银杏叶提取物、肌酸和氨哮素延缓去神经骨骼肌萎缩的实验研究

目的　研究银杏叶提取物 (extractsofGinkgobiloba ,EGb76 1)、肌酸和氨哮素延缓去神经骨骼肌萎缩的效果及其机制。　方法　复制大鼠臂丛神经损伤动物模型 ,2 4只SD大鼠随机分为EGb76 1组、肌酸组、氨哮素组和对照组 ,分别以相应药物 ( 10 0mg·kg 1·d 1)及等渗盐水灌胃 ,5周后检测各组臂围、肌湿重、肌肉总蛋白含量 ,用末端转移酶介导的dUTP缺口末端标记法 (TdT -me diateddUTPnickendlabeling,TUNEL)检测萎缩肌肉中的细胞凋亡 ,用免疫组织化学染色及灰度分析检测肌细胞中fas、FLICE/Caspase8表达的变化。　结果　EGb76 1、肌酸和氨哮素不同程度地抑制去神经骨骼肌萎缩大鼠的臂围、肌肉湿重和肌肉总蛋白含量的降低 (P <0 .0 5 ) ,减少萎缩肌肉中的TUNEL染色阳性细胞数以及细胞中的fas、FLICE/Caspase8含量 (P <0 .0 1)。　结论　EGb76 1、肌酸和氨哮素能够有效地延缓去神经骨骼肌萎缩 ,其机制可能与抑制肌细胞凋亡有关。     

Effects of Ginkgo biloba on exhaled nasal nitric oxide during normobaric hypoxia in humans

Ginkgo biloba, an extract of the ginkgo tree, may prevent or lessen symptoms of acute mountain sickness in humans. The mechanism of this effect is poorly understood. One hypothesis is that ginkgo alters nitric oxide (NO) metabolism, possibly by scavenging NO or altering nitric oxide synthase expression and thereby lessening the vasodilatory effects of NO. To date, an effect of Ginkgo biloba on NO metabolism has not been demonstrated in humans. We measured exhaled nasal NO output in humans (n = 9) during normoxia and then during acute normobaric hypoxia (goal oxyhemoglobin saturation 75% to 85%) before and after administration of a standardized extract of Ginkgo biloba (120 mg twice daily for 5 days). Oxygen saturation, heart rate, and minute ventilation were similar before and after Ginkgo biloba administration. Exhaled nasal NO output was increased during normoxia following ginkgo (p < 0.02) and reduced during normobaric hypoxia both before (p < 0.02) and following (p < 0.003) ginkgo. Exhaled nasal NO output during normobaric hypoxia was lowest following ginkgo (p < 0.003). We conclude that Ginkgo biloba increases exhaled nasal NO output during normoxia and enhances reduced exhaled nasal NO output during normobaric hypoxia. Our results suggest that Ginkgo biloba may act to reduce AMS through an effect on NO metabolism.     

银杏叶提取物对氯吡格雷人体内药动学影响

  目的 探讨银杏叶提取物对氯吡格雷人体内药动学影响及其相关机制。方法 选取14名健康男性志愿者,第一阶段服用氯吡格雷150 mg/d(单用药组);第二阶段进洗脱期后,受试者连续服用银杏叶提取物240 mg/d,连续14 d,第14天给予银杏叶提取物1 h后,再空腹服用氯吡格雷(联用药组)。两组均在给药后采集受试者0~24 h外周静脉血,检测氯吡格雷代谢产物SR-26334的浓度。此外,建立体外Caco-2细胞模型,以罗丹明-123和维拉帕米分别为阴性和阳性对照,采用流式细胞技术检测银杏叶提取物和氯吡格雷对Caco-2细胞内的荧光强度的影响。结果 联合用药组受试者血中SR26334的AUC_(0-t)(3192.3±45.035)[(mg·h)/L]、AUC_(0-∞)(3343.017±43.829)[(mg·h)/L]和C_max(340.988±11.257)[(mg·h)/L]均高于单独用药组,CL/F(0.071±0.007)低于单独用药组(P<0.05)。Caco-2细胞内荧光强度,银杏叶提取物组(487±14.12)和联合用药组(497±17.22)高于阴性对照组(P<0.05)。结论 银杏叶提取物能显著提高氯吡格雷羧酸在人体内的生物利用度和吸收总量,其作用机制可能与银杏叶对P-糖蛋白(P-gp)的抑制作用有关。     

不同低温冷冻预处理对异体神经移植再生影响的实验研究

目的 观察不同冷冻温度下保存的异体神经对周围神经缺损修复的效果.方法 取96只同种属雄性大鼠,其中24只为取材组,72只随机分为对照组(A、B组)和实验组(C、D、E、F组),每组12只.A组为新鲜自体神经移植组,B组为新鲜异体神经移植组,C、D、E和F组分别为经4℃、-50℃、-80℃和-196℃甘油保存3周的神经移植组.术后2周,进行免疫组织化学观察;术后9、16周进行大体观察、光镜检察、电生理测定.结果 术后2周,B组移植段见明显T淋巴细胞浸润,C、D、E组次之,A组及F组末见T淋巴细胞.术后9周及16周,从神经再生效果评价看:A组神经再生效果最好,F组次之,C、D、E组再次,B组最差.结论 在各冷冻组中,以-196℃组神经再生效果最好,接近新鲜自体神经移植组.     

胃饲己酮可可碱预处理对大鼠肝脏缺血再灌注损害时细胞凋亡的影响

目的探讨胃饲己酮可可碱预处理对大鼠肝脏缺血再灌注损害时细胞凋亡的影响及其对肝功能的保护作用。方法 48只健康成年雄性SD大鼠随机分为生理盐水对照组（n=24）和己酮可可碱预处理组（n=24）,两组分别给予生理盐水或己酮可可碱溶液灌胃5d。建立肝脏缺血再灌注模型,分别于缺血30min及再灌注后1、6、24h各时相点取材,检测血清丙氨酸氨基转移酶（ALT）、肝组织丙二醛（MDA）、超氧化物歧化酶（SOD）,并用TUNEL染色及图像分析法检测肝细胞凋亡率的变化。结果与生理盐水对照组比较,己酮可可碱预处理组ALT、MDA、肝细胞凋亡率在上述多个时相点显著降低（P〈0.05）,而SOD活性则显著升高（P〈0.05）。结论肝脏缺血再灌注前给予己酮可可碱预处理,可以显著降低肝细胞凋亡率,减少MDA含量同时激活SOD,并能有效地保护肝脏功能。     

Sonography guided percutaneous radiofrequency ablation of hepatocellular carcinoma: effect of cooperative training on the pretreatment assessment of the operation's feasibility

OBJECTIVE: The aim of this study is to investigate the effects of cooperative training on the pretreatment assessment of the feasibility to perform Ultrasonography (US) guided percutaneous radiofrequency ablation for patients afflicted with hepatocellular carcinoma. MATERIALS AND METHODS: In our prospective study, 146 patients with 200 hepatocellular carcinomas were referred for radiofrequency ablation after triage by hepatologists. Three radiologists with different levels of experience performed the planning US before (group I) and after (group II) cooperative training, to evaluate whether radiofrequency ablation was feasible. The feasibility rates considered eligible according to our criteria were evaluated. In addition, we analyzed the reasons for the lack of feasibility were analyzed. The interobserver agreement for the assessment of feasibility before and after training was also calculated. RESULTS: The overall feasibility rates for both groups was 73%. No significant difference in the feasibility rates was observed. The feasibility rates of each observer for group I were 71% (observer 1), 77% (observer 2) and 70% (observer 3) and those for group II were 73%, 76% and 69%, respectively. In the tumors (n = 164) considered ineligible, the two most common causes for refraining from performing radiofrequency ablation included non-visualization of the tumor (62%) and the absence of a safe route for the percutaneous approach (38%). We found moderate interobserver agreement for all observers before cooperative training and a good agreement after training. CONCLUSION: Although the cooperative training did not affect the feasibility rate of each observer, it improved the interobserver agreement for assessing the feasibility of performing US guided radiofrequency ablation, which may reduce unnecessary admission or delayed treatment.     

Radioprotective efficacy of Ginkgo biloba and Angelica archangelica extract against technetium-99m-sestamibi induced oxidative stress and lens injury in rats

Purpose: Technetium-99m is a radioactive tracer that emits gamma rays. Its half-life time is 6?h. Similar to other ionizing radiations, the main mechanism of radiation-induced effects is initiated through the production of reactive oxygen species (ROS). This study was designed to determine the possible protective effects of Ginkgo biloba and Angelica archangelica against oxidative organ damage that was induced by ^99mTc-sestamibi.

Materials and methods: The experiments were performed on thirty-six Wistar-rats which were subdivided into control groups and groups exposed to ^99mTc-sestamibi. The irradiated groups were either untreated or pre-treated with G. biloba or A. archangelica. For all groups, the levels and/or activities of Catalase (CAT), Glutathione (GSH), Malondialdehyde (MDA) and Superoxide-dismutase (SOD) were measured in blood and lenses. The soluble/insoluble protein ratio was determined and lens-protein profiles were obtained via Sodium-Dodecyl-Sulfate Polyacrylamide Gel-Electrophoresis (SDS-PAGE).

Results: There were no significant difference between the pre-treated and irradiated G. biloba group and control group, while both groups were significantly different (p?A. archangelica did not confer any significant protection against ^99mTc-sestamibi induced toxicity.

Conclusions: This study demonstrated that G. biloba, through its free radical scavenging and antioxidant properties, successfully attenuated ^99mTc-sestamibi radiation-induced oxidative organ injury. The latter is a crucial factor of cataractogenesis in rats, suggesting that G. biloba may have a potential benefit in the protection against radiopharmaceuticals.     

猴骨髓间充质干细胞的分离及原代培养特性的研究

目的：探讨猴骨髓间充质干细胞(MSCs)低分化干细胞方面的特性。方法：以Percoll(质量密度1073g/L)非连续密度梯度离心分离出骨髓悬液中的骨髓间充质干细胞，用含100mL/L胎牛血清的DMEM培养液培养，观察细脑的形态、生长状况及其超微结构。结果：原代培养的骨横间充质干细胞增殖缓侵，细胞增殖率和形态分化不均一。如有一些细脑在4wk的培养时间内末见明显增殖，这些增殖不明显的细胞有的未见明显的伸展，呈圆形，有的伸展充分，成片状；在培养2wk后也可见一些明显增殖的细胞，分别形成克隆团状或条状的增生细胞群；培养过程中可见有神经元样及多核细胞出现。原代培养的骨髓间充质干细胞的超微结构也显示了低分化的干细胞特点，如细胞表面具有微绒毛，脑浆内内质网丰富、激离核糖体数量多、线粒体小，核仁大而不规则、可见核裂，超微结构还显示了一些中胚层来源于细瘤的结构特点，如大量的微丝。结论：经Percoll细胞分离介质分离出的骨髓间充质干细胞，在非诱导条件下原代培养过程中，从形态分化、增殖率等方面显示了其多向分化潜能；从超微结构等方面显示了其中胚层来源低分化细胞的特点。这些特点可作为骨髓间充质干细胞鉴定的佐证之一，说明Percoll非连续密度梯度离心法对骨髓间充质干细胞的分离具有可靠性。     

运动性疲劳的线粒体膜分子机制研究.Ⅰ.急性力竭运动中线粒体电子漏引起质子漏增加及其相互作用

以大鼠渐增负荷力竭性跑台跑为运动性疲劳模型，观察了运动后大鼠骨骼肌线粒体电子漏和质子漏的变化。测定线粒体超氧阴离子生成量和脂质过氧化水平。分别测定线粒体以苹果酸＋谷氨酸和以琥珀酸为底物的态4呼吸、态3呼吸、呼吸控制比及磷氧比。结果表明，运动性疲劳状态下大鼠骨骼肌线粒体超氧阴离子生成增加，脂质过氧化水平也显著增加；以苹果酸十谷氨酸或以琥珀酸为底物的态4呼吸速率明显加快，呼吸控制比、磷氧比显著下降。结果提示，力竭性运动后下大鼠骨骼肌线粒体电子漏导致线粒体质子漏增多，是运动性疲劳状态下线粒体氧化磷酸化偶联程度下降的重要因素。实验结果支持电子漏引起质子漏的假说。     

EBOV三聚体糖蛋白在新型糖基工程酵母中的表达与纯化

目的 用新型糖基工程酵母表达并纯化得到具有类似哺乳动物细胞糖基化修饰的埃博拉病毒三聚体糖蛋白(EBOV-GP),为其亚单位疫苗研究提供基础.方法 人工合成EBOV-GP基因,将编码全长EBOV-GP基因和编码缺失黏蛋白样域(MLD)与穿膜区的EBOV-GPΔMLDΔTM基因分别克隆到pPICZ-αA载体上,电转化糖基工程酵母,与在HEK-293T细胞中表达的EBOV-GP进行比较,利用PNGaseF和EndoH酶切分析其糖基化修饰,利用亲和层析与离子交换层析纯化目的蛋白,蛋白质N端测序分析其在蛋白翻译修饰过程中是否正确切除了信号肽,同时利用凝胶柱分析是否能形成三聚体结构.结果 PNGaseF酶切结果显示,用糖基工程酵母和HEK-293T细胞表达的EBOV-GP糖蛋白相对分子质量大小与N-糖基化程度均一致,EndoH酶切显示EBOV-GPΔMLDΔTM的N-糖基化修饰是非高甘露糖形式的复杂型糖基化修饰;经三步纯化得到的目的蛋白,N端测序显示为GP蛋白成熟肽序列,其自身信号肽被正确切除;凝胶柱分析显示纯化得到的目的蛋白以三聚体形式存在.结论 用糖基工程酵母表达制备了具有复杂型糖基化修饰的EBOV-GP.