浙江地区幽门螺杆菌优势基因型研究

目的研究浙江地区幽门螺杆菌(Helicobacter pylori,Hp)的优势基因型并探讨各基因在不同胃十二指肠疾病患者中Hp的差异。方法从胃十二指肠疾病患者的胃粘膜活检组织中分离培养到Hp 129株,抽提基因组DNA后用PCR检测Hp的cagA、vacA、iceA及babA2等基因的分布,用卡方检验分析各基因在不同胃十二指肠疾病中Hp的差异。结果129株Hp中cagA的阳性率为99.2%(128/129),vacA sla基因型阳性率为94.6%(122/129),vacA m2为83.7%(108/129),iceA1为84.5%(109/129),iceA2为46.5%(60/129),babA2阳性率为81.4%(105/129)。消化性溃疡患者Hp的vacAm2基因阳性率高于慢性胃炎患者Hp(P<0.05),其余基因在不同类型疾病中的分布无统计学差异(P>0.05)。结论浙江地区Hp菌株的优势基因型为cagA,vacAsla/m2,iceAl,babA2;消化性溃疡患者Hp的vacAm2基因阳性率明显高于慢性胃炎患者。     

不同消化性疾病来源的Hp毒力基因检测与临床意义

目的研究不同消化性疾病来源的幽门螺杆菌(Hp)毒力基因的检测与意义。方法选择2016年10月-2017年10月于医院就诊的消化性疾病患者127例的胃活检样本,分离培养Hp,检测其携带的毒力基因,并探讨Hp与慢性萎缩性胃炎(Chronic Atrophic Gastritis,CAG)、慢性浅表性胃炎(Chronic Superficial Gastritis,CSG)、消化性溃疡(PUD)发生的关系。结果 127例不同消化性疾病患者Hp阳性率为42.52%(54/127);Hp共检测6种毒力基因(cagA、iceA、oipA、vacA、dupA、luxS)。Hp分离菌株中成功检出oipA、vacA及luxS,未发现vacA s2,其中vacA s1+阳性率100.00%;vacA m2+阳性率66.67%,vacA m1+阳性率31.48%,提示vacA m1+与vacA m2+关系互补;iceA1+/iceA2+、vacA s1 m1/iceA2对CSG的发生相关,vacA s1 m2+iceA2和iceA1+iceA2增加PUD发生风险,dupA+对十二指肠溃疡的发生相关。结论不同消化性疾病来源疾病(CAG、CSG、PUD)与Hp感染因素关系密切,加强感染Hp毒力基因检测可为以上消化性疾病预测评估、诊断等提供重要参考依据。     

不同类型慢性胃炎患者幽门螺杆菌的分离培养、耐药与毒力基因研究

目的 研究不同类型慢性胃炎患者幽门螺杆菌（Helicobacter pylori,Hp）的感染情况,检测分离株的耐药性与毒力基因。方法 采集患者胃黏膜,分离Hp并进行药敏试验。PCR扩增克拉霉素、左氧氟沙星耐药相关基因23S rRNA、gyrA及毒力基因cagA、vacA、iceA,测序并分析23S rRNA和gyrA扩增产物的突变位点。分析慢性胃炎类型与Hp的分离率、耐药性和毒力基因的关系。结果 120例患者共分离获得45株Hp（37.5%）。Hp对甲硝唑、克拉霉素、左氧氟沙星、阿莫西林、呋喃唑酮和四环素的耐药率分别为97.8%、28.9%、28.9%、4.4%、0和0。在克拉霉素和左氧氟沙星耐药菌株中,23S rRNA、gyrA基因最常见的突变位点分别为A2143G（76.9%）和N87K（38.5%）。cagA、vacA s1a、vacA s1b、vacA s1c、vacA s2、vacA m1、vacA m2、iceA1、iceA2阳性率分别为97.8%、97.8%、0、95.6%、0、37.7%、62.2%、71.1%、24.4%。在不同类型慢性胃炎组间,Hp的分离率差异有统计学意义（χ2 = 13.299,P＜0.05）,分离株的耐药率差异均无统计学意义（均P＞0.05）,iceA1、iceA2的分布差异有统计学意义（均P＜0.05）。结论 不同类型慢性胃炎患者Hp的分离率不同,Hp感染治疗可选呋喃唑酮和四环素,iceA1和iceA2毒力基因可能与胃炎类型有关。     

嘉兴地区幽门螺杆菌临床菌株cagA和vacA优势基因型研究

目的研究嘉兴地区幽门螺杆菌（Hdicobacter pylori，Hp）临床菌株cagA和vacA优势基因型状况及与疾病的关系。方法从胃、十二指肠疾病患者的胃粘膜活检组织中分离培养出44株HD。采用PCR检测cagA基因和vacA基因的信号区（s）和中间区（m）亚型的分布，用卡方检验分析各基因在不同消化性溃疡或慢性胃炎中的Hp差异。结果44株Hp中cagA的阳性率为100％（44／44），vacA sla／m2基因型阳性率为61．4％（27／44），vacA sla／mlb为25．0％（11／44），vaeA sla／mlb-m2为9．0％（4／44），其中有2株HD同时检出sla／m2和sh／mlb-m2基因，另有2株Hp未检测到m区基因。慢性胃炎患者Hp的vacA sla／m2和vacA sla／mlb基因阳性率赐显高于消化性溃疡患者的Hp（P〈0．05），其余基因在不同类型疾病中的分布无统计学差异（P〉0．05）。结论cagA＋vacA sla／m2、cagA＋vacA sla／mlb均为嘉兴地区消化性溃疡或慢性胃炎患者感染的Hp的优势基因型，部分患者可混合感染多株不同vacA基因型的HD。     

幽门螺杆菌的毒力基因、vacA基因亚型与上消化道疾病关系的研究

目的研究镇海地区幽门螺杆菌(Hp)尿素酶基因(ureA)、细胞毒素相关基因(cagA)、空泡细胞毒素基因(vacA)及vacA基因亚型与上消化道疾病之间的关系。方法用普通聚合酶链反应(PCR)技术,测定84株从上消化道疾病患者胃窦黏膜中分离获得的Hp的ureA基因、cagA基因、vacA基因、vacA基因亚型。结果84株Hp中,ureA、cagA、vacA基因的阳性率分别为100.00%、90.48%、95.24%,cagA、vacA在胃炎、消化性溃疡的阳性率高于胃癌(P<0.05);vacAm2基因的阳性率为79.76%,明显高于vacAm1a(20.24%)、vacAm1b(8.33%)及vacAm1bm2(4.76%),vacAm2在胃炎、消化性溃疡的阳性率高于胃癌(P<0.05),其余3个基因亚型阳性率差异均无统计学意义(均P>0.05)。结论镇海地区Hp相关性上消化道疾病患者感染Hp以ureA阳性、cagA阳性、vacAm2亚型占优势,且均在消化性溃疡及胃炎中的检出率更高。     

淮南地区矿工幽门螺杆菌vacA、cagA基因分布特征

[目的]研究淮南地区煤矿工人幽门螺杆菌(Helicobacterpylori,H.pylori)vacA、cagA基因分布特征。[方法]选择经胃镜及病理组织检查诊断证实有相关胃、十二指肠疾病的349名矿工为研究对象,取其胃窦部活检黏膜作H.pylori的分离培养,利用聚合酶链反应技术(PCR)测定分离培养出H.pylori菌株的vacA、cagA基因,并进行分型。[结果]349份样本中共分离培养出244株H.pylori菌株,其中慢性胃炎、萎缩性胃炎、胃溃疡及十二指肠溃疡幽门螺杆菌培养阳性率分别为61.61%(69/112)、61.54%(48/78)、75%(72/96)及87.30%(55/63);基因测定结果显示,244株H.pylori菌株临床分离株中,84.84%(207/244)含vacA基因,73.36%(179/244)含cagA基因;其中慢性胃炎、萎缩性胃炎、胃溃疡及十二指肠溃疡cagA、vacA基因检出率分别为66.67%(46/69)、50.72%(35/69)、85.42%(41/48)和70.83%(34/48)与93.06%(67/72)、84.72%(61/72)、96.36%(53/55)和89.09%(49/55),4种疾病间差异均具显著性(P<0.01)。进一步分型发现,慢性胃炎、萎缩性胃炎,胃溃疡及十二指肠溃疡患者中vacA 、cagA 分别为44.93%(31/69)、66.67%(32/48)、79.17%(57/72)、87.27%(48/55),差异具显著性(χ2=30.80,P<0.01)。vacA 、cagA 菌株主要多见于损害较严重的胃黏膜表面,如萎缩性炎症、炎性坏死等,23例腺体不典型增生的胃黏膜表面均为vacA 、cagA 菌株。[结论]淮南地区矿工H.pylori感染多为vacA 、cagA 菌株,vacA 、cagA H.pylori菌株为高毒力菌株,且与较严重的胃黏膜病理改变有关,可能是导致矿工慢性胃炎、消化性溃疡的重要因素,临床应充分重视H.pylori菌株毒力因子的监测。     

淮南地区学生幽门螺杆菌vacA和cagA基因分布特征

目的研究淮南地区学生幽门螺杆菌(Helicobacter pylori,H.pylori)cagA和vacA基因分布特征,为防治工作提供理论依据。方法对74例有消化道症状,年龄在7~24岁的在校学生进行胃镜检查,并在胃窦部取活检粘膜作H.pylori的分离培养,利用聚合酶链反应技术(PCR)测定分离培养出的H.pylori菌株的cagA和vacA基因并进行分型。结果74例学生中,分离培养出H.pylori菌株24例,基因测定结果显示,24株H.pylori临床分离株中,94.7%(23/24)含vacA基因,70.8%(17/24)含cagA基因;其中慢性胃炎vacA和cagA基因检出率分别为94.7%(18/19),70.6%(12/17);2例胃溃疡及3例十二指肠球部溃疡均全部为vacA和cagA阳性;进一步分型发现89.5%(17/19)的慢性胃炎为vacA 和cagA ,而5例溃疡患者均为vacA 和cagA 。结论淮南地区学生H.pylori感染多为vacA 和cagA 菌株,应充分重视H.pylori毒力因子的监测。     

幽门螺杆菌感染和基因型与儿童胃 十二指肠溃疡的相关性

目的分析儿童胃、十二指肠溃疡患儿幽门螺杆菌(Hp)的感染率和基因型(cagA、iceA、vacA、dupA、oipA及luxS)的检出率,探讨Hp基因型与儿童胃、十二指肠溃疡疾病的相关性。方法选择2016年8月-2020年2月在该院住院治疗的胃、十二指肠溃疡患儿320例,胃镜检查取胃黏膜活检,分离Hp进行培养,采用聚合酶链反应(PCR)和测序进行Hp基因型鉴定,检测Hp感染率和各基因及其组合在不同类型消化性溃疡患儿的检出率,并采用Logistic回归筛选诱发胃、十二指肠溃疡患儿的Hp基因型。结果320例胃、十二指肠溃疡患儿中共分离培养141株Hp(胃溃疡56例,十二指肠溃疡69例和胃、十二指肠复合溃疡16例),总体感染率为44.1%,3组间Hp感染率比较差异有统计学(P<0.05),且十二指肠溃疡感染率明显高于胃溃疡(χ²=5.778,P=0.016)和胃、十二指肠复合溃疡组(χ²=4.108,P=0.043);Hp基因型在胃溃疡、十二指肠溃疡及胃、十二指肠复合溃疡3组间的阳性检测率比较,差异无统计学意义(P>0.05);经二分类Logistic回归分析示,Hp感染中cagA、iceA1、VacA-s1、VacA-s1/m2、oipA及luxS基因型是儿童胃、十二指肠溃疡发生的危险基因型(P<0.05)。结论Hp基因型与儿童胃、十二指肠溃疡类型无相关性,cagA、iceA1、VacA-s1、VacA-s1/m2、oipA及luxS基因型可能是儿童胃、十二指肠溃疡危险因素,对于疾病的诊断及早期靶向治疗具有重要的意义。     

幽门螺杆菌中国菌株致病相关基因cagA、iceA、vacA及HP0519分布分析

目的分析中国不同人群及不同胃部疾病病例来源的幽门螺杆菌致病相关基因cagA、iceA、vacA及HP0519的分布.方法采用特异引物聚合酶链式反应（PCR）方法分析150株幽门螺杆菌上述基因的多态性分布特点,并对其分布作初步统计分析.结果93%（139/150）中国菌株cagA基因3′端重复序列的PCR产物具有东方菌株特征.75%（113/150）菌株iceA基因为iceA1,19%（29/150）为iceA2,不同地区间iceA基因的分布差异无统计学意义.云南菌株iceA1、iceA2的分布与菌株分离个体的种族特点及临床疾病类型无显著关系.96%中国菌株（144/150）vacA基因s区的等位基因为s1;m区等位基因m2、m1b和m1b-m2的比例分别为57%（85/150）、27%（41/150）和11%（16/150）,仅2株福建菌株为m1a.不同地区间vacA s1、m2、m1b分布的差异无统计学意义.云南菌株m1b-m2的分布高于福建和北京菌株.云南菌株vacA s区等位基因的多样性与分离个体的种族及临床疾病类型无显著关系.vacA m区等位基因的多样性与分离个体的临床疾病类型无显著关系,但不同民族间m2的分布有显著差异,白族人群m2的分布显著少于汉族和纳西族.93%（140/150）的中国菌株HP0519基因具有24 bp和15 bp DNA插入和缺失的多态性特点.不同地区间HP0519基因的多态性无显著不同.云南菌株HP0519的多态性与菌株分离个体的临床疾病类型无显著关系,但来源不同民族菌株的HP0519基因存在差异.结论幽门螺杆菌中国菌株cagA 3′端JF/TR特异引物的扩增结果具有东亚菌株特点.中国菌株vacA基因多为s1,其分布与菌株分离个体的临床疾病类型无关.中国菌株vacA基因m区的分布具有多样性.中国菌株HP0519基因具有24 bp和15 bp插入和缺失的多态性特点.     

浙江人群幽门螺杆菌cagA/vacA优势基因型和不同基因型混合感染的调查

目的　了解消化性溃疡和慢性胃炎患者感染的幽门螺杆菌 (Hp)cagA vacA优势基因型及不同基因型Hp感染、混合感染与疾病的关系。 方法　选择胃窦、胃体双份活检标本均培养出Hp的 42例慢性胃炎 (CG)和 3 6例消化性溃疡 (PU )患者作为研究对象 ,采用聚合酶链反应 (PCR)检测156份Hp分离株的cagA基因、vacA基因的信号区 (s)和中间区 (m )亚型 ,分析Hp基因型及多株Hp混合感染在CG和PU中的分布。结果　胃窦标本cagA基因的检测中 78例患者中有 75例 (96.2 % )为cagA阳性 ,相应的胃体标本中 ,76例患者 (97.4% )为cagA阳性 ,有 1例 (1.3 % )患者胃窦、胃体检出cagA状态不一的Hp混合菌株。在胃窦标本的vacA基因分型中 ,s1a m1、s1a m2、s1a m1b、s1a m1b m2 4种vacA基因型在 78例患者中所占比例分别为 6.4% (5 78)、55.1% (43 78)、2 6.9% (2 1 78)和 1.3 % (1 78) ,多株混合感染为 3 .8% (3 78) ;而相应的胃体标本中 ,前述四种vacA基因型所占比例依次为 6.4% (5 78)、53 .8% (42 78)、2 5.6% (2 0 78)和 3 .8% (3 78) ,多株混合感染为 5.1% (4 78)。cagA+ s1a m2和cagA+ s1a m1b在胃窦标本中占 51.3 % (40 78)和 2 6.9% (2 1 78) ,而在相应的胃体标本中占 52 .6% (41 78)和 2 5.6% (2 0 78)。少量胃窦、胃体     

Determination of cagA, vacA genotypes of Helicobacter pylori with real-time PCR-method

Presence of cagA gene of Helicobacter pylori (H. pylori) increases proliferation of stomach mucosa and it is an index of raised virulence of the bacteria. The vacA gene of H. pylori induces a serious inflammation of stomach. The purpose of this study was to determine cagA and vacA genotypes of H. pylori using real-time polymerase chain reaction (PCR) method with the double strain DNA-(dsDNA) binding SYBR Green I. dye. Results were compared with those of two immunohistochemical methods. 43 patients' paraffin embedded biopsy tissue samples were examined by histology, epidermal growth factor receptor (EGFR), proliferating cell nuclear antigen (PCNA) immunohistochemistry and melting curve analysis of real-time PCR using LightCycler instrument. Results of histology and real-time PCR from gastric biopsies correlated in 57% of cag acases and in 58% of vac cases. Significant difference was detected between normal and gastritis cases in the presence of cagA gene (p = 0.003) and between normal epithelial and intestinal metaplasia cases in the presence of vacA gene (p = 0.045) by investigation of association of histology and genotype of bacterium. Statistically significant difference (p = 0.02) was found between increased cell proliferation and the presence of gastritis. Significant correlation was found between the presence of cagA gene and EGFR expression in intestinal metaplasia cases (p = 0.0418). Results underlie the statistics that infection with cagA positive H. pylori strain increases the cell proliferation on the stomach mucosa and raises the chance of development of intestinal metaplasia. Infection with vacA positive H. pylori inhibits the signal-transduction pathway of EGFR, which influences mechanisms of mucosa repair. The role of EGFR and H. pylori infection is yet unclear in intestinal metaplasia and cancer. The authors' method seem to be suitable for determination of genotypes of H. pylori.     

Relation between Helicobacter pylori cagA status and risk of peptic ulcer disease

Although colonization with any Helicobacter pylori strain is associated with peptic ulcer, it is uncertain whether the risk is greater with cagA(+) or cagA(-) strains, which differ in their biology. A nested case-control study was done, based on a cohort of 5,443 Japanese-American men examined on the Hawaiian island of Oahu from 1967 to 1970. A total of 150 men with gastric ulcer, 65 with duodenal ulcer, and 14 with both diseases were identified. The authors matched the 229 cases with 229 population controls and tested their serum for immunoglobulin G antibodies to H. pylori and immunoglobulin G antibodies to the cagA product of H. pylori using enzyme-linked immunosorbent assays. Persons with H. pylori positivity had an odds ratio of 4.0 (95% confidence interval (CI): 1.9, 8.5) for gastric ulcer and 2.5 (95% CI: 0.8, 7.4) for duodenal ulcer. For CagA positivity, the odds ratios were 1.4 (95% CI: 0.9, 2.4) for gastric ulcer and 2.6 (95% CI: 1.1, 5.8) for duodenal ulcer. Subjects who were seropositive for both H. pylori and CagA had an odds ratio of 4.4 (95% CI: 1.8, 10.5) for gastric ulcer and 5.8 (95% CI: 1.1, 30.0) for duodenal ulcer. The results suggest that colonization with a cag(+) H. pylori strain elevates the risk beyond that of a cag(-) H. pylori strain for both gastric and duodenal ulcers.     

PCR-RFLP typing of ureC from Helicobacter pylori isolated in Argentina from gastric biopsies before and after treatment with clarithromycin.

A clinical trial was conducted in Argentina to determine the efficacy of clarithromycin plus lansoprazole for the treatment of Helicobacter pylori in duodenal ulcers and non-ulcer dyspepsia. PCR-RFLP was conducted on an 820-bp amplified product of the ureC gene of H. pylori to determine the genetic heterogeneity of 83 pretreatment and 21 post-treatment isolates. Twelve different restriction patterns were observed when digested with Sau 3A or Hha I, resulting in 40 different RFLP types. Comparison of isolates before treatment to after treatment showed that 20 of 20 patients had the same RFLP type. In addition, the presence of the cytotoxin-associated gene (cagA) and the vacuolating gene (vacA) were determined. All pretreatment isolates were positive for vacA whereas 75% of the pretreatment isolates were positive for cagA. The results of this study indicate that a high degree of heterogeneity exists among H. pylori and that infection is not limited to a small number of RFLP types.     

A preliminary study on the genetic profile of cag pathogenicity-island and other virulent gene loci of Helicobacter pylori strains from Turkey.

Helicobacter pylori genetic diversity affects the function and antigenicity of virulence factors associated with the disease outcome. Gene profile was done to identify the distribution of gene loci within and outside the cag pathogenicity-island (PAI). H. pylori strains from 35 patients [21 gastritis, 14 peptic ulcer diseases (PUD)] were analyzed using PCR. The profile of the cag PAI was evaluated using primers spanning the 3' end, cagA, promoter region of the cagA, cagE, cagT, 5' end (LEC), extreme right end, plasticity region open reading frames (ORFs), oipA (Hp0638) and vacA alleles. We found few intact cag PAI in the strains examined. Deletions were found in LEC1 (9.5% versus 14.3%), LEC2 (4.8% versus 14.3%), cagT (33.3% versus 28.6%), cagE (28.6% versus 28.6%) and the promoter region of the cagA (19.0% versus 42.9%) of gastritis and PUD strains, respectively. The cagA gene was detectable in 57.1% of gastritis and 92.9% of PUD-associated strains. The cagRJ region also showed deletions for many of its genes. The oipA (Hp0638) gene was detected in 80.9% of gastritis and in 92.9% of PUD strains. The plasticity region ORFs JHP912 and JHP931 were predominant in PUD strains. The vacA-s1a-m1a genotype was predominant in PUD, while s2m2 in gastritis strains. This comprehensive analysis showed deletions in several genes within and outside the cag PAI. However, cagA, oipA, JHP912, JHP931 and vacA-s1a-m1a were more predominant in PUD strains than gastritis-associated strains, suggesting the importance of genetic diversity on the disease progression and clinical outcome.