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991.
Neuritin is an extracellular glycophosphatidylinositol-linked protein that promotes neuronal survival, differentiation, function, and repair, but the exact mechanism of this neuroprotective effect remains unclear. Meanwhile, endoplasmic reticulum stress (ERS) induced apoptosis is attracting increased attention. In this work, we hypothesized that neuritin inhibited ERS to protect cortical neurons. To check this hypothesis, we exposed primary cultured cortical neurons to oxygen and glucose deprivation (OGD) for 45 min followed by reperfusion (R) to activate ERS. We then performed resuscitation for 6, 12, 24, and 48 h. ERS-related factors such as glucose-regulated protein 78 (GRP78), caspase-12 and CHOP were detected by Western blotting and quantitative real-time polymerase chain reaction assay. Apoptosis was assessed by Annexin V binding and propidium iodide staining. Ultrastructural changes of endoplasmic reticulum were observed under a transmission electron microscope. Results showed that GRP78 expression significantly increased at 12, 24, and 48 h and peaked at 24 h. Caspase-12 and CHOP expression significantly increased in a time-dependent manner at 12, 24, and 48 h. GRP78, caspase-12 and CHOP expression as well as apoptosis rate of primary cultured neurons and the ultrastructural changes of endoplasmic reticulum in the OGD/R?+?neuritin group significantly improved compared with the OGD/R group. In conclusion, the neuroprotection function of neuritin may be involved in ERS pathways.  相似文献   
992.
Cell size has implications for the package effect in photon absorption as well as for metabolic scaling of metabolism. In this study, we have avoided species-related differences by using isolates of the marine planktonic diatom Coscinodiscus granii with cells of different sizes and grown at different light intensities to investigate their energy allocation strategies. To make full use of incident light, several fold variations in cellular chlorophyll a content were employed across cell size. This modulation of pigment-related light absorbance was deemed effective as similar light absorbing capacities were found in all treatments. Unexpected low values of O2 evolution rate at the highest irradiance level of 450 μmol photons m?2 s?1 were found in medium and large cells, regardless of more photons being absorbed under these conditions, suggesting the operation of alternative electron flows acting as electron sinks. The growth rate was generally larger at higher irradiance levels except for the large cells, in which growth slowed at 450 μmol photons m?2 s?1, suggesting that larger cells achieved a balance between growth and photoprotection by sacrificing growth rate when exposed to high light. Although the ratio of carbon demand to rates of uncatalysed CO2 diffusion to the cell surface reached around 20 in large cells grown under higher irradiance, the carbon fixation rate was not lowered, due to the presence of a highly effective carbon dioxide concentrating mechanism.  相似文献   
993.
T cells have been successfully applied to cancer immunotherapy. However, a challenge is an expansion of T cells from cynomolgus monkey, which is a valuable non-human primate model for T cell therapy transferring to the clinic. Here, we compared several strategies to expand cynomolgus monkey T cell and developed an appropriate method. Our study demonstrated that 100 ng/ml CD3 mAb?+?1% PHA+ 1000 U/ml IL2 therapy significantly expanded peripheral blood CD3+ T cells without compromising T cell phenotype in vitro. The results of this study could be used for T cell remodeling, which has significant therapeutic potential in Chimeric Antigen Receptor-T (CAR-T) cell immunotherapy.  相似文献   
994.

Background

Crocetin, an agent derived from saffron, has multiple pharmacological properties, such as neuroprotective, anti-oxidant, and anti-inflammatory actions. These properties might benefit the treatment of Alzheimer’s disease (AD). In the present study, we tested whether crocetin attenuates inflammation and amyloid-β (Aβ) accumulation in APPsw transgenic mice, AD mouse models. Cell viability and the levels of Aβ40 and Aβ42 in HeLa cells stably transfected with Swedish mutant APP751 were evaluated. Mice with Swedish mutant APP751 transgene were used as transgenic mouse models of AD, and were orally administrated with crocetin. Aβ protein and inflammatory cytokines were measured with ELISA. NF-κB and P53 were measured with western blot assay. Learning and memory were analyzed with Morris water maze and novel object recognition tests.

Results

Crocetin significantly reduced Aβ40 and Aβ42 secretion in Hela cells without effecting cell viability. In AD transgenic mice, crocetin significantly reduced the pro-inflammatory cytokines and enhanced anti-inflammatory cytokine in plasma, suppressed NF-κB activation and P53 expression in the hippocampus, decreased Aβ in various brain areas, and improved learning and memory deficits.

Conclusion

Crocetin improves Aβ accumulation-induced learning and memory deficit in AD transgenic mice, probably due to its anti-inflammatory and anti-apoptotic functions.
  相似文献   
995.
新城疫病毒抗肿瘤研究进展   总被引:1,自引:0,他引:1  
新城疫病毒(Newcastle disease virus,NDV)为副黏病毒科,禽腮腺炎病毒属(Avulavirus)的禽副黏病毒Ⅰ型(APMV-Ⅰ),可对250多种禽类造成致死性感染,给世界范围内的家禽养殖造成了巨大损失。目前,研究发现NDV对人肿瘤细胞具有溶瘤作用,能够选择性地在癌细胞中复制。并且一些研究已经进行了人体临床试验,取得了良好的效果。因此,新城疫病毒是肿瘤治疗的潜在治疗剂。文中就NDV结构蛋白与毒力的关系、NDV直接溶瘤作用、NDV为载体的肿瘤基因治疗、NDV抗肿瘤与自噬等进行了综述。  相似文献   
996.
The F9 cell is a mouse embryonal teratocarcinoma which can be induced to differentiate into visceral endoderm by treatment with retinoic acid (RA). Treatment with RA in conventional studies was carried out in the constant presence of RA. Here we demonstrate that treatment with RA can be as short as 3 hrs to induce differentiation of F9 cells. Morphology, alpha-fetoprotein gene activity, and temporal patterns of F9 cell differentiation are the same with both short- and long-term treatment with RA.  相似文献   
997.
本文继先前工作后,进一步应用正常健康人外周血单个核细胞(PBMNC)经塑料培皿粘附技术把单核细胞分离出来,经培养进一步纯化,随后动态观察培养0,2,4,6和8天的单核-巨噬细胞的形态变化和对新鲜分离同种异基因个体PBMNC中NK活性的影响。实验表明,体外分化6天和8天的巨噬细胞质/核比例和胞浆内空泡显著增加,细胞直径约为0天时的2倍。这些细胞和PBMNC之比为0.5:1时,引起了NK细胞活性的50%以上抑制(4小时~(51)Cr标记K 562肿瘤的同位素释放试验)。这种抑制效应不为过氧化氢酶(Catalase 4000单位/毫升)和前列腺素合成酶的抑制剂(Indom 1×10~(-5)M)所阻断。实验证明,同种异基因个体的NK细胞不能识别巨噬细胞表面抗原,从而排除了巨噬细胞和K562肿瘤抗原竞争的可能性。实验还表明,巨噬细胞对NK活性的抑制是不受HLA约束的。应用高频超声振荡破碎巨噬细胞膜方法和免疫调变技术进一步提示,人体巨噬细胞对NK活性的抑制与巨噬细胞体积无关,而与体外分化所赋有的固有特性和它们分泌的免疫调节分子有关。  相似文献   
998.
葡萄胚珠,胚乳及胚的发育   总被引:2,自引:0,他引:2  
本文研究了“早玫瑰”和“新玫瑰”葡萄胚珠、胚乳和胚的发育。结果表明:花后3天胚珠即开始迅速生长,其生长的最终大小依品种成熟期的不同而各异。胚乳游离核在花后33天成为细胞状态。受精后16—21天,合子才开始第一次分裂。当胚乳充满珠心组织时,胚开始迅速发育并一直持续到果实成熟.胚的发育与果实的发育无明显竞争关系。  相似文献   
999.
黄淮海平原高产田作物群体结构特征   总被引:4,自引:5,他引:4  
本文利用实测资料分析了高产田作物群体结构特征。精播高产栽培麦田春季最大蘖数12×10~6/ha,群体最大叶面积指数5.5—6.0,成穗4.5—5.25×10~6/ha。传统高产栽培麦田春季最大蘖数15—18×10~6/ha,群体最大叶面积指数6.0—6.5,成穗6.0—7.5×10~6/ha。小麦营养生长与生殖生长期叶日积比,精播高产栽培麦田是1∶0.89,传统高产栽培麦田为1∶0.73。夏玉米种植密度主要受叶倾角的影响。紧凑型玉米品种的叶倾角大于65°,种植密度7.5—8.25×10~4/ha;平展型玉米品种的叶倾角小于50°,种植密度5.25—6.0×10~4/ha。  相似文献   
1000.
用呼吸道合胞病毒R6(武汉地方株)活毒滴鼻加用戍二醛固定的病毒感染的Hela细胞免疫BALB/C鼠,取脾细胞与小鼠骨髓瘤SP_2/0细胞融合,培育出分泌抗呼吸道合胞病毒单克隆抗体的杂交瘤细胞13株,这些细胞的染色体数为94至104条,其分泌的抗体分别属于鼠IgC_1、IgG_(2a)、IgG_(2b)亚类。腹水荧光抗体滴度为1:10000~1:100000。其中五株单抗有中和病毒作用,尤其是两株中和放价达1:128。应用免疫转印法证实了这些单抗分别能识别RSV6种主要结构蛋白,用7株识别不同病毒结构蛋白的单抗对12株合胞病毒进行抗原性分析,可将这些病毒区分为二个血清型,即A亚型和B亚型。  相似文献   
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