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an investigation of the quality of meat sold in lesotho.since the closure of the lesotho abattoir in 2003, only imported meat can be legally sold. however, it was estimated in 2007 that 80% of the meat sold at butcheries comes from informal slaughter. the aim of this study was to investigate the situation. the number and location of informal butcheries in lesotho (n = 143) were recorded and mapped using geographical information systems. observations (photographs) of informal slaughter indicated a lack of hygiene, unskilled slaughtermen and illegal di ...200920458865
antimicrobial activities and cellular responses to natural silicate clays and derivatives modified by cationic alkylamine salts.nanometer-scale silicate platelet (nsp) materials were previously developed by increasing the interlayer space and exfoliation of layered silicate clays such as montmorillonite and synthetic fluorinated mica by the process of polyamine exfoliation. in this study, the antibacterial activity and cytotoxicity of these nanometer-scale silicate clays were evaluated. the derivatives of nsp (nsp-s) which were modified by c18-fatty amine salts via ionic exchange association exhibited the highest antibac ...200920356127
influence of farming methods on microbiological contamination and prevalence of resistance to antimicrobial drugs in isolates from beef.the presence of escherichia coli, staphylococcus aureus, listeria monocytogenes and salmonella spp. was determined in 75 samples of conventional beef and in 75 samples of organic beef. all samples came from cattle slaughtered and processed in the same slaughterhouse and quartering room. a total of 180 e. coli, 180 s. aureus and 98 l. monocytogenes strains were analyzed by an agar disk diffusion assay for their resistance to 11 antimicrobials, for the case of e. coli and s. aureus, or 9 antimicro ...200920416735
transmission and quantification of verocytotoxin-producing escherichia coli o157 in dairy cattle and calves.data from a field study of 14 months duration in a naturally colonized dairy herd and data from an experiment with calves were used to quantify transmission of verocytotoxin-producing escherichia coli (vtec o157) in cattle. for the latter, two groups of 10 calves were randomly assigned and put out in one of two pastures. from each group, five animals were experimentally inoculated with 109 c.f.u. o157 vtec and, considered infectious, put back in their group. each of the susceptible contact calve ...200918346284
characterization of specific egg yolk immunoglobulin (igy) against mastitis-causing escherichia coli.the objective of this study was to estimate the in vitro activity of egg yolk immunoglobulin (igy) against mastitis-causing escherichia coli. specific igy was produced by hens immunized with formaldehyde killed e. coli o111 in long-standing immunization response (titer > or =6400 for 100 days) and was isolated from yolks with a purity of 86% by water dilution, salt precipitations and ultrafiltration. enzyme-linked immunosorbent assay (elisa) indicated the produced igy specifically targeted e. co ...200818255238
risk assessment for escherichia coli o157:h7 in marketed unpasteurized milk in selected east african countries.we carried out a study to assess the risk associated with the presence of shiga toxigenic escherichia coli (stec) in informally marketed unpasteurized milk in urban east africa. data for the risk models were obtained from on-going and recently completed studies in kenya and uganda. inputs for the model were complemented with data from published literature in similar populations. a fault-tree scenario pathway and modular process risk model approach were used for exposure assessment. hazard charac ...200818326173
ehaa is a novel autotransporter protein of enterohemorrhagic escherichia coli o157:h7 that contributes to adhesion and biofilm formation.autotransporter (at) proteins have been identified in many gram-negative pathogens and are unique in that their primary sequence is sufficient to direct their transport across the bacterial membrane system. where characterized they are uniformly associated with virulence. using conserved at motifs as a search tool, four putative at proteins were identified in the enterohemorrhagic escherichia coli o157:h7 edl933 genome. the genes encoding these proteins (z0402/ehaa, z0469/ehab, z3487/ehac and z3 ...200818237301
role of alphaphe-291 residue in the phosphate-binding subdomain of catalytic sites of escherichia coli atp synthase.the role of alphaphe-291 residue in phosphate binding by escherichia coli f1f0-atp synthase was examined. x-ray structures of bovine mitochondrial enzyme suggest that this residue resides in close proximity to the conserved betar246 residue. herein, we show that mutations alphaf291d and alphaf291e in e. coli reduce the atpase activity of f1f0 membranes by 350-fold. yet, significant oxidative phosphorylation activity is retained. in contrast to wild-type, atpase activities of mutants were not inh ...200818242162
antimicrobial activity of sodium hypochlorite and chlorhexidine by two different tests.the aim of this study was to evaluate the antimicrobial capacity of sodium hypochlorite (1% and 5%) and chlorhexidine (0.12%, 0.5% and 1%) with or without the addition of organic material (bovine serum albumin, bsa) against some bacterial samples (staphylococcus aureus, enterococcus faecalis, escherichia coli, porphyromonas gingivalis and fusobacterium nucleatum) using two activity tests (contact and diffusion agar tests). in the contact test (first model), bacterial samples were kept in contact ...200818352899
the role of starvation on escherichia coli adhesion and transport in saturated porous media.the influence of bacterial starvation on cell transport has been examined using two escherichia coli isolates: one from human (hu) and one from dairy cattle (dc). to better understand the fate of starved bacteria, experiments were conducted in a packed bed column using cells that had been incubating at room temperature without nutrients for 6, 12, and 18h, as well as cells, which had not been starved (referred to as time zero). complimentary cell characterization techniques were conducted to eva ...200818037467
influence of processed grains on fecal ph, starch concentration, and shedding of escherichia coli o157 in feedlot cattle.manipulation of cattle diets has been proposed as a possible preharvest control measure for escherichia coli o157. altering hindgut fermentation through diet changes may be a means to reduce fecal shedding of e. coli o157. in exp. 1, the objective was to determine whether fecal shedding of e. coli o157 was related to fecal starch concentration. beginning on d 20, and every week thereafter until d 61, steers in 54 pens (6 to 7 steers per pen) were sampled (n = 122) by fecal collection and rectoan ...200818042815
activatable shiga toxin 2d (stx2d) in stec strains isolated from cattle and sheep at slaughter.shiga toxin producing escherichia coli (stec) harbouring the stx(2d-activatable) gene and expressing the mucus- and elastase-activatable phenotype have been associated with severe outcomes of human disease. however, there is limited data available on the occurrence of such strains in livestock reservoirs. in this study, we analyzed 11 stec strains isolated from healthy cattle and sheep at slaughter that were originally detected to contain the stx(2c) allele, for the presence of the stx(2d-activa ...200818417300
the toll-like receptor-4 (tlr-4) pathway and its possible role in the pathogenesis of escherichia coli mastitis in dairy cattle.mastitis is one of the most costly production diseases in the dairy industry that is caused by a wide array of microorganisms. in this review, we focus on the gram-negative escherichia coli infections that often occur at periods when the innate immune defence mechanisms are impaired (i.e., parturition through the first 60 days of lactation). there is substantial evidence demonstrating that at these periods, the expected influx of polymorphonuclear neutrophil leukocytes (pmn) into the mammary gla ...200818073092
effects of exogenous melatonin and tryptophan on fecal shedding of e. coli o157:h7 in cattle.fecal prevalence of escherichia coli o157 in ruminants is highest in the summer decreasing to very low levels in the winter. we hypothesize that this seasonal variation is a result of physiological responses within the host animal to changing day-length. to determine the effects of melatonin (mel) on fecal shedding of e. coli o157:h7 in cattle, eight crossbred beef steers identified as shedding e. coli o157:h7, were allotted to treatment: control or mel (0.5 mg/kg body weight (bw); 1x) administe ...200817874261
bovine tlr2 and tlr4 properly transduce signals from staphylococcus aureus and e. coli, but s. aureus fails to both activate nf-kappab in mammary epithelial cells and to quickly induce tnfalpha and interleukin-8 (cxcl8) expression in the udder.staphylococcus aureus, but not e. coli pathogens frequently cause subclinical, chronic infections of the mammary gland. we examined here, if inadequate activation of the bovine tlr2 and tlr4 pathogen receptors by ligands derived from s. aureus pathogens might contribute to molecular mechanisms underpinning the escape strategies from mammary immune defence of this pathogen. we show that infections with live e. coli, but not s. aureus pathogens induce strongly il-8 and tnfalpha gene expression in ...200817936907
antimicrobial properties of milkfat globule membrane fractions.milkfat globule membranes (mfgms) were prepared from bovine cream according to standard procedures. these membranes and peptide hydrolysates, which were generated by proteolysis with immobilized digestive enzymes, were screened for antibacterial activity against escherichia coli o157:h7, listeria monocytogenes, salmonella enterica typhimurium, pseudomonas fluorescens, bacillus cereus, lactobacillus acidophilus, and lactobacillus gasseri. assays were first performed on beef heart infusion (bhi) p ...200818236672
antibiotic resistance of commensal escherichia coli of food-producing animals from three vojvodinian farms, serbia.commensal bacteria of food-producing animals are considered an important reservoir of antibiotic resistance. the aim of this study was to determine the current prevalence of resistance to 18 different antibiotics in animal commensal escherichia coli isolated from food-producing animals from three different farms with specific modes of antimicrobial use. a very high prevalence of resistance was found to tetracycline, a moderate level to streptomycin, ampicillin, cefalothin and nalidixic acid and ...200818162377
high-throughput identification of t-lymphocyte antigens from anaplasma marginale expressed using in vitro transcription and translation.the ability to rapidly screen a complex pathogen proteome for proteins that elicit recall t-lymphocyte responses from immune individuals would accelerate vaccine development. an outer membrane fraction of the rickettsial pathogen anaplasma marginale induces protective immunity against infection and disease in cattle. we have used this immunization model to evaluate high-throughput screening of proteins expressed by in vitro transcription and translation (ivtt) for recognition by memory cd4(+) t- ...200818243240
assessment of phenotypic and genotypic diversity of escherichia coli shed by healthy lactating dairy cattle.a study was conducted to assess the diversity among fecal escherichia coli from healthy lactating cattle. e. coli (n = 100) isolates from 10 healthy lactating dairy cows of a pennsylvania dairy herd were examined for phenotypic and genotypic characteristics. results revealed 26, 58, 10, and 6 e. coli isolates belonged to phylogenetic groups a, b1, b2, and d respectively. overall, 63 serotypes, nine antibiotic resistance profiles, and 65 pulsed-field gel electrophoresis (pfge) profiles were obser ...200818260814
escherichia coli o157:h7 and non-o157 shiga toxin-producing e. coli in healthy cattle, sheep and swine herds in northern spain.three-hundred and forty-five herds (17 swine, 122 dairy sheep, 124 beef and 82 dairy cattle) were investigated for prevalence of shiga toxin-producing escherichia coli (stec). rectal faecal samples were selectively enriched and then examined by immunodetection techniques (immunomagnetic separation with anti-e. coli o157 dynabeads, immunomagnetic cell separation (ims) and automated enzyme-linked fluorescent immunoassay using vidas) and polymerase chain reaction (pcr) (rfbe and flic genes) to asse ...200818234025
a comparison of equine and bovine sera as sources of lipopolysaccharide-binding protein activity in equine monocytes incubated with lipopolysaccharide.lipopolysaccharide-binding protein (lbp) is an acute phase protein that binds the lipid a moiety of lipopolysaccharide (lps) and transfers lps monomers to soluble cd14 in plasma or membrane bound cd14 on mononuclear phagocytes. the result of these interactions is activation of the tlr4 receptor complex, and the synthesis and release of inflammatory mediators. inclusion of lbp in cellular assays increases the sensitivity of cells expressing cd14 to lps. therefore, the objectives of this study wer ...200818023485
identification of ground beef-derived fatty acid inhibitors of autoinducer-2-based cell signaling.autoinducer-2 (ai-2) molecules are used by several microorganisms to modulate various processes, including bioluminescence, biofilm formation, and virulence expression. certain food matrices, including ground beef extracts, possess compounds capable of inhibiting ai-2 activity. in the present study, we identified and characterized these ai-2 inhibitors from ground beef extract using hexane solvent extraction and gas chromatography. gas chromatographic analysis revealed the presence of several fa ...200818236673
the methionine sulfoxide reductases: catalysis and substrate specificities.oxidation of met residues in proteins leads to the formation of methionine sulfoxides (metso). methionine sulfoxide reductases (msr) are ubiquitous enzymes, which catalyze the reduction of the sulfoxide function of the oxidized methionine residues. in vivo, the role of msrs is described as essential in protecting cells against oxidative damages and to play a role in infection of cells by pathogenic bacteria. there exist two structurally-unrelated classes of msrs, called msra and msrb, with oppos ...200818302927
effect of skimmed milk and its fractions on the inactivation of escherichia coli k12 by high hydrostatic pressure treatment.we investigated the effects of skimmed milk and its protein fractions (casein, whey, globulin, and albumin) on the injury and inactivation of escherichia coli k-12 by high hydrostatic pressure (hhp) treatment. the protective effect of skimmed milk on hhp-mediated inactivation and injury of e. coli increased with increases in the skimmed milk concentration. however, protein fractions derived from skimmed milk did not exhibit this protective effect. microscopy analysis by dapi/pi staining indicate ...200818313781
efficacy of the bovine antimicrobial peptide indolicidin combined with piperacillin/tazobactam in experimental rat models of polymicrobial peritonitis.to investigate the efficacy of piperacillin/tazobactam combined with indolicidin in the prevention of lethality in two rat models of polymicrobial peritonitis.200818090372
development and evaluation of a recombinant antigen-based elisa for serodiagnosis of cattle lungworm.an optimised enzyme-linked immunosorbent assay (elisa) for the detection of dictyocaulus viviparous-specific antibodies was developed and evaluated following the testing of various microtitration plates and anti-bovine ig-conjugates. based on recombinant major sperm protein (msp) expressed as a glutathione-s-transferase (gst) fusion protein in escherichia coli, sera collected from 112 cattle experimentally infected with d. viviparus, from 129 helminth-naïve calves, 8 calves experimentally infect ...200818155839
characterization of inducible stx2-positive escherichia coli o157:h7/h7- strains isolated from cattle in france.to quantify the variability of the shiga toxin 2 (stx2) production by a panel of stx2-positive escherichia coli o157:h7/h7- isolates from healthy cattle before and after induction with enrofloxacin.200818194247
microbiological quality of retail cheeses made from raw, thermized or pasteurized milk in the uk.two studies of retail fresh, ripened and semi-hard cheeses made from raw, thermized or pasteurized milk were undertaken in the uk during 2004 and 2005 to determine the microbiological quality of these products. using microbiological criteria in european commission recommendations 2004/24/ec and 2005/175/ec, 2% of both raw, thermized (37/1819 samples) and pasteurized (51/2618 samples) milk cheeses were of unsatisfactory quality. raw or thermized milk cheeses were of unsatisfactory quality due to ...200818206773
the concerted action of lactoferrin and bacteriophages in the clearance of bacteria in sublethally infected mice.both lactoferrin (lf) and bacteriophages are potent antibacterial agents. lf is contained in the secretory fluids of mammals and bacteriophages are specific bacterial viruses.200818268472
endothelial cell apoptosis induced by bacteria-activated platelets requires caspase-8 and -9 and generation of reactive oxygen species.a common feature of severe sepsis is vascular inflammation and damage to the endothelium. because platelets can be directly activated by bacteria and endotoxin, these cells may play an important role in determining the outcome of sepsis. for example, inhibiting platelet interactions with the endothelium has been shown to attenuate endothelial cell damage and improve survival during sepsis. although not entirely understood, the interactions between bacteria-activated platelets and the endothelium ...200818278187
role of antioxidants and trace elements in health and immunity of transition dairy cows.a number of antioxidants and trace minerals have important roles in immune function and may affect health in transition dairy cows. vitamin e and beta-carotene are important cellular antioxidants. selenium (se) is involved in the antioxidant system via its role in the enzyme glutathione peroxidase. inadequate dietary vitamin e or se decreases neutrophil function during the perpariturient period. supplementation of vitamin e and/or se has reduced the incidence of mastitis and retained placenta, a ...200818325801
identification of immune genes and proteins involved in the response of bovine mammary tissue to staphylococcus aureus infection.mastitis in dairy cattle results from infection of mammary tissue by a range of micro-organisms but principally coliform bacteria and gram positive bacteria such as staphylococcus aureus. the former species are often acquired by environmental contamination while s. aureus is particularly problematic due to its resistance to antibiotic treatments and ability to reside within mammary tissue in a chronic, subclinical state. the transcriptional responses within bovine mammary epithelial tissue subje ...200818513449
ribosomal rna-based analysis of the bacterial flora from the conjunctivae of cattle with bovine keratoconjunctivitis (bkc).bovine keratoconjunctivitis (bkc), colloquially referred to as 'pinkeye', is a disease affecting cattle worldwide; it costs cattle producers millions of dollars in economic loss annually. while moraxella spp. are the primary etiologic agent of pinkeye, surveys of flora from the conjunctivae of livestock from around the world have indicated that a variety of bacterial commensals occupy this niche. we used molecular biology-based methods to determine the composition of bacterial flora in the conju ...200818513895
detection and determinants of escherichia coil o157:h7 in alberta feedlot pens immediately prior to slaughter.food safety risks due to escherichia coli o157:h7 may be affected by variability in prevalence in or on live cattle at slaughter. our objectives were to assess the prevalence and risk factors associated with e. coli o157:h7 in feedlot pens immediately prior to slaughter, and assess relationships among methods of monitoring the e. coli o157:h7 status of pre-harvest pens. we studied 84 pens containing a total of nearly 27,000 head of cattle in commercial feedlots in alberta during 2003 and 2004. s ...200818505184
acceptor substrate specificity of udp-gal: glcnac-r beta1,3-galactosyltransferase (wbbd) from escherichia coli o7:k1.most of the glycosyltransferases involved in o antigen biosynthesis have not yet been characterized. we recently demonstrated that the wbbd gene of the o7 lipopolysaccharide biosynthesis cluster in e. coli strain vw187 (o7:k1) encodes wbbd, a udp-gal: glcnacalpha-pyrophosphate-lipid beta1,3-gal-transferase (ec 2.4.1., accession number aac27537) that transfers the second sugar moiety in the assembly of the o7 repeating unit. the enzyme utilizes undecaprenol-pyrophosphate-glcnac as a natural accep ...200818536883
crystallization and preliminary x-ray diffraction analysis of the carbohydrate-recognizing domain (vp8*) of bovine rotavirus strain ncdv.the infectivity of rotavirus is dramatically enhanced by proteolytic cleavage of its outer layer vp4 spike protein into two functional domains, vp8* and vp5*. the carbohydrate-recognizing domain vp8* is proposed to bind sialic acid-containing host cell-surface glycans and this is followed by a series of subsequent virus-cell interactions. live attenuated human and bovine rotavirus vaccine candidates for the prevention of gastroenteritis have been derived from bovine rotavirus strain ncdv. the nc ...200818540062
phylogenetic background of attaching and effacing escherichia coli isolates from animals.detection and distribution of eae gene in forty-four attaching and effacing escherichia coli (aeec) strains of animal origin were investigated. association of distinct intimin alleles with phylogenetic background were assessed among strains in comparison with different serogroups. phylogenetic analysis showed that 31 ehec/eae+ stec strains belong to groups a, b1 and e, 13 epec strains segregated in b1 and b2. moreover, group a possessed the eae gamma2/theta type, group b1 the eae beta1, eae kapp ...200818509740
validation of a commercial process for inactivation of escherichia coli o157:h7, salmonella typhimurium, and listeria monocytogenes on the surface of whole muscle beef jerky.we validated the lethality of three time and temperature regimens for commercial processing of whole muscle beef jerky. a total of ca. 8.9 log cfu per strip of multiple-strain cocktails of escherichia coli o157:h7, salmonella typhimurium, or listeria monocytogenes were separately applied onto the surface of beef strips that were treated as follows: (i) inoculated but not marinated or (ii) inoculated and then marinated. a total of three beef strips for each treatment in each of three trials were ...200818522024
uterine diseases in cattle after parturition.bacterial contamination of the uterine lumen is common in cattle after parturition, often leading to infection and uterine disease. clinical disease can be diagnosed and scored by examination of the vaginal mucus, which reflects the presence of pathogenic bacteria such as escherichia coli and arcanobacterium pyogenes. viruses may also cause uterine disease and bovine herpesvirus 4 (bohv-4) is tropic for endometrial cells, causing a rapid cytopathic effect. the elimination of pathogens by the inn ...200818329302
preparation, characterization and refolding in vitro of a recombinant human cyclophilin a mutant: effect of a single pro/ser substitution on cyclophilin a structure and properties.a recombinant cyclophilin a (cypa) mutant, which carries a serine instead of proline at sequence 16, was prepared for structural and functional assessment for human cypa. soluble expression of the recombinant cypa mutant in e. coli was obtained under 30 degrees c, 180 rpm culture condition after being induced by iptg. ion exchange chromatography was used to purify the cypa mutant in a single step, and a high activity recovery of target protein with a high purity was achieved. peptide fragments p ...200818333624
thionin thi2.1 from arabidopsis thaliana expressed in endothelial cells shows antibacterial, antifungal and cytotoxic activity.thionins are plant antimicrobial peptides with antibacterial and antifungal activities. thionin thi2.1 cdna from arabidopsis thaliana was expressed in bve-e6e7 bovine endothelial cell line and its activity was evaluated against escherichia coli, staphylococcus aureus, candida albicans and different mammal cell lines. total protein (2.5 microg) from conditioned medium (cm) of clone ec-thi2.1 inhibited the growth of e. coli, s. aureus (>90%) and c. albicans strains (>80%) in relation to the cm fro ...200818563581
functional role of polyhydroxy compounds on protein structure and thermal stability studied by circular dichroism spectroscopy.polyhydroxy compounds such as cyclitols, acyclic polyols and sugars are produced by a wide variety of organisms under stressful conditions in order to protect macromolecular structure. plants undergoing abiotic stresses like heat and dehydration accumulate enormous amounts of polyhydroxy compounds (up to 400 mm) in their cellular tissues. not only do they serve as osmoprotectants ("compatible solutes"), they also protect membrane structure and preserve enzymatic activity. to gain further insight ...200818343146
incidence rate of clinical mastitis on canadian dairy farms.no nationwide studies of the incidence rate of clinical mastitis (ircm) have been conducted in canada. because the ircm and distribution of mastitis-causing bacteria may show substantial geographic variation, the primary objective of this study was to determine regional pathogen-specific ircm on canadian dairy farms. additionally, the association of pathogen-specific ircm with bulk milk somatic cell count (bmscc) and barn type were determined. in total, 106 dairy farms in 10 provinces of canada ...200818349229
environmental prevention of human disease from verocytotoxin-producing escherichia coli.verocytotoxin-producing escherichia coli (vtec) haemolytic uraemic syndrome (hus) is an important cause of mortality and renal failure worldwide. for those patients who need medical attention, no treatment aside from supportive care has proven effective for this disease. this has prompted a broader look at environmental prevention, with a particular emphasis on the transmission of bacteria from animal carriers to human beings. here, we review animal- and meat-handling strategies to reduce the bu ...200818356186
anaplasma marginale major surface protein 1a directs cell surface display of tick bm95 immunogenic peptides on escherichia coli.the surface display of heterologous proteins on live escherichia coli using anchoring motifs from outer membranes proteins has impacted on many areas of biochemistry, molecular biology and biotechnology. the anaplasma marginale major surface protein 1a (msp1a) contains n-terminal surface-exposed repeated peptides (28-289 amino acids) that are involved in pathogen interaction with host cell receptors and is surface-displayed when the recombinant protein is expressed in e. coli. therefore, it was ...200818582976
escherichia coli o157:h7 colonization in cattle following systemic and mucosal immunization with purified h7 flagellin.escherichia coli o157:h7 is an important pathogen of humans. cattle are most frequently identified as the primary source of infection, and therefore, reduction in e. coli o157:h7 prevalence in cattle by vaccination represents an attractive strategy for reducing the incidence of human disease. h7 flagella have been implicated in intestinal-epithelial colonization of e. coli o157:h7 and may represent a useful target for vaccination. in this study, calves were immunized either systemically with h7 ...200818362130
transfer of immunoglobulins through the mammary endothelium and epithelium and in the local lymph node of cows during the initial response after intramammary challenge with e. coli endotoxin.the first hours after antigen stimulation, interactions occur influencing the outcome of the immunological reaction. immunoglobulins originate in blood and/or are locally synthesized. the transfer of ig isotypes (igs) in the udder has been studied previously but without the possibility to distinguish between the endothelium and the epithelium. the purpose of this study was to map the ig transfer through each barrier, separately, and ig transfer in the local lymph nodes of the bovine udder during ...200818597683
biocompatibility index of antiseptic agents by parallel assessment of antimicrobial activity and cellular cytotoxicity.to assess the suitability of an antiseptic agent, both the microbicidal activity and the cytotoxic effect must be taken into consideration to derive biocompatible antibacterial agents.200818364400
duplex real-time pcr assays for rapid detection of virulence genes in e. coli isolated from post-weaning pigs and calves with diarrhoea.duplex real-time pcr assays were used as modules to cover partially automated detection of 12 genes encoding adhesins, enterotoxins and shiga toxins in faecal e. coli isolates. for this a total of 194 e. coli isolates from pigs suffering from post-weaning diarrhoea (pwd), including 65 isolates with haemolytic activity, and 83 isolates from calves with diarrhoea were examined. data obtained by pcr were compared with o-typing and with haemolytic activity as indirect virulence markers. e. coli o-ty ...200818605375
evolution, expression and effectiveness in a cluster of novel bovine beta-defensins.the anti-microbial peptides beta-defensins constitute a large family of innate immune effector molecules, conserved across a wide species range. in this paper, we describe a systematic search of the sequenced bovine genome to characterise this extensive gene family in bos taurus, providing an insight into the pattern of conservation of beta-defensin genes between species. we have sequenced a sub-set of these newly discovered bovine beta-defensin genes and also report expression data for these ge ...200818369613
prevalence of vtec o157 in dairy and veal herds and risk factors for veal herds.the aim of this study was to determine the herd prevalence of veal and dairy herds and to identify risk factors for vtec o157 positive veal herds. the study was based on monitoring data from november 1996 through july 2005 of 1051 dairy herds and 930 veal herds. the herd level prevalence (95% ci) was 8.0% (6.4-9.6) for dairy herds and 12.6% (10.5-14.7) for veal herds. within the population of veal herds, a prevalence of 39.8% (33.9-45.6) was found for pink veal herds (n = 269) and 1.5% (0.7-2.8) ...200818614252
electron microscopic analysis of dairy microbes inactivated by ultrasound.ultrasonication is a non-thermal method of food preservation that has the advantage of inactivating microbes in food without causing the common side-effects associated with conventional heat treatments, such as nutrient and flavour loss. the aim of this study was to evaluate the use of ultrasound as an alternative to heat pasteurisation and to assess cell damage using transmission electron microscopy (tem). three spoilage microbes, previously isolated from pasteurised milk, were used as "test" m ...200818406653
beta-hydroxybutyrate abrogates formation of bovine neutrophil extracellular traps and bactericidal activity against mammary pathogenic escherichia coli.escherichia coli is an important bacterial species isolated from bovine mastitis. the rate of neutrophil recruitment into the mammary gland and their bactericidal activity largely affect the severity and outcome of the disease. ketosis is a common metabolic disease, and affected dairy cows are known to have increased risk for mastitis and other infectious conditions. the disease is associated with high blood and milk levels of beta-hydroxybutyrate (bhba), previously shown to negatively affect ne ...200818411287
inhibitory effects of bovine lactoferrin and lactoferricin b on enterobacter sakazakii.the susceptibility of enterobacter sakazakii, a food-borne pathogen, to several metal-bound forms of bovine lactoferrin (lf), pepsin-hydrolyzed lf (lf-hyd), and lf-derived peptide lactoferricin b (lfcin b) was tested. mic and mbc testing revealed that 4 strains of e. sakazakii show susceptibility to apo- and cu-lf, lf-hyd, and lfcin b, but not to fe-lf, similarly to escherichia coli. a growth curve test indicated that e. sakazakii was inhibited in a dose-dependent manner by apo-lf at 0.5 to 8 mg ...200818432114
three-dimensional structure of respiratory complex i from escherichia coli in ice in the presence of nucleotides.complex i (nadh:ubiquinone oxidoreductase) is the largest protein complex of bacterial and mitochondrial respiratory chains. the first three-dimensional structure of bacterial complex i in vitrified ice was determined by electron cryo-microscopy and single particle analysis. the structure of the escherichia coli enzyme incubated with either nad(+) (as a reference) or nadh was calculated to 35 and 39 a resolution, respectively. the x-ray structure of the peripheral arm of thermus thermophilus com ...200818433710
comparison of fecal versus rectoanal mucosal swab sampling for detecting escherichia coli o157:h7 in experimentally inoculated cattle used in assessing bacteriophage as a mitigation strategy.this study was conducted to compare fecal grab (fec) and rectoanal mucosal swab (rams) techniques as sampling methods for surveillance of escherichia coli o157:h7 in conjunction with administration of a mitigation therapy. the study was nested within a larger experiment that investigated bacteriophage as a preharvest strategy for controlling e. coli o157:h7 in feedlot steers. samples (fec and rams) were collected from 16 of the 32 feedlot steers (control and oral bacteriophage treatment; n = 8) ...200818468021
inactivation of escherichia coli o157:h7 in ground beef by single-cycle and multiple-cycle high-pressure treatments.the effect of single- and multiple-cycle high-pressure treatments on the survival of escherichia coli cect 4972, a strain belonging to the o157:h7 serotype, in ground beef was investigated. beef patties were inoculated with 10(7) cfu/g e. coli o157:h7, and held at 4 degrees c for 20 h before high-pressure treatments. reduction of the e. coli o157:h7 population by single-cycle treatments at 400 mpa and 12 degrees c ranged from 0.82 log cfu/g for a 1-min cycle to 4.39 log cfu/g for a 20-min cycle. ...200818468038
antimicrobial susceptibility of enteric bacteria recovered from feedlot cattle administered chlortetracycline in feed.to evaluate administration of chlortetracycline in feed of cattle as a method to select for tetracycline resistance among enteric bacteria in feedlot settings.200818672961
epidemiological survey on escherichia coli o157 in chongqing and three-gorge reservoir areas of china.prevalence, presence of virulence and adherence associated genes, genetic diversity, biochemical characteristics, and antibiotic susceptibility were determined for escherichia coli o157 isolated over 4 months in chongqing city and three-gorge reservoir areas. 11 isolates of e. coli o157 were isolated from 1504 samples and 7 of them are o157:h7 and 4 are o157:h? all o157:h7 isolates had eaea, ehxa, espa and tccp genes, but did not have stx1 and stx2. all o157:h? isolates did not have stx1, stx2, ...200818481192
assembly of a membrane receptor complex: roles of the uroplakin ii prosequence in regulating uroplakin bacterial receptor oligomerization.the apical surface of the mammalian urothelium is almost completely covered by two-dimensional protein crystals (known as urothelial plaques) of hexagonally packed 16 nm particles consisting of two up (uroplakin) heterodimers, i.e. ups ia/ii and ib/iii pairs. ups are functionally important as they contribute to the urothelial permeability barrier function, and upia may serve as the receptor for the uropathogenic escherichia coli that causes over 90% of urinary tract infections. we study here how ...200818481938
were there any "misassignments" among iron-sulfur clusters n4, n5 and n6b in nadh-quinone oxidoreductase (complex i)?nadh-quinone oxidoreductase (complex i) in bovine heart mitochondria has a molecular weight of approximately 1 million da composed of 45 distinct subunits. it is the largest energy transducing complex so far known. bacterial complex i is simpler and smaller, but the essential redox components and the basic mechanisms of electron and proton translocation are the same. over the past three decades, ohnishi et al. have pursued extensive epr studies near liquid helium temperatures and characterized m ...200818486592
genotypic characterization and prevalence of virulence factors among canadian escherichia coli o157:h7 strains.in this study, the association between genotypic and selected phenotypic characteristics was examined in a collection of canadian escherichia coli o157:h7 strains isolated from humans and cattle in the provinces of alberta, ontario, saskatchewan, and quebec. in a subset of 69 strains selected on the basis of specific phage types (pts), a strong correlation between the lineage-specific polymorphism assay (lspa6) genotype and pt was observed with all strains of pts 4, 14, 21, 31, 33, and 87 belong ...200818487402
synergistic effect between different milk-derived peptides and proteins.antimicrobial peptides derived from food proteins constitute a new field in the combined use of antimicrobial agents in food. the best examples of milk-derived peptides are those constituted by bovine lactoferricin [lactoferrin f(17-41)] (lfcin-b) and bovine alpha(s2)-casein f(183-207). the aim of this work was to study if the antimicrobial activity of a natural compound employed in food preservation, nisin, could be enhanced by combination with the aforementioned milk-derived peptides. furtherm ...200818487640
staphylococcus aureus and escherichia coli cause deviating expression profiles of cytokines and lactoferrin messenger ribonucleic acid in mammary epithelial cells.pathogens invading the mammary gland cause a complex signaling network that activates the early immune defense and leads to an outcome of inflammation symptoms. to examine the importance of mammary epithelial cells in these regulations and interactions resulting in a pathogen-related course of mastitis, we characterized the mrna expression profile of key molecules of the innate immune system by quantitative real-time pcr. mammary gland epithelial cells isolated on d 42 of lactation from 28 first ...200818487644
comparison of holstein and jersey innate immune responses to escherichia coli intramammary infection.mastitis is one of the most prevalent diseases in cattle and remains among the most costly diseases to the dairy industry. various surveys have indicated a greater prevalence of and risk for mastitis in holstein cows than in jersey cows. the innate immune system comprises the immediate host defense mechanisms that respond to infection, and differences in the magnitude and rapidity of this response are known to influence susceptibility to and clearance of infectious pathogens. the reported differ ...200818487645
pathogen-specific effects of quantitative trait loci affecting clinical mastitis and somatic cell count in danish holstein cattle.the aim of this study was to investigate whether quantitative trait loci (qtl) affecting the risk of clinical mastitis (cm) and qtl affecting somatic cell score (scs) exhibit pathogen-specific effects on the incidence of mastitis. bacteriological data on mastitis pathogens were used to investigate pathogen specificity of qtl affecting treatments of mastitis in first parity (cm1), second parity (cm2), and third parity (cm3), and qtl affecting scs. the 5 most common mastitis pathogens in the danis ...200818487673
selenoglutaredoxin as a glutathione peroxidase mimic.glutaredoxin (grx1) from escherichia coli is a monomeric, 85-amino-acid-long, disulfide-containing redox protein. a grx1 variant in which the redox-active disulfide was replaced with a selenocysteine (c11u/c14s) was prepared by native chemical ligation from three fragments as a potential mimic of the natural selenoenzyme glutathione peroxidase (gpx). selenoglutaredoxin, like the analogous c14s grx1 variant, shows weak peroxidase activity. the selenol provides a 30-fold advantage over the thiol, ...200818548475
colorimetric method for enzymatic screening assay of atp using fe(iii)-xylenol orange complex formation.in hygiene management, recently there has been a significant need for screening methods for microbial contamination by visual observation or with commonly used colorimetric apparatus. the amount of adenosine triphosphate (atp) can serve as the index of a microorganism. this paper describes the development of a colorimetric method for the assay of atp, using enzymatic cycling and fe(iii)-xylenol orange (xo) complex formation. the color characteristics of the fe(iii)-xo complexes, which show a dis ...200818726586
characterization of an escherichia coli o157:h7 o-antigen deletion mutant and effect of the deletion on bacterial persistence in the mouse intestine and colonization at the bovine terminal rectal mucosa.escherichia coli o157:h7 causes hemorrhagic colitis and the life-threatening hemolytic-uremic syndrome in humans and transiently colonizes healthy cattle at the terminal rectal mucosa. to investigate the role of the o antigen in persistence and colonization in the animal host, we generated an e. coli o157:h7 mutant defective in the synthesis of the lipopolysaccharide side chain (o antigen) by deletion of a putative perosamine synthetase gene (per) in the rfb cluster. the lack of o antigen was co ...200818552194
acute phase response in two consecutive experimentally induced e. coli intramammary infections in dairy cows.acute phase proteins haptoglobin (hp), serum amyloid a (saa) and lipopolysaccharide binding protein (lbp) have suggested to be suitable inflammatory markers for bovine mastitis. the aim of the study was to investigate acute phase markers along with clinical parameters in two consecutive intramammary challenges with escherichia coli and to evaluate the possible carry-over effect when same animals are used in an experimental model.200818554387
[microbiological studies of spiced beef burgers in tripoli city, libyan arab jamahiriya].we investigated the microbiological quality of uncooked and cooked spiced beef burger in restaurants and fast food places in tripoli city and surrounding areas. thus 151 samples (92 cooked and 59 uncooked) were analysed microbiologically. the results showed that all samples were highly contaminated with bacteria; 74.5%, 28.8%, 27.1% and 18.6% of the uncooked samples were contaminated with escherichia coli, aeromonas spp., staphylococcus aureus and e. coli o157:h7 respectively. additionally 11.9% ...200818557465
outbreak of escherichia coli o157:h7 associated with raw milk consumption in the pacific northwest.in late 2005, health officials in clark county, washington noted a higher than expected number of escherichia coli cases among residents and sought to identify a possible common source for infection. in order to identify risk factors, health officials conducted a retrospective cohort study and an environmental site investigation using pulsed-field gel electrophoresis (pfge) to identify and prevent future cases from occurring. several lines of evidence supported raw milk as the cause of infection ...200818564912
identification of a bovine mastitis escherichia coli subset.eleven escherichia coli isolates from clinical bovine mastitis cases (mastitic strains) and 11 from the cowshed environment (environmental strains) were compared, to determine if the former were a subset of the latter. the mastitic and environmental strains could not be distinguished according to o antigen and antibiotic sensitivity. all mastitic isolates showed significantly (p<0.0001) faster growth in milk and faster lactose fermentation than most (approximately 64%) environmental strains, but ...200818571344
expression and purification of the 26 kda periplasmic protein of brucella abortus: a reagent for the diagnosis of bovine brucellosis.development of a single diagnostic test for brucellosis in animals is the top priority of present-day research in the field. there is currently a battery of serological tests relying mainly on the use of lps (lipopolysaccharide) as an antigen, culminating in false positives due to serological cross-reactivity. other problems include difficulties in antigen production and the associated biohazard risk. this has prompted the need to develop an alternative antigen to replace lps. in the present stu ...200817685896
clinical and ultrasonographic findings, diagnosis and treatment of pyelonephritis in 17 cows.the goal of the present study was to describe the clinical, haematological and ultrasonographic findings and treatment of 17 cattle with pyelonephritis. fifteen cattle had an abnormal general condition, which varied in severity; five animals had signs of colic. the urine was brownish-red in 11 animals and cloudy in 13. clumps of purulent material were seen in the urine of nine animals and clots of blood in two. the specific gravity was lower than normal in 13 animals and ranged from 1.005 to 1.0 ...200817363303
survey of shiga toxigenic escherichia coli o157 and drug-resistant coliform bacteria from in-line milk filters on dairy farms in the czech republic.to determine the occurrence of shiga toxin-producing escherichia coli (stec) o157 and coliform bacteria isolates resistant to antimicrobial agents in dairy herds by examining milk filters and to analyse the influence of management factors and antibiotic use on antimicrobial resistance.200817953684
a comparison of antibiotic resistance integrons in cattle from separate beef meat production systems at slaughter.to compare antibiotic resistance integrons in cattle from three separate grass-fed, grain-fed and certified organic cattle production systems at slaughter.200817927756
combining targeted sampling and fluorometry to identify human fecal contamination in a freshwater creek.many bacterial source tracking (bst) methods are too expensive for most communities to afford. in an effort to develop an inexpensive method of detecting human sources of fecal contamination in a freshwater creek during baseflow and stormflow conditions, we combined targeted sampling with fluorometry. targeted sampling is a prelude to bst and finds sources of fecal contamination by continued sampling and resampling over ever-decreasing distances. fluorometry identifies human fecal contamination ...200817998611
xenorhabdus antibiotics: a comparative analysis and potential utility for controlling mastitis caused by bacteria.the role of antibiotics produced by bacterial symbionts of entomopathogenic nematodes is to suppress growth of microbes in the soil environment. these antibiotics are active against gram-positive and gram-negative bacteria, and were tested against mastitis isolates from dairy cows.200817976177
increased resistance of escherichia coli o157:h7 to electron beam following repetitive irradiation at sub-lethal doses.one way that food processors in the united states have been controlling food-borne pathogens in a non-thermal manner is the application of electron beam (e-beam) radiation. the development of an increased resistance of escherichia coli o157:h7 to various stressors such to ph, temperature, ionic strength, and antibiotics has been demonstrated. the objective of this study was to determine if the d(10)-value for e. coli o157:h7 (e. coli) in ground beef increases due to repetitive exposure to e-beam ...200818068251
effect of diet on the concentration of complex shiga toxin-producing escherichia coli and ehec virulence genes in bovine faeces, hide and carcass.an experiment was conducted to determine whether diets based on structural carbohydrate and/or simple sugars, as found in roughage and/or molasses-based diets, reduce the bovine faecal populations of shiga toxin-producing escherichia coli (stec) isolates containing the eaea and ehxa genes, referred to as complex stec (cstec), compared with typical high starch, grain-based feedlot diets. in addition, whether commercial lairage management practices promote or diminish any diet-induced responses on ...200818068254
interleukin-12 response to ncsrs2 immunization of balb/c mice against neospora caninum.the apicomplexan parasite neospora caninum can cause abortions and is recognized as an important causative agent responsible for economic and reproductive losses in the cattle industry. humoral immune response was investigated in balb/c mice by using recombinant ncsrs2 expressed in escherichia coli as polyhistidine-tagged fusion proteins. ncsrs2 is the major immunodominant tachyzoite surface antigen of n. caninum. separate groups of female balb/c mice were infected subcutaneously with (p) pbs, ( ...200820059851
a survey of enteric bacteria and protozoans in fresh bovine faeces on new zealand dairy farms.to determine the counts and/or prevalence in fresh bovine faeces of escherichia coli, enterococci, campylobacter, salmonella, shiga toxin-producing e. coli (stec), giardia and cryptosporidium, as inputs to numerical models designed to estimate microbial loadings on pasture grazed by cattle in new zealand.200819016977
all blood, no stool: enterohemorrhagic escherichia coli o157:h7 infection.enterohemorrhagic escherichia coli serotype o157:h7 is a pathotype of diarrheagenic e. coli that produces one or more shiga toxins, forms a characteristic histopathology described as attaching and effacing lesions, and possesses the large virulence plasmid po157. the bacterium is recognized worldwide, especially in developed countries, as an emerging food-borne bacterial pathogen, which causes disease in humans and in some animals. healthy cattle are the principal and natural reservoir of e. col ...200818716441
salmonella and escherichia coli o157:h7 contamination on hides and carcasses of cull cattle presented for slaughter in the united states: an evaluation of prevalence and bacterial loads by immunomagnetic separation and direct plating methods.the hide and carcass hygiene of cull cattle at slaughter in four geographically distant regions of the united states was examined from july 2005 to april 2006 by measuring the aerobic plate counts (apc) and the prevalences and loads of salmonella and escherichia coli o157:h7. the geometric mean log(10) apc cfu/100 cm(2) levels on hides and preevisceration and postintervention carcasses ranged from 6.17 to 8.19, 4.24 to 6.47, and 1.46 to 1.96, respectively, and were highest in the summer (p < 0.0 ...200818723661
factors associated with cross-contamination of hides of scottish cattle by escherichia coli o157.the putative source of hide contamination for 236 cattle in scotland followed from the farm through to slaughter was determined using phage and verocytotoxin type data. the majority of cattle (84%) were found to have subtypes of escherichia coli o157 on their hide that had not been found previously in any animal from the farm of origin, strongly suggesting that contamination occurred once animals had left the farm of origin. using logistic regression analysis, several variables and factors were ...200818723662
cloning, sequence, expression and characterization of human beta-mannosidase.beta-mannosidase (ec 3.2.1.25, manb) dissects the non-reducing end of n-linked mannose moieties of glycoproteins in eukaryotic cells. the human beta-mannosidase gene was amplified by rt-pcr, cloned and sequenced. the dna sequence was compared with reported human beta-mannosidase dna sequence and sixteen nucleotide differences were found. the deduced amino-acid sequence showed that seven codons coded the same amino acids and nine codons coded different amino acids with reference to nucleotide sub ...200818800177
the complete genome sequence of escherichia coli dh10b: insights into the biology of a laboratory workhorse.escherichia coli dh10b was designed for the propagation of large insert dna library clones. it is used extensively, taking advantage of properties such as high dna transformation efficiency and maintenance of large plasmids. the strain was constructed by serial genetic recombination steps, but the underlying sequence changes remained unverified. we report the complete genomic sequence of dh10b by using reads accumulated from the bovine sequencing project at baylor college of medicine and assembl ...200818245285
optimization of sterilization of escherichia coli in milk by surfactin and fengycin using a response surface method.in this paper, the sensitivity of escherichia coli to surfactin and fengycin was observed, and the optimization of the antimicrobial activity of surfactin and fengycin to e. coli in milk by a response surface methodology was studied. results showed that e. coli had high sensitivity to these antibiotics, whose minimal inhibitory concentrations were 15.625 microg.ml(-1) and 31.25 microg.ml(-1), respectively. the optimization result indicated that e. coli could be sterilized by 5 orders of magnitud ...200818058172
development of a conductometric phosphate biosensor based on tri-layer maltose phosphorylase composite films.a conductometric biosensor for phosphate detection was developed using maltose phosphorylase (mp) from recombinant escherichia coli immobilized on a planar interdigitated electrode by cross-linking with saturated glutaraldehyde (ga) vapour in the presence of bovine serum albumin (bsa). the process parameters for the fabrication of the mono-enzymatic sensor and various experimental variables such as the enzyme loading, time of immobilization in saturated ga vapour, working buffer solution and tem ...200818440365
new adhesin of enteroaggregative escherichia coli related to the afa/dr/aaf family.enteroaggregative escherichia coli (eaec) is an important cause of diarrhea worldwide. we analyzed 17 danish eaec strains, isolated in the course of a case control study, for phenotypic and genotypic properties. the strains belonged to at least 14 different serotypes. using pcr to investigate the prevalence of various putative virulence genes, we found that all but two strains were typical eaec, as they harbored all or part of the previously described aggr regulon. the majority of the strains ha ...200818443096
isolation and characterisation of two novel coliphages with high potential to control antibiotic-resistant pathogenic escherichia coli (ehec and epec).two newly isolated virulent coliphages (mvbs and mvss) showed ability to lyse (form plaque on) a high percentage of pathogenic escherichia coli strains of various serotypes and origins (292/310; 94.2%), whilst displaying low lytic (plaque-forming) capacity on non-pathogenic ecor strains (mvbs and mvss lysed 10/72 (13.9%) and 15/72 (20.8%) strains, respectively). in comparison, a higher percentage (196/310, 63.2%) of tested isolates exhibited resistance to a broad range of antibiotics. it was als ...200818082374
modulation of chemokine gene expression by shiga-toxin producing escherichia coli belonging to various origins and serotypes.infection with shiga-toxin producing escherichia coli (stec) may result in the development of the haemolytic-uremic syndrome (hus), the main cause of acute renal failure in children. while o157:h7 stec are associated with large outbreaks of hus, it is difficult to predict whether a non-o157:h7 isolate can be pathogenic for humans. the mucosal innate immune response plays a central role in the pathogenesis of hus; therefore, we compared the induction of il-8 and ccl20 in human colon epithelial ce ...200818248761
antimicrobial drug resistance of fecal escherichia coli and salmonella spp. isolates from united states dairy cows.antimicrobial resistance is a growing concern for public and animal health. threats to public health could come from the transfer of pathogens from animals to people via indirect contact such as through food or by direct contact with animals. in addition, concern has been raised for the potential transfer of resistance determinants from animals to humans through commensal bacterial flora such as escherichia coli. isolates of e. coli and salmonella spp. from dairy cows on farms in 21 states were ...200818260811
impact of transportation and lairage on hide contamination with escherichia coli o157 in finished beef cattle.transportation of cattle from the feedlot to the slaughter plant could influence hide contamination of escherichia coli o157. a study was initiated to investigate the influence of transportation and lairage on shedding and hide contamination of e. coli o157. fecal and hide samples were obtained from 40 pens of harvest-ready beef cattle at the feedlot prior to transport and again at the slaughter plant immediately after slaughter. potential risk factors for hide contamination at the feedlot, duri ...200818592735
immunogenicity of a chicken viral newcastle disease virus f gene-c3d fusion protein containing a chicken homologue of c3d.the gene fragment coding for arbor acres (aa) chicken c3d gene (chc3d) was cloned and expressed as a component of fusion proteins for its potential use as a vaccine for chickens and for in vitro experiments. this fragment of complement protein c3 (c3d) has been shown to strengthen b-cell responses when complexed with antigen. three potential vaccine constructs were engineered to contain two, four, and six copies of chc3d-p29 coding gene, which was linked to the f gene of newcastle disease virus ...200818788947
exposure to endotoxin during estrus alters the timing of ovulation and hormonal concentrations in cows.the effect of intramammary (imm) or intravenous (iv) administration of e. coli endotoxin (lps), at the onset of estrus, at the time of ovulation was examined. steroid and gonadotropin concentrations around ovulation were also determined. lactating holstein cows (n=33) were assigned to saline-controls (n=12) and treated with lps-iv (0.5 microg/kg; n=13) or lps-imm (10 microg; n=8). synchronized cows were observed continuously for estrus. lps (or saline) was injected within 30 min from the onset o ...200818602682
cloning of a gene fragment encoding chicken complement component c3d with expression and immunogenicity of newcastle disease virus f gene-c3d fusion protein.the gene fragment coding for the complement protein c3 (chc3d) from arbor acres (aa) chickens was cloned and expressed as a fusion protein for its application in the vaccine study of chicken, and for in vitro experiments. the chc3d fragment strengthened b-cell responses when complexed with antigen. three potential vaccine construct units were engineered to contain two, four and six copies of the chc3d-p29 coding gene linked to the f gene of newcastle disease virus, an economically important path ...200818798021
fate of chlorate present in cattle wastes and its impact on salmonella typhimurium and escherichia coli o157:h7.chlorate salts are being developed as a feed additive to reduce the numbers of pathogens in feedlot cattle. a series of studies was conducted to determine whether chlorate, at concentrations expected to be excreted in urine of dosed cattle, would also reduce the populations of pathogens in cattle wastes (a mixture of urine and feces) and to determine the fate of chlorate in cattle wastes. chlorate salts present in a urine-manure-soil mixture at 0, 17, 33, and 67 ppm had no significant effect on ...200818605736
map20, a microtubule-associated protein in the secondary cell walls of hybrid aspen, is a target of the cellulose synthesis inhibitor 2,6-dichlorobenzonitrile.we have identified a gene, denoted pttmap20, which is strongly up-regulated during secondary cell wall synthesis and tightly coregulated with the secondary wall-associated cesa genes in hybrid aspen (populus tremula x tremuloides). immunolocalization studies with affinity-purified antibodies specific for pttmap20 revealed that the protein is found in all cell types in developing xylem and that it is most abundant in cells forming secondary cell walls. this pttmap20 protein sequence contains a hi ...200818805954
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