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51.
AIM:To analyze the effects of outer membrane protein A (OmpA) from Acinetobacter baumannii ATCC 19606 on the autophagy of RAW264.7 cells. METHODS:The RAW264.7 cell model stimulated by OmpA was established. The effects of OmpA on the autophagy of RAW264.7 cells were detected by immunofluorescence, Western blot and transmission electron microscopy. RESULTS:The OmpA increased the expression of LC3B-Ⅱ and reduced the phosphorylation levels of Akt, mTOR and p70S6K. Rapamycin further reduced the phosphorylation levels of mTOR and p-70S6K, and increased the expression of LC3B-Ⅱ induced by OmpA. CONCLUSION:The OmpA of Acinetobacter baumannii induces autophagy via Akt/mTOR/p70S6K signaling pathway in the RAW264.7 cells. This work provides a basis for further research on the molecular mechanism of autophagy induced by Acinetobacter baumannii to find a new method against the infection of Acinetobacter baumannii.  相似文献   
52.
A total of 469 fecal samples were collected from American minks (Mustela vison) on a farm in Hebei Province in China and examined for Cryptosporidium by Sheather's sugar flotation technique and 8 Cryptosporidim isolates were obtained. The partial 18S rRNA, 70 kDa heat shock protein (HSP70), Cryptosporidium oocyst wall protein (COWP) and actin genes of six isolates were sequenced. Sequence data were analyzed together with known Cryptosporidium spp. and genotypes. Results of this multi-locus genetic characterization indicated that the six Cryptosporidium isolates in this study shared the same sequences of the genes studied and were different from known Cryptosporidium species and genotypes. The closest relative was Cryptosporidium ferret genotype with 7, 22, 2 and 2 nucleotide differences in the 18S rRNA, HSP70, COWP and actin genes, respectively. The homology to ferret genotype at the 18S rRNA locus was 99.1%, which is comparable to that between C. parvum and C. hominis (99.2%), or between C. muris and C. andersoni (99.4%). Therefore, the Cryptosporidium in minks in this study is considered a new genotype, the Cryptosporidium mink genotype.  相似文献   
53.
In mammals, insulin regulates S6K1, a key enzyme involved in the control of protein synthesis, via the well-documented phosphoinositide-3'kinase (PI3K) pathway. Conversely, S6K1 is activated by insulin in avian muscle despite the relative insulin insensitivity of the PI3K pathway in this tissue. Mitogen-activated protein kinase (MAPK) cascade is another insulin sensitive pathway. The aim of this study was to explore the potential involvement of the ERK1/2 MAPK pathway in the control of p70 S6 kinase (S6K1) in avian species. Firstly, we characterized ERK1/2 MAPK in various chicken tissues. ERK2 was the only isoform detected in avian species whatever the tissue studied. We also showed that ERK2 is activated in vivo by insulin in chicken muscle. The regulation and the role of ERK2 in insulin signaling were next investigated in chicken hepatoma cells (LMH) and primary myoblasts. Insulin stimulation led to ERK2 and S6K1 phosphorylation, and concomitantly increased kinase activity. U0126, an inhibitor of the ERK MAPK pathway, completely abolished insulin-induced S6K1 phosphorylation and activity in chicken myoblasts, whereas its effect was only partial in LMH cells. In conclusion, these results show that ERK1/2 MAPK is involved in the control of S6K1 by insulin in chicken cells, particularly myoblasts.  相似文献   
54.
几种农药对桑椹小粒性菌核病的防治效果试验   总被引:1,自引:0,他引:1  
桑椹菌核病是果用桑树的重要病害,为高效、安全控制该病对桑果生产的危害,进行了大田农药防治筛选试验。结果表明,70%甲基托布津可湿性粉剂500倍液、50%多菌灵-硫磺粉剂500倍液和1 000倍液对桑椹小粒性菌核病具有较好的防治效果,且对桑叶和桑椹无明显药害;70%甲基托布津粉剂1 000倍液、25%吡唑醚菌酯乳油1 500倍和3 000倍液以及40%嘧霉胺粉剂1 000倍液也有一定的防治效果。  相似文献   
55.
This study investigated the effect of dietary nutmeg oil (NO) on growth performance, blood parameters, lipid peroxidation and heat shock protein (HSP) 70 expression in Korean native chicken (KNC) reared under hot temperature. We allocated 273 meat‐type KNCs (Hanhyup3, 4‐week‐old, body weight [BW] = 539.93 ± 1.75 g) to the following three treatments with seven replicate pens (13 birds/pen) per treatment. Three treatment diets were as follows: (a) Control, basal diet without NO supplementation; (b) NO 250; and (c) NO 500, basal diet supplemented with 250 and 500 ppm NO respectively. Diets and water were provided ad libitum throughout the 6‐week feeding trial. During overall period (0–6 weeks), no differences (p > 0.05) were observed in BW gain (BWG), feed intake (FI) and feed conversion rate (FCR) among treatments. However, the FI at 0–3 weeks decreased (p < 0.05) quadratically with increasing NO levels. Most blood parameters did not differ (p > 0.05) among treatments, although the monocyte level of the NO 500 group was considerably lower (p > 0.05) than that of the other groups. Furthermore, dietary NO did not affect serum triglyceride, cholesterol, total protein, albumin, calcium, phosphorus and alanine aminotransferase (ALT) levels (p > 0.05); however, it linearly decreased serum aspartate aminotransferase (AST) level (p < 0.05). Additionally, serum malondialdehyde (MDA) concentration decreased (p < 0.05) and heart MDA concentration was lower (p = 0.08) with increasing dietary NO supplementation. After a 3‐hr heat (35°C) challenge, the rectal temperature (RT) reduced (p < 0.05) linearly with increasing NO levels. Dietary NO did not affect liver HSP70 (p > 0.05) gene expression. In conclusion, NO potentially enhanced the ability of chickens to alleviate heat stress. Furthermore, our findings suggest that lipid oxidation inhibition by dietary NO likely mediated the enhanced heat‐stress tolerance of the chickens.  相似文献   
56.
旨在研究急性热应激对山羊抗氧化能力、免疫功能和血淋巴细胞热休克蛋白70(HSP70)家族基因表达的影响。本试验选取5只健康、体况接近的(12±0.5)月龄波尔山羊×关中奶山羊杂交F1母羊,饲养于环控舱内(温度维持20℃,相对湿度60%),适应5d。第6天利用环控舱对5只试验羊进行38℃急性热应激处理12h,采集热应激前(0h,20℃)和热应激后2、4、8和12h试验羊血样。分别利用比色法测定血清抗氧化指标(总抗氧化能力、超氧化物歧化酶、谷胱甘肽过氧化物酶活性和丙二醛含量),ELISA法测定血清免疫指标(免疫球蛋白和细胞因子含量),实时荧光定量PCR法测定血淋巴细胞HSP70家族基因(HSPA1A、HSPA6和HSPA8)mRNA的表达量。结果显示:1)热应激时间对血清抗氧化指标有显著影响。与热应激前0h相比,血清T-AOC(P<0.05)、SOD(P<0.05)和GSH-Px(P<0.01)活性均在热应激8h后显著下降,MDA含量在热应激4h后显著增加(P<0.05)。2)热应激时间对血清免疫指标有显著影响。与热应激前0h相比,血清TNF-α、IL-1β、IFN-γ和IL-2含量分别在热应激4、8、8和4h后显著增加(P<0.05);IL-4(P<0.01)、IgG(P<0.01)、IgM(P<0.01)和IgA(P<0.05)含量分别在热应激12、4、4和4h后显著下降。3)热应激时间显著提高血淋巴细胞中HSP70家族基因(HSPA1A、HSPA6和HSPA8)的表达量。HSPA1AmRNA表达量呈先升高后下降的趋势,在热应激4h时达到峰值,各检测时间点均显著高于应激前水平(P<0.01);HSPA6mRNA表达量在热应激2h时显著升高(P<0.01),4h后恢复到应激前水平(P>0.05);HSPA8mRNA表达量在热应激4(P<0.05)、8(P<0.01)、12h(P<0.01)时显著高于应激前水平。在本试验条件下,38℃急性热应激能够抑制山羊的免疫和抗氧化功能;提高血淋巴细胞HSPA1A、HSPA6和HSPA8基因的表达量,其中HSPA1A对热应激温度和时间更敏感,可作为山羊热应激早期的分子标志物。  相似文献   
57.
奶牛热应激与HSP70的表达   总被引:4,自引:2,他引:2  
HSP70是应激条件下所诱导出的最为显著的热休克蛋白之一,是应激综合反应的代表。作者简要地介绍了HSP70的分类、结构、生理功能,及在热应激条件下奶牛HSP70的转录、翻译及检测方法。  相似文献   
58.
AIM:To explore the effects of Ku70 on the protein expression of human T-lymphotrophic virus 1 (HTLV-1) in HTLV-1 positive T cells. METHODS:The expression level of Ku70 in HTLV-1 positive T cells was exa-mined by Western blot. The siRNA targeting Ku70 was constructed and the effect of the siRNA on knockdown of Ku70 expression was determined by Western blot. After knockdown of Ku70 expression in the HTLV-1 positive T cells by siRNA, the expression of HTLV-1-related proteins at mRNA and protein levels was examined by real-time PCR and Western blot, and the expression levels of interferons and proinflammatory cytokines were examined by real-time PCR. RESULTS:The HTLV-1 positive T cells, including MT2, MT4 and C8199 cells, displayed a higher expression level of Ku70. The protein expression of HTLV-1 was increased in Ku70-silencing MT2 cells and MT4 cells. After knockdown of Ku70 expression in the MT2 cells and MT4 cells, the production of interferon (IFN)-α, IFN-γ and tumor necrosis factor-α was reduced.CONCLUSION:The HTLV-1 positive T cells have a higher expression level of Ku70. In HTLV-1 positive T cells, Ku70 promotes the production of interferons and proinflammatory cytokines and inhibits HTLV-1-related protein expression.  相似文献   
59.
The development of new octopus‐based products with a growing economic value ensures the commercial interest of this species, making live octopus export an activity of great interest. The aim of this study was to develop a method for long‐distance transportation of live octopus at high densities. The system was composed by 220‐L tanks with cooling and aeration, where the animals were kept separated from each others. The water temperature was maintained at 10°C, after a decreasing of 1°C/hr. Live octopus transportation was tested for 48 hr at two densities: 50 kg/m3 and 100 kg/m3. During this period, water parameters were monitored. Stress response was evaluated through the analysis of haemolymph, muscle and brain tissues. No mortality was registered after 48 hr for both treatments. In all trials, water quality remained within the normal limits in both densities; there was, however, a significative increase of ammonia levels in the water. Ammonia, dopamine and Hsp70 levels were analysed in the beginning and at the end of the experiment for both densities; however, no significant differences were found among them. In general, this system seems to be a viable solution for live octopus 48‐hr transportation at a density of 100 kg/m3.  相似文献   
60.
70%吡虫啉水分散粒剂(艾美乐)防治小麦穗蚜药效试验   总被引:3,自引:0,他引:3  
试验结果表明,70%吡虫啉水分散粒剂(艾美乐)在4~5g/667m^2的剂量下,对小麦穗蚜的防治效果优良,药后1~21d的防效均在91%以上,兼有持效性较长、对小麦安全、对环境友好及使用方便等优点,是防治小麦穗蚜的较好药剂.  相似文献   
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