[(14)c]man into di- and tri-acylated phosphatidylinositol mono ...200212068013
a new electron transport mechanism in mitochondrial steroid hydroxylase systems based on structural changes upon the reduction of adrenodoxin.the adrenal ferredoxin (adrenodoxin, adx) is an acidic 14.4-kda [2fe-2s] ferredoxin that belongs to the vertebrate ferredoxin family. it is involved in the electron transfer from the flavoenzyme nadph-adrenodoxin-reductase to cytochromes p-450(scc) and p-450(11)(beta). the interaction between the redox partners during electron transport has not yet been fully established. determining the tertiary structure of an electron-transfer protein may be very helpful in understanding the transport mechani ...200212069587
[survey of the presence of bacterial pathogens in foods sold at retail stores in the city of cassino].the presence of bacterial food pathogens was evaluated in 154 food samples collected from supermarkets and butchers in the city of cassino (south-central italy). food pathogens were identified in 17.5% of the total food samples. in the raw meat samples, 24.6% tested positives for listeria monocytogenes, 4.3% for salmonella and 2.9% for escherichia coli o157. y. enterocolitica, only investigated in pork meat, was identified in 7.4% of the samples. in poultry, l. monocytogenes was identified in 55 ...200212070904
fluorescently labelled bovine acyl-coa-binding protein acting as an acyl-coa sensor: interaction with coa and acyl-coa esters and its use in measuring free acyl-coa esters and non-esterified fatty acids.long-chain acyl-coa esters are key metabolites in lipid synthesis and beta-oxidation but, at the same time, are important regulators of intermediate metabolism, insulin secretion, vesicular trafficking and gene expression. key tools in studying the regulatory functions of acyl-coa esters are reliable methods for the determination of free acyl-coa concentrations. no such method is presently available. in the present study, we describe the synthesis of two acyl-coa sensors for measuring free acyl- ...200212071849
mucosal immunoadjuvant activity of the low toxic recombinant escherichia coli heat-labile enterotoxin produced by bacillus brevis for the bacterial subunit or component vaccine in pigs and cattle.a gene encoding the mature escherichia coli heat-labile enterotoxin (lt) lacking the nick site in the a subunit by deleting tripeptides was introduced in a vector pnh301 and expressed extracellularly as mutant molecule of holotoxin at high levels in bacilus brevis hpd31-s5 of the host bacterium. the mucosal adjuvant activities of the produced mutant lt (mlt) preparation were studied in pigs and cattle. intranasal immunization of pigs with the recombinant subunit vaccine of erysipelothrix rhusiop ...200212072249
the antimicrobial properties of milkfat after partial hydrolysis by calf pregastric lipase.studies on the kinetic characteristics of calf pregastric lipase (ec 3.1.1.3) have shown that it preferentially releases short chain fatty acids (scfas) from bovine milkfat. the released fatty acids form mixed micelle structures. the aim of this investigation has been to test whether hydrolysed milkfat is antimicrobial, and how the state of the emulsion alters the bactericidal or bacteriostatic effects. partial hydrolysis of milkfat by pregastric lipase was carried out in two types of emulsion s ...200212076524
effect of culture conditions on escherichia coli o157:h7-mediated attaching-effacing lesions in a bovine large intestinal mucosal explant model.the effects of culture conditions on the extent of escherichia coli o157:h7 attaching-effacing (a/e) adherence in an adult bovine large intestinal mucosal explant model were assessed by three different morphometric methods. measurement of the percent of tissue sections with a/e adherence and the number of foci of a/e adherence mm(-1) of surface epithelium was more sensitive than measurement of the percent of surface epithelium with a/e adherent bacteria for detection of treatment effects. cultur ...200212076795
production of recombinant buffalo (bubalus bubalis) and goat (capra hircus) growth hormones from genetically modified e. coli strains.the growth hormone cdnas of indian reverine buffalo (bubalus bubalis) and beetal goat (capra hircus) were cloned in escherichia coli through rt-pcr technique. nucleotide sequencing revealed several silent mutations in both cdnas and only one amino acid change in the case of goat when compared to reported bovine (bos taurus) sequence. the high level expression of both the polypeptide hormones was achieved in e. coli (> or =30% of soluble intracellular proteins) through the construction of two-cis ...200212084476
trends in antibacterial susceptibility of mastitis pathogens during a seven-year period.milk samples collected from dairy cattle suspected of having mastitis were submitted to the microbiology laboratory of the animal health diagnostic laboratory, michigan state university, for bacteriologic culture. a total of 2778 isolates, from the years 1994 to 2000, were isolated, identified, and subjected to in vitro antimicrobial susceptibility testing using the disk diffusion method, in accordance with national committee on clinical laboratory standards (nccls) standards. isolates included ...200212086045
the effect of pathogen-specific clinical mastitis on the lactation curve for somatic cell count.data from 274 dutch herds recording clinical mastitis (cm) over an 18-mo period were used to investigate the effect of pathogen-specific cm on the lactation curve for somatic cell count (scc). analyzed pathogens were staphylococcus aureus, coagulase-negative staphylococci, escherichia coli, streptococcus dysgalactiae, streptococcus uberis, other streptococci, and the culture-negative samples. the dataset contained 178,754 test-day records on scc, recorded in 26,411 lactations of 21,525 cows of d ...200212086069
acquisition of antibiotic resistance plasmids by enterohemorrhagic escherichia coli o157:h7 within rumen fluid.the emergence of antibiotic resistance among important foodborne pathogens like escherichia coli o157:h7 has become an important issue with regard to food safety. in contrast to the case for salmonella, antibiotic resistance has been slow in its development in e. coli o157:h7 despite the presence of mobile antibiotic resistance genes in other e. coli organisms that inhabit the same animal host. we set out to determine if rumen fluid influences the transfer of plasmid-mediated, antibiotic resista ...200212092718
wild animals as reservoirs of infectious diseases in the uk.this review aims to illustrate the extent to which wildlife act as reservoirs of infectious agents that cause disease in domestic stock, pet and captive animals and humans. more than 40 agents are described. in the case of some of these, e.g. cryptosporidium spp., escherichia coli o157 and malignant catarrhal fever, the current evidence is that wildlife either does not act as a reservoir or is of limited importance. however, in the case of many important diseases, including bovine tuberculosis, ...200212093188
structure-activity analysis of an antimicrobial peptide derived from bovine apolipoprotein a-ii.we previously showed that bovine apolipoprotein a-ii (apoa-ii) has antimicrobial activity against escherichia coli in pbs, and its c-terminal residues 49-76 are responsible for the activity using synthetic peptides. in order to understand the structural requirements of peptide 49-76 for the antimicrobial activity, the n- or c-terminus was truncated and then the charged (lys or asp) or ser residues were replaced by ala. deletion of the first or last three amino acids and replacement of lys-54/55 ...200212097167
development of an antibiotic resistance monitoring system in hungary.because of the rapid development and spread of antimicrobial resistance it is important that a system be established to monitor antimicrobial resistance in pathogenic zoonotic and commensal bacteria of animal origin. susceptibility testing of bacteria from carcasses and different samples of animal origin has been carried out in veterinary institutes for a long time but by an inconsistent methodology. the disc diffusion method proposed by the national committee for clinical laboratory standards ( ...200212113174
comparison between human and animal isolates of shiga toxin-producing escherichia coli o157 from australia.there is very little human disease associated with enterohaemorrhagic escherichia coli o157 in australia even though these organisms are present in the animal population. a group of australian isolates of e. coli o157:h7 and o157:h- from human and animal sources were tested for the presence of virulence markers and compared by xbai dna macrorestriction analysis using pulsed-field gel electrophoresis (pfge). each of 102 isolates tested contained the gene eae which encodes the e. coli attaching an ...200212113478
prevalence of and resistance to anti-microbial drugs in selected microbial species isolated from bulk milk samples.the prevalence of strains of staphylococcus aureus, coagulase-negative (cn) staphylococci, listeria monocytogenes, escherichia coli, enterococcus faecalis, e. faecium and bacillus cereus, was investigated in 111 bulk milk samples. staphylococcus aureus was isolated from 38 samples, cn staphylococci from 63 samples, e. coli from 49 samples, e. faecalis or e. faecium from 107 samples, and l. monocytogenes from two samples. bacillus cereus was not found in any of the samples and three samples were ...200212121041
occurrence and characterization of resistance to extended-spectrum cephalosporins mediated by beta-lactamase cmy-2 in salmonella isolated from food-producing animals in canada.resistance of salmonella to extended-spectrum cephalosporins (escs) is being reported with increasing frequency. in humans, infections with salmonella resistant to escs threaten the efficacy of ceftriaxone, the drug of choice for treating salmonellosis in children. to determine the occurrence of resistance to escs, we examined 8426 strains isolated from food-producing animals in canada in 1994-99 for reduced susceptibility or resistance to ceftriaxone. of the 8 such strains identified (7 from tu ...200212146884
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