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961.
AIM: To investigate the effects of xeroderma pigmentosum group D (XPD) gene on the proliferation of human umbilical arterial smooth muscle cells (HUASMCs) induced by oxidized low-density lipoprotein (Ox-LDL). METHODS: The recombinant plasmid pEGFP-N2/XPD was transfected into HUASMCs by liposome. The cells were divided into blank control group, pEGFP-N2 group, pEGFP-N2/XPD group, Ox-LDL group, Ox-LDL+pEGFP-N2 group and Ox-LDL+pEGFP-N2/XPD group. The proliferation rate of the cells was detected by MTT and EdU assays. The apoptotic rate and cell cycle distribution were analyzed by flow cytometry. The protein levels of XPD, caspase-3, Bcl-2 and Bax were determined by Western blot. RESULTS: Compared with blank control group, the expression of XPD was increased in pEGFP-N2/XPD group (P<0.05). According to the results of MTT and EdU assays, the cell proliferation in pEGFP-N2/XPD group was reduced compared with blank control group (P<0.05). Compared with Ox-LDL group, the cell proliferation in Ox-LDL+pEGFP-N2/XPD group was significantly inhibited (P<0.05). According to the results of flow cytometry, the cell proportion of S phase decreased and the G0/G1-phase cell proportion increased significantly in pEGFP-N2/XPD group and Ox-LDL+pEGFP-N2/XPD group compared with blank control group and Ox-LDL group, repectively (P<0.05). Compared with blank control group and Ox-LDL group, the protein level of Bcl-2 decreased and the protein levels of Bax and cleaved caspase-3 increased in pEGFP-N2/XPD group and Ox-LDL+pEGFP-N2/XPD group, respectively (P<0.05). CONCLUSION: XPD inhibits the proliferation of HUASMCs and promotes their apoptosis, and reduces the promoting effect of Ox-LDL on the proliferation of HUVSMCs. XPD may be the target for treatment of atherosclerosis.  相似文献   
962.
[Object] To setup the hyperspectral sensing models for estimating SPAD value of cotton leaves under waterlogging stress. [Method] Irrigation and drainage controllable plots were introduced to simulate the waterlogging stress treatment in the flowering and boll forming stage, during which the change characteristics of the cotton leaf spectral reflectance and SPAD value were observed after 1 d, 3 d, 6 d, 9 d waterlogging, respectively. To find out the hyperspectral sensing models for estimating SPAD value of cotton leaves under waterlogging stress, the correlation and regression relationships between SPAD value and spectrum parameters were analyzed. [Result] (1) The SPAD value of the fourth cotton leaf from the top was significantly lower than control when suffers from waterlogging for 3 d, when waterlogged 9 d the SPAD value decreased by around 15% compared with the control. (2) The cotton suffering from waterlogged damage in the flowering and boll forming stage caused the reflection peak in green light wave band became steep, while the near infrared spectral reflectance increased, and caused the reduction of red absorption and red edge position "blue shifts", the red edge position drifts towards short wave with 4~5 nm when suffers from waterlogging for 9 d. With increase of the waterlogged days, the red edge slope and red edge area increased with a maximum value at 6 d of waterlogging, meanwhile, the skewness and kurtosis of red edge increased. (3) After waterlogging, the SPAD value of the fourth cotton leaf from the top (chlorophyll content) had a remarkable correlation with red edge slope(Dr), red edge position(λr), green peak reflection(Rg), green peak position(λg), red well position(λo), blue edge area(SDb), yellow edge skewness(Sy), yellow edge kurtosis(Ky), red edge skewness(Sr), red edge kurtosis(Kr), etc. An experience linear, polynomial and exponential models for estimating SPAD value had been built through using the Sy, Sr, Kr as independent variables, respectively, their determination coefficient (R2) were greater than 0.9, and the root mean square error (RMSE) were less than 1; and an experience binary linear regression equation for estimating SPAD value had been built through multivariate regression using the λg, SDr/SDb(VI3), Sb, Sy, Ky as independent variables, the R2 was as high as 0.973, and the RMSE was 0.393. [Conclusion] The model can be remote sensing model used as estimating leaf SPAD of cotton value under waterlogging stress.  相似文献   
963.
AIM: To investigate the protective effect of lycopene on primary mouse cerebrocortical neurons exposed to tert-butyl hydroperoxide (t-BHP) and its mechanisms of in vitro.METHODS: Primary cerebrocortical neurons of newborn C57 mice were extracted and divided into normal group, t-BHP group, lycopene+t-BHP group and lycopene group. The neuronal damage was induced by t-BHP exposure for 24 h, and the cell viability was examined by MTT assay. ROS content was measured by flow cytometry, and the protein levels of Bax, Bcl-2, caspase-3, cleaved caspase-3 and cytochrome C were examined by Western blot.RESULTS: The primary mouse cortical neurons expressed MAP-2 protein. Lycopene at concentration of 4 μmol/L reversed the decrease in cell viability. Flow cytometry revealed that lycopene treatment attenuated ROS content under the condition of t-BHP exposure. In addition, the protein level of Bcl-2 was increased, and the expression of Bax, cleaved caspase-3 and cytochrome-C was suppressed in lycopene+t-BHP group.CONCLUSION: The protective effect of lycopene on cortical neurons with t-BHP-induced injury may be involved in the mechanism of neuronal antioxidative response by down-regulating caspase-3 and Bax/Bcl-2 through the mitochondrial apoptotic pathway.  相似文献   
964.
曹越  李大彪 《中国畜牧兽医》2021,48(8):2778-2786
乳脂肪是高质量的天然脂肪,其可为人类提供营养和能量,在各种膳食脂肪和油类中,是最容易被消化吸收的。乳脂肪是在乳腺中由从头合成或外源摄取的脂肪酸与甘油酯化形成的一种脂类物质,其含量的高低关系着牛奶品质的优劣和乳制品的加工特性。在奶牛的泌乳周期中,乳腺泌乳功能受多种因素影响,其中内分泌腺分泌的多种激素对奶牛乳腺上皮细胞(BMECs)乳脂的合成具有积极的调控作用。综上所述,作者介绍了氢化可的松、催乳素、胰岛素和生长激素4种泌乳相关激素对BMECs乳脂肪合成的调控机理,即从乳脂合成适宜的激素添加量、激素对乳脂球形态的影响方面初步阐释其调控作用,并从乳脂合成的关键酶及转录因子、激素对乳脂合成相关基因表达量方面深入阐释其作用机理,旨在为研究泌乳相关激素对奶牛乳腺内乳脂肪合成的调控机理提供参考。  相似文献   
965.
类器官(organoids)来源于自组织和自我更新的干细胞,是利用干细胞的自组织特性进行体外3D培养后形成的细胞团,与来源器官密切相关,再现了来源器官的三维细胞结构,并为探索来源器官的发病机制提供了新的模型。类器官系统是由自分泌、旁分泌或邻分泌信号调节下的细胞,或者外源性添加的细胞外基质(extracellular matrix,ECM)底物、小分子和生长因子等衍生而来,这些因素的相互作用创造了一个动态的环境,指导干细胞的自我更新和分化,以及细胞在类器官中的自我组装。诱导多能干细胞(induced pluripotent stem cells,iPSC)重编程方法结合3D类器官工具,使患者来源的类器官作为动物模型和人类临床试验之间的桥梁,是对细胞研究和在体试验的补充。在研究来源器官发育、生物学和病理生理学方面,类器官不仅是一种比传统细胞培养更具生理相关性的体外模型,而且还是再生医学和个性化医学领域中的新模型,有望成为研究营养素、药物、毒物及毒素等的作用机制及药物的筛选、再生医学等领域的重要模型。总之,类器官技术的发展增强了人们对器官和组织生理生化功能的认知。作者对肠、脑、肺脏、肝脏、子宫、卵巢等类器官培养和应用的研究进展进行综述,以期为类器官相关科研及应用提供参考。  相似文献   
966.
本试验旨在利用体外产气法评定西藏地区不同作物秸秆的营养价值。选取西藏地区5种常见作物秸秆(豌豆秸秆、玉米秸秆、青稞秸秆、小麦秸秆、油菜秸秆),通过单因素试验设计,利用体外产气法评定5种作物秸秆体外发酵48 h的产气量、理论最大产气量(Vf)、甲烷(CH4)产量、逻辑斯谛-指数(LE)模型产气参数、发酵液p H和氨态氮(NH3-N)浓度、主要挥发性脂肪酸(VFA)产量、体外干物质降解率(IVDMD)和体外中性洗涤纤维降解率(IVNDFD)等指标。结果显示:5种作物秸秆体外发酵48 h的产气量按玉米秸秆、青稞秸秆、豌豆秸秆、小麦秸秆、油菜秸秆的顺序依次降低。体外发酵48 h后,玉米秸秆的Vf、IVDMD、IVNDFD、CH4产量(豌豆秸秆除外)、丙酸和总VFA产量均显著高于其他4种作物秸秆(P0.05),其体外发酵液p H则显著低于其他秸秆(P0.05)。结果表明,玉米秸秆体外发酵效果最佳,与其他试验作物秸秆相比更容易被瘤胃微生物降解利用。  相似文献   
967.
AIM: To investigate the aggravating effect of albumin overload on the kidney injury induced by lipid nephrotoxicity, and to observe the renoprotective effect of simvastatin (SIMV) on adriamycin nephropathy (ADR) mice.METHODS: SPF healthy male BALB/c mice were randomly divided into control group, ADR group, ADR with bovine serum albumin (BSA) overload (ADR+BSA) group, and ADR with both BSA overload and SIMV treatment (ADR+BSA+SIMV) group. All mice were uninephrectomized under general anesthesia 2 weeks before setting up ADR model. ADR+BSA model started to be set up 4 weeks later. At the end of the 0th, 2nd, 6th, 10th and 14th weeks, 24 h urinary protein was evaluated. At the end of the 14th week, the serum biochemical indexes and the kidney pathological changes were observed, and glomerulosclerotic index (GSI) was also evaluated. The cholesterol in the kidney was measured by enzymic colorimetric method and oil red O staining. The expression of IL-1β, TGF-β1 and low-density lipoprotein receptor (LDLr) in the kidney tissues was determined by real-time PCR. The expression of IL-1β and IL-17 was measured by immunohistochemistry and the expression of IL-17 in the kidney was measured by ELISA.RESULTS: Compared with control group, the expression of IL-1β, TGF-β1, IL-17 and LDLr, and cholesterol content in the kidney and the GSI were all significantly increased in ADR group (P<0.05). Compared with ADR group, 24 h urinary protein, serum creatinine, the expression of IL-1β, IL-17 and LDLr, and cholesterol content in the kidney were all significantly increased in ADR+BSA group (P<0.05). Treatment with SIMV significantly decreased the expression of IL-1β, TGF-β1, IL-17 and LDLr. The accumulation of cholesterol in the kidney and the GSI were also decreased (all P<0.05).CONCLUSION: Inflammation aggravates the lipid deposition and glomerular sclerosis by increasing the expression of LDLr in ADR mice. Albumin overload further accelerates the progressive kidney damage by regulating the expression of IL-1β, TGF-β1 and IL-17, which promotes the increase in LDLr. The beneficial effect of SIMV might be mediated by its anti-inflammatory effect.  相似文献   
968.
以24个福建柏优树子代苗木为研究对象,对其生长量、生物量和根系等8个性状指标进行了方差分析、相关性分析和主成分分析。结果表明,1年生福建柏苗木各性状之间存在丰富的遗传变异,具有改良的潜力;各性状普遍受到了中等以上的遗传控制,其中总根体积的遗传力最高,达到了0.96;苗高仅与地径、地上鲜质量、总根长、总根体积存在显著或极显著相关,地径、地上干鲜质量、地下干鲜质量、总根长与总根体积相互之间存在极显著的相关;纬度是影响生物量性状的主要地理因子。对8个性状进行主成分分析后,得到能概括所测8个性状78.23%信息的3个主成分,计算出各家系的综合得分。  相似文献   
969.
冠春5号是以高代自交系327作母本,以自交系186作父本配制而成的苦瓜一代杂种。植株生长势旺盛,早熟,从播种至始收82 d(天)。主侧蔓均可结果,主蔓第1雌花节位为第7~8节。瓜长棒形,瓜长25~35 cm,横径5~7 cm,肉厚0.9~1.0 cm,单瓜质量420 g左右。果表皮浅绿色,点状突起与短条状突起相间瘤状物,尾部钝,果肉脆,苦味淡。早春栽培一般每667 m~2产量约3 000 kg,田间对白粉病和疫病的抗性优于对照新农村油绿苦瓜。适宜四川、重庆等地种植。  相似文献   
970.
为研究草莓中SCF复合体的功能,以栽培草莓品种‘74’为试材,采用同源克隆的方法分离出2个SKP1基因。这2个基因核苷酸序列全长均为519bp,核苷酸序列相似性为98.46%,氨基酸序列相似性为98.84%,并具有特殊的‘GVDED’尾巴结构,分别命名为FaSKP1-1a和FaSKP1-1b(基因登录号分别为KU975057和KU975058)。RT-PCR和dCAPS分析发现FaSKP1-1a和FaSKP1-1b在草莓根、茎、叶、花托、花粉、花柱、果实中均高表达,在花瓣中表达量低。上述结果表明FaSKP1-1可能在草莓SCF复合体的形成过程中发挥重要作用。  相似文献   
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