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1.
K Shinagawa S Otake N Matsusaka S Sugii 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(3):443-446
Vacuole response in HEp-2 cells was induced with culture supernatants of Bacillus cereus strains isolated from outbreaks of vomiting- and diarrheal-type food poisoning grown in rice flour and laboratory media. High vacuole response was obtained with culture supernatants of B. cereus strains isolated from vomiting-type food poisoning grown in cooked rice suspension or on a cooked rice plate, whereas no response was obtained with those of the same strains grown in brain heart infusion and trypto-soya broth media. The vacuole activity appeared only after spore formation of B. cereus. The activity was stable to proteolytic enzymes, heating, and exposing to pH 2.0 and 11.0. Of 124 strains isolated from B. cereus food poisoning that were tested, the vacuole activity was observed by 68 of 110 (61.8%) of the strains isolated from the vomiting-type food poisoning but not by all strains (14 strains) from diarrheal-type ones. Moreover, the vacuole response in the HEp-2 cells was found to be induced by 56 of 76 (73.7%) of the serotype H-1 strains isolated from vomiting-type food poisoning. 相似文献
2.
Of 42 strains of Pasteurella meltocida isolated from different outbreaks of hemorrhagic septicaemia and from healthy cattle in various parts of the Suden, 38 belonged to Carters' type B and four to type E. The strain used for vaccine production was type E. With respect to somatic antigen determination, there was some correlation between the results of the gel diffusion and the agglutination tests as most strains reacted with 0 groups 6 antisera in both tests. However, some antigens cross-reacted with antisera of different 0 groups in the gel diffusion test. No correlation was observed between the pattern of biochemical reactions and the serological types. 相似文献
3.
蜡样芽孢杆菌是一种可引起食物中毒的常见食源性细菌,属于革兰氏阳性的条件致病菌,广泛存在于土壤、空气、水及植物源、动物源加工的食品中。近年发现也能感染包括人在内的多种动物,是一种人兽共患性细菌,特别是能够引起人畜肠道疾病,导致腹泻型或呕吐型食物中毒。快速准确检测蜡样芽孢杆菌是控制其污染和感染后治疗的关键环节。作者对蜡样芽孢杆菌的检测方法进行了全面详细的总结,主要包括传统检测方法、普通PCR、多重PCR（mPCR）、实时荧光定量PCR（Real-time PCR）、叠氮溴化丙锭-定量PCR（PMA-qPCR）、微滴数字PCR技术（ddPCR）、环介导等温扩增（LAMP）及酶联免疫吸附测定（ELISA）。从传统方法到新兴技术,涉及传统检测技术、分子生物学检测和免疫学检测技术,作者主要总结了各方法的原理、检测范围,并对各方法的优缺点进行了比较。这些检测方法的灵敏度、精确度、样本要求等有所不同,可根据检测需要和条件限制进行选择。将分子生物学方法和免疫学等方法有效地结合起来,多角度多层次地对样品进行检测,可全面而准确地呈现检测结果。蜡样芽孢杆菌能产生多种毒素,这些毒素决定了其致病性,所以除了检测菌体外,还可以对毒素进行检测,有助于确定病原及其致病力。总的来说,蜡样芽孢杆菌对人畜的健康安全均构成了威胁,快速准确地检测能有效辅助治疗和提前预防,作者将主要检测方法进行了总结,希望能有助于全面准确地评估蜡样芽孢杆菌的风险,为主动监测和预警提供科学依据。 相似文献
4.
Enterotoxin production by strains of Staphylococcus aureus isolated from animals and main in Nigeria
Dosu Adekeye 《Veterinary microbiology》1980,5(2):143-150
Enterotoxin production by 194 strains of Straphylococcus aureaus isolated from animals and man was investigated. The organisms were also classified into biotypes, irrespective of sources. Human biotypes isolated from people had the highest proportion of enterotoxigenic strains (39%). The animal biotypes isolated from human beings were not enterotoxinenic, but 8.8% of the human biotypes isolated from animals yielded enterotoxin. About 18% of the animal biotypes isolated from animals were enterotoxigenic, while 25% of the untypable biotypes from all the sources investigated were enterotoxin producers. The predominant enterotoxins were A and B, with A accounting for 55%5% of the entrotoxins produced by human biotypes. Enterotoxins A, B and C were produced by some animal biotypes, and three canine biotypes produced enterotoxin combinations, BE, CE and ABE, respectively. From goat isolates, only four of the caprine biotypes were enterotoxigenic, including the only isolate producing enterotoxins B, C and E. The isolates obtained from horses and chickens were non-enterotoxigenic regardless of the biotypes. It is concluded that strains producing enterotoxins A and B may be responsible for outbreaks of staphylococcal food poisoning in Nigeria. The close association between man and his animals in this environment may account for the high prevalence (47%) of human biotypes in animals. 相似文献
5.
K Shinagawa K Ichikawa N Matsusaka S Sugii 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(3):469-474
A mouse lethal toxin (MLT) produced by Bacillus cereus isolated in vomiting-type food poisoning was purified by chromatography on DEAE-Sephadex A-25 followed by gel filtration on Sephadex G-75. Purified MLT possessed a molecular weight of 33,000-34,000. It showed mouse lethality and hemolytic (HL) activity on sheep and rabbit erythrocytes; the latter erythrocytes were more weakly hemolyzed than the former ones. However, fluid accumulation in mouse ligated intestinal loops was not induced by purified MLT at the highest concentration used. Both MLT and HL activities were stable at pH 6-9, during storage at -20 degrees C for 8 weeks, and resistant to papain, cholesterol, lecithin, and dithiothreitol treatments. Most activity was lost during storage at 4 degrees C or 25 degrees C for 2 weeks or upon treatment with trypsin, trypanblue, or ethanol. The activities were resistant to heating at 37 degrees C for 5 min, less resistant at 98 degrees C for 5 min, and sensitive at 60 degrees C for 5 min. It can be concluded from the results that MLT is different from the diarrheagenic toxin produced by B. cereus isolated in diarrheal-type food poisoning, but is similar to, if not identical, hemolysin II. 相似文献
6.
Achá SJ Kühn I Jonsson P Mbazima G Katouli M Möllby R 《Acta veterinaria Scandinavica》2004,45(1-2):27-36
The prevalence of diarrhoea in calves was investigated in 8 dairy farms in Mozambique at 4 occasions during 2 consecutive years. A total of 1241 calves up to 6 months of age were reared in the farms, and 63 (5%) of them had signs of diarrhoea. Two farms had an overall higher prevalence (13% and 21%) of diarrhoea. Faecal samples were collected from all diarrhoeal calves (n = 63) and from 330 healthy calves and analysed for Salmonella species, Campylobacter jejuni and enterotoxigenic Escherichia coli (ETEC). Salmonella spp. was isolated in only 2% of all calves. Campylobacter was isolated in 11% of all calves, irrespective of health condition, and was more frequent (25%) in one of the 2 diarrhoeal farms (p = 0.001). 80% of the isolates were identified as C. jejuni. No ETEC strains were detected among the 55 tested strains from diarrhoeal calves, but 22/55 (40%) strains from diarrhoeal calves and 14/88 (16%) strains from healthy calves carried the K99 adhesin (p = 0.001). 6,757 E. coli isolates were typed with a biochemical fingerprinting method (the PhenePlate) giving the same E. coli diversity in healthy and diarrhoeal calves. Thus it was concluded: i) the overall prevalence of diarrhoea was low, but 2 farms had a higher prevalence that could be due to an outbreak situation, ii) Salmonella did not seem to be associated with diarrhoea, iii) Campylobacter jejuni was common at one of the 2 diarrhoeal farms and iv) ETEC strains were not found, but K99 antigen was more prevalent in E. coli strains from diarrhoeal calves than from healthy, as well as more prevalent in one diarrhoeal farm. 相似文献
7.
During one year 1390 samples of pasteurized milk products from five different dairies were examined for content of B. cereus. The examination was done on the day of packaging and after incubation at 17 degrees C for 24 hrs. as well. On examination on the day of packaging 8.1 % were positive. No difference could be demonstrated between low-temperature pasteurized and high-temperature pasteurized products. However, differences were found from one plant to another (2.1 %--14.5 %). After incubation B. cereus were isolated from 17.2 % of low-temperature pasteurized samples and from 22.8 % of high-temperature pasteurized products. The occurrence of B. cereus varied according to season. In July-September the level of contamination was 40 %. It is concluded that during summer months bacteriological examination of dairy products should be supplemented with an examination for B. cereus. This could provide a valuable tool in checking the efficiency of dairy cleaning. 相似文献
8.
Nieminen T Rintaluoma N Andersson M Taimisto AM Ali-Vehmas T Seppälä A Priha O Salkinoja-Salonen M 《Veterinary microbiology》2007,124(3-4):329-339
To elucidate the occurrence of heat-stable toxin-producing strains among mastitic Bacillus isolates, 100 milk samples of mastitic cows from different parts of Finland were screened. Bacillus was identified as the major organism in 23 samples. Toxinogenic Bacillus isolates identified by sperm cell motility inhibition assay were isolated from six samples. Four isolates belonged to the species Bacillus pumilus and two to Bacillus licheniformis. The toxic substances were heat-stable and soluble to methanol thus being of non-protein nature. The methanol extracted substances disrupted the sperm cell plasma membrane permeability barrier at exposure concentrations of 1-15 microg ml(-1) (B. pumilus) or 20-30 microg ml(-1) (B. licheniformis). The toxic properties of the two mastitic B. licheniformis strains were similar to those of B. licheniformis strains known to produce the lipopeptide lichenysin A and the synthetase genes lchAA, lchAB and lchAC for lichenysin were found in the mastitic strains by PCR. Toxin synthetase genes for the syntheses of lichenysin or surfactin were searched but not found in the toxic B. pumilus strains. The ribopatterns of the mastitic B. pumilus and B. licheniformis isolates were similar to those of the toxinogenic strains described earlier from food poisoning incidents and contaminated indoor air. B. licheniformis and B. pumilus survive pasteurization and other heat treatments as spores. Toxin-producing strains of these species in the dairy production chain may thus be of food safety concern. 相似文献
9.
Cai Y Gao J Wang X Chai T Zhang X Duan H Jiang S Zucker BA Schlenker G 《DTW. Deutsche tier?rztliche Wochenschrift》2008,115(8):292-4, 296-7
Four hundred and twenty intestinal content samples (not including intestinal tissues) of freshwater fishes (60 silver carps, 100 carps, 100 crucian carps, 60 catfishes and 100 zaieuws) caught from one water reservoir were examined bacteriologically for the occurrence of C. perfringens. Isolates were examined by polymerase chain reaction (PCR) for genes encoding the four lethal toxins (alpha, beta, epsilon and iota) for classification into toxin types and for genes encoding enterotoxin and the novel beta2 toxin for further subclassification. C. perfringens could be isolated in 75 intestinal contents samples (17.9%) from freshwater fish including: 13 silver carps, 2 carps, 12 crucian carps, 40 zaieuws, and 8 catfishes. In 75 isolates, 58 strains (77.3%) were C. perfringens toxin type C (alpha and beta toxin positive), 13 strains (17.3%) were toxin type A (alpha toxin positive) and 4 strains (5.3%) were toxin type B (alpha, beta and epsilon toxin positive). In addition, the gene encoding for beta2 toxin was found in 47 strains (62.7%) of all the isolates, seven from type A, two from type B, and 38 from type C. The gene encoding for enterotoxin was not found in any isolate. These amplified toxin gene fragment were cloned and sequenced and compared with reference strains, the identity varied from 98.15% to 99.29%. This is the first report of C. perfringens alpha, beta, epsilon, beta2 toxins in freshwater fish and of beta, epsilon toxins in fish in general, and is the first discovery that the beta2 toxin could be detected in strains of type B. The origin of this bacterium and its importance to human food poisoning in freshwater fish is discussed. 相似文献
10.
Superphosphate poisoning is typically a disease of pregnant and lactating ewes under nutritional stress. Poisoning has been observed only in the late winter and spring. Most episodes occurred when hungry sheep were forced to graze short pastures top-dressed within one week prior to the onset of clinical signs. Fine weather which is favourable for the application of fertiliser also favours the occurrence of poisoning. Clinical signs include anorexia, thirst, diarrhoea, weakness and incoordination. Death usually occurs within 48 hours of the onset of clinical signs. In some outbreaks the presenting signs are those of hypocalcaemia but response to calcium therapy is transient. Poisoning results in a toxic tubular nephritis and uraemia. No satisfactory treatment can be suggested but poisoning can be prevented by avoiding exposure of sheep to top-dressed pastures. 相似文献
11.
O Sandvik 《Acta veterinaria Scandinavica》1973,14(1):176-183
Investigated strains of Bacillus thuringiensis were all good producers of casein precipitating proteinases (CP-enzymes).CP-enzymes produced by five strains of B. thuringiensis were serologically compared with enzymes produced by strains of B. cereus, B. licheniformis and B. subtilis. The technique used is a special enzymoserological procedure by which the proteolytic activity is neutralized by specific antisera. A close enzymoserological relationship was demonstrated between B. thuringiensis and B. cereus, while no interspecies cross-reactions occurred between enzymes of these species, and those of B. licheniformis and B. subtilis.The possibility of undetected transference of B. thuringiensis from bacteriologically treated plant material to animals is discussed in relation to the high degree of similarity between B. cereus and B. thuringiensis. 相似文献
12.
6株芽孢杆菌的生物学特性比较研究 总被引：4，自引：2，他引：2
以实验室分离保存的6株芽孢杆菌为材料,对其主要生物学特性进行了研究,包括产酶活力,对NaCl、牛胆盐、人工胃液和人工肠液的耐受性及对抗生素的敏感性。结果显示,枯草芽孢杆菌1、凝结芽孢杆菌和蜡样芽孢杆菌均能产生较高活性的中性蛋白酶和淀粉酶;2株枯草芽孢杆菌和凝结芽孢杆菌能耐较高浓度的NaCl;枯草芽孢杆菌2、凝结、纳豆和蜡样芽孢杆菌对牛胆盐的耐受性较强;除地衣芽孢杆菌外,其他5株芽孢杆菌对胃液和肠液的耐受性较好;6株芽孢杆菌均对常用饲用抗生素敏感。结果表明,枯草1、凝结、蜡样芽孢杆菌是优良的候选益生菌菌株。 相似文献
13.
Isolates of Pseudomonas aeruginosa from clinical infections in mink were subjected to serotyping and pulsed-field gel electrophoresis (PFGE) using SpeI. A total of 212 isolates of P. aeruginosa from the year 1998 to 2001 were included in this study: 168 isolates from mink obtained from 74 farm outbreaks of haemorrhagic pneumonia. Isolates from mink were separated into 34 distinct clones by PFGE subtyping. All isolates from mink infected during the same farm outbreak were identical, except in one case where two different strains were isolated from mink obtained from the same farm outbreak. P. aeruginosa of specific PFGE types were found to cause clusters of outbreaks on several farms within a few weeks of each other. However, PFGE types of strains causing clusters of farm outbreaks changed from year to year. These results suggest that some outbreaks of haemorrhagic pneumonia are caused by pathogenic strains of P. aeruginosa spread between farms and animals either mechanically, or through feed or water from a common source, rather than by random nosocomial infections with strains from the farm environment. 相似文献
14.
Superphosphate poisoning is typically a disease of pregnant and lactating ewes under nutritional stress. Poisoning has been observed only in the late winter and spring. Most episodes occurred when hungry sheep were forced to graze short pastures topdressed within one week prior to the onset of clinical signs. Fine weather which is favourable for the application of fertiliser also favours the occurrence of poisoning. Clinical signs include anorexia, thirst, diarrhoea, weakness and incoordination. Death usually occurs within 48 hours of the onset of clinical signs. In some outbreaks the presenting signs are those of hypocal- caemia but response to calcium therapy is transient. Poisoning results iu a toxic tubular nephritis and uraemia. No satisfactory treatment can be suggested but poisoning can be prevented by avoiding exposure of sheep to topdressed pastures. 相似文献
15.
Newcastle disease outbreaks in fowl in Great Britain during 1984 总被引：9，自引：0，他引：9
D J Alexander G W Wilson P H Russell S A Lister G Parsons 《The Veterinary record》1985,117(17):429-434
During February to July 1984, 23 outbreaks of Newcastle disease were confirmed in chickens in Great Britain. Use of available mouse monoclonal antibodies enabled unequivocal identification of the virus responsible for 22 of the outbreaks as similar to the avian paramyxovirus type 1 (A/PMV-1) virus causing neurotropic disease in pigeons during 1983 and 1984. Epidemiological investigations presented evidence that 19 of these outbreaks occurred either directly or indirectly as a result of spread from diseased pigeons infesting food stores at Liverpool docks. Virus was isolated from carcases of pigeons found among the food and samples of the food itself. The remaining outbreak was shown to involve a virus unrelated to the virus infecting pigeons. 相似文献
16.
A study of antigenic variants of foot-and-mouth disease virus by polyacrylamide gel electrophoresis of their structural polypeptides 总被引：1，自引：0，他引：1
Twenty-nine foot-and-mouth disease (FMD) type A virus strains, previously classified serologically as distinct subtypes were analysed by polyacrylamide gel electrophoresis (PAGE) to determine the extent of variation in the pattern of the structural polypeptides and to evaluate the technique as an aid to existing subtyping techniques. The majority of the subtypes examined had distinct polypeptide patterns, however, some variation also occurred between strains within a subtype. The position of VP2(1B) and VP3(1C) was often unchanged in different strains within a subtype and between geographically related subtypes over long periods of time. Changes in the position of VP1(1D) were also observed within a subtype. The technique was considered to be of value for the screening of isolates prior to conventional serological subtyping procedures and in the tracing of the possible origin of FMD outbreaks. 相似文献
17.
Kusiluka LJ Ojeniyi B Friis NF Kokotovic B Ahrens P 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2001,48(4):303-312
The genetic diversity of 60 field strains of Mycoplasma mycoides ssp. mycoides, small colony type (M. mycoides SC), comprising 56 isolates from cattle in Tanzania, one from Kenya, two from Botswana and one from Portugal, as well as the type (PG1T) and vaccine (T1-SR49) strains, was investigated. The strains were analyzed for variations in the EcoRI and Csp6I restriction sites in the genomic DNA using the amplified fragment length polymorphism (AFLP) technique, and variations in the BamHI restriction sites using pulsed-field gel electrophoresis (PFGE). Six AFLP types were detected among the analysed strains. The AFLP profiles of the type and vaccine strains were indistinguishable from each other. Indistinguishable AFLP profiles were found for 55 Tanzanian field strains, one of them isolated in 1990 and the other 54 isolated in 1998/1999, although one strain isolated in 1999 showed a different profile. Strains from different countries revealed different AFLP profiles. Six PFGE types were detected among the analysed strains, with all the 56 Tanzanian field strains displaying indistinguishable PFGE profiles. Strains from different countries revealed different PFGE profiles, and so did the type and vaccine strains. The strong genomic homogeneity among M. mycoides SC strains associated with outbreaks of contagious bovine pleuropneumonia in different regions of Tanzania suggests that the outbreaks of the disease in the 1990-99 period might have been caused by a single epidemic clone. Moreover, this study has demonstrated that AFLP and PFGE are potential tools for molecular epidemiological studies of M. mycoides SC infections. 相似文献
18.
Twelve Newcastle disease virus (NDV) strains were isolated from chickens involved in outbreaks of Newcastle disease (ND) in western China (Shaanxi, Gansu, Xinjiang, Qinghai and Guangxi provinces) between 1979 and 1999. All strains were determined to be velogenic by plaque formation, the mean death time (MDT) of embryonated eggs, and the intracerebral pathogenicity index (ICPI). For preparation of virus RNA, the acid guanidinium-thiocyanate method was used. A 908bp fragment of nucleotide was amplified by RT-PCR starting from the N terminal of the F gene and the PCR segments were cloned into the PGEM-T vector and sequenced. The similarities of the nucleotide sequences (1-519bp) and predicted amino acid sequences of the F gene (1-125) were analyzed by comparing the 12 NDV isolates with the NDV vaccine strains Lasota, B1, H1 and V4, with classical NDV strains and recent epizootic strains. Phylogenetic analysis demonstrated that all strains were of two novel genotypes; the NDV strains that caused the outbreak of ND in western China during 1998-1999 was of the genotype VIIa, whereas the strains from the Qinghai province (1979-1985) were of genotype VIII, which has been found predominately in southern Africa. 相似文献
19.
Purification and characterization of the vascular permeability factor produced by Bacillus cereus 总被引：6，自引：0，他引：6
K Shinagawa S Ueno H Konuma N Matsusaka S Sugii 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(2):281-286
Purification of an extracellular protein exhibiting the vascular permeability activity produced by Bacillus cereus was performed by ammonium sulfate precipitation followed by chromatography on DE-32 cellulose, Sephadex G-100, and Sephadex G-75. The purified protein was found to be electrophoretically and antigenically almost homogeneous although it contained a trace of contaminant. The molecular weight of the protein was calculated to be 45,000 by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The purified protein showed vascular permeability activity and mouse lethal toxicity, and caused fluid accumulation in ligated mouse intestinal loops, whereas it did not show any hemolytic and lecithinase activities. From these findings, the purified protein is suggested to be an enterotoxin (or a diarrheagenic toxin) responsible for diarrhea caused by B. cereus in a diarrheal-type food poisoning. 相似文献
20.
The pathogenicity of the metabolites of B. cereus was determined by bioassays with white mice, chick embryos, rabbits, and kittens. Cell-free filtrates of the cultures of several strains of B. cereus were used for application; in the mice the application was done i. v., i. p. and p. o., in the chick embryos via the allantoic sac, in the kittens p. o. and i. p., in the rabbits via tied-up sections of the small intestine by the loop-test method. It was revealed that some strains of B. cereus produced substances of exotoxin nature under suitable conditions. White mice and chick embryos were the best materials for their detection. 相似文献