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Caitlin M. Cossaboom Laura Córdoba Dianjun Cao Yan-Yan Ni Xiang-Jin Meng 《Journal of virology》2012,86(23):13124-13125
Hepatitis E virus (HEV) is a single-strand positive-sense RNA virus in the family Hepeviridae. The disease caused by HEV, hepatitis E, is an important public health problem in developing countries of Asia and Africa and is also endemic in many industrialized countries, including the United States. HEV has been identified from several other animal species in addition to humans, including the pig, chicken, mongoose, deer, rabbit, ferret, bat, and fish. Here we report the complete genome sequence of the first strain of HEV from rabbits in the United States. Sequence and phylogenetic analyses revealed that the U.S. rabbit HEV is a distant member of the zoonotic genotype 3 HEV, thus raising a concern for potential zoonotic human infection. A unique 90-nucleotide insertion within the X domain of the ORF1 was identified in the rabbit HEV, and this insertion may play a role in the species tropism of HEV. 相似文献
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Jun‐juan Wang Qi‐min Zhang Wei‐wei Ni Xin Zhang Ying Li Ai‐li Li Peng Du Chun Li Su‐su Yu 《Microbiology and immunology》2019,63(8):303-315
We investigated the correlation between the beneficial effect of Lactobacillus acidophilus on gut microbiota composition, metabolic activities, and reducing cow's milk protein allergy. Mice sensitized with β‐lactoglobulin (β‐Lg) were treated with different doses of L. acidophilus KLDS 1.0738 for 4 weeks, starting 1 week before allergen induction. The results showed that intake of L. acidophilus significantly suppressed the hypersensitivity responses, together with increased fecal microbiota diversity and short‐chain fatty acids (SCFAs) concentration (including propionate, butyrate, isobutyrate, and isovalerate) when compared with the allergic group. Moreover, treatment with L. acidophilus induced the expression of SCFAs receptors, G‐protein–coupled receptors 41 (GPR41) and 43 (GPR43), in the spleen and colon of the allergic mice. Further analysis revealed that the GPR41 and GPR43 messenger RNA expression both positively correlated with the serum concentrations of transforming growth factor‐β and IFN‐γ (p < .05), but negatively with the serum concentrations of IL‐17, IL‐4, and IL‐6 in the L. acidophilus–treated group compared with the allergic group (p < .05). These results suggested that L. acidophilus protected against the development of allergic inflammation by improving the intestinal flora, as well as upregulating SCFAs and their receptors GPR41/43. 相似文献
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A Pop A Opri?an A Pop A Cerbu M Stavarache R Ni?u 《Archives roumaines de pathologie expérimentales et de microbiologie》1989,48(4):373-378
The frequency of Toxoplasma gondii infection in the meat provided by two abattoirs, as well as the pathogenicity of the isolated strains were studied. The parasite carriage was investigated on 299 pools of diaphragmatic muscle (1 pool = 10 animals) from 740 swine, 910 cattle and 1340 sheep: the methods used were bioassays on mice and the precocious identification of the tachyzoites in the peritoneal exudate and after 30 days the cerebral cysts. There were obtained 27 positive results (9.01%), in the examined pools of meat, without significant differences as concerns the frequency in relation to the animal species. Out of these strains two were virulent for mice and rabbits. 相似文献
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Mutations in the human P gene result in oculocutaneous albinism type 2, the most common form of albinism. Mouse melan‐p1 melanocytes, cultured from mice null at the homologous pink‐eyed dilution (p) locus, exhibit defective melanin production. A variety of compounds including tyrosine, NH4Cl, bafilomycin A1, concanamycin, monensin, and nigericin are capable of restoring melanin synthesis in these cells. In the current study, we investigated the subcellular effects of bafilomycin A1 and monensin treatment of melan‐p1 cells. Both agents play two roles in the processing of tyrosinase (Tyr) in melan‐p1 cells. First, combined glycosidase digestion and immunoblotting analysis showed that these agents reduce levels of Tyr retained in the endoplasmic reticulum (ER) and facilitate the release of Tyr from the ER to the Golgi. Secondly, treatment with these compounds resulted in the stabilization of Tyr. Surprisingly, induction of melanin synthesis corresponds more closely with diminution of ER‐retained Tyr, rather than the absolute amount of Tyr. Our results suggest that bafilomycin A1 and monensin induce melanin synthesis in melan‐p1 cells mainly by facilitating Tyr processing from the ER to the Golgi by increasing the pH in either the ER or the ER–Golgi intermediate compartment. 相似文献
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Three zones of esterase activity were established in zymograms of erythrocyte lysates in karakul sheep by means of starch gel electrophoresis. These zones were distinguished according to their substrate specificity and inhibition tests and desnguated as arylesterase (I), carbonic anhydrase (II) and aliesterase (III). The following phenotypes of erythrocyte arylesterase were distinguished in the two populations of karakul sheep studied: AEs - A, AEs - AB, AEs - AC, AEs - AD, AEs - B, AEs - BC, AEs - BD, AEs - C, AEs - CD, AEs - D. These phenotypes are controlled by 4 dominant alleles, VIZ. AEsA, AEsB, AEsC, AEsD. Gene frequencies vary from population to population: from 0.012 +/- 0.005 to 0.118 +/- 0.027, from 0.331 +/- 0.021 to 0.340 +/- 0.012, from 0.601 +/- 0.022 to 0.250 +/- 0.011 and from 0.056 +/- 0.003 to 0.292 +/- 0.011 for AEsA, AEsB, AEsC and AEsD respectively. The actually observed distribution of arylesterase phenotypes is in accordance with the theoretically expected values (p is less than 0.95). 相似文献
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Wenjun Geng Jinggong Xiangyu Xiuzhen Li Zhongning Zhang Deyuan Han Yongwei Li 《Insect Science》1997,4(4):364-368
Abstract Field trials by sex pheromone of aphid to trap peach aphids Myzus persicae have been carried out in 1995 and in 1996. Suitable time and the effect of ratio of two components nepetalactone and nepetalactol to apply the lure have been observed. 相似文献