细胞外Ba2+对大鼠心肌细胞L型钙通道的影响

目的：观察细胞外Ba²⁺对记录大鼠心肌细胞L型钙通道的影响。方法：采用急性酶解分离法获得大鼠的单个心肌细胞,使用全细胞膜片钳技术记录L型钙通道电流。采用Ba²⁺替换台式液中的Ca²⁺和直接向台式液中加入Ba²⁺（0~8 mmol/L）,观察峰值电流15 min内的变化,数据采用5个以上细胞进行重复。结果：（1）台式液中的Ca²⁺被Ba²⁺替换后,L型钙通道电流的失活速率明显减慢（P<0.01）;在台式液中加入少量Ba²⁺（0.2,0.4 mmol/L）时L型钙通道电流的失活速率无明显改变（P>0.05）,加入0.8 mmol/L Ba²⁺时失活速率明显减慢（P<0.05）。（2）与正常台式液比较,在细胞外液中加入Ba²⁺（0.2,0.4 mmol/L）峰值电流衰减减弱,其中10 min和15 min两个时间点衰减差异明显（P<0.01）。（3）在细胞外液中加入Ba²⁺可下移电流电压曲线,改变翻转电位,减弱丹酚酸A对钙电流的抑制强度,使量效关系曲线右移。结论：在细胞外液中加入一定浓度的Ba²⁺,能够减弱全细胞膜片钳技术记录大鼠心室肌细胞L型钙通道时出现的峰值电流衰减,改变通道的电压依赖特性,影响药物量效关系。     

阿魏酸对糖尿病小鼠心肌病变的影响及其机制

目的：研究阿魏酸对高脂饮食结合小剂量链脲佐菌素（STZ）诱导的2型糖尿病小鼠心肌病变的影响,探讨其可能的作用机制。方法：雄性ICR小鼠20只,高糖高脂饮食连续6周,STZ （30 mg/kg）腹腔注射连续5d后,隔9d测空腹血糖（FBG）,超过11.1 mmol/L视为糖尿病造模成功。将此20只小鼠随机分为模型组、阿魏酸组（200 mg/kg,i.g.）,每组10只;另取10只正常小鼠为对照组;连续给药8周。末次给药后,测定FBG、称体重、全心重和左心室重,计算心脏质量指数（HMI）和左室质量指数（LVMI）;测定超氧化物歧化酶（SOD）活力、丙二醛（MDA）含量;Masson染色观察左心室纤维增生情况;免疫组化法测定心肌组织转化生长因子-β1（TGF-β1）、Ⅲ型胶原蛋白表达。结果：与模型组小鼠比较,阿魏酸组小鼠HMI、LVMI减小（（P<0.01,P<0.05）,心肌组织SOD活力升高、MDA含量下降（P<0.05）;心肌胶原纤维沉积减少,间质纤维化改善;免疫组化显示心肌组织TGF-β1和Ⅲ型胶原蛋白表达减少（P<0.01,P<0.05）。结论：阿魏酸对糖尿病小鼠心肌病变具有保护作用,可能与抗氧化及抑制TGF-β1蛋白表达,减少Ⅲ型胶原蛋白沉积有关。     

环介导等温扩增技术检测食品安全的研究进展

食品安全一直是全世界公众健康的关注焦点。环介导等温扩增(loop-mediated isothermal amplification,LAMP)技术是一种特异性强、灵敏度高、快速简便的等温核酸扩增技术,近年来在核酸检测领域有着广泛的研究和应用。将LAMP技术应用到食品安全检测领域,可以快速准确的监控一些食品安全问题,避免对人类健康所构成的危害。因此针对LAMP技术在食品安全检测方面的优势进行分析,并结合LAMP技术与新兴诊断技术平台的联合运用进行了展望。     

钙库调控的钙通道Orai1体外研究方法的建立

目的:建立钙通道Orai1的体外研究方法。方法:利用脂质体重组技术,将体外纯化的Orai1蛋白重组到脂质体膜上,利用蔗糖密度梯度离心来检测其重组效率及Orai1蛋白在脂质体膜上的结构,并利用钙染料Fura-2检测脂质体内钙离子的释放。结果:成功制备了脂质体及体外纯化了GST-Orai1融合蛋白,蔗糖密度梯度离心结果证明GST-Orai1蛋白成功重组到脂质体上,以及Orai1蛋白以多聚体的形式定位在脂质体膜上。钙离子释放实验证明脂质体内钙离子包装完好,可用于后续Orai1钙通道的功能研究。结论:利用脂质体重组技术建立了一种新的Orai1的研究方法,能够更直接有效地研究其功能及其活化机制。     

Restoration of CD3+CD56+ cell level improves skin lesions in severe psoriasis: A pilot clinical study of adoptive immunotherapy for patients with psoriasis using autologous cytokine-induced killer cells

Psoriasis is a chronic inflammatory skin disorder mediated by the cells and molecules of both the innate and adaptive immune systems. Autologous cytokine-induced killer (CIK) cell infusion is considered an effective and safe cancer treatment and is licensed for this use in China. Accumulated evidence indicating that CD3⁺CD56⁺ cells are significantly decreased in psoriatic patients prompted us to investigate if the restoration of CD3⁺CD56⁺ cells may be beneficial for psoriatic patients. We designed a clinical trial for psoriasis treatment that involved CIK cell infusion because CIK cells include a large amount of CD3⁺CD56⁺ T cells (NCT01894373 at www.clinicaltrials.gov). Six patients with severe psoriasis were initially enrolled, and four of them exhibited markedly lower levels of CD3⁺CD56⁺ cells in their peripheral blood (PB) relative to healthy donors. CIK cell infusion-associated toxicity was not observed in any infusion. The percentage of CD3⁺CD56⁺ cells in the PB markedly increased and the psoriasis area and severity index (PASI) synchronously decreased in four patients with lower CD3⁺CD56⁺ cell contents, and two of them obtained a more than 4-month PASI75 after completing a four-cycle treatment. However, a decrease in the CD3⁺CD56⁺ cells was observed concomitantly with disease recurrence after short-term amelioration. In contrast, no obvious improvement was observed in the two patients with nearly normal CD3⁺CD56⁺ cells in the PB before treatment. These observations suggest that the normalization of the CD3⁺CD56⁺ cell level may improve the skin lesions of severe psoriasis and warrant further clinical trials for severe psoriasis using repeated CIK adoptive immunotherapy.     

Nuclear Receptor Nur77 Facilitates Melanoma Cell Survival under Metabolic Stress by Protecting Fatty Acid Oxidation

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DC-SIGN与mCEACAM1a分子相互作用调控鼠冠状病毒复制

树突细胞特异性细胞间黏附分子-3结合非整合素分子(dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin,DC-SIGN)和肝/淋巴结特异性细胞间黏附分子-3结合非整合素分子(liver/lymph node-specific intercellular adhesion molecules-3-grabbing non-integrin,L-SIGN)是钙离子依赖的C型凝集素受体,通过识别病毒粒子表面含甘露聚糖或果糖寡聚糖的分子介导病毒进入细胞,但其在调节病毒复制中的作用较少被关注。本研究通过建立稳定表达DC-SIGN和L-SIGN及其功能域嵌合体的细胞系,分析两者过表达对鼠冠状病毒复制的影响。结果显示,L-SIGN比DC-SIGN更能显著抑制病毒复制,这种差异与两者胞内区序列和基序组成不同有关;鼠冠状病毒感染导致细胞外信号调节激酶(extracellular signal-regulated kinase,ERK)信号通路分子磷酸化下调,过表达DC-SIGN和L-SIGN可抑制这种下调趋势。在没有鼠癌胚抗原相关细胞黏附分子1(mouse carcinoembryonic antigen-related cell adhesion molecule 1,mCEACAM1)存在时,DC-SIGN不能介导病毒感染。这些结果提示,DC-SIGN通过与mCEACAM1a分子相互作用和调节细胞信号通路分子功能以调控鼠冠状病毒复制。     

水牛卵巢黄体形成和退化的蛋白质表达谱构建及生物信息学分析

本研究构建了水牛卵巢黄体形成及退化过程的定量蛋白质表达谱,从中寻找与水牛发情周期相关的重要蛋白质。为研究水牛卵巢周期性变化的分子机制提供蛋白质水平的数据支撑,进而为提高水牛繁殖效率奠定实验基础。以水牛排卵后的红体期(corpus hemorrhagicum,CH)、黄体期(corpus luteum,CL)和白体期(corpus fibrosum,CF)的卵巢作为研究对象,利用串联质谱标签(tandem mass tag,TMT)标记结合液质联用((liquid chromatography/mass spectrometry,LC-MS/MS)的定量蛋白质组学技术,采用相关软件对得到的差异表达蛋白质进行生物信息学分析。同时对与水牛发情周期相关的重要差异蛋白质:单核巨噬细胞分化抗原(CD14)、通用转录因子Ⅱ-Ⅰ(GTF2I)、羟基类固醇(17β)脱氢酶1(HSD17B1)、U6 sn RNA相关Sm样蛋白质(LSM1)和纤溶酶原激活物抑制物(SERPINE1)进行了qRT-PCR分析验证。结果显示,共鉴定得到2 343种蛋白质,其中差异表达蛋白质有284种(差异倍数≥2.0),初步构建了水牛卵巢黄体形成和退化的定量蛋白质表达谱。对其中的五种重要差异蛋白质(CD14、GTF2I、HSD17B1、LSM1和SERPINE1)进行qRT-PCR验证,结果有四种(CD14、HSD17B1、LSM1和SERPINE1)的qPCR结果与质谱结果相一致,仅GTF2I与质谱结果不一致,可能是由于GTF2I存在转录后调控。本研究首次从蛋白质水平对水牛卵巢排卵后的周期性变化的分子机制进行了探究,同时为其他家畜品种发情周期的研究提供了新的研究思路。     

自发性高血压大鼠血管平滑肌细胞的精氨酸转运和脂质体对转运的影响

本工作在培养的自发民生高血压大鼠和对照ＷＫＹ大鼠的主动脉平滑肌细胞上,观察细胞Ｌ－精氨酸转动转征,并观察脂质体作为Ｌ－Ａｒｇ载体对Ｌ－Ａｒｇ细胞转运的影响。     

Methane emission from Texas rice paddy soils. 2. Seasonal contribution of rice biomass production to CH4 emission

Measurements focused on seasonal contribution of rice productivity to methane emission were made in three experiments conducted in Texas flooded paddy soils during 1994 and 1995 growing seasons. A total of five rice cultivars representing two distinct groups in methane emission were involved. Over a 10-week period after permanent flooding, total seasonal methane emission was positively correlated with rice above-ground biomass ( r ² = 0.845, n = 11). A very strong dependence of daily methane emission on above-ground vegetative biomass ( r ² = 0.887, n = 93) and on root biomass ( r ² = 0.816, n = 33) was also observed. Calculation from three developmental periods (vegetative, reproductive and ripening) of rice plant indicated that more than 75% of total seasonal methane was emitted during the last 5-week period in concert with reproductive and ripening stages, while rice biomass production during the same period amounted to ≈ 50% of the seasonal total. According to the correlation of cumulative methane emission with above-ground biomass increment between every two-week interval ( r ² = 0.490, n = 93, P = 0.000), the carbon released as methane is approximately equivalent to 3% and 4.5% of photosynthetically fixed carbon in the biomass for low and high emission cultivars, respectively. A further investigation showed that these fractions are related to plant growth and development. The carbon ratio of methane emitted to net photosynthetic production during vegetative, reproductive, and ripening periods averaged 0.9%, 3.6% and 7.9%, respectively, for low emission cultivars, and 2.0%, 5.0% and 8.3%, respectively, for high emission cultivars. Moreover, the ratio was strongly dependent on plant biomass, resulting in r 2 values from 0.775 to 0.907.