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921.
Fong-Yuan LIN Yeu-Yang TSENG Kun-Wei CHAN Shu-Ting KUO Cheng-Hsiung YANG Chi-Young WANG Masaki TAKASU Wei-Li HSU Min-Liang WONG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1055-1062
Orf virus (ORFV), a member of parapoxvirus, is an enveloped virus with genome
of double-stranded DNA. ORFV causes contagious pustular dermatitis or contagious ecthyma
in sheep and goats worldwide. In general, detection of viral DNA and observing ORFV virion
in tissues of afflicted animals are two methods commonly used for diagnosis of orf
infection; however, isolation of the ORFV in cell culture using virus-containing tissue as
inoculum is known to be difficult. In this work, the ORFV (Hoping strain) isolated in
central Taiwan was successfully grown in cell culture. We further examined the biochemical
characteristic of our isolate, including viral genotyping, viral mRNA and protein
expression. By electron microscopy, one unique form of viral particle from ORFV infected
cellular lysate was demonstrated in the negative-stained field. Moreover, immunomodulating
and anti-influenza virus properties of this ORFV were investigated. ORFV stimulated human
monocytes (THP-1) secreting proinflammatory cytokines IL-8 and TNF-α. And, pre-treatment
of ORFV-infected cell medium prevents A549 cells from subsequent type A influenza virus
(IAV) infection. Similarly, mice infected with ORFV via both intramuscular and
subcutaneous routes at two days prior to IAV infection significantly decreased the
replication of IAV. In summary, the results of a current study indicated our Hoping strain
harbors the immune modulator property; with such a bio-adjuvanticity, we further proved
that pre-exposure of ORFV protects animals from subsequent IAV infection. 相似文献
922.
923.
924.
Nicole I. Stacy Mary B. Nabity Nicole Hackendahl Melanie Buote Jennifer Ward Pamela E. Ginn William Vernau William L. Clapp John W. Harvey 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(1):113-120
Abstract: Two young adult dogs with gastrointestinal signs were each found to have an intra‐abdominal mass based on physical examination and diagnostic imaging. On exploratory laparotomy, small intestinal masses and mesenteric lymphadenopathy were found in both dogs; a liver mass was also found in dog 1. Cytologic and histologic examination of intestinal and liver masses and mesenteric lymph nodes revealed 2 distinct lymphoid cell populations: lymphoblasts and atypical Mott cells. With Romanowsky stains, the atypical Mott cells contained many discrete, clear to pale blue cytoplasmic inclusions consistent with Russell bodies that were positive by immunohistochemistry for IgM and CD79a in both dogs and for IgG in dog 2. The Mott cells and occasional lymphoblasts stained strongly positive with periodic acid‐Schiff. Using flow cytometric immunophenotyping in dog 1, 60% of peripheral blood mononuclear cells and 85% of cells in an affected lymph node were positive for CD21, CD79a, IgM, and MCH II, indicative of B‐cells. With electron microscopy, disorganized and dilated endoplasmic reticulum was seen in Mott cells in tumors from both dogs. Antigen receptor gene rearrangement analysis of lymph node and intestinal masses indicated a clonal B‐cell population. Based on cell morphology, tissue involvement, and evidence for clonal B‐cell proliferation, we diagnosed neoplasms involving Mott cells. To the authors' knowledge, this is the second report of Mott cell tumors or, more appropriately, B‐cell lymphoma with Mott cell differentiation, in dogs. More complete characterization of this neoplasm requires further investigation of additional cases. This lymphoproliferative disease should be considered as a differential diagnosis for canine gastrointestinal tumors. 相似文献
925.
The prognosis of liver cancer was inferior among tumors. New medicine treatments are urgently needed. In this study, a novel exopolysaccharide EPS364 was purified from Vibrio alginolyticus 364, which was isolated from a deep-sea cold seep of the South China Sea. Further research showed that EPS364 consisted of mannose, glucosamine, gluconic acid, galactosamine and arabinose with a molar ratio of 5:9:3.4:0.5:0.8. The relative molecular weight of EPS364 was 14.8 kDa. Our results further revealed that EPS364 was a β-linked and phosphorylated polysaccharide. Notably, EPS364 exhibited a significant antitumor activity, with inducing apoptosis, dissipation of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS) in Huh7.5 liver cancer cells. Proteomic and quantitative real-time PCR analyses indicated that EPS364 inhibited cancer cell growth and adhesion via targeting the FGF19-FGFR4 signaling pathway. These findings suggest that EPS364 is a promising antitumor agent for pharmacotherapy. 相似文献
926.
927.
毒害艾美耳球虫初次感染雏鸡免疫器官IL-2和淋巴细胞增殖功能变化 总被引:1,自引:0,他引:1
应用组织匀浆涂片和酸性α-醋酸萘酯酶(ANAE)染色及细胞培养技术和四甲基偶氮唑盐(MTT)测定法对毒害艾美耳球虫(eimeria necatrix,E.necatrix)初次感染雏鸡免疫器官的T细胞比例、白细胞介素-2(interleukin-2,IL-2)诱生活性、T细胞和B细胞对ConA或PMA的增殖功能的动态变化进行了较全面系统的研究。结果发现,E.necatrix初次感染雏鸡,其胸腺和脾脏T细胞比例分别于感染后7~21d和7~24d明显高于对照雏鸡;IL-2诱生活性分别于感染后16~18d和18~21d较对照雏鸡显著升高;T细胞对ConA的增殖反应分别在感染后14~16d和10~18d明显增加。法氏囊和脾脏B细胞对PMA的增殖反应分别于感染后14~24d和14~21d显著高于对照雏鸡。表明E.necatrix初次感染雏鸡免疫器官的IL-2调节及细胞免疫和体液免疫功能均明显提高。 相似文献
928.
阿维菌素对小鼠雌性生殖细胞的致突变性研究 总被引:1,自引:0,他引:1
阿维菌素是我国生产的一种高效广谱抗寄生虫抗生素,对动物的消化道线虫和外寄生虫有很强的驱杀作用。本文选择了第二次减数分裂中期相(MII)卵母细胞和第一次分裂中期相合子染色体畸变分析方法,研究其对哺乳动物雌性生殖细胞的遗传毒性。1.MII卵母细胞染色体畸变分析:根据阿维菌素的小鼠急性毒性试验结果(小鼠经口LD50=19.19mg/kg),设以下剂量组:1.92、3.84和9.60mg/kg(约相当于1 相似文献
929.
So Young Kim Myoung-Sook Shin Geum Jin Kim Hyukbean Kwon Myong Jin Lee Ah-Reum Han Joo-Won Nam Chan-Hun Jung Ki Sung Kang Hyukjae Choi 《Marine drugs》2021,19(8)
The epithelial–mesenchymal transition (EMT) of cancer cells is a crucial process in cancer cell metastasis. An Aquimarina sp. MC085 extract was found to inhibit A549 human lung cancer cell invasion, and caprolactin C (1), a new natural product, α-amino-ε-caprolactam linked to 3-methyl butanoic acid, was purified through bioactivity-guided isolation of the extract. Furthermore, its enantiomeric compound, ent-caprolactin C (2), was synthesized. Both 1 and 2 inhibited the invasion and γ-irradiation-induced migration of A549 cells. In transforming growth factor-β (TGF-β)-treated A549 cells, 2 inhibited the phosphorylation of Smad2/3 and suppressed the EMT cell marker proteins (N-cadherin, β-catenin, and vimentin), as well as the related messenger ribonucleic acid expression (N-cadherin, matrix metalloproteinase-9, Snail, and vimentin), while compound 1 did not suppress Smad2/3 phosphorylation and the expression of EMT cell markers. Therefore, compound 2 could be a potential candidate for antimetastatic agent development, because it suppresses TGF-β-induced EMT. 相似文献
930.
水稻对稻瘟病抗性的分子生物学研究进展 总被引:17,自引:0,他引:17
介绍了水稻对稻瘟病抗性的分子生物学研究进展,主要包括:用于定位作图的分子标记的种类和特点、稻瘟病抗性基因的分子标记定位、稻瘟病抗性基因的等位性比较研究、稻瘟病菌生理小种无毒基因的克隆以及稻瘟病抗性基因克隆研究进展等。 相似文献