一种新的HBeAg阴性慢性乙型肝炎病毒变异机制

Objective To investigate mutation patterns in core promoter(CP)region of hepatitis B virus(HBV).Methods HBV DNA was extracted from sera of patients with chronic HBV infection.The CP sequence was amplified by polymerase chain reaction(PCR)and cloned into pMD19 T vector.The positive clones were then sequenced.The sequences were compared with known HBV genome in GenBank to identify the mutation sites and patterns of patients with chronic HBV infection.Results There were 74 clones from 21 patients with chronic HBV infection which were sequenced.The sequence comparisons showed that there was a 234-nucleotide deletion in CP region of HBV genome in 54 clones and a 245-nucleotide deletion in one clone.These deletion regions included CP,HBeAg initiation codon and direct repeat sequence(DR)Ⅰ regions,which named CP deletion(CPD).A1585T replacement mutation was also found in HBV strain with CPD,which indicated that there was linkage between these two mutations.Conclusions A novel mechanism of HBeAg negative chronic hepatitis B is observed,which includes deletions of CP and HBeAg initiation codon.Meanwhile,a simple and useful PCR method is developed to detect CPD.     

AMP-18,一种新发现的胃黏膜保护因子

AMP-18是一种新发现的由胃腺体上皮细胞合成的小分子蛋白质,独特表达于胃黏膜,机体其他部位少见,胃癌组织中表达缺失．AMP-18 由185个氨基酸组成,除去N端信号肽(20个氨基酸)后大小约18 ku,第54-150个氨基酸组成高度保守的结构域(BRICHOS区域)承担主要的生理功能．AMP-18由胃腺体上皮细胞以胞吐的方式分泌到胃黏液中,他的合成和分泌与个体生长发育有关,并受福斯高林、吲哚美辛、地塞米松等药物的影响．目前发现 AMP-18的生理功能主要有促进胃黏膜上皮细胞的有丝分裂,促进细胞的迁徙,促胃肠黏膜损伤的修复,保持胃肠黏膜的完整等．     

慢性淋巴细胞白血病与淋巴瘤细胞白血病的临床鉴别分析

慢性淋巴细胞白血病是造血系统的原发恶性肿瘤.表现为外周白血病持续增高,分类以小淋巴细胞为主,晚期常伴贫血、血小板减沙,浅表淋巴结及肝脾肿大;而淋巴瘤侵犯血、骨髓致淋巴瘤细胞白血病时,亦可有上述表现,不仔细分析易致混淆.     

一种新的乙型肝炎病毒X基因变异方式

目的:证实乙型肝炎病毒(hepatitis B virus,HBV)X基因一种新的变异方式.方法:从HBV慢性感染患者血清中提取HBVDNA,扩增X基因序列,克隆入pMD19 T载体,选择阳性克隆进行DNA测序,与已知HBV基因相应序列比较该患者体内HBV基因变异位点以及变异形式.结果:从21例患者中共挑选74个克隆测序,测序结果提示54个克隆X基因下游大段缺失突变,长度达234 nt,位于1601-1834 nt处,另有1个克隆发生245 nt缺失突变.发生缺失变异的病毒株同时存在G/A1515C、G1518C和A1585T替换突变,这两种突变具有联动特征.缺失突变株HBx仅编码76 aa其第44和45位编码为LL,具有特异性.结论:观察到一种X蛋白变异方式,这种大段缺失突变导致X蛋白下游编码序列丢失,其为X因子还是X蛋白以及这种变异是否为常态形式尚需进一步研究.     

三叶因子1在乙醇诱导的大鼠急性胃黏膜损伤中的表达

背景:三叶因子具有胃黏膜保护作用,但其在乙醇诱导的大鼠胃黏膜损伤中黏膜保护作用的研究较少.目的:观察短期灌注不同浓度乙醇大鼠胃黏膜三叶因子(TFF)1的表达情况,探讨TFF1与胃黏膜保护的相关性.方法:采用不同浓度乙醇直接灌胃制备急性胃黏膜损伤大鼠模型,以0.9%NaCl溶液灌胃作为对照,分别在肉眼和光学显微镜下观察胃黏膜形态学变化并评估黏膜损伤指数(LI),逆转录聚合酶链反应(RT-PCR)检测大鼠胃黏膜TEF1 mRNA的表达.结果:40%、70%、100%乙醇灌胃2 h后大鼠胃黏膜LI分别为38.38±6.37、70.00±8.02和118.75±14.82,显著高于对照组(P均＜0.01).在40%乙醇和70%乙醇组大鼠胃黏膜中TFF1/β-actin光密度比值分别为1.27±0.10和1.07±0.13,显著高于对照组的0.93±0.10(P均＜0.01),100%乙醇组TFF1/β-actin光密度比值为0.68±0.09,显著低于对照组(P＜0.01).结论:胃黏膜损伤程度与乙醇浓度呈正相关,乙醇浓度越高,胃黏膜损伤越严重;一定程度的胃黏膜损伤TFF1 mRNA表达升高,严重胃黏膜损伤TFF1 mRNA表达反而下降.一定程度的损伤刺激能使TFF1产生胃黏膜保护作用.     

一种新的HBeAg阴性慢性乙型肝炎病毒变异机制

Objective To investigate mutation patterns in core promoter(CP)region of hepatitis B virus(HBV).Methods HBV DNA was extracted from sera of patients with chronic HBV infection.The CP sequence was amplified by polymerase chain reaction(PCR)and cloned into pMD19 T vector.The positive clones were then sequenced.The sequences were compared with known HBV genome in GenBank to identify the mutation sites and patterns of patients with chronic HBV infection.Results There were 74 clones from 21 patients with chronic HBV infection which were sequenced.The sequence comparisons showed that there was a 234-nucleotide deletion in CP region of HBV genome in 54 clones and a 245-nucleotide deletion in one clone.These deletion regions included CP,HBeAg initiation codon and direct repeat sequence(DR)Ⅰ regions,which named CP deletion(CPD).A1585T replacement mutation was also found in HBV strain with CPD,which indicated that there was linkage between these two mutations.Conclusions A novel mechanism of HBeAg negative chronic hepatitis B is observed,which includes deletions of CP and HBeAg initiation codon.Meanwhile,a simple and useful PCR method is developed to detect CPD.     

福辛普利和氨氯地平对高血压病患者血压和肾功能的影响

目的：探讨福辛普利和氨氯地平对高血压病患血压和肾功能的影响。方法：40例高血压病患随机被分成2组,福辛普利组（20例,10mg,1次／日）,氨氯地平组（20例,5mg,1次／日）;疗程24周,治疗前,后观察血压和肾功能变化。结果：（1）两组患治疗后动脉压及蛋白的排泄量均显降低;（2）福辛普利组尚能显提高肾小球滤过率（P＜0．05）。结论：福辛普利和氨氯地平均能有效降低高血压病虱的血压及尿蛋白排泄量。福辛普利还有保护肾功能的作用。     

一种新的HBeAg阴性慢性乙型肝炎病毒变异机制

Objective To investigate mutation patterns in core promoter(CP)region of hepatitis B virus(HBV).Methods HBV DNA was extracted from sera of patients with chronic HBV infection.The CP sequence was amplified by polymerase chain reaction(PCR)and cloned into pMD19 T vector.The positive clones were then sequenced.The sequences were compared with known HBV genome in GenBank to identify the mutation sites and patterns of patients with chronic HBV infection.Results There were 74 clones from 21 patients with chronic HBV infection which were sequenced.The sequence comparisons showed that there was a 234-nucleotide deletion in CP region of HBV genome in 54 clones and a 245-nucleotide deletion in one clone.These deletion regions included CP,HBeAg initiation codon and direct repeat sequence(DR)Ⅰ regions,which named CP deletion(CPD).A1585T replacement mutation was also found in HBV strain with CPD,which indicated that there was linkage between these two mutations.Conclusions A novel mechanism of HBeAg negative chronic hepatitis B is observed,which includes deletions of CP and HBeAg initiation codon.Meanwhile,a simple and useful PCR method is developed to detect CPD.     

三叶因子与胃黏膜保护的研究进展

三叶因子家族是一群主要由胃肠道黏液细胞分泌的小分子多肽.其共同特征为均含一特殊的P结构域及三叶状结构.这种稳定的结构使三叶因子家族具有明显的抗蛋白酶水解、酸消化及耐热特性,因而能在消化道复杂的环境中保持生物活性.目前在哺乳动物体内发现的有pS2/TFF1、SP/TFF2和ITF/TFF3三种,它们具有黏膜保护与修复、肿瘤抑制、信号传导、调节细胞凋亡等功能.本文阐述了三叶因子家族发现的历史,并初步探讨了其作用.同时也对三叶因子受体这一热点的研究现状进行总结.