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61.
AIM: To investigate the expression and roles of family with sequence similarity 3, member C (FAM3C) in oral squamous-cell carcinoma cells. METHODS: The mRNA and protein expression levels of FAM3C in dysplastic oral keratinocyte (DOK) and oral squamous-cell carcinoma WSU-HN6 cells were detected by RT-qPCR and Western blot. The WSU-HN6 cells were treated with siFAM3C or FAM3C antibody. After 24, 48 and 72 h, the viability of WSU-HN6 cells was measured by CCK-8 assay, and the activation of protein kinase B (Akt) was detected by Western blot. Adenovirus was used to mediate over-expression of FAM3C in the DOK cells. The DOK cell viability was measured by CCK-8 assay after adenovirus infection for 24, 48 and 72 h, and the activation of Akt was detected by Western blot. RESULTS: Compared with the DOK cells, the mRNA and protein levels of FAM3C were significantly increased in the WSU-HN6 cells (P<0.05). The viability of WSU-HN6 cells transfected with siFAM3C was significantly inhibited at 48 h and 72 h (P<0.05). siFAM3C treatment inhibited the activation of Akt (P<0.05). FAM3C antibody treatment also suppressed the viability of the WSU-HN6 cells at 48 h and 72 h and the activation of Akt (P<0.05). Over-expression of FAM3C in the DOK cells promoted the cell viability at 48 h and 72 h and activated Akt (P<0.05). CONCLUSION: FAM3C might promote oral squamous-cell carcinoma cell growth by activating Akt.  相似文献   
62.
An 8‐wk feeding trial was conducted to evaluate the effects of varying dietary protein and lipid levels with different protein‐to‐energy (P/E) ratios on growth, feed utilization, and plasma biochemical parameters of Sinocyclocheilus graham. Nine experimental diets were formulated to contain three protein levels (35, 40, and 45%), and each with three lipid levels (4, 8, and 12%), to produce a range of P/E ratios from 71.31 to 98.64 mg protein/kcal. Each diet was randomly assigned to triplicate groups of 25 fish. Fish grew best when fed the diet containing 45% protein and 12% lipid. However, fish fed the diet with 40% protein and 8% lipid had similar weight gain and specific growth rate as those fed the above diet but showed relatively better feed conversion ratio, protein efficiency ratio, and protein and energy retentions. Additionally, plasma total amino acids and blood urea nitrogen contents and γ‐glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase activities in fish fed the diet containing 40% protein and 8% lipid were relatively low among the dietary treatments. These results may indicate that a diet containing 40% protein and 8% lipid with P/E ratio of 84.05 mg protein/kcal would be suitable for the optimal growth, feed utilization, and health of S. graham.  相似文献   
63.
CAO Rui-ping  WANG Jiao  WANG Ce 《园艺学报》2018,34(6):1061-1066
AIM: To investigate the role of zerumbone (ZER) in 1-methyl-4-phenylpyridinium (MPP+)-induced cytotoxicity of human neuroblastoma SH-SY5Y cells. METHODS: Human neuroblastoma SH-SY5Y cells were cultured in vitro and the protective effect of ZER against MPP+-induced cytotoxicity was measured by CCK-8 assay. Flow cytometry was used to determine the apoptosis and reactive oxygen species (ROS). The expression of Parkinson disease protein 7 (PARK7) was knocked-down by using PARK7-specific short hairpin RNA (shRNA). The protein levels of PARK7, nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were determined by Western blot. RESULTS: MMP+ remarkably reduced the cell viability in a dose-dependent and time-dependent manner. The SH-SY5Y cell injury model was established by treatment with MPP+ at 600 μmol/L for 24 h. ZER up-regulated the protein levels of PARK7 and Nrf2 (P<0.05), alleviated apoptosis (P<0.05), and reduced ROS production (P<0.05) in the SH-SY5Y cell injury model. Meanwhile, N-acetyl-L-cysteine (NAC) had the similar functions. Moreover, significant reductions in the protein levels of Nrf2 and HO-1 (P<0.05), and obvious increases in apoptosis (P<0.05) and ROS level (P<0.05) were demonstrated in PARK7-knockdown cells. CONCLUSION: ZER protects SH-SY5Y cells against MPP+-induced cytotoxi-city, which may be related to activation of PARK7/Nrf2/HO-1 pathway, and subsequent attenuation of oxidative stress and apoptosis.  相似文献   
64.
昆虫嗅觉相关蛋白的研究进展   总被引:2,自引:0,他引:2  
昆虫对自然环境中复杂化学信号的识别多依赖于其灵敏的嗅觉系统,选择寄主、觅食、寻找配偶等行为的发生都以嗅觉识别为基础,而完成嗅觉识别还需要多种嗅觉相关蛋白的参与。嗅觉相关蛋白主要包括6种,即气味结合蛋白、化学感受蛋白、气味受体、感觉神经元膜蛋白、离子型受体和气味降解酶。不同种类和性别的昆虫中,嗅觉蛋白的种类、数量和分布各不相同。由于嗅觉蛋白在昆虫识别外界气味分子中的重要作用,国内外近年来对其展开了广泛、深入的研究。本文从几种嗅觉相关蛋白的生化特性、分子结构、生理功能、分布表达部位和研究概况等角度,较详细地综述了近年来国内外昆虫嗅觉相关蛋白的研究进展。  相似文献   
65.
This study compares the effect of food type (formulated diet vs. natural food) and fish size on protein and energy utilization efficiencies for growth in common sole, Solea solea (L.). Replicate groups of common sole (mean initial body weight ± SD was 45.7 g ± 2.1 and 111.2 g ± 4.2) received the diets at five (natural feed) or four (formulated diet) feeding levels. The protein utilization efficiency for growth (kgCP) was higher (> 0.001) in common sole fed ragworms than in common sole fed the formulated diet (respectively, 0.40 and 0.31). Likewise, the energy utilization efficiency for growth (kgGE) was higher (= 0.001) in common sole fed ragworms than in common sole fed the formulated diet (respectively, 0.57 and 0.33). The protein maintenance requirement was not different between food types (= 0.64) or fish size (= 0.41) being on average 0.82 g kg?0.8 day?1. The energy maintenance requirement was not different between food type (= 0.390) but differed between fish size (= 0.036). The gross energy maintenance requirement of small common sole was 35 kJ g?0.8 day?1. The gross energy maintenance requirement of large common sole was 25 kJ g?0.8 day?1. In conclusion, the low growth of common sole fed formulated diets was related to reduced feed utilization.  相似文献   
66.
对长江口雌性和雄性成体凤鲚(Coilia mystus)整体的营养成分和品质进行了分析与评价。结果显示,雌、雄凤鲚整体水分、粗蛋白、粗脂肪和灰分的质量分数分别为78.36%±1.41%、76.70%±1.20%,14.25%±1.05%、15.18%±0.12%,4.61%±1.78%、4.84%±0.27%和2.22%±0.38%、2.97%±0.64%,雌、雄间均不具有显著性差异(P0.05)。雌、雄均含有18种组成蛋白质的氨基酸,总量分别为66.20%±5.78%和65.93%±6.35%(质量分数,干样),其中8种必需氨基酸(EAA)总量分别是25.07%±1.93%和23.95%±2.21%,两者间不具有显著性差异(P0.05),分别占氨基酸总量的37.90%和36.33%,雌、雄凤鲚的必需氨基酸组成比例均符合FAO/WHO的标准。色氨酸是雌、雄凤鲚整体的第一限制性氨基酸,蛋氨酸+胱氨酸是第二限制性氨基酸,雌、雄凤鲚整体的EAAI分别为70.73和66.99,4种鲜味氨基酸总量分别为25.99%±2.53%和26.02%±2.3%(质量分数,干样)。雌性凤鲚的饱和脂肪酸(SFA)含量显著低于雄性(P0.05),而多不饱和脂肪酸(PUFA)含量则显著高于雄性(P0.05),单不饱和脂肪酸(MUFA)两者无显著差异(P0.05)。雌性凤鲚脂肪酸中EPA与DHA质量分数分别为5.70%±0.24%和10.15%±1.31%,显著高于雄性凤鲚的1.05%±0.40%和1.06%±0.44%。结果表明,长江口雌、雄成体凤鲚整体的氨基酸较均衡,而雌性凤鲚的脂肪酸营养更为丰富,比雄性凤鲚具有更好的食用价值与保健作用。  相似文献   
67.
The objective of this study was to evaluate the effects of defoliation frequency (either at two‐ or three‐leaf stage) and nitrogen (N) application rate (0, 75, 150, 300, 450 kg N ha?1 year?1) on herbage carbohydrate and crude protein (CP) fractions, and the water‐soluble carbohydrate‐to‐protein ratio (WSC:CP) in perennial ryegrass swards. Crude protein fractions were analysed according to the Cornell carbohydrate and protein system. Carbohydrate fractions were analysed by ultra‐high‐performance liquid chromatography. Sward defoliation at two‐leaf stage increased the total CP, reduced the buffer‐soluble CP fractions and decreased carbohydrate fractions of herbage (P < 0·001). The effect of defoliation frequency was less marked during early spring and autumn (P < 0·001) than for the rest of the seasons. An increase in N application rate was negatively associated with WSC, fructans and neutral detergent fibre (P < 0·001), and positively associated with CP and nitrate (N‐NO3) contents of herbage. Nitrogen application rate did not affect CP fractions of herbage (P > 0·05). The fluctuations in CP and WSC contents of herbage resulted in lower WSC:CP ratios during early spring and autumn (0·45:1 and 0·75:1 respectively) than in late spring (1·11:1). The herbage WSC:CP ratio was greater (P < 0·001) at the three‐leaf than the two‐leaf defoliation stage and declined as the N application increased in all seasons (P < 0·001). The results of this study indicate that CP and carbohydrate fractions of herbage can be manipulated by sward defoliation frequency and N application rate. The magnitude of these effects, however, may vary with the season.  相似文献   
68.
为建立并优化草鱼鳃蛋白质组双向电泳的技术体系,实验将草鱼鳃经裂解处理后,通过固相p H梯度胶条进行一向等电聚焦和SDS聚丙烯酰胺凝胶垂直电泳进行蛋白分离,对不同的裂解液配方、蛋白纯化方法、IPG胶条的分离范围、上样量和染色方法等进行了探索和优化,并应用lmage Master 2D Platinum 7.0软件对电泳图谱进行了分析。结果表明:采用裂解液中添加DTT来取代Tris和TBP、选择分离范围为pH4-7的IPG胶条和150μg的主动水化上样,电泳结束后对凝胶进行硝酸银染色,获得了覆盖范围广、低背景、高分辨率、适合差异蛋白分析的双向电泳参考图谱。  相似文献   
69.
深水网箱和池塘养殖凡纳滨对虾肌肉营养成分的比较分析   总被引:2,自引:0,他引:2  
对深水网箱和池塘养殖凡纳滨对虾(Litopenaeus vannamei)肌肉常规营养成分、氨基酸和脂肪酸质量分数进行了比较分析。结果显示:1)网箱养殖对虾肌肉粗蛋白质量分数显著高于池塘养殖(P0.05),而水分、粗脂肪和粗灰分质量分数无显著差异(P0.05);2)肌肉中检测到18种常见氨基酸,网箱养殖对虾肌肉氨基酸总量(TAA)、天门冬氨酸(Asp)、异亮氨酸(Ile)、精氨酸(Arg)和脯氨酸(Pro)质量分数显著高于池塘养殖(P0.05),而必需氨基酸(EAA)、半必需氨基酸(HEAA)、鲜味氨基酸(DAA)和虾味氨基酸(PFAA)两者无显著差异(P0.05);3)肌肉中检测到30种常见脂肪酸,两者的饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)、多不饱和脂肪酸(PUFA)、n-3多不饱和脂肪酸(EPA和DHA)质量分数差异显著(P0.05),以网箱养殖对虾较高;两者的棕榈酸(C16∶0)质量分数最高,且网箱养殖对虾EPA+DHA质量分数是池塘养殖的1.90倍。结果表明,网箱养殖对虾营养成分要优于池塘养殖,具有较高的营养价值。  相似文献   
70.
To investigate the nutritional value of the marine micro‐alga Isochrysis galbana Tahitian Isochrysis strain (T.iso) as an alternative feed for aquaculture during culture age, its biochemical composition was studied under autotrophic and controlled culture conditions at different growth stages: exponential phase, early and late stationary phases and decay phase. Analysis showed that C14:0, C16:0, C16:1, C18:4 (n‐3) and C22:6 (n‐3) were the most abundant fatty acids in this alga at different growth stages. The highest values of monounsaturated fatty acids were recorded at the late stationary and the decay phases. However, the highest levels of polyunsaturated fatty acids were observed at the early stationary phase. At all growth stages, I. galbana (T.iso) contained arabinose, xylose, mannose, galactose and glucose. Glucose represented the main sugar, and its content per dry alga biomass weight increased with increasing age of the culture and reached about fourfold in the decay phase. The maximum protein content was also observed during this last phase.  相似文献   
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