新型液相色谱-串联质谱法快速测定水产品中孔雀石绿及其隐色代谢物残留

目的采用液相色谱-串联质谱（LCMS／MS）建立水产品中孔雀石绿及其隐色代谢物残留的检测方法。方法均质后的水产品样品，用乙腈和乙酸铵缓冲液提取，合并提取液，用二氯甲烷反提取，经中性氧化铝柱和丙磺酸（PRS）柱固相萃取净化，没有使用氧化铅柱在线氧化，色谱分离后直接进入串联质谱检测器。采用电喷雾（ESI）正离子扫描模式，多反应监控（MRM）方式检测，外标法定量。结果孔雀石绿和隐色孔雀石绿的检出限为0．5ng／g，线性方程的相关系数r〉0．99，在添加浓度0．5～2．0ng／g范围内，孔雀石绿回收率为78．4％～92．1％。隐色孔雀石绿回收率为82．4％～98．1％，相对标准偏差（RSD）均小于5．7％。结论此方法高效快速，结果准确，重现性好，适合于对水产品中孔雀石绿和隐色孔雀石绿的残留检测。     

绿色荧光蛋白和酪氨酸羟化酶在骨髓基质细胞中的表达

目的研究反转录病毒介导的绿色荧光蛋白(EGFP)基因和酪氨酸羟化酶(TH)基因在原代培养的骨髓基质细胞(bMSCs)中的表达情况。方法体外分离培养大鼠四肢骨的bMSCs,原代培养8~10 d后,同时利用含EGFP和TH基因的反转录病毒上清依次转染bMSCs并进行抗性筛选,7~10 d可得到稳定表达EGFP的bMSCs,在稳定转染EGFP后10 d进行TH病毒上清的转染,7~10 d可得到稳定表达TH和EGFP的bMSCs。结果原代培养bMSCs 3~4 d后生长至70%~80%汇合,病毒转染EGFP后第2天,细胞呈现弱荧光,经G418筛选2~3 d后出现阳性细胞,约8~10 d生长融合,阳性率60%~70%,第2~5代阳性细胞比率无明显变化。TH阳性率也达60%以上。结论利用反转录病毒载体可有效地将EGFP和TH基因转至bMSCs中,并能在体外稳定表达传代。这种表达EGFP和TH的bMSCs对于研究bMSCs的体内迁移分化及帕金森病(PD)的基因治疗具有重要意义。     

环境镉离子生物检测工程菌株的构建及应用

目的 以绿色荧光蛋白（GFP）基因为报告基因，和重金属镉特异性启动子PcadA构建成基因工程重组体，用于重金属镉的特异性检测。方法 采用聚合酶链（PCR）方法从质粒pPcadA上扩增得到重金属镉离子特异性诱导启动子PcadA，以绿色荧光蛋白基因为报告基因，以大肠埃希菌．枯草杆菌穿梭载体pNW33N构建了绿色荧光蛋白镉离子诱导表达载体。以枯草芽孢杆菌1A751为宿主菌，采用感受态转化法将表达载体导入1A751，成功构建镉离子检测菌株。结果 通过酶切鉴定、PCR和DNA序列分析，重组载体构建成功，并在有镉离子存在的环境中得到表达。结论 该工程菌株能够以绿色荧光蛋白基因为报告基因检测培养体系中最低浓度达0．1μmol／L的镉离子；利用该菌株有望建立起一种方便快捷的重金属镉的检测方法，有较高的应用价值。     

四川省2005年霍乱分子流行病学特征

目的：分析四川省2005年霍乱弧菌分子特征,以及霍乱暴发疫情分离的菌株与菌株之间,疫情分离的菌株与海、水产品监测分离的霍乱弧菌之间的遗传相关性,查找霍乱传染来源,为预测疫情和制定防治措施提供依据.方法：利用聚合酶链反应（PCR）检测O139群霍乱弧菌特异性编码脂多糖基因（LPS）和霍乱毒力基因（ctxAB）;脉冲场凝胶电泳对菌株进行分子分型,所得结果以BioNumerics V4.0软件UPGMA方法进行聚类分析.结果：所试16株霍乱弧菌14株LPS阳性,为O139群霍乱弧菌;另2株为O1群稻叶型霍乱弧菌.2株稻叶型霍乱弧菌和1株O139群霍乱弧菌ctxAB阴性,其余13株菌均具有ctxAB,为产毒株.对16株菌以NotⅠ酶切后PFGE可分为5个型别.O139群霍乱弧菌优势流行株与从甲鱼分离的O139群霍乱弧菌PFGE型别一致,且同为产毒株.结论：甲鱼等海、水产品被O139群霍乱弧菌污染情况严重,甲鱼中分离的O139群霍乱弧菌与霍乱疫情分离菌株之间高度同源,被污染的甲鱼可能是本年度食源性霍乱暴发的主要传染来源之一,海、水产品的监测是近期霍乱防控的重点.     

荧光素眼底血管造影和吲哚青绿血管造影临床分析

目的了解与循环系统相关眼底病的发病率、年龄增长趋势以及血管造影检查在眼底病诊断中的应用价值.方法对眼科1283例患者进行荧光素眼底血管造影(fundus fluorescein abgiography,FFA)和/或吲哚青绿血管造影检查的资料、眼底病发病部位和性质进行了分组比较.结果在1283例患者中,视网膜血管性疾病700例,占54.5%,平均年龄58.7岁;黄斑部疾病330例,占25.7%,平均年龄54.1岁;炎性眼底病103例,占8%,平均年龄44.02岁.结论随着年龄增长,循环系统疾病的不断增多,眼底病发病率逐渐增高;应用彩色荧光吲哚青绿血管造影有助于眼与全身病的早期确诊和随访.     

Targeting events in melanoma carcinogenesis for the prevention of melanoma

Melanoma is one of the few tumors that have increased in incidence over the last few decades. Strategies devoted solely to protecting against ultraviolet radiation have, at best, had a modest impact on the development of melanoma. Chemoprevention is an under-explored approach that could significantly decrease the morbidity and mortality from this deadly cancer. However, the scientific and logistical challenges of performing clinical studies in chemoprevention require innovative approaches to prove the effectiveness of putative preventive agents. There are several pharmacological and nutriceutical agents that are mechanistically linked to events in melanoma carcinogenesis that are candidates for advanced human studies. We will review the data for several promising agents, including statins, curcumin, resveratrol, silymarin and green tea, and discuss some importance issues and concepts that should be considered in any melanoma chemoprevention strategy.     

息肉样脉络膜血管病变的分类与视力改变

目的 了解不同类型息肉样脉络膜血管病变(PCV)患者视力改变情况.方法 收集经眼底彩色照相、荧光素眼底血管造影、吲哚青绿血管造影(ICGA)以及光相干断层扫描检查确诊的67例PCV患者68只眼的临床资料.根据PCV的活动性与病理特征分为静止性、渗出性和出血性PCV;根据ICGA检查中息肉样病灶的形态特征以及是否合并分支状脉络膜血管网(BVN)分为葡萄状病灶型、单个病灶型和合并BVN的混合病灶型PCV;根据息肉样病灶分布部位分为黄斑区、血管弓区、视盘旁区、中周部和混合区PCV.观察各组的视力情况.结果 静止性、渗出性、少量出血性、多量出血性PCV分别有16、19、19、14只眼,其平均最小分辨角对数(logMAR)视力分别为0.34±0.52、0.70±0.98、0.60±0.50、0.91±0.75.静止性PCV患眼平均视力显著优于渗出性、少量出血性与多量出血性PCV患眼,组间比较,差异有统计学意义(q＝4.75、4.26、5.13,P＜0.05).渗出性PCV与少量出血性PCV患眼平均视力比较,差异没有统计学意义(q=0.98,P＞0.05).葡萄状病灶型、单个病灶或多处单个病灶型、合并BVN的混合病灶型PCV分别有22、38、8只眼,其平均logMAR视力分别为0.52±0.55、0.59±0.43、0.80±0.95.伴有BVN的混合病灶型PCV患眼平均视力显著差于葡萄状病灶型和单个病灶或多处单个病灶型PCV患眼,组间比较,差异有统计学意义(q=3.81、3.02,P＜0.05).黄斑区、血管弓区、视盘旁区、混合区PCV分别有34、1 3、8、13只眼,其平均logMAR视力分别为0.78±0.43、0.57±0.37、0.38±0.27、0.74±0.41.黄斑区PCV患眼平均视力差于血管弓区与视盘旁区PCV患眼,组间比较,差异有统计学意义(q=4.61、5.11,P＜0.05);黄斑区PCV与混合区PCV患眼平均视力比较,差异无统计学意义(q=0.73,P＞0.05).结论 PCV患者视力改变情况不一,且与PCV的活动性与病理特征、息肉样病灶的形态特征和分布部位以及是否合并BVN有关.     

Indocyanine green retention is a potential prog-nostic indicator after splenectomy and pericar-dial devascularization for cirrhotic patients

BACKGROUND: Splenectomy and pericardial devasculariza-tion (SPD) is an effective treatment of upper gastrointestinal bleeding and hypersplenism in cirrhotic patients with portal hypertension. Indocyanine green retention at 15 minutes (ICGR15) was reported to offer better sensitivity and speciifc-ity than the Child-Pugh classiifcation in hepatectomy, but few reports describe ICGR15 in SPD. The present study was to evaluate the prognostic value of ICGR15 for cirrhotic patients with portal hypertension who underwent SPD.
METHODS: From January 2012 to January 2015, 43 patients with portal hypertension and hypersplenism caused by liver cirrhosis were admitted in our center and received SPD. The ICGR15, Child-Pugh classiifcation, model for end-stage liver disease (MELD) score, and perioperative characteristics were analyzed retrospectively.
RESULTS: Preoperative liver function assessment revealed that 34 patients were Child-Pugh class A with ICGR15 of 13.6%-43.0% and MELD score of 7-20; 8 patients were class B with ICGR15 of 22.8%-40.7% and MELD score of 7-17; 1 patient was class C with ICGR15 of 39.7% and MELD score of 22. The optimal ICGR15 threshold for liver function com-pensation was 31.2%, which offered a sensitivity of 68.4% and a speciifcity of 70.8%. Univariate analysis showed preopera-tive ICGR15, MELD score, surgical procedure, intraoperative blood loss, and autologous blood transfusion were signiifcant-ly different between postoperative liver function compensated and decompensated groups. Multivariate regression analysis revealed that ICGR15 was an independent risk factor of post-operative liver function recovery (P=0.020).
CONCLUSIONS: ICGR15 has outperformed the Child-Pugh classiifcation for assessing liver function in cirrhotic patients with portal hypertension. ICGR15 may be a suitable prognos-tic indicator for cirrhotic patients after SPD.     

Bone marrow genotoxicity of 2,5‐dimethylfuran,a green biofuel candidate

2,5‐Dimethylfuran (DMF) is being considered as a potential green transportation biofuel, but there is limited information about its toxicity and safety. We examined DMF toxicity in the bone marrow using a murine in vitro erythropoietic micronucleus assay and found that exposure to DMF (0.1 mM, 1 hr) induced an increase in micronuclei frequency compared with controls. These data suggest that DMF may be genotoxic to hematopoietic cells and that more thorough toxicological studies on DMF should be conducted to ensure public and occupational safety before it is considered a viable biofuel and produced in mass quantities. As well as specific data on DMF, our study further validates an in vitro cell culture system that captures the essential features of the in vivo mammalian micronucleus genotoxicity assay, enabling increased throughput and controlled studies on hematopoietic DNA damage response, while reducing animal sacrifice. In vitro assays, such as the in vitro micronucleus assay, will be essential as international chemical policy is increasingly utilizing green chemistry principles that require more toxicological testing. Environ. Mol. Mutagen. 2012. © 2012 Wiley Periodicals, Inc.