Abstract:Objective Atherosclerosis has been linked to inappropriate vascular remodeling,which may result from the accumulation of inflammatory cells and the abnormal metabolism of extracellular matrix.It is presently unknown whether matrix metalloproteinases(MMPs) participate in the early pathological process.The aim of this study was to investigate whether MMPs are involved in atherogenesis in a cholesterol-fed rabbit model. Methods Forty-six New Zealand white rabbits were fed a diet containing 2% cholesterol and 3% lard.The rabbits were euthanized on day 0,and 8 after every 2 weeks to the end of 10th week.Aortic arch was excised and subjected to histological examination,immunohistochemistry and in situ zymography for MMPs and tissue inhibitor of matrix metalloproteinases(TIMPs).Atherosclerotic classification was according to AHA criteria.Results Based on HE staining,Sudan IV staining and macrophage immunostaining,the aortic arches were classified into five: normal artery(n8),initial lesion(n9),fatty streak (n8),preatheroma(n14) and atheroma(n7).During the progression of atherosclerosis,immunostained aortic slices showed that the triad membrane type 1-MMP(MT1-MMP),TIMP-2 and MMP-2,were colocalized with MMP-3 and TIMP-3,and increased in the hyperplastic intima concomitantly with elevated activities of gelatinolysis,caseinolysis,and migration of macrophages and smooth muscle cells.Conclusion During the early stages of atherogenesis,the modulation of MMPs is in a tendency towards activation,while collagen synthesis exceeds its degradation,which may contribute to the migration of macrophages and smooth muscle cells.

Abstract:目的通过研究脂蛋白a对巨噬细胞源性基质金属蛋白酶（MMPs）和基质金属蛋白酶内源性组织拟制剂（TIMPs）表达的调节作用，探讨脂蛋白a促动脉粥样硬化的机制。方法利用从新鲜混合血浆经超速离心和亲和层析纯化的脂蛋白a刺激人单核细胞白血病THp01细胞经豆蔻酰佛波醇乙酯诱导24h转化而成的巨噬细胞。孵育10h和36h后收集细胞裂解液和条件培养基分别进行MMPs／TIMPs mRNA和蛋白检测及明胶酶谱分析MMPs活性。结果免疫印迹结果显示脂蛋白a可使巨噬细胞培养基中MMP-1、MMP-2、MMp09、MT1-MMP水平明显上调．其中MMP-2和MT1-MMP的活性形式明显增加；而其抑制剂TIMP-1、TIMP-2水平则明显减少，以前者的剂量效应最为明显。明胶酶谱分析表明条件培养基中MMP-9活性增强。逆转录聚合酶链式反应结果显示，MMP-1、MMP-2、MMP-9mRNA水平随Lp（a）刺激增强而增加，TIMP-1 mRNA水平则梯度降低，而MT1-MMP、TIMP-2的mRNA水平未见明显改变。结论研究发现Lp（a）可促进巨噬细胞表达多种MMPs，同时抑制TIMPs的表达，由此所致的MMPs／TIMPs表达及活性失衡最终可致基质过度降解，在整体情况下则可能促进斑块进展成不稳定斑块并破裂。为阐明Lp（a）的促动脉粥样硬化机制提供了新的线索。

Abstract:目的通过比较15_羟基二十碳四烯酸(15_HETE)及其两种代谢产物15_酮基二十碳四烯酸(15_KETE)、8(S),15(S)_二羟基二十碳四烯酸[8(S),15(S)_diHETE]对缺氧组与正常组大鼠的肺动脉环张力的影响,以探讨15_HETE的两种代谢产物在缺氧性肺动脉高压形成中的作用。方法16只健康SD大鼠,体重为(220±20)g,随机分为两组(n=8),一组置于正常的培养箱中,其吸入氧(FiO2)浓度为21%,作为正常组;一组置于缺氧的培养箱中,吸入氧(FiO2)浓度为10%,作为缺氧组。9 d后将两组大鼠处死,采用组织浴槽血管环法观察15_HETE、15_KETE、8(S),15(S)_diHETE对正常组和缺氧组大鼠肺动脉环收缩的影响。结果(1)在正常组和缺氧组,15_HETE、15_KETE、8(S),15(S)_diHETE都以浓度依赖方式使大鼠肺动脉环张力增加;(2)15_HETE、15_KETE使缺氧组大鼠肺动脉环张力较正常组显著增高,而8(S),15(S)_diHETE使正常组和缺氧大鼠肺动脉环张力无明显差异;(3)正常组大鼠肺动脉环对15_KETE、8(S),15(S)_diHETE反应力显著高于15_HETE,而缺氧组大鼠肺动脉环对15_KETE反应力显著高于15_HETE、8(S),15(S)_diHETE。结论15_KETE、8(S),15(S)_diHETE可能在缺氧性肺动脉高压形成中起一定的作用。

Abstract:Objective To explore the effect of exogeneous NGF on the expression of ChAT-IR and SP in the central nervous system of demential senile mice.Method Morris water labyrinth was adopted to test the spatial learning and memory function of mice.Immunohistochemical technique was used to observe the expression of ChaT-IR and SP in dementialy senile mice before and after NGF administration.Result The exogeneous NGF improved the spatial learning and memory function of senile mice and expression of ChAT-IR in related area in the brain.SP expression significantly increased in comparison with that before administration(P<0.01).Conclusion Exogeneous NGF can improve the intelligence of aged mice and significantly increase the expression of ChAT-IR and SP in related area in the brain.The exogeneous NGF may exert protective,supportive and repairing effects on neurons.

Abstract:目的探讨不同机械通气模式对肺组织产生肿瘤坏死因子-α、白介素-1β、白介素-6的影响。方法应用家兔油酸型急性呼吸窘迫综合征模型比较不同机械通气时，支气管肺泡灌洗液中肿瘤坏死因子-α、白介素-1β、白介素-6的变化。结果常规通气肿瘤坏死因子-α、白介素-1β、白介素-6水平明显升高，应用肺保护性通气与常规通气比较，指标明显好转，单纯俯卧位通气虽有所好转但差异不明显。结论肺保护性通气不仅可以改善氧合，同时抑制肿瘤坏死因子-α、白介素-1β、白介素-6的释放，减少肺进一步损伤。

Abstract:Objective To establish a nested polymerase chain reaction(Nested-PCR) assay for rapid detection of Campylobacter jejuni(C.jejuni) in laboratory animals.Method Two pairs of primers were designed according to the flaA gene of C.jejuni.DNA was extracted from C.jejuni.The specific amplified fragment of flaA gene which encoding flagellin A protein of C.jejuni was cloned into the pGEM-T vector and transformed E.coli DH5.The recombinant plasmid was identified by restriction endonuclease analysis,and confirmed by sequencing.Non-C.jejuni and 121 clinical specimens were submitted to detect C.jejuni by nested-PCR.Results C.jejuni PCR amplification product of the external primer was 1 719 bp,and nested-PCR amplification product of the internal primer was 640 bp.The sensitivity of nested-PCR was 10 CFU.The whole detection could be finished within 8 h.Non-C.jejuni did not show specific amplified fragment.121 clinical samples taken randomly from laboratory animals were submitted for detection by nested-PCR and bacteria separation method,with a positive detection rate of 25.6%(31/121) and an agreement of 100%.Conclusion These data demonstrated that the nested-PCR assay established here is a specific and sensitive method for rapid detection of C.jejuni in laboratory animals.

Abstract:目的复制慢性复发性实验性变态反应性脑脊髓炎(CrEAE)的动物模型。方法采用豚鼠脊髓匀浆及完全福氏佐剂,对6周龄雌性Hartley豚鼠颈后皮内一次性致敏,对照采用用生理盐水代替脊髓匀浆。致敏后每日进行致残程度评分,并称取体重。结果模型组100%的动物发病,83.3%的动物在2月内有复发,2月内平均发病次数为2.0±0.63次。对照组无一发病。结论本研究成功地复制了CrEAE豚鼠模型,是目前较好的多发性硬化动物模型。

Abstract:Objective To establish a vascular dementia model in rats. Methods To establish a vascular dementia model by repeatedly clipping the common carotid artery and bloodletting from the rat tail, and to evaluate the model by testing the animal behavior and measurement of the acetylcholine content in hippocampus of the rats. Results The created rat vascular dementia model showed significant alteration in leaning and memory function, and obvious decreased content of acetylcholine in hippocampal tissues. Conclusion A rat model of vascular dementia has been successfully established. This rat model is useful for vascular dementia research and can be used in experimental studies, drug screening and evaluation of therapeutic effectiveness.

Abstract:Objective To investigate the factors affecting cryopreservation of mouse sperm.Methods Mice sperm from C57BL/6J,FVB/NJ,B6D2F1 and ICR strains were cryopreserved using 18% raffinose,3% skim milk as cryoprotectant solution,and estimated the survival and fertility of post-thawed sperm from the five strains.The progressive motility of sperms from each strain was affected differently.Results The fertility rate of C57BL/6J,FVB/NJ,B6D2F1,KM and ICR strains were significantly decreased from 81.4%,87.2%,90.4%,82.7% and 79.4%,respectively,of fresh sperm,to 6.7%, 46.0%,76.8%,59.2% and 31.9%,respectively,when using post-thawed sperms(P<0.01).Conclusion The fertility and susceptibility to cryopreservation of sperm from mice of different genetic background differ significantly.

Abstract:Objective To study the relationship between lymph node metastasis and prognosis and the p53 gene mutation and expression of p53 protein in carcinoma and paracancerous tissues of the stomach.Methods The mutation of p53 gene and expression of p53 protein were examined by PCR-SSCP and immunohistochemical staining techniques.Results(1) The positive expression rate of p53 protein was 47.6% and 38.1% in carcinomas and paracanerous tissues,respectively.The expression of p53 protein reached to 52.8%.(2) The mutation rate of the exon 7 was 23.9% and 19.0% in paraffin-embedded carcinomas and paracancerous tissues,respectively.The mutation rate of exon 6 was 10.5% and 8.6% in paraffin-embedded carcinomas and paracancerous tissues,respectively.The mutation rate of exon 8,9 was 1.9% and 1.0% in paraffin-embedded carcinomas and paracancerous tissues,respectively.Conclusion In cases with lymph node metastasis,the mutation of p53 gene and expression of p53 protein was apparently increased,indicating that the mutation of exons in the development and progression of gastric carcinoma is an important factor.It also facilitates the metastasis of tumor.The mutation of p53 gene and high expression of p53 protein are not significantly different in carcinomas and paracancerous tissues of the stomach.

Abstract:Objective In order to make a foundation for molecular diagnosis and gene engineering studies of Avian encephalomyelitis virus(AEV),the structural protein VP3 gene of AEV and expression of its recombinant protein were cloned and sequenced.Methods We designed a pair of primers to amplify the van-Roekel VP3 gene from AEV infected SPF embryo with specific RT-PCR technique.The amplified product was cloned into PDM18-T vector after purification and withdraw.The VP3 gene was sub-cloned into the eucaryotic expression donor plasmid pFastHTa,which was also digested by EcoR I and Xho I.The recombinant plasmid was transfected into E.coli.DH10Bac competence cells.Then selected by PCR and identified by EcoR I and Xho I degistion,and transposition happened.The transpositional recombinant bacmid was transfected into Sf9 insect cells,and then a kind of recombinant baculovirus was obtained.The antigen activity of the recombinant protein was identified by Western blot.Results The results showed that VP3-c contained 735 bp and 245 amino acids,sharing a 93% and 97% homology with AEV-1143 strain,respectively.It was also compared with other small RNA viruses,and recombinant protein was also achieved by Western-blot.The recombinant protein was about 27 ku.Conclusion Using RT-PCR technique,the van-Roekel VP3 gene has been for first time amplified in vitro.It has been also cloned and sequenced.Using Bac-to-Bac expression system,the recombinant protein has been achieved and proven to exhibit high immune activity.

Abstract:目的测定3月龄SPF级和普通级新西兰兔的主要脏器系数，并进行对比研究。方法选用3月龄SPF级和普通级新西兰兔各30只（♂15只，♀15只），用电子天平分别测定心、肝、脾、肺、肾、肾上腺、胃、睾丸、附睾和子宫的脏器系数。结果（1）SPF级新西兰兔的主要脏器系数与普通级新西兰兔的相比，除了肾上腺的脏器系数二者之间差异不显著之外（P〉0．05），前者其余主要脏器的脏器系数均显著低于后者（P〈0．01）；（2）SPF级新西兰雄兔除了肝、脾、肾的脏器系数显著高于雌兔之外（P〈0．01），雄兔其余脏器的脏器系数与雌兔相比差异均不存在显著性（P〉0．05）。结论不同环境条件和饲养管理对SPF级和普通级新西兰兔主要脏器系数有一定影响。

Abstract:目的说明小鼠灌胃给药测定LD50的结果存在歧义性。方法LD50测定某生物碱采用简化几率法。数据统计采用t检验及对比限法。结果ICR小鼠(两种性别)灌胃给药的LD50为197.56±15.07 mg/kg。分性别单独计算LD50时,由于各自出现两个全部死亡(死亡率为100%)剂量组。分别取各自的数据计算均可得到:雌性小鼠LD50为226.67±18.26 mg/kg(方法一)或201.88±13.49 mg/kg(方法二),两者相比P<0.05;雄性小鼠LD50为179.38±20.09 mg/kg(方法一)或169.86±15.92 mg/kg(方法二),两者相比P<0.05。结论以简化几率法小鼠灌胃给药测定样品的LD50存在结果歧义性的可能。

Abstract:Objective To establish a new technique for measurement of intrathoracic pressure in guinea-pigs. Methods When an anaesthetized guinea-pig was fixed on the back, an i.v. catheter was punctured into the thoracic cavity between the fifth and sixth costal bones. Then slowly take out its core and immediately connect its chlamyd with a pressure transducer. At this time, the computer will display the curve of intrathoracic pressure. Results i.v. catheter replacing the endothoracic catheter can be used to measure the intrathoracic pressure in guinea-pigs. Conclusion It has been shown that this method is simple and practical, hardly leading to injury to the pulmonary lobes in anlmals.

Abstract:Objective To evaluate the disinfection effects of acetic peroxide and 84-disinfectant on individually ventilated cages(IVC).Methods IVC cages were soaked with acetic peroxide or disinfectant-84 for corespondingly fixed time and concentration.The total bacteria and air borne bacteria(koch) in IVC cages were determined.Results and Conclusion IVC cages can be disinfected by both 0.2%,0.5%,1.0%,2.0% acetic peroxide and disinfectant-84,respectively,for 5 minutes.To be safe,we soaked IVC cages with 0.5% acetic peroxide or disinfectant-84,for 10 minutes,alternatively.The effect is excellent.No pollution has been observed for more than one year.SPF is obtained for nude mice kept in such disinfected IVC cages.

Abstract:目的探讨建立大鼠原位肝移植模型的方法与技术。方法用改进的二袖套法行100例Lewis→BN大鼠原位肝移植,术中门静脉、肝下下腔静脉用袖套法吻合,肝上下腔静脉用缝合法吻合,胆管内支架法完成胆道重建。结果供体手术时间(30.9±5.0)min,供肝修整时间(10.0±3.0)min,受体手术时间(50.0±5.5)min,无肝期为(23.0±2.5)min。手术成功率为92%(术后存活2 d以上),1周存活率为87%,1个月存活率为84%。结论通过提高手术技巧,熟悉各种并发症的原因和预防处理措施,可以减少并发症的发生,提高手术成功率,延长大鼠术后存活时间。

Abstract:Objective A vaccine with good immunogenicity, high safety and ideal effectiveness is crucial for vaccination against HIV. Scientists in China have also developed various vaccines, but still need to be further tested. In this review, the techniques and strategies related to preventive and therapeutic vaccines are summarized and introduced to readers.

Abstract:Objective The Vitamin E(VE) is a necessary liposoluble vitamin for animals,performing an important physiological function in animal body,and exert significant effects on development of many biological characteristics in animals.This review summarized in detail various nutritional function of VE,described briefly the factors influencing VE stability,and according to the author's own experience,put forward how many amount of VE should be given in the laboratory full nutritional value cooperated pelletized feed for rats.

Abstract:Sterol regulatory element binding proteins(SREBPs) are membrane-bound transcription factors that activate genes encoding enzymes of cholesterol and fatty acid biosynthesis.SREBPs are synthesized as precursor proteins in the endoplasmic reticulum(ER),where they form a complex with another protein,SREBP cleavage activating protein(SCAP).SCAP escorts SREBP to activation in the Golgi apparatus.There,SREBP undergoes two proteolytic cleavage steps to release the mature,biologically active transcription factor,nuclear SREBP(nSREBP).The process is induced by two proteins,SCAP and Insig.This review is to summarize the role of SCAP and Insig in the procession and maturation of SREBP and the lipid metabolism.

Abstract:Primary hepatocellar carcinoma is one of frequent malignant tumors, which is related to Hepatitis B virus infection. Occurrence of liver carcinoma is a synergistic action by multiple factors which include virus infection, carcinogen, oncogene activation, anti-oncogene inactivation, liver cell apoptosis, failure of proliferation regulation and so on.

Abstract:Embryonic stem cells(ESC) are undifferentiated totipotent cells that could be differentiated in vivo into any kind of cells theoretically,including germ cells.The germ cells undergoing meiosis that could influence the genetics of progeny ultimately,so successes of the differentiation from ES into germ cells in vitro means great leap not only of significance in development technically but also be a challenge to science interfering with traditional ethic conception.The present work is going to summarize the current research literatures on this topic.

Abstract:Laboratory animal sciences in our country haave entered into a fast developing period. It is of great importance to bring up a team of laboratory animal staff with high professional diathesis and specialized skills. Until now the training and education of laboratory animal workers is also an important means for improving staff diathesis, enhancing professional knowledge and technology, carrying out policy and impelling the standard process of laboratory animals. The aim of this work is to review the progress and analyze the present content and characteristics in training of laboratory animal personnels.