Bleomycin in octaarginine-modified fusogenic liposomes results in improved tumor growth inhibition

Bleomycin (BLM) is an example of an anticancer drug that should be delivered into cytosol for its efficient therapeutic action. With this in mind, we developed octaarginine (R8)-modified fusogenic DOPE-liposomes (R8-DOPE-BLM). R8-modification dramatically increased (up to 50-fold) the cell-liposome interaction. R8-DOPE-liposomes were internalized via macropinocytosis and did not end up in the lysosomes. R8-DOPE-BLM led to a significantly stronger cell death and DNA damage in vitro relative to all controls. R8-DOPE-BLM demonstrated a prominent anticancer effect in the BALB/c mice bearing 4T1 tumors. Thus, R8-DOPE-BLM provided efficient intracellular delivery of BLM leading to strong tumor growth inhibition in vivo.     

消痰散结方对荷S180肉瘤小鼠蛋白质代谢的影响

目的运用荷S180小鼠模型,观察消痰散结方改善肿瘤蛋白质代谢状况的作用,探索其作用机制。方法将40只小鼠随机分为消痰散结方组（A组）、化疗（喃氟啶）组（B组）、0.9%氯化钠溶液组（C组）,对照组（D组）,前三组进行S180肉瘤皮下接种造模;4周后,观察各组体重,血清生化检测总蛋白、白蛋白和C-反应蛋白（CRP）水平,免疫组化观察骨骼肌结构及骨骼肌NF-κB的表达。结果消痰散结方可升高荷瘤鼠血清总蛋白、白蛋白水平,下调血清CRP水平,对骨骼肌结构具有保护作用。结论消痰散结方可以改善肿瘤蛋白代谢状况,其可能途径是通过调节肝脏的蛋白代谢。     

长期口服卡托普利对小鼠脑组织自由基及相关酶的影响

目的:探讨长期口服卡托普利对小鼠脑组织自由基及相关酶的影响,为其临床应用提供实验依据。方法:取30只小鼠,随机均分为正常对照组(水)和卡托普利组(卡托普利,11.08～14.92mg·kg-1·d-1),按饮水给药方式连续给药14周,测定脑组织中自由基与相关酶(丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、钠-钾泵三磷酸腺苷酶(Na+-K+-ATP酶)、钙-镁泵三磷酸腺苷酶(Ca2+-Mg2+-ATP酶))水平。结果:与正常对照组比较,卡托普利组小鼠脑组织中MDA水平降低(P<0.05);SOD、GSH-Px水平均无明显变化;Ca2+-Mg2+-ATP酶、Na+-K+-ATP酶活性有降低的趋势,但无统计学意义。结论:长期口服卡托普利可减少脑组织自由基含量,增强机体抗氧化能力,但脑组织神经细胞膜功能有受损的可能。     

e4声动力治疗小鼠S180肉瘤的实验研究

 目的： 本文研究超声激活声敏剂e4对在体小鼠S180肉瘤的杀伤作用。方法：荷瘤小鼠腹腔注射e4(40mg/kg),6小时后用频率为1.0MHz超声波照射肿瘤区域180s, 超声强度分3组：0.4W/cm², 0.8W/cm²,1.6W/cm²。以空白对照组,单纯超声组（超声强度为1.6W/cm²）,单纯声敏剂组为对照组,每两天测量肿瘤大小,12天后剥离肉瘤并称重比较。结果 ：e4在小鼠体内经超声激活后可明显抑制肿瘤生长。在超声强度为0.4W/cm²～0.8W/cm²范围时,e4对肿瘤的抑制作用随声强的增加疗效亦增加。结论 ：e4声动力治疗对小鼠S180肉瘤有明显杀伤或抑制作用,在一定范围内其作用大小与超声强度正相关。声动力疗法有望成为临床治疗肿瘤的新方法。     

野马追对大、小鼠实验性高脂血症的防治作用

目的探讨野马追提取液对大、小鼠实验性高脂血症的防治作用。方法将大鼠和小鼠各60只分别随机分为大、小鼠空白对照组、高脂模型组、阳性对照组及野马追提取液高、中、低剂量组。除空白对照组外,小鼠各组给予相应的药物30d后腹腔注射75%蛋黄乳,大鼠各组喂高脂饲料同时给予相应的药物30d。各组均于末次给药后采血,测血清胆固醇、甘油三酯及高、低密度脂蛋白胆固醇(HDL-C、LDL-C)含量。结果野马追能明显降低实验性血清胆固醇、甘油三酯及LDL-C水平,并明显升高HDL-C水平。结论野马追对实验性大、小鼠高脂血症有明显防治作用。     

视网膜特异性表达人血管内皮生长因子 基因载体的构建

目的构建在视网膜组织特异性表达的人血管内皮生长因子（VEGF）₁₆₅基因。方法用聚合酶链反应(PCR)方法从BLAB/C鼠全基因组扩增能在视网膜组织特异性表达的rho启动子，经限制性内切酶纯化后克隆于质粒pcDNA^3.1+-VEGF₁₆₅中，建立重组质粒pcDNA^3.1+-rho-VEGF₁₆₅，通过限制性内切酶酶切分析及PCR鉴定筛选出正确重组质粒pcDNA^3.1+-rho-VEGF₁₆₅,由jetPEI介导转染人视网膜色素上皮细胞和人脐静脉内皮细胞，并通过免疫组织化学染色以及绘制细胞生长曲线检测在人视网膜色素上皮细胞和人脐静脉内皮细胞中VEGF蛋白的表达。结果在人视网膜色素上皮细胞中，重组质粒pcDNA^3.1+-rho-VEGF₁₆₅比质粒pcDNA^3.1+-rho-VEGF₁₆₅的VEGF蛋白表达强，在人脐静脉内皮细胞，两者的表达量无明显差别。结论pcDNA^3.1+-rho-VEGF₁₆₅载体的构建为进一步研究VEGF在视网膜新生血管形成中的致病机理提供基础材料，并为进一步建立视网膜特异性表达VEGF转基因鼠模型建立了基础。(中华眼底病杂志,2005,21:106-109)     

奥曲肽抑制视网膜新生血管形成的实验研究

目的　探讨生长抑素类似物奥曲肽对视网膜新生血管形成的影响及其治疗作用。方法　将鼠龄7d的小鼠40只随机分为5组,每组8只。正常对照组于正常空气环境中饲养,不予任何处理;其他4组置于氧箱中饲养。实验组分别皮下注射奥曲肽20和50μg·kg-1·d-1,实验对照组皮下注射等量PBS,连续用药5d,高氧组不注射奥曲肽。将鼠龄17d的小鼠处死,摘除眼球制作标本,进行组织病理学及电镜观察。光镜下观察并计数突破视网膜内界膜的血管内皮细胞核数。原位杂交法检测生长抑素受体2(SSTR2)在视网膜上的表达。电镜下观察视网膜组织超微结构的改变。结果　正常对照组标本HE染色几乎未见突破内界膜的血管内皮细胞核,高氧组和实验对照组可见较多的突破内界膜的血管内皮细胞核,而实验组的数目明显少于高氧组和实验对照组。SSTR2原位杂交染色可见正常对照组、高氧组、实验对照组视网膜神经节细胞层、内核层及血管内皮细胞SSTR2强阳性表达,实验组呈弱阳性表达,其中大剂量实验组的表达更弱于小剂量实验组。电镜下可见缺氧引起小鼠视网膜视细胞层的破坏,奥曲肽治疗后,视网膜超微结构的损害明显好转。结论　奥曲肽能有效抑制视网膜新生血管的形成,在一定程度上可预防缺氧造成的视网膜超微结构的损害。     

生长抑素类似物抑制胆管癌细胞增殖的研究

目的探讨生长抑素类似物奥曲肽(OCT)对人胆管癌细胞细胞株QBC939的抑制作用及可能的作用机制。方法四氮唑蓝(MTT)法检测OCT对人胆管癌细胞株QBC939增殖的影响,流式细胞仪检测OCT对细胞周期变化的作用,免疫组织化学法研究OCT对人胆管癌细胞株QBC939P27KIP1蛋白表达变化的影响。建立胆管癌裸鼠模型,进一步探讨生长抑素的作用。结果MTT法检测不同浓度OCT(5、0.5、0.05、0.005mg/L)作用于QBC93948h后,实验组0.5、5mg/L组和对照组吸光度(A)值比较差异有统计学意义(P<0.05)。细胞生长率分别为83.80%,80.28%,77.53%,65.32%。流式细胞仪分析显示不同浓度OCT作用于QBC93948h后,G0/G1期细胞明显增多(P<0.05)。免疫组织化学P27KIP1蛋白表达随OCT浓度的增加而增强(P<0.05)。建立胆管癌裸鼠模型后,OCT干预21d后实验组瘤重明显小于对照组(P<0.05)。结论OCT可抑制人胆管癌细胞的增殖。在一定范围内呈剂量依赖性,其抗肿瘤作用机制主要是通过细胞周期阻滞来实现的,而这一作用的实现可能与P27KIP1蛋白表达的上调有关。     

Improvement of episodic contextual memory by S 18986 in middle-aged mice: comparison with donepezil

Introduction This study compared the effects of S 18986, a positive allosteric modulator of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors, to those of donepezil a cholinesterase inhibitor on memory impairments induced by ageing in a contextual serial discrimination (CSD) task in middle-aged mice. Materials and methods The CSD task involved the learning of two consecutive discriminations in a four-hole board, each performed on two different floors. This model has been developed to study simultaneously different forms of memory in mice (i.e., episodic-like vs semantic-like forms of memory). We showed that placebo-middle-aged mice (14–15 months old) and placebo-aged subjects (19–20 months old) exhibited a severe memory deficit for the first but not the second discrimination, which was due to an increase in interference, as compared with placebo-treated young mice (5 months old). Middle-aged mice were given (9 days) per os administration of either donepezil, S 18986, or placebo. Results and discussion Both 0.3 mg/kg donepezil and 0.1 mg/kg S 18986 reversed the deficit of middle-aged mice through a significant increase in contextually correct responses and in parallel a tendency to reduce interfering responses. Conclusion Overall, S 18986 emerges as having a beneficial impact on contextual memory processes in middle-aged mice.     

Effects of naloxone and diprenorphine on spontaneous activity in rats and mice

The narcotic antagonist naloxone has been reported to decrease locomotor activity in the rat, presumably by blocking endogenous opiate systems. Naloxone has a greater affinity for receptors which preferentially bind morphine and other opiate alkaloids as compared to receptors that bind endogenous opioid peptides. Diprenorphine, another pure opiate antagonist, binds with equal affinity to both receptor subtypes. Therefore, the effects of the narcotic antagonists naloxone and diprenorphine on spontaneous activity were compared in rats and mice, tested individually and in pairs. Only naloxone (10 mg/kg) affected spontaneous activity in rats tested individually, decreasing both gross and fine activity. In rats tested in pairs, naloxone (1.0 and 10 mg/kg) decreased both fine and gross activity, while diprenorphine (10 mg/kg) produced significant decreases only in fine activity. In mice tested individually, naloxone produced modest (nonsignificant) decreases in activity while diprenorphine (10 mg/kg) significantly enhanced activity. Neither opiate antagonist produced consistent effects on activity in paired mice. These results illustrate the species and situation dependence of the effects of opiate antagonists and point out the need for testing more than one narcotic antagonist in research designed to provide inferential information concerning possible physiological functions of endogenous opioid peptides.