小鼠Tim-2基因在L929细胞表达后促进铁蛋白的内吞

目的获取BALB／c小鼠T细胞免疫球蛋白域．黏蛋白域蛋白-2（T cell immunoglobulin and mucin domain containing molecules-2，Tim-2）基因，构建真核表达载体在L929细胞中表达并研究其功能。方法RT-PCR获取BALB／c小鼠Tim-2基因，T-A克隆后经测序鉴定后酶切，插入pEGFP-N1真核表达载体，脂质体转染L929细胞，荧光显微镜观察外源基因的表达，然后加入铁蛋白与转染细胞作用。结果外源基因在L929细胞中得到高效表达，荧光显微镜的结果显示，外源基因定位于细胞膜上，并能促进细胞对铁蛋白的内吞。结论Tim-2基因在真核细胞中表达后定位于细胞膜上，并促进细胞对铁蛋白的内吞。     

HBV preS2起始区反义核酸对人肝癌细胞在裸鼠体内生长的抑制作用

PCR合成互补于HBVpre－S2起始区的反义寡核苷酸（as-preS2），以HBVDNA转染的HepG2．2．15细胞接种裸鼠制备人肝癌模型，通过连续用药、一次性用药、混合用药等三种途径研究其对人肝癌裸鼠模型的抑瘤生长及体内抗HBV作用。流式细胞要（FCM）分析asON诱导瘤细胞凋亡作用，ELLSA法检测反核酸作用鼠血清中HBV抗原含量的变化。结果显示，一次性与混合用药组裸鼠均表现为成瘤潜伏期瞎工，成瘤率明显低于瘤细胞对照未用药组（P＜0．05），瘤体生长缓慢。裸鼠瘤内连续用药，在48hFCM测凋亡峰值为39．57％，S期细胞降低显著，生理盐水与无关序列对照分别为7．92％110．89％，提示as-preS2可能诱导S期细胞凋亡。as-preS2荷瘤鼠HBeAg和HBsAg的抑制率分别为45％和65％。提示，as-preS2可有效抑制体内HBV抗原表达，对人肝癌裸鼠在体内的生长有明显的抑制作用。     

Antioxidant enzymes and lipid peroxidation in C57Bl/6 and BALB/c mice

Superoxide dismutase and catalase activities and levels of thiobarbituric acid-reactive lipid peroxidation (LPO) products were estimated in the liver of C57B1/6 and BALB/c mice. The results indicate that although antioxidant enzymes are more active in BALB/c mice, compensation of oxidation processes in this strain is possible only if LPO-inducing agents are absent or present at low levels, and that these agents, including exogenous ones, may be expected to activate lipid oxidation in this strain to a greater extent than in C57Bl/6 mice. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 12, pp. 580–583, December, 1995     

Pathogenic autoimmunity to affinity-purified mouse acetylcholine receptor induced without adjuvant in BALB/c mice

Myasthenia gravis (MG) and experimental autoimmune myasthenia gravis (EAMG) are antibody-mediated disorders in which anti-acetylcholine receptor (anti-AChR) antibodies cause loss of muscle AChR and subsequent weakness. Many species are susceptible to induction of EAMG with purified xenogeneic AChR in adjuvant, but injection of Torpedo AChR without adjuvants can also induce evidence of EAMG. To see whether pathogenic autoimmunity could be induced in mice by isolated mouse AChR we injected BALB/c mice with several doses (1 pmole; about 0.1 ug) of affinity-purified AChR (from the BC3H1 cell line but thought to be identical with denervated mouse muscle) intraperitoneally, without adjuvant, over a period of 10-22 weeks. Some of the mice became ill and died. High levels of serum anti-mouse AChR, directed mainly towards the main immunogenic region, were found and, in the survivors, correlated with loss of muscle AChR. Thus BALB/c mice can mount an autoimmune response to minute amounts of mouse AChR, without the use of adjuvants, and this response is very similar to that found in MG. This novel finding has implications regarding the etiology of the human disease.     

小肠结肠炎综合征小鼠肠黏膜中NLRP3表达与炎症分子关系的研究

目的 探讨食物蛋白诱导的小肠结肠炎综合征（FPIES）小鼠肠黏膜细胞中炎症小体NOD样受体热蛋白结 构域相关蛋白3（NLRP3）表达水平,明确NLRP3异常与炎症分子及细胞焦亡的关联性。方法 利用卵清蛋白灌胃建 立食物蛋白诱导FPIES小鼠模型;实时荧光定量聚合酶链反应（qPCR）和Western blot方法检测肠黏膜细胞NLRP3、 炎症分子及细胞焦亡通路分子的表达水平;采用药物干预黏膜细胞,分别抑制和激活NLRP3,Western blot方法检测 肠黏膜细胞炎症分子及细胞焦亡通路分子表达的改变情况。结果 FPIES小鼠肠黏膜细胞中NLRP3、炎症分子及细 胞焦亡通路分子表达水平显著上调（P＜0.05）;激活NLRP3表达,可以诱导炎症分子及细胞焦亡通路分子表达显著 上调,抑制NLRP3表达,可以显著上调炎症分子转化生长因子（TGF）-β和肿瘤坏死因子（TNF）-α表达（P＜0.05）。结论 FPIES小鼠肠黏膜细胞NLRP3表达与炎症反应及细胞焦亡密切相关,是调控FPIES肠道病理表型的上游靶标分子。     

Radio-adaptive response to environmental exposures at Chernobyl

The genetic consequences resulting from environmental exposure to ionizing radiation have a significant impact on both radiation regulatory policies and the comprehension of the human health risks associated with radiation exposure. The primary objectives of the study were to assess 1) genotoxicity of exposure to radiation as a function of absorbed dose and dose rate, and 2) induction of a radio-adaptive response following a priming dose at varying dose rates. Results demonstrated that sub-acute environmental exposures of 10cGy gamma radiation resulted in indistinguishable levels of chromosomal damage as compared to controls. A radio-adaptive response was observed in all experimental groups, exposed to a subsequent acute challenge dose of 1.5 Gy, demonstrating that low dose rates of low energy transfer (LET) radiation are effective in reducing genetic damage from a subsequent acute low-LET radiation exposure. Furthermore, the data presented herein demonstrate a potential beneficial effect of sub-chronic exposure to low levels of low-LET radiation in an environmental setting and do not support the Linear No Threshold (LNT) hypothesis.     

NADPH-diaphorase histochemistry reveals heterogeneity in the distribution of nitric oxide synthase-expressing interneurons between olfactory glomeruli in two mouse strains

The expression of nitric oxide synthase (NOS) in the olfactory bulb was compared between two mouse strains, CD-1 and BALB/c, that differ in the connectivity within their olfactory glomeruli, their content of tyrosine hydroxylase, and their response to olfactory deafferentation. Labelled cells were qualitatively and quantitatively analyzed by both immunohistochemistry for NOS and histochemistry for nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase (ND). Both periglomerular cells and short-axon cells were observed with both techniques employed, and their colocalization in the same neurons demonstrated that ND is a reliable marker for NOS-expressing cells in the mouse olfactory bulb (OB). The histochemical technique differentiates two types of glomeruli: ND-positive and ND-negative. Olfactory glomeruli in the CD-1 strain were about 7% larger than those in the BALB/c animals. While the density of NOS/ND-containing periglomerular cells was similar between both strains studied, more NOS/ND-labelled cells were observed in the ND-positive glomeruli (P = 0.002). Since periglomerular cells in the BALB/c strain do not receive direct olfactory receptors synapses, the present results indicate that such inputs do not regulate the expression of NOS and ND activity in the periglomerular cells. The different densities of NOS/ND-expressing periglomerular cells may indicate that nitric oxide is implicated in a differential modulation of the odor response within both types of chemically distinct glomeruli in the mouse olfactory bulb. J. Neurosci. Res. 53:239–250, 1998. © 1998 Wiley-Liss, Inc.     

Leishmanicidal and trypanocidal activity of extracts and secondary metabolites from basidiomycetes

Seventeen extracts and seven secondary metabolites isolated from basidiomycetes were tested in medium culture against promastigote forms of Leishmania spp. and bloodstream forms of Trypanosoma cruzi. Extracts from the culture filtrate or mycelium were generally inactive against the parasites except the Zucoagaricus genus mycelium extract which reduced by 47% the number of bloodstream forms. Striatin A, striatin B and podoscyphic acid exhibited in vitro activity at 10, 5 and 100 μg/mL, respectively. One compound showed activity against bloodstream forms of T. cruzi, the sesquiterpenoid naematolin, lysing the parasites by 79%. BALB/c mice infected with L. amazonensis were treated 3 weeks post-infection with striatin A and striatin B by subcutaneous route for 15 days at 10 mg/kg daily. The reference drug, N-methylglucamine antimonate, administered by subcutaneous injections at 28 mg Sbv/kg/day for 15 days reduced the parasite burden by 71.2% (p <0.05). Subcutaneous administration of straitin A at 10 mg/kg produced a weak decrease of the parasite burdens in the footpad by 17.6%. The treatment with striatin B had no effect and showed higher toxicity than striatin A. © 1997 John Wiley & Sons, Ltd.     

肾上腺皮质激素对病毒性心肌炎小鼠免疫状态的调控作用

目的：研究病毒性心肌炎时应用肾上腺皮质激素治疗对机体免疫指标的调控作用。方法：随机将240只4周龄BALB／c小鼠等分为正常对照组、激素对照组、病毒对照组、早期激素治疗组、中期激素治疗组和晚期激素治疗组,每组40只。正常对照组每只小鼠腹腔接种0．1ml不含病毒的Eagle’s液,其他组每只小鼠均腹腔接种0．1ml 107．5TCID 50/ml的柯萨奇B3（CVB3）病毒液。正常及病毒对照组小鼠均予以生理盐水0．2ml灌胃,激素治疗组小鼠分别在感染病毒后不同时期给予泼尼松1mg／kg,灌胃给药10d。采用膜联蛋白V（Annexin V）联合碘化丙啶（PI）染色双参数技术,通过流式细胞术定量检测各组小鼠外周血、胸腺、脾脏淋巴细胞的凋亡,应用流式细胞仪自动细胞记数法测定外周血及脾脏T淋巴细胞亚群CD^3＋、CD^4＋、CD^8＋。采用酶联免疫吸附试验（ELISA）检测抗心磷脂抗体（ACA）。结果：正常小鼠外周血、胸腺、脾脏有少量淋巴细胞凋亡,短期服用激素不增加淋巴细胞凋亡率;病毒性心肌炎小鼠淋巴细胞凋亡增多,应用激素治疗可诱导活化淋巴细胞凋亡．减少其对心肌细胞的浸润。与应用激素治疗的心肌炎小鼠相比,病毒性心肌炎小鼠外周血CD^3＋、CD^4＋、CD^8＋下降差异无显著性。正常小鼠抗心磷脂抗体阳性率较低,病毒性心肌炎小鼠ACA阳性率增加,早期及中期应用激素可降低ACA阳性率。结论：应用激素治疗病毒性心肌炎对细胞免疫功能无严重不良影响,并可明显抑制细胞毒T淋巴细胞对心肌的损害作用．降低自身免疫应答.