Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID 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 |
| concentrations of alpha-tocopherol after intramammary infusion of escherichia coli or lipopolysaccharide. | fifteen holstein cows were used in a trial involving intramammary challenge to determine the effects of acute clinical mastitis on the concentrations of alpha-tocopherol in milk and plasma and the concentrations of neutrophils in milk and blood. cows were assigned to one of three experimental groups challenged by intramammary infusion of lipopolysaccharide, escherichia coli, or sterile phosphate-buffered saline. all quarters infused with lipopolysaccharide or e. coli were diagnosed with clinical ... | 1997 | 9406075 |
| a community outbreak of vero cytotoxin producing escherichia coli o157 infection linked to a small farm dairy. | a community outbreak of infection with vero cytotoxin producing escherichia coli o157 (vtec 0157) occurred in a small area of north west england in 1996. an outbreak control team was established to investigate the outbreak and implement control measures. nine people developed symptomatic infections with vtec o157, and a further three were found to be excreting the bacteria. all were infected with the same genotype of vtec o157. three children under 5 years of age and one adult were admitted to h ... | 1997 | 9447786 |
| conjugal transfer of plasmids and antibiotic resistance among escherichia coli isolated from animals in a rural area in sarawak (malaysia). | thirty-six strains of escherichia coli isolated from animals in bario, a remote area in sarawak, malaysia, were examined for presence of plasmid dna and their susceptibility to nine antimicrobial agents. of the total 36 isolates, five bovine and six canine isolates were found to contain plasmid dna ranging in sizes from 2.6 to 70 kilobases. all were susceptible to chloramphenicol, erythromycin, gentamicin, nalidixic acid and neomycin but resistance to ampicillin (47%), erythromycin (19%), strept ... | 1997 | 12452600 |
| distribution and sources of microbial contamination on beef carcasses. | three beef dressing lines of different capacity (160, 440 and 800 head d(-1)) were investigated with respect to contamination associated with carcass/hide and carcass/faeces contacts, the distribution of microbial contamination on carcasses and the antimicrobial efficacy of cold water carcass washes. swab samples were taken from up to 17 sites for determination of aerobic plate counts at 37 degrees c (apc 37 degrees c) and escherichia coli enumeration using the petrifilm procedure. the three bee ... | 1997 | 12455892 |
| escherichia coli o157:h7 in healthy dairy cows. | faecal samples were taken from 371 cows originating from 55 dairy farms and slaughtered at one slaughterhouse; tonsils were taken from 215 of these animals. escherichia coli 0157:h7 was found in the faeces of only two animals and was not found in any tonsils. the farm supplying the first positive cow detected at the slaughterhouse was visited 3 months later and 160 animals (80 cows and 80 heifers) were tested by rectal swabs; e. coli 0157:h7 was not isolated. | 1997 | 16031948 |
| effect of natural infection with minor pathogens on susceptibility to natural infection with major pathogens in the bovine mammary gland. | to evaluate the effect of natural udder infection with minor pathogens on subsequent natural infection with major pathogens. | 1997 | 8989490 |
| ultrastructural and immunocytochemical study of the pulmonary intravascular macrophages of escherichia coli lipopolysaccharide-treated sheep. | pulmonary intravascular macrophages (pims) of sheep, cattle, goats, and horses have a novel heparin-sensitive chain of globules, called a surface coat, on their plasma membrane. the globules are arranged at a distance of 32-39 nm from the plasma membrane of pims. intravascular nonbiological tracer particles complex with these globules prior to their endocytosis by the pims. | 1997 | 9026001 |
| studies on the development and use of a monoclonal sandwich elisa for the detection of verotoxic escherichia coli in animal faeces. | a sandwich elisa using monoclonal antibodies to escherichia coli verocytotoxins 1 and 2 for capture and detection was developed for detection of verocytotoxin-producing escherichia coli (vtec) in animal faeces. for optimal toxin detection, the faeces were cultured in macconkey broth before subculture on to trypticase soy agar containing mitomycin c. it was possible to detect between 10 and 10(3) vti-producing and 1 to 10 vt2-producing e coli/g faeces, and overall the sensitivity and specificity ... | 1997 | 9042694 |
| anaplasma marginale major surface protein 3 is encoded by a polymorphic, multigene family. | the immunodominant surface protein, msp3, is structurally and antigenically polymorphic among strains of anaplasma marginale. in this study we show that a polymorphic multigene family is at least partially responsible for the variation seen in msp3. the a. marginale msp3 gene msp3-12 was cloned and expressed in escherichia coli. with msp3-12 as a probe, multiple, partially homologous gene copies were identified in the genomes of three a. marginale strains. these copies were widely distributed th ... | 1997 | 8975906 |
| human insulin-like growth factor i (igf-i) produced in the mammary glands of transgenic rabbits: yield, receptor binding, mitogenic activity, and effects on igf-binding proteins. | insulin-like growth factor i (igf-i) has acute insulin-like metabolic effects and long-term anabolic actions offering a range of important therapeutic applications. to evaluate a system for large-scale production of this peptide in the mammary glands of transgenic livestock, we generated transgenic rabbits carrying fusion genes in which a synthetic dna coding for human igf-i (higf-i) was placed under the transcriptional control of regulatory elements isolated from the bovine alpha s1-casein (alp ... | 1997 | 8977418 |
| experimental escherichia coli o157:h7 carriage in calves. | nine weaned calves (6 to 8 weeks of age) were given 10(10) cfu of a five-strain mixture of enterohemorrhagic escherichia coli o157:h7 by oral-gastric intubation. after an initial brief period of pyrexia in three calves and transient mild diarrhea in five calves, calves were clinically normal throughout the 13- to 27-day study. the population of e. coli o157:h7 in the faces decreased dramatically in all calves during the first 2 weeks after inoculation. thereafter, small populations of e. coli o1 ... | 1997 | 8979335 |
| reticuloendothelial system uptake of infused 125i-trypsin in newborn and adult rats. | previous studies have demonstrated enhanced intestinal trypsin uptake and decreased liver clearance of trypsin in newborn rats compared to adults. in order to examine the effectiveness of the reticuloendothelial system (res) in clearing trypsin, bovine trypsin (1.25 mg/100 g body weight) plus trace 125i-trypsin were injected into the portal vein of 2-week-old (n = 57) and adult (n = 44) control rats or following res stimulation using intraperitoneally injected lipopolysaccharide or res suppressi ... | 1997 | 9057994 |
| the proton-translocating nadh-quinone oxidoreductase (ndh-1) of thermophilic bacterium thermus thermophilus hb-8. complete dna sequence of the gene cluster and thermostable properties of the expressed nqo2 subunit. | the genes encoding the proton-translocating nadh-quinone oxidoreductase (ndh-1) of a thermophilic bacterium thermus thermophilus hb-8 were cloned and sequenced. they constitute a cluster that is composed of 14 structural genes and contains no unidentified reading frames. all of the 14 structural genes, which are designated nqo1-14, encode subunits homologous to those of paracoccus denitrificans ndh-1, respectively, and are arranged in the same order as other bacterial ndh-1 genes. t. thermophilu ... | 1997 | 9020134 |
| identification of a c-terminal binding site for g-protein betagamma-subunits in phosducin-like protein. | phosducin-like protein (phlp) has recently been identified as a ubiquitous inhibitor of g-protein betagamma-subunit (g betagamma)-mediated signaling, with an affinity about 5-fold lower than that of phosducin. the g betagamma binding site of phosducin has been suggested to be contained in its n-terminus. a region corresponding to this n-terminus is lacking in phlp, suggesting that phlp must utilize a different mode of g betagamma binding. to map the g betagamma binding site in phlp, a series of ... | 1997 | 9013896 |
| kinetics of excision of purine lesions from dna by escherichia coli fpg protein. | the kinetics of excision of damaged purine bases from oxidatively damaged dna by escherichia coli fpg protein were investigated. dna substrates, prepared by treatment with h2o2/fe(iii)-edta or by gamma-irradiation under n2o or air, were incubated with fpg protein, followed by precipitation of dna. precipitated dna and supernatant fractions were analyzed by gas chromatography/isotope-dilution mass spectrometry. kinetic studies revealed efficient excision of 8-hydroxyguanine (8-oh-gua), 2,6-diamin ... | 1997 | 9016584 |
| structure-function studies of the adenylate cyclase toxin of bordetella pertussis and the leukotoxin of pasteurella haemolytica by heterologous c protein activation and construction of hybrid proteins. | the adenylate cyclase toxin (cyaa) from bordetella pertussis and the leukotoxin (lkta) from pasteurella haemolytica are members of the rtx (stands for repeats in toxin) family of cytolytic toxins. they have pore-forming activity and share significant amino acid homology but show marked differences in biological activity. cyaa is an invasive adenylate cyclase and a weak hemolysin which is active on a wide range of mammalian cells. lkta is a cytolytic protein with a high target cell specificity an ... | 1997 | 9006045 |
| casein kinase ii phosphorylates bovine papillomavirus type 1 e1 in vitro at a conserved motif. | the e1 protein of bovine papillomavirus type 1 (bpv-1) is a phosphoprotein which specifically binds and unwinds the virus replication origin by atp-dependent helicase activity. the el protein has been shown to be multiply phosphorylated in vivo, although the sites of modification are incompletely mapped. examination of the predicted amino acid sequence of all available e1 proteins revealed strong conservation between amino acids 25 and 60 of a motif consisting of a serine residue followed by a s ... | 1997 | 9010301 |
| ribotyping of fusobacterium necrophorum strains isolated from bovine and ovine hepatic abscesses. | a microbiological study was made of 100 strains of fusobacterium necrophorum isolated from hepatic abscesses in bovine and ovine herds. differences between the biological activity and ribotypes within the two f. necrophorum subspecies were studied. conventional methods identified 89 isolates as f. necrophorum subsp. necrophorum and 11 as f. necrophorum subsp. funduliforme. for ribotyping, 50 strains (35 f.n. subsp. necrophorum, 11 f.n. subsp. funduliforme and 4 reference strains) were digested w ... | 1998 | 16887645 |
| cloning, sequencing and expression of a cdna encoding bovine pancreatic deoxyribonuclease i in escherichia coli: purification and characterization of the recombinant enzyme. | the bovine pancreatic (bp-) dnase i gene has been cloned from bp-cdna and expressed in e. coli. a polynucleotide sequence of 1295 base pairs was deduced from clones of the cdna. the sequence showed an open reading frame which can be translated as a 282-amino acid polypeptide, including a hydrophobic signal peptide and the polypeptide of bp-dnase i. an expression plasmid was constructed by inserting into the vector pet-15b, a cdna fragment coding for bp-dnase i ligated with a hexanucleotide codin ... | 1998 | 9469931 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| lactoferricin of bovine origin is more active than lactoferricins of human, murine and caprine origin. | the antimicrobial peptide lactoferricin is generated by gastric pepsin cleavage of lactoferrin. we have examined the antimicrobial activity of lactoferricins derived from lactoferrin of human, murine, caprine and bovine origin with minimal inhibitory concentration (mic) and minimal bactericidal concentration (mbc) against e. coli atcc 25922 and s. aureus atcc 25923. we found that lactoferricin of bovine origin (lf-cin b) was the most efficacious of the lactoferricins tested. by comparing the lin ... | 1998 | 10066056 |
| 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 |
| 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 |
| synthesis and serological characterization of l-glycero-alpha-d-manno-heptopyranose-containing di- and tri-saccharides of the non-reducing terminus of the escherichia coli k-12 lps core oligosaccharide. | synthesis of the title trisaccharide was accomplished by sugar chain extension starting from the non-reducing terminus: coupling of glcp nac with ld-hepp, then adding glcp-oall. an alternative route started from the reducing end: coupling of ld-hepp with glcp-oall, then addition of glcp nac. in the synthesis of the title disaccharide a modification of the first approach was employed. the allyl glycosides were coupled with cysteamine, activated with thiophosgene and conjugated to bovine serum alb ... | 1998 | 10230038 |
| 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 |
| recombinant production and purification of novel antisense antimicrobial peptide in escherichia coli. | a fusion protein was genetically engineered that contains an antimicrobial peptide, designated p2, at its carboxy terminus and bovine prochymosin at its amino terminus. bovine prochymosin was chosen as the fusion partner because of its complete insolubility in escherichia coli, a property utilized to protect the cells from the toxic effects of the antimicrobial peptide. this fusion protein was purified by centrifugation as an insoluble inclusion body. a methionine linker between prochymosin and ... | 1998 | 10099178 |
| 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 |
| production, crystallization and diffraction to atomic resolution of an antibody fv specific for the blood-group a oligosaccharide antigen. | the histoblood-group abo carbohydrate antigens are well known as important factors in blood transfusions, but they can also act as receptors for infectious agents and have been implicated in susceptibility to certain carcinomas. a single-chain variable-domain antigen-binding fragment (scfv) gene based on the known sequence of an anti-blood-group-a monoclonal antibody (ac1001) has been synthesized and expressed in escherichia coli. the purified scfv preparation existed primarily in the monomeric ... | 1998 | 10089537 |
| sequence and context dependence of ef-hand loop dynamics. an 15n relaxation study of a calcium-binding site mutant of calbindin d9k. | the influence of amino acid sequence and structural context on the backbone dynamics of ef-hand calcium-binding loops was investigated using 15n spin relaxation measurements on the calcium-free state of the calbindin d9k mutant (a14d+a15delta+p20delta+n21g+p43m), in which the n-terminal pseudo-ef-hand loop, characteristic of s100 proteins, was engineered so as to conform with the c-terminal consensus ef-hand loop. the results were compared to a previous study of the apo state of the wild-type-li ... | 1998 | 9485409 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |