High frequency somatic mutations in RASSF1A in nasopharyngeal carcinoma

High frequency loss of 3p21.3 region is a common event in various kinds of tumors including nasopharyngeal carcinoma (NPC). RASSF1A has been identified as a putative tumor suppressor gene residing in this region. Chromosome alterations and epigenetic changes are commonly observed as mechanisms for inactivation of RASSF1A function. In this study, we applied the PCR-cloning-sequencing strategy to examine somatic mutations in RASSF1A in NPC tissues as compared with the sequences detected in the matched peripheral blood lymphocytes. Our results revealed a high incidence of RASSF1A mutation in primary tumor tissues of NPC. There are totally 35 mutations identified in 74% (17/23) of these NPC cases, including 30 transitions, three transversions and two deletions. Most of these mutations result in amino acid changes: three nonsense (stop codon) mutations, two-1 bp deletion (frameshift), 26 missense and the remaining four are synonymous (silent). No obvious 'hot-spot' mutations were observed in this study. A similarly high rate (74%) of promoter methylation of RASSF1A was also detected in the same group of NPC tissues, but no significant correlation between mutation and methylation was detected. Our results suggest various mechanisms involved in inactivation of RASSF1A function and indicate a critical role of RASSF1A in NPC development.     

Nonylphenol and Nonylphenol Ethoxylates in River Water, Drinking Water,and Fish Tissues in the Area of Chongqing, China

Little attention has been paid to the estrogenic-like compounds, such as 4-nonylphenol (4-NP) and its potential precursor nonylphenol ethoxylates (NPEOs), in China although its usage is huge. Water samples and corresponding drinking water samples were seasonally collected at five sites of each of the two main rivers in Chongqing Area. Individual nonylphenol ethoxylates (NPEOs) and 4-NP in the Changjiang River and Jialingjiang River were detected by normal-phase liquid chromatography electrospray ionization mass spectrometry and gas chromatography-mass spectrometry. The results indicated that of the five sampling points in the two rivers, NPEOs were the dominant pollutant in April and December with the similar distribution profile, and total NPEOs with different ethylene oxide lengths were 6.9–97.6 g/L in April and 2.5–52.7 g/L in December. However, NP was the dominant pollutant in July with a concentration of 1.7–7.3 g/L. Corresponding drinking water samples derived from river water as source suggested that the conventional water treatment process used in the five waterworks could remove NPEOs from the source water with high removal efficiency (>99%). The 4-NP removal efficiency, however, varied in a range of 62% to 95%, leaving a significantly high concentration of NP (0.1 to 2.7 g/L) in drinking water in July. Fish samples taken in December 2000 contained 4-NP of 1.9g/g and NPEOs of 0.4–48.3g/g, with the highest concentration level found in liver.     

丙型肝炎病毒感染患者13～14年后病毒组织学随访观察

目的了解丙型肝炎病毒(HCV)感染后持续活动者的临床转归和肝脏组织学情况。方法5例因输血而感染丙型肝炎者,为女性,4例因单采血浆还输血球而感染丙型肝炎者,为男性,总共9例,所有感染者感染时间、感染途径清楚。采用炎症分级纤维化分期以及修正的Knodell评分对肝脏活检组织的炎症和纤维化程度进行评价,超声检查,血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)采用速率法,抗HCV采用酶联免疫吸附试验(ELISA)方法,HCVRNA定性检测采用RocheCobasHCV聚合酶链反应(PCR)试剂盒,HCVRNA定量采用BayerHCV分枝DNA(bDNA)试剂盒,HCVRNA基因型采用BayerLiPA基因型分析方法。结果(1)9例慢性丙型肝炎感染者共随访13～14年,其间于诊断时、1992、1995、1999、2003、2004年共检测6次ALT水平,均高于正常上限值(ULN)。(2)2004年检测9例慢性丙型肝炎感染者HCVRNA定性均为阳性,定量从3.57×108拷贝/L～7.21×109拷贝/L,大于2.00×109拷贝/L者5例。3例感染者为基因2型,其余6例为基因1b型。(3)9例慢性丙型肝炎感染者超声诊断为慢性炎症轻度者3例(3/9),占33.3%;中度6例(6/9),占66.7%;重度0例;脂肪肝1例(1/9),占11.1%。未发现失代偿性肝硬化和原发性肝癌。(4)9例慢性丙型肝炎感染者的肝组织炎症活动度(HAI)分数为5～8.5分,纤维     

我国人类免疫缺陷病毒-1主要流行株外膜蛋白基因V3-V4区及其临近区域的特征性氨基酸分析

目的鉴定我国HIV-1主要流行毒株亚型的env,V3-V4区及其临近区域的特征性氨基酸,并阐明其在追踪传染源和研究疫苗中的作用。方法应用nested—PCR对157份来自我国12个省份的HIV-1毒株env区序列进行扩增,并使用ABI377型测序仪测序,然后应用BLAST、GCG、MEGA和VESPA等生物学软件或程序对env基因V3-V4区及其临近区域序列进行基因型鉴定、系统树分析及特征性氨基酸鉴定。结果157份样本包括54份B′(34．40％)、61份B′／C(38．85％)和42份CRF01-AE(26．75％)毒株。系统树分析结果显示,B′亚型毒株序列均与B．CN．RL42十分接近,B′／C毒株主要与97CN54A和97CNGX6F聚成一簇。而CRF01—AE序列与THCM240和97CNGX2F聚在一起．而且分别聚成明显不同的两个亚组。特征性氨基酸分析发现,我国B′和B′／C毒株分别具有8个保守的特征性氨基酸,而且与代表株的相同位点氨基酸基本一致。而CRF01-AE重组毒株具有11个保守的特征性氨基酸,其中有9个位点与97CNGX2F和TH.CM240不一致。包括这9个特征性氨基酸的样本主要来自除云南省以外的其他省份。结论目前流行于我国的B′和B′／C毒株具有单一的共同传染源,而CRF01-AE毒株可能是通过不同输入源或不同传播途径先后从泰国传入我国的。这将对我国艾滋病防治策略的制定和正在进行的疫苗研究具有重要的指导意义。     

人黑皮素4受体F261S突变基因的克隆和功能验证

目的　研究黑皮素 4受体(MC_4R)基因的新突变F261S是否造成了MC4R蛋白功能改变。方法　用携带F261S纯合突变的先证者及正常人的基因组DNA,PCR扩增突变型及野生型MC4R基因全长,克隆到topo -TA真核表达质粒载体,测序鉴定后转染人胚肾 293细胞。用浓度为 1×10-11 ~1×10-5 mmol/L的α -黑色素细胞刺激素(α- MSH)与表达的MC4R蛋白结合后,用双荧光素酶报告基因测试系统检测胞内cAMP,萤火虫荧光 /海洋腔肠荧光二者强度之比体现了cAMP浓度。结果　α- MSH浓度在 1×10-9 ~1×10-8 mmol/L时野生型胞内双荧光强度比值显著高于突变型细胞(P<0 .05),在 1×10-7 ~1×10-5 mmol/L时差异更为显著 (P<0 .01)。结论　F261S突变使MC_4R介导的信号转导能力下降,此突变与中国人早发性肥胖有关。     

Platelet Functions in Cardiopulmonary Bypass Surgery

Background

Haemorrhage after Cardio Pulmonary Bypass (CPB) Surgery is a well recognised complication that leads to significant morbidity and mortality. The incidence varies between 5-25% depending upon the clinical situation. Several factors are implicated as causative but none have been precisely proved.

Methods

Our study was an attempt to evaluate the haemostatic defect with particular reference to platelet function abnormalities during cardio pulmonary bypass surgery, in order to reduce the morbidity and mortality associated with post CPB haemorrhage. Flow cytometric evaluation of different platelet glycoproteins like GPIb/IX, GPIIb/IIIa and GMP-140 was done.

Results

The marker expression showed deregulation during surgery which returned to base after bypass was terminated. In contrast, the cases with bleeding showed significant variation. P-Selectin (GMP 140) expression decreased progressively till 3^rd post-operative day showing lack of activation of platelets in cases of severe bleeding.

Conclusion

Longer duration of CPB initiates plasmin generation through heparin, which raises the PAI-1-tPA complex and thereby down regulating the functions of platelets. This suggests a link between duration of CPB, bleeding, platelet dysfunction and fibrinolysis. Hence serial estimations of the levels of GMP-140 and tPA can predict severe bleeding.Key Words: CardioPulmonary Bypass, Platelet dysfunction, flowcytometry, platelet glycoproteins, haemorrhage     

肝细胞癌肝移植89例预后分析

目的　总结肝细胞癌(HCC)肝移植临床经验,探讨HCC肝移植的预后影响因素。方法　应用单因素分析和逐步Logistic回归多因素分析方法,回顾性分析自1999年1月至2003年12月我单位施行的89例HCC肝移植患者的生存情况及各项临床病理指标对预后的影响。结果　移植后6个月、1年和2年累积生存率分别为81. 8%、55. 3%和43 .7%, 6个月、1年和2年无瘤生存率分别为62 .4%、35. 6%和24 .9%;随访期间肿瘤转移复发的总发生率为52 8%;Log rank检验结果显示,影响HCC患者肝移植术后累积生存率的因素为门静脉主干或分支癌栓形成(PVTT) (χ2 =15 14,P=0. 0001)、肿瘤大小(χ2 =15. 05,P=0 .0001 )、肝硬化背景(χ2 =6 14,P=0 .0132 )、术前甲胎蛋白(AFP)水平(χ2 =5 .82,P=0. 0159)和组织学分级(χ2 =4. 61,P=0 .0319);影响无瘤生存率的因素包括PVTT(χ2 =26 .30,P<0. 0001 )、肿瘤大小(χ2 =25 .25,P<0 0001 )、AFP水平(χ2 =14. 83,P=0 .0001)、组织学分级(χ2 =12 54,P=0. 0004 )、肿瘤分布(χ2 =12 73,P=0. 0004 )、肿瘤数目(χ2 =9 81,P=0 0017)以及肝硬化背景(χ2 =9 .76,P=0 .0018)。多因素分析结果显示,与累积生存率显著相关的因素是PVTT(RR=4. 721,P=0. 001 )、年龄(RR=3. 282,P=0 .007 )和组织学分级(RR=2. 368,P=0.     

The prophylactic and therapeutic effects of cholinolytics on perfluoroisobutylene inhalation induced acute lung injury

Perfluoroisobutylene (PFIB) is a kind of fluoro-olefin that is ten times more toxic than phosgene. The mechanisms of the acute lung injury (ALI) induced by PFIB inhalation remain unclear. To find possible pharmacological interventions, mice and rats were exposed to PFIB, and the prophylactic or therapeutic effects of 3-quinuclidinyl benzilate (QNB) and anisodamine were studied and confirmed. It was observed that the wet lung/body weight and the dry lung/body weight ratios at 24 h after PFIB exposure (130 mg/m(3) for 5 min) were significantly decreased when a single dose of QNB (5 mg/kg) was administered intraperitoneally either 30 min before exposure or 10 h after exposure. Anisodamine was without any prophylactic or therapeutic effects at single doses below 30 mg/kg. The effects of QNB against PFIB inhalation induced ALI were well evidenced by the significantly decreased mice mortality at 72 h, the total protein concentration in bronchoalveolar lavage fluid at 24 h after the PFIB exposure, as well as the ultrastructural observations. The analysis of the time courses of lung sulfhydryl concentration, myeloperoxidase (MPO) activity and hemorheology assay showed that the toxicity of PFIB may be due to consumption of lung protein sulfhydryl, influx of polymorphonuclear leukocytes (PMNs) into the lung, and increased peripheral blood viscosity at a low shear rate, all of which were partially blocked by QNB intervention except for PMN influx. The results suggest that cholinolytics might have prophylactic and therapeutic roles in PFIB inhalation induced ALI.