日本大耳白兔自发子宫内膜癌1例病理组织学及超微结构观察

本例日本大耳白兔自发子宫内膜癌属腺癌。光镜下癌细胞排列呈腺管状 ,腺腔大小不等 ,胞质少 ,核大 ,癌细胞已侵袭至肌层。电镜下癌细胞呈长椭圆形及不规则形 ,线粒体、粗面内质网较少或无 ,且二者均发生肿胀 ;某些细胞内可见少量初级溶酶体 ;细胞核大且大小不一 ,核膜多凹陷 ;核仁呈网眼状。     

昆明鼠气道致敏模型的建立

目的 建立昆明鼠气道致敏模型。方法 对昆明鼠(实验、对照组各10只)进行了卵清蛋白喷雾致敏,检测了肺组胺浓度,淋巴细胞在体外对OVA的特异性转化,体外抗体生成。并对肺组织作病理学检查。结果 发现上述各项指标实验组较对照组均有明显差异。结论 可以初步肯定通过该致敏途径建立的模型成立。     

Executionary pathway for apoptosis：lessons from mutant mice

Apoptosis or programmed cell death(PCD) is an evolutionarily conserved cellular process that is essential for normal development and homeostasis of multicellular organisms.Defects in the apoptosis signaling result in many diseases including autoimmune diseases and cancer.The apoptosis signaling pathway was first described genetically in the nematode Caenorhabditis elegans which serves as a framework for the more complex apoptotic pathways that exist in mammals.In this review,we will discuss the apoptotic pathways that are emerging in mammals as elucidated by studies of gene-targeted mutant mice.     

鼠巨细胞病毒感染裸鼠肝脏损伤模型的建立

摘要 目的：建立鼠巨细胞病毒（MCMV）感染BALB/c裸鼠肝脏损伤的模型。方法：健康SPF级BALB/c裸鼠10只随机分为实验组和对照组,每组5只。实验组小鼠每只经腹腔注射接种250 μL MCMV 病毒悬液,对照组小鼠每只腹腔接种250 μL DMEM 培养液,于接种后第7天处死,无菌分离其肝脏,通过测定肝组织谷丙转氨酶（ALT）、实时荧光定量PCR检测MCMV DNA拷贝数、苏木精-伊红（HE）染色等方法,观察裸鼠肝脏组织的受损情况。结果：所有实验组的裸鼠均出现了不同程度的腹水;实验组裸鼠测定的肝组织ALT值较对照组明显上升（P<0.05）;实时荧光定量PCR检测出实验组裸鼠肝脏MCMV DNA呈阳性;实验组肝脏病理切片HE染色可见大量炎症细胞浸润,肝细胞嗜酸性变,可见不规则包涵体,而对照组正常。结论：经腹腔注射250 μL MCMV病毒悬液7天后成功构建了裸鼠肝脏损伤的模型,为探究人巨细胞病毒（HCMV）的发病机制以及抗病毒新药和疫苗的研发提供了有利条件。     

大鼠孕期染镉对胎鼠心脏毒性作用的初步研究

目的:探讨SD大鼠孕期染镉,对胎鼠发育及心脏发生的毒性作用。方法:24只健康SD孕鼠随机分为对照组、低剂量组、中剂量组、高剂量组。在孕期第7、10、13天,对照组腹腔注射等量生理盐水,其余三组腹腔注射不同浓度的氯化镉(CdCl2)溶液。怀孕第21d观察胎鼠死胎率、心脏畸形情况;生物化学方法检测胎鼠心脏组织LDH酶活性及总蛋白含量;酶组织化学及免疫组织化学结合图像分析技术检测LDH活性的变化。结果:①高剂量组死胎率比对照组高,差异显著(P<0.01),低、中剂量组与对照组死胎率无差异(P>0.05)。活胎鼠及死胎鼠心脏,肉眼下均未见明显外观和内部分隔畸形。②中剂量组和高剂量组胎鼠心脏LDH活性比对照组显著升高(P<0.01)。③中剂量组、高剂量组胎鼠心脏总蛋白含量明显减少,与对照组差异明显(P<0.01)。结论:①孕鼠氯化镉摄入量达到一定阈值时可明显导致胚胎死亡,具有胚胎毒性,但肉眼下胎鼠心脏无明显的畸形。②氯化镉能增加胎鼠心脏LDH的活性,并存在剂量依从性。③氯化镉能抑制胎鼠心脏总蛋白的生成,对胎鼠具有心脏毒性作用。     

A transient three-plasmid expression system for the production of hepatocytes targeting retroviral vectors

Targeting of retroviral vectors to specific cells was attempted through modifying the surface protein of the murine leukemia viruses （MLVs）, but in many cases the protein function was affected, and it is difficult to achieve the targeted delivery. In this study, we have tried to engineer ecotropic Moloney murine leukemia viruses （MoMLV）-based retroviral vectors to transduce hepatocytes. A chimeric envelope （Env） expression plasmid was constructed containing the hepatitis B virus PreS2 peptide fused to aa ＋1 at the Nterminus of Env. Following simultaneous transfection of pgag-pol, pLEGFP and chimeric env plasmids into 293T cells, helper-free retrovirus stocks with the titer of approximately 104 infectious units/ml were achieved at 48 h post-transfection. These pseudotype vectors showed the normal host range of retrovirus, infecting host NIH 3T3 cells, although the efficiency was reduced compared with that of virions carrying wild-type ecotropic MoMLV envelope. In addition, the resultant pseudotype viruses could transduce human hepatoma cells mediated by polymerized human serum albumin with relatively high titers in comparison with those transductions without polymerized human serum albumin. This approach can be used to target hepatocytes selectively.     

Tetracycline-inducible Expression Systems： New Strategies and Practices in the Transgenic Mouse Modeling

To accurately analyze the function of transgene(s)of interest in transgenic mice,and togenerate credible transgenic animal models for multifarious human diseases to precisely mimic human dis-ease states,it is critical to tightly regulate gene expression in the animals in a conditional manner.The abilityto turn gene expression on or off in the restricted cells or tissues at specific time permits unprecedentedflexibility in dissecting gene functions in health and disease.Pioneering studies in conditional transgene ex-pression have brought about the development of a wide variety of controlled gene expression systems,whichmeet this criterion.Among them,the tetracycline-controlled expression systems(e.g.Tet-off system andTet-on system)have been used extensively in vitro and in vivo.In recent years,some strategies derived fromtetracycline-inducible system alone,as well as the combined use of Tet-based systems and Cre/lox P switch-ing gene expression system,have been newly developed to allow more flexibility for exploring gene functionsin health and disease,and produce credible transgenic animal models for various human diseases.In thisreview these newly developed strategies are discussed.     

短双歧杆菌对鼠伤寒沙门氏菌的抑制

【背景】鼠伤寒沙门氏菌是主要的肠道病原菌之一,利用益生菌治疗肠道病原菌感染已成为一种新型、绿色的微生态疗法。【目的】研究筛选出的短双歧杆菌无细胞发酵上清液(Cell-free supernatant,CFS)对鼠伤寒沙门氏菌的体外抑制作用及机制。【方法】采用微量稀释法测定短双歧杆菌YH68 CFS对鼠伤寒沙门氏菌的最小抑菌浓度(Minimum inhibitory concentration,MIC)和亚抑制浓度(Sub-inhibitory concentrations,SIC),并从鼠伤寒沙门氏菌的细胞形态、细胞膜通透性、膜完整性以及毒力基因表达的变化探讨YH68 CFS对鼠伤寒沙门氏菌的抑菌机理,同时检测YH68 CFS对鼠伤寒沙门氏菌粘附和侵袭肠上皮细胞HT29的影响。【结果】YH68 CFS (3×109 CFU/mL)对鼠伤寒沙门氏菌具有较好的抑制效果,抑菌圈直径为22.27±0.44 mm,最小抑菌浓度为250μL/mL,对鼠伤寒沙门氏菌的抑制机制是通过增加其细胞膜通透性破坏其完整性,形成难以修复的孔洞,最终达到抑菌的目的;亚抑制浓度为62.5μL/mL时YH68 CFS并不能影响鼠伤寒沙门氏菌的生长,但仍然能通过下调毒力基因表达的方式抑制其对肠上皮细胞的粘附和入侵。【结论】短双歧杆菌YH68对鼠伤寒沙门氏菌具有良好的抑菌作用,可作为治疗沙门氏菌感染的潜在益生菌。     

Microdystrophin基因重组腺病毒的构建及转染mdx骨髓间充质干细胞的表达

构建含有人microdystrophin基因的重组腺病毒,来感染dystrophin基因敲除小鼠mdx的骨髓间充质干细胞(ＭＳＣ)进行基因修饰,为同种异体基因修饰的干细胞移植治疗ＤＭＤ疾病奠定基础。用NotⅠ酶切含microdystrophin基因的pBSK-MICRO质粒,获得microdystrophin基因。片段回收后定向插入腺病毒穿梭质粒pShuttle-CMV,获得重组质粒pShuttle-CMV-MICRO。PmeⅠ线性化重组质粒pShuttle-CMV-MICRO,去磷酸化后回收后与腺病毒骨架质粒pAdeasy-1共电转化BJ5183感受态细胞。同源重组后用选择性培养基筛选阳性克隆,提取质粒,用脂质体介导转染293细胞,通过观察293细胞病变及PCR扩增目的基因等方法鉴定重组的腺病毒。然后将病毒上清转染DMD模型鼠mdx小鼠的骨髓间充质干细胞,通过RT-PCR以及间接免疫荧光检测microdystrophin的转录及蛋白表达。成功构建了含有microdystrophin基因的重组腺病毒,病毒滴度为5.58×10¹²vp/mL。间接免疫荧光检测可见microdystrophin蛋白在mdx小鼠MSCs中高效表达。该重组腺病毒载体的构建及成功转染到mdx MSCs内表达为下一步用microdystrophin基因修饰的mdx MSCs进行同种异体移植治疗ＤＭＤ疾病奠定了基础。     

印度假吸血蝠捕食鼠耳蝠

2004年12月10日,在广西南宁地区马山县金伦洞捕到2只雄性印度假吸血蝠(Megaderma lyra:Megadermatidae,Chiroptera),分析其中的胃容物,发现有蝙蝠的残遗物,包括牙齿、后足、骨骼、毛发(棕黄色);未发现昆虫残遗物。通过对残遗物中牙齿(上颌齿式:2.1.3.3)的鉴定,与蝙蝠科鼠耳蝠属(Myotis)的齿式一致,因此确定印度假吸血蝠捕食了鼠耳蝠属的蝙蝠。