Should post-trial provision of beneficial experimental interventions be mandatory in developing countries?

The need for continuing provision of beneficial experimental interventions after research is concluded remains a controversial topic in bioethics for research. Based on the principle of beneficence, justice as reciprocity, concerns about exploitation and fair benefits, participants should be able to have continuing access to benefits beyond the research period. However, there is no consensus about whether or not post-trial provision of beneficial interventions should be mandatory for participants from developing countries. This paper summarises recommendations from international and national guidelines. Ethical principles and practical issues relating to post-trial provision are also discussed. In conclusion, post-trial provision is not necessary in all situations and a set of criteria are proposed to identify the situations that beneficial interventions should be provided beyond the research period. However, mandatory post-trial supply of beneficial experimental interventions should be assured for those who still need and are able to benefit from them but have no alternative access. Mandatory provision is based on universal bioethical principles such as beneficence and justice. Furthermore, difficulties associated with implementation of post-trial provision are not unmanageable. Careful advanced planning and a comprehensive partnership among relevant parties would be very helpful in solving these difficulties in practice, which therefore should not be taken as an excuse to escape post-trial responsibility.     

咪唑斯汀对致敏小鼠脾淋巴细胞释放LTB_4和IL-5的抑制作用

目的　观察咪唑斯汀对卵蛋白(OVA)致敏的小鼠脾淋巴细胞释放白三烯B4 (LTB4)和白介素5 (IL 5)的影响。方法　实验第1天及第15天给小鼠腹腔注射OVA,构建致敏动物模型,分离实验小鼠脾淋巴细胞进行培养,以不同浓度咪唑斯汀及对照药物预处理,加入OVA再次刺激,采用竞争酶联免疫吸附法(CompetitiveELISA)检测培养细胞上清液中LTB4及IL 5水平。结果　致敏组小鼠脾淋巴细胞培养上清液中LTB4和IL 5水平分别为1 1 1. 0 6±1 5. 9 8pg/ml和333. 54±24. 76pg/ml,较正常组小鼠显著升高(P<0. 01)。1. 0μmol/L和10μmol/L的咪唑斯汀可显著抑制致敏小鼠脾淋巴细胞产生LTB4和IL 5。对照药物为1. 0μmol/L的地塞米松,对LTB4和IL 5的释放均具显著抑制效应;而10μmol/L的扑尔敏及氯雷他定对LTB4和IL 5的抑制不明显。结论　咪唑斯汀对致敏小鼠脾淋巴细胞LTB4和IL 5的释放具有剂量依赖性的抑制作用。     

推拿结合穴位注射治疗腹泻型肠易激综合征疗效观察

目的：观察推拿结合穴位注射黄芪注射液治疗腹泻型肠易激综合征（irritable bowel syndrome,IBS）的临床疗效。方法：将70例患者按随机数字表单盲法分为两组,对照组35例口服匹维溴胺和培菲康治疗;治疗组35例采用推拿结合穴位注射黄芪注射液治疗;两组均治疗28 d。结果：治疗组有效率高于对照组,治疗组在腹泻、腹痛症状改善方面疗效优于对照组。结论：推拿结合穴位注射黄芪注射液治疗腹泻型IBS效果明显。     

Metabolomics analysis of multidrug-resistant breast cancer cells in vitro using methyl-tert-butyl ether method

The comprehensive characterization of metabolome and lipidome to reveal unknown pathological conditions, are being used to investigate the molecular mechanisms of cancer, especially in the field of early diagnosis, treatment, and prognosis. The multidrug resistance (MDR) of tumor cells limits the therapeutic effect of anti-cancer drugs and is the main obstacle for chemotherapy. Here, we adopted a methyl-tert-butyl ether (MTBE)-based extraction method to simultaneously extract small polar molecules and lipophilic metabolites for nontargeted metabolomics of multidrug-resistant breast cancer cell line MCF-7/ADR and its parental cell line MCF-7/S by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Distinctly different metabolic features were shown between MCF-7/ADR cells and MCF-7/S on the basis of multivariate analyses. 17 potential biomarkers were identified. And these potential biomarkers were mainly correlated with cell membrane lipids composition, cell signaling regulated by lipids, and anti-oxidation ability. The studies of cellular ultrastructure and morphology by in situ atomic force microscopy (AFM) also demonstrated the cellular membrane changed along with the MDR. We expect that this study could provide a new method for monitoring drug resistance during clinical chemotherapy and be useful for the development of drugs to overcome the MDR.

MTBE-based cellular lipidomics to investigate the mechanisms of multidrug resistance of breast cancer.     

城市固体废物产生量与经济增长脱钩关系的实证研究——以北京市为例

采用脱钩理论的3种评价方法 (脱钩指数法、IPAT模型法以及弹性分析法)对北京市城市固体废物产生量与经济增长之间的状态进行对比分析,发现:3种评价方法的原理不同,但评价结果基本一致,但Tapio(2005)提出的弹性分析法模型在指标细分上存在问题;北京市1979—2011年城市固体废物产生量总体实现相对脱钩,但通过分析个别年份状态数据发现要真正实现城市固体废物的减量化需要管理制度的改进,以及市民环保素质的提升。     

晚期日本血吸虫病肝组织学与肝纤维化指标的相关性研究

目的探讨晚期血吸虫病(晚血)血清肝纤维化指标及其肝组织内的表达与肝纤维化检查的肝组织病理活检的相关程度。方法肝组织手术活检标本经10%甲醛固定,常规石蜡包埋切片,HE染色,光镜下病理学检查。肝组织基质金属蛋白酶-1(MMPS-1)、基质金属蛋白酶组织抑制因子-1(TIMPS-1)、转化生长因子-β1(TGF-β1)采用免疫组化染色S-P法。血清MMPS-1、TGF-β1检测采用酶联免疫吸附试验(ELISA)法,TIMPS-1检测采用免疫透射比浊法。结果共检测晚血脾切除患者45例。肝组织病理学检查按Scheuer分级S13例(6.0%)、S25例(11.1%)、S319例(42.2%)、S418例(40.0%)。肝组织免疫组化MMPS-1“ ”27例(60.0%),“ ”10例(22.2%),“ ”1例(2.2%);TIMPS-1“ ”8例(17.8%),“ ”18例(40.0%),“ ”13例(28.9%)。TGF-β1“ ”8例(17%),“ ”22例(48.9%),“ ”10例(22.2%)。血清MMPS-1、TIMPS-1、TGF-β1含量除MMPS-1外,均随肝纤维化程度加重和免疫组化阳性表达强度的增强而增高。结论晚血肝组织病理学检查肝纤维化程度的加重与肝组织TIMPS-1、TGF-β1免疫组化阳性表达强度及血清含量呈正相关;检测血清TIMPS-1、TGF-β1含量及TIMPS-1/MMPS-1比值是肝纤维化诊断和疗效评价较好的无创伤性指标。     

苦瓜蛋白对柯萨奇B3病毒性心肌炎小鼠半胱天冬酶3活性及凋亡的抑制作用

为研究苦瓜蛋白对凋亡的关键酶半胱天冬酶 3及凋亡的调节作用 ,用已经建立起来的方法从苦瓜果肉中提取苦瓜蛋白。将BALB/C小鼠分为 4组 :病毒对照组、正常对照组、药物对照组和药物治疗组 ,分别在第 0天、第 3天、第 7天和第 14天各处死 5只小鼠 ,第 2 1天全部处死动物 ,心肌组织半胱天冬酶 3活性测定按照CAL BIOCHEM公司的试剂说明书进行 ,并稍加改正 ,凋亡鉴定按照Oncogene公司的TdT DNA裂解片断末端原位标记试剂说明书进行。结果发现 ,①病毒对照组第 7天开始出现半胱天冬酶 3活性 (0 .6 3± 0 .2 1pmol/min ,n =5 ) ,第 14天的活性 (10 .9± 1.5pmol/min ,n =5 )显著高于第 7天 ,第 2 1天的活性 (12 .6± 1.3pmol/min ,n =5 )又高于第 14天。②药物治疗组 ,只有一个第 2 1天的标本有半胱天冬酶 3活性 (0 .4 1pmol/min) ,其它两组均未检测到此酶的活性。③DNA裂解片断末端原位标记法发现 ,病毒对照组在第 7天心肌中有少数细胞凋亡 ,第 14天、第 2 1天凋亡细胞明显增多 ,在非病变区域可发现单个凋亡的心肌细胞。治疗组未发现凋亡细胞 ,其它两组也未发现凋亡细胞。结果提示 ,CVB3病毒性心肌炎中发现有明显的凋亡现象 ,凋亡和半胱天冬酶 3发现于第 7天 ,且随着时间增加而逐渐加重(增强 ) ;苦瓜蛋白可显     

Green and facile edge-oxidation of multi-layer graphene by sodium persulfate activated with ferrous ions

Effective edge oxidation of graphene with high structural integrity is highly desirable yet technically challenging for most practical applications. In this work, we have developed a green and facile strategy to obtain edge-oxidized graphene with good dispersion stability and high electrical conductivity by exploiting high edge reactivity of highly conductive multi-layer graphene and oxidizing radicals (SO₄⁻˙) generated from sodium persulfate (Na₂S₂O₈) with ferrous ion (Fe²⁺) activation. Owing to high structural integrity of pristine graphene and effective edge oxidation, the obtained edge-oxidized graphene exhibited excellent dispersion stability and satisfactory electrical conductivity (i.e. ≥240 S cm⁻¹). Moreover, the oxidation degree of pristine graphene can be well controlled by adjusting treatment time. The obtained edge-oxidized graphene is expected to find a variety of applications in many fields of anti-static films, energy storage materials, flexible sensors and high-performance nanocomposites.

A green and facile strategy is represented to obtain edge-oxidized graphene by exploiting sulfate radicals generated from Na₂S₂O₈ with Fe²⁺ activation.