Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| escherichia coli o157:h7 in livestock in japan. | the largest ever outbreak in japan of escherichia coli o157 infection in humans occurred in 1996. as a result, surveys were conducted later the same year to evaluate the sources and pathogenesis of this bacillus in livestock animals at the farm and in abattoirs. one of the surveys resulted in the isolation of e. coli o157 in 0.62% of cattle on randomly selected farms. although no confirmation has been made with regard to the source of e. coli o157 infection and its pathogenicity in livestock ani ... | 1997 | 9501352 |
| meat from dairy cows: possible microbiological hazards and risks. | the authors provide an overview of the circumstances associated with culling of dairy cattle in the united states of america (usa) and focus on the possible significant microbiological hazards associated with meat from cull dairy cows. cull dairy cows are an important source of food in the usa, accounting for at least approximately 17% of ground beef. the potential microbiological hazards for foodborne illness from cull dairy cows discussed here include salmonella (with special attention to s. t ... | 1997 | 9501354 |
| risks and prevention of contamination of dairy products. | consumers and regulatory officials are becoming increasingly aware of the human health risk of the presence of micro-organisms or chemicals in the agricultural environment. providing 'on-farm food safety' programmes which address the daily management of the production unit with regard to animal health and well-being, public health and environmental health must be a top priority for agriculturalists and veterinarians. developing critical control point management (ccpm) procedures for animal and h ... | 1997 | 9501360 |
| reduction of carriage of enterohemorrhagic escherichia coli o157:h7 in cattle by inoculation with probiotic bacteria. | bacteria inhibitory to escherichia coli o157:h7 were isolated from cattle and evaluated for their potential for reducing carriage of e. coli o157:h7 in calves. eighteen of 1,200 bacterial isolates from cattle feces and intestinal tissue samples were screened and determined to inhibit the growth of e. coli o157:h7 in vitro. seventeen of the isolates were e. coli and one was proteus mirabilis. none produced shiga toxin. genomic dna fingerprinting by pulsed-field gel electrophoresis revealed 13 dis ... | 1998 | 9508288 |
| oligosaccharide-derivatized dendrimers: defined multivalent inhibitors of the adherence of the cholera toxin b subunit and the heat labile enterotoxin of e. coli to gm1. | poly(propylene imine) dendrimers having four or eight primary amino groups and a starburst (pamam) dendrimer having eight primary amino groups were used as core molecules, to which phenylisothiocyanate derivatized (pitc) galbeta1-3galnacbeta1-4[sialic acid alpha2-3]-galbeta1-4glc (oligo-gm1) residues were covalently attached to yield multivalent oligosaccharides. the synthesis of the oligo-gm1-pitc derivatized dendrimers was monitored using high performance thin layer chromatography, infrared sp ... | 1997 | 9511989 |
| mechanisms of dna damage by chromium(v) carcinogens. | reactions of bis(2-ethyl-2-hydroxy-butanato)oxochromate(v) with puc19 dna, single-stranded calf thymus dna (ss-ctdna), a synthetic oligonucleotide, 5'-gatctatggacttacttcaaggccgggtaatgcta-3' (35mer), deoxyguanosine and guanine were carried out in bis-tris buffer at ph 7.0. the plasmid dna was only nicked, whereas the single-stranded dna suffered extensive damage due to oxidation of the ribose moiety. the primary oxidation product was characterized as 5-methylene-2-furanone. although all four base ... | 1998 | 9512527 |
| evaluation of an enzyme-linked immunosorbent assay using recombinant major surface protein 5 for serological diagnosis of bovine anaplasmosis in venezuela. | an indirect enzyme-linked immunosorbent assay (elisa) was developed for the serological diagnosis of bovine anaplasmosis with purified recombinant major surface protein 5 (msp5) of anaplasma marginale produced in escherichia coli. serum antibody responses against msp5 were detected in calves experimentally infected with a. marginale as early as 21 days postinfection and reached maximum titers at 28 days postinfection. the msp5 elisa performed with serum samples taken from field cattle from diffe ... | 1998 | 9521155 |
| one-headed kinesin derivatives move by a nonprocessive, low-duty ratio mechanism unlike that of two-headed kinesin. | a single molecule of the "two-headed" motor enzyme kinesin can move along a microtubule continuously for many enzymatic turnovers (processive movement), and the velocity produced by one kinesin molecule is the same as that produced by many kinesin molecules (high duty ratio). we studied the microtubule movement driven at 1 mm atp by biotinated n-terminal fragments of drosophila kinesin heavy chain attached to streptavidin-coated coverslips at various surface densities. k448-bio has velocity at a ... | 1998 | 9521668 |
| risk factors for clinical mastitis in a random sample of dairy herds from the southern part of the netherlands. | the incidence of clinical mastitis in dairy cows was estimated in 171 randomly selected dairy herds from the southern part of the netherlands. a total of 1103 quarter cases was reported. the mean annual incidence rate was 12.7 quarter cases/yr per 100 cows. the modeling incidence rate of clinical mastitis at the herd level indicated that a number of risk factors were associated with a higher rate of clinical mastitis: one or more cows that were leaking milk, one or more cows with trampled teats, ... | 1998 | 9532495 |
| alteration in immune responsiveness during the peripartum period and its ramification on dairy cow and calf health. | substantial evidence indicates that innate and acquired defense mechanisms are lowest from 3 wk precalving to 3 wk postcalving. this lowered responsiveness includes aspects of systemic and mammary gland immunity that may account, at least in part, for the increased incidence of peripartum disease. the physical and metabolic stresses of pregnancy, calving, and lactation may contribute to this decrease in host resistance and the subsequent increase in disease incidence. however, variation among co ... | 1998 | 9532513 |
| increased surface expression of cd11b receptors on polymorphonuclear leukocytes is not sufficient to sustain phagocytosis during escherichia coli mastitis in early postpartum dairy cows. | phagocytosis, cd11a and cd11b adhesion receptor expression, o2-production and maturity of circulating polymorphonuclear leukocytes (pmn) were studied during acute coliform mastitis in early postpartum dairy cows to obtain a better insight in the role of neutrophils in the pathology of this disease. the mammary gland of twelve newly calved high-yielding dairy cows was experimentally infected with escherichia coli. variability in clinical signs of mastitis and inhibition of milk production among c ... | 1997 | 9533266 |
| effects of growth hormone, insulin-like growth factor-i, and cortisol on periparturient antibody response profiles of dairy cattle. | the objectives of this study were to determine hormone and antibody response profiles from the prepartum period to peak lactation, and evaluate potential immunomodulatory effects of the classic endocrine hormones, growth hormone (gh), insulin-like growth factor-i (igf-i) and cortisol. specifically, 33 holstein cows were immunized with ovalbumin (ova) and escherichia coli j5 at weeks -8 and -3 prior to parturition. at parturition (week 0), cows received an additional immunization of ova. blood wa ... | 1997 | 9533267 |
| isolation and characterization of verocytotoxin-producing escherichia coli o157 strains from dutch cattle and sheep. | in the periods from july to november 1995 and 1996, fecal samples from dutch cattle and sheep were collected at the main slaughterhouses of the netherlands, located at different geographic sites. the samples were examined for the presence of verocytotoxin (vt)-producing escherichia coli (vtec) of serogroup 0157. e. coli o157 strains could be isolated from 57 (10.6%) of 540 adult cattle, 2 (0.5%) of 397 veal calves, 2 (3.8%) of 52 ewes, and 2 (4.1%) of 49 lambs. immunomagnetic separation with o15 ... | 1998 | 9542902 |
| a case-control study of verocytotoxigenic escherichia coli infection in cats with diarrhea. | the objectives of this study were to determine the prevalence of enteric verocytotoxigenic e. coli (vtec) infection in a population of cats in ontario, and to determine whether an association exists between the presence of vtec and feline diarrhea. fecal samples from 179 cats, representing 113 cats with diarrhea and 66 cats with normal feces, were cultured for e. coli. the fecal cultures were screened for verocytotoxin activity with a vero cell assay. confirmation of the presence of verocytotoxi ... | 1998 | 9553706 |
| phenotypic expression of k88 adhesion alone or simultaneously with k99 and/or f41 adhesins in the bovine enterotoxigenic escherichia coli strain b41. | f41-positive and f41-negative derivatives of bovine enterotoxigenic escherichia coli strain b41 carrying k88 or k88 and k99 plasmids were investigated for stability and expression of genes for their fimbrial antigens. either k88 plasmid alone or both k88 and k99 plasmids could be maintained in these strains though stability could depend on culture medium. k99 antigen could be detected in each strain bearing k99 plasmid. clones that produced k88 antigen or clones that did not produce this antigen ... | 1998 | 9556859 |
| nadph-flavodoxin reductase and flavodoxin from escherichia coli: characteristics as a soluble microsomal p450 reductase. | in addition to their endogenous roles as an activation system for various escherichia coli metabolic pathways, the soluble flavoproteins flavodoxin (fld) and nadph-flavodoxin (ferredoxin) reductase (fpr) can serve as an electron-transfer system for microsomal cytochrome p450s. furthermore, since fld and fpr are structurally similar to the functional domains (fmn binding and nadph/fad binding domains, respectively) of nadph-cytochrome p450 reductases (p450 reductases), these bacterial proteins re ... | 1998 | 9558349 |
| combined effect of ampicillin, colistin and dexamethasone administered intramuscularly to dairy cows on the clinico-pathological course of e. coli-endotoxin mastitis. | the effects of a single intramuscular injection of a drug product containing ampicillin, colistin and dexamethasone, as a suspension in a diester of propylene glycol of medium-chain fatty acids, on the clinico-pathological course of experimental escherichia coli-endotoxin mastitis was examined in 30 dairy cows. cows were divided into five groups, six cows per group, and 24 of them were infused with e. coli endotoxin into two quarters of their udders. the drug product was injected at 25,000 iu co ... | 1998 | 9559523 |
| type specific and genotype cross reactive b epitopes of the l1 protein of hpv16 defined by a panel of monoclonal antibodies. | mouse monoclonal antibodies (mabs) were raised against the major capsid protein, l1, of human papillomavirus type 16 (hpv16), produced in escherichia coli with the expression plasmid ptrcl1. epitope specificity could be assigned to 11 of these 12 antibodies using a series of linear peptides and fusion proteins from hpv16. one mab (mc53) recognized a novel linear epitope that appears to be unique to the hpv16 genotype. a further 11 mabs were characterized as recognizing novel and previously defin ... | 1998 | 9568027 |
| crystallization and preliminary x-ray analysis of a 1:1 complex between a designed monomeric interferon-gamma and its soluble receptor. | a variant of human interferon-gamma (ifn-gamma) has been created in which the two chains of the homodimeric cytokine were linked n- to c-terminus by an eight residue polypeptide linker. the sequence of this linker was derived from a loop in bira bifunctional protein, and was determined from a structural database search. this "single-chain" variant was used to create an ifn-gamma molecule that binds only a single copy of the alpha-chain receptor, rather than the 2 alpha-chain receptor: 1 ifn-gamm ... | 1998 | 9568913 |
| cattle and verotoxigenic escherichia coli (vtec), an old relationship? | 1998 | 9569484 | |
| effects of temperature and novobiocin on the expression of calf prochymosin gene and on plasmid copy number in recombinant escherichia coli. | escherichia coli strain hb101 harboring an expression plasmid bearing calf prochymosin gene under the control of the tac promoter was grown in the presence of iptg with or without novobiocin at 28 and 40 degrees c, respectively. the differential rates of synthesis of prochymosin inclusions, and, for comparison, of beta-lactamase and beta-galactosidase, as well as plasmid copy number, were determined during the first hours of steady state growth. at 28 degrees c the induced expression of prochymo ... | 1998 | 9569630 |
| delta subunit of rat liver mitochondrial atp synthase: molecular description and novel insights into the nature of its association with the f1-moiety. | the f1 moiety of atp synthase complexes consists of five subunit types in the stoichiometric ratio alpha 3, beta 3, gamma, delta epsilon. of these, the delta subunit has received very little attention in the study of f1 preparations from eukaryotic cells. although recently shown to associate tightly with the beta subunit [pedersen, p. l., hullihen, j., bianchet, m., amzel, l. m., and lebowitz, m. s. (1995) j. biol. chem. 270, 1775-1784], the delta subunit is not resolved in the x-ray structure o ... | 1998 | 9578578 |
| expression of catalytically active human cytochrome p450scc in escherichia coli and mutagenesis of isoleucine-462. | cytochrome p450scc (p450scc) catalyzes the first step in steroid hormone synthesis, the conversion of cholesterol to pregnenolone. human p450scc has been poorly studied due to the difficulty of purifying reasonable quantities of enzyme from human tissue. to provide a more convenient source of the human enzyme and to enable structure-function studies to be done using site-directed mutagenesis, we expressed the mature form of human p450scc in escherichia coli. the expression system enabled us to p ... | 1998 | 9578606 |
| endotoxin impairs agonist-induced calcium mobilization in bovine aortic myocytes by a nitric oxide-independent mechanism. | we hypothesized that endotoxin (lps) would impair vasoconstrictor-agonist-induced calcium (ca2+) mobilization by a nitric oxide (no)-dependent mechanism. we incubated bovine aortic myocytes (passages 16 to 23) for 22 to 24 hours with 0 to 1.0 mg/ml escherichia coli lipopolysaccharide (lps). medium (dulbecco's modified eagle's medium (dmem) + 10% fetal bovine serum (fbs)) was assayed for nitrite (chemiluminescence), and myocytes were loaded with fura-2 acetoxymethyl ester (fura-2am), after which ... | 1998 | 9579387 |
| mitochondrial methionyl-trna transformylase from bovine liver. | substrate specificities of mammalian mitochondrial methionyl-trna transformylase (mtfmt) toward trna substrates were characterized in vitro. the mtfmt is able to formylate e. coli initiator methionyl-trna (met-trna(fmet)) as efficiently as mammalian mitochondrial methionyl-trna. furthermore, e. coli elongator methionyl-trna (met-trna(mmet)) also serves as a substrate for mt mtf, whereas e. coli mtf rigorously excludes e. coli met-trna(mmet) from formylation reaction. thus, mammal mt mtf is sugge ... | 1997 | 9586066 |
| studies of the presence of verocytotoxic escherichia coli o157 in bovine faeces submitted for diagnostic purposes in england and wales and on beef carcases in abattoirs in the united kingdom. | a survey of beef carcases in abattoirs in the uk was carried out in order to estimate the prevalence of contamination with verocytotoxin-producing escherichia coli (vtec) serogroup o157. contamination with verocytotoxin-producing e. coli (vtec) o157 was confirmed in 0.47% of the 4067 (95% confidence limits 0.22-1.00%) of neck muscle samples. a significant tendency for carcases present in the same abattoir on the same day to have similar results was found, thus suggesting cross contamination. vte ... | 1998 | 9593489 |
| the occurrence and replication of escherichia coli in cattle feeds. | sixty-three of 209 (30.1%) samples of cattle feed that were collected from multiple commercial sources and from farms were found to contain escherichia coli. however, none of the feed samples examined were culture-positive for e. coli o157. replication of fecal e. coli, including e. coli o157, was demonstrated in a variety of feeds at temperatures that were similar to those found on farms in summer months. fresh mixed rations containing corn silage were sampled from 16 dairies. rations from 12 o ... | 1998 | 9594399 |
| on-line dual microdialysis with esi-ms for direct analysis of complex biological samples and microorganism lysates. | a novel dual-microdialysis approach has been developed for fast and efficient fractionation and cleanup for esi-ms and esi ms/ms analyses of biological samples. a modified dynamic microdialyzer utilizing two mirror-image serpentine channels, which sandwich a regenerated cellulose membrane of selected molecular weight cutoff, serves as the first stage for the removal of high-molecular-weight components and cellular residue. the second stage employs a hollow microdialysis capillary to remove low-m ... | 1998 | 9599580 |
| [acute diarrhea: stool water loss in hospitalized infants and its correlation with etiologic agents and lactose content in the diet]. | forty weaned male infants were studied during their first year of life, all hospitalized with acute diarrhea in the gastroenterology and metabolism unit of the hospital "umberto i", são paulo, sp, brazil. we evaluated and quantified water fecal losses, employing the metabolic bed technique, relating the feeding formula employed with the different causal enteropathogenic agents. 67.5% of the studied infants were under six months and 40% under three months of age. two groups were randomly assemble ... | 1997 | 9611297 |
| mammalian mitochondrial methionyl-trna transformylase from bovine liver. purification, characterization, and gene structure. | the mammalian mitochondrial methionyl-trna transformylase (mtfmt) was partially purified 2,200-fold from bovine liver mitochondria using column chromatography. the polypeptide responsible for mtfmt activity was excised from a sodium dodecyl sulfate-polyacrylamide gel and the amino acid sequences of several peptides were determined. the cdna encoding bovine mtfmt was obtained and its nucleotide sequence was determined. the deduced amino acid sequence of the mature form of mtfmt consists of 357 am ... | 1998 | 9614118 |
| lipofection of cultured mouse muscle cells: a direct comparison of lipofectamine and dosper. | cationic lipid-dna complexes (lipoplexes) have been widely used as gene transfer vectors which avoid the adverse immunogenicity and potential for viraemia of viral vectors. with the long-term aim of gene transfer into skeletal muscle in vivo, we describe a direct in vitro comparison of two commercially available cationic lipid formulations, lipofectamine and dosper. optimisation of transfection was performed in the c2c12 mouse muscle cell line, before further studies in primary mouse myoblasts a ... | 1998 | 9614580 |
| the flavoprotein component of the escherichia coli sulfite reductase can act as a cytochrome p450c17 reductase. | the flavoprotein component (sir-fp) of the e. coli sulfite reductase was found to support 17 alpha-hydroxylation of pregnenolone in the presence of cytochrome p450c17. half maximum activity is obtained for a 1:1 ratio of sir-fp, expressed as monomer concentration, to p450c17. when compared to bovine nadph-cytochrome p450 reductase, sir-fp is about 12-15 times less efficient. p450c17 was demonstrated to interact specifically with the fmn-binding domain of the protein and the n-terminal part of si ... | 1998 | 9618257 |
| the dinuclear center of cytochrome bo3 from escherichia coli. | for the study of the dinuclear center of heme-copper oxidases cytochrome bo3 from escherichia coli offers several advantages over the extensively characterized bovine cytochrome c oxidase. the availability of strains with enhanced levels of expression allows purification of the significant amounts of enzyme required for detailed spectroscopic studies. cytochrome bo3 is readily prepared as the fast form, with a homogeneous dinuclear center which gives rise to characteristic broad epr signals not ... | 1998 | 9623806 |
| association of genes encoding p fimbriae, cs31a antigen and east 1 toxin among cnf1-producing escherichia coli strains from cattle with septicemia and diarrhea. | fifty-six cnf1-producing escherichia coli strains isolated from cattle with diarrhea or septicemia were screened by pcr for the detection of pap, sfa, afa, clpg, or f17 adherence factor and east 1 toxin genes. all the isolates were pap-positive, in accordance with the close association of pap, cnf1 and alpha-hemolysin genes observed on human and porcine e. coli. only the gene encoding the p adhesin of class iii (prsg) was detected. genes encoding cs31a antigen (71%) and s fimbriae (34%) (but not ... | 1998 | 9627958 |
| research notes: prevalence of selected microbial pathogens in processed poultry waste used as dairy cattle feed. | processed poultry litter intended for dairy cattle feed was collected on 13 dairy ranches in the san joaquin valley of california and analyzed for the presence of significant bacterial pathogens associated with clinical disease in cattle or foodborne disease in humans. litter samples were collected from the surface and interior of the litter piles upon arrival on the dairies and 2 to 4 wk later. litter samples were cultured for salmonella, escherichia coli, campylobacter, and other bacteria. the ... | 1998 | 9628527 |
| adhesion of some probiotic and dairy lactobacillus strains to caco-2 cell cultures. | the adhesion of 12 different lactobacillus strains was studied using caco-2 cell line as an in vitro model for intestinal epithelium. some of the strains tested have been used as probiotics, and most of them are used in the dairy and food industry. human and bovine enterotoxigenic escherichia coli strains were used as positive and negative control, respectively. bacterial adhesion to caco-2 cell cultures was quantitated using radiolabelled bacteria. the adherence of bacteria was also observed mi ... | 1998 | 9631336 |
| novel recombinant analogues of bovine placental lactogen. g133k and g133r provide a tool to understand the difference between the action of prolactin and growth hormone receptors. | two new analogues of bovine placental lactogen (bpl), bpl(g133k) and bpl(g133r), were expressed in escherichia coli, refolded, and purified to a native form. binding experiments, which are likely to represent the binding to site 1 only, to intact fdc-p1 cells transfected with rabbit (rb) growth hormone receptor (ghr) or with human (h) ghr, to nb2 rat lymphoma cells, or to rabbit mammary gland membranes prolactin receptor (prlr), revealed only small or no reduction in binding capacity. the comple ... | 1998 | 9632658 |
| factors affecting the heat resistance of escherichia coli o157:h7. | escherichia coli o157:h7 has been reported as being not particularly heat resistant. however, several factors which might increase its heat resistance have been investigated in this study using five strains. increase in growth temperature to 40 degrees c, as found in the cow gut, heat-shock at sub-lethal temperatures of 42, 45, 48 and 50 degrees c, and variable heating rate (1 degree c min-1 to 23 degrees c min-1) had no dramatic effect on heat resistance. growth phase had a marked impact on hea ... | 1998 | 9633099 |
| compensation of preliminary blood phagocyte immaturity in the newborn calf. | to estimate the functional maturity of the phagocytic defence in neonatal calves, we analyzed the characteristics of blood phagocytes from calves (n = 10) 1 h post partum (p.p.) and 4 h p.p. at 1 h p.p., all calves were colostrum-deprived, while 5 calves had received colostrum before the 4 h p.p. sampling. the results were compared to those obtained from 3-9-week-old calves (n = 10). phagocytic and oxidative burst activity of polymorphonuclear leukocytes (pmnl) and monocytes were determined in w ... | 1998 | 9646436 |
| endocytosis and mhc class ii expression by human oviductal epithelium according to stage of the menstrual cycle. | the epithelium is the first barrier against pathogens invading the lumen of the human oviduct. its expression of class ii major histocompatibility complex (mhc class ii) proteins suggests that it might play a role in antigen presentation during the local immune response. to study the role of the oviductal epithelium in antigen processing, its endocytic properties and mhc class ii expression were examined. for assay of endocytosis, fluorescein isothiocyanate-labelled bovine serum albumin (bsa-fit ... | 1998 | 9647540 |
| potent enzyme inhibitors derived from dromedary heavy-chain antibodies. | evidence is provided that dromedary heavy-chain antibodies, in vivo-matured in the absence of light chains, are a unique source of inhibitory antibodies. after immunization of a dromedary with bovine erythrocyte carbonic anhydrase and porcine pancreatic alpha-amylase, it was demonstrated that a considerable amount of heavy-chain antibodies, acting as true competitive inhibitors, circulate in the bloodstream. in contrast, the conventional antibodies apparently do not interact with the enzyme's ac ... | 1998 | 9649422 |
| detection of verotoxin-producing escherichia coli o157:h7 by multiplex polymerase chain reaction. | we constructed primers for multiplex polymerase chain reaction (pcr) to detect verotoxin-producing escherichia coli (vtec) o157:h7. the multiplex pcr primers were designed from the sequence of the flagellin structural gene of escherichia coli flagellar type h7 (genbank under accession number l07388), and from the sequence of the rfbe gene of escherichia coli o157:h7 (genbank under accession number s83460). in addition to these primers, we used a primer pair reported by karch and meyer (j. clin. ... | 1998 | 9654369 |
| u1 snrnp inhibits pre-mrna polyadenylation through a direct interaction between u1 70k and poly(a) polymerase. | it has previously been shown in vivo that bovine papillomavirus represses its late gene expression via a 5' splice site sequence located upstream of the late polyadenylation signal. here, the mechanism of repression is determined by in vitro analysis. u1 snrnp binding to the 5' splice site results in inhibition of polyadenylation via a direct interaction with poly(a) polymerase (pap). although the inhibitory mechanism is similar to that used in u1a autoregulation, u1a within the u1 snrnp does no ... | 1998 | 9659922 |
| virulence determinants of escherichia coli isolated from milk of sows with coliform mastitis. | escherichia coli isolates recovered from the milk of sows with coliform mastitis were examined to determine their biochemical and serologic characteristics, serum resistance and ability to adhere to fibronectin and bovine fetal fibroblasts. no common biotype was identified, and a variety of serovars were detected. ninety-five per cent of the investigated strains were serum resistant in swine serum. binding to fibronectin was demonstrated in most of the strains. at a binding level above 13% of th ... | 1998 | 9673580 |
| differentiation and quantification of theileria sergenti piroplasm types using type-specific monoclonal antibodies. | antigenic properties of two representative allelic products of the major piroplasm surface protein (mpsp) of theileria sergenti were studied. sera from cattle infected with either of ikeda and chitose types of the parasite reacted strongly with homologous but weakly with heterologous recombinant antigens in immunoblotting. monoclonal antibodies (moabs) produced against the both allelic products of mpsp parasites reacted only to the immunizing antigen. these results suggested that crossreactivity ... | 1998 | 9673935 |
| association of herd management factors with colonization of dairy cattle by shiga toxin-positive escherichia coli o157. | management factors in 36 pacific northwest dairy herds were evaluated for their association with the prevalence of shiga toxin-positive escherichia coli o157 (e. coli o157) in dairy cattle. the within-herd prevalence of e. coli o157 was estimated by bacteriological culture of fecal pat samples, collected monthly for 6 months (approximately 60 per visit), from heifer cattle. during the first visit to each farm, a management questionnaire was administered that covered a broad range of animal husba ... | 1998 | 9678159 |
| enhancement by copper, zinc superoxide dismutase of dna damage and mutagenicity with hydrogen peroxide. | oxidative dna damage caused by hydrogen peroxide was enhanced by copper, zinc superoxide dismutase (cuznsod) in a concentration-dependent manner, as reflected by the formation of 8-hydroxy-2'-deoxyguanosine (8-oh-dg) and strand breaks. hydroxyl radical scavengers such as sodium azide, mannitol and 5,5-dimethyl-1-pyrroline n-oxide (dmpo), a metal chelator, diethylenetriamine-pentaacetic acid, and catalase decreased strand breaks and 8-oh-dg formation in dna. the deoxyribose assay showed that hydr ... | 1998 | 9679665 |
| the region of alpha-lactalbumin recognized by groel. | the binding constants between disulfide-intact or various disulfide-reduced bovine alpha-lactalbumins and an escherichia coli chaperonin, groel, were determined by using the equilibrium dialysis method. the disulfide-intact and one-disulfide (cys6-cys120)-reduced alpha-lactalbumins were shown not to bind with groel both in the presence and absence of ca2+. the two-disulfide (cys6-cys120 and cys28-cys111)-reduced alpha-lactalbumin, which has the native-like tertiary structure in its beta-domain r ... | 1998 | 9685721 |
| role of phe120 in the activity and structure of bovine pancreatic ribonuclease a. | phenylalanine120 is a candidate residue juxtaposing catalytic his12 and his119 in ribonuclease a (rnase a). to clarify its role in construction of the catalytic center, phe120 was replaced by alanine, tryptophan, leucine, or glutamic acid by site-directed mutagenesis. the transphosphorylation and hydrolysis activities of the mutant rnase as, respectively, toward cytidinyl 3',5' adenosine (cpa) and cytidine 2',3' cyclic monophosphate (c>p) were compared with those of the wild type enzyme. the km ... | 1998 | 9685734 |
| expression and equilibrium denaturation of cardiac troponin i: stabilization of a folding intermediate during denaturation by urea. | human cardiac troponin i has been expressed at high level in escherichia coli as a fusion protein by using the expression vector ptac114. the expressed protein forms primarily intracellular inclusion bodies that are solubilized in the presence of 8 m urea. the purified troponin i is recognized by anti-(human cardiac troponin i) monoclonal antibodies. equilibrium denaturation of recombinant human troponin i and bovine troponin i is compared by monitoring changes in the protein's fluorescence and ... | 1998 | 9693083 |
| actin enhances the haemolytic activity of escherichia coli. | actin is a major cytoskeletal protein of mammalian muscle and non-muscle cells. exposure of cells to soluble factors that damage cell membranes results in the release of actin into the extracellular spaces. the alpha-haemolysin (hlya) of escherichia coli is the prototype rtx (repeat in toxin) toxin and is thought to be important in virulence because of its ability to lyse cells by formation of pores in the cell membrane. these studies were conducted to determine if actin influences growth and ha ... | 1998 | 9695917 |
| influence of escherichia coli endotoxin induced fever on the pharmacokinetics and dosage regimen of oxytetracycline in cross-bred calves. | the pharmacokinetics and dosage regimen of oxytetracycline were determined in healthy and febrile cross-bred calves following its single intravenous administration (10 mg kg-1). fever was induced by a single intravenous injection of e. coli endotoxin (1 microgram kg-1 i.v.). the elimination half-life (t1/2 beta) and the apparent volume of distribution [vd(area)] were slightly increased in febrile calves, as compared to healthy animals. the values of t1/2 beta and vd(area) were 3.22 +/- 0.20 h an ... | 1998 | 9704514 |
| use of hot water for beef carcass decontamination. | hot water treatment of beef carcass surfaces for reduction of escherichia coli o157:h7, salmonella typhimurium, and various indicator organisms was studied using a model carcass spray cabinet. paired hot carcass surface regions with different external fat characteristics (inside round, outside round, brisket, flank, and clod) were removed from carcasses immediately after the slaughter and dressing process. all cuts were inoculated with bovine feces containing 10(6)/g each of rifampicin-resistant ... | 1998 | 9708247 |
| a representative microbial sampling method for large commercial containers of raw beef based on purge. | the purge from beef combos ( a boxed collection of beef trimmings) was tested as a means of representatively sampling the microbial content of this raw product. in the first experiment, purge was sampled from model beef combos that had been inoculated with bovine feces.. data from this experiment indicated a strong correlation (r = 0.94) between the total aerobic bacteria counts derived from the purge samples of a model beef combo and the total aerobic bacteria present in a rinse sample of the e ... | 1998 | 9708274 |
| thermal inactivation of escherichia coli o157:h7 isolated from ground beef and bovine feces, and suitability of media for enumeration. | rates of thermal inactivation of five strains of escherichia coli o157:h7 isolated from ground beef implicated in outbreaks of hemorrhagic colitis and five strains isolated from bovine feces were determined. ground beef (22% fat, 10 g), inoculated with individual test strains at populations ranging from 6.85 to 7.40 log10 cfu g-1 of beef, was formed into patties (0.3 cm thick and 8.0 cm in diameter) and sealed in polyethylene bags. for each strain and treatment temperature (54.4, 58.9, 62.8, 65. ... | 1998 | 9708297 |
| long-term effect of alkaline, organic acid, or hot water washes on the microbial profile of refrigerated beef contaminated with bacterial pathogens after washing. | the effect of 2% (vol/vol) lactic acid, 2% (vol/vol) acetic acid, 12% (wt/vol) trisodium phosphate, water at 72 degrees c and water at 32 degrees c washes on bacterial populations introduced onto beef carcass surfaces after treatment was determined for up to 21 days at 4 degrees c storage in vacuum packaging. beef carcass short plates were collected from cattle immediately after slaughter and subjected to the above treatments or left untreated (c). short plates were then inoculated with low leve ... | 1998 | 9708300 |
| an efficient sampling technique used to detect four foodborne pathogens on pork and beef carcasses in nine belgian abattoirs. | the method presented in this paper should prove useful in assessing the effectiveness of haccp plans developed in slaughterhouses. samples were collected by swabbing well-defined areas of pork and beef carcasses with sterile gauze. between 160 and 420 half-carcasses were swabbed in each of nine pork or beef slaughterhouses. swabs from five carcasses were placed in the same sterile stomacher bag, constituting a single composite sample. standard or validated analytical methods were used to isolate ... | 1998 | 9709223 |
| steam pasteurization of commercially slaughtered beef carcasses: evaluation of bacterial populations at five anatomical locations. | a steam pasteurization process (patent pending) has been shown to effectively reduce pathogenic bacterial populations on beef tissue and to significantly reduce naturally occurring bacterial populations on commercially slaughtered beef carcasses. the objective of this study was to determine the effectiveness of the steam pasteurization treatment for reducing bacterial populations at several anatomical locations on commerically slaughtered carcasses. before and after pasteurization treatment (82. ... | 1998 | 9709229 |
| mutagenicity of p-aminophenol in e. coli wp2uvra/pkm101 and its relevance to oxidative dna damage. | it was recently reported that p-aminophenol (p-ap) induces dna cleavage in mouse lymphoma cells, cho cells and human lymphoblastoid cells. the mutagenicity of p-ap has not, however, been detected by reverse mutation assays. the purpose of this study was to assess the mutagenicity of p-ap by reverse mutation assay using escherichia coli wp2uvra/pkm101, which has a spectrum for detecting mutations different from those of other strains in the family with an at base pair at the mutation site and has ... | 1998 | 9711270 |
| bovine herpesvirus type 1 glycoprotein h is essential for penetration and propagation in cell culture. | bovine herpesvirus type 1 (bhv-1) glycoprotein h (gh) is a structural component of the virion which forms a complex with glycoprotein gl. to study the role of bhv-1 gh in the virus infectious cycle, a gh null mutant was constructed in which the gh coding sequences were deleted and replaced by the escherichia coli lacz cassette. the bhv-1 gh null mutant was propagated in trans-complementing mdbk cells, stably transfected with plasmid pmep4 containing the bhv-1 gh gene under the control of the ind ... | 1998 | 9714247 |
| surveillance of antimicrobial resistance in bacteria isolated from food animals to antimicrobial growth promoters and related therapeutic agents in denmark. | this study was conducted to describe the occurrence of acquired resistance to antimicrobials used for growth promotion among bacteria isolated from swine, cattle and poultry in denmark. resistance to structurally related therapeutic agents was also examined. three categories of bacteria were tested: 1) indicator bacteria (escherichia coli, enterococcus faecalis, enterococcus faecium), 2) zoonotic bacteria (campylobacter, salmonella, yersinia enterocolitica), and 3) animal pathogens (e. coli, sta ... | 1998 | 9725794 |
| analysis of escherichia coli o157:h7 survival in ovine or bovine manure and manure slurry. | farm animal manure or manure slurry may disseminate, transmit, or propagate escherichia coli o157:h7. in this study, the survival and growth of e. coli o157:h7 in ovine or bovine feces under various experimental and environmental conditions were determined. a manure pile collected from experimentally inoculated sheep was incubated outside under fluctuating environmental conditions. e. coli o157:h7 survived in the manure for 21 months, and the concentrations of bacteria recovered ranged from <10( ... | 1998 | 9726855 |
| pcr-based dna amplification and presumptive detection of escherichia coli o157:h7 with an internal fluorogenic probe and the 5' nuclease (taqman) assay. | presumptive identification of escherichia coli o157:h7 is possible in an individual, nonmultiplexed pcr if the reaction targets the enterohemorrhagic e. coli (ehec) eaea gene. in this report, we describe the development and evaluation of the sensitivity and specificity of a pcr-based 5' nuclease assay for presumptively detecting e. coli o157:h7 dna. the specificity of the eaea-based 5' nuclease assay system was sufficient to correctly identify all e. coli o157:h7 strains evaluated, mirroring the ... | 1998 | 9726887 |
| structural and functional consequences of substitutions at the pro108-arg14 hydrogen bond in bovine adrenodoxin. | elimination of pro108 in bovine adrenodoxin is known to result in the formation of a misfolded protein that is not able to incorporate a [2fe-2s] cluster and rapidly degrades upon expression in e. coli. however, no experimental explanation for this phenomenon has been demonstrated so far. using the recently obtained 3d structure of the truncated mutant adx(4-108) we have studied the reasons of the protein stabilization by the proline residue by means of site-directed muta-genesis. two main resul ... | 1998 | 9731239 |
| grain feeding and the dissemination of acid-resistant escherichia coli from cattle. | the gastric stomach of humans is a barrier to food-borne pathogens, but escherichia coli can survive at ph 2.0 if it is grown under mildly acidic conditions. cattle are a natural reservoir for pathogenic e. coli, and cattle fed mostly grain had lower colonic ph and more acid-resistant e. coli than cattle fed only hay. on the basis of numbers and survival after acid shock, cattle that were fed grain had 10(6)-fold more acid-resistant e. coli than cattle fed hay, but a brief period of hay feeding ... | 1998 | 9733511 |
| rna polymerase ii is an essential mrna polyadenylation factor. | production of messenger rna in eukaryotic cells is a complex, multistep process. mrna polyadenylation, or 3' processing, requires several protein factors, including cleavage/polyadenylation-specificity factor (cpsf), cleavage-stimulation factor, two cleavage factors and poly(a) polymerase. these proteins seem to be unnecessary for other steps in mrna synthesis such as transcription and splicing, and factors required for these processes were not considered to be essential for polyadenylation. non ... | 1998 | 9738505 |
| immunization of cows with ferric enterobactin receptor from coliform bacteria. | the serum and milk immunoglobulin (ig) g responses of lactating dairy cows were determined following immunization with ferric enterobactin receptor fepa. escherichia coli 471 was cultured in iron-depleted medium, and outer membrane proteins were extracted by 2% n-lauroylsarcosine sodium salt and 2% triton x-100. the fepa was isolated from the outer membrane proteins by ion-exchange chromatography. twenty cows were assigned to four treatment groups of 5 cows blocked by breed and days in milk. tre ... | 1998 | 9749380 |
| partial budget of the discounted annual benefit of mastitis control strategies. | the objective of this study was to rank the benefits associated with various mastitis control strategies in simulated herds with intramammary infections caused by streptococcus agalactiae, streptococcus spp. other than strep. agalactiae, staphylococcus aureus, coagulase-negative staphylococci, and escherichia coli. the control strategies tested were prevention, vaccination for e. coli, lactation therapy, and dry cow antibiotic therapy. partial budgets were based on changes caused by mastitis con ... | 1998 | 9749395 |
| are all infections with escherichia coli o157 associated with cattle? | 1998 | 9759740 | |
| nucleoside diphosphate kinase from bovine retina: purification, subcellular localization, molecular cloning, and three-dimensional structure. | the biochemical and structural properties of bovine retinal nucleoside diphosphate kinase were investigated. the enzyme showed two polypeptides of approximately 17.5 and 18.5 kda on sds-page, while isoelectric focusing revealed seven to eight proteins with a pi range of 7.4-8.2. sedimentation equilibrium yielded a molecular mass of 96 +/- 2 kda for the enzyme. carbohydrate analysis revealed that both polypeptides contained gal, man, glcnac, fuc, and galnac saccharides. like other nucleoside diph ... | 1998 | 9760230 |
| recombinant jembrana disease virus proteins as antigens for the detection of antibody to bovine lentiviruses. | jembrana disease virus (jdv) is a recently identified bovine lentivirus causing an acute severe disease syndrome in banteng cattle (bos javanicus) and a milder disease syndrome in bos taurus cattle in indonesia. the virus is closely related genetically to the previously identified bovine lentivirus, bovine immunodeficiency virus (biv). recombinant clones were produced which contained the capsid (ca) and transmembrane (tm) subunits of the respective gag and env open reading frames of jdv. the pro ... | 1998 | 9763127 |
| an improved direct plate method for the enumeration of stressed escherichia coli o157:h7 from food. | the use of sorbitol macconkey agar (smac) performed poorly in supporting growth of stressed escherichia coli o157:h7 cells. up to a 3-log difference was observed between counts on smac and tryptone soy agar (tsa). it is critical in the risk assessment of certain foods to be able to enumerate stressed and healthy e. coli o157:h7 in a background of potentially healthy competing bacteria. investigations carried out to overcome the inhibitory effect of smac included the reduction of the selective ag ... | 1998 | 9766057 |
| bacterial profile of ground beef made from carcass tissue experimentally contaminated with pathogenic and spoilage bacteria before being washed with hot water, alkaline solution, or organic acid and then stored at 4 or 12 degrees c. | the long-term effectiveness of several beef-carcass surface-tissue (bct) wash interventions on the microbiology of ground beef produced from this tissue was determined. bct was inoculated with bovine feces containing one of two different levels (ca. 4 or 6 log cfu/ml) of escherichia coli o157:h7, listeria innocua, salmonella typhimurium, and clostridium sporogenes. the bct was then subjected to one of several treatment washes: 2% (vol/vol) dl-lactic acid (la), 2% (vol/vol) acetic acid (aa), 12% ... | 1998 | 9766060 |
| detection of heavy metal ions at femtomolar levels using protein-based biosensors. | sensors based on proteins (gst-smta and merr) with distinct binding sites for heavy metal ions were developed and characterized. a capacitive signal transducer was used to measure the conformational change following binding. the proteins were overexpressed in escherichia coli, purified, and immobilized in different ways to a self-assembled thiol layer on a gold electrode placed as the working electrode in a potentiostatic arrangement in a flow analysis system. the selectivity and the sensitivity ... | 1998 | 9784752 |
| biological characterization of a novel mammalian antimicrobial peptide. | a putative antimicrobial peptide of 34 residues was recently deduced from a bovine cathelicidin gene sequence and named bmap-34. a peptide based on the deduced sequence was chemically synthesized and used to study the localization, structure and biological activities of bmap-34. a western blot analysis using antibodies raised to the synthetic peptide showed that bmap-34 is stored as proform in the cytoplasmic granules of bovine neutrophils. cd spectroscopy indicates that the peptide assumes an a ... | 1998 | 9795251 |
| cyp12a1, a mitochondrial cytochrome p450 from the house fly. | eukaryotic p450 proteins are membrane proteins found predominantly in the endoplasmic reticulum. in vertebrates, several biosynthetic p450s are found in mitochondria as well. we cloned three putative insect mitochondrial p450s from larval house fly cdna. these p450s are members of a new p450 family, cyp12. the cyp12 proteins are most closely related to the mammalian mitochondrial p450 of the cyp11, cyp24, and cyp27 families. the most abundant cdna, cyp12a1, was expressed in escherichia coli and ... | 1998 | 9808765 |
| expression and characterization of bovine mitochondrial methionyl-trna transformylase. | translational initiation in bacteria and some organelles such as mitochondria and chloroplasts requires formyl-methionyl-trna (fmet-trna). methionyl-trna (met-trna) undergoes formylation by methionyl-trna transformylase (mtf), and the resulting fmet-trna is utilized exclusively in the initiation process. the gene encoding mammalian mitochondrial mtf (mtfmt) was cloned recently. when the cdna corresponding to mature mtfmt was cloned into an expression vector, no expression of mtfmt was observed. ... | 1998 | 9832609 |
| characterisation of escherichia coli o157:h7 (h-) derived from cattle using random amplification of polymorphic dna analysis. | one hundred and two isolates of escherichia coli o157:h7 derived from cattle were characterised by random amplification of polymorphic dna (rapd). four different rapd profiles were observed. based on the combined results of rapd typing and toxin genotyping, the isolates could be divided into six distinct groups. | 1998 | 9839900 |
| porcine recombinant dihydropyrimidine dehydrogenase: comparison of the spectroscopic and catalytic properties of the wild-type and c671a mutant enzymes. | dihydropyrimidine dehydrogenase catalyzes, in the rate-limiting step of the pyrimidine degradation pathway, the nadph-dependent reduction of uracil and thymine to dihydrouracil and dihydrothymine, respectively. the porcine enzyme is a homodimeric iron-sulfur flavoprotein (2 x 111 kda). c671, the residue postulated to be in the uracil binding site and to act as the catalytically essential acidic residue of the enzyme oxidative half-reaction, was replaced by an alanyl residue. the mutant enzyme wa ... | 1998 | 9860876 |
| the sugarless mutation affects the expression of the white eye color gene in drosophila melanogaster. | investigation of a modifier locus displaying a darker eye phenotype in white-apricot flies led to the isolation of the gene encoding udp-glucose dehydrogenase (udpgdh). the p-element insertion l(3)05007 occurs upstream of the transcription start site of the sugarless (sgl) gene and greatly reduces its transcription at various developmental stages. a single abundant sgl transcript shows a ubiquitous distribution and encodes a 53-kda protein which is 64% identical in sequence to bovine udp-glucose ... | 1998 | 9862465 |
| effect of replacing a conserved proline residue on the function and stability of bovine adrenodoxin. | a proline residue in the c-terminal part of the polypeptide chain is highly conserved among many [2fe-2s] ferredoxins. to investigate the requirement for proline at this position, we constructed steric (4-108w), charged (4-108k), polar (4-108s) and non-polar (4-108a) truncated mutants of adrenodoxin and studied them for biological function and stability. although the variants were expressed in escherichia coli with a significantly lower yield compared with wild-type adrenodoxin, successful incor ... | 1998 | 9876927 |
| use of fortuitous in vitro mutations in a synthetic cu-zn superoxide dismutase gene to illuminate protein structure-function relationships. | a completely synthetic bovine copper-zinc superoxide dismutase gene (cu-znsod), designed using the most favoured codons for expression in yeast, was constructed. fortuitous mutations introduced while cloning the synthetic gene permitted the additional construction of four altered-polypeptide products representing two single (pro121-->leu and gly128-->asp), one double (pro100-->leu, arg113-->lys) and one triple (pro100-->leu, arg113-->lys, pro121-->leu) mutant. all five versions of the gene were ... | 1998 | 9876930 |
| bovine torovirus: sequencing of the structural genes and expression of the nucleocapsid protein of breda virus. | breda virus (brv), a member of the genus torovirus, is an established etiological agent of diarrhea of cattle, which is found as two separate serotypes, brv-1 and brv-2. in this study, a 7.5 kb fragment of the brv-1 genome that bracketed the genes for the structural proteins of brv was amplified by long rt-pcr and the amplicon purified and sequenced directly. sequence analysis revealed the presence of four open reading frames (orf) corresponding to the peplomer (s), envelope (m), and nucleocapsi ... | 1998 | 9879765 |
| cloning, expression, purification, and immunocharacterization of placental protein-14. | human placental protein-14 (pp-14), a member of the lipocalin superfamily, shares homology at the level of the primary and secondary structures with bovine beta-lactoglobulin. it is the most prominent endometrial protein synthesized by the glandular cells of endometrium under estrogen priming and progesterone stimulation. the temporal and spatial expression of pp-14 in the female reproductive tract combined with its biological activities ex vivo suggest that this glycoprotein probably plays an e ... | 1998 | 9882566 |
| comparative study of five different techniques for epidemiological typing of escherichia coli o157. | a set of 47 austrian human, food, and veterinary escherichia coli o157:h7 isolates was used to evaluate five different epidemiological typing methods. ribotyping using an automated microbial characterization system (riboprinter) was not suitable for detection of epidemiological relatedness. all but one e. coli strain were typeable by phage typing. random amplified polymorphic dna-pcr fingerprinting was performed using primer m13 containing the sequence 5'-gag ggt ggc ggt tct-3' and primer 1247 ( ... | 1998 | 9884832 |
| effect of cephapirin and mecillinam on the phagocytic and respiratory burst activity of neutrophil leukocytes isolated from bovine blood. | antimicrobial therapy is the most commonly used treatment of bacterial infections in dairy cows. polymorphonuclear neutrophil leukocytes (pmn) play an important role in the first line defence against invading bacteria and it is important that the function of pmn is not compromised by antibiotics. we investigated the in vitro effect of cephapirin, a first generation cephalosporin, and mecillinam, an amidinopenicillin with activity against mainly gram-negative bacteria, on phagocytosis and respira ... | 1998 | 9885963 |
| vaccines and diagnostic methods for bovine mastitis: fact and fiction. | a number of problems are uniquely associated with vaccination of dairy cows for mastitis. one of these is that the number of mastitis pathogens is numerous and heterogeneous. vaccine efforts have concentrated mainly on the major mastitis pathogens. while at least one s. aureus bacterin has been commercially available for a number of years, no large-scale, independent field trials have been published in refereed journals which support the efficacy of this vaccine. experimental vaccines for s. aur ... | 1999 | 9890021 |
| transcriptional inhibition of the operon for the spermidine uptake system by the substrate-binding protein potd. | inhibition of spermidine uptake in escherichia coli, which occurs in the presence of accumulated polyamines, has been studied using the spermidine uptake operon consisting of the pota, -b, -c, and -d genes. transcription of the potabcd operon was inhibited by potd, a spermidine-binding protein usually found in the periplasm, and the inhibitory effect of potd was increased by spermidine. transcription was not affected by bovine serum albumin, pota, or potf, suggesting that the effects of potd are ... | 1999 | 9890949 |
| roles of pilc and pile proteins in pilus-mediated adherence of neisseria gonorrhoeae and neisseria meningitidis to human erythrocytes and endothelial and epithelial cells. | unlike other type 4 pili, the neisserial pili consist of at least two distinct proteins, the highly variable major subunit pile forming the pilus fiber and the tip-associated adhesin pilc. pilc protein purified either from gonococci or from escherichia coli interacted with different human epithelial cell lines, primary epithelial and endothelial cells. the binding of pilc protein efficiently prevented the attachment of piliated neisseria gonorrhoeae and neisseria meningitidis to these cell types ... | 1999 | 9916098 |
| role of carboxyl-terminal charges on s-modulin membrane affinity and inhibition of rhodopsin phosphorylation. | s-modulin shows a higher affinity for urea-stripped frog rod outer segment membranes than s26 (a cone homologue of s-modulin). nacl at a concentration of several hundred millimolar reduced the membrane affinity of s-modulin to the s26 level. chimeric s-modulin and s26 whose respective 23 and 29 amino acids at the carboxyl terminus were swapped showed membrane affinites similar to those of s26 and s-modulin, respectively. the membrane affinity of an s-modulin mutant lacking c-terminal positive ch ... | 1999 | 9930992 |
| cryptosporidium and concurrent infections with other major enterophatogens in 1 to 30-day-old diarrheic dairy calves in central spain. | faeces samples from 218, 1 to 30-day-old, diarrheic dairy calves in 65 dairy herds were screened for the presence of cryptosporidium and concurrent infections with rotavirus, coronavirus, f5 escherichia coli and salmonella spp. calves were grouped according to their age as follows: 1-7, 8-14, 15-21 and 22-30 days. cryptosporidium infection was detected in 43.8%, 71.9%, 63.2% and 6.9% of the calves in the respective age groups. significant differences in the detection rate of cryptosporidium were ... | 1999 | 9950342 |
| pregnancy-associated glycoprotein and decreased polymorphonuclear leukocyte function in early post-partum dairy cows. | phagocytosis and oxidative burst activity of polymorphonuclear neutrophil leukocytes (pmn) isolated from blood and pregnancy-associated glycoprotein (bpag) concentrations in plasma were evaluated in two longitudinal studies in dairy cows from 3 weeks before until 5 weeks after calving, carried out in the united states and in europe. ingestion of staphylococcus aureus by blood pmn increased during the first week after calving and normalised 3 weeks post-partum. phagocytosis of escherichia coli di ... | 1999 | 9950353 |
| the susceptibility of gram-negative rods and their adaptive forms resistant to colistine to the bactericidal action of sera. | the susceptibility of escherichia coli k1, salmonella enteritidis, salmonella typhimurium strains and their adaptative forms resistant to colistine (colr forms) was compared with respect to their sensitivity to the bactericidal action of normal cord serum and normal bovine serum. it has been shown that the colr forms are more susceptible to sera as compared to initial strains. the increase of sensitivity of the colr forms is connected with structural changes within bacterial cell wall which is t ... | 1998 | 9990711 |
| recurrent clinical mastitis caused by escherichia coli in dairy cows. | in this study, the occurrence of persistent intramammary infections caused by escherichia coli with recurrent episodes of clinical mastitis caused by e. coli are described for a cohort of 300 dutch dairy herds. calculations on the recurrent episodes were based on data collected by dairy farmers. the genotype of the e. coli strains was determined by means of a polymerase chain reaction using enterobacterial repetitive intergenic consensus (eric) primers, resulting in a dna fingerprint. quarters i ... | 1999 | 10022009 |
| influence of oxygen availability on physiology, verocytotoxin expression and adherence of escherichia coli o157. | a strain of escherichia coli serotype o157 was grown in steady state chemostat culture under aerobic, oxygen-limited and anaerobic conditions. the growth and metabolic efficiency of oxygen-limited and anaerobic cultures was impaired, with biomass yield and the molar growth yield for glucose, yglucose, reduced markedly in comparison with aerobic cultures. steady state cells were typically short rods 2-3 microns long, and were encapsulated by a layer of extracellular material. the majority of cell ... | 1999 | 10030015 |
| escherichia coli o157:h7 in retail ground beef in seattle: results of a one-year prospective study. | escherichia coli o157:h7 was sought systematically in 1,400 samples of retail ground beef in seattle in a 1-year prospective study. sorbitol-nonfermenting, lactose-fermenting, indole-positive colonies isolated after enrichment culture were probed for the presence of shiga toxin genes. totals of 67,040 sorbitol-nonfermenting and 66,705 sorbitol-fermenting colonies were characterized, but e. coli o157:h7 was not identified. the sensitivity of this technique was usually sufficient to detect e. coli ... | 1999 | 10030631 |
| cytochrome p450c17-expressing escherichia coli as a first-step screening system for 17alpha-hydroxylase-c17,20-lyase inhibitors. | we have designed and synthesized a number of cytochrome p450 17alpha-hydroxylase-c17,20-lyase (p450c17) inhibitors with the aim of inhibiting androgen synthesis. to select the most potent inhibitors, we initially used human testicular microsomes, which have a high level of expression of this enzyme. however, due to lack of availability of human tissue and variability among the samples, we utilized recombinant human enzyme expressed in escherichia coli. we designed a simple and economical protoco ... | 1999 | 10036137 |
| assessment of the adequacy of cleaning of equipment used for breaking beef carcasses. | enumeration of bacteria on product entering or leaving a beef carcass breaking process showed that the meat was being contaminated with escherichia coli during the process. the equipment used in the process appeared to be well cleaned, and few bacteria were recovered from meat-contacting surfaces of cleaned equipment. however, careful inspection of the cleaned equipment revealed obscured locations in the equipment which harboured detritus that carried large numbers of aerobic bacteria including ... | 1999 | 10050680 |
| collaborative evaluation of detection methods for escherichia coli o157:h7 from radish sprouts and ground beef. | for the evaluation of plating and immunological methods applicable to the detection of escherichia coli o157:h7 from ground beef and radish sprouts, a collaborative study was conducted. it focused on a comparison of the efficiency of the plating and immunological methods using various plating agars and immuno-kits in combination with enrichment in modified e. coli broth supplemented with novobiocin (mec + n), and using immunomagnetic separation. the plating media tested were sorbitol macconkey a ... | 1999 | 10050682 |
| characterization of rpos alleles in escherichia coli o157:h7 and in other e. coli serotypes. | the rpos nucleotide and predicted amino acid sequences from three escherichia coli o157:h7 isolates were compared with those from three other e. coli isolates, including the likely o157:h7 progenitor, e. coli o55:h7. these clinical and environmental isolates all had identical sigma s amino acid sequences, while laboratory strains k12 and dh1 had three and one amino acid alterations, respectively, in comparison with the majority sequence. to extend the analysis of sigma s sequence conservation to ... | 1999 | 10063629 |