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目的:检测镇江地区幽门螺杆菌(Helicobacterpylori,H pylori)尿素通道蛋白基因ureI,并进行克隆和序列分析.方法:从胃十二指肠疾病患者胃黏膜组织中分离培养获得60例H pylori,PCR扩增检测ureI基因,部分菌株的ureI基因克隆至pMD18-T载体上,进行测序和序列分析.结果:60例H pylori菌株的ureI检出率为100%,成功克隆了8株来源于慢性胃炎、消化性溃疡和胃癌的H pylori菌株ureI并进行了序列分析.结果表明不同来源H pylori菌株之间ureI核苷酸和氨基酸序列同源性均高达95.6%以上.结论:ureI基因在H pylori中高度保守,可以作为鉴定H pylori的分子诊断标志.  相似文献   

3.
目的: 研究幽门螺杆菌( H pylori) cagA、iceA基因及其不同组合对H pylori感染结局的影响, 探讨西安地区H pylori的优势致病基因型.方法: 用快速尿素酶试验(rapid urease test,RUT)筛选出H pylori阳性胃黏膜标本101例,细菌基因组DNA提取试剂盒提取DNA, 用聚合酶链反应(PCR)扩增尿素酶C( ureC)基因的方法筛选出H pylori阳性标本91例. 经PCR及琼脂糖凝胶电泳对cagA, iceA的基因亚型进行检测, 用χ2检验以及Fisher精确检验分析各基因及其不同组合与疾病的相关性.结果: cagA基因的阳性率为79.1%, iceA的总检出率为75.82%, 其中iceA1为50.5%, iceA2为38.5%, cagA+/ iceA1+的检出率高于其他组,单一基因及其不同组合在各疾病组中分布没有显著差异. iceA与cagA存在相关性. iceA2分别发现有229、334、439、549 bp以及229bp+334 bp的基因片段.结论: cagA+/ iceA1+是西安地区H pylori的优势致病基因型, cagA、iceA1、iceA2各单一基因以及其不同组合与感染的临床结局无关. iceA与cagA基因可能存在协同作用, 该地区iceA2基因有较大的变异性.  相似文献   

4.
目的:评估镇江地区H pylori临床株的cagA基因阳性率、了解菌株CagA蛋白的可能分型、其羧端可变区EPIYA的数目以及与临床结果之间有无关联.方法:培养分离来自临床胃十二指肠疾病患者的H pylori,提取基因组DNA,通过PCR方法检测H pylori cagA基因的状况.随机选择不同病种的cagA基因阳性(cagA )的PCR产物,通过转化质粒,进行cagA PCR产物测序,通过ExPASY-Tranlation软件获得cagA基因相应的CagA蛋白的氨基酸序列.国际标准株NCTC11637的cagA基因以及CagA蛋白序列通过搜索NCBI(www.ncbi.nlm.nih.gov)数据库获得.结果:60株H pylori临床株中,56例为cagA ,阳性率达93.3%.20例测序的结果表明,CagA蛋白结构可分为2种类型,19株东亚型和1株西方型.所有19株东亚型均为Yamaoka分型的A型,所有20例菌株的EPIYA的数目均为3个,与临床结果无关联.结论:cagA基因阳性率在不同病种之间无差异.镇江地区H pylori临床株的CagA蛋白的一级结构,与日本、韩国菌株一样,主要为东亚型,其CagA蛋白羧端可变区EPIYA数目均为3个,与临床结果无关联.  相似文献   

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目的:评估镇江地区H pylori临床株的cagA基因阳性率、了解菌株CagA蛋白的可能分型、其羧端可变区EPIYA的数目以及与临床结果之间有无关联.方法:培养分离来自临床胃十二指肠疾病患者的H pvlori,提取基因组DNA,通过PCR方法检测H pylori cagA基因的状况.随机选择不同病种的cagA基因阳性(cagA~ )的PCR产物.通过转化质粒,进行cagA~ PCR产物测序,通过ExPASY-Tranlation软件获得cagA基因相应的CagA蛋白的氨基酸序列.国际标准株NCTC11637的cagA基因以及CagA蛋白序列通过搜索NCBI(www.ncbi.nlm.nih.gov)数据库获得.结果:60株H pylori临床株中,56例为cagA~ ,阳性率达93.3%.20例测序的结果表明,CagA蛋白结构可分为2种类型,19株东亚型和1株西方型.所有19株东亚型均为Yamaoka分型的A型,所有20例菌株的EPIYA的数目均为3个,与临床结果无关联.结论:cagA基因阳性率在不同病种之间无差异.镇江地区H pylori临床株的CagA蛋白的一级结构,与日本、韩国菌株一样,主要为东亚型,其CagA蛋白羧端可变区EPIYA数目均为3个,与临床结果无关联.  相似文献   

6.
目的 幽门螺杆菌(Helicobacter pylori)热休克蛋白A亚单位的编码基因(hspA)克隆和序列分析,为H.pyiori基因工程疫苗的研究奠定基础。方法 应用PCR方法获得国内分离H.pylori菌株MEI,HP27和国际标准参考株H.pylori的hspA基因,通过定向克隆的方法分别插入克隆载体pNEB193中,用质粒酶切电泳和特异PCR方法鉴定重组质粒。克隆基因经测序后进行核苷酸和氨基酸的同源性比较。结果 重组质粒经双酶切后得到0.35kb的hspA基因片段,特异PCR可扩增出hspA基因片段,证实H.pylori hspA基因的重组克隆质粒构建成功。经测序,国内分离HpMEL-HP27的hspA基因全长357bp(Genbank收录号:AY295084),编码由118个氨基酸残基组成的肽链,hspA基因序列与GenBank公布的H.pylorl相应基因同源性高达95.20%~97.48%,氨基酸序列同源性在95.76%~97.46%之间。结论 克隆了H.pylori菌株MEL-HP27的hspA基因,其核酸序列与国际参考株NCTC11637同源性为97.48%。  相似文献   

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幽门螺杆菌尿素酶B亚单位编码基因的克隆与序列分析   总被引:2,自引:0,他引:2  
目的 幽门螺杆菌(Helicobacter pylori)尿素酶B亚单位的编码基因(ureB)的克隆和序列分析,为H.pylori基因工程疫苗的研究奠定基础。方法应用PCR方法获得国内分离H.pylori菌株MEI,HP27和国际标准参考株H.pylori的ureB基因,通过定向克隆的方法分别插入克隆载体pNEB193中,用质粒酶切电泳和特异PCR方法鉴定重组质粒。克隆基因经测序后进行核苷酸和氨基酸的同源性比较。结果 重组质粒经双酶切后得到1.71kb的ureB基因片段,特异PCR可扩增出ureB基因片段,证实H.pylori ureB基因的重组克隆质粒构建成功。经测序,国内分离H.pylori MEL-HP27的ureB基因全长1710bp( Genbank收录号:AY295085),编码由569个氨基酸残基组成的肽链,ureB基因序列与GenBank公布的H.pylori相应基因同源性高达96.08%~98.30%,氨基酸序列同源性在98.77%.99.82%之间。结论 成功克隆了MEL-HP27菌株的ureB基因,其核苷酸序列与国际参考株NCTC11637的同源性为97.67%。  相似文献   

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目的:探讨中国辽宁地区人群H pylori致病基因的疾病相关性,为揭示H pylori的致病机制及监测H pylori相关性胃疾病的高危人群提供线索.方法:选取胃黏膜活检标本491例,分组浅表性胃炎(GS)、萎缩性胃炎(GA)、溃疡(GU)、胃癌(GC),在微需氧的条件下,培养出H pylori 222例,并用标准的酚-氯仿方法提取菌种DNA后经聚合酶链反应及琼脂糖凝胶电泳对cagA,vacA,iceA基因亚型进行检测.同时取胃窦、体、角黏膜各1块,经石蜡切片,HE染色,行组织病理学诊断.结果:GA组感染m2(43.1%)亚型菌株构成比最高,与GU(18.2%)和GC(17.9%)组相比差异有统计学意义(P=0.015,P=0.020),与GS(30.00%)组相比差异没有统计学意义(P= 0.084).在GA组中,感染s1m2亚型菌株有22例(44.9%),与本组病例中其他基因亚型相比差别均有统计学意义,与Gu、GC组感染s1m2亚型菌株相比差别有统计学意义(P=0.039),与GS组相比差别没有统计学意义(P=0.067).结论:中国辽宁地区人群感染s1m2型菌株与萎缩性胃炎发生有关.  相似文献   

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体内外研究发现,幽门螺杆菌(H.pylori)感染可促进胃黏膜上皮细胞增殖或触发细胞凋亡,从而引起细胞动力学改变,而菌株的差异可导致不同的结果。目的:通过体外实验观察不同疾病来源的H.pylori菌株对人胃癌细胞株AGS的细胞活力、细胞凋亡和细胞周期的影响,以确定不同疾病来源H.pylori菌株的细胞毒性是否存在差异。方法:采用聚合酶链反应(PCR)鉴定分离自胃癌和胃炎患者的H.pylori菌株的毒力基因和相关亚型。将AGS细胞分别与H.pylori菌株共培养,采用四唑蓝(MTT)比色法检测细胞活力,流式细胞仪检测细胞凋亡和细胞周期。结果:cagA、uacA、iceA和babA2基因和相关亚型在胃癌和胃炎H.pylori菌株中呈均匀分布。不同菌株抑制AGS细胞活力和促进细胞凋亡的能力虽有强弱差别,但胃癌菌株与胃炎菌株之间不存在整体上的差别。多数H.pylori菌株能抑制AGS细胞周期的G1/S期转换。结论:不同H.pytori菌株对共培养的AGS细胞动力学的影响存在差异,但胃癌菌株与胃炎菌株的细胞毒性无整体上的差别。  相似文献   

10.
目的分析我国不同地区幽门螺杆菌(H.pylori)的CagA羧基端可变区特征,比较CagA可变区序列差异。方法选取分离自西安、浙江、云南地区的41株H.pylori,PCR扩增CagA羧基端可变区。测序后使用Primer Premier 5软件将核苷酸序列翻译为氨基酸序列,使用Vector NTI Suit6软件将所有菌株的CagA羧基端可变区氨基酸序列进行比较分析。结果41株菌的CagA氨基酸序列可分为东亚型和西方型两类:38株分离株为东亚型模式,其中有31株为典型东亚型,7株为变异东亚型;1株分离株为典型的西方型模式,2株表现为片段缺失的变异西方型。结论中国不同地区H.pylori的CagA蛋白序列以东亚型模式为主,占92.7%(38/41);但在至少2个地区的菌株中发现有2株和1株菌CagA羧基端可变区为西方型模式。  相似文献   

11.
AIM: Helicobacter pylori (H pylori ) has been linked to chronic gastritis, peptic ulcer, gastric cancer and MALT-lymphoma. The link of genotypes of H pylori to gastric cancer remains controversial. The aim of this study was to investigate the H pylori vacA alleles, cagA and iceA in patients with gastric cancer in Taiwan. METHODS: Patients with gastric cancer, peptic ulcer and chronic gastritis were enrolled in this study. We obtained biopsy specimens from the stomach at least 2 cm away from the tumor margin in patients with gastric cancer, and from the antrum of stomach in patients with peptic ulcer or chronic gastritis. DNA extraction and polymerase chain reaction were used to detect the presence or absence of cagA and to assess the polymorphism of vacA and iceA. RESULTS: A total of 168 patients (gastric ulcer: 77, duodenal ulcer: 66, and chronic gastritis: 25) were found to have positive PCR results of the biopsy specimens from patients with peptic ulcer and chronic gastritis. We found positive cagA (139/168, 83%), m2 (84/168, 50%) and iceA1 (125/168, 74%) strains in the majority of patients. In patients with gastric cancer, the vacA s1a and s1c subtypes were less commonly found than those in non-cancer patients (35/66 vs 127/168, P = 0.0001 for s1a and 13/66 vs 93/168, P<0.0001 for s1c). In the middle region, the m1T strain in patients with gastric cancer was more than that of non-cancer patients (23/66 vs 33/168, P = 0.02). CONCLUSION: In Taiwan, H pylori with positive vacA s1a, cagA and iceA1 strains are found in the majority of patients with gastric cancer or non-cancer patients. In patients with gastric cancer, the vacA s1a and s1c subtypes are less and m1T is more than in patients with peptic ulcer and chronic gastritis.  相似文献   

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AIM:Helicobacter pylori(Hpylori)has been linked to chronicgastritis,peptic ulcer,gastric cancer and MALT-lymphoma.The link of genotypes of Hpylorito gastric cancer remainscontroversial.The aim of this study was to investigate theHpylori vacA alleles,cagA and iceA in patients with gastriccancer in Taiwan.METHODS:Patients with gastric cancer,peptic ulcer andchronic gastritis were enrolled in this study.We obtainedbiopsy specimens from the stomach at least 2 cm awayfrom the tumor margin in patients with gastric cancer,andfrom the antrum of stomach in patients with peptic ulceror chronic gastritis.DNA extraction and polymerase chainreaction were used to detect the presence or absence ofcagA and to assess the polymorphism of vacA and iceA.RESULTS:A total of 168 patients(gastric ulcer:77,duodenalulcer:66,and chronic gastritis:25)were found to havepositive PCR results of the biopsy specimens from patientswith peptic ulcer and chronic gastritis.We found positivecagA(139/168,83%),m2(84/168,50%)and iceA1(125/168,74%)strains in the majority of patients.In patients withgastric cancer,the vacA sla and slc subtypes were lesscommonly found than those in non-cancer patients(35/66 vs127/168,P=0.0001 for sla and 13/66 vs93/168,P<0.0001for slc).In the middle region,the ml T strain in patientswith gastric cancer was more than that of non-cancer patients(23/66 vs33/168,P=0.02).CONCLUSION:In Taiwan,Hpyloriwith positive vacA sla,cagA and iceAl strains are found in the majority of patientswith gastric cancer or non-cancer patients.In patients withgastric cancer,the vacA sla and slc subtypes are lessand mlT is more than in patients with peptic ulcer andchronic gastritis.  相似文献   

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BACKGROUND: A novel Helicobacter pylori gene, iceA, has two allelic variants, and the iceA1 strain is associated with peptic ulcer disease. The aims of this study were to evaluate whether the possession of iceA1 gene is associated with gastric cancer or the severity of gastritis. METHODS: Ninety-seven subjects (46 patients with early gastric cancer and 51 control subjects) infected with H. pylori were studied. DNA was extracted from isolated H. pylori strains, and the presence of the iceA1 gene was examined by polymerase chain reaction. The features of gastritis were graded in accordance with the updated Sydney System, using gastric biopsy specimens. RESULTS: iceA1 was found in 61% of patients with gastric cancer and 53% of control subjects (NS). The grade of gastritis in iceA1-positive and -negative gastric mucosa was compared. Higher polymorphonuclear cell infiltration was observed in iceA1-positive subjects (P < 0.05). However, no significant difference was observed in the grades of mononuclear cell infiltration, glandular atrophy, and H. pylori density. CONCLUSIONS: Our results suggest that the iceA1 gene is not associated with the development of gastric cancer in Japan, whereas the iceA1-positive strain may induce more enhanced active gastric inflammation in cagA-positive and vacA s1/m1 strains.  相似文献   

14.
Background: A novel Helicobacter pylori gene, iceA, has two allelic variants, and the iceA1 strain is associated with peptic ulcer disease. The aims of this study were to evaluate whether the possession of iceA1 gene is associated with gastric cancer or the severity of gastritis. Methods: Ninety-seven subjects (46 patients with early gastric cancer and 51 control subjects) infected with H. pylori were studied. DNA was extracted from isolated H. pylori strains, and the presence of the iceA1 gene was examined by polymerase chain reaction. The features of gastritis were graded in accordance with the updated Sydney System, using gastric biopsy specimens. Results: iceA1 was found in 61% of patients with gastric cancer and 53% of control subjects (NS). The grade of gastritis in iceA1-positive and -negative gastric mucosa was compared. Higher polymorphonuclear cell infiltration was observed in iceA1-positive subjects (P &lt; 0.05). However, no significant difference was observed in the grades of mononuclear cell infiltration, glandular atrophy, and H. pylori density. Conclusions: Our results suggest that the iceA1 gene is not associated with the development of gastric cancer in Japan, whereas the iceA1-positive strain may induce more enhanced active gastric inflammation in cagA-positive and vacA s1/m1 strains.  相似文献   

15.
胃癌,消化性溃疡患者幽门螺杆菌和iceA基因的研究   总被引:2,自引:0,他引:2  
目的研究幽门螺杆菌(Hp)的iceA基因与胃癌、消化性溃疡病的关系。从121例患不同胃十二指肠疾病的患者胃活检组织中分离培养Hp,PCR扩增检测Hp的cagA和iceA基因。结果胃癌、消化性溃疡及功能性消化不良患者Hp的cagA基因的阳性率分别为:912%、871%和897%(P>0.05);而iceA1基因的阳性率分别为:680%、710%和692%(P>0.05)。结论我们的研究表明Hp的cagA和iceA1基因与胃癌及消化性溃疡的发生不相关。  相似文献   

16.
BACKGROUND: Helicobacter pylori causes chronic gastritis, peptic ulcer, gastric cancer and mucosa-associated lymphoid tissue (MALT) lymphoma. Different genotypes of H. pylori are confirmed from diverse geographical areas. Its association with clinical diseases remains controversial. The aim of the present study was to investigate the H. pylori vacuolating cytotoxin (vacA) alleles, cytotoxin-associated gene (cagA) and iceA, in patients with peptic ulcer and gastritis. METHODS: We enrolled patients with peptic ulcer and chronic gastritis. Biopsy specimens were obtained from the antrum and lower body of the stomach. DNA extraction and polymerase chain reaction (PCR) were used to detect the presence or absence of cagA and to assess the polymorphism of vacA and iceA. RESULTS: A total of 133 patients (57 gastric ulcer, 52 duodenal ulcer, 24 chronic gastritis) had positive PCR results from biopsy specimens. Concerning genotypes, we found cagA (79% in the antrum, 92% in the body) and iceA1 (73% in the antrum, 82.8% in the body) strains in the majority of patients. The dominant vacA subtype was s1a (74.4% in the antrum, 75% in the body), followed by s1c (51.1% in the antrum, 60.5% in the body). In the middle region, the m2 strain dominated (49.6% in the antrum, 41.4% in the body), followed by m1T (19.5% in the antrum, 9.5% in the body). Mixed infection occurred in 89 patients (67%). There was no statistical difference in genotypes among the three groups. CONCLUSION: In Taiwan, H. pylori with positive cagA and iceA1 was found in the majority of cases. H. pylori with vacA s1a strains was the most common vacA subtype, followed by s1c, while s1b was rare. In the middle region, the m2 subtype was predominant followed by m1T. There was no significant association between genotypes and clinical diseases.  相似文献   

17.
Genotypes of Helicobacter pylori in patients with peptic ulcer bleeding   总被引:1,自引:0,他引:1  
AIM: Helicobacter pylori causes chronic gastritis, peptic ulcer, gastric cancer and MALT-lymphoma. Different genotypes of Helicobacter pylori are confirmed from diverse geographic areas. Its association with bleeding peptic ulcer remains controversial. The aim of this study was to investigate the Helicobacter pylori vacA alleles, cagA and iceA in patients with bleeding peptic ulcer. METHODS: We enrolled patients with bleeding, non-bleeding peptic ulcers and chronic gastritis. Biopsy specimens were obtained from the antrum of the stomach for rapid urease test, bacterial culture and PCR assay. DNA extraction and polymerase chain reaction were used to detect the presence or absence of cagA and to assess the polymorphism of vacA and iceA. RESULTS: A total of 168 patients (60.4%) (25 patients with chronic gastritis, 26 patients with bleeding gastric ulcer, 51 patients with non-bleeding gastric ulcer, 26 patients with bleeding duodenal ulcer, and 40 patients with non-bleeding duodenal ulcer) were found to have positive PCR results between January 2001 and December 2002. Concerning genotypes, we found cagA (139/278, 50%), vacA s1a (127/278, 45.7%), and ice A1 (125/278, 45%) predominated in all studied patients. In patients with bleeding peptic ulcers, vacA s1a and m1T were fewer than those in patients with non-bleeding peptic ulcers (37/106 vs 69/135, P=0.017, and 4/106 vs 21/135, P =0.002). CONCLUSION: In patients with peptic ulcers, H pylori vacA s1a and m1T prevent bleeding complication.  相似文献   

18.
OBJECTIVES: To investigate the prevalence of the vacA, cagA, cagE, iceA, and babA2 genotypes in Helicobacter pylori strains isolated from Thai dyspeptic patients, and to determine whether any correlation exists between these genotypes and clinical manifestations. METHODS: Helicobacter pylori was examined in 112 patients (62 with non-ulcer dyspepsia (gastritis), 34 with peptic ulcer disease, and 16 with gastric cancer (GCA)), detected by culture or direct detection from gastric biopsies. Allelic variants of the vacA, cagA, cagE, iceA, and babA2 genotypes were identified by using the polymerase chain reaction. RESULTS: The positive rates for the vacAs1, vacAs2, cagA, cagE, iceA1, iceA2, and babA2 genes in H. pylori of dyspeptic patients were 100%, 0%, 98.2%, 88.4%, 45.5%, 33.1%, and 92%, respectively. The allelic variant vacAs1m1 was more prevalent (58%) than vacAs1m2 (42%). The cagA and cagE genes were commonly found together (87.5%). The most predominant genotypes were vacAs1m1, cagA, cagE, iceA1, and babA2. The various genes alone or in combination had no statistically significant association with the clinical outcomes (p>0.05). CONCLUSION: Neither single gene nor combination of vacA, cagA, cagE, iceA, and babA2 genes was significantly helpful in predicting the clinical outcome of H. pylori infection in Thai patients. The high prevalence of these genes in H. pylori isolated from Thai patient groups suggests that H. pylori strains are geographically dependent.  相似文献   

19.
上海地区幽门螺杆菌菌株iceA、babA2基因型与临床的关系   总被引:7,自引:1,他引:7  
目的检测上海地区幽门螺杆菌(Hp)感染患者中Hp菌株iceA、babA2的分布特征,探讨与Hp临床感染结局相关的菌株基因型。方法141株Hp菌株分离自43例慢性胃炎(CG)、47例十二指肠球部溃疡(DU)、30例胃溃疡(GU)和21例非贲门部胃癌患者的胃镜活检标本。采用PCR方法检测Hp菌株的iceA、babA2、cagA和vacA基因型。结果141株Hp菌株中,iceA1、iceA2和babA2的总检出率分别为74.5%(105/141)、15.6%(22/141)和63.8%(90/141),其中2例(1.4%)为iceA1、iceA2均阳性,16例(11.3%)为iceA1、iceA2均阴性。DU组的babA2检出率显著高于GU组(74.5%比50.0%。P=0.028),DU组的cagA^ /babA2^ 检出率亦显著高于GU组(70.2%比46.7%,P=0.039)。其余疾病组之间的babA2检出率差异无显著性。未发现不同临床疾病与iceA基因型的相关性。结论上海地区Hp感染者的菌株基因型主要是iceA1^ /babA2^ ,babA2在DU和GU的发病机制中起不同作用。未发现iceA亚型与Hp临床感染结局有相关性。  相似文献   

20.
Helicobacter pylori is an important human pathogen associated with gastrointestinal diseases such as gastritis, gastric and duodenal ulcer (peptic ulcer disease, PUD), and gastric cancer. A number of pathogenic factors have been described for this bacterium, and some of them have been proposed as markers for the prediction of the clinical outcome. However, with the exception of the cag and vacA status, there is no universal consensus regarding the importance of the other virulence factors. Therefore, the aim of this study was to investigate the status of H. pylori strains regarding the babA and iceA alleles, as well as the cagA genotype, to reveal any association between these genotypes and clinical outcomes in Brazilian patients. The great majority (92.6%) of the strains were typed as iceA1, while 40.4% were found to possess the babA2 allele. The cagA gene was detected in 73.4% of the strains. The iceA2 and cagA genotypes were associated with PUD, while iceA1 was negatively correlated with PUD. However, considering the high percentage of strains typed as iceA1, these associations must be treated with caution. No clinical entity was associated with the babA2 allele. These results suggest that iceA1 is not a good marker for the diseases associated with H. pylori infection in Brazil. Further studies are needed in order to elucidate the relevance of the babA status, because other studies performed in Brazil have associated the babA2 allele with clinical outcomes. These results also indicate the existence of regional differences in the H. pylori genotypes and their association with clinical outcomes.  相似文献   

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