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631.
Cloning and purification of the Streptococcus suis serotype 2 glyceraldehyde-3-phosphate dehydrogenase and its involvement as an adhesin 总被引:8,自引:0,他引:8
Streptococcus suis serotype 2 is a swine pathogen responsible for diverse diseases and may be present in the tonsils of pigs which show no sign of illness. Because adhesion to host cells may be important in the carrier state, this study was undertaken to characterize a 39 kDa surface protein identified as a glyceraldehyde-3-phosphate dehydrogenase (GAPDH), possibly implicated in the adhesion of the bacteria. The gene encoding for the GAPDH of S. suis was cloned and sequenced. The DNA sequence contained an open reading frame encoding for a 336 amino acid polypeptide exhibiting 95% sequence identity with the GAPDH from Streptococcus pyogenes and from other streptococci. Using the Qiaexpress expression plasmids, the gapdh gene was inducibly overexpressed in E. coli to produce GAPDH with a hexahistidyl N-terminus to permit its purification. The (His)6GAPDH protein was found to possess functional GAPDH enzymatic activity after the purification. An adherence assay with S. suis and porcine tracheal rings pre-incubated with (His)6GAPDH and non-incubated rings was showed a significant reduction in the adhesion of S. suis in the (His)6GAPDH pre-incubated rings compared to the non-incubated rings. The GAPDH protein of S. suis seems to be involved in the first steps of the bacterial adhesion to host cells. 相似文献
632.
Kaskous S Gottschalk J Hippel T Grün E 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(3-4):108-116
In 11 Awassi ewes of a flock of 30 animals continuous investigations were carried out on the changes of somatogenic (growth hormone-GH, prolactin-PRL, insulin-like growth factor I-IGF-I) and steroid hormones (progesterone--PG, estradiol-17 beta-E2) in blood plasma during a gestation period. Eight animals were pregnant (3 with twins), 3 non-pregnant ewes served as control animals. Pregnancy is associated with an increase in the concentrations of the steroid hormones in blood plasma, they decrease markedly already prepartal (PG) or directly at term (E2), reflecting the placental origin of both hormones. Ewes with twins have higher concentrations of both steroid hormones in their blood plasma than animals with a single fetus. During pregnancy the concentrations of IGF-I in blood plasma increase continuously and normalize rapidly after birth. The relationship between the duration of the pregnancy and the concentration of IGF-I can be described by a quadratic regression, further positive correlations exist between the concentrations of IGF-I and PG or E2 in blood plasma, but a negative correlation between IGF-I and PRL. The concentration of PRL diminishes during the gestation, which reflects increasing seasonal influences (decreasing day length and environmental temperature). The concentration of GH shows a steady level throughout the gestation period. Both hormones increase markedly at term, which represents an attendant circumstance of the birth. From all hormones investigated in blood plasma of the ewes only the concentration of IGF-I exhibits a strong positive correlation with the birth weight of their lambs. This can be taken as a first hint to the ability of IGF-I to promote directly the fetal growth. 相似文献
633.
The ischiorectal fossa: an alternative route for the administration of prostaglandin in cattle 下载免费PDF全文
Colazo MG Martínez MF Kastelic JP Mapletoft RJ Carruthers TD 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(7):535-541
Three experiments were conducted to investigate the ischiorectal fossa (IRF) as a route for the administration of prostaglandin F2 alpha (dinoprost) in cattle. In Experiment 1, 21 nonlactating Holstein cows were given 100 micrograms of gonadotropin releasing hormone (GnRH), intramuscularly (i.m.), and, 7 d later, 25 mg of dinoprost into the IRF. Sixteen cows had serum progesterone concentrations > or = 1.0 ng/mL at the time of dinoprost treatment, and all of these had rapid and complete luteolysis; the other 5 cows were not considered to have a functional corpus luteum (CL) at the time of treatment. There were minimal adverse behavioral reactions to the IRF injections and no visible or palpable tissue reactions at the injection site. In Experiment 2, 74 Holstein heifers were given 25 mg of dinoprost by IRF injection. Luteolysis occurred in 84.3% of the heifers with a functional CL (as determined by the serum progesterone concentration at the time of treatment). Of the heifers bred by either natural service or artificial insemination, 61.8% became pregnant. In Experiment 3, 48 beef heifers received dinoprost 7 d after ovulation, as follows: 25 mg, i.m. (n = 9); 25 mg, IRF (n = 10); 10 mg, IRF (n = 10); 10 mg, subcutaneously (s.c.) (n = 10); or 10 mg, intravulvosubmucosally (IVSM) (n = 9). Fewer heifers (P < 0.05) were found to be in estrus or ovulating in the 10 mg IVSM group (0% and 11%, respectively) than in the 25 mg i.m. group (100% and 100%), the 25 mg IRF group (90% and 100%, respectively), or the 10 mg IRF group (80% and 80%). The rates of estrus (50%) and ovulation (50%) were intermediate in the 10 mg s.c. group. In summary, 25 mg of dinoprost injected into the IRF caused minimal behavioral or tissue response and induced luteolysis and fertile estrus. In addition, 10 mg of dinoprost injected into the IRF was as efficacious as 25 mg given either i.m. or into the IRF in inducing estrus and ovulation. 相似文献
634.
Clonal relationships among avian Escherichia coli isolates determined by enterobacterial repetitive intergenic consensus (ERIC)-PCR 总被引:1,自引:0,他引:1
da Silveira WD Ferreira A Lancellotti M Barbosa IA Leite DS de Castro AF Brocchi M 《Veterinary microbiology》2002,89(4):323-328
Forty-nine avian Escherichia coli isolates isolated from different outbreak cases of septicemia (24 isolates), swollen head syndrome (14 isolates) and omphalitis (11 isolates), and 30 commensal isolates isolated from poultry with no signs of illness were characterized by enterobacterial repetitive intergenic consensus (ERIC)-PCR technique and their serotypes were determined. The ERIC-PCR profile allowed the typing of the 79 isolates into 68 ERIC-types and grouped the isolates into four main clusters (A-D), with the omphalitis isolates being grouped with the commensals and separated from the septicaemia and swollen head syndrome. These results indicate that ERIC-PCR is a technique that could replace other molecular characterization techniques such as random amplification of polymorphic DNA (RAPD)-PCR and restriction fragment length polymorphism (RFLP), reinforce previous observations that omphalitis isolates are just opportunistic agents, and are consistent with many reports that specific genotypes are responsible for causing specific diseases. Most of the isolates were either nontypable or rough, supporting the need for alternative methods for typing these isolates. 相似文献
635.
Prange H Jonas K Gottschalk C Discher U Ribbeck E Mewes W 《Berliner und Münchener tier?rztliche Wochenschrift》2000,113(7-8):289-294
Out of a nonbreeding group of cranes, 10 birds died peracutely at the end of April 1998. The pathological investigation showed changes in the intestine, liver and kidneys caused probably by an intoxication; but corresponding analyses did not result in a specified poison. The proof of E. coli, Cl. perfringens and Campylobacter jejuni is to be interpreted as a subordinate result. 7 of 8 cranes had a low to high infestation with endoparasites (Porrocaeum spp., Eimeria pusilla, Echinostoma spp.). 5 of 8 birds showed leaness, possibly as a result of the migration exertion. Further on, the analysis results of a 9th crane found at another place are included in this paper. 相似文献
636.
637.
马光庭 《广西农业生物科学》1994,(3)
本文介绍从德国哥廷根污水处理厂腐化塔污泥中分离出的两株甲烷细菌,其中一株为甲酸甲烷杆菌(Methanobacteriumformicicum),其细胞杆状,可利用甲酸或H2/CO2作为碳源和能源,另一株为甲烷八叠球菌属(Methanosarcina),其细胞球状,成堆排列,可利用甲醇或H2/CO2作为碳源和能源。 相似文献
638.
R Higgins M Gottschalk K R Mittal M Beaudoin 《Canadian journal of veterinary research》1990,54(1):170-173
A total of 349 isolates of Streptococcus suis retrieved from different tissues from diseased pigs were examined in this study. Only 48% of them could be categorized as one of serotypes 1 to 8 and 1/2. Among typable isolates, serotype 2 was the most prevalent (23%), followed by serotype 3 (10%). The majority of all isolates originated from lungs, meninges/brain, and multiple tissues. Forty-one percent of typable isolates and 33% of untypable isolates were retrieved in pure culture. Other isolates were found in conjunction with Pasteurella multocida, Escherichia coli, Actinobacillus pleuropneumoniae, Actinomyces pyogenes, and other streptococci. Typable S. suis isolates were more frequently isolated from pigs between five and ten weeks of age, while untypable isolates were mostly found in animals aged more than 24 weeks. No obvious monthly and/or seasonal variation of the prevalence of isolation of S. suis could be detected. 相似文献
639.
Assessment of the efficacy of tilmicosin phosphate to eliminate Actinobacillus pleuropneumoniae from carrier pigs 总被引:3,自引:0,他引:3 下载免费PDF全文
N. Fittipaldi C. Klopfenstein M. Gottschalk A. Broes M.A. Paradis C.P. Dick 《Canadian journal of veterinary research》2005,69(2):146-150
The aim of this study was to evaluate the efficacy of in-feed medication with tilmicosin phosphate in order to eliminate or reduce the carriage of Actinobacillus pleuropneumoniae in the tonsils of carrier pigs. Two groups of 6 carrier animals received either a non-medicated feed (control group) or feed medicated with 400 ppm of tilmicosin phosphate (treated group) for 30 d. Three sentinel pigs were then introduced in each group and left for 29 d. The presence of A. pleuropneumoniae in tonsils was monitored using several techniques, including polymerase chain reaction (PCR). At the end of the treatment all of the control animals, but only 1 treated pig, were positive by PCR from tonsillar surface material. However, at necropsy, all control and most treated animals, as well as 1 sentinel animal, in both groups were positive by PCR from whole tonsils. In conclusion, under the experimental conditions, in-feed treatment with 400 ppm of tilmicosin phosphate significantly reduced the presence of A. pleuropneumoniae on the surface of tonsils but was unable to completely eliminate the organism from deeper tonsillar tissues and to prevent bacterial shedding by carrier animals. 相似文献
640.