Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| phenoxazine compounds produced by the reactions with bovine hemoglobin show antimicrobial activity against non-tuberculosis mycobacteria. | we studied the anti-microbial effects of phenoxazines produced by the reaction of o-aminophenol or its derivatives with bovine hemoglobin, on seven species of mycobacteria such as mycobacterium tuberculosis, mycobacterium marinum, mycobacterium intracellulare, mycobacterium scrofulaceum, mycobacterium fortuitum, mycobacterium kansasii and mycobacterium smegmatis and some bacteria such as escherichia coli, pseudomonas aeruginosa, salmonella enterica serovar typhimurium, staphylococcus aureus, lis ... | 2004 | 15185971 |
| high prevalence of enterohemorrhagic escherichia coli (ehec) o157 from cattle in selected regions of japan. | the prevalence of enterohemorrhagic escherichia coli (ehec) o157 was examined in bovine faeces. ehec o157 was isolated from the faeces of 42 (13.0%) of 324 cattle. of the 4 farms and the facilities tested, the 3 farms and the facilities were found positive for ehec o157. the highest isolation rate among the farms was 33.7%. the prevalence of ehec o157 in heifers was higher than that in calves and other cattle. no cattle positive for ehec o157 showed any clinical signs except 2 calves with diarrh ... | 2004 | 15187376 |
| effect of recombinant cytokines on leucocytes and physiological changes in bovine mammary glands during early involution. | we examined the effects of administering recombinant bovine cytokines to non-lactating dairy cows and measured mammary gland leucocytes and the involution process. after the final milking, groups of cows were given an intramammary infusion of cytokine in two quarters. these cytokines were recombinant bovine interleukin-2 (rboll-2) (2 x 10(5) units, n = 6), recombinant bovine granulocyte-macrophage colony stimulating factor (rbogm-csf) (500 microg, n = 4) and recombinant bovine interleukin-1beta ... | 2004 | 15190942 |
| mild to moderate clinical mastitis: efficacy of intramammary amoxicillin, frequent milk-out, a combined intramammary amoxicillin, and frequent milk-out treatment versus no treatment. | study objectives were to determine the efficacy of 4 methods (intramammary amoxicillin, frequent milk-out, a combined intramammary amoxicillin and frequent milk-out, and no treatment) of managing mild to moderate clinical mastitis in a university dairy herd. clinical and microbiological cures, milk production, disease progression, and california mastitis tests scores were evaluated. cows meeting the study criteria were assigned to one of four treatment options based on a systematic randomization ... | 2004 | 15202642 |
| crystallization and preliminary x-ray diffraction study of mammalian mitochondrial seryl-trna synthetase. | the mitochondrial seryl-trna synthetase (mt serrs) from bos taurus was overexpressed in escherichia coli and crystallized using the sitting-drop vapour-diffusion method. crystals grew in a very narrow range of conditions using peg 8000 as precipitant at room temperature. an appropriate concentration of lithium sulfate was critical for crystal nucleation. crystals diffracted well beyond a resolution of 1.6 a and were found to belong to the orthorhombic space group c222(1), with unit-cell paramete ... | 2004 | 15213404 |
| prevalence estimation and risk factors for escherichia coli o157 on dutch dairy farms. | to estimate the prevalence of escherichia coli o157 on dutch dairy herds, faecal samples were collected once from 678 randomly selected dairy farms in the period october 1996-december 2000. samples were cultured for e. coli o157. thirty-eight isolates were tested for virulence genes (eae, vt1 and vt2). a questionnaire about farm characteristics was taken from the farm manager, resulting in variables that could be analysed to identify and quantify factors associated with presence of e. coli o157. ... | 2004 | 15219969 |
| effect on bovine lactoferrin on the activation of the enteroinvasive bacterial type iii secretion system. | shigella and enteroinvasive escherichia coli (eiec) strains secrete virulence proteins by a complex machinery called the type iii secretion (tts) apparatus. secretion of virulence proteins is a tightly-regulated phenomenon such that the tts system is weakly active when bacteria are grown in common laboratory media. activation of the tts system is triggered by contact with eukaryotic cells, or can be artificially stimulated by the addition of congo red dye to the growth medium. exploiting the abi ... | 2004 | 15222475 |
| bacterial growth during the early phase of infection determines the severity of experimental escherichia coli mastitis in dairy cows. | the aim of this study was to investigate the importance of bacterial growth for the severity of experimental escherichia coli mastitis, indirectly expressed as the area under the curve of bacterial counts in milk over time. the association of pre-infusion somatic cell count and post-infusion influx of inflammatory cells in milk with severity of infection was also examined. bacterial growth was studied through culture in milk samples (in vitro) and through monitoring of bacterial counts in milk d ... | 2004 | 15223122 |
| quantity and quality of runoff from a beef cattle feedlot in southern alberta. | southern alberta, which has a cold climate dominated by strong chinook winds, has the highest density of feedlot cattle in canada. however, the quantity and quality of runoff from beef cattle (bos taurus) feedlots in this unique region has not been investigated. our objectives were to compare runoff quantity (1998-2002) with catch-basin design criteria; determine concentrations of selected inorganic chemical parameters (1998-2000) in runoff in relation to water quality guidelines and the potenti ... | 2004 | 15224948 |
| heme a synthase does not incorporate molecular oxygen into the formyl group of heme a. | heme a is an obligatory cofactor in all eukaryotic and many prokaryotic cytochrome c oxidases. the final step in heme a biosynthesis requires the oxidation of the c8 methyl substituent on pyrrole ring d to an aldehyde, a reaction catalyzed by heme a synthase. to effect this transformation, heme a synthase is proposed to utilize a heme b cofactor, oxidizing the substrate via successive monooxygenase reactions. consistent with this hypothesis, the activity of heme a synthase is found to be strictl ... | 2004 | 15236569 |
| prevalence and characteristics of escherichia coli o157 from major food animals in korea. | escherichia coli o157:h7/nm (e. coli o157) is now recognized as an important cause of diarrhea, hemorrhagic colitis and hemolytic-uremic syndrome worldwide. there have been several cases of human e. coli o157 infection in korea since it was first isolated from a patient with hemolytic-uremic syndrome in 1998. meat, other foods, and recreational and drinking water contaminated with animal feces are probably the major sources of the e. coli o157 infection. in this study, we investigated the preval ... | 2004 | 15240073 |
| microbiological conditions of mechanically tenderized beef cuts prepared at four retail stores. | a group of 25 retail cuts of mechanically tenderized beef prepared during usual commercial operations at store facilities were obtained from each of four retail stores. aerobes, coliforms, escherichia coli and organisms that formed black or grey colonies on harlequin agar (ha), a medium formulated for the recovery of listeria, were enumerated in samples from the surfaces and the deep tissues of cuts. for the four groups of cuts, the mean numbers of aerobes on the surfaces of cuts differed by <1 ... | 2004 | 15240079 |
| characterization of immunodominant linear b-cell epitopes on the carboxy terminus of the rinderpest virus nucleocapsid protein. | the nucleocapsid (n) protein of rinderpest virus (rpv) is one of the most abundant and immunogenic viral proteins expressed during natural or experimental infection. to identify immunogenic epitopes on the n protein, different forms of rpv n protein, including the full-length protein (n(1-525)), an amino-terminal construct (n(1-179)), and a carboxy-terminal construct (n(414-496)), were expressed in escherichia coli as glutathione s-transferase (gst) fusion proteins. the antigenicity of each reco ... | 2004 | 15242937 |
| three-dimensional solution structure of the cytoplasmic b domain of the mannitol transporter iimannitol of the escherichia coli phosphotransferase system. | the solution structure of the cytoplasmic b domain of the mannitol (mtl) transporter (ii(mtl)) from the mannitol branch of the escherichia coli phosphotransferase system has been solved by multidimensional nmr spectroscopy with extensive use of residual dipolar couplings. the ordered iib(mtl) domain (residues 375-471 of ii(mtl)) consists of a four-stranded parallel beta-sheet flanked by two helices (alpha(1) and alpha(3)) on one face and helix alpha(2) on the opposite face with a characteristic ... | 2004 | 15258141 |
| short communication: influence of staphylococcus aureus intramammary infection on serum copper, zinc, and iron concentrations. | the goal of the present study was to characterize changes in serum trace mineral concentrations in cattle with experimentally induced staphylococcus aureus mastitis. nine primiparous holstein-friesian cattle were challenged with approximately 150 cfu of staph. aureus atcc29740 by intramammary infusion on d 6, 7, and 8 of lactation. serum cu, zn, and fe concentrations were determined immediately before and at 24, 48, and 72 h after the final intramammary infusion of staph. aureus. infection statu ... | 2004 | 15259232 |
| all-trans retinoic acid is increased in the acute phase-related hyporetinemia during escherichia coli mastitis. | blood vitamin a profiles, including concentrations of retinol and its active metabolite retinoic acid, were assessed during the peripartum period and during experimentally induced escherichia coli mastitis in heifers. serum retinol decreased in all animals in the immediate postpartum period and normalized within 1 wk after parturition. no significant changes were detectable in the concentrations of retinoic acid isomers during puerperium. following intramammary e. coli infusion, all cows showed ... | 2004 | 15259233 |
| localization of a 56-kda antigen that is present in multiple developmental stages of neospora caninum. | the purpose of the present study was to characterize the intracellular distribution of a native neospora caninum 56-kda protein that is recognized by sera from n. caninum-infected dairy cattle. the complementary dna coding for this protein was expressed in escherichia coli as a polyhis fusion protein to which antiserum was prepared and used to localize the antigen in n. caninum tachyzoites and bradyzoites. by sodium dodecylsulfate-polyacrylamide gel electrophoresis and immunoblotting, antirecomb ... | 2004 | 15270121 |
| persistence of enterohemorrhagic escherichia coli o157:h7 in soil and on leaf lettuce and parsley grown in fields treated with contaminated manure composts or irrigation water. | outbreaks of enterohemorrhagic escherichia coli o157:h7 infections associated with lettuce and other leaf crops have occurred with increasing frequency in recent years. contaminated manure and polluted irrigation water are probable vehicles for the pathogen in many outbreaks. in this study, the occurrence and persistence of e. coli o157:h7 in soil fertilized with contaminated poultry or bovine manure composts or treated with contaminated irrigation water and on lettuce and parsley grown on these ... | 2004 | 15270487 |
| microbiological quality of ground beef from conventionally-reared cattle and "raised without antibiotics" label claims. | the contamination of the food supply with pathogens and antimicrobial-resistant bacteria has emerged as an important health concern. we compared the microbiological quality of 77 samples of ground beef from conventionally raised cattle with 73 samples of ground beef from cattle raised without antimicrobial agents. contamination with coliforms (1.7 log cfu/g) and escherichia coli (0.51 log cfu/g) and shiga toxin 2-producing e. coli (6% prevalence) was similar in both sample groups. neither salmon ... | 2004 | 15270497 |
| campylobacter prevalence in lactating dairy cows in the united states. | the objective of the present study was to determine the prevalence of intestinal campylobacter in lactating dairy cows from various regions of the united states. participating commercial dairy farms were chosen at random and were part of a national survey to determine e. coli o157:h7 and salmonella prevalence in dairy cows. farms had no previous history of campylobacter problems. fecal samples were collected rectally from 720 cows on farms in the northeast (four farms), in the desert southwest ( ... | 2004 | 15270504 |
| endocrine aspects in pathogenesis of mastitis in postpartum dairy cows. | in well-managed dairy herds some environmental pathogens including gram-negative (gn) strains (e. coli and others) have been recognized recently as the predominant causative microbes of mastitis in the peri-parturient period. in early weeks of lactation hyperketonaemia may predispose the high-producing cows for gn mastitis. in gn mastitis cytokines, eicosanoids and oxygen radicals are released, which are responsible for the local and systemic symptoms. experimental administration of endotoxin in ... | 2004 | 15271468 |
| direct binding of visual arrestin to microtubules determines the differential subcellular localization of its splice variants in rod photoreceptors. | proper function of visual arrestin is indispensable for rapid signal shut-off in rod photoreceptors. dramatic light-dependent changes in its subcellular localization are believed to play an important role in light adaptation of photoreceptor cells. here we show that visual arrestin binds microtubules. the truncated splice variant of visual arrestin, p44, demonstrates dramatically higher affinity for microtubules than the full-length protein (p48). enhanced microtubule binding of p44 underlies it ... | 2004 | 15272005 |
| characterization of the human mitochondrial methionyl-trna synthetase. | human mitochondrial methionyl-trna synthetase (human mtmetrs) has been identified from the human est database. the cdna encodes a 593 amino acid protein with an 18 amino acid mitochondrial import signal sequence. sequence analysis indicates that this protein contains the consensus motifs characteristic of a class i aminoacyl-trna synthetase but lacks the zn(2+) binding motif and c-terminal dimerization region found in metrss from various organisms. the mature form of human mtmetrs has been clone ... | 2004 | 15274629 |
| resonance raman detection of the fe2+-c-n modes in heme-copper oxidases: a probe of the active site. | resonance raman spectroscopy has been employed to investigate the reduced cyano complexes of cytochrome aa(3) from bovine heart and rhodobacter sphaeroides and of cytochrome bo(3) from e. coli. in the aa(3)-type oxidases, the frequency of the fe-cn stretching mode is located at 468 cm(-1), and the bending fe-c-n vibration, at 500 cm(-1). the fully reduced cytochrome bo(3)-cn complex gives rise to a stretching vibration at 468 cm(-1), a bending vibration at 491 cm(-1), and a stretching c-n vibrat ... | 2004 | 15285666 |
| characterisation of attaching-effacing escherichia coli isolated from animals at slaughter in england and wales. | escherichia coli isolates were recovered from faecal samples taken from cattle, sheep and pigs at slaughter in england and wales. isolates (n = 1227) selected at random from this collection were each hybridised in colony dot-blot experiments with an eae gene probe that presumptively identified attaching-effacing e. coli (aeec). of the 99 (8.1%) eae positive isolates 72 were of ovine origin, 24 were of bovine origin and three of porcine origin. none were typed as o157:h7 whereas 78 were assigned ... | 2004 | 15288926 |
| differential effects of steroids and retinoids on bovine myelopoiesis in vitro. | pregnancy and parturition are associated with physiological changes caused by steroid hormones. alterations in number, maturity, and function of polymorphonuclear leukocytes observed in dairy cows at parturition suggest a common causative relationship with steroid hormones. this study was designed to investigate the effects of progesterone, 17-beta-estradiol, and hydrocortisone on the proliferation of bovine progenitor cells. an in vitro culturing system was used, and colonies were scored after ... | 2004 | 15290966 |
| sample size, library composition, and genotypic diversity among natural populations of escherichia coli from different animals influence accuracy of determining sources of fecal pollution. | a horizontal, fluorophore-enhanced, repetitive extragenic palindromic-pcr (rep-pcr) dna fingerprinting technique (hferp) was developed and evaluated as a means to differentiate human from animal sources of escherichia coli. box a1r primers and pcr were used to generate 2,466 rep-pcr and 1,531 hferp dna fingerprints from e. coli strains isolated from fecal material from known human and 12 animal sources: dogs, cats, horses, deer, geese, ducks, chickens, turkeys, cows, pigs, goats, and sheep. hfer ... | 2004 | 15294775 |
| rectal administration of escherichia coli o157:h7: novel model for colonization of ruminants. | escherichia coli o157:h7 causes hemorrhagic colitis and life-threatening complications. because healthy cattle are reservoirs for the bacterium, ruminant infection models have applications in analyzing the relationship between cattle and this human pathogen and in testing interventions to reduce or prevent bovine colonization with this bacterium. current approaches often do not reliably mimic natural, long-term bovine colonization with e. coli o157:h7 in older calves and adult animals (ages that ... | 2004 | 15294790 |
| a three-year study of enterohemorrhagic escherichia coli o157 on a farm in japan. | a long-term study was performed on the prevalence of enterohemorrhagic escherichia coli (ehec) o157 in bovine faeces. the present study was conducted on heifers raised on a farm showing a high isolation rate of ehec o157 in previous years. the prevalence of ehec o157 isolated from faecal samples was 10.6% (222/2104), 5.6% (181/3225), and 5.6% (153/2744) from 1998 to 2000, respectively. the numbers of ehec o157-positive heifers for the same 3 years were 46.3% (185/400), 36.8% (147/399), and 31.7% ... | 2004 | 15297748 |
| the efficacy of bovine lactoferrin in the treatment of cows with experimentally induced escherichia coli mastitis. | the effect of bovine lactoferrin (lf) was studied in experimental escherichia coli mastitis, using enrofloxacin as a comparator. mastitis was induced in six clinically healthy primiparous dairy cows by infusing 1500 colony-forming units of e. coli into a single udder quarter. the challenge was repeated into a contralateral quarter of the same cows 3 weeks later. at the first challenge, three cows were treated with 1.5 g of bovine lactoferrin intramammarily three times (12, 20 and 36 h postchalle ... | 2004 | 15305847 |
| effect of antibiotics in milk replacer on fecal shedding of escherichia coli o157:h7 in calves. | the objective of this study was to compare the concentration and duration of fecal shedding of escherichia coli o157:h7 between calves fed milk replacer with or without antibiotic (oxytetracycline and neomycin) supplementation. eighteen 1-wk-old holstein calves were orally inoculated with a strain of e. coli o157:h7 (3.6 x 10(8) cfu/calf) made resistant to nalidixic acid (na). rectal samples were obtained three times weekly for 8 wk following oral inoculation. fecal shedding of na-resistant e. c ... | 2004 | 15309963 |
| antibiotic resistance among enterotoxigenic escherichia coli from piglets and calves with diarrhea. | in vitro resistance to 8 antimicrobials among enterotoxigenic escherichia coli from piglets and calves over a 13-year period was evaluated. least resistance occurred against ceftiofur for all, followed by apramycin and gentamicin for porcine and florfenicol for bovine isolates. no significant differences were found between the first 8 and last 5 years. | 2004 | 15317393 |
| iron uptake by escherichia coli cultured with antibodies from cows immunized with high-affinity ferric receptors. | the synergistic effects of immunoglobulin g (igg) from cows vaccinated with ferric citrate receptor (feca) and igg from cows vaccinated with ferric enterobactin receptor (fepa) were measured in an in vitro iron uptake assay. serum was isolated and pooled within treatment from five cows each vaccinated with fepa or feca or not vaccinated. immunoglobulin g was isolated by ammonium sulfate precipitation and protein g affinity chromatography. six escherichia coli isolates from bovine intramammary in ... | 2004 | 15328222 |
| influence of animal origin and lineage on survival of escherichia coli o157:h7 strains in strong and weak acid challenges. | twenty-five strains of escherichia coli o157:h7 isolated from humans, cattle, and pigs were maintained in hcl (ph 2.5) and in a volatile fatty acid (vfa) mixture (ph 4.0) for up to 6 h at 37 degrees c to assess their ability to survive in acidic conditions that simulate those of the stomach and ileum, respectively. in hcl, the average group survival of bovine strains was significantly higher than that of porcine and human strains, whereas in vfas, porcine strains were significantly more resistan ... | 2004 | 15330520 |
| high numbers of shiga toxin-producing escherichia coli found in bovine faeces collected at slaughter in japan. | the prevalence and concentration of shiga toxin-producing escherichia coli (stec) in cattle faeces (n=605) at the time of slaughter was studied in shimane prefecture, japan on a monthly basis between april 2000 and march 2001. screening with stx-pcr determined a prevalence of 37.5%. after analysis of spread faeces and enriched samples on cefixime, tellurite and sorbitol-macconkey agar using hcl treatment, 114 stec strains were singly or concomitantly isolated from 97 cattle (15.9%). of the 605 c ... | 2004 | 15336421 |
| cryopreserved bovine mammary cells to model epithelial response to infection. | mammary gland epithelial cells are likely to be important effectors in defending against mastitis, yet little is known about their response mechanisms. here, we describe a cryopreserved bovine mammary epithelial cell model to study the infection response. primary cell cultures from four holstein cows were prepared, and frozen after two passages. the cell cultures from each cow were then thawed and maintained separately, yet simultaneously, and exposed to treatments that included infection with s ... | 2004 | 15350749 |
| changes of physicochemical indicators during mastitis and the effects of milk ejection on their sensitivity. | we examined the relationship between physicochemical indicators and somatic cells in the milk of dairy cows during experimentally induced mastitis and their significance as indicators for use in controlling udder health. we were concerned particularly with the effect of alveolar milk ejection on the sensitivity of these indicators. in expt 1, escherichia coli lipopolysaccharide (esch. coli lps) was injected into the left rear quarter to induce an inflammatory reaction in one quarter in each of s ... | 2004 | 15354578 |
| identification of intracellular target proteins of the calcium-signaling protein s100a12. | in this report, we have focused our attention on identifying intracellular mammalian proteins that bind s100a12 in a ca2+-dependent manner. using s100a12 affinity chromatography, we have identified cytosolic nadp+-dependent isocitrate dehydrogenase (idh), fructose-1,6-bisphosphate aldolase a (aldolase), glyceraldehyde-3-phosphate dehydrogenese (gapdh), annexin v, s100a9, and s100a12 itself as s100a12-binding proteins. immunoprecipitation experiments indicated the formation of stable complexes be ... | 2004 | 15355353 |
| fecal contamination of pastoral wetlands. | near-channel hill-country wetlands draining steep pastoral land in new zealand exhibit high levels of fecal contamination at a range of flows. this contamination is attributed to both the transport of bacteria into a wetland from the surrounding catchment and the direct excretion of fecal material onto wetlands by grazing cattle. e. coli concentrations observed at low to moderate flow at 20 sites varied between 0.5 x 10(1) and 2 x 10(4) most probable number (mpn) 100 ml(-1). high flow concentrat ... | 2004 | 15356253 |
| the incidence of shiga toxin-producing escherichia coli in cattle with mastitis in brazil. | to determine the prevalence and molecular characteristics of shiga toxin-producing escherichia coli (stec) isolates from bovine mastitic milk in brazil. | 2004 | 15357736 |
| the distribution of, and antibody response to, the core lipopolysaccharide region of escherichia coli isolated from the faeces of healthy humans and cattle. | there are five different core types of escherichia coli lipopolysaccharide (lps), and enterohaemorrhagic e. coli tend to have the r3 core type. it has been hypothesized that increased carriage of bacteria with a specific core type will induce higher levels of antibodies and protect against disease caused by bacteria carrying that specific lps core. approximately 320 isolates of e. coli, half from healthy human faeces and half from healthy bovine faeces have been core typed both by core-specific ... | 2004 | 15358817 |
| phage types and genotypes of shiga toxin-producing escherichia coli o157:h7 isolates from humans and animals in spain: identification and characterization of two predominating phage types (pt2 and pt8). | phage typing and dna macrorestriction fragment analysis by pulsed-field electrophoresis (pfge) were used for the epidemiological subtyping of a collection of shiga toxin-producing escherichia coli (stec) o157:h7 strains isolated in spain between 1980 and 1999. phage typing distinguished a total of 18 phage types among 171 strains isolated from different sources (67 humans, 82 bovines, 12 ovines, and 10 beef products). however, five phage types, phage type 2 (pt2; 42 strains), pt8 (33 strains), p ... | 2004 | 15364983 |
| modulating effect of serum on the stimulation of plasminogen activator inhibitor 2 production in human gingival fibroblasts by lipopolysaccharide and interleukin-1beta. | plasminogen activator inhibitor-2 (pai-2) is an important counter proteolysis factor which helps protect tissues from inflammatory stress. the expression of pai-2 can be modulated by various inflammatory stimulants and mediators. the aim of the present study was to investigate how serum factors, might modulate the effects of lipopolysaccharide (lps) and interleukin-1beta on pai-2 production by human gingival fibroblasts. | 2004 | 15368874 |
| comparison of a membrane surface adhesion recovery method with an ims method for use in a polymerase chain reaction method to detect escherichia coli o157:h7 in minced beef. | in this study, enrichment procedures and two recovery methods, a membrane surface adhesion technique and an immunomagnetic separation (ims), were compared for use in conjunction with a multiplex polymerase chain reaction (pcr) method with a view to describing a fast (24 h) and economical test for detection of escherichia coli o157:h7 in meat samples. the study showed no significant difference between three different enrichment media (bhi, e. coli (e.c.) broth+novobiocin, modified tryptone soya b ... | 2004 | 15369860 |
| a european survey of antimicrobial susceptibility among zoonotic and commensal bacteria isolated from food-producing animals. | to study antimicrobial resistance in zoonotic bacteria isolated from food animals in different countries using uniform methodology. | 2004 | 15375107 |
| water and ion permeation in baqp1 and glpf channels: a kinetic monte carlo study. | the kinetic monte carlo reaction-path-following technique is applied to determine the lowest-energy water pathway and the coordinating amino acids in baqp1 and glpf channels, both treated as rigid. in baqp1, water molecules pass through the pore between the asparagine-proline-alanine (npa) and selectivity filter (sf) sites one at a time. the water chain is interrupted at the sf where one water forms three stable hydrogen bonds with protein atoms. in this sf, water's conformation depends on the p ... | 2004 | 15377535 |
| dose dependency and individual variability of the lipopolysaccharide-induced bovine acute phase protein response. | in order to investigate the dose dependency and the individual variability of the lipopolysaccharide (lps)-induced acute phase protein response in cattle, 8 nonlactating, nonpregnant danish holstein cows were challenged 3 times each by intravenous injection of increasing doses (10, 100, and 1000 ng/kg, consecutively) of escherichia coli lps with 3-wk intervals. all 3 lps doses resulted in a rapid increase in serum concentrations of haptoglobin and serum amyloid a (saa) and a decrease in serum co ... | 2004 | 15377612 |
| effect of pathogen-specific clinical mastitis on milk yield in dairy cows. | our objective was to estimate the effects of the first occurrence of pathogen-specific clinical mastitis (cm) on milk yield in 3071 dairy cows in 2 new york state farms. the pathogens studied were streptococcus spp.,staphylococcus aureus, staphylococcus spp., escherichia coli, klebsiella spp., arcanobacterium pyogenes, other pathogens grouped together, and "no pathogen isolated." data were collected from october 1999 to july 2001. milk samples were collected from cows showing signs of cm and wer ... | 2004 | 15377615 |
| intergenic regions in the rhoptry associated protein-1 (rap-1) locus promote exogenous gene expression in babesia bovis. | members of the babesiarap-1 gene family are expressed during multiple parasite stages, and are regulated by both transcriptional and post-transcriptional mechanisms. in all babesia species, tandemly arranged rap-1 gene copies are separated by an intergenic (ig) region that is hypothesized to regulate gene expression. in this study, we tested that hypothesis by determining whether the babesia bovisrap-1 ig region could promote extra-chromosomal expression of exogenous genes introduced into merozo ... | 2004 | 15380689 |
| a nonradiometric, high-throughput assay for poly(adp-ribose) glycohydrolase (parg): application to inhibitor identification and evaluation. | the enzyme poly(adp-ribose) glycohydrolase (parg) catalyzes the hydrolysis of glycosidic bonds of adp-ribose polymers, producing monomeric adp-ribose units. thus, in conjunction with poly(adp-ribose) polymerase (parp), parg activity regulates the extent of in vivo poly(adp-ribosyl)ation. small molecule inhibitors of parp and parg have shown considerable promise in cellular models of ischemia-reperfusion injury and oxidative neuronal cell death. however, currently available parg inhibitors are no ... | 2004 | 15450800 |
| ascophyllum nodosum supplementation: a preharvest intervention for reducing escherichia coli o157:h7 and salmonella spp. in feedlot steers. | ascophyllum nodosum (tasco-14) decreased the prevalence of enterohemorrhagic escherichia coli (ehec) o157:h7 in animals fed prior to harvest. tasco-14 was supplemented on a 2% dry matter basis 14 days prior to harvest to determine its effects on ehec and salmonella spp. prevalence. two hundred mixed crossbred steers and heifers (bos indicus x bos taurus), in a large commercial finishing facility, served as experimental units. treatment (trt, n = 100) animals received a steam-rolled corn-based di ... | 2004 | 15453570 |
| detection and characterization of verocytotoxin-producing escherichia coli (vtec) o157 and non-o157 in cattle at slaughter. | between september 2001 to june 2002, 145 samples of bovine caecal content were collected at slaughter for verocytotoxin-producing escherichia coli (vtec) serogroups o157 and non-o157 detection. for e. coli o157 the immunomagnetic-separation technique was performed. the enterohaemolytic phenotype was the target for non-o157 vtec identification. the vero cell assay (vca) was performed for toxic activity detection. the genomic sequence for vt1, vt2 and intimin (vt1, vt2, eae genes) were identified ... | 2004 | 15460528 |
| distribution of escherichia coli o157 in bovine fecal pats and its impact on estimates of the prevalence of fecal shedding. | the distribution of escherichia coli o157 in bovine feces was examined by testing multiple samples from fecal pats and determining the density of e. coli o157 in immunomagnetic separation (ims)-positive fecal samples. the density of e. coli o157 in bovine feces was highly variable, differing by as much as 76,800 cfu g(-1) between samples from the same fecal pat. the density in most positive samples was <100 cfu g(-1), the limit of reliable detection by ims. testing only one 1-g sample of feces p ... | 2004 | 15466508 |
| optimization of an escherichia coli system for cell-free synthesis of selectively n-labelled proteins for rapid analysis by nmr spectroscopy. | cell-free protein synthesis offers rapid access to proteins that are selectively labelled with [15n]amino acids and suitable for analysis by nmr spectroscopy without chromatographic purification. a system based on an escherichia coli cell extract was optimized with regard to protein yield and minimal usage of 15n-labelled amino acid, and examined for the presence of metabolic by-products which could interfere with the nmr analysis. yields of up to 1.8 mg of human cyclophilin a per ml of reaction ... | 2004 | 15479237 |
| intermittent and persistent shedding of escherichia coli o157 in cohorts of naturally infected calves. | we conducted two short-term studies of cohorts of naturally infected calves to determine the prevalence and concentrations of escherichia coli o157 shed in faeces. | 2004 | 15479421 |
| molecular cloning of bovine cardiac muscle heat-shock protein 70 kda and its phosphorylation by camp-dependent protein kinase in vitro. | the 70-kda heat-shock protein (hsp70) has been cloned and sequenced from bovine cardiac muscle. on the basis of sequence features, the gene corresponds to the cytoplasmic form of hsp70. this cardiac hsp70 cdna clone has an open reading frame of 1926 bp coding for 641 amino acids and a predicted molecular mass of 70.25 kda. comparison of the amino acid sequence revealed an extensive sequence identity with other species of hsp70. escherichia coli expressed cardiac hsp70 stimulated a 2-fold increas ... | 2004 | 15491140 |
| chaperone activity and prodan binding at the self-associating domain of erythroid spectrin. | spectrin, the major constituent protein of the erythrocyte membrane skeleton, exhibits chaperone activity by preventing the irreversible aggregation of insulin at 25 degrees c and that of alcohol dehydrogenase at 50 degrees c. the dimeric spectrin and the two subunits, alpha-spectrin and beta-spectrin prevent such aggregation appreciably better, 70% in presence of dimeric spectrin at an insulin:spectrin ratio of 1:1, than that in presence of the tetramer of 25%. our results also show that spectr ... | 2004 | 15492010 |
| [cloning and expression of pituitary prolactin gene in ailuropoda melanoleuca]. | the giant panda (ailuropoda melanoleuca) is an endangered species and indigenous to china. it has been proposed that it has a highly specialized reproductive pattern with low fecundity, but little is known about its basic reproductive biology at molecular level. in this study,the pituitary prolactin (prl) cdna of giant panda was amplified by rt-pcr from pituitary total rna and then cloned, sequenced and submitted to genbank (genbank accession no. ay161285). the sequence analysis revealed that th ... | 2004 | 15493147 |
| [relationship between morphological characteristics of the teat duct and prevalence of intramammary infections with streptococcus agalactiae in dairy cows]. | the objective of the study was to determine the relationship between morphological findings of the surface of teat duct particularly the level of ceratosis and the prevalence of intramammary infections (imi). the study was conducted on a commercial dairy herd housing about 3000 lactating dairy cows. we examined 891 quarters in the middle of lactation. duplicate samples of quarter foremilk were collected monthly. the bacteriological status of quarters was determined according to the recommendatio ... | 2004 | 15503535 |
| escherichia coli o157 cluster evaluation. | we investigated a multistate cluster of escherichia coli o157:h7 isolates; pulsed-field gel electrophoresis subtyping, using a single enzyme, suggested an epidemiologic association. an investigation and additional subtyping, however, did not support the association. confirmating e. coli o157 clusters with two or more restriction endonucleases is necessary before public health resources are allocated to follow-up investigations. | 2004 | 15504278 |
| distribution of escherichia coli o157:h7 within and among cattle operations in pasture-based agricultural areas. | to determine the distribution of escherichia coli o157:h7 in pasture-based cattle production areas. | 2004 | 15524323 |
| age-related decline in carriage of ampicillin-resistant escherichia coli in young calves. | the presence of ampicillin-resistant escherichia coli (amp(r) e. coli) in the fecal flora of calves was monitored on a monthly basis in seven cohorts of calves. calves were rapidly colonized by amp(r) e. coli, with peak prevalence in cohort calves observed in the 4 months after the calves were born. the prevalence of calves yielding amp(r) e. coli in cohorts consistently declined to low levels with increasing age of the calves (p < 0.001). | 2004 | 15528566 |
| the sensitivity of escherichia coli strains with k1 surface antigen and rods without this antigen to the bactericidal effect of serum. | the susceptibility of escherichia coli strains with k1 surface antigen (k1+) and rods without this antigen (k1-) to the bactericidal action of normal bovine serum and human normal cord serum was determined. seventy e. coli strains (35 k1+ and 35 k1-) were isolated from urine obtained from children with urinary tract infections. the strains investigated showed variable sensitivity to the bactericidal action of the sera. e. coli k1+ strains were characterized by lower sensitivity to bactericidal e ... | 2004 | 15530015 |
| serum amyloid a and tnf alpha in serum and milk during experimental endotoxin mastitis. | a cross-over study was conducted to investigate the effect of intramammarily infused lipopolysaccharide (lps) on the acute phase reaction in early (el) and in late (ll) lactation. nine cows received intramammary injections of 100 microg of escherichia coli 0111:b4 lps during el and ll. the severity of each cows systemic and local signs and change in milk appearance were recorded and scored throughout the experiment. systemic and local signs were found to be more serious in el cows. tumor necrosi ... | 2004 | 15535955 |
| efficacy of an escherichia coli j-5 mutant strain bacterin in the protection of calves from endotoxin disease caused by subcutaneous challenge with endotoxins from escherichia coli. | the purpose of this trial was to examine the potential of a new escherichia (e) coli j-5 mutant strain bacterin to reduce the severity of clinical disease caused by subcutaneous challenge with endotoxins of gram-negative bacteria in calves. day-old to 3-day old calves (n = 40 per study phase) were randomly assigned to either of two treatment groups, i.e. a vaccinated or a placebo group. calves in the vaccinated group received an inactivated bacterin containing a j-5 mutant strain of e. coli via ... | 2004 | 15542194 |
| viability of milk neutrophils and severity of bovine coliform mastitis. | to study the host-pathogen interactions during escherichia coli mastitis, we first determined whether e. coli infection would change blood and milk polymorphonuclear neutrophil (pmn) chemiluminescence (cl) and viability. we then hypothesized that when e. coli invade the mammary gland, the viable pmn in milk would efficiently phagocytose and destroy e. coli before establishment of infection. we observed that the phagocytosis-dependent and independent cl were closely linked to pmn viability and we ... | 2004 | 15545377 |
| genetic diversity of escherichia coli recovered from the oral cavity of beef cattle and their relatedness to faecal e. coli. | to determine the genetic diversity of generic escherichia coli recovered from the oral cavities of beef cattle and their relatedness to e. coli isolated from the faeces of cattle during pasture grazing and feedlot finishing. | 2004 | 15548305 |
| nmr structure of the bovine prion protein isolated from healthy calf brains. | nmr structures of recombinant prion proteins from various species expressed in escherichia coli have been solved during the past years, but the fundamental question of the relevancy of these data relative to the naturally occurring forms of the prion protein has not been directly addressed. here, we present a comparison of the cellular form of the bovine prion protein isolated and purified from healthy calf brains without use of detergents, so that it contains the two carbohydrate moieties and t ... | 2004 | 15568016 |
| characterization of lactobacillus coryniformis dsm 20001t surface protein cpf mediating coaggregation with and aggregation among pathogens. | phenotypic characterization of aggregation phenotypes of lactobacillus coryniformis revealed that strain dsm 20001t coaggregated with escherichia coli k88, campylobacter coli, and campylobacter jejuni but not with other human pathogens. in addition, cells of these pathogens aggregated in the presence of the spent culture supernatant (scs) of strain dsm 20001t. cells of e. coli k88 remained viable in the coaggregates and aggregates for up to 24 h. both coaggregation and aggregation (co/aggregatio ... | 2004 | 15574903 |
| association of escherichia coli o157:h7 with houseflies on a cattle farm. | the ecology of escherichia coli o157:h7 is not well understood. the aims of this study were to determine the prevalence of and characterize e. coli o157:h7 associated with houseflies (hf). musca domestica l. hf (n = 3,440) were collected from two sites on a cattle farm over a 4-month period and processed individually for e. coli o157:h7 isolation and quantification. the prevalence of e. coli o157:h7 was 2.9 and 1.4% in hf collected from feed bunks and a cattle feed storage shed, respectively. e. ... | 2004 | 15574966 |
| a comparison of aflp and eric-pcr analyses for discriminating escherichia coli from cattle, pig and human sources. | amplified fragment length polymorphism (aflp) and enterobacterial repetitive intergenic consensus polymerase chain reaction (eric-pcr) genomic fingerprinting assays were compared for their ability to differentiate escherichia coli isolates obtained from various host sources, and with respect to their pathogenicity. one hundred and ten verotoxigenic, enterotoxigenic and non-pathogenic e. coli isolates obtained from cattle, humans and pigs were used in this study. the aflp assay was shown to be hi ... | 2004 | 19712352 |
| cloning and expression of recombinant mpb70 protein antigen from mycobacterium bovis bcg for diagnosis of tuberculosis. | in a search for developing new skin test reagents, mpb70 protein antigen was a candidate antigen for the diagnosis of bovine tuberculosis. first m. bovis bcg genomic dna was extracted purified and the mpb70 gene was amplified by pcr. the gene was then ligated to an expression vector, pqe. after transformation of the expression e. coil m15 host strain with the pqe plasmid, the expression was induced using 10 mm of iptg. two bands were seen in the sds-page analysis the 44 and 50 kda represents the ... | 2004 | 16734114 |
| interactive inhibition of meat spoilage and pathogenic bacteria by lysozyme, nisin and edta in the presence of nitrite and sodium chloride at 24 degrees c. | to develop a nisin- and lysozyme-based antimicrobial treatment for use with processed ham and bologna, in vitro experiments were conducted to determine whether inhibition enhancing interactions occur between the antimicrobials lysozyme, chrisin (a commercial nisin preparation), edta, nacl and nano(2). inhibitory interactions were observed between a number of agents when used against specific pathogenic and spoilage bacteria. the observed interactions included lysozyme with edta (enterococcus fae ... | 2003 | 12423927 |
| antimicrobial resistance and resistance gene determinants in clinical escherichia coli from different animal species in switzerland. | antimicrobial susceptibility testing was performed on a total of 581 clinical escherichia coli isolates from diarrhea and edema disease in pigs, from acute mastitis in dairy cattle, from urinary tract infections in dogs and cats, and from septicemia in laying hens collected in switzerland between 1999 and 2001. among the 16 antimicrobial agents tested, resistance was most frequent for sulfonamides, tetracycline, and streptomycin. isolates from swine presented significantly more resistance than t ... | 2003 | 12441233 |
| in vitro growth of mastitis-inducing escherichia coli in milk and milk fractions of dairy cows. | the outcome of e. coli mastitis in cows ranges from mild to severe in individual animals. this study explored the hypothesis that milk from individual cows differs in its growth medium properties for e. coli, and whether possible variation could be related to specific milk constituents. to mimic the early phase of intramammary e. coli infection, a low inoculum size and a short incubation period were used. cell-reduced, cell- and fat-free (skim) and cell- and fat-free and protein-reduced (whey) f ... | 2003 | 12458162 |
| human serum amyloid a3 peptide enhances intestinal muc3 expression and inhibits epec adherence. | we previously determined that the n-terminal region of bovine mammary-associated serum amyloid a3 (m-saa3) increased intestinal mucin muc3 levels in ht29 human intestinal cells by approximately 2.5-fold, relative to untreated cells. this study shows that the human m-saa3 n-terminal peptide further enhances muc3 transcript levels by approximately 4.3-fold in these cells (p<0.02), implicating a species-specific interaction. furthermore, immunofluorescence and immunoblot analysis using a muc3-speci ... | 2003 | 12504116 |
| the conserved tflk motif of mammary-associated serum amyloid a3 is responsible for up-regulation of intestinal muc3 mucin expression in vitro. | in various mammalian species, an isoform of serum amyloid a is secreted at high concentrations into colostrum. a conserved four-amino-acid motif (tflk) is contained within the first eight n-terminal amino acid residues of this mammary-associated serum amyloid a isoform 3 (m-saa3). peptides derived from the bovine n-terminal amino acid sequence of m-saa3 were produced and added to cell culture medium of ht29 cells to study the effects on intestinal mucin gene expression. ht29 cells were grown to ... | 2003 | 12508093 |
| microbial contamination on beef and sheep carcases in south australia. | a total of 523 chilled beef and lamb carcases were sampled from four abattoirs and 13 very small plants (vsps) in south australia during march 2002 in order to develop a microbiological profile of meat produced for domestic consumption within the state. aerobic viable counts (avcs) and escherichia coli counts were obtained from samples taken by sponge-sampling the muscle-adipose tissue at sites designated for each species in the microbiological guidelines to the australian standard for hygienic ... | 2003 | 12485752 |
| evaluation of frequent milkout for treatment of cows with experimentally induced escherichia coil mastitis. | to evaluate the effect of frequent milkout (fmo) on the outcome of experimentally induced escherichia coli mastitis in cows. | 2003 | 12523483 |
| comparison of shiga toxin production by hemolytic-uremic syndrome-associated and bovine-associated shiga toxin-producing escherichia coli isolates. | there is considerable diversity among shiga toxin (stx)-producing escherichia coli (stec) bacteria, and only a subset of these organisms are thought to be human pathogens. the characteristics that distinguish stec bacteria that give rise to human disease are not well understood. stxs, the principal virulence determinants of stec, are thought to account for hemolytic-uremic syndrome (hus), a severe clinical consequence of stec infection. stxs are typically bacteriophage encoded, and their product ... | 2003 | 12571029 |
| geographical variation in ribotype profiles of escherichia coli isolates from humans, swine, poultry, beef, and dairy cattle in florida. | waters impacted by fecal pollution can exact high risks to human health and can result in financial losses due to closures of water systems used for recreation and for harvesting seafood. identifying the sources of fecal pollution in water is paramount in assessing the potential human health risks involved as well as in assessing necessary remedial action. recently, various researchers have used the ribotyping method to identify sources of bacterial indicators (escherichia coli and enterococci) ... | 2003 | 12571033 |
| image analysis method for evaluation of specific and non-specific hand contamination. | to evaluate a quantifying image analysis method for assessing the degree of hand contamination and efficacy of hand washing procedures. | 2003 | 12588557 |
| thermal and urea-induced unfolding of the marginally stable lac repressor dna-binding domain: a model system for analysis of solute effects on protein processes. | thermodynamic and structural evidence indicates that the dna binding domains of lac repressor (laci) exhibit significant conformational adaptability in operator binding, and that the marginally stable helix-turn-helix (hth) recognition element is greatly stabilized by operator binding. here we use circular dichroism at 222 nm to quantify the thermodynamics of the urea- and thermally induced unfolding of the marginally stable laci hth. van't hoff analysis of the two-state unfolding data, highly a ... | 2003 | 12590610 |
| opsonic activity of serum and whey from cows immunized with the ferric citrate receptor. | the effects of immunizing dairy cows with the ferric citrate receptor, feca, on the opsonic activity of serum and whey were measured in a phagocytosis assay. fifteen cows were assigned to five blocks of three cows based on date of expected parturition. cows within a block were randomly assigned to one of three treatments: 1) feca immunization, 2) immunization with a commercially available escherichia coli j5 bacterin, and 3) unimmunized controls. cows were challenged at approximately 21 dim by i ... | 2003 | 12613859 |
| comparison of ribotyping and repetitive extragenic palindromic-pcr for identification of fecal escherichia coli from humans and animals. | this report compares the performances of two popular genotypic methods used for tracking the sources of fecal pollution in water, ribotyping and repetitive extragenic palindromic-pcr (rep-pcr). the rep-pcr was more accurate, reproducible, and efficient in associating dna fingerprints of fecal escherichia coli with human and animal hosts of origin. | 2003 | 12620878 |
| comparison of methods for dna isolation from food samples for detection of shiga toxin-producing escherichia coli by real-time pcr. | in this study, food samples were intentionally contaminated with escherichia coli o157:h7, and then dna was isolated by using four commercial kits. the isolated dna samples were compared by using real-time pcr detection of the shiga toxin genes. the four kits tested worked similarly. | 2003 | 12620880 |
| an improved enrichment broth for isolation of escherichia coli o157, with specific reference to starved cells, from radish sprouts. | an enrichment broth was developed for the efficient isolation of escherichia coli o157 from radish sprouts. the broth was buffered peptone water containing 0.5% sodium thioglycolate (stg-bpw), which was designed to allow growth of e. coli o157 in starved and unstarved states. however, this medium suppressed the growth of non-carbohydrate-fermenting obligate aerobes whose colonial appearance on sorbitol macconkey agar containing cefixime and tellurite (ct-smac) resembled that of e. coli o157. bot ... | 2003 | 12620883 |
| sympathoadrenal and immune system activation during the periparturient period and their association with bovine coliform mastitis. a review. | increased incidence of clinical mastitis in high-yielding cows during early lactation has been attributed to a depressed functional capacity of the immune system. sympathoadrenal factors are known to play an important role in modulating the host susceptibility and resistance to infectious diseases. of primary importance in combating acute intramammary infections are polymorphonuclear leukocytes (pmn), as they represent one of the early lines of immunological defense. the release of stress hormon ... | 2003 | 12670012 |
| verotoxin-producing escherichia coli in spain: prevalence, serotypes, and virulence genes of o157:h7 and non-o157 vtec in ruminants, raw beef products, and humans. | in spain, as in many other countries, verotoxin-producing escherichia coli (vtec) strains have been frequently isolated from cattle, sheep, and foods. vtec strains have caused seven outbreaks in spain (six caused by e. coli o157:h7 and one by e. coli o111:h- [nonmotile]) in recent years. an analysis of the serotypes indicated serological diversity. among the strains isolated from humans, serotypes o26:h11, o111:h-, and o157:h7 were found to be more prevalent. the most frequently detected serotyp ... | 2003 | 12671177 |
| [cloning and expression of a novel ubiquitin fusion gene uba256]. | spodoptera litura nucleopolyhedrovirus (spltmnpv) uba256 gene is the only ub-gp37 fusion gene in the genome of insect viruses. with the specific primers designed for uba256 gene that was reported recently, the coding regions of uba256, n-terminal ubiquitin and c-terminal gp37 that lacking the signal sequence, were amplified from spltmnpv genomic dna by pcr. the uba256 coding region was expressed using the expression vector pbv220, and a band of 38 kd was detected with western blot analysis, indi ... | 2003 | 12673391 |
| presence and characterization of extraintestinal pathogenic escherichia coli virulence genes in f165-positive e. coli strains isolated from diseased calves and pigs. | the virulence genotype profile and presence of a pathogenicity island(s) (pai) were studied in 18 strains of f165-positive escherichia coli originally isolated from diseased calves or piglets. on the basis of their adhesion phenotypes and genotypes, these extraintestinal pathogenic strains were classified into three groups. the f165 fimbrial complex consists of at least two serologically and genetically distinct fimbriae: f165(1) and f165(2). f165(1) is encoded by the foo operon (pap-like), and ... | 2003 | 12682117 |
| vaccination strategies for reducing clinical severity of coliform mastitis. | brief history and extensive published field efficacy data of the two rough ("r") bacterial mutants utilized in commercial preparations of the core antigen bacterins escherichia coli o111:b4 (strain j5) and salmonella typhimurium re-17 are summarized. particular dosage schedules and routes of administration of coliform mastitis bacterins are compared for their associated ecacy. practical concerns in employing a coliform mastitis vaccination program are discussed. characteristics of farms using co ... | 2003 | 12682942 |
| evidence for a cd14- and serum-independent pathway in the induction of endotoxin-tolerance in human monocytes and thp-1 monocytic cells. | lipopolysaccharide (lps) stimulation of macrophages or monocytes is believed to occur via a serum- and cd14-dependent signaling pathway via toll-like receptor 4 (tlr4). we sought to determine whether serum and/or cd14 are required for lps to induce the endotoxin-tolerant state in human monocytes. lps treatments were performed in the presence or absence of an anti-cd14 monoclonal antibody and with or without fetal bovine serum. endotoxin tolerance was assessed after an 18-h exposure (pretreatment ... | 2003 | 12688542 |
| molecular cloning and heterologous expression in e. coli of cytochrome p45017alpha. comparison of structural and functional properties of substrate-specific cytochromes p450 from different species. | to elucidate the nature of substrate specificity and intrinsic mechanism of hydroxylation of steroids, in the present work we carried out molecular cloning and heterologous expression of cdna for three new forms of cytochrome p45017alpha from species of the bovidae family (sheep, goat, and bison), which catalyze 17alpha-hydroxylation of both progesterone (p4) or pregnenolone (p5) and 17,20-lyase reaction resulting in cleavage of side chain with formation of c(19)-steroids. recombinant cytochrome ... | 2003 | 12693981 |
| shiga toxin-producing escherichia coli (stec) isolated from healthy dairy cattle in southern brazil. | over a period of 1 year, the production of verotoxin was investigated in 1127 escherichia coli isolated from 243 dairy cattle from 60 small farms in southern brazil. vero cell assay was used to detect toxins in culture supernatants from e. coli isolated from bovine feces. shiga toxin-producing e. coli (stec) detection rates were 95% (57 of 60) for farms and 49% (119 of 243) for cattle. prevalence of stec-positive cattle in the farms ranged from 0 to 100%. ninety-six percent (315 of 327) of the s ... | 2003 | 12695042 |
| 2-methyl-3-hydroxybutyryl-coa dehydrogenase deficiency is caused by mutations in the hadh2 gene. | 2-methyl-3-hydroxybutyryl-coa dehydrogenase (mhbd) deficiency is a novel inborn error of isoleucine degradation. in this article, we report the elucidation of the molecular basis of mhbd deficiency. to this end, we purified the enzyme from bovine liver. maldi-tof mass spectrometry analysis revealed that the purified protein was identical to bovine 3-hydroxyacyl-coa dehydrogenase type ii. the human homolog of this bovine enzyme is a short-chain 3-hydroxyacyl-coa dehydrogenase, also known as the " ... | 2003 | 12696021 |
| thermal inactivation of escherichia coli o157:h7 in ground beef supplemented with sodium lactate. | a study was conducted to investigate the antimicrobial effect of sodium lactate (nal) (0, 1.5, 3.0, and 4.5%) on the survival of escherichia coli o157:h7 in 93% lean ground beef. samples inoculated with a mixture of four strains of e. coli o157:h7 (10(7) to 10(8) cfu/g) were subjected to immersion heating in a water bath stabilized at 55, 57.5, 60, 62.5, or 65 degrees c. results of statistical analysis indicated that the heating temperature was the only factor affecting the decimal reduction tim ... | 2003 | 12696693 |
| forage feeding to reduce preharvest escherichia coli populations in cattle, a review. | although escherichia coli are commensal organisms that reside within the host gut, some pathogenic strains of e. coli can cause hemorrhagic colitis in humans. the most notable enterohemorrhagic e. coli (ehec) strain is o157:h7. cattle are asymptomatic natural reservoirs of e. coli o157:h7, and it has been reported that as many as 30% of all cattle are carriers of this pathogen, and in some circumstances this can be as high as 80%. feedlot and high-producing dairy cattle are fed large grain ratio ... | 2003 | 12703622 |
| influence of agitation, inoculum density, ph, and strain on the growth parameters of escherichia coli o157:h7--relevance to risk assessment. | foods may differ in at least two key variables from broth culture systems typically used to measure growth kinetics of enteropathogens: initial population density of the pathogen and agitation of the culture. the present study used nine escherichia coli o157:h7 strains isolated from beef and associated with human illness. initial kinetic experiments with one e. coli o157:h7 strain in brain-heart infusion (bhi) broth at ph 5.5 were performed in a 2 x 2 x 3 factorial design, testing the effects of ... | 2003 | 12706036 |
| risk factors associated with faecal shedding of verocytotoxin-producing escherichia coli o157 in eight known-infected danish dairy herds. | a risk-factor study was performed in eight dairy herds found to excrete verocytotoxin-producing escherichia coli (vtec) o157 in a former prevalence study. associations between excretion of vtec o157 and management factors such as housing and feeding were analysed in a generalised linear mixed model. the animals were stratified in three age groups and sampled four times during 1 year. the risk of excreting vtec o157 was higher among weaned calves than non-weaned calves. among the calves aged 1-4 ... | 2003 | 12706052 |