Current understandings and perspectives on non-cancer health effects of benzene: A global concern

Objective

Benzene, as a volatile organic compound, is known as one of the main air pollutants in the environment. The aim of this review is to summarize all available evidences on non-cancerous health effects of benzene providing an overview of possible association of exposure to benzene with human chronic diseases, specially, in those regions of the world where benzene concentration is being poorly monitored.

Methodology

A bibliographic search of scientific databases including PubMed, Google Scholar, and Scirus was conducted with key words of “benzene toxic health effects”, “environmental volatile organic compounds”, “diabetes mellitus and environmental pollutants”, “breast cancer and environmental pollution”, “prevalence of lung cancer”, and “diabetes prevalence”. More than 300 peer reviewed papers were examined. Experimental and epidemiologic studies reporting health effects of benzene and volatile organic compounds were included in the study.

Results

Epidemiologic and experimental studies suggest that benzene exposure can lead to numerous non-cancerous health effects associated with functional aberration of vital systems in the body like reproductive, immune, nervous, endocrine, cardiovascular, and respiratory.

Conclusion

Chronic diseases have become a health burden of global dimension with special emphasis in regions with poor monitoring over contents of benzene in petrochemicals. Benzene is a well known carcinogen of blood and its components, but the concern of benzene exposure is more than carcinogenicity of blood components and should be evaluated in both epidemiologic and experimental studies. Aspect of interactions and mechanism of toxicity in relation to human general health problems especially endocrine disturbances with particular reference to diabetes, breast and lung cancers should be followed up.     

早期血乳酸水平检测在重症肺炎患者中的临床意义

目的：探讨早期血乳酸水平检测在重症肺炎患者中的临床意义。方法选取本院2011年5月~2014年5月收治的100例重症肺炎患者作为研究对象,根据存活或死亡分为观察组(生存患者)和对照组(死亡患者)。比较两组入院时、入院后6h、入院后24h的血乳酸水平及入院6h的乳酸清除率,记录不同乳酸清除率水平患者的死亡率。结果观察组入院时、入院6 h和入院24 h的血乳酸水平显著低于同期对照组,差异有统计学意义(P<0.05)。观察组入院6 h的乳酸清除率显著高于对照组,差异有统计学意义(P<0.05)。高乳酸清除率患者的死亡率显著低于低乳酸清除率患者,差异有统计学意义(P<0.05)。结论检测重症肺炎患者的血乳酸水平有助于了解患者的预后,血乳酸清除率低的患者死亡率高。     

Mediastinal microdialysis in the diagnosis of early anastomotic leakage after resection for cancer of the esophagus and gastroesophageal junction

Background

Anastomotic leakage (AL) after gastroesophageal resection for cancer is a serious complication. The aim was to evaluate mediastinal microdialysis in the detection of AL before clinical symptoms.

Methods

Sixty patients were included. Samples were collected every 4 hours in the 1st 8 postoperative days and analyzed for several metabolites.

Results

Forty-four patients had an uncomplicated postoperative recovery, 7 developed anastomotic-related complications, and 5 developed major nonanastomotic-related complications. Six patients were excluded (early catheter malfunction and reoperation). Logistic regression model on several metabolites demonstrated a 100% sensitivity, specificity, and positive and negative predictive values regarding the diagnosis of anastomotic complications within postoperative day 7. However, as independent markers, none of the measured metabolites were able to predict AL.

Conclusion

The diagnosis of anastomotic-related complications before clinical symptoms seemed possible by mediastinal microdialysis, but the diagnosis should be based on an interpretation of several metabolic events.     

钠钾镁钙葡萄糖注射液术中输注对患者肝肾功能、血电解质、血糖、血乳酸及凝血功能的影响

目的 评估钠钾镁钙葡萄糖注射液（sodium potassium magnesium calcium and glucose,SPMCG）术中输注对患者肝肾功能、血电解质、血糖、血乳酸及凝血功能的影响.方法 择期拟在全身麻醉下行普外科或骨科手术的患者80例,美国麻醉医师协会（ASA）分级Ⅰ级～Ⅱ级,采用随机数字表法分为实验组和对照组,每组40例.实验组给予SPMCG,对照组给予乳酸钠林格注射液.两组均以15 ml·kg-1·h-1的速度输注500 ml液体后行麻醉诱导,诱导后以10 ml·kg 1·h-1的速度维持输液2h,之后以8 ml·kg-1h-1的速度维持至手术结束.输液前后测定患者的肝肾功能、血电解质以及凝血功能,并监测输液前即刻、诱导前即刻、诱导后1、2h和输液结束时即刻各时间点的血乳酸和血糖值.结果 两组患者输注相应液体后,丙氨酸氨基转移酶（alanine aminotransferase,ALT）、天门冬氨酸氨基转移酶（aspartateaminotransferase,AST）、白蛋白（albumin,ALB）、总胆红素（total bilirubin,TBIL）、血尿素氮（blood urea nitrogen,BUN）和血肌酐（serum creatinine,Cr）与输液前比较差异无统计学意义,组间比较差异无统计学意义.电解质方面,输液后2组Na＋、K＋、Cl-、Ca2＋的浓度差异无统计学意义,但实验组输液后Mg2浓度较对照组高[（0.48±0.21） mmol/L vs（0.71±0.31） mmol/L（P＜0.05）].手术过程中2组患者血糖均逐渐上升,术后又下降至输液前水平.两种液体输注后,凝血酶原时间（prothrombin time,PT）和部分凝血活酶时间（activated partial thromboplastin time,APTT）无显著变化.结论 在术中输注SPMCG,对患者肝肾功能、血电解质、血糖、血乳酸及凝血功能无明显不良影响,并且相对于乳酸钠林格注射液,SPMCG能更好地维持血镁水平.     

LDH enzyme activity in human saliva: The effect of exposure to cigarette smoke and its different components

ObjectiveAldehydes and reactive nitrogen species (RNS) are important chemically active agents in cigarette smoke (CS). Salivary lactate dehydrogenase (LDH) originates predominantly from oral epithelium and was identified as an oral state marker. Its activity in saliva decreases after CS exposure. The aims of the current study were to identify the specific damaging agents in CS responsible for this activity reduction and to understand the mechanisms participating in CS oxidative damage to the salivary enzymes.MethodsPurified and salivary LDH samples were exposed to different levels of CS, pure acrolein, acetaldehyde, peroxynitrite and RNS donors. Each response of the isolated agent to the exposure was examined by a spectrophotometric enzyme activity assay and a Western blot.ResultsCS exposure caused a 34% reduction in LDH activity. Isolated treatment with unsaturated-aldehydes (acrolein, 10 μmol) caused a 61% reduction, while saturated-aldehydes (acetaldehyde, 200 μmol), peroxynitrite (200 μM) and RNS donor (SIN-1, 2 mM) caused no substantial effect. All five LDH isoenzymes reacted similarly. The carbonyl immunoblotting assay revealed a fourfold increase in carbonyl content when treated with CS and a sevenfold increase when treated with acrolein.Conclusionα,β-Unsaturated-aldehydes were identified as the main CS ingredient responsible for salivary LDH activity diminution. The effect of saturated-aldehydes and RNS donors was negligible. Unsaturated-aldehydes are capable of introducing carbonyl group into proteins, causing their dysfunction. This provides a molecular explanation for a decrease in LDH enzymatic activity in saliva.     

乳酸环丙沙星氯化钠注射液无菌检查法的验证

目的：验证乳酸环丙沙星氯化钠注射液的无菌检查方法。方法：采用中国药典2005年版二部附录无菌检查法项下薄膜过滤法。结果：确定大肠埃希菌为乳酸环丙沙星氯化钠注射液无菌检查的敏感菌株。结论：经方法学验证，该方法准确可靠，可作为乳酸环丙沙星氯化钠注射液的无菌检查方法。     

锡兰绿茶中黄酮类成分对缺氧人脑上皮细胞的治疗作用

为研究从锡兰绿茶（Dilmah）提取纯化的黄酮类有效成分对缺氧人脑上皮细胞的治疗作用，体外培养人脑上皮细胞（HBEC），给与锡兰绿茶黄酮提取物治疗后造缺氧模型，检测锡兰绿茶中的黄酮类化合物的抗氧化活性及脑细胞的生存情况，探究其对缺氧脑细胞氧化应激的影响。生化检测显示锡兰绿茶提取物的自由基的清除抑制率（ABTS）为68％±2．8％，次氯酸漂白邻苯三酚红抑制率为79％±4．5％。缺氧后，空白对照组细胞生存率为29％±2．3％，而锡兰绿茶黄酮提取物治疗组为41％±4．7％，氯沙坦治疗组为39％±3．1％。同时，黄铜提取物与氯沙坦治疗组LDH释放分别减少75％±3．7％和79％±3．5％。锡兰绿茶的黄酮提取物治疗使细胞抗氧化酶活力显著增强，SOD：（1．5±0．6）μmol／min／mg蛋白，CAT：（0．61±0．06）μmol／min／mg蛋白，GPx：（2．6±0．41）μmol／min／mg蛋白，GST：（6．0±2．4）μmol／min／mg蛋白，显著高于缺氧对照组，其酶活力分别为：（0．5±0．52，51±0．04，1．2±0．35，3．1±1．6）μmol／min／mg蛋白。研究结果表明，锡兰绿茶有很大的临床应用价值。饮用锡兰绿茶可能成为预防中风的有效新方法，并能减少现代疾病对生命的威胁，提高人类生活质量。     

三七皂苷对氧化低密度脂蛋白损伤血管内皮细胞保护作用的研究

目的:研究三七皂苷(PNS)对氧化低密度脂蛋白(Ox-LDL)损伤血管内皮细胞的保护作用。方法:体外培养人脐静脉内皮细胞(HUVEC),加入100mg·L-1Ox-LDL造成细胞损伤,同时加入不同浓度PNS进行干预。观察形态学变化;采用MTT法测定细胞活性;比色法检测细胞上清液中乳酸脱氢酶(LDH)的释放量;硝酸还原法和放射免疫法分别测定HUVEC培养上清液中一氧化氮(NO)、内皮素(ET)含量。结果:各剂量PNS可使作用Ox-LDL的HUVEC形态趋于正常。与正常对照组比较,HU-VEC经Ox-LDL作用后,细胞活性显著下降,LDH的释放量显著升高;300、100、30mg·L-1PNS显著升高细胞活性,抑制LDH释放。HUVEC经Ox-LDL作用后,与正常对照组比较,培养上清液中NO含量显著降低,ET含量显著升高;300、100mg·L-1PNS显著升高NO含量,300mg·L-1PNS显著降低ET含量。结论:PNS对Ox-LDL损伤的血管内皮细胞具有一定的保护作用,可调节内皮细胞活性物质NO、ET的分泌。