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。     

Effect of Helicobacter pylori infection, age and epithelial cell turnover in a general population at high risk for gastric cancer

BACKGROUND: H. pylori and age are two known risk factors for atrophic gastritis and high epithelial cell turnover may be an indicator for preneoplastic changes in the stomach. We searched for an association between H. pylori, age and gastritis in the general population together with the proliferative state into the antral mucosa. METHODS: We examined gastric biopsies from antrum and corpus of 117 consecutive volunteers which were endoscoped during a population study in San Marino. H. pylori status was determined by serum IgG antibodies, rapid urease test on biopsies and histology. Presence of gastritis and grading of inflammation, activity, intestinal metaplasia and atrophy were ascertained using Sydney System. On a subsample of 36 subjects without endoscopic lesions we performed an immunohistochemical study on gastric cell proliferation using PCNA. A computer-aided count was made on stained epithelial cells to evaluate labeling index. Statistical analysis was performed using chi 2 test and linear regression. RESULTS: Inflammatory infiltrate (both activity and mononuclear cells), (p < 0.0001) and intestinal metaplasia (p < 0.004) were significantly higher in H. pylori positive subjects. Atrophic gastritis was present in 82% H. pylori positive subjects vs 17.6% (p < 0.0001). Labeling Index was significantly higher in H. pylori positive subjects (p < 0.005) and it was correlated with inflammation and atrophy (p = 0.001). Elderly H. pylori negative subjects have a lower cell turnover (p = 0.006) but H. pylori infected subjects do not show any decrease of Labeling Index with age. CONCLUSIONS: In the general population of an area with high gastric cancer rate, H. pylori infection is associated with atrophic gastritis and with hyperproliferative gastric cell state. These conditions are present either in young and old age and increase the neoplastic risk of gastric mucosa.     

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。     

Effect of Helicobacter pylori infection and eradication on proliferative kinetics of the gastric mucosa

Helicobacter pylori infection is associated with an increased cell proliferation activity, however the exact mechanisms have not been elucidated. Our aim was to study the effect of Helicobacter pylori infection on normal gastric epithelia, gastritis, intestinal metaplasia and carcinoma by the expression of proliferating cell nuclear antigen and nucleolus organizer regions. Antral biopsies were taken from 121 patients (61 women, 60 men; mean age 58.5 y.). Sections were scored for normal epithelia (n = 15), gastritis without intestinal metaplasia (n = 74), gastritis with intestinal metaplasia (n = 24) and gastric carcinoma (n = 8). 52 patients had H. pylori positive gastritis, and success of eradication therapy was controlled in 34 cases. To characterize cell proliferation immunohistochemistry (PCNA) and histochemistry methods (AgNOR) were used. Results of PCNA and AgNOR significantly correlated except of that in the intestinal metaplasia group. PCNA LI and AgNOR counts were not significant higher in H. pylori positive compared to the H. pylori negative gastritis. Presence of H. pylori caused higher proliferation rate in intestinal metaplasia group measured by PCNA. In the group of intestinal metaplasia the proliferation activity decreased to the activity of the normal epithelia after the successful eradication, but remained high if eradication therapy was failed. Our results suggest, that H. pylori infection plays only as a co-factor in gastric carcinogenesis. Results were controversial in the intestinal metaplasia group, that can be explained by the heterogeneity of the bacteria.     

Gastric mucosal Helicobacter pylori distribution and its implications

In tile present study the clinicopathological aspects of H. pylori infection in different parts of the stomach were investigated in 36 patients. The results showed that 28 patients (77.8%) were H. pylori positive and 8 patients (22.2%) were H. pylori negative by histopathology and confirmation with modified Giemsa stain. There was no statistically significant difference belween H. pylori positive and negative patients regarding dyspeptic symptoms or intestinal metaplasia histopathologically. Histopathological examination revealed chronic gastritis with mononuclear cell infiltration in all studied patients. According to the degree of cell infiltration, chronic gastritis was graded as mild, moderate and severe. There was a statistically significant difference between H. pylori positive and H. pylori negative patients regarding both severity and activity of chronic gastritis in the antrum and body compared to the fundus. Also, there was significant correlation between the grade of H. pylori colonization and the grade of chronic active gastritis on one hand and between H. pylori infection and atrophic gastritis. The serum anti-H. Pylori - IgG positive cases who were H pylori negative by history, showed atrophic gastritis acid intestinal metaplasia. This may be due to the fact that the mucosa has become inhospitable for H. pylori.     

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     

肠上皮化生组织中CDX2表达及其与幽门螺杆菌感染的关系探讨

目的 探讨胃黏膜肠上皮化生组织中CDX2表达的临床意义及其与幽门螺杆菌(Hp)感染的关系.方法 采用免疫组织化学技术检测93例(其中正常胃黏膜7例,浅表性胃炎21例,萎缩性胃炎22例,萎缩性胃炎伴肠上皮化生43例)胃黏膜组织CDX2表达情况;使用14C尿素呼气试验检测Hp感染情况.结果 7例正常胃黏膜患者Hp检测阴性,Hp感染在萎缩性胃炎和萎缩性胃炎伴肠上皮化生中阳性率分别为77.27％(17/22)、65.12％( 28/43),显著高于浅表性胃炎的19.05％(4/21)(P＜0.0l).CDX2在正常胃黏膜及浅表性胃炎中无表达,在萎缩性胃炎伴肠上皮化生中阳性率83.72％( 36/43),显著高于萎缩性胃炎的40.91％(9/22)(P＜ 0.01).结论 Hp感染、CDX2表达与胃黏膜肠上皮化生有关,CDX2异常表达可能是启动胃黏膜上皮发生肠化的始动因素,检测胃黏膜组织中CDX2表达可以帮助临床识别胃黏膜肠上皮化生组织,预测胃癌前病变的进展,为临床选择治疗方案提供依据.     

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。     

Detection of Helicobacter pylori in tissue samples of stomach cancer]

The role of Helicobacter pylori in the carcinogenesis of the stomach has been recognised both in intestinal and diffuse forms. The occurrence of the bacterium was studied in this report, with various methods in biopsy samples from the cancerous stomach, as well as the presence of associated gastritis and metaplasia related to the histological type. Retrospective histological examination were performed on endoscopic biopsy samples from 124 patients with distal stomach cancer using haematoxillin-eosin and Giemsa staining and immunohistochemical tests. Out of the 124 samples 69 (55.64%) was positive: 48 with Giemsa staining and further 21 samples showed immunohistochemical positivity on atrophic gastritis samples despite negative Giemsa staining. In view of the presence of gastritis and metaplasia significant difference (p < 0.001) was found between the positive and negative cases. The ratio of the Helicobacter pylori positive samples was high both for intestinal and diffuse type carcinomas. Our results suggest that the presence of Helicobacter pylori infection is important in the development of both types of carcinoma, nevertheless, the hystological type of the tumor is also decisively influenced by the onset of action of other more direct local eliciting factors.     

Chronic gastritis in children

BACKGROUND: Active gastritis, atrophic gastritis (AG) and intestinal metaplasia are lesions associated with Helicobacter pylori (H. pylori) infection in adults. AIM: To assess the prevalence of chronic gastritis, its histological characteristics and clinical features in children. METHODS: 345 children (M/F: 151/194, mean age: 8.6 +/- 3.7 years; range: 1-18 years) were enrolled, referred for upper gastrointestinal endoscopy (UGI endo) with clinical manifestations of gastritis, i.e., recurrent abdominal pain (n = 232, 67.2%), upper gastrointestinal bleeding (n = 59, 17.1%) and miscellaneous (n = 53, 15.3%). Four perendoscopic gastric biopsy specimens (antrum: 2, fundus: 2) were taken. Biopsies were assessed and graded according to the updated Sydney system. H. pylori infection was considered if 2 out 3 tests were positive (culture, histology and rapid urease test), whereas 3 concordant negative results identified H. pylori negative children. RESULTS: H. pylori infection and chronic gastritis were detected in 215/345 (62.3%) (M/F: 104/117, sex ratio M/F = 0.89) and 221/345 (64.05%) children, respectively. Recurrent abdominal pain (n = 149, 67.4%) was the main clinical features of chronic gastritis followed by vomiting (n = 43, 19.5%) and upper gastrointestinal bleeding (n = 41, 18.6%). Any clinical features were however found to be specific. UGI endo showed; nodular gastritis (n = 90, 40.72%), congestive gastritis (n = 84, 38%), gastric ulcer (n = 9), bulbar ulcer (n = 5) and normal (n = 47, 21.2%). Chronic gastritis was active in 115 cases (52%) and was significantly associated with nodular gastritis (p < 0.05). Thirty two chronic gastritis (14.4%) exhibited AG (M/F: 16/16, mean age: 9.4 +/- 3.4 years) and 30/32 (93.7%) were H. pylori positive. AG was significantly associated with H. pylori infection (p < 0.0001) and nodular gastritis (p < 0.005). Active, follicular and AG were significantly associated with H. pylori infection (p < 0.00001). Three patients exhibited intestinal metaplasia. CONCLUSION: Chronic gastritis is frequent in children. Any clinical features were found to be specific. It significantly associated H. pylori infection and nodular gastritis. Atrophic gastritis was found in 14.5% of children.     

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.     

慢性萎缩性胃炎的胃黏膜保护机制的研究进展

慢性萎缩性胃炎是慢性胃炎的一种类型,其胃黏膜组织学病理表现为黏膜炎症、腺体萎缩、肠上皮化生和异型增生,而肠上皮化生被认为是萎缩的典型标志以及胃癌的前兆。胃黏膜保护机制可能与抑制胃酸分泌、抵抗H.pylori感染及热休克蛋白的启动等胃黏膜保护因子有关,热休克蛋白在抵御黏膜损害中起重要作用。     

PCR assay targeting virulence genes of Helicobacter pylori isolated from drinking water and clinical samples in Lahore metropolitan, Pakistan

Helicobacter pylorus is considered for chronic gastritis, gastric ulcers and adenocarcinoma and its high infection rate is observed in overcrowded and lower socioeconomic groups in developing countries. This study was designed to identify the role of drinking water in the transmission and prevalence of H. pylori (HP). Selective HP medium was developed for enrichment and presumptive identification of H. pylori by urease, catalase and species specific 16S rRNA tests. The virulence genes (vacA ‘s’ and ‘m’ regions and cagA) of H. pylori in 90 out of 225 H. pylori positive drinking water samples were present (40%). Ten out of 18 biopsies (55.55%) and 15 out of 50 vomiting fluids of gastric disease patients (30%) were also positive for virulence genes. Anti-H. pylori antibodies were also detected in 31 out of 50 patients’ sera. The presence of virulence genes was also directly confirmed by hybridization studies using non-radioactive DNA probes of 16S rRNA, vacA and cagA genes. The presence of H. pylori in water is due to poor sanitary conditions, improper waste disposal and lack of public health education. PCR-based analysis and colony hybridization can be used for detection of H. pylori in clinical and environmental samples.     

根除幽门螺杆菌对胃窦部黏膜萎缩和肠上皮化生的影响

目的比较幽门螺杆菌（Hp）根除前后胃窦部黏膜的病理变化,探讨根除Hp是否可以减少黏膜萎缩和肠上皮化生程度。方法将因上腹痛进行胃镜检查的病人180例随机分为Hp根除组98例和对照组82例,对Hp根除组给予抗Hp治疗,对照组仅给予对症治疗。再次进行胃镜检查,观察两组患者胃窦部病理变化。Hp检测采用Giemsa染色法和快速尿素酶试验,萎缩和肠上皮化生诊断采用HE染色。结果对病人两次胃镜检查的胃黏膜萎缩和肠上皮化生程度进行比较,Hp根除组黏膜萎缩程度减轻（P〈0.05）,对照组无变化（P〉0.05）;Hp根除组肠上皮化生程度减轻（P〈0.05）,对照组加重（P〈0.05）。结论根除Hp能够使胃窦黏膜萎缩程度和肠上皮化生程度减轻。     

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.     

Salt intake and type of intestinal metaplasia in Helicobacter pylori-infected Portuguese men

The relation between salt intake and intestinal metaplasia (IM) types and the potential interaction with H. pylori virulence are poorly understood and may contribute to further understand gastric carcinogenesis. We quantified the association between dietary salt exposure and complete, incomplete, and mixed IM, taking into account the potential effect modification according to the virulence of H. pylori infecting strains. H. pylori-infected male volunteers (n = 233) underwent an upper digestive endoscopy and completed questionnaires comprising different measures of salt exposure (main food items/groups contributing to dietary salt intake, estimated dietary sodium intake, visual analogical scale for salt intake, preference for salty/salted foods). A histological diagnosis was assigned based on the most severe lesion observed. H. pylori virulence was assessed by characterizing vacA and cagA genes. Odds ratios were estimated through age- and education-adjusted logistic regression models. The risk of IM was not significantly increased in H. pylori infected subjects with higher levels of salt consumption. The lack of association was consistent across measures of salt exposure, categories of H. pylori virulence, and types of IM. In conclusion, in this H. pylori positive population, salt intake did not increase the risk of any IM type, regardless of the virulence of the infecting strains.     

PTEN基因在胃癌组织中的表达及临床意义

目的研究正常胃粘膜、慢性萎缩性胃炎（伴肠化）、胃癌组织中抑癌基因PTEN的ⅢRNA和蛋白的表达情况,探讨其在在胃癌发生、发展中的作用及临床意义。方法（1）收集2011年11月--2012年11月期间内蒙古医学院第三附属医院病理和内窥镜结合确诊的正常胃组织30例、慢性萎缩性胃炎（伴肠化）30例．手术切除的45例胃癌标本并经病理确诊。（2）所有患者术前均未接受放、化疗和其他针对性抗肿瘤治疗,无其它肿瘤病史。（3）通过实时荧光定量PCR及Western印迹技术检测PTENmRNA及其蛋白在胃粘膜不同组织中的相对表达,所有数据采用SPSSl3．0统计软件包进行处理,统计学方法采用单因素方差分析及t检验,以P〈O．05为差异有统计学意义。结果（1）PTENmRNA在正常胃粘膜、慢性萎缩性胃炎（伴肠化）、胃癌中表达量分别为（1．902±0．981、1．158±0．241、0．740±0．221）,三组相比差异有统计学意义（F=3．292,P=O．041）。胃癌组织中PTENmRNA表达量分别与正常胃粘膜组织、慢性萎缩性胃炎（伴肠化）组相比,差别均有统计学意义（t=4．451,P=O．001;t=3．007,P=O．041）;（2）PTEN蛋白在正常胃粘膜、慢性萎缩性胃炎（伴肠化）、胃癌中表达量分别为（2．001i0．67I、1．141±0．326、0．599±0．220）,三组相比差异有统计学意义（F=4．122,P=O．030）。胃癌组织中PTEN蛋白的表达量与正常胃粘膜、慢性萎缩性胃炎（伴肠化）组相比,差别均有统计学意义（t=4．301,P=O．001;t=3．123,p-0．040）。结论PTEN基因在胃癌组织中表达降低和缺失与胃癌的发生密切相关,提示PTEN基因的表达可能为临床早期诊断胃癌提供新的指标。     

幽门螺杆菌密度和细胞毒素相关基因A在胃部疾病中的检测

目的探讨H.pylori的定植密度及cagA分布与慢性胃疾病病理类型的相互关系。方法胃镜直视下,取胃黏膜组织,经分离培养、快速尿素酶试验和W-S银染对H.pylori感染进行定性、定量诊断,用PCR检测H.pylori的cagA基因,以SPSS软件分析数据。结果①H.pylori在慢性胃部疾病的阳性率为84.6%。cagA阳性率为62.5%,在慢性胃炎,不典型增生,胃癌中的分布分别为:58.0%,70.6%,72.2%,3组间差异无统计学意义(χ2(2,104)=1.804,P=0.406);②H.pylori定植密度在胃黏膜中的分布分别为:1级16(13.0%),2级44(35.8%),3级44(35.8%)。其中慢性胃炎组的分布分别为:1级13(15.9%),2级24(29.3%),3级32(39.0%);不典型增生组的分布分别为:1级1(5.0%),2级8(40.0%),3级8(40.0%);胃癌组中的分布分别为:1级2(9.5%),2级12(57.1%),3级4(19.0%)。密度级别在慢性胃炎、不典型增生、胃癌组的分布差异无统计学意义(χ2(2,123)=7.724,P=0.259)。结论①太原地区慢性胃部疾病患者中H.pylori呈高感染率,且cagA阳性率较高,后者随着疾病的严重程度有增高趋势,但差异无统计学意义,提示ca-gA可能不是影响胃部疾病病理类型的独立因素;②胃部疾病患者中,H.pylori定植密度级别与胃部疾病病理类型无一定的规律。     

中国香港地区幽门螺杆菌毒力基因型与十二指肠溃疡关系的研究

目的：研究幽门螺杆菌（Hp）的重要毒力因子vacA，cagA，iceA及插入序列IS在中国香港地区分离菌株中的分布特征及其与十二指肠溃疡的关系。方法：采用聚合酶链反应（PCR）和Southern blot方法，对72例证实为Hp感染的胃十二指肠疾病患者的胃黏膜标本直接进行检测。结果：72例患者中，69例（95.8％）感染的Hp菌株为vacA sIc型，3例（4.2％）为sIa型；23例（31.9％）为vacAm1b型，46例（63.9％）为vacAm2型；6例（8.3％）为混合型。63.9％（46/72）的患者感染菌株为iceA1型，29.2％（21/72）为iceA2型。CagA的阳性率为88.9％（64/72）。结论：Hp毒力因子vacA，cagA和iceA在香港菌株中的分布有自己的特点；未发现特定cagA，vacA和iceA基因型别与DU相关。     

Helicobacter pylori infection, garlic intake and precancerous lesions in a Chinese population at low risk of gastric cancer

BACKGROUND: Cangshan County of Shandong Province has one of the lowest rates of gastric cancer (GC) in China. While intestinal metaplasia (IM) and dysplasia (DYS) are less common in Cangshan than in areas of Shandong at high risk of GC, these precursor lesions nevertheless affect about 20% of adults age > or = 55. SUBJECTS AND SETTING: In order to evaluate determinants of IM and DYS in Cangshan County, a low risk area of GC a survey was conducted among 214 adults who participated in a gastroscopic screening survey in Cangshan County in 1994. METHOD: A dietary interview and measurement of serum Helicobacter pylori antibodies were performed. RESULTS: The prevalence of H. pylori was lowest (19%) among those with normal gastric mucosa, rising steadily to 35% for superficial gastritis (SG), 56% for chronic atrophic gastritis (CAG), 80% for IM, and 100% for DYS. The prevalence odds of precancerous lesions were compared with the odds of normal histology or SG. The odds ratio (OR) or CAG associated with H. pylori positivity was 4.2 (95% confidence interval [CI] : 1.7-10.0), while the OR of IM/DYS associated with H. pylori positivity was 31.5 (95% CI: 5.2-187). After adjusting for H. pylori infection, drinking alcohol was a risk factor for CAG (OR = 3.2, 95% CI: 1.1-9.2) and IM/DYS (OR = 7.8, 95% CI: 1.3-47.7). On the other hand, consumption of garlic showed non-significant protective effects and an inverse association with H. pylori infection. CONCLUSIONS: The findings of this study suggest that infection with H. pylori is a risk factor and garlic may be protective, in the development and progression of advanced precancerous gastric lesions in an area of China at relatively low risk of GC.