锌对小鼠组织金属硫蛋白表达的影响

目的：探讨锌（Zn）对小鼠各脏器金属硫蛋白（MT）含量的影响。方法：采用[¹⁰⁹Cd]-hem饱和法测定组织MT蛋白含量。结果：10mg Zn/kg腹腔注射后8-48 h小鼠肝脏及脾脏MT含量明显高于对照组（P<0.05, P<0.01）注射后24 h，MT含量达峰值；2.5-10 mg Zn/kg注射后16 h肝脏MT含量或5-10 mg Zn/kg注射后16 h脾脏MT含量均显著高于对照组（P<0.01）。但注Zn后脑及胸腺MT含量无明显差异。结论：Zn能迅速诱导小鼠肝脏及脾脏MT蛋白合成，并呈明显的剂量依赖性增加；Zn诱导小鼠组织MT合成具有明显的组织器官特异性。     

Freshly isolated mouse 4F7+ splenic dendritic cells process and present exogenous antigens to T cells

The antibody 4F7 was reported to recognize an epitope expressed on dendritic cells (DC) from various tissues. To study the ability of splenic 4F7⁺ dendritic cells to process antigen for presentation to CD4⁺ T cells, DC were enriched using a separation procedure avoiding overnight culture which could lead to an altered phenotype. These DC were used as antigen-presenting cells (APC) in stimulation cultures of major histocompatibility complex class II-restricted T cells. It was found that they induce antigen-dependent lymphokine production by T cells and therefore could present exogenous antigens. These processing takes place intracellularly, because fixation abrogates presentation to T cells. Moreover, antigen presentation needs intracellular processing within endo- or lysosomes as chloroquine-treatment prevents T cell activation. Titration of APC numbers revealed that contaminating APC most likely did not account for antigen-specific T cell activation by DC. No evidence was found for release of antigenic peptides or for partial antigen processing possibly done by cell surface located enzymes on DC. In conclusion, these results indicate that freshly enriched DC are able to process antigens similarly to other APC.     

右旋柠烯抑制小鼠S-180移植瘤生长的实验观察

目的观察右旋柠烯乳剂(D-limonene)对小鼠移植瘤生长及转移的抑制作用。方法用小鼠S180癌性腹水建立皮下移植瘤模型,随机分为3组,预防组建模当天开始给药;治疗组移植后第5天开始给药;对照组不给药。每3d测量肿瘤大小,20d后取材,观察肿瘤细胞的浸润程度及淋巴结转移。结果对照组肿瘤体积较大,与皮肤及深部组织发生粘连,7只发现颈部或腋下淋巴结肿大。治疗组和预防组移植瘤生长速度明显缓慢,体积小,且瘤体较规则,未发现有淋巴结转移者。结论右旋柠烯有抑制肿瘤生长,减少淋巴结转移的作用,其机制有待进一步探讨。     

小鼠气道反应性的测定

目的:测量各种小鼠呼吸模型的肺功能，尤其是非离体的动态肺功能，对于呼吸疾病的研究具有重要意义。 方法:主要包括整体测量方法和离体测量方法。而整体法又主要分为有创法（主要为气道阻力、顺应性的测定）和无创法（Penh，enhanced pause的测定）。本篇主要介绍整体的测量方法。 结论:不同的方法各有利弊，适用于不同的实验要求。     

白藜芦醇诱导人胃癌原代细胞裸鼠移植瘤凋亡的研究

目的：探讨白藜芦醇诱导人胃癌原代细胞裸鼠移植瘤凋亡的机制。 方法： 建立人胃癌原代细胞裸鼠移植瘤模型，采用瘤旁注射的方法，用不同剂量的白藜芦醇进行治疗，并设对照，用透射电镜和TUNEL法检测肿瘤组织细胞凋亡情况，免疫组织化学法和RT-PCR法检测肿瘤组织的凋亡相关基因bcl-2和bax的表达情况。 结果： 白藜芦醇对胃癌原代细胞移植瘤有明显的抑制作用； 透射电镜和TUNEL法发现白藜芦醇导致移植瘤内大量细胞发生凋亡；免疫组织化学法发现白藜芦醇注射组的Bcl-2蛋白阳性细胞率（3.92％±0.85％、5.70％±0.84％和11.86％±0.97％）明显低于两个对照组（P<0.05），两个对照组（27.56％±1.40％和29.48％±0.51％）之间无显著差异；Bax蛋白阳性细胞率（52.30％±1.54％、45.72％±0.88％和40.02％±1.20％）明显高于两个对照组（P<0.05），两个对照组（20.88％±0.91％和19.34％±0.35％）之间无显著差异； RT-PCR法发现白藜芦醇注射组的bcl-2 mRNA条带强度随剂量的增大而递减，并明显低于两个对照组（P<0.05），两个对照组之间无显著差异（P>0.05）；bax mRNA条带强度递增，并明显高于两个对照组（P<0.05），两个对照组之间无显著差异（P>0.05）。 结论： 白藜芦醇对胃癌原代细胞移植瘤有明显的抑制作用，通过下调bcl-2 的表达和上调bax 的表达而诱导胃癌裸鼠移植瘤细胞发生凋亡，是其抗胃癌作用的机制之一。     

环孢菌素A抑制小鼠同种心脏移植急性排斥反应中Lymphotactin表达的研究

目的：研究小鼠同种心脏移植急性排斥反应中淋巴细胞趋化因子（lptn）的表达情况及环孢菌素A（cyclosporine A, CsA）的抑制作用。 方法： 改良Banff评分系统判断同种小鼠移植心急性排斥反应程度，RT-PCR检测移植心组织内淋巴细胞趋化因子表达水平，ELISA方法检测心脏移植小鼠脾细胞活化T细胞核因子(NFAT)活性。 结果： C57BL/6-Balb/c急性排斥组小鼠移植术3 d后脾脏显著增大。术后第5、7 d移植心肌间淋巴细胞浸润程度评分分别为2.667±0.577和2.333±0.577。C57BL/6-Balb/c+CsA组小鼠移植术后脾脏肿大明显减轻，术后第5、7 d心肌间淋巴细胞浸润程度评分分别为1.000±0.000和1.333±0.577。急性排斥组和CsA处理组小鼠移植心脏在术后第5 d和第7 d都可检测到Lptn mRNA阳性表达，但CsA处理组Lptn mRNA的表达明显弱于急性排斥组。治疗剂量的CsA可以完全抑制NFATc1活性。 结论： Lptn在早期移植免疫事件中具有重要的作用，CsA仅能部分抑制Lptn mRNA的表达。活化T细胞Lptn的表达调控存在NFAT以外的途径。     

雌激素处理DCs在诱导小鼠同种皮肤移植免疫耐受中的作用

目的：研究雌二醇（17β-estradiol, E₂）处理的供体骨髓来源树突细胞（dendritic cells, DCs）在诱导小鼠同种异基因皮肤移植免疫耐受中的作用。方法：体外培养小鼠骨髓来源DCs，然后用E₂处理。受体小鼠在皮肤移植前经尾静脉分别输注经E₂处理的供体小鼠DCs、供体小鼠成熟DCs以及不成熟DCs，输注PBS为对照组。1周后对受体小鼠进行同种异基因皮肤移植，手术后观察皮肤存活情况，应用流式细胞术检测手术前后受体小鼠外周血中CD4+CD25+调节性T细胞百分率的变化。结果：在同种异基因皮肤移植中，受体小鼠尾静脉输注经E2处理的DCs组与对照组和不成熟DCs组比较，移植皮肤存活时间显著延长，较不成熟DCs组存活时间平均延长10.6 d（P<0.01）；与对照组和不成熟DCs组比较，E₂处理组外周血中CD4+CD25+ 调节性T细胞百分率明显升高（P<0.01）。结论：在同种异基因小鼠皮肤移植模型中，E₂处理的供体小鼠DCs可以延长移植皮肤存活时间。     

BHA通过ERK信号转导途径促进小鼠胎肝细胞神经组织细胞特异基因表达的研究

目的：了解丁羟回香醚（BHA）对小鼠胎肝（FL）细胞神经组织特异基因表达的影响及其信号途径。 方法： 采用MACS试剂盒分离小鼠胚胎肝Sca-1+细胞，以DMEM+10%胎牛血清培养液培养；第4 d后，加入或者不加入细胞外信号调节蛋白激酶特异抑制剂PD98059 (25 μmol/L)处理24 h，再加入BHA处理24 h（0.2 mmol/L）。然后在无血清培养基中培养5 d。用Western blotting和半定量RT-PCR方法分析BHA处理前后基因表达。 结果： 经BHA诱导处理后，细胞表达神经组织细胞特异蛋白显著增加如神经丝轻链（NF-L）、神经丝重链（NF-H）、脑因子1（BF-1）和酪氨酸羟化酶（TH）。NF-L、NF-H、BF-1和TH分别增加6.32倍、2.73倍、3.37倍、2.68倍。而PD98059能明显抑制BHA诱导的神经组织细胞特异蛋白NF-L、NF-H、BF-1和TH的表达。 结论： BHA通过细胞外信号调节蛋白激酶途径促进小鼠FL Sca-1+细胞表达神经组织细胞特异抗原、结构和功能基因。     

Horizontal optokinetic ocular nystagmus in wildtype (B6CBA+/+) and weaver mutant mice

Summary Horizontal optokinetic nystagmus (OKN) evoked by a random dot pattern moving at a constant speed around the animal was investigated in wild-type mice and Weaver mutants (cerebellar impairment) by means of chronically implanted EOG-electrodes. The shape of OKN in the homozygotic Weaver mouse was clearly different from that in normal mice. The OKN in the mutant showed inconstant velocity during the slow phase. Nystagmus frequency of the mutant was significantly below that of normal controls for velocities of 1.4 to 25 degrees · s^-1. In one group of normals the mean slow-phase gain was relatively constant for stimulus angular velocities between 1.4 and 15 degrees · s^-1 and declined thereafter. In a second group the mean slow-phase gam decreased gradually between stimulus angular velocities from 1.4 to 15 degrees · s^-1 and thereafter with a steeper slope. In mutants gain decreases with increasing stimulus velocity over the entire range tested (1.4 to 42 degrees · s^-1). Normals and mutants with one eye occluded exhibited strong OKN when the pattern was moved in a temporonasal direction; little response was obtained by stimuli moving in a naso-temporal direction.     

Intramucosal Helicobacter pylori in the human and murine stomach: its relationship to the inflammatory reaction in human Helicobacter pylori gastritis

Intramucosal Helicobacter pylori (H. pylori) has been described in biopsy tissues and culture systems. However, the association of intramucosal H. pylori with histopathologic features has not been evaluated. The purpose of this study is to investigate the relationship between intramucosal H. pylori and inflammatory reactions in H. pylori infection. In 113 randomly selected human gastric biopsies and 20 murine stomachs, which were inoculated with SSI every day for a week, immunohistochemical analysis for intramucosal H. pylori was done and correlated with histologic parameters. Electron microscopic examination was done on murine stomachs. H. pylori infection was present in 104 gastric biopsies and 17 murine stomachs. Intraepithelial immunopositivity for H. pylori was detected in 27 of 104 (26%) biopsies and in 11 of 17 (65%) murine stomachs. Lamina proprial immunopositivity for H. pylori was present in 51 of 104 (48%) biopsies. Neutrophil-associated immunopositivity for H. pylori was observed in 22 of 90 (24%) biopsies with H. pylori chronic active gastritis. Lamina proprial and neutrophil-associated immunopositivity for H. pylori correlated significantly with the density of H. pylori and the grade of acute inflammatory reaction in H. pylori gastritis. Intramucosal location of H. pylori itself or its antigen is closely associated with acute inflammatory reactions and may play an important role in establishing a persistent infection in chronic H. pylori gastritis. Furthermore, lamina proprial and/or neutrophil-associated H. pylori appears to be more important than intraepithelial H. pylori in acute inflammatory reactions of H. pylori gastritis.