苦楝化学成份的研究

从苦楝(Melia azedarach L.)果中分得苦楝新醇(Ⅰ),苦楝醇(Ⅱ)、苦楝酮(Ⅲ)、苦楝二醇(Ⅳ)、香草醛(Ⅴ)和香草酸(Ⅵ)。根据波谱(IR,MS,¹HNMR,¹³CNMR)分析和理化常数测定,确定了它们的结构。其中苦楝新醇(Ⅰ)为新化合物,对菜青小虫有一定的拒食活性。     

骨髓间充质干细胞移植后脑梗死大鼠脑电图的变化

目的:对比观察骨髓间充质干细胞移植前后脑梗死大鼠脑电图的变化。方法:实验于2002-09/12在解放军第三军医大学中心实验室及西南医院神经内科肌电图室完成。①实验分组:选取清洁级健康成年Wistar大鼠15只,随机数字表法分为干细胞移植组、模型对照组、假手术组,5只/组。②实验方法:另取2只健康幼年Wistar大鼠用于骨髓间充质干细胞的提取,联合采用密度梯度离心及贴壁法分离培养大鼠骨髓间充质干细胞,选取生长良好的1～3代细胞用于移植实验。干细胞移植组、模型对照组大鼠建立大脑中动脉栓塞模型。假手术组仅分离颈总动脉、颈外动脉和颈内动脉,不予结扎和放置线栓。造模后1周,干细胞移植组、假手术组大鼠行细胞移植,在立体定向仪定位下于脑梗死区(壳核)直接注射骨髓间充质干细胞悬液5μL,细胞浓度1×104μL-1,移植坐标为前囟前1.0mm,右旁开3.0mm,硬膜下5.0mm。模型对照组大鼠于相同部位注射等量不含细胞的磷酸盐缓冲液。③实验评估:采用脑电图机分别于造模前、造模后1周(移植前)、细胞移植后4周对各组大鼠进行脑电图检测。结果:15只大鼠均进入结果分析。①造模前基本节律为8～11Hz、15～30μV的α波,间或少量θ波,双侧对称。②造模后1周,假手术组异常率为0;模型对照组20%(1/5)轻度异常,80%(4/5)中度异常;干细胞移植组20%(1/5)轻度异常,60%(3/5)中度异常,20%(1/5)重度异常。③细胞移植后4周,假手术组脑电图恢复正常;模型对照组随术后时间的延长慢波有所减少,但仍可见到δ波、棘波、棘慢波的发放,至细胞移植后4周60%(3/5)轻度异常,40%(2/5)中度异常;干细胞移植组术后局限性慢波逐渐减少,基本节律全部恢复为α波,不对称的情况明显好转,至细胞移植后4周60%(3/5)轻度异常,以病灶侧局限性θ波较多为主,另外40%(2/5)基本正常。结论:动物实验显示骨髓间充质干细胞移植对脑梗死大鼠的脑电图背景节律有改善作用,一定程度上促进了神经系统功能的恢复。     

Sumatriptan - Nonresponders: A Survey in 366 Migraine Patients

Sumatriptan, notably after subcutaneous administration, is highly effective in the acute treatment of migraine in the majority of patients. The response is consistent within patients and over time. To determine risk factors for nonresponse to sumatriptan, we compared clinical characteristics. In responders and nonresponders and, within patients, between attacks with and without response. We found no differences at the strict level of significance (P<0.001 because of multiple comparisons), but only tendencies for differences (0.001相似文献   

Radiation-induced red cell damage: role of reactive oxygen species

BACKGROUND: Cellular blood components are irradiated to prevent graft- versus-host disease in transfusion recipients at risk for this syndrome. Because gamma radiation can result in the production of reactive oxygen species, the role of reactive oxygen species was investigated in radiation-induced red cell damage. STUDY DESIGN AND METHODS: Whole blood from normal donors was exposed to various doses of t-butyl hydroperoxide (0-1 mM) and/or to gamma-radiation (0-50 Gy). Oxidative damage was assessed by the extent of lipid peroxidation (measured by thiobarbituric acid-reactive substances [TBARS]) and hemoglobin oxidation. Fresh blood was divided into three parts-one initially irradiated and stored, another stored with portions irradiated weekly, and a third stored without irradiation. TBARS and hemoglobin oxidation were measured weekly. RESULTS: As expected, t- butyl hydroperoxide induced TBARS formation and hemoglobin oxidation in a dose-dependent fashion. The gamma-radiation not only increased hemoglobin oxidation and TBARS formation, but also enhanced the t-butyl hydroperoxide effect on red cells. Red cell storage increased TBARS generation and hemoglobin oxidation in a time-dependent fashion. When radiation was administered either initially or after weekly storage, TBARS production and hemoglobin oxidation were increased over that measured in unirradiated paired controls. CONCLUSION: Gamma radiation at clinically used doses increases lipid peroxidation and hemoglobin oxidation in human red cells. The effect of gamma-radiation is accentuated by blood storage and induces damage independent of time of storage.     

蒿甲醚对大鼠肺泡Ⅱ型上皮细胞DNA的影响

目的:蒿甲醚除了具有良好的临床治疗作用外,对正常组织有极大的副作用。实验拟观察蒿甲醚对大鼠肺泡Ⅱ型上皮细胞的影响。方法:实验于2005-09-20/2007-03-10在山东省泰山医学院生命科学研究所、中心实验室和机能实验室完成。①实验材料:蒿甲醚购自昆明制药厂,分析纯,使用前先进行预处理,处理方法:研磨后用溶液配成1g/L的母液,超声助溶解后供实验用。Wistar大鼠70只,体质量(70±15)g,雌雄不拘,由山东大学医学院实验动物中心提供。实验过程中对动物处置符合动物伦理学标准。②实验方法:将大鼠随机分为普通饲料对照组(n=10)和实验组(n=60),实验组分6个亚组,分别在饲料中加入0.1,0.2,0.4,0.8,1.6,3.2mg/kg的蒿甲醚。采用单细胞凝胶电泳技术观察大鼠肺泡Ⅱ型上皮细胞DNA的改变。结果:70只大鼠,饲养过程中实验组死亡6只,死亡原因为饲料添加蒿甲醚造成。当饲料中的蒿甲醚浓度为0.1mg/kg时,大鼠肺泡Ⅱ型上皮细胞DNA损伤率与对照组相比,差异无统计学意义;饲料中的蒿甲醚浓度超过0.2mg/kg时,大鼠肺泡Ⅱ型上皮细胞DNA损伤率明显增加,与对照组相比,差异有统计学意义。且损伤程度与饲料中蒿甲醚含量呈正相关。结论:当饲料中的蒿甲醚浓度超过0.2mg/kg时,蒿甲醚可在一定程度上改变肺泡Ⅱ型上皮细胞的DNA生物学特性。且随着蒿甲醚浓度的升高,这种损害更为明显。     

颈动脉内中膜厚度与初诊2型糖尿病视网膜病变的关系

目的:研究发现,糖尿病视网膜病变和动脉粥样硬化终点事件相关。试验拟验证颈动脉内中膜厚度与初诊汉族2型糖尿病患者糖尿病视网膜病变相关危险因素的关系。方法:①试验对象:选择2006-06/2007-06本院住院的初诊2型糖尿病患者187例,男114例,女73例;平均年龄(51±14)岁;平均体质量指数(24.7±4.7)kg/m2。均符合1997年美国糖尿病协会的2型糖尿病诊断标准,排除既往已存在心血管疾病者。患者对治疗及试验均知情同意。根据眼底照相检查结果,将所有受检者分为糖尿病视网膜病变组及非糖尿病视网膜病变组进行统计分析。②试验方法及评估:所有患者询问一般情况,测量颈动脉内中膜厚度以及相关生化指标,对糖尿病视网膜病变相关因素进行单因素及多因素Logistic回归分析。结果:纳入2型糖尿病患者187例,均进入结果分析。单因素Logistic回归分析显示,高血压、糖尿病家族史、颈动脉内中膜厚度、尿白蛋白、低密度脂蛋白胆固醇与糖尿病视网膜病变发生呈显著正相关,多因素Logistic回归分析未见显效因素。结论:单因素回归分析中颈动脉内中膜厚度及其他4项指标与糖尿病视网膜病变相关,而多因素回归分析这些因素未进入主效基因模型。     

Practical guidelines for process validation and process control of white cell-reduced blood components: report of the Biomedical Excellence for Safer Transfusion (BEST) Working Party of the International Society of Blood Transfusion (ISBT)

Background: The increased use of white (WBC)-reduced blood components has prompted many institutions to develop quality assurance programs directed to such component preparation processes. For consistent preparation of WBC-reduced blood components that meet clinical needs as well as national standards, a program of process validation and control should be instituted. This involves controlling key factors that affect WBC reduction as well as periodic monitoring of the residual cellular content of components. Practical guidelines for the implementation of such a program are provided. Study Design and Methods: A program involving three phases of monitoring was developed by individuals belonging to an international working party of the International Society of Blood Transfusion. Results: The first phase, process validation, evaluates a minimum of 20 consecutive units (a minimum of 60 units when nonparametric measurements are used) to document the successful local implementation of a new or substantially modified process. Ongoing process control employing Levey-Jennings type control charts is used to demonstrate that the process remains stable over time. Process capability assessment and conformance with standards are evaluated once residual WBCs are counted in a sufficient number of units. This enables a facility to claim with a specified degree of confidence that a stated proportion of WBC-reduced units will meet national standards. Two approaches to determine the number of units that should be selected for counting are presented. The first approach considers units as either acceptable or not acceptable and assumes that the distribution of failed (or nonconforming) units approximates the Poisson distribution. The second approach takes into consideration the observed WBC content of the tested units, with the assumption that the residual WBC content in WBC-reduced components follows a lognormal distribution. A method to assess the lognormal distribution of residual WBCs is presented. Specific tables based on each of these approaches are provided to guide the reader in the design of a program that will verify conformance with any national standard at specific confidence levels. The approach can be generalized to other process control applications. Conclusion: Guidelines are presented for process validation, process control, and assessment of conformance in the production of WBC-reduced blood components. Policy makers retain the responsibility to establish, on the basis of the expected use of WBC- reduced components, requirements for the frequency of testing and for the proportion of prepared units that are expected with a stated degree of confidence to meet the standards. Facilities preparing WBC-reduced components can monitor key factors that influence the preparation of WBC-reduced blood, can periodically assess their conformance with the standards, and can intervene to correct adverse changes in the process. This approach can be used to ensure the consistent quality of WBC- reduced blood components.     

Collection and transfusion of blood and blood components in the United States, 1992

BACKGROUND: Studies were conducted to measure the state of the United States' national blood resource in 1992 and changes therein from 1989. STUDY DESIGN AND METHODS: With data supplied by the American Red Cross and the American Association of Blood Banks, as well as data from a stratified random-sample survey of 3350 non-American Association of Blood Banks hospitals, statistical methods were applied to estimate national blood activities in 1992. RESULTS: The total US blood supply in 1992 was 13,794,000 units, a decrease of 3.1 percent from 1989. Some 11,307,000 red cell units were transfused to 3,772,000 patients, an average of 3.0 units per transfused patient. Preoperative autologous blood deposits totaled 1,117,000 units, a 70-percent increase over 1989. Of this number, 566,000 units (50.7%) were transfused, 5,000 (4.4%) transferred to the allogeneic supply, and 546,000 (48.9%) discarded. Of 436,000 directed-donation units, 136,000 (31.2%) were transfused, 57,000 (13.1%) transferred to allogeneic supply, and 243,000 (55.7%) discarded. The total allogeneic blood supply, including imports, decreased by 7.4 percent from 1989, and allogeneic blood transfusions, including those to children, decreased by 8.6 percent. Over 8,300,000 platelet units were transfused; of these, some 3,600,000 were apheresis platelets. In addition, 2,255,000 units of plasma and 939,000 units of cryoprecipitate were transfused. CONCLUSION: While the US blood supply was adequate for transfusion needs in 1992, blood collections and red cell transfusions had decreased substantially since 1989.