Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| the function of recombinant cytochrome p450s in intact escherichia coli cells: the 17 alpha-hydroxylation of progesterone and pregnenolone by p450c17. | studies are reported showing that recombinant p450c17, coexpressed with rat nadph-p450 reductase or expressed as a fusion protein containing the domain of the p450 linked to the domain of nadph-p450 reductase, function effectively in intact escherichia coli cells. progesterone is rapidly hydroxylated by transformed e. coli cells at rates as rapid as 50 nmol of steroid hydroxylated/min/nmol of p450 at 37 degrees c. this rate measured in vivo equals or exceeds the best rates we have measured when ... | 1997 | 9056252 |
| 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 |
| efficacy of cefquinome for treatment of cows with mastitis experimentally induced using escherichia coli. | the efficacy of intramuscularly and intramammarily administered cefquinome was evaluated in experimental escherichia coli mastitis in dairy cows. forty-seven multiparous, israeli holstein cows in early lactation that produced at least 25 l/d of milk were used, and 400 to 750 cfu of e. coli were infused into two healthy quarters of each cow. cows were randomly assigned to one of the following treatment groups: 1) 75 mg of cefquinome administered intramammarily three times at 12-h intervals, 2) 75 ... | 1997 | 9058274 |
| cloning and expression of cdna for a newly identified isozyme of bovine liver 3-hydroxyacyl-coa dehydrogenase and its import into mitochondria. | cdna for a heretofore undescribed mitochondrial 3-hydroxyacyl-coa dehydrogenase, designated as the type ii enzyme with different molecular and catalytic properties, compared to those of the classical mitochondrial beta-oxidation enzyme (type i enzyme), was cloned from a bovine liver cdna library. nucleotide sequence of the cdna encoded 261 amino acids with a subunit molecular weight of 27,140. the deduced primary structure of the type ii enzyme showed no significant homology to the reported amin ... | 1997 | 9061028 |
| role of polyethyleneimine in the purification of recombinant human tumour necrosis factor beta. | the chromatographic behaviour of recombinant human tumour necrosis factor beta (rhtnf-beta) (pi approximately 9.0) during cation-exchange chromatography at ph 7.5 is investigated. without prior treatment of the escherichia coli cell extract with polyethyleneimine (pei), very little rhtnf-beta was bound to the column. however, upon addition of 5% pei (100 microliters ml-1) to the cell lysate, rhtnf-beta was shown to bind to cation-exchange columns normally. tnf-beta was readily precipitated from ... | 1997 | 9062987 |
| large-scale preparation and characterization of recombinant ovine placental lactogen. | to clone ovine placental lactogen (opl) cdna, total rna from sheep placental cotyledon was reverse transcribed and the single-stranded cdna was pcr-amplified with 5' and 3' primers containing, respectively, ncoi and psti sites. the opl cdna fragment amplified between these two primers extended from a(-1) to the natural stop codon. the pcr product was gel-purified and subcloned into a puc vector and the insert was sequenced on both strands, revealing several differences relative to the published ... | 1997 | 9071989 |
| nucleotide occupancy of f1-atpase catalytic sites under crystallization conditions. | using site-directed tryptophan fluorescence we studied nucleotide occupancy of the catalytic sites of escherichia coli f1-atpase, under conditions used previously for crystallization and x-ray structure analysis of the bovine mitochondrial enzyme [abrahams et al. (1994) nature 370, 621-628]. we found that only two of the three catalytic sites were filled in the e. coli enzyme under these conditions (250 microm mgamppnp plus 5 microm mgadp), consistent with what was reported in the bovine f1 x-ra ... | 1997 | 9074628 |
| a gene cluster closely related to type ii secretion pathway operons of gram-negative bacteria is located on the large plasmid of enterohemorrhagic escherichia coli o157 strains. | analysis of 14.162 kb of dna derived from plasmid po157 of enterohemorrhagic escherichia coli (ehec) o157:h7 strain edl933, extending in the 5' direction of the recently described ehec-hly operon, revealed 13 open reading frames (orf) which showed great similarities to genes of members of the type ii pathway secretion systems of gram-negative bacteria. we named the orfs etpc to etpo for ehec type ii secretion pathway. in addition, an is911-like insertion element was found to separate the etp gen ... | 1997 | 9084155 |
| characterization of human p33/41 (annexin iv), a ca2+ dependent carbohydrate-binding protein with monoclonal anti-annexin iv antibodies, as11 and as17. | p33/41 (annexin iv) is a member of the family of ca(2+)-dependent phospholipid binding proteins known as annexins. we previously described that bovine kidney p33/41 (annexin iv) has ca(2+)-dependent carbohydrate binding activity. in this study, we purified human p33/41 (annexin iv) from the ht29, human colon adenocarcinoma cell line, as well as the bovine kidney annexin by affinity chromatography. then, we prepared recombinant human p33/41 (annexin iv) expressed in escherichia coli. the apparent ... | 1997 | 9084877 |
| improved activity of a synthetic indolicidin analog. | a novel cationic peptide, cp-11, based on the structure of the bovine neutrophil peptide indolicidin, was designed to increase the number of positively charged residues, maintain the short length (13 amino acids), and enhance the amphipathicity relative to those of indolicidin. cp-11, and especially its carboxymethylated derivative, cp-11c, demonstrated improved activity against gram-negative bacteria and candida albicans, while it maintained the activity of indolicidin against staphylococci and ... | 1997 | 9087487 |
| the reversible antiport-uniport conversion of the phosphate carrier from yeast mitochondria depends on the presence of a single cysteine. | wild type and mutant phosphate carriers (pic) from saccharomyces cerevisiae mitochondria were expressed in escherichia coli as inclusion bodies, solubilized, purified, and optimally reconstituted into liposomal membranes. this pic can function as coupled antiport (pi-/pi- antiport and pi- net transport, i.e. pi-/oh- antiport) and uncoupled uniport (mercuric chloride-induced pi- efflux). the basic kinetic properties of these three transport modes were analyzed. the kinetic properties closely rese ... | 1997 | 9099701 |
| binding of transducin to light-activated rhodopsin prevents transducin interaction with the rod cgmp phosphodiesterase gamma-subunit. | in photoreceptor cells of vertebrates, the gtp-bound alpha-subunit of rod g-protein, transducin (g(t alpha)), interacts with the cgmp phosphodiesterase inhibitory gamma-subunit (pgamma) to activate the effector enzyme. the gdp-bound g(t alpha) can also bind the pgamma subunit, albeit with a lower affinity than g(t alpha)gtp. in this work, interactions between g(t alpha)gdp and pgamma or pgamma-24-45cys labeled with the fluorescent probe 3-(bromoacetyl)-7-(diethylamino)coumarin (pgammabc, pgamma- ... | 1997 | 9100013 |
| distribution and characterization of faecal verotoxin-producing escherichia coli (vtec) isolated from healthy cattle. | faecal swabs obtained from a random sample of 268 cows and 90 calves on 19 lugo farms were examined for verotoxin-producing escherichia coli (vtec). we found vtec on 95% of the farms. the prevalence rates of vtec infection in asymptomatic cows and calves were estimated to be 35 and 37%, respectively. the proportion of animals infected on each farm ranged from 0 to 100%. vtec strains isolated from healthy cattle belonged to 27 o serogroups; however, 57% (85 of 149) were of one of 8 serogroups (o2 ... | 1997 | 9100331 |
| hamburger-associated escherichia coli o157:h7 infection in las vegas: a hidden epidemic. | this study sought to determine whether a multistate fast food hamburger-associated outbreak of escherichia coli o157:h7 infection involved las vegas residents as well and, if so, why public health officials had not detected it. | 1997 | 9103093 |
| effect of inclusion body contaminants on the oxidative renaturation of hen egg white lysozyme. | the effect of typical contaminants in inclusion body preparations such as dna, ribosomal rna, phospholipids, lipopolysaccharides, and other proteins on renaturation rate and yield of hen egg white lysozyme was investigated. separate experiments were conducted in which known amounts of individual contaminants were added to test their effect on renaturation kinetics. on the basis of a simplified model for the kinetic competition between folding and aggregation, it was found that none of the above ... | 1997 | 9104038 |
| thermal destruction of escherichia coli o157:h7 in beef and chicken: determination of d- and z-values. | thermal inactivation of a four-strain mixture of e. coli o157:h7 was determined in 90% lean ground beef, and lean ground chicken. inoculated meat was packaged in bags which were completely immersed in a circulating water bath and held at 55, 57.5, 60, 62.5, and 65 degrees c for predetermined lengths of time. d-values, determined by linear regression, in beef were 21.13, 4.95, 3.17, 0.93 and 0.39 min, respectively (z = 6.0 degrees c). using a survival model for non-linear survival curves, d-value ... | 1997 | 9105932 |
| isolation and characterization of the cdna encoding bovine poly(adp-ribose) glycohydrolase. | the synthesis and rapid turnover of adp-ribose polymers is an immediate cellular response to dna damage. we report here the isolation and characterization of cdna encoding poly(adp-ribose) glycohydrolase (parg), the enzyme responsible for polymer turnover. parg was isolated from bovine thymus, yielding a protein of approximately 59 kda. based on the sequence of oligopeptides derived from the enzyme, polymerase chain reaction products and partial cdna clones were isolated and used to construct a ... | 1997 | 9115250 |
| nonaldehyde sterilization of biologic tissue for use in implantable medical devices. | biologic tissue stabilized by dye-mediated photooxidation has found application in implantable devices. the desire to avoid aldehydes in the processing of photooxidized tissues led to the development of a nonaldehyde, iodine based sterilant. the interaction of tissue with iodine was indicated by a change in tissue shrinkage temperature, dependent upon solution and incubation parameters. the amino acid tyrosine also was altered, presumably because of aromatic ring iodination. transmission electro ... | 1997 | 9116349 |
| preinfection in vitro chemotaxis, phagocytosis, oxidative burst, and expression of cd11/cd18 receptors and their predictive capacity on the outcome of mastitis induced in dairy cows with escherichia coli. | four to 6 wk after parturition, 12 cows in second, fourth, or fifth lactation were experimentally infected in one gland with escherichia coli. the capacity of chemotaxis, phagocytosis, oxidative burst, and expression of cd11/cd18 receptors to predict the severity of imi was measured. bacterial counts in the infected quarter, expressed as area under the curve, and residual milk production in the uninfected quarters were compared to determine severity of the infection. although these two outcome p ... | 1997 | 9120097 |
| evaluation of hematological, serum biochemical and cerebrospinal fluid parameters in experimental bacterial meningitis in the calf. | to evaluate the effects of bacterial meningitis on blood and csf parameters, an experiment was conducted with five iranian crossbred male calves. blood and csf samples were collected 3 times within a 5-day interval before the administration of bacteria for obtaining control values. following the injection of e. coli, k12 into the cerebrospinal fluid from the lumbosacral space, samples were collected and clinical signs of meningitis were observed. blood and csf samples were obtained from the meni ... | 1997 | 9123983 |
| influence of ozone on the susceptibility of escherichia coli k1 to the bactericidal action of serum. | the susceptibility to the bactericidal action of normal bovine serum of twenty two escherichia coli k1 strains, isolated from the urine of patients with urinary tract infections, was determined. only four strains were resistant. ozonization of bacterial suspensions enhanced the sensitivity of the strains to the action of both normal serum and a serum in which the alternative pathway of complement activation was thermally blocked. | 1996 | 9131796 |
| antibacterial peptides of bovine lactoferrin: purification and characterization. | three peptides with antibacterial activity toward enterotoxigenic escherichia coli have been purified from a pepsin digest of bovine lactoferrin. all peptides were cationic and originated from the n-terminus of the molecule in a region where a bactericidal peptide, lactoferricin b, had been previously identified. the most potent peptide, peptide i, was almost identical to lactoferricin b; the sequence corresponded to residues 17 to 42, and the molecular mass was 3195 as determined by mass spectr ... | 1997 | 9149961 |
| ard-1 cdna from human cells encodes a site-specific single-strand endoribonuclease that functionally resembles escherichia coli rnase e. | the human ard-1 (activator of rna decay) cdna sequence can rescue mutations in the escherichia coli rne gene, which specifies the essential endoribonuclease rnase e, resulting in rnase e-like cleavages in vivo in rne-defective bacteria and in vitro in extracts isolated from these cells (wang, m., and cohen, s. n. (1994) proc. natl. acad. sci. u. s. a. 91, 10591-10595). recent studies indicate that the 13.3-kda protein encoded by ard-1 cdna is almost identical to the carboxyl-terminal end of the ... | 1997 | 9153239 |
| "designing out" disulfide bonds: thermodynamic properties of 30-51 cystine substitution mutants of bovine pancreatic trypsin inhibitor. | we have used a combination of spectroscopic and calorimetric techniques to assess the thermodynamic and extrathermodynamic consequences of paired amino acid substitutions at positions 30 and 51 in bovine pancreatic trypsin inhibitor (bpti). correctly folded, wild type bpti contains a disulfide at the 30-51 positions, with the nonbackbone atoms of this cystine being relatively solvent inaccessible. mutants missing this buried 30-51 disulfide adopt a conformation very similar to that of the native ... | 1997 | 9154914 |
| monitoring the microbiology of high quality milk by monthly sampling over 2 years. | the concentrations of seven types of microorganism in the milk produced by farms using high quality milking procedures were monitored monthly. the most commonly encountered bacterium was pseudomonas, whose concentration varied greatly between samples, but lactococci, lactobacilli and yeasts were also present at more stable concentrations. staphylococcus aureus and beta-glucuronidase-positive escherichia coli were occasionally detected. listeria monocytogenes was found in the samples from only on ... | 1997 | 9161919 |
| structure of a truncated human surfactant protein d is less effective in agglutinating bacteria than the native structure and fails to inhibit haemagglutination by influenza a virus. | surfactant protein d (sp-d) is a lung-specific protein that is synthesized and secreted by lung epithelial cells and is believed to play an important role in lung host defence. this protein belongs to the c-type lectin family, which is characterized by an n-terminal cysteine-rich domain, a collagen-like domain, a neck domain and a carbohydrate recognition domain (crd). to elucidate the biological actions of this animal lectin against such pathogens as micro-organisms, the biological activities o ... | 1997 | 9163329 |
| membrane binding and enzymatic activation of a dbl homology domain require the neighboring pleckstrin homology domain. | dbl-homology (dh) domains are invariably located immediately n-terminal to a pleckstrin homology (ph) domain. to understand the functional relationship between these two domains we expressed the dh domain alone, the ph domain alone, and the dh-ph combination of the invasion inducing protein tiam-1 fused to glutathione-s-transferase (gst) or green fluorescent protein (gfp). we found that the gst-dh-ph and the gst-ph constructs bind to preparations of brain membranes and to the beta gamma subunits ... | 1997 | 9168986 |
| epidemiological relatedness and clonal types of natural populations of escherichia coli strains producing shiga toxins in separate populations of cattle and sheep. | two separate animal populations consisting of a herd of cattle (19 animals) and a flock of sheep (25 animals) were investigated for strains of escherichia coli producing shiga toxins (stec) over a time period of 6 months. thirty-three stec were isolated from 63.2% of cattle and grouped into 11 serotypes and eight electrophoretic types (ets) by multilocus enzyme analysis. in sheep, 88% of the animals excreted stec (n = 67 isolates) belonging to 17 different serotypes and 12 different ets. stec fr ... | 1997 | 9172336 |
| survival of escherichia coli o157:h7 in yoghurt during preparation and storage at 4 degrees c. | cow's milk was inoculated with ca 10(3) and 10(7) cfu ml-1 escherichia coli o157:h7. after fermentation at 42 degrees c for 0-5 h, the yoghurt was stored at 4 degrees c. two kinds of yoghurt were used: traditional yoghurt (ty), made with streptococcus thermophilus and lactobacillus bulgaricus starter cultures, and 'bifido' yoghurt (by), made with the two starter cultures plus bifidobacterium bifidum. after 7 d e. coli o157:h7 decreased from 3.52 to 2.72 log10 cfu ml-1 and from 7.08 to 5.32 log10 ... | 1997 | 9172440 |
| a 5-h screening and 24-h confirmation procedure for detecting escherichia coli o157:h7 in beef using direct epifluorescent microscopy and immunomagnetic separation. | an antibody-direct epifluorescent filter technique (ab-deft) detected 100% of the raw ground beef samples inoculated with escherichia coli o157:h7 cells (0.15 cells g-1) and incubated in a prewarmed, modified buffered peptone water (mbpw) non-selective enrichment broth for 5 h at 42 degrees c in an orbital shaking water bath (200 rev min-1). over 50% of the microscopic fields viewed were positive (1-10 fluorescent cells field-1) in the ab-deft. all positive screening results were confirmed withi ... | 1997 | 9172447 |
| cdna cloning, expression, and rapid purification of a kunitz-type winged bean chymotrypsin inhibitor. | a 183-residue kunitz-type winged bean chymotrypsin inhibitor (wbci), inhibits its cognate protease at a molar ratio of 1:2, instead of the usual ratio of 1:1 common to other members of the family. from the cdna pool obtained by reverse transcription of the poly(a)+ rna of the developing winged bean seeds, the structural gene of wbci has been amplified by pcr using primers designed to delete the 24-residue signal peptide and introduce ecori and sali sites at the ends of the amplified dna. the lat ... | 1997 | 9179296 |
| resazurin reduction as a function of respiratory burst in bovine neutrophils. | to determine whether the respiratory burst of neutrophils from bovine blood and milk can be analyzed by use of a fluorometric resazurin reduction assay. | 1997 | 9185965 |
| chaperone properties of the bacterial periplasmic substrate-binding proteins. | bacterial periplasmic substrate-binding proteins are initial receptors in the process of active transport across cell membranes and/or chemotaxis. each of them binds a specific substrate (e.g. sugar, amino acid, or ion) with high affinity. for transport, each binding protein interacts with a cognate membrane complex consisting of two hydrophobic proteins and two subunits of a hydrophilic atpase. for chemotaxis, binding proteins interact with specific membrane chemotaxis receptors. we report, her ... | 1997 | 9188448 |
| serine protease of pestiviruses: determination of cleavage sites. | the single-stranded genomic rna of pestiviruses is of positive polarity and encompasses one large open reading frame of about 4,000 codons. the resulting polyprotein is processed co- and posttranslationally by virus-encoded and host cell proteases to give rise to the mature viral proteins. a serine protease residing in the nonstructural (ns) protein ns3 (p80) has been shown to be essential for the release of the ns proteins located downstream of ns3. in this report the ns3 serine protease-depend ... | 1997 | 9188613 |
| variation in virulence in the gnotobiotic pig model of o157:h7 escherichia coli strains of bovine and human origin. | escherichia coli strains of serotype o157:h7 have been incriminated in outbreaks and sporadic cases of food-borne illness, including diarrhea, hemorrhagic colitis, hemolytic uremic syndrome and thrombotic thrombocytopenic purpura. food-producing animals, particularly cattle, are believed to be reservoirs of the organism. whether all strains of bovine origin pose human health risk is unknown and was the impetus for this investigation. we compared the virulence of ten slt-i, slt-ii, and eae dna pr ... | 1997 | 9191990 |
| verotoxigenic escherichia coli in slaughter cattle and ground beef in south dakota. | 1997 | 9191996 | |
| hemolysin phenotypes and genotypes of eaea-positive and eaea-negative bovine verotoxigenic escherichia coli. | intimin or eaea protein has been implicated in the attaching/effacing lesion caused by entero-hemorrhagic escherichia coli (ehec) in the intestine but it is not produced by all ehec and is therefore not adequate as a marker for ehec. hemolysins are produced by a high percentage of verotoxigenic e. coli (vtec) and could be a marker for ehec, but their distribution and relation to virulence are not known. we used pcr amplification to determine the presence or absence of eaea sequences in 281 vtec ... | 1997 | 9192033 |
| a novel developmental process of intestinal epithelial lesions in a calf infected with attaching and effacing escherichia coli. | a comparative study on the adhesion of attaching and effacing escherichia coli (aeec) to the enterocytes between the colon of a calf and the jejunum of a piglet showed differences in the developmental process of attaching and effacing (ae) lesions. in the calf, pedestals consisted of fused microvilli, while in the piglet they developed from the apical epithelial cell membranes after effacing microvilli. microvilli adjacent to the aeec attachment site were atrophic in the calf, whereas they were ... | 1997 | 9192365 |
| characterization of a specific mycobacterium paratuberculosis recombinant clone expressing 35,000-molecular-weight antigen and reactivity with sera from animals with clinical and subclinical johne's disease. | johne's disease is a chronic enteritis of ruminants associated with enormous worldwide economic losses for the dairy cow- and goat-rearing industries. management limitations and eradication programs for this disease have been hampered by the lack of a simple and specific diagnostic test for the detection of subclinical cases. we used a recombinant clone expressing a 35,000-molecular-weight mycobacterium paratuberculosis antigen (p35 antigen) from a previously constructed expression library of m. ... | 1997 | 9196196 |
| [federal investigations on the distribution and in vitro resistance of udder pathogenic bacteria in the milk of cows with subclinical mastitis]. | 1644 quarter milk samples of 948 dairy cows with subclinical mastitis, collected from 63 veterinary practices all over germany origined by 262 livestocks with problems in udder health were examined semiquantitatively by "aulendorfer mastitistest" for cell count and additionally bacteriologically. potentially udder pathogenic bacteria were tested for in vitro-sensitivity to penicillin g, ampicillin, oxacillin, cefacetril, tylosin, neomycin, gentamicin, polymyxin b and enrofloxacin. 24.5% of all t ... | 1997 | 9198960 |
| global aspects of emerging and potential zoonoses: a who perspective. | many new human pathogens that have emerged or reemerged worldwide originated from animals or from products of animal origin. many animal species as well as categories of agents have been involved in the emergence of diseases. wild (e.g., bats, rodents) as well as draught animals (e.g., horses) and food animals (e.g., poultry, cattle) were implicated in the epidemiologic cycles of these diseases. many of the agents responsible for new infections and diseases in humans were viruses (e.g., hantavir ... | 1997 | 9204308 |
| sensitization of the bovine mammary gland to escherichia coli endotoxin. | the effect of repeated infusions of escherichia coli endotoxin on the acute phase response in the bovine mammary gland was assessed through the concentrations of tumor necrosis factor alpha (tnf-alpha) in milk. four clinically normal lactating cows received two intramammary infusions of e coli endotoxin (33 micrograms) 24 h apart in the same mammary quarter. along with the second infusion, the cows received one dose of endotoxin in the contralateral quarter. milk was collected at varying interva ... | 1997 | 9208443 |
| selective modification at the n-terminal region of human growth hormone that shows antagonistic activity. | a new analogue of recombinant human growth hormone (hgh), hgh des(1-6,14) was expressed in escherichia coli, refolded and purified to homogeneity. the mutation decreased the hormone's ability to bind lactogenic and somatogenic receptors through its site 1, and almost completely abolished its ability to bind these receptors through site 2, as evidenced by both binding and gel-filtration experiments. more specifically, the binding to prolactin receptors (prlrs) from various species or their solubl ... | 1997 | 9220030 |
| expression of ovine interleukin-2 cdna in escherichia coli. | the expression plasmids pgex-2t and pt7-7 were used to express ovine (ov) il-2 cdna in escherichia coli. the pgex-2t vector contained glutathione-s-transferase (gst) as the affinity handle and resulted in high level expression of the gst-il-2 fusion protein. however, only a small proportion of this fusion protein was present in the soluble fraction. the insoluble fraction was extracted with a detergent, sarkosyl, and even though a large amount of fusion product was obtained, it would not bind to ... | 1997 | 9220585 |
| thermal activation of the bovine hsc70 molecular chaperone at physiological temperatures: physical evidence of a molecular thermometer. | differential scanning calorimetry was used to monitor the thermal transitions of the 70 kda heat shock cognate protein (hsc70). hsc70 had endothermic transitions with midpoints (tm) at 59 degrees c and 63 degrees c in the absence and presence of atp, respectively, and a similar increase in tm was observed using intrinsic fluorescence of tryptophan. combined with increased exposure at 60 degrees c of non-polar residues of hsc70 to which the hydrophobic, fluorescent probe ans bound, these data ind ... | 1996 | 9222592 |
| the effect of discontinuation of postmilking teat disinfection in low somatic cell count herds. ii. dynamics of intramammary infections. | results of a 20 month split-udder trial on the effect of discontinuation of postmilking teat disinfection on intramammary infections (imi) with major and minor pathogens in seven dairy herds with a low somatic cell count are described. the incidence of escherichia coli imi was found to be significantly lower, whereas the incidence of imi with staphylococcus aureus and minor pathogens was significantly higher in quarters for which postmilking teat disinfection was discontinued than in disinfected ... | 1997 | 9225431 |
| expression of p, s, and f1c adhesins by cytotoxic necrotizing factor 1-producing escherichia coli from septicemic and diarrheic pigs. | nineteen papc-positive cytotoxic necrotizing factor 1 (cnf1)-producing escherichia coli isolates from pigs with septicemia or diarrhea were tested for the presence of pap-, sfa-, and afa-related sequences encoding p/prs, s/f1c, and dr/afa adhesins respectively. production of adhesins by isolates was tested by mannose-resistant hemagglutination (mrha), sialidase treatment of erythrocytes and particle agglutination tests. production of p, s, and f1c fimbriae by isolates was also examined by immuno ... | 1997 | 9231424 |
| endotoxaemia in dairy cattle: mechanism of reticulorumen stasis. | the objective of this study was to determine whether blockade of alpha(-2) adrenergic receptors would restore reticulorumen motility during toxaemia in cows. reticulorumen contractions were measured via a water-filled balloon connected to a pressure transducer. intravenous infusion of endotoxin (100 ng kg-1 over 30 min) significantly decreased the number of reticulorumen contractions. intravenous infusion of yohimbine (125 micrograms kg-1 over 30 min) alone did not affect reticulorumen contracti ... | 1997 | 9232121 |
| evaluation of blood acid-base balance after experimental administration of endotoxin in adult cow. | esherichia coli endotoxin was administered intravenously to 7 holstein adult cows, to evaluate the effect of endotoxin on acid-base balance. endotoxin shock was observed immediately after the administration of endotoxin. a loss of appetite and depression of digestive tract motility continued for about 120 hr after the challenge. metabolic alkalosis following hypochloremia and hypokalemia were particularly pronounced at 12 to 72 hr after the administration of endotoxin. | 1997 | 9234228 |
| complement fragment c5a and inflammatory cytokines in neutrophil recruitment during intramammary infection with escherichia coli. | generation of inflammatory mediators and leukocyte recruitment to infection at an epithelial surface were studied during escherichia coli-induced mastitis. one uninfected gland of each of eight midlactation cows was challenged with only 30 cfu of e. coli mcdonald strain 487, a serum-resistant isolate from a cow with mastitis. bacteria grew logarithmically during the first 10 to 12 h after challenge, reaching concentrations of more than 10(5) cfu/ml with no detectable host response during this ti ... | 1997 | 9234788 |
| synthesis and characterization of selenolipoylated h-protein of the glycine cleavage system. | h-protein of the glycine cleavage system has a lipoic acid prosthetic group. selenolipoic acid is a lipoic acid analog in which both sulfur atoms are replaced by selenium atoms. two isoforms of bovine lipoyltransferase that are responsible for the attachment of lipoic acid to h-protein had an affinity for selenolipoyl-amp and transferred the selenolipoyl moiety to bovine apoh-protein comparable to lipoyl-amp. selenolipoylated h-protein was overexpressed in escherichia coli and purified. selenoli ... | 1997 | 9242652 |
| microbiological composition of raw milk from selected farms in the camembert region of normandy. | raw milk from 27 farms was sampled over 6 months for listerias, salmonellas, yersinia enterocolitica and campylobacters. total bacterial counts and somatic cell counts were measured. lactococci, lactobacilli, dextran-producing leuconostocs, brevibacterium linens, yeasts and moulds, staphylococcus aureus and other micrococcaceae, pseudomonas, coliforms, escherichia coli, enterococci, clostridium perfringens and spores of anaerobic lactate-fermenting bacteria were also counted. pseudomonas (2000 c ... | 1997 | 9246770 |
| endotoxin induces endothelial barrier dysfunction through protein tyrosine phosphorylation. | bacterial lipopolysaccharide (lps) induces actin reorganization, intercellular gap formation, and endothelial barrier dysfunction in vitro. we studied whether lps-induced increments in 14c-labeled bovine serum albumin (bsa) flux across bovine pulmonary artery endothelial cell (ec) monolayers and actin depolymerization are mediated through protein tyrosine phosphorylation. lysates from ec exposed to lps derived from escherichia coli 0111:b4 (100 ng/ml, 1 h) demonstrated increased tyrosine phospho ... | 1997 | 9252559 |
| outbreak of clinical mastitis in dairy cows following 'blitz' therapy. | 1997 | 9253837 | |
| immunolocalization of the pseudorabies virus immediate-early protein ie180 by immunoperoxidase staining. | the immediate-early (1e) gene of pseudorabies virus (prv) expresses immediately upon infection, a phosphorylated protein (immediate-early protein, ie180) that can transactivate viral other genes and plays an essential role in regulating viral gene expression. in order to detect and localize ie180 in infected cells early on, this gene was cloned for overexpression, and the expressed products were applied to generate specific antibodies against ie180 protein. two recombinant expression plasmids pn ... | 1997 | 9255733 |
| the crystal structure of the nucleotide-free alpha 3 beta 3 subcomplex of f1-atpase from the thermophilic bacillus ps3 is a symmetric trimer. | f1-atpase, an oligomeric assembly with subunit stoichiometry alpha 3 beta 3 gamma delta epsilon, is the catalytic component of the atp synthase complex, which plays a central role in energy transduction in bacteria, chloroplasts and mitochondria. the crystal structure of bovine mitochondrial f1-atpase displays a marked asymmetry in the conformation and nucleotide content of the catalytic beta subunits. the alpha 3 beta 3 subcomplex of f1-atpase has been assembled from subunits of the moderately ... | 1997 | 9261073 |
| role of domains in escherichia coli and mammalian mitochondrial elongation factor ts in the interaction with elongation factor tu. | bovine mitochondrial elongation factor ts (ef-tsmt) stimulates the activity of escherichia coli elongation factor tu (ef-tu). in contrast, e. coli ef-ts is unable to stimulate mitochondrial ef-tu. ef-tsmt forms a tight complex with e. coli ef-tu governed by an association constant of 8.6 x 10(10). this value is 100-fold stronger than the binding constant for the formation of the e. coli ef-tu.ts complex. to test which domain of ef-tsmt is important for its strong binding with ef-tu, chimeras wer ... | 1997 | 9268331 |
| recombinant uracil phosphoribosyltransferase from the thermophile bacillus caldolyticus: expression, purification, and partial characterization. | the upp gene encoding the major uracil phosphoribosyltransferase (uprt) of the thermophile bacillus caldolyticus was cloned by complementation of an escherichia coli upp mutation. the nucleotide sequence of the cloned dna revealed an open reading frame of 630 bp encoding a polypeptide of 209 amino acids (m(r) 22,817) with 84% amino acid sequence identity to the deduced upp gene product of bacillus subtilis. primer extension analysis indicated that the transcriptional start site of the cloned gen ... | 1997 | 9268683 |
| detection and characterization of enterohaemorrhagic escherichia coli in slaughtered cattle. | fecal samples from slaughtered cattle were studied for enterohaemorrhagic escherichia coli (ehec) by dna hybridization with biotin-labelled dna probes specific for the ehec virulence plasmid, shiga-like toxin i (slt i), shiga-like toxin ii (slt ii) and eae gene. among 136 animals analysed, 47 (34.5%) were found to carry ehec. the cytotoxic genotypes observed for ehec strains were: 60.4% slt i, 12.5% slt ii and 10.4% slt i + slt ii; 16.7% resulted slt i and slt ii negative. a total of 14 out of 4 ... | 1997 | 9270349 |
| molecular cloning of the complementary dna for an additional member of the family of aortic aneurysm antigenic proteins. | we have purified and partially sequenced a protein from the adventitia of the human aorta (aortic aneurysm antigenic protein 40 kda; aaap-40) that has homologies to bovine aortic microfibril-associated glycoprotein (magp-36). it is immunoreactive with immunoglobulin g (iggs) purified from the serum and aortic wall of patients with abdominal aortic aneurysms. aaap-40 and magp-36 have fibrinogen-like and vitronectin-like motifs. screening an expression library constructed from human aortic adventi ... | 1997 | 9279320 |
| activation of endothelial cell phospholipase d by migrating neutrophils. | vascular endothelium plays a critical role in regulating the integrity of intercellular adhesive and junctional contacts in response to migrating neutrophils during the inflammatory process. biochemical responses induced in endothelial cells by adherent, migrating neutrophils are poorly understood. this study was undertaken to explore the possibility that endothelial cell phospholipase d (pld) is activated when neutrophils migrate through endothelial cell monolayers in response to chemotactic st ... | 1997 | 9291695 |
| purification and characterization of the protein kinase encoded by the ul13 gene of herpes simplex virus type 2. | the proteins encoded by the ul13 genes of herpes simplex virus types 1 (hsv-1) and 2 (hsv-2) have been predicted to be protein kinases. to identify the ul13 gene product, we have raised a rabbit polyclonal antiserum against a his.tag-hsv-1 ul13 fusion protein. the antibody specifically reacted with the 60-kda ul13 fusion protein expressed in escherichia coli and also recognized 56- to 57-kda late proteins in nuclear fractions of hsv-1- and hsv-2-infected cells. on the other hand, novel casein ki ... | 1997 | 9300039 |
| chinese hamster protein homologous to human putative protein kinase kiaa0204 is associated with nuclei, microtubules and centrosomes in cho-k1 cells. | monoclonal antibody raised against a preparation of loach fish sperm centrosomes was used for screening of cdna expressing library of chinese hamster cho-k1 cells. two positive clones appeared to encode 628 amino acid protein fragment that was 72% identical to human kiaa0204 protein, i.e. putative protein kinase. polyclonal antibodies raised against products of cdna expression in e. coli recognized 210-kda polypeptide in cho-k1 cells and immunostained nuclear speckles, centrosomes and microtubul ... | 1997 | 9305747 |
| biochemical evidence that saccharomyces cerevisiae ygr262c gene, required for normal growth, encodes a novel ser/thr-specific protein kinase. | saccharomyces cerevisiae ygr262c gene, whose disruption causes severely defective growth, encodes a putative protein kinase shorter than any other protein kinase biochemically characterized to date and lacking some of the conserved features of these enzymes. here we show that the product of the ygr262c gene, pid261, expressed in e. coli with a c-terminal (his)6 tag, is a bona fide ser/thr protein kinase as judged from its capability to autophosphorylate and to phosphorylate casein and osteoponti ... | 1997 | 9305753 |
| mammalian protein rap46: an interaction partner and modulator of 70 kda heat shock proteins. | a ubiquitously expressed nuclear receptor-associating protein of approximately 46 kda (rap46) was identified recently. interaction experiments with in vitro-translated proteins and proteins contained in cell extracts revealed that a great variety of cellular regulators associate with rap46. however, in direct interaction tests by the far-western technique, only 70 kda proteins showed up and were identified as members of the 70 kda heat shock protein (hsp70) family. interaction is specific since ... | 1997 | 9312007 |
| characterization of a gdp dissociation inhibitory region of adp-ribosylation factor domain protein ard1. | adp-ribosylation factors (arfs) are approximately 20-kda guanine nucleotide-binding proteins initially identified by their ability to stimulate cholera toxin adp-ribosyltransferase activity and later recognized as critical components in intracellular vesicular transport and phospholipase d activation. arf domain protein 1 (ard1) is a member of the arf family that differs from other arfs by the presence of a 46-kda amino-terminal extension. we previously reported that this extension acts as a gtp ... | 1997 | 9312116 |
| a simple filtration technique to detect enterohemorrhagic escherichia coli o157:h7 and its toxins in beef by multiplex pcr. | primers, specific for a unique base substitution in uida of escherichia coli o157:h7, were coupled with oligonucleotides for the shiga-like toxin i (slt-i) and slt-ii genes in a multiplex pcr assay. a minimum of 10(2) cfu per pcr (10 microliters) was necessary to amplify e. coli o157:h7-specific bands by multiplex pcr. food particles as well as various unknown metabolic by-products of bacteria inhibited the pcr, but a simple two-step filtration procedure eliminated this inhibition. to reliably g ... | 1997 | 9327582 |
| cholelithiasis and cholecystitis in a dairy cow. | a 9-year-old holstein cow was evaluated for colic and decreased milk production of 2 days' duration. preoperative serum biochemical results suggested hepatic damage and cholestasis. on the basis of persistent signs of abdominal pain that were nonresponsive to analgesics, exploratory laparotomy was performed. the cow was found to have choleliths. cholecystocentesis was performed, and samples were submitted for cytologic examination and bacterial culture. bacterial culture yielded escherichia coli ... | 1997 | 9333096 |
| effects of 4-ipomeanol on bovine alveolar macrophage function. | the objective of this study was to determine whether 4-ipomeanol toxicosis in calves impairs alveolar macrophage functions important in pulmonary defense against infectious agents. male holstein calves were given either 4-ipomeanol (3 mg kg-1, i.v.) or vehicle (polyethylene glycol 400). alveolar macrophages were recovered by pulmonary lavage 3 days later, and their capacities to phagocytose and kill e. coli, migrate toward zymosan-activated immune bovine serum, and produce interferon and interle ... | 1997 | 9336881 |
| interaction of the dna topoisomerase ii catalytic inhibitor meso-2,3-bis(3,5-dioxopiperazine-1-yl)butane (icrf-193), a bisdioxopiperazine derivative, with the conserved region(s) of eukaryotic but not prokaryotic enzyme. | icrf-193 [meso-2,3-bis(3,5-dioxopiperazine-1-yl)butane], a bisdioxopiperazine compound, has been shown to be a catalytic inhibitor of dna topoisomerase ii by stabilizing the enzyme in the form of a closed "protein clamp," an intermediate form in the catalytic cycle (roca et al., proc natl acad sci usa 91: 1781-1785, 1994). in view of its usefulness as a probe in the functional analysis of the enzyme, we tried further to define the domain(s) of the enzyme interacting with the drug by examining it ... | 1997 | 9337070 |
| n-terminal truncation mutagenesis of equinatoxin ii, a pore-forming protein from the sea anemone actinia equina. | the role of the n-terminal segment 1-33 of equinatoxin ii, a 20 kda pore-forming protein from the sea anemone actinia equina, was studied by n-truncation mutagenesis. a part of this segment was classified as being amphiphilic and membrane seeking. wild-type equinatoxin ii and its mutants lacking 5, 10 and 33 amino acid residues, respectively, were produced in escherichia coli using t7 rna polymerase-based expression vector. soluble recombinant proteins were isolated from bacterial lysates and as ... | 1997 | 9342140 |
| detection of stec and epidemiological investigations in surrounding of a hus patient. | after occurrence of a case of hus infection in a 2-year-old infant from a dairy farmer's family living near oldenburg, investigations were performed in the infant's surrounding in order to elucidate the route of infection. since hospitalization took place at a late stage, it was not possible to isolate ehec from the patient's stool samples. however, e. coli o157 antibody determinations in serum were positive. since stec of serogroup o157 were found in faeces from the 34 dairy cows of the farm, s ... | 1997 | 9342886 |
| a structural requirement of zinc for the folding of recombinant link protein. | we have cloned and ligated a full-length bovine link protein (lp) in the pmal-c2 vector and overexpressed it in fusion with maltose-binding protein (mbp) in escherichia coli. we have demonstrated dose-dependent binding of mbp/lp to biotinylated hyaluronan in a dot blot assay. a greater percentage of the expressed fusion protein was soluble, monomeric, and undegraded when the growth temperature was lowered, the growth medium was supplemented with zinc, and metal chelators were omitted from the ly ... | 1997 | 9344458 |
| a stable alpha-helical domain at the n terminus of the rialpha subunits of camp-dependent protein kinase is a novel dimerization/docking motif. | the rialpha subunit of camp-dependent protein kinase is maintained as an asymmetric dimer by a dimerization motif at the n terminus. based on resistance to proteolysis and expression as a discrete domain in escherichia coli, this motif is defined as residues 12-61. this motif is chemically, kinetically, and thermally stable. the two endogenous interchain disulfide bonds between cys16 and cys37 in rialpha are extremely resistant to reduction even in 8 m urea, indicating that they are well shielde ... | 1997 | 9353302 |
| application of recombinant bovine viral diarrhea virus proteins in the diagnosis of bovine viral diarrhea infection in cattle. | the national animal disease laboratory (nadl) vaccine strain of bovine viral diarrhea virus (bvdv) genes for gp48 and p80 were expressed in escherichia coli. the bvdv-nadl gene for gp62 was integrated into a baculovirus genome for expression in spodoptera frugiperda (sf-9) insect ovarian cells. the antigenicity of baculovirus expressed bvdv protein was detected by anti-bvdv specific antibodies in an enzyme-linked immunosorbent assay (elisa), indirect immunofluorescent assay (ifa) and radio-immun ... | 1997 | 9355247 |
| responses of antibody titers to intramammary immunization with escherichia coli j5 bacterin. | the effect of an immunization schedule on responses of antibody titers was tested following vaccination with an escherichia coli j5 bacterin. eighteen cows were equally distributed among three immunization schedules: 1) subcutaneous injection at 14 d prior to the end of lactation, intramammary immunization at 7 d after drying off, and subcutaneous injection at 30 d into the dry period; 2) subcutaneous injections at drying off, at 30 d into the dry period, and within 12 h after calving; and 3) un ... | 1997 | 9361212 |
| virulence factors of verocytotoxin-producing escherichia coli isolated from raw meats. | pcr for verocytotoxin-producing escherichia coli (vtec) was positive in 4.6% of 2,440 raw meat samples; only beef, sheep, and venison samples were positive. none of the isolated vtec strains belonged to serogroup o157. additional virulence factors were detected in only a minority of strains, suggesting that most of these meat vtec isolates are not pathogenic. | 1997 | 9361444 |
| a 1-year study of escherichia coli o157 in cattle, sheep, pigs and poultry. | samples of rectal faeces were collected immediately after slaughter from 400 cattle each month for a 1-year period and from 1000 each of sheep, pigs and poultry over the same period. samples were examined for escherichia coli o157 by enrichment culture in buffered peptone water with vancomycin, cefixime and cefsulodin followed by immunomagnetic separation and culture of magnetic particles onto cefixime tellurite sorbitol macconkey agar. e. coli o157 was isolated from 752 (15.7%) of 4800 cattle, ... | 1997 | 9363024 |
| persistence of escherichia coli o157:h7 in dairy cattle and the dairy farm environment. | the persistence of escherichia coli o157:h7 in cattle and the farm environment was investigated on eight ontario dairy farms positive for e. coli o157:h7 in a longitudinal study commenced one year previously. faecal samples from cows, calves, humans, cats, rodents, wild birds, a composite fly sample and numerous composite and individual environmental samples were cultured and tested for verotoxin-producing e. coli (vtec). vtec isolates were serotyped and e. coli o157:h7 isolates were phage typed ... | 1997 | 9363025 |
| bovine spongiform encephalopathy: is it an autoimmune disease due to bacteria showing molecular mimicry with brain antigens? | bovine spongiform encephalopathy (bse) could be an autoimmune disease produced following exposure of cattle to feedstuffs containing bacteria showing molecular mimicry between bacterial components and bovine tissue. analysis of molecular sequence databases (genbank and swissprot) shows that three bacteria (acinetobacter calcoaceticus,ruminococcus albus, and agrobacter tumefaciens) share sequences with the encephalitogenic peptide of bovine myelin, while three molecules in escherichia coli show m ... | 1997 | 9370514 |
| a genomic polymorphism located downstream of the gcvp gene of escherichia coli that correlates with ecological niche. | current evolutionary theory proposes that niche-adapted microbial populations might evolve through selection for favoured genotypes followed by clonal expansion (maynard-smith, 1991). possible correlations between genomic variation and ecological niche in escherichia coli isolates derived from human and animal sources were investigated by randomly amplified polymorphic dna (rapd) analysis. a 1.6-kb polymorphic marker was identified which was present in 60% of isolates from human clinical specime ... | 1997 | 9394461 |
| localization of the heme binding region in soluble guanylate cyclase. | soluble guanylate cyclase (sgc) is a heterodimeric hemoprotein composed of alpha1 and beta1 subunits. sgc is activated by nitric oxide (no) and therefore plays a central role in no signal transduction. activation of sgc by no is believed to be mediated by the interaction between no and the heme of sgc. spectroscopic and kinetic studies have shown that the heme of sgc is in a unique environment. characterization of the heme environment is critical to the understanding of the mechanism of no activ ... | 1997 | 9398330 |
| characterization of the pasteurella haemolytica transferrin receptor genes and the recombinant receptor proteins. | the tbpa and tbpb genes encoding the transferrin receptor proteins, tbpa and tbpb, from pasteurella haemolytica a1 were cloned, sequenced and expressed in escherichia coli. the genes were organized in a putative operon arrangement of tbpb- tbpa. the tbpb gene was preceded by putative promoter and regulatory sequences, and followed by a 96 base pair intergenic sequence in which no promoter regions were found, suggesting that the two genes are coordinately transcribed. the deduced amino acid seque ... | 1997 | 9405205 |
| 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 |
| inhibitory effect on lps-induced tumor necrosis factor in calves treated with chlorpromazine or pentoxifylline. | the inhibitory effect of chlorpromazine (cpz), pentoxifylline (ptx) and dexamethasone (dex) was investigated in a model of endotoxin shock in holstein calves following an intravenous administration of esherichia coli endotoxin (lps). initial correlations with its effects on the levels of tumor necrosis factor (tnf), a pivotal mediator of endotoxin shock, and clinical signs were obtained. the pretreatment of cpz or dex significantly decreased the serum levels of tnf, and reduced endotoxic shock. ... | 1997 | 9409530 |
| [detection and occurrence of verotoxin-forming and/or shigatoxin producing escherichia coli (vtec and/or stec) in milk]. | raw milk contaminated with vtec was described as a source of human ehec infection. diagnosis of vtec from milk is complicated by the low number of vt-positive cells in the total bacterial count, the great variety of serovars with different combinations of virulence markers and the lack of characteristic biochemical properties for the cultural detection of all vtec. the graduated procedure presented and used for the examination of milk samples is based on vt detection in suitable enrichment cultu ... | 1997 | 9412452 |
| the 'assembly-promoting sequence region' of microtubule-associated protein 4 failed to promote microtubule assembly. | in order to study the function of the bovine map4 microtubule-binding domain (the assembly-promoting (ap) sequence region), a fragment corresponding to the ap sequence region was prepared using an escherichia coli expression system. when the fragment was mixed with purified tubulin at 37 degrees c, the fragment caused a time- and dose-dependent turbidity increase, and the fragment bound to tubulin. however, the products were cold-stable, and amorphous aggregates were observed by electron microsc ... | 1997 | 9414090 |
| cloning and expression of bovine corneal antigen cdna. | a cornea-associated antigen (co-ag) has been found to be the target for autoantibodies in patients with mooren's ulcer. the study goals were to isolate a full-length clone encoding co-ag from a bovine corneal cdna library and to express this clone in escherichia coli (e. coli). | 1997 | 9426958 |
| 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 |
| [optimization of the polymerase chain reaction (pcr) for detection and characterization of shigatoxin producing escherichia coli (stec) in food]. | the polymerase chain reaction (pcr) was improved to detect shigatoxin producing escherichia coli (stec) in milk. numbers of colony forming units (cfu) in test samples, concentrations and types of primers, amount of mgcl2, types of thermostable dna-polymerase, and cycling programs were modified up to obtain the cleanest electrophoretic pattern and the highest sensitivity. experimental conditions for further characterization of stec-isolates by means of pcr are given by summarizing data from liter ... | 1997 | 9451840 |
| giving selenium supplements to dairy cows strengthens the inflammatory response to intramammary infection and induces a growth-suppressing effect on mastitis pathogens in whey. | supplementing the feed of selenium-deficient diary cows with selenium (se)-yeast or selenite at a level of 0.2 p.p.m. induced self-cure of subclinical mastitis; the prevalence of quarters harbouring subclinical mastitis (bacteriological criteria) decreased to about one half during the 8 week supplementation period. three phenomena became apparent to explain the beneficial effect of selenium on mastitis: 1. the recruitment of phagocytes to the infected milk compartment of the udder was improved d ... | 1997 | 9465776 |
| detection of vtec using specific dna probes and complex typing of escherichia coli o157. | the incidence of e. coli causing hemorrhagic colitis (hc) or non-bloody enteritis in hungary was studied using slt-i and slt-ii gene-probes as well as vero-cell toxicity and verotox-f tests. out of 41 e. coli o157 strains isolated in hungary between 1987 and 1996 15 strains (o157:hnm 4, o157:h77 8, o157:hnt 3) derived from hemorrhagic colitis (hc). hybridization was observed with slt-i and/or slt-ii in 19 strains. verocytotoxin production of e. coli of 23 other serotypes was proven by hybridizat ... | 1997 | 9468730 |
| 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 |
| efficacy of parenteral administration of three antimicrobial agents in treatment of clinical mastitis in lactating cows: 487 cases (1989-1995). | to evaluate the efficacy of parenteral administration of procaine penicillin g, spiramycin, or enrofloxacin in the treatment of clinical mastitis in lactating cows. | 1998 | 9470054 |
| [current resistance status of escherichia coli strains from bovine mastitis milk samples]. | between december 1996 and march 1997, 95 e.coli strains were isolated from mastitis milk samples from 95 different animals. in 29.5% resistance could be observed against one or several of the examined antibiotics. however, cefoperazone, polymyxin b, colistin and gentamycin proved effective against the majority of these strains. between 0 and 23% of e.coli were resistant against the single tested antibiotics. as opposed to earlier investigations a smaller number of chloramphenicol-resistant strai ... | 1997 | 9480542 |
| intergenic suppression of the gammam23k uncoupling mutation in f0f1 atp synthase by betaglu-381 substitutions: the role of the beta380delseed386 segment in energy coupling. | we previously demonstrated that the escherichia coli f0f1-atp synthase mutation, gammam23k, caused increased energy of interaction between gamma- and beta-subunits which was correlated to inefficient coupling between catalysis and transport [al-shawi, ketchum and nakamoto (1997) j. biol. chem. 272, 2300-2306]. based on these results and the x-ray crystallographic structure of bovine f1-atpase [abrahams, leslie, lutter and walker (1994) nature (london) 370, 621-628] gammam23k is believed to form ... | 1998 | 9480879 |
| 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 |
| purification and characterization of the hnda subunit of nadp-reducing hydrogenase from desulfovibrio fructosovorans overproduced in escherichia coli. | based on the dna sequence of its structural genes, clustered in the hnd operon, the nadp-reducing hydrogenase of desulfovibrio fructosovorans is thought to be a heterotetrameric complex in which hnda and hndc constitute the nadp-reducing unit and hndd constitutes the hydrogenase unit, respectively. the weak representativity of the enzyme among cell proteins has prevented its purification. this paper discusses the purification and characterization of the hnda subunit of this unique tetrameric iro ... | 1998 | 9485416 |
| isolation from an ant myrmecia gulosa of two inducible o-glycosylated proline-rich antibacterial peptides. | reported here is the isolation and characterization of two antibacterial peptides synthesized in an ant myrmecia gulosa in response to bacterial challenge. the peptides were purified by reversed-phase high performance liquid chromatography and characterized by peptide sequencing and mass spectrometry. both peptides were formed from 16 amino acids, were rich in proline ( approximately 30%), and had n-acetylgalactosamine o-linked to a conserved threonine. the activity of a synthetic non-glycosylat ... | 1998 | 9497332 |
| infectious agents associated with diarrhoea of calves in the canton of tilarán, costa rica. | a case-control study of calves under 3 months of age was carried out by weekly visits to 15 farms in the canton of tilarán, costa rica. most farms were dedicated to beef or dual-purpose (dp) production. faecal samples were collected over a 6-month period from a total of 194 calves with clinical signs and from 186 animals without clinical signs of diarrhoea as assessed by a scoring system. the samples were investigated for the presence of viruses, bacteria and parasites. torovirus was detected fo ... | 1998 | 9500174 |