^1H-magnetic resonance spectroscopy screening for animals with acute cerebral infraction suitable forthrombolytic therapy

BACKGROUND: As a non-invasive technique which can provide comprehensive biological information, 1H-magnetic resonance spectroscopy (1H-MRS) may provide valuable reference data for irreversible recovery or reversible changes in ischemic tissue after stroke. OBJECTIVE: To monitor and evaluate the effect of the urokinase thrombolytic therapy after experimental acute cerebral ischemia by 1H-MRS technology and investigate its adaptability. DESIGN: Randomly controlled animal study. SETTINGS: Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science. MATERIALS: Eleven healthy adult Sprague-Dawley (SD) rats, weighing 260–300 g and of both genders, were supplied by Experimental Animal Center of Tongji Medical Collage, Huazhong University of Science and Technology [SCXK (e) 2004-007]. 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company. METHODS: The experiment was carried out in Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science from August 2003 to December 2005. ① The rats were randomly divided into 30-minute self-thrombo-embolism group (n =6) and 60-minute self-thrombo-embolism group (n =5). Six rats in 30-minute self-thrombo-embolism group were occluded with clot embolus for 30 minutes and 5 rats in 60-minute self-thrombo-embolism group were occluded for 60 minutes. 10 000 U/kg urokinase was dissolved in 2 mL saline and the operation lasted for 5 minutes. ② 1H-MRS was performed before thrombolysis and at 3 hours and 24 hours after successful embolization. The metabolic changes of N-acetyl-L-aspartic acid (NAA)/phosphocreatine (PCr) + creatine (Cr), choline phosphate (Cho)/PCr+Cr and lactic acid (Lac)/PCr+Cr in the region of interests were analyzed. ③ The T2W image was conducted 24 hours after the thrombolytic therapy with TR=500 ms and TE=25 ms. ④ The subjects were sacrificed immediately after 1H-MRS and the brain tissues were cut into pieces and stained with HE method; in addition, pathological changes were observed under optic microscope. MAIN OUTCOME MEASURES: ① Metabolic changes of NAA/PCr+Cr, Cho/PCr+Cr and Lac/PCr+Cr in the region of interests; ② T2W image at 24 hours after the thrombolysis; ③ pathological observation of brain tissue. RESULTS: Eleven rats were all involved in the final analysis. ① Metabolic changes in the region of interests : In 30-minute self-thrombo-embolism group, the Lac peak emerged immediately after the embolism, but the ischemic zone decreased 3 hours after the thrombolytic therapy (0.252±0.01, 0.603±0.01, P < 0.01). Lac/(PCr+Cr) ratio was 0.290±0.01 at 24 hours after thrombolysis, which was higher than that at 3 hours after thrombolysis (P < 0.01). The NAA/ (PCr+Cr) ratio decreased significantly at 3 hours after the thrombolysis as compared with that before thrombolysis (0.922±0.16, 1.196±0.01, P < 0.05). In 60-minute self-thrombo-embolism group, the Lac/(PCr+Cr) ratio was higher at 3 hours after thrombolysis than that before thrombolysis (0.846±0.12, 0.601±0.11, P < 0.05) and the NAA/(PCr+Cr) decreased at 3 hours after the embolism. Fluctuation of NAA/ (PCr+Cr) ranged from 0.68 to 0.75 before thrombolysis and from 0.71 to 0.75 at 3 hours after thrombolysis. ② T2W image: T2W image showed that 2 subjects in 30-minute self-thrombo-embolism group whose Lac/NAA was higher than 0.7 suffered from intracranial hemorrhage. This meant that the subjects with Lac/NAA > 0.7 were more likely to suffer from intracranial hemorrhage. ③ Histological and morphological examinations: Optic microscope demonstrated that interspace surrounding nerve cells was widened at ischemic center; neurons were swelling; nucleus was stained lightly; pyknosis and mesenchymal edema were mainly observed in lateral cortex of brow and vertex and in lateral part of corpus striatum. CONCLUSION: ①Compound parameters in ischemic area before thrombolysis should be regarded as an important predicting marker for thrombolytic therapy, effect evaluation and termination. ② 1H-MRS combining with other imaging technique is a detecting way for screening cases who are suitable for thrombolytic therapy.     

桂林市传染病网络直报工作第一年效果分析

目的观察传染病网络直报系统启动一年来的传染病监测质量,探讨网络直报评价方法.方法描述研究网络直报工作效果.结果实行网络直报后,传染病从临床医生发现到疾病预防控制机构接到报告的平均时间由5.48 d缩短至1.67 d,报卡数量增加20.84%,21.03%的报告卡得到校正,网络直报覆盖率县辖区医院为96.55%,市城区为69.23%,79.21%的直报单位有专用电脑.结论网络直报的启用及其系统的建立,提高了桂林市传染病疫情报告的质量和水平,同时应尽快建立与之相应的疫情报告管理方法和标准.     

胰岛素瘤的诊断和治疗：附137例报告

目的总结胰岛素瘤的诊断方法和外科治疗效果。方法回顾性分析近26年来收治的胰岛素瘤137例患者的临床资料。结果男77例,女60例。137例均具有典型的Whipple三联症。B超,CT,MRI检查的阳性率分别为35.1%,67.9%,58.1%。126例手术治疗患者中,102例(80.9%)行胰岛素瘤摘除术,4例(3.2%)行胰十二指肠切除术,16例(12.7%)行胰体尾切除术,另外4例(3.2%)行开腹探查术。切除的122例肿瘤中,良性占96.7%,恶性3.3%;单发肿瘤98.4%,多发1.6%。86.9%肿瘤直径≤2.0cm。13.1%肿瘤位于胰头;位于胰体和胰尾者分别为46.7%和40.2%。结论Whipple三联症,结合IRI,IGR,C-肽,以及胰岛素原的检测水平,可作为胰岛素瘤的定性诊断依据。胰岛素瘤的定位诊断仍很困难,联合应用多种影像学检查方法有助于提高检出率。治疗首选肿瘤摘除术,如果术中探查未能找到肿瘤,不宜盲目行胰体尾切除术,应排除其他原因所致低血糖症,同时进一步完善影像学检查方法,明确定位后,再考虑二次手术治疗。     

兔内听动脉阻断与听觉改变的关系

目的 探讨实验性内听动脉阻断与术后听力改变的关系及术中听觉监控的方法。方法 实验兔乙状窦后进路暴露小脑桥脑角，下压小脑暴露内听道及第Ⅷ神经复合体，分辨出内听动脉，予阻断不同时间，分别行蜗神经直接复合动作电位(DCAP)和畸变产物耳声发射记录(DPOAE)。结果对照组DCAPN1波潜伏期值无明显改变。内耳血供阻断10s和30s组在压迫开始后3min，DCAPN1波潜伏期值均恢复为初始值。内耳血供阻断1min组在压迫开始后3h，DCAPN1波潜伏期值未恢复为初始值假手术组DPOAE幅值无明显改变，内耳血供阻断10s、30s对DPOAE幅值无影响，内耳血供阻断1min使得DPOAE幅值下降结论兔内耳血供阻断1min可能造成兔听觉不可逆损伤。DCAP、DPOAE能有效、持续地监控内耳血供阻断，是耳神经外科手术中实用的听觉监测手段。     

应用VTK技术建立唇腭裂可视化模型

目的:寻求一种高效率、高精度建立唇腭裂患者颌面部可视化模型的方法.方法:利用薄层CT获取原始数据,运用k-均值聚类算法进行图像分割,结合VTK(Visualization Toolkit)技术进行可视化模型的建立.结果:建立了更为精确的唇腭裂患者颌面部的可视化模型,总结出了一种更为方便高效的通用可视化建模方法.结论:应用VTK方法建立可视化模型,软件开发周期更短,精度更高,应用更广泛.     

Ovid医学信息平台在医学科研中的应用

详细介绍了Ovid 医学信息平台的特点及功能,并对其数据库所涉及学科作了介绍,指出Ovid 医学信息平台以其超大容量、完美服务及快捷查阅等特点优于同类软件,可以为医学科研人员提供高质量、深层次、全方位的服务.     

荧光分光光度法检测半乳糖化白蛋白磁性阿霉素纳米粒在大鼠体内分布的研究

目的观察由半乳糖化白蛋白磁性纳米粒运载的阿霉素经舌静脉给药后在大鼠体内的的分布状况.方法全部大鼠随机分为四组,经舌静脉,按分组分别注射相应药物,剂量均为阿霉素2.5 mg/kg体重.取全血、心、肺、肝、脾、肾.全血制成血浆,器官组织制成匀浆,盐酸乙醇法提取阿霉素,用荧光光度计测量.结果静脉注射同等剂量、不同剂型的阿霉素药物后,阿霉素在器官中的蓄积程度从高到低:肝:D靶肝＞D非靶肝、C＞B＞A;心脏、肾、血浆:A＞B＞D、C;脾:B＞A、C、D;肺:B＞A＞C、D.磁性阿霉素白蛋白纳米粒注入体内后,在心、肺、肝、脾、肾中的药物浓度在15～30min达峰值,而半乳糖化后,阿霉素的药物峰值提前到5 min或之前.外加磁场和未加磁场的半乳糖化白蛋白磁性阿霉素纳米粒组的药物靶向指数和药物选择指数是均高于磁性白蛋白纳米粒.结论磁性阿霉素白蛋白纳米粒经半乳糖化后,可显著增强阿霉素对肝脏的靶向性,并显著降低心、肺、脾、肾、血浆肝外器官的组织阿霉素浓度.利用外加磁场,可提高阿霉素在肝脏特定部位蓄积的能力.因此,静脉注射半乳糖化白蛋白磁性阿霉素纳米粒是可行的.     

外加磁场对半乳糖化白蛋白磁性阿霉素纳米粒在大鼠体内分布影响的研究

目的观察半乳糖化白蛋白磁性阿霉素纳米粒(ADR-GHMN)在正常肝脏中的靶向性,并观察ADR-GHMN在全身各脏器的分布特征及外加磁场对其分布的影响.方法大鼠正中开腹,肝动脉插管并固定,肝动脉注射125I-ADR-GHMN(相当于阿霉素0.5 mg/kg),左外叶加磁场,磁场应用30 min,移去磁场后,动物立即处死;对照组:肝动脉注射ADR-GHMN,左外叶不加磁场,30min后,移去磁场后,动物立即处死,立即取靶区肝、非靶区肝、肾、心、肺、小肠、脾及周围血作γ计数.肝组织作病理切片.结果注入的纳米粒75～85%分布于肝脏,其它脏器极少.病理切片显示磁区小动脉见大量纳米粒存在,对照组及非磁区肝中纳米粒很少见.结论ADR-GHMN在正常肝组织中有明显的磁靶向性;在磁场作用下,ADR-GHMN主要分布于肝脏,其它脏器含量很少;试验组肾、心、肺、小肠、脾及外周血于对照组的放射活性比较明显降低,表明磁性物质的存在使这些脏器的相对药物暴露明显减少.     

MR显微成像检测活体阿尔茨海默病转基因小鼠老年斑沉积的效果

目的利用MR显微成像技术研究阿尔茨海默病转基因小鼠老年斑的沉积情况。方法2只17个月龄阿尔茨海默病转基因[V717I]小鼠和2只野生型小鼠，行活体T2WI，然后对照影像定位结果进行组织学切片及免疫组织化学染色。观察T2WI中老年斑的沉积情况以及其与免疫组织化学染色结果的对应关系。结果转基因小鼠T2WI上显示大脑皮层和海马区可见点状低信号，且部分低信号可以和组织学切片所显示的老年斑相对应；野生型小鼠T2WI未见明显的低信号，免疫组织化学染色也未见到染色阳性的斑块。结论MR显微成像技术检测老年斑的沉积是可行的，且可用来特异性地诊断阿尔茨海默病。     

Effect of nuclear factor-κB p65 ASOND on I typ collagen expression and rat hepatic stellate cells proliferation

Objective Sstudy effect of nuclear factor-κB ASOND on I type collagen expression and rat hepatic stellate cells(HSC)proliferation.Methods Rat HSCs were separated by affusing and digestingof Ⅳ type collagenenzyme and density acentric method.Lipid-mediated NF-κB p65 ASOND(0.001,0.01,0.1,1μmol/L)Was transferred into rat HSCs.Toxicity of HSCs caused by NF-κB p65 ASOND and activity of LDH were determined by trypan blue staining.Proliferation affection of transferring NF-κB p65 ASOND into HSCs was determined by MTT.In different concentration NF-κB p65 ASOND.expression of Ⅰ type collagen stimulated by 1mg/L TNF-αwas determined by RT-PCR and ELISA.Results After transfection of NF-κB p65 ASODN,expression of NF-κB protein in HSCs was decreasing.Toxicity experiment indicated that NF-κB p65 ASOND of different concentration(0.001,0.01,0.1 and 1.0 μmol/L)had no effect on HSCs livability and LDH activity(P<0.05).Four different concentration NF-κ B p65 ASOND could restrain HSCs proliferation stimulated by 1 mg/L TNF-α.The expression of I type collagen and mRNA stimulated by 1mg/LTNF-αwas increased,and had a positive correlation with concentration(P>0.05).Conclusion NF-κB p65 ASOND may depress NF-κB activity to restrain HSCs proliferation and Ⅰ type collagen expression,and reduce extracellular matrix.