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[blood bactericidal activity in calves].methodical aspects relating to determination of serum-bactericidal capacities were studied, with the view to using them to test the bearing of abiotic environmental factors on defence mechanisms against infections. communicated are methodical experience by which to enhance the methods used to higher accuracy as well as experience regarding biological variance in calf and results obtained from follow-up checks in which antigens were systematically used. reference is made also to other methodical ...19807006553
variation in the susceptibility of bovine mycoplasmas to killing by the alternative complement pathway in bovine serum.all but one of nine acholeplasma strains were susceptible to killing by gnotobiotic-calf serum while all but one of fifteen mycoplasma strains were resistant. the mechanism of killing was examined using inhibitors of complement, viz. edta. mgegta. epsilon-amino caproic acid, and also by desalting serum and adding mgcl2 and cacl2. the results indicated that, when strains were killed by serum from gnotobiotic calves it was by the alternative complement pathway. however, experiments with mycoplasma ...19807007210
differences in inhibition of the growth of commensal and enteropathogenic strains of escherichia coli by lactotransferrin and secretory immunoglobulin a isolated from human milk.immunoglobulins from bovine and human colostrum and milk and lactotransferrin (ltf) from human milk were investigated for bacteriostatic activity against escherichia coli growing in a tissue culture medium. when tested separately, ltf or secretory immunoglobulin a (siga) from pooled human milk showed only slight bacteriostatic activity against human commensal or enteropathogenic strains of e. coli. together, they had a considerable bacteriostatic effect, but only against strains of enteropathoge ...19807007213
comparison between milk deprivation and oral rehydration with a glucose-glycine-electrolyte formulation in diarrhoeic and transported calves.treatment of diarrhoeic calves by oral administration of a glucose-glycine-electrolyte solution (gges) was compared with milk deprivation (water given instead) and with no treatment (milk-fed controls). the diarrhoea followed challenge with enteropathogenic escherichia coli. the gges group showed a significantly lower mortality (5 per cent) in comparison with the controls (37 per cent). the milk-deprived group had a slightly lower mortality (30 per cent) in comparison with the controls. the milk ...19807008333
[infant mouse model of "escherichia coli" infectious diarrhoea (author's transl)].three enteropathogenic bovine strains of escherichia coli (b41, b44 and 17c), carrying k99 antigen (k99+) and producing heat-stable enterotoxin (ent+), caused infectious diarrhoea when administered orally to swiss of1 and cd-1 infant mice. a mortality rate of 40 t0 60% was obtained after administration of 10 e. coli b41 to mice which were less than 48 h old. a mortality rate of 80 to 100% was obtained with 10(3) e. coli b41, selected as reference inoculum. inoculation of mice older than 48 h wit ...19807008674
identification of a class of lysines within the non-specific dna-binding site of rna polymerase core enzyme from escherichia coli.the imido ester, methyl acetimidate, which specifically amidinates lysine residues, modifies rna polymerase core enzyme, leading to rapid loss of activity. calf thymus dna partially protects the enzyme against this inactivation, an effect which disappears at high salt concentration. dna protects 17 +/- 6 lysines from amidination at low salt concentration. the dependence of amidination on methyl acetimidate concentration is examined in the presence of dna at high and low salt concentration. analy ...19806804229
spontaneous emergence of an hfr strain with a cit plasmid from natural isolates of citrate-positive escherichia coli bovine origin.from citrate-utilizing (cit+) escherichia coli strain c53 of bovine origin, strains c53a and c53b were obtained. upon mating with reca+ but not with reca mutant recipients of k-12, c53a produced chromosomal recombinants at quite high frequencies, leading to the following conclusions: (i) c53a is an hfr strain; (ii) the site of integration of the cit plasmid (inch1) is between meta (89 min) and ara (1 min); (iii) the direction of chromosome transfer is clockwise; and (iv) the plasmid-associated d ...19807009550
[demonstration of enteropathogenic e. coli by the ligated intestinal segment technic].through the implementation of the technique of ligated intestinal segments with established the enteropathogenic character of strains e. coli, isolated from calves by means of enteritis. the enteropathogenic e. coli provoked dilatation of the ligated intestinal segments on the basis of the enterotoxin produced by them, whereas in the case of the non-enteropathogenic ones such a reaction was not observed. the dilated intestinal segments were filled with an exudate of watery consistency under pres ...19807010769
sensitivities of escherichia coli isolated from bovine and porcine enteric infections to antimicrobial antibiotics.the antibiotic sensitivities of escherichia coli isolated from 91 diarrheal pigs and 98 diarrheal calves were determined to 19 different microbials by the kirby-bauer method. virtually all e coli isolated from pigs and calves were sensitive to amikacin, colistin, gentamicin, and polymyxin b. in vitro minimum inhibitory concentrations for these 4 antibiotics were determined for isolates from both pigs and calves.19807011124
evidence of cytocidal effects of pasteurella haemolytica on bovine peripheral blood mononuclear leukocytes.pasteurella haemolytica had a pronounced cytocidal effect on bovine mononuclear leukocytes. mononuclear leukocytes separated from venous blood on ficoll-diatrizoate and incubated with either p haemolytica or escherichia coli showed a significantly greater percentage cell death than did cells incubated with staphylococcus epidermidis or controls. neither heat-killed nor x-irradiated p haemolytica caused a significant percentage cell death. the cytotoxic potential of p haemolytica was dose related ...19807013577
membrane filter contact technique for bacteriological sampling of moist surfaces.we used a membrane filter contact technique to pick up and grow bacteria from artificially contaminated surfaces. we were able to recover individual colony-forming units (cfu) of staphylococcus aureus from a moist agar surface more efficiently with 3- and 5- micron membrane filters than with rodac plates, velvet pads, velveteen pads, or smaller-pore membrane filters. the effective transfer of bacteria with the 3- and 5-micron membrane filters was 0.96 +/- 0.04 (standard error of the mean) and 0. ...19807014608
[enteropathogenicity of e. coli strains isolated from calves].by applying the technique of ligated intestinal segments, comparative studies were carried out on the enteropathogenic character of e. coli eliminated from calves. in was proved that the anatomic-topographic position of ligated intestinal segments, as well as the quantity of the innoculated bacterial suspension, exercise an influence on the intensity of intestinal reaction. the first 2.5 m and the last 4 m of the thin intestines are inappropriate for the investigation because of the spurious rea ...19807015684
the association of the o18, k1 and h7 antigens and the co1v plasmid of a strain of escherichia coli with its virulence and immunogenicity.from an o18ac:k1:h7 colv+ strain of escherichia coli (designated mw) that had caused meningitis in a human baby, mutant forms were isolated that lacked different combinations of its o, k and h antigens and its colv plasmid. these characters were also transmitted by conjugation to e. coli k12 and the virulence, immunogenicity and other properties of the different forms of both strains were studied. all the forms of the mw strain that lacked either the o18 or k1 antigens or the colv plasmid, but n ...19807021764
the efficacy of teat dips of differing persistence on teat skin in preventing intramammary infection by streptococcus uberis and escherichia coli in dry cows. 19807016251
purification of a low molecular weight non-histone chromosomal protein.a non-histone chromosomal proteins was extracted from rat liver chromatin with 0.35 m nacl and purified more than 2758 times to near homogeneity by hydroxyapatite, gel filtration, and phosphocellulose chromatography. the final fraction was greater than 95% pure as judged by non-denaturing gel electrophoresis. the protein, designated loosely bound non-histone chromosomal protein 1, had an observed molecular weight of 15 700. this protein was demonstrated to increase the amount of rna synthesized ...19807353013
diffusion-in-gel enzyme-linked immunosorbent assay (dig-elisa): optimal conditions for quantitation of antibodies.in the diffusion-in-gel enzyme-linked immunosorbent assay (dig-elisa) the quantitation of antibodies is based on their ability to form a diffusion gradient over an antigen-coated polystyrene surface. the antigen-antibody reaction is then visualized by an enzyme-conjugated anti-immunoglobulin. the enzyme-substrate reaction is finally performed by pouring a substrate-containing gel over the polystyrene surface. in this study with bovine serum albumin as antigen and a corresponding rabbit antiserum ...19807462651
evidence of species specificity in the cytocidal effects of pasteurella haemolytica.pasteurella haemolytica was found to have a cytotoxic effect on the peripheral blood mononuclear leukocytes of cattle, sheep, and goats, but no effect on the mononuclear leukocytes of swine, horses, or humans. in contrast, escherichia coli caused marked cell death among mononuclear leukocytes of all species tested.19807439998
superoxide dismutase from bacillus stearothermophilus. complete amino acid sequence of a manganese enzyme.superoxide dismutase from the thermophilic bacterium bacillus stearothermophilus is dimeric with a molecular weight of 45 487. it contains one atom manganese(iii) per dimeric molecule [brock, c. j., harris, j. i., & sato, s. (1976) j. mol. biol. 107, 175-178]. the subunits are identical, and the following primary structure comprising 203 amino acids has been determined: (formula: see text) the enzyme is identical in 60% of its residues with the escherichia coli b manganese enzyme [steinman, h. m ...19807397109
infectious bovine keratoconjunctivitis: effects of vaccination on moraxella bovis carrier state in cattle.a study was conducted to determine whether vaccination of cattle while they were undergoing an acute episode of infectious bovine keratoconjunctivitis (ibk), would cause vaccinated cattle to abort moraxella bovis infection sooner than nonvaccinated cattle. fourteen calves were allotted into two groups of seven calves each, and the eyes of each calf were exposed to a virulent culture of m bovis. twenty days after calves were infected and showing signs of ibk, seven calves were vaccinated with m b ...19807369598
occurrence of proteins immunoreactive with anti-coupling factor b in phosphorylating membrane preparations.coupling factor b has been isolated from beef heart mitochondria, apparently in multiple forms which differ in molecular weight and specific activity. since it has no known intrinsic catalytic activity, detection and quantitation have been based upon the factor b-dependent stimulation of atp-linked activities in factor b-deficient sub-mitochondrial particles. this communication reports the development of a reliable and more universally applicable enzyme-linked immunosorbent assay (elisa) for det ...19817284357
control of electron transfer in the cytochrome system of mitochondria by ph, transmembrane ph gradient and electrical potential. the cytochromes b-c segment.1. a study is presented of the effects of ph, transmembrane ph gradient and electrical potential on oxidoreductions of b and c cytochromes in ox heart mitochondria and 'inside-out' submitochondrial particles. 2. kinetic analysis shows that, in mitochondria at neutral ph, there is a restraint on the aerobic oxidation of cytochrome b566 with respect to cytochrome b562. valinomycin plus k+ accelerates cytochrome b566 oxidation and retards net oxidation of cytochrome b562. at alkaline ph the rate of ...19817305997
fluorescence-determined preferential binding of quinacrine to dna.quinacrine complexes with native dna (calf thymus, micrococcus lysodeikticus, escherichia coli, bacillus subtilis, and colstridium perfringens) and synthetic polynucleotides (poly(da) . poly(dt), poly[d(a-t)] . poly[d(a-t)], poly(dg) . poly(dc) and poly[d(g-c)] . poly[d(g-c)]) has been investigated in solution at 0.1 m nacl, 0.05 m tris hcl, 0.001 m edta, ph 7.5, at 20 degrees c. fluorescence excitation spectra of complexes with dye concentration d = 5-30 microm and dna phosphate concentration p ...19817326321
a survey of antibiotic resistance of escherichia coli isolated from farm animals in great britain from 1971 to 1977.a total of 94,827 escherichia coli strains isolated from cattle, sheep, pigs and poultry during the years 1971 to 1977 were tested for resistance to six antibiotics using a disc diffusion technique. the percentage of strains resistant to chloramphenicol (10 microgram), streptomycin (10 microgram), tetracycline (10 microgram), neomycin (10 microgram) and furazolidone (15) were 16.8, 53.9, 42.7, 18 and 10.9 per cent, respectively; 52.2 per cent of strains (1971 and 1972) were resistant to 2 microg ...19817020230
experimental intramammary infection of the dairy cow with escherichia coli during the nonlactating period.the nonlactating mammary gland was experimentally inoculated with escherichia coli. during the first half of the nonlactating period, 32% of 34 inoculated glands were temporarily infected. all intramammary infections were eradicated by the cow without therapy and no signs of mastitis were observed. during the 30 days before parturition occurred, 88% of 42 inoculated glands in the cows became infected. twenty-three intramammary infections were eradicated by the cow and infection in 14 glands pers ...19817020495
development of a radioimmunoassay for escherichia coli heat-stable enterotoxin: comparison with the suckling mouse bioassay.escherichia coli strains which produce heat-stable enterotoxin (st) are usually identified by demonstrating the production of st. at present, st can be detected only by bioassay methods. recently, we purified e. coli st, which enabled us to develop a radioimmunoassay for st. radioiodination of st was performed by the lactoperoxidase method, which resulted in a high specific activity and retained the biological activity of st. anti-st antisera were raised in goats by injecting the goats with pure ...19817021423
interactions of lipopolysaccharides, glycolipid, lipid a with acid soluble basement membrane collagen during thermal aggregation.lipopolysaccharides derived from a number of escherichia coli and salmonella species were incorporated into thermal aggregates acid soluble basement membrane collagens. although most of these endotoxins were noted to inhibit basement membrane collagen aggregation, some lipopolysaccharides possessed little or no inhibitory properties. however, the lipid a derived from all of the latter lipopolysaccharides and the glycolipid from salmonella minnesota r595 were noted to be significant inhibitors of ...19817049550
antagonistic reactions of the moulds from cattle-feeds in relation of staphylococcus aureus and escherichia coli, pathogenic to cattle. 19817024798
[ca antibodies (enterobacteriaceae common antigen) in the sera of domestic animals].using the indirect hemagglutination test, antibodies against enterobacteriaceae common antigen (ca) were tested in the sera of 123 horses, 142 cows, 108 sheep, 142 mature pigs and 60 piglets (3-4 weeks of age). anti ca antibody level and antibody titers for somatic antigens (phenol-water extracts) various serogroups of e. coli (0149, 0138, 0115, 078, 09) and s. typhimurium were compared. ca antibodies in titer equal or higher than 1:15 were found to occur in 100% of the examined horses and cows, ...19817029490
factors influencing the outcome of escherichia coli mastitis in the dairy cow.eight dairy cows at various stages of lactation were infected in a single mammary quarter with approximately 5 x 10(2) colony-forming units of serum-resistant escherichia coli. the severity of the mastitis which followed depended on the speed at which neutrophils were mobilised in the gland and the opsonic activity of the whey within the gland. newly calved cows tended to be refractory to the presence of irritants in the udder and hence were slow to mobilise defence mechanisms following infectio ...19817031811
[pathomorphology of gastroenteritis in newborn calves].the morphologic changes were studied in the parenchymal and digestive organs of a total of 39 calves with gastroenteritis from which pathogenic escherichia coli organisms were isolated. a correlation was established between the age of calves and the forms of gastroenteritis manifestation. in 1 to 3-day-old calves 63.6 per cent of the cases presented histologic changes of enteritis, and 36.3 per cent presented the septic form of the disease, while in 4 to 7 day-old calves these forms were present ...19817032052
intramolecular coupling of active sites in the pyruvate dehydrogenase multienzyme complexes from bacterial and mammalian sources.a simple method was developed for assessing the intramolecular coupling of active sites in the lipoate acetyltransferase (e2) component of the pyruvate dehydrogenase multienzyme complexes from escherichia coli, bacillus stearothermophilus and ox heart and pig heart mitochondria. samples of enzyme complex were prepared in which the pyruvate decarboxylase (e1) component was selectively and partly inhibited by treatment with increasing amounts of a transition-state analogue, thiamin thio-thiazolone ...19817032507
enzyme-linked immunosorbent assay for the quantitation of immunoglobulin g bound to escherichia coli.two strains of escherichia coli were opsonized by incubation in heat-inactivated bovine blood serum and in whey. the opsonized bacteria were then immobilized by complexing with anti-bovine antibodies previously coated to walls of polystyrene tubes. the amount of bovine immunoglobulin (ig) g in the immobilized complex was then determined by a direct enzyme-linked immunosorbent assay, using peroxidase as enzyme. thus, a direct measurement of one class of opsonic substances on the surface of the or ...19817034599
somatic and capsular factors of coliforms which affect resistance to bovine serum bactericidal activity.killing of bacteria which cause acute coliform mastitis was studied in vitro, using serum without exogenous complement. using 10% freshly collected whole serum, it was found that some strains were killed rapidly and could be classified as serum sensitive and others were killed less rapidly and could be classified as intermediate serum sensitive. with other strains, fewer were killed, and then the survivors multiplied; these could be classified as serum resistant. a 50-percentage kill of serum-re ...19817039431
assay of penetrability of bovine papillary duct implanted with escherichia coli endotoxin.a method has been developed to assay the relative penetrability to a solute of the papillary duct (streak canal) of the bovine teat. escherichia coli lipopolysaccharide endotoxin (1.0 microgram in 2.5 microliter of sterile distilled water) was implanted at a depth of 3 mm from the distal end (papillary orifice) of the papillary duct. if penetration by the irritant occurred after any one of 5 successive daily implantations, the inflammatory response of the mammary gland was detected by a precipit ...19817039434
production and evaluation of antibody to the heat-stable enterotoxin from a human strain of enterotoxigenic escherichia coli.escherichia coli heat-stable enterotoxin was coupled to bovine serum albumin by a carbodiimide reagent. antibody to the conjugate was produced by immunization of rabbits. data from radioimmunoassay and infant mouse tests indicate the presence of antibody to the enterotoxin. the antisera can be used in a radioimmunoassay to measure enterotoxin in various fluids.19817039508
the isolation of antibiotic resistant coliforms from meat and sewage.beef and pig carcases, meat products, frozen chickens, and sewage were examined in 3 separate surveys for antibiotic resistant coliforms. escherichia coli was isolated from 18 of 50 beef carcases; the numbers were low and resistance was found only to tetracycline. e. coli was isolated from 45 to 50 pig carcases; the numbers were high and showed a range of patterns of multiple antibiotic resistance. in meat products, the proportion of e. coli in contaminating organisms was low, and most resistanc ...19817016108
role of platelet serotonin in the canine pulmonary response to endotoxin.there is evidence suggesting a role for platelet serotonin (5-ht) in the immediate pulmonary response to endotoxin in the dog (j. appl. physiol. 23: 47, 1967). to further define this role, autologous canine platelets were labeled with 5-[14c]ht in vitro and then reinfused. subsequently escherichia coli endotoxin (0.55:b-5, difco), 2.5 mg/kg, was injected. within 5 min dynamic compliance (cl) fell by more than 50%, and nonelastic resistance (rl) increased by more than 200%. despite a 95% decrease ...19817009524
cyclic amp and permeability coefficient of albumin of the isolated rat mesentery. effects of escherichia coli endotoxin.we have investigated the mechanisms whereby escherichia coli endotoxin exerts its exudative effects, by using an isolated rat mesentery placed as a separation membrane between the two compartments of a diffusion cell. the permeability coefficient of albumin (pa) can be easily computed from the equilibration rate of 125i-labeled albumin added to one compartment. e. coli endotoxin increased pa in a concentration-related manner. direct measurements revealed an early and transient increase in cyclic ...19816261834
effects of bovine viral diarrhea virus infection on bovine polymorphonuclear leukocyte function.four procedures were used to evaluate the function of polymorphonuclear leukocytes (pmn) isolated from the blood of cattle experimentally infected with bovine viral diarrhea (bvd) virus: (1) uptake of am emulsion of paraffin oil and escherichia coli lipopolysaccharide, (2) nitroblue tetrazolium reduction, (3) chemiluminescence, and (4) iodination, or the conversion of iodide to a trichloroacetic acid-precipitable form. a marked impairment of iodination was consistently observed after infection w ...19816266288
adhesion of enterotoxigenic escherichia coli in humans and animals.enterotoxigenic escherichia coli (etec), an important cause of diarrhoea in humans and animal, require accessory virulence properties in addition to enterotoxin to manifest virulence. several classes of pili (hair-like protein surface organelles) promote adhesion of etec to small intestinal mucosa. antibody directed against adhesion pili interferes with colonization of the small intestine and prevents disease. this paper reviews studies with purified k88, k99 and 987 type pili used as parenteral ...19816114818
enzymatic mechanisms of dna repair.dna repair proficiency in cells is expressed by various enzymes which can recognize damaged sites arising from exogenous agents or endogenous conditions. either a damaged base is recognized by dna glycosylases, partially removed by hemi-dna glycosylases acting on diadduct damage, or direct incision of the phosphodiester bond near the damaged site. incision at those apurinic or apyrimidinic sites arising from depurination-depyrimidination or glycosylase reactions is effected by apurinic or apyrim ...19816281649
the evolution of alpha-fetoprotein and albumin. i. a comparison of the primary amino acid sequences of mammalian alpha-fetoprotein and albumin.the amino acid sequence of mouse alpha-fetoprotein has been deduced from the nucleotide sequence of its mrna and three chimeric plasmids containing overlapping segments of its cdna. a comparison of the amino acid sequence with that of either human and bovine albumin reveals in each case a 32% conservation of primary sequence. in addition, using the regularly spaced positions of cystine bridges, a 2-dimensional structure was generated, which revealed the presence of 3 closely related domains with ...19816161929
immunological properties of escherichia coli heat-stable enterotoxins: development of a radioimmunoassay specific for heat-stable enterotoxins with suckling mouse activity.antiserum was raised against the purified heat-stable enterotoxin (st) produced by enterotoxigenic escherichia coli strain 431, a class ii porcine enteropathogen. the antiserum was used to examine the antigenic determinants of sts produced by enterotoxigenic strains of different host origins and develop a sensitive radioimmunoassay specific for st having biological activity in suckling mice and piglets (sta). the antiserum neutralized one effective dose of toxin at a dilution of 1:5,000 and neut ...19816167519
bactericidal activity of bovine serum against escherichia coli isolated from the environment in 3 herds of dairy cows. 19816179401
synthesis of alpha- and beta-glycosides containing spin labels, as probes for studies of carbohydrate-protein interaction.nitroxide spin-labeled alpha-d-glycopyranosides were synthesized in good yield and in a highly stereoselective manner by reaction of per-o-benzyl-alpha-d-glycopyranosyl bromides with 2,2,6,6-tetramethyl-4-piperidinol under the bromide ion-catalyzed conditions devised by lemieux et al. after hydrogenolysis, the deblocked intermediates were oxidized to give the desired, spin-labeled alpha-d-glycopyranosides. nitroxide spin-labeled beta-d-glycopyranosides, as well as a beta-maltoside, were synthesi ...19816786748
bovine cryptosporidiosis: clinical and pathological findings in forty-two scouring neonatal calves.cryptosporidia organisms were identified in 42 of 161 (26%) neonatal, diarrheic calves, over a 32 month period commencing july 1979. forty of the 161 calves were submitted alive and cryptosporidiosis was diagnosed in 63% (25 of 40) of them. the cryptosporidia infected calves were usually one to two weeks old and came from 26 herds where the typical history was profuse, watery diarrhea in nearly all neonatal calves. the diarrhea usually started around one week of age, was unresponsive to all conv ...198217422204
identification of salmonellae of serogroup c1 by immunofluorescence and co-agglutination with antiserum against an oligosaccharide-protein conjugate.antiserum specific for salmonella o7 antigen raised by immunisation of rabbits with an artificial conjugate consisting of oligosaccharide and bovine serum albumin (os-bsa). the oligosaccharide was a pentasaccharide isolated after cleavage of the o antigen polysaccharide chain of salmonella thompson (o antigen 6, 7) with endo-glycanase from bacteriophage 14. the usefulness of the s. thompson os-bsa antiserum for rapid and accurate identification of isolates of salmonella of serogroup c1 (o6, 7) w ...19826183432
chemotactic requirements of bovine leukocytes.a system was described for studying bovine leukotaxis. chemotaxis was readily observed toward bovine serum activated by zymosan of agarose. however, bacterial culture filtrates and peptides, which were potent chemotaxins for leukocytes from other species, failed to affect bovine leukotaxis. using conditions suitable for studying binding to leukocytes from other species, specific binding of a radiolabeled chemotactic peptide to bovine leukocytes was not apparent. these data indicate that bovine l ...19826283962
comparison of paired whole milk and dried filter paper samples for anti-enterotoxin and anti-rotavirus activities.milk specimens, 75 from cows immunized against cholera toxin and 35 from a human population in which enterotoxigenic escherichia coli and rotaviral infections are endemic, were collected as paired filter paper and frozen whole milk samples. each pair was tested for antibody activity against heat-labile e. coli and vibrio cholerae enterotoxins. additionally, 12 of the 35 paired human milk samples stored as frozen whole milk and dried on filter paper were tested for anti-rotavirus immunoglobulin a ...19826286715
passive immunity in calf diarrhea: vaccination with k99 antigen of enterotoxigenic escherichia coli and rotavirus.twenty-four pregnant cows were vaccinated intramuscularly with k99 extract from enterotoxigenic escherichia coli and inactivated rotavirus as follows: six cows were injected with 2 ml of oil-adjuvanted vaccine; six cows were injected with 0.5 ml of oil-adjuvanted vaccine; six cows were injected with 4 ml of aluminum hydroxide-adjuvanted vaccine twice with a four-week interval; and six cows were unvaccinated as controls. calves born to these cows were challenged with enterotoxigenic e. coli at 6 ...19826288567
specific molecular activities of recombinant and hybrid leukocyte interferons.hybrid interferon dna recombinants were constructed from the iflra and iflrd leukocyte interferon-coding sequences. each of the hybrid interferons was purified with the use of a monoclonal antibody to human leukocyte interferon. three amino acid residues were identified, one or all of which function to potentiate antiviral activity on feline cells and reduce activity on human cells. because at sufficiently high concentrations human interferons can interact with mouse and rat receptors, it is app ...19826288687
biological activities and spectroscopic properties of chromophoric and fluorescent analogs of adenine nucleoside and nucleotides, 2',3'-o-(2,4,6-trinitrocyclohexadienylidene) adenosine derivatives.the ribose-modified chromophoric and fluorescent analog of atp 2',3'-o-(2,4,6-trinitrocyclohexadienylidene) adenosine 5'-triphosphate (tnp-atp) has been synthesized previously (hiratsuka, t., and uchida, k. (1973) biochim. biophys. acta 320, 635-647 and hiratsuka, t. (1976) biochim. biophys. acta 453, 293-297). in the present study, four tnp-derivatives of atp, adp, amp and adenosine were synthesized and compared for several chemical, spectral and enzymatic properties. their visible absorption a ...19826295507
expression of cloned calf prochymosin gene sequence in escherichia coli.an expression plasmid for calf prochymosin (prorennin) cdna was constructed. the plasmid (pcr301) contains the lacuv5 promoter in front of the fused gene in which the codons for the n-terminal four amino acids of prochymosin cdna were replaced with those for the n-terminal ten amino acids of beta-galactosidase. synthesis of the fused protein with the expected mr was detected immunologically in escherichia coli harboring pcr301. the product seemed to be localized in the cell membrane of the bacte ...19826295885
inactivation of spermidine n1-acetyltransferase with alkaline phosphatase.spermidine n1-acetyltransferase in an extract from phytohemagglutinin-stimulated bovine lymphocytes was inactivated by preincubation with alkaline phosphatase. inactivation of the acetylase with the phosphatase was totally inhibited by addition of pyrophosphate. these results suggest that spermidine n1-acetyltransferase, the rate-limiting enzyme in the biodegradative pathway of polyamines, is inactivated by dephosphorylation. a similar effect of alkaline phosphatase on the acetylase in an extrac ...19826297970
microbiological studies on hamburgers.one hundred and eighty-two raw, 112 pre-cooked and 750 cooked hamburgers composed mainly of beef or beef and pork were subjected to microbiological examination.raw hamburgers gave total bacterial counts from 10(6) to 10(8) per g, counts of enterobacteriaceae from 10(4) to 10(6) per g, of escherichia coli from 10(3) to 10(5), of group d streptococci from 10(2) to 10(4), of staphylococcus aureus from 3 to 10(2) and of clostridium perfringens less than 10 bacteria per g. of the samples, 32% contain ...19826276464
distantly related sequences in the alpha- and beta-subunits of atp synthase, myosin, kinases and other atp-requiring enzymes and a common nucleotide binding fold.the alpha- and beta-subunits of membrane-bound atp synthase complex bind atp and adp: beta contributes to catalytic sites, and alpha may be involved in regulation of atp synthase activity. the sequences of beta-subunits are highly conserved in escherichia coli and bovine mitochondria. also alpha and beta are weakly homologous to each other throughout most of their amino acid sequences, suggesting that they have common functions in catalysis. related sequences in both alpha and beta and in other ...19826329717
functional groups at the catalytic site of bf1 adenosinetriphosphatase from escherichia coli.the rates of inactivation of bf1 adenosinetriphosphatase (bf1-atpase) from escherichia coli by 7-chloro-4-nitro-2,1,3-benzoxadiazole, 1-fluoro-2,4-dinitrobenzene, 2,4,6-trinitrobenzenesulfonate, phenylglyoxal, and n,n'-dicyclohexylcarbodiimide have been measured in the presence and absence of various concentrations of inorganic phosphate, adp, atp, or magnesium ion. dissociation equilibrium constants and rate constants for the labeling reactions have been deduced from a quantitative treatment of ...19826462170
fluorogenic substrates for bacterial aminopeptidase p and its analogs detected in human serum and calf lung.a sensitive fluorimetric assay was developed for bacterial aminopeptidase p, based on intramolecularly quenched fluorogenic substrates. two substrates were synthesized. phe(no2)-pro-hn-ch2-ch2-nh-abz (substrate i) and phe(no2)-pro-pro-hn-ch2-ch2-nh-abz (substrate ii), in which the phe(no2) group (rho-nitro-l-phenylalanyl) quenches the fluorescence of the abz group (omicron-aminobenzoyl). both substrates were readily cleaved by aminopeptidase p from escherichia coli, releasing rho-nitro-l-phenyla ...19826749499
evaluation of immunological methods for detection of bovine growth hormone (bgh) produced in e. coli.the use of several immunological methods for studies on synthesis of bovine growth hormone (bgh) by e. coli is described here. the elisa procedure was shown to be the least sensitive and unfit for assaying bgh in e. coli extracts. the solid-phase radioimmunoassay (ria) proved to be highly sensitive, but since e. coli extract itself (not containing bgh) interfered with the immunological reaction, its use for measuring bgh was practically limited. the best adequate procedure proved to be radioimmu ...19826749998
inhibition of calf thymus dna polymerase alpha and of normal and cancer cell growth by butylanilinouracil and butylphenylguanine.6-(p-n-butylanilino)uracil and n2-(p-butylphenyl)guanine inhibited the activity of dna polymerase alpha from calf thymus but had no effect on other eukaryotic polymerases (dna polymerases beta and gamma) or escherichia coli dna polymerase i. inhibition was competitive with deoxyguanosine 5'-triphosphate and did not occur in the reaction of dna polymerase alpha with a template that did not contain cytosine residues. the results support a mechanism which involves hydrogen bonding of inhibitors wit ...19826756479
enhancement of the chemotactic response of bovine polymorphonuclear leukocytes by levamisole.the effects of levamisole on random migration, chemotaxis, phagocytosis, and intracellular killing by bovine polymorphonuclear leukocytes (pmn) were investigated. chemotactic assays were performed, using micropore filters in modified boyden chambers. phagocytosis and intracellular killing of escherichia coli were analyzed by standard viable bacterial counts. results indicated that levamisole enhanced the chemotactic response of pmn at concentrations ranging from 10(-4) to 5 x 10(-3)m. phagocytes ...19826762119
a mammalian dna polymerase alpha holoenzyme functioning on defined in vivo-like templates.in analogy to the escherichia coli replicative dna polymerase iii we define two forms of dna polymerase alpha: the core enzyme and the holoenzyme. the core enzyme is not able to elongate efficiently primed single-stranded dna templates, in contrast to the holoenzyme which functions well on in vivo-like template. using these criteria, we have identified and partially purified dna polymerase alpha holoenzyme from calf thymus and have compared it to the corresponding homogeneous dna polymerase alph ...19826765199
nucleotide sequence of calf prorennin cdna cloned in escherichia coli.the nucleotide sequence of prorennin (prochymosin) cdna cloned in e. coli was determined by the technique of maxam and gilbert. the longest prorennin cdna insert in ptacr1 contained the putative signal sequence and the coding sequence for the peptide from the 1st amino acid, ala (nh2 terminal), to the 296th, ser, and the other clone ptacr9 contained the coding sequence from the 258th, asp, to the 365th, ile (cooh terminal), and the tga termination codon followed by the 3'-untranslated region. th ...19826804449
antimicrobial characteristic of insoluble alkylpyridinium iodide.insoluble and soluble alkylpyridinium iodides (c8 to c18) were synthesized. the insoluble agents were quaternized 4-vinylpyridine-divinylbenzene copolymers. the insoluble agent [c12(50)] that contained 50% divinylbenzene and had a c12 alkyl chain was selected as the most suitable insoluble agent. c12(50) showed poor durability of the antibacterial activity, but c12(50), which had lost the activity, was refreshed by washing with ethanol. this washing became ineffective after a few cycles of antib ...19826808918
fidelity in transcription assessed by dna-dependent rna polymerases.the use of in vitro transcription of polynucleotides by prokaryotic and eukaryotic dna-dependent rna polymerases has proven of great usefulness in detecting mutagenic base modifications. quite similar results are obtained with ribo- and deoxyribopolymers as templates, and with mg2+ and mn2+ at optimal concentrations. recent studies have centered on polymers containing etheno c, as well as its hydrated form. these modifications are of particular interest, since they are the consequence of metabol ...19826814508
chemotactic factors for bovine leukocytes.an agarose method was used to determine the nature of chemotaxins for bovine leukocytes as related to coliform mastitis. freshly collected bovine serum or plasma was frequently chemotactic, probably due to spontaneous complement activation. fresh serum was always rendered chemotactic when activated with zymosan or when heat-killed or viable coliform bacteria were incubated in the serum. the bacteria did not contribute to preexisting activity in the serum. escherichia coli grown in synthetic medi ...19826816108
inhibition of dna polymerase by captan.captan inhibits dna polymerases of both eukaryotic and prokaryotic sources. when polymerases were employed in assays with various nucleotides as template-primer, no specificity in the base sequence of polynucleotide was required for inhibition. sucrose gradient centrifugation and preincubation studies showed the inhibition was caused by an irreversible alteration of the polymerase. captan and dna compete for the same site on the polymerase, thus dna can serve a protective role in the elimination ...19827039680
plasma zinc and iron concentrations as measurements for evaluating the influence of endotoxin-neutralizing agents in escherichia coli endotoxin-induced mastitis.the influence of bacterial lipopolysaccharides on plasma zn and fe concentrations and the endotoxin-neutralizing capacity of polymyxin b was studied in 3 dairy cows. also, the feasibility of using plasma zn and fe concentrations as measurements for evaluating the influence of endotoxin-neutralizing agents in escherichia coli endotoxin-induced mastitis was studied. a positive relationship was ascertained between the dose of endotoxin given intramammarily (imm) and the effect on mean values of pla ...19827041717
inhibition of k99 antigen synthesis by l-alanine enterotoxigenic escherichia coli.the effect of various culture media on k99 antigen production by enterotoxigenic escherichia coli strains of bovine origin was investigated by slide agglutination tests, enzyme-linked immunosorbent assays and in vitro attachment to intestinal villi. a-alanine at concentrations higher than 0.7 g 1(-1) was responsible for the inhibition of k99 synthesis observed on media rich in amino acids. the increased inhibitory activity of l-alanine in glucose-rich media after autoclaving suggested the format ...19827042906
glutaredoxin from calf thymus. purification to homogeneity.the protein glutaredoxin, required for gsh-dependent ribonucleotide reduction, has been purified to homogeneity from calf thymus. the preparative method consisted of ammonium sulfate precipitation and three chromatography steps on deae-cellulose, sephadex g-50, and cm-sepharose. calf thymus glutaredoxin was assayed on the basis of its inherent gsh-disulfide transhydrogenase activity. glutaredoxin, purified 3000-fold was demonstrated to be homogeneous by polyacrylamide gel electrophoresis and hig ...19827045093
the biotyping of escherichia coli isolated from healthy farm animals.a total of 2973 escherichia coli, isolated from six different groups of animals, were examined for their ability to ferment adonitol, dulcitol, raffinose, rhamnose and sorbose in solid media. twenty-nine fermentation patterns were recorded although 2443 (82%) of the e. coli belonged to seven of the 32 possible biotypes. ninety-six o-serotypes were identified within the 2973 e. coli. the number of o-serotypes represented in the 15 most common biotypes ranged from three to 15. serotypes o8 and o9 ...19827045219
scanning and transmission electron microscopic study of the small intestine of colostrum-fed calves infected with selected strains of escherichia coli.colostrum-fed calves were fed milk replacer containing 10(11) enteropathogenic escherichia coli (eec) or nonenteropathogenic e coli (neec). the neec failed to colonize the small intestine or to be associated with the intestinal wall. the eec colonized the middle and caudal portions of the small intestine, and in these areas, 80% of the organisms were associated with the intestinal wall. light, immunofluorescence, scanning, and transmission electron microscopic studies demonstrated a layer of eec ...19827046530
electrical conductivity of milk for detection of mastitis.the potential value of electrical conductivity of milk as a screening test for subclinical mastitis was evaluated. conductivity of foremilk and of postmilking strippings from 368 quarters of 92 cows was measured. infection status of quarters was determined by bacteriological analysis of strict foremilk samples. infections were classified as by primary or secondary pathogens, depending on the importance of the isolated organism as a mastitis pathogen. somatic cells were counted on foremilk sample ...19827047600
effects of dietary milk fat (whole milk) and propionic acid on intestinal coliforms and lactobacilli in calves.calves fed whole milk had 2,000-fold fewer (p less than 0.001) coliforms in the cranial part of the small intestine than did calves fed skim milk (fat removed). calves fed milk with 32 mm added propionic acid had nearly 1,000-fold lower (p less than 0.001) counts of lactobacilli in the entire gastrointestinal tract than did calves fed milk without added propionic acid.19827049020
alkaline opening of imidazole ring of 7-methylguanosine. 1. analysis of the resulting pyrimidine derivatives.column chromatography and spectroscopy have been employed in analyzing pyrimidine derivatives obtained from alkaline-treated 7-methylguanosine (7-meguo). high performance liquid chromatography (hplc) revealed that the alkaline generated products consist predominantly of two forms of ring opened 7-methylguanine (rom7gua) in equal amounts. material from both dowex 50 and sephadex lh-20 columns was readily resolvable into two hplc peaks. the species in one peak appears to be composed of formylated ...19827049418
role of lymphatic vessels in bacterial clearance from early soft-tissue infection.a popular concept regarding the pathophysiologic characteristics of infection is that early bacterial clearance from tissue is an important host defense mechanism. staphylococcus aureus, s epidermidis, escherichia coli, enterococcus, and klebsiella pneumoniae were radiolabeled with tritiated thymidine and injected subcutaneously into rabbit ears. negligible clearance occurred at five hours, and less than 30% of injected bacteria cleared in 24 hours. lymphatic function measured by clearance with ...19827034674
bovine mastitis: antimicrobial resistance patterns.resistance to 15 antimicrobials was determined for klebsiella spp, escherichia coli, and staphylococcus aureus in 302, 370, and 344 samples. respectively, from cases of bovine mastitis, the degree of association of resistance for all 2-way combinations of antimicrobials was calculated for each organism. significantly high and low associations were reported. an association greater than 1 indicated an increased probability of resistance to the 2nd antimicrobial of a 2-way combination, whereas an a ...19827037719
bovine mammary involution following intramammary infusion on colchicine and endotoxin at drying off.effects of intramammary infusion of colchicine, endotoxin, and colchicine in combination with endotoxin on mammary involution were studied on 25 dairy cows in late lactation. both quarters of right udder halves were infused at or near drying off while left udder halves received no infusion. samples of mammary secretion were obtained 1 day prior to drying off, at drying off, and .5, 1, 2, 3, and 7 days post drying off. mammary secretion obtained during the early dry period from udder halves infus ...19827050191
infectious agents associated with neonatal calf disease in southwestern idaho and eastern oregon.over a 2-year period, 296 episodes of disease involving 226 1-to-60-day-old calves were referred to the caldwell veterinary teaching center. infectious disease agents were found in 96% of the cases. salmonella spp were the most frequently isolated agents from dairy calves, whereas coronavirus was the agent most commonly associated with diarrhea in beef calves. multiple agents were found in 20% of the dairy calves and in 12% of the beef calves. salmonella dublin, which is associated with severe d ...19827085442
the immunosuppressive effects of trichothecenes and cyclochlorotine on the antibody responses in guinea pigs.immunosuppressive effects of trichothecenes of fusarium solani and fusarium nivale, t-2 toxin and fusarenon-x, and also of a mycotoxin of penicillium islandicum, cyclochlorotine, were studied by measuring the anti-2,4-dinitrophenyl (dnp) antibody responses in guinea pigs immunized with dnp-bovine serum albumin. among these mycotoxins, t-2 toxin alone suppressed strongly the anti-dnp antibody responses at a certain sublethal dose. with other mycotoxins, no effect was observed at any sublethal dos ...19827120038
kinetics of cytochrome b oxidation in antimycin-treated submitochondrial particles.it has been shown that in bovine heart submitochondrial particles, antimycin and 2-heptyl-4-hydroxyquinoline n-oxide (hqno) inhibit the oxidation of nadh, succinate, and reduced ubiquinone incompletely, the uninhibited rate being about 20-40 nmol of substrate oxidized min-1 (mg of protein)-1. by contrast, rotenone, cyanide, bal (2,3-dimercaptopropanol), and 5-n-undecyl-6-hydroxy-4,7-dioxobenzothiazole [trumpower, b. l., & haggerty, j. g. (1980) j. bioenerg. biomembr. 12, 151-164] caused essentia ...19827150580
incidence and treatments of postpartum reproductive problems in a dairy herd.incidence of assisted births, retained fetal membranes (rfm), and metritis were recorded in one hundred dairy cows from parturition through 14 days post-calving. manual removal of rfm was not attempted. all rfm were excised inside the vulva and observations of natural rfm expulsion were recorded. fifteen of 100 cows (15%) had assisted births, 27 (27%) had rfm, 8 (8%) had primary metritis not associated with other postpartum reproductive problems, and 26 (26%) had secondary metritis. uterine swab ...198216725716
an enzymatically active antigen-antibody probe to measure circulating immune complexes. ii. e. coli beta-galactosidase in the probe and c1q as the recognition unit.an enzymatically active probe (beta-galactosidase-anti-beta-galactosidase complex) is used to measure circulating immune complexes (cic), in a competition assay where probe and cic are confronted with a 'recognition unit'. the latter is bovine conglutinin in the original description of this method. here we describe a version utilizing human or bovine c1q. the two techniques are compared for their sensitivity and specificity, on both in vitro formed tetanus toxoid-anti-toxoid complexes and on ser ...19836404986
lipopolysaccharide-mediated bovine endothelial cell injury in vitro.lipopolysaccharide (lps) produced time- and dose-dependent bovine endothelial cell injury in vitro that was manifested initially by cell detachment from culture substrate with subsequent cell lysis. bovine endothelial cell injury was observed with lps derived from salmonella minnesota r595, a lps comprised only of lipid a and a trisaccharide core, as well as intact lps preparations derived escherichia coli and s. typhosa. lps-mediated bovine endothelial cell detachment was prevented by incubatio ...19836827807
why are two different types of pyridine nucleotide transhydrogenase found in living organisms?two types of pyridine nucleotide transhydrogenases have been reported in living organisms. the energy-linked transhydrogenase is found in mitochondria and in certain heterotrophic and photosynthesizing bacteria, while the non-energy-linked transhydrogenase is found in certain heterotrophic bacteria. the presence of a structurally similar non-energy-linked transhydrogenase in azotobacter vinelandii, pseudomonas aeruginosa and pseudomonas fluorescens is readily shown in extracts from these bacteri ...19836840064
cross-reactivity of haemophilus somnus antibody in agglutination and complement fixation tests and in the enzyme-linked immunosorbent assay.the specificity and sensitivity of agglutination, complement fixation, and enzyme-linked immunosorbent assay (elisa) procedures in the detection of antibodies to haemophilus somnus was investigated. h. somnus rabbit immune sera were found to agglutinate pasteurella multocida, staphylococcus aureus, and haemophilus agni and, in some instances, also pasteurella haemolytica, salmonella dublin, streptococcus agalactiae, and corynebacterium pyogenes. in complement fixation tests with saline extracts ...19836841584
concentrations of methicillin in blood, normal milk and mastitic milk of cows after intramuscular injection of methicillin and tamethicillin.tamethicillin (tam) is a basic ester pro-drug of methicillin (met) which is converted in the body by non-specific esterases to met. equal doses of met and tam were administered intramuscularly in a crossover trial involving four dairy cows. acute mastitis was induced in each cow by infusing two quarters of the udder with escherichia coli endotoxin 3 h before antibiotic administration. peak serum met concentrations after met injection were significantly (p less than 0.001) higher than peak serum ...19836854731
[intrauterine bacterial and mycotic infections in cows].bacteriologic, mycologic, and serologic investigations of cows and calves and three experiments with rabbits were carried out to shed light on the bacteriology and mycology of the intrauterine infections in cows. the following organisms were isolated from the investigated cows that exhibited disturbances in their reproduction, and had abortions, or gave birth to calves that were affected with diseases or died: escherichia coli (17.84%), association of bacteria (7.64%); vibrio genitalis (3.86%); ...19836880018
urea--dna glycosylase in mammalian cells.urea-dna glycosylase, an enzyme presumed to be active in the repair of dna damage caused by oxidizing agents, has been identified previously in escherichia coli. this enzyme has now been shown to be present in cell extracts of calf thymus and human fibroblasts. it catalyzes the release of free urea from a double-stranded polydeoxyribonucleotide containing thymine residues fragmented by kmno4 and naoh treatment. the calf thymus enzyme has been 400-fold purified and largely separated from previous ...19836626501
tetrahydrobiopterin is synthesized by separate pathways from dihydroneopterin triphosphate and from sepiapterin in adrenal medulla preparations.using escherichia coli guanosine triphosphate cyclohydrolase, dihydroneopterin triphosphate was synthesized from guanosine triphosphate and was compared with sepiapterin as a substrate for tetrahydrobiopterin formation in bovine adrenal medulla extracts. the dihydrofolate reductase inhibitor, methotrexate, blocks the formation of tetrahydrobiopterin from sepiapterin but not from dihydroneopterin triphosphate. reduced nicotinamide adenine dinucleotide phosphate and a divalent metal ion are requir ...19836639080
chemical and immunological properties of escherichia coli heat-stable enterotoxin.five heat-stable enterotoxins (sts) produced by enterotoxigenic e. coli (etec) strains of porcine, bovine and human origin have been purified to apparent homogeneity. the sts with biological activity in suckling mice and piglets (sta) contained 18 amino acid residues, 10 or 11 different amino acids with a high proportion of acidic amino acids and 6 half-cystines. all 5 purified preparations were heat-stable, not denatured by organic solvents and detergents, resisted protease digestion and treatm ...19836686335
study of several factors affecting the agglutinating activity of k99-positive escherichia coli strains.the effect of several factors on escherichia coli k99-plasmid associated agglutination has been studied. the results obtained indicate that escherichia coli 637 (k99+) mediated red blood cell agglutination is unspecific although the agglutination titres for several erythrocyte species are significantly different. the agglutination is highly stable (at least with sheep red blood cells) to changes in temperature (from 4 degrees c to 37 degrees c), to changes in ph (from 5 to 9) and to the presence ...19836371953
hydrogen peroxide-mediated antagonism against serratia marcescens by streptococcus mitis.the alpha-hemolytic streptococcus mitis strain no. 17-1, isolated from the oral cavity of an healthy female adult, antagonized the growth of all 24 test strains of serratia marcescens examined; furthermore, this strain inhibited the growth of various strains of staphylococcus aureus, s. epidermidis, streptococcus pyogenes, s. agalactiae, s. pneumoniae, haemophilus influenzae, listeria monocytogenes, and corynebacterium diphtheriae. however, strans of escherichia coli, enterobacter cloacae, klebs ...19836372321
[effect of orally administered bovine lactoferrin and bovine igg on the establishment of escherichia coli in the digestive tract of gnotobiotic mice and human newborn infants].the bacteriostatic effect of the association bovine lactoferrin (lf) and bovine igg (igg) was studied in vitro and in vivo against two escherichia coli strains, s17 and emo1, isolated from the faecal flora of mouse and man, respectively. these two strains were sensitive in vitro to the bacteriostatic effect of lf + igg. a kinetic study of the in vivo establishment of e. coli s17 was followed in axenic mice associated with that strain. seven hours after inoculation, no difference was observed in ...19836372577
drug resistance and conjugative r plasmids in fecal escherichia coli strains isolated from healthy younger animals (chickens, piglets, calves) and children.a total of 11,777 escherichia coli strains were isolated from 90 chickens, 103 piglets, 96 calves, and 104 children in 1979 in gunma prefecture and tested for drug resistance and the presence of conjugative r plasmids. the percentages of individuals that excreted drug-resistant strains were: chickens, 100%; piglets, 99%; calves, 100%; and children, 64%. the frequency of isolation of drug-resistant strains among the total isolates was: chickens, 98%; piglets, 93%; calves, 94%; and children, 41%. ...19836374389
infection with enterotoxigenic escherichia coli in calves and protection of the calves by vaccination of the dams.a report is given of a study on the occurrence of enterotoxigenic escherichia coli in calves in denmark. samples from 1379 1-30-day-old calves were examined and etec were isolated from 228 samples (16.5%). while in 1-2-day-old calves nearly one half (47.5%) harboured etec, the frequency dropped to 3.4% in 8-day-old calves, and of 165 9-30-day-old calves just one was found to harbour etec. a field trial with k99-containing bacterins was performed in 14 herds with etec problems. a total of 109 cow ...19836375531
protection against acute, ascending pyelonephritis caused by escherichia coli in rats, using isolated capsular antigen conjugated to bovine serum albumin.we found that isolated escherichia coli k13 antigen conjugated to bovine serum albumin, in contrast to isolated, non-conjugated k13, was highly immunogenic and induced protection against acute pyelonephritis caused by e. coli o6k13h1 in rats.19836337094
relationship between penetrability of the papillary duct (teat) and phagocytic capability in lactating dairy cows.to determine whether there is a reciprocal relationship between penetrability of the papillary duct of the teat (streak canal) and phagocytic capability, 3 cows with highly penetrable papillary ducts and 3 with ducts highly resistant against penetration were identified, using a penetrability assay. leukocytes harvested from milk from these cows were tested for their capability to phagocytose staphylococcus aureus. phagocytic capability was found to be independent of the ability of microorganisms ...19836338773
cellular uptake and inhibition of dna synthesis by dihydroxyanthraquinone and two analogues.three analogues of aminoalkylamino-substituted anthraquinone derivatives, namely, 1,4-dihydroxy-5,8-bis(((2-[(2-hydroxyethyl)amino]ethyl)amino))-9,10-anthracenedione (dhaq), 1-hydroxy-5,8-bis(((2-[(2-hydroxyethyl)amino]ethyl)amino))-9,10-anthracenedione (haq), and 1,4-bis(((2-[(2-hydroxyethyl)amino]ethyl)amino))-9,10-anthracenedione (aq), were chosen with respect to the number of hydroxyl groups on the aromatic ring. dhaq showed about 100 times more potent antiproliferative activity on cultured ...19836339045
depression of b-lymphocytes by mastitis and treatment with levamisole.proportion of b-lymphocytes in milk and blood decreased simultaneously with development of mastitis induced with endotoxin and recovered with disappearance of clinical signs. however, the change in t-lymphocytes was slight. the reduced percentage of b-lymphocytes was caused by reduction in absolute number of such cells. when used orally, levamisole increased the proportion b-lymphocytes of milk to the same as or more than that of similar cells in peripheral blood. this compound may enhance activ ...19836341425
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