信息化背景下病理动物实验教学改革新思路

病理动物实验是病理教学的重要组成部分,主要利用人为操作在适宜动物身上复制特定的疾病模型,通过这种疾病模型的复制和模拟,学生不但可以锻炼动手能力,还能够更好地理解疾病的发生发展过程。但是在实际教学过程中,由于师资、场地以及经费等多方面因素制约,病理动物实验开展困难重重。本文通过分析现阶段护理职业教育中病理动物实验开展现状,探讨可能存在的问题,探索如何应用信息技术和手段调整教学设计思路,以更好地适应当前护理职业教育需求,提高教学效果和效率。

动物病理学实验教学改革与探索

通过对传统教育方式的改革,提高了学生分析问题、解决问题的能力,培养了多元思维能力和创新意识,学生对学习产生了浓厚的兴趣。

动物病理解剖实验课程创新教育探索与实践

创新精神与能力培养是高等教育承担的基本职责。动物病理解剖实验课程是动物医学类专业的必修基础课程,对动物医学类临床工作具有重要的指导意义。笔者在对国内动物病理学解剖实验课程存在问题进行分析的基础上,结合教学实践活动,在创新教育的方面进行了探索与实践,取得了较好的教学效果。

水产动物病理学实验课的教学问题及探讨

水产动物病理学实验课是水产动物医学新专业中的专业核心课水产动物病理学的配套课程。本课程通过观察动物病理剖检标本和病理组织学切片标本,以求提高病理诊断实际操作能力的一门实验课程。作为上海海洋大学第一届该课的授课老师,本文作者在备课和授课的过程对此课程授课中存在的问题进行思考、归纳和总结,以期为今后该课程及相关课程的开展提供经验,并为进一步改进教学效果提供帮助。

动物病理学实验教学研究与实践

动物病理学是兽医学一门重要的理论与实践学科,是联系基础学科与临床学科的桥梁。该文主要探讨如何在动物病理实验教学中激发、引导、培养学生的创新性思维和实践能力。

动物病理解剖学实验教学新模式实践研究

通过对动物病理解剖学实验教学内容、教学方法、实验操作、实验效果等方面评价进行探索改进,以提高学生学习积极性和实验操作能力为目标,拓展学生自主探究知识及提升科研逻辑的实验思维,使学生更好地掌握动物疾病病因、机制、病理变化,从而能够深层次了解引起病变的本质,为进一步强化动物病理学实验教学改革奠定基础。

动物病理实验室管理与体会

动物病理实验室是进行兽医临床诊断、实验教学和科研的主要实验室,在动物病理实验室的管理中,实行实验室的管理制度,重视危害因素对动物病理检测人员健康的影响,稳定动物病理人员的工作心态,从而保证病理实验顺利开展。

基于《水生动物病理学实验》授课经验浅谈安全意识与培养

结合水生动物病理学实验课授课经验,从实验器材、液体、操作和管理四个方面,分享实验过程中可能存在的安全隐患。在安全中谈收获和进步。

兽医病理学检测领域CNAS认可能力范围表述浅析

现阶段,由于兽医病理学检测认可能力范围表述存在一定差异,中国合格评定国家认可委员会(China National Accreditation Service for Conformity Assessment,CNAS)认可实验室在兽医病理学检测领域扩项申报过程及评审员评审过程中出现了不规范、不统一的情况,使很多从事实验动物病理学检测及科研工作的实验室无法获得相关资质。本文通过对兽医病理学检测领域CNAS认可能力范围表述存在问题进行分析,对比英国、美国、加拿大、新西兰、新加坡等国外实验室兽医病理学能力范围表述,以及CNAS和其他ISO/IEC 17025认可机构的医学病理学实验室检测能力范围表述,并结合我国兽医病理学实验室认可实践情况,提出了针对兽医病理学检测领域能力范围表述的建议,期望进一步统一和规范我国兽医病理学检测领域的认可能力范围表述,以提升我国认可制度的规范性。

Histopathological comparison of topical therapy modalities for acute radiation proctitis in an experimental rat model

AIM： To evaluate the prevalent topical therapeutic modalities available for the treatment of acute radiation proctitis compared to formalin. METHODS： A total of 120 rats were used. Four groups （n = 30） were analyzed with one group for each of the following applied therapy modalities： control, mesalazine, formalin, betamethasone, and misoprostol. A single fraction of 17.5 Gy was delivered to each rat. The rats in control group rats were given saline, and the rats in the other three groups received appropriate enemas twice a day beginning on the first day after the irradiation until the day of euthanasia. On d 5, 10, and 15, ten rats from each group were euthanized and a pathologist who was unaware of treatment assignment examined the rectums using a scoring system. RESULTS： The histopathologic scores for surface epithelium, glands （crypts） and lamina propria stroma of the rectums reached their maximum level on d 10. The control and formalin groups had the highest and mesalazine had the lowest, respectively on d 10. On the 15^th d, mesalazine, betamethasone, and misoprostol had the lowest scores of betamethasone. CONCLUSION： Mesalazine, betamethasone, and misoprostol are the best topical agents for radiation proctitis and formalin has an inflammatory effect and should not be used.

Kinetic method for enzymatic analysis by predicting background with uricase reaction as model

Objective：To investigate the reliability for kinetic assay of substance with background predicted by the integrated method using uricase reaction as model. Methods： Absorbance before uricase action （Δ0） was estimated by extrapolation with given lag time of steady-state reaction. With Km fixed at 12.5μmol/L, background absorbance （Δb） was predicted by nonlinearly fitting integrated Michaelis-Menten equation to Candida utilis uricase reaction curve. Uric acid in reaction solution was determined by the difference （ΔA） between Δ0 and Δb. Results .Ab usually showed deviation 〈3% from direct assay with residual substrate done fifth of initial substrate for analysis. ΔA showed CV 〈5% with resistance to common interferences except xanthine, and it linearly responded to uric acid with slope consistent to the absorptivity of uric acid. The lower limit was 2.0 μmol/L and upper limit reached 30 μmol/L in reaction solution with data monitored within 8 min reaction at 0. 015 U/ml uricase. Preliminary application to serum and urine gave better precision than the direct equilibrium method without the removal of proteins before analysis. Conclusion .This kinetic method with background predicted by the integrated method was reliable for enzymatic analysis, and it showed resistance to common interferences and enhanced efficiency at much lower cost.

Analysis of the mechanisms of rabbit's brainstem hemorrhage complicated with irritable changes in the alvine mucous membrane

AIM: To explore the dynamic changes in the pressure of the lateral ventricle during acute brainstem hemorrhage and the changes of neural discharge of vagus nerve under the load of intracranial hypertension, so as to analyze their effects on the congestive degree of intestinal mucous membrane and the morphologic changes of intestinal mucous membrane.METHODS: An operation was made to open the skull to obtain an acute brainstem hemorrhage animal model.Microcirculatory microscope photography device and video recording system were used to determine the changes continuously in the caliber of jejunal mesenteric artery during brainstem hemorrhage and the changes with time in the congestion of jejunal mucosal villi. We used HE stain morphology to analyze the changes of duodenal mucosal villi. A recording electrode was used to calculate and measure the electric discharge activities of cervical vagus nerve.RESULTS: (1) We observed that the pressure of lateral cerebral ventricle increased transiently during acute brainstem hemorrhage; (2) The caliber of the jejunal mesenteric artery increased during brainstem hemorrhage.Analysis of red color coordinate values indicated transient increase in the congestion of jejunal mucous membrane during acute brainstem hemorrhage; (3) Through the analysis of the pathologic slice, we found enlarged blood vessels, stagnant blood, and transudatory red blood cells in the duodenal submucous layer; (4) Electric discharge of vagus nerve increased and sporadic hemorrhage spots occurred in duodenal mucous and submucous layer, when the lateral ventricle was under pressure.CONCLUSION: Brainstem hemorrhage could causeintracranial hypertension, which would increase the neural discharge of vagus nerve and cause the transient congestion of jejunal mucous membrane. It could cause hyperemia and diffused hemorrhage in the duodenal submucous layer 48 h after brainstem hemorrhage.

Microcirculation disturbance affects rats with acute severe pancreatitis following lung injury

AIM: To study the effects of microcirculation disturbance(MD) on rats with acute severe pancreatitis (ASP).METHODS: We developed ASP rat models, and anatomized separately after 1, 3, 5, 7, and 9 h. We took out blood and did hemorrheologic examination and erythrocyte osmotic fragility test, checked up the water content, capillary permeability, and genetic expression of intercellular adhesion molecule-1 (ICAM-1) in lung tissues, examined the apoptosis degree of blood vessel endothelium while we tested related gene expression of Bax and Bcl-2in lung tissues. We did the same examination in control group.RESULTS: The viscosity of total blood and plasma, the hematocrit, and the erythrocyte osmotic fragility were all increased. Fibrinogen was decreased. The water content in lung tissues and capillary permeability were increased.Apoptosis degree of blood vessel endothelium was increased too. ICAM-1 genetic expression moved up after1 h and reached its peak value after 9 h.CONCLUSION: MD plays an important role in ASP following acute lung injury (ALI). The functional damage of blood vessel endothelium, the apoptosis of capillary vessel endothelium, WBC edging-concentration and the increasing of erythrocyte fragility are the main reasons of ALI.

CXCL16 participates in pathogenesis of immunological liver injury by regulating T lymphocyte infiltration in liver tissue

AIM： To investigate the role of CXCL16 in the pathogenesis of immunological liver injury and to explore the possible mechanism ofT lymphocyte infiltration regulated by CXCL16. METHODS： Immunological liver injury in murine model was induced by Bacille Calmette-Guerin and lipopolysaccharide. Expression pattern and distribution of CXCL16 were examined by real-time quantitative RT-PCR and immunohistochemical analysis. Anti-CXCL16 antibody was administrated in vivo to investigate its effect on T-cell recruitment and acute hepatic necrosis. The survival of murine model was also evaluated. RESULTS, The murine immunological liver injury model was successfully established, CXCL16 expression increased and predominantly distributed in periportal areas and vascular endothelia in injured liver tissues. Administration of anti-CXCL16 Ab protected the mice from death and acute liver damage. Approximately 70% of the mice survived for 72 h in the anti-CXCL16 Ab treatment group, whereas 80% died within 72 h in control Ab group. The number of liver-infiltrating T lymphocytes was significantly reduced from 1.01×10^7 to 3.52×10^6/liver, compared with control Ab treatment. CONCLUSION： CXCL16 is involved in immunological liver injury by regulating T lymphocyte infiltration in liver tissue.

Comparative study of histopathology changes between the PS1/APP double transgenic mouse model and Aβ_(1-40)-injected rat model of Alzheimer disease

Objective To identify the genetype of the PS1/APP double transgenie mouse model, then to analyse the histopathological changes in the brain and compare the differences between the transgenie mice models and Aβ1-40-injeeted rats models of Alzheimer disease. Methods The modified congo red staining, Nissl＇s staining and immunohistology staining was used to observe the Aβ deposits, activation of astrocyte respectively. Results ①The PS1/APP transgenic mouse extensively displayed Aβ deposits in the cortex and hippocampal structures, and GFAP positive cells were aggregated in mass and surrounded the congo red-positive plaque. ②The Aβ1-40-intrahippocmnpal-injeeted rat model showed the Aβ plaque deposits in the dentate gyrus of the hippocampus, with the astrocyte surrounded. The neurons loss was significant in the injection point and pin hole of injection with Nissl＇s staining methods. GFAP-positive cells increased significantly compared with the uninjected lateral of the hippocampus. Conclusion Although Aβ1-40-injected rat models could simulate some characteristic pathological features of human Alzheimer diseases, Aβ deposits and neurons loss in partial hippocampal, it would not simulate the progressive degenenration in the brain of AD. The double transgenie PS1/APP mice could simulate the specific pathogenesis and progressive changes of AD, mainly is Aβ deposits and the spongiocyte response , while no neurons loss were observed in this model.

Anti-hepatoma effect of arsenic trioxide on experimental liver cancer induced by 2-acetamidofluorene in rats

AIM： To study the anti-hepatoma efficiency of arsenic trioxide （As2O3） in the treatment of experimental rat hepatocellular carcinoma （HCC） induced by 2-acetamidofluorene （2-FAA） and to elucidate the possible mechanisms. METHODS： SD rats （2 mo old） had been fed with 2-FAA for 8 wk to induce HCC, and then they were treated with As2O3 or matrine. On d 29, the rats were killed and the liver was weighed and liver tumors were counted. The histological changes of liver tissue were observed under microscope, and the cellular dynamic parameters were studied by flow cytometry. Immunohistochemistry （two-step method） was used to observe the expression of vascular endothelial growth factor （VEGF） and micro-vessel density （MVD） on consecutive sections. The pathological parameters were also analyzed, the levels of serum aspartate aminotransferase （AST）, alanine aminotransferase （ALT）, total bilirubin （TBi）, and direct bilirubin （DBi）. RESULTS： The number of liver tumors decreased significantly in groups treated with As2O3, especially in medium-dose （1 mg/kg） group （t = 2.80, P〈0.01）. As2O3 caused HCC cell death via apoptosis; necrosis was seen and apoptosis was common when the dose was 1 mg/kg. Proliferation index decreased sharply in medium-dose （1 mg/kg） group （7.87±4.11 vs24.46±6.49, t= 2087, P〈0.01）, but not in 0.2 mg/kg group. However, S-phase fraction decreased dramatically in both groups, it reached the bottom level only when the dose was i mg/kg compared with control （0.40±0.13 vs3.01±0.51, t= 2.97, P〈0.01）, and it was obviously accompanied with accumulation of cells in G0/G1 （G0/G1 restriction）. The expressions of VEGF and MVD in medium-dose （1 mg/kg） group were significantly lower than normal saline group （0.63±0.74 vs2.44±0.88, P〈0.05; 15.75±3.99 vs47.44±13.41, t= 2.80, P〈0.01）. Compared with normal saline group, mediumand low-dose groups As203 and matrine lowered the levels of ALT in serum （61.46±9.46, 63.75±20.40, 61.18±13.00 vs 108.98±29.86, t= 2.14, P〈0.05）, but had no effect onthe level of serum AST, TBi, and DBi. CONCLUSION： As203 had inhibitory effect on growth of experimental HCC in rats induced by 2-FAA, but had no obvious effect on normal hepatic cells. The mechanisms may involve decrease of cell division, accumulation of cells in G0/G1 phase, apoptosis of tumor cells, and inhibitory effect on angiogenesis through blocking VEGF.

Effect of hypercholesterolemia on experimental colonic anastomotic wound healing in rats

AIM： To evaluate the mechanical and biochemical parameters of colonic anastomotic healing in hypercholesterolemic rats. METHODS： Sixty rats were divided into two groups of 30 each according to their dietary regimens. The test group was fed with a high cholesterol-containing diet for two months while the control group had standard diet. These two groups were further divided into three subgroups consisting of ten rats each. After hypercholesterolemia was established, left colon resection and anastomosis were performed in both groups and samples from liver and abdominal aorta were taken to evaluate the systemic effects of hypercholesterolemia. Anastomotic wound healing, blow-out pressures and tissue hydroxyproline levels were evaluated. RESULTS： The test group had a significant weight gain in two months. Microscopic examination of the abdominal aorta revealed no atherosderotic change in none of the groups, but liver tissue specimens showed significant steatosis in the test group. Tissue hydroxyproline levels and anastomotic blow-out pressures were significantly lower in the test group than in the controls. CONCLUSION： Hypercholesterolemia not only increases hydroxyproline levels and blow-out pressures but also worsens anastomotic wound healing.

THE INHIBITORY EFFECT OF ASTRAGALUS MEMBRANACEUS ON COXSACKIE B－3 VIRUS RNA REPLICATION

Using mice infected with coxsackie B-3 virus (CVB3) as a viral myocarditis model, we observed the inhibitory effect of Astragalus membranaceus (AM) on CVB3-RNA replication in myocardial tissue of mice by RNA-RNA in situ hybridization with negative-strand RNA Probes labelled with ￣(35)S and quantitative imaging analysis of positive signals. The mechanism of its effect on CVB3-RNA replication has been investigated by detection of beta-interferon (β-IFN) as well. Results showed that the copy numbers of CVB3-RNA as well as the histologic scores (necrosis) in myocardial tissues of infected-AM treated mice were significantly lower than those in infected and normal saline treated mice, suggesting that AM could inhibit the replication of CVB3-RVA,but its effect on CVB3-RNA replication had no correlation with induction of β-IFN.

Resveratrol prolongs allograft survival after liver transplantation in rats

AIM： To study the immuno-modulatory effect of resveratrol （RES） on allograft rejection after liver transplantation in rats. METHODS： Male Sprague-Dawley （SD） rats were selected as donors and male Wistar rats as recipients for a rejection model. The recipients were divided into four groups after orthotopic liver transplantation （OLTx）. In the RES A, B, and C groups, RES was given intra-peritoneally once a day （25, 50, and 100 mg/kg, respectively） after OLTx, whereas in the control group, vehicle buffer was given intra-peritoneally once a day. The survival time, serum chemistry, production of cytokines, activation of transcription factor NF-kB, and histopathologic findings were then compared among these groups. RESULTS： The mean survival time after OLTx in the RES C group was significantly longer than that in the control group （16.7＋-1.2 d ,vs9.3＋-0.6 d, P〈0.01）. On the 7th posttransplant day the serum albumin level significantly improved in the RES C group, the serum total bile acid and alanine aminotransferase （ALT） levels were significantly lower in the RES C group, the serum IL-2 and INF-y levels were significantly lower in the RES C group, and the activation of transcription factor NF-kB in peripheral blood T lymphocytes was significantly suppressed in the RES A, B, and C groups in comparison to those in the control group. On the 7^th post-transplant day, a histological examination revealed apparent difference in the severity of rejection between the RES C group and control group. CONCLUSION： RES has an immuno-suppressive property as well as protective effect on hepatocytes under allograft rejection. It might serve as a novel agent for reducing the severity of hepatic allograft rejection in rats.

Effect of indomethacin on electrical field stimulation-induced contractions of isolated transverse and longitudinal rat gastric fundus strips

AIM: To study the effects of indomethacin on the isolated transverse and longitudinal rat gastric fundus strips.METHODS: The strips were suspended in an organ bath containing oxygenated Krebs solution, and contractile responses to electrical field stimulation were recorded on a physiograph in an isotonic manner after administration of cumulative concentrations of indomethacin. The effects of indomethacin on the strips pretreated with KATP channel modulators, diazoxide and glybenclamide were studied.RESULTS: Treatment of the transverse strips with indomethacin resulted in a concentration-dependent inhibitory response. In longitudinal strips, biphasic responses were seen, which included a stimulatory response at low concentrations of indomethacin, followed by an inhibitory response at higher concentrations.Diazoxide pre-treatment inhibited the stimulatory response of longitudinal strips. Glybenclamide pre-treatment not only blocked inhibitory effect of the low concentrations of indomethacin on transverse strips, but also increased the amplitude of contractions. Moreover, the drug decreased the amplitude of contractions in longitudinal strips.CONCLUSION: Responses of the isolated longitudinal and transverse rat gastric fundus strips to indomethacin are not similar, and are influenced by KATP channel modulators.