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21.
Gastric MALT lymphoma usually develops from chronic gastritis, the vast majority of which (>90%) is associated with Helicobacter pylori infection. We sequenced the third complementarity determining region (CDR3) of immunoglobulin heavy chain genes in 19 gastric MALT lymphoma clones to determine the pattern of variable (V), diversity (D) and joining (J) gene utilization during immunoglobulin gene rearrangement.
DNA was extracted from paraffin-embedded sections and the rearranged CDR3 regions were amplified using a semi-nested polymerase chain reaction (with primers complementary to the conserved framework-three segment of the variable region [FR3A] and J regions). The DNA used for cloning and sequencing was obtained after purification of monoclonal bands excised from polyacrylamide gels. The N-D-N region specific to each clone was compared with known germline D sequences.
Similarly to that observed in normal and leukaemic B cells, our series of gastric MALT lymphomas showed apparent preferential utilization of genes from the DXP family. In two cases no similarity between the CDR3 nucleotide sequences of the neoplastic clones and the known germline D sequences could be found. In 10/19 analysed alleles the lymphoma B-cell clones appeared to contain two D gene segments (D-D recombination), a rare occurrence in normal individuals but one which has been described as a significant event in the determination of idiotype expression and antigen-binding affinity. Remarkably, despite the use of different D and J segments, the resultant amino acid sequences matched in two patients, suggesting the presence of a common selecting antigen.
The observed pattern of D gene rearrangement suggests that MALT lymphoma B-cell clones have undergone antigen selection, which seems to indicate that the antigen stimulation plays a pivotal role in the development of the lymphoma.  相似文献   
22.
目的:通过几种不同的检查方法调查人胃螺杆菌在人群中的感染情况及在慢性胃炎中的致病作用。方法:380例行消化道症状的就诊患者和432名健康体检者的胃粘膜活检标本分别行涂片、尿素酶试验、14C-尿素呼吸试验和组织学检查。结果:人胃螺杆菌在上述两类人群中的感染率分别为2.11%和1.16%。涂片Gram染色和切片WS银染是目前诊断该菌感染较理想的手段,不论有无症状,患者在组织学上均伴有慢性炎症改变,根据形态学特点该菌可大致分为两型,分别与某些动物胃内的螺旋菌相似。结论:人胃螺杆菌在人群中感染率较低,可能是一种源自动物的慢性胃炎相关性病原菌。  相似文献   
23.
置幽门螺杆菌(HP)悬液于含人喉癌上皮细胞(Hep-2)或人胃癌上皮细胞(MKN-28)的培养瓶内,经2h或3.5h培养后观察HP对细胞的粘附情况。结果发现HP能成丛地粘附在上皮细胞表面,少数侵入胞浆内。HP对MKN-28粘附率明显高于对Hep-2细胞者。随菌龄的延长或菌株的变异,HP的粘附作用明显减弱。1%D-甘露糖对HP的粘附性有部分阻抑作用。  相似文献   
24.
目的 比较雷贝拉唑与奥美拉唑三联疗法根除幽门螺杆菌(Hp)的疗效与细胞色素氧化酶P4502 C19(CYP 2C19)基因多态性的关系。方法 采用随机、对照研究方法,将169例因消化不良症状接受常规胃镜检查确诊为慢性胃炎且Hp阳性的连续患者分人两组:雷贝拉唑三联疗法组(RAC组85例)和奥美拉唑三联疗法组(OAC组84例)。Hp诊断依靠组织病理学检查并参考快速尿素酶试验、血清Hp抗体检测结果。RAC组、OAC组均给予三联治疗:RAC组:雷贝拉唑10mg,OAC组:奥美拉唑20mg,两组均联用羟氨苄青霉素1000mg和克拉霉素500mg,全部药物每日2次,疗程7d。采用聚合酶链式反应结合限制性内切酶技术(PCR-RFLP),进行CYP 2C19基因型分析,治疗结束后第28天用^14C尿素呼气实验检测Hp根除疗效。结果 160例完成治疗方案,RAC组及OAC组的Hp根除率按PP分析及ITT分析均无统计学差异(P〉0.05)。根据CYP 2C19基因型分析,160例中,弱代谢型(PM)、中间代谢型(IM)及强代谢型(EM)的Hp根除率分别为95.5%(21/22)、85.9%(73/85)和67.9%(36/53)。PM型及IM型的Hp根除率均显著高于EM型(P〈0.05),而PM型与IM型间差异无统计学意义(P〉0.05)。RAC组中,各基因型的Hp根除率差异无统计学意义(P〉0.05)。OAC组中。IM型与EM型间(P〈0.01)及EM型与PM型间(P〈0.05)差异均有统计学意义。结论 雷贝拉唑与奥美拉唑两种三联疗法均能有效根除Hp。总疗效差异无统计学意义。雷贝拉唑三联疗法疗效较稳定,个体间差异小。PM型及IM型的Hp根除率均较EM型为高。  相似文献   
25.
目的研究新疆维吾尔族慢性胃炎患者HLA-DRB1等位基因与幽门螺杆菌(Hp)感染的关系。方法采用幽门螺杆菌分离培养技术检测33例维吾尔族慢性胃炎患者幽门螺杆菌感染情况,采用PCR-SSP检测HLA-DRB1*0405、HLA-DRB1*08、HLA-DRB1*12等位基因,并与36例汉族慢性胃炎患者进行比较。结果1)新疆维吾尔族慢性胃炎患者Hp阳性率(78.8%)显著高于汉族慢性胃炎患者(58.3%)(P〈0.05);2)维吾尔族、汉族慢性胃炎患者Hp感染与HLA-DRB1*0405、HLA-DRB1*08、HLA-DRB1*12等位基因无相关性(P〉0.05)。结论1)维吾尔族慢性胃炎患者Hp感染率高于汉族慢性胃炎患者;2)维吾尔族、汉族慢性胃炎患者Hp感染与HLA-DRB1*0405、HLA-DRB1*08、HLA-DRB1*12等位基因无关。  相似文献   
26.
BACKGROUND: The purpose of this study was to analyze the frequency and results of preoperative biliary and gastrointestinal (GI) evaluation of patients undergoing Roux-en-Y gastric bypass (RYGB). METHODS: Retrospective review of the preoperative evaluation of 144 consecutive RYGB patients. RESULTS: Cholecystectomy had already been performed in 43 (30%) patients; 22% of those patients with an intact gallbladder had cholelithiasis. Ten patients (7%) had an upper GI x-ray (UGI), and 94 patients (65%) had an esophagogastroduodenoscopy (EGD). Abnormalities were found in 40% of the UGIs and 84% of the EGDs. A total of 96 patients (67%) were tested for Helicobacter pylori; 11% were positive. Twenty-one patients (15%) underwent preoperative colonoscopy; 48% were abnormal, but most of the abnormalities were not clinically significant. Three patients had barium enema x-ray, which was normal in all cases. CONCLUSIONS: The preoperative biliary and GI evaluation of bariatric surgery patients should include a routine ultrasound of the gallbladder. Routine preoperative EGD will detect a significant number of abnormalities that should be treated, but should rarely alter the bariatric surgical procedure or result in denial of bariatric surgery. Many abnormalities will be asymptomatic. Patients should be routinely screened for H. pylori and, if positive, treated before bariatric surgery. Lower GI evaluation should be performed selectively based on the patient's symptoms, physical findings, and guidelines for colorectal cancer and polyp screening.  相似文献   
27.
目的 探讨幽门螺杆菌(Hp)感染病人中Hp细胞毒相关蛋白(CagA)、细胞空泡毒素(VacA)抗体在胃十二指肠疾病的比例,并评估不同类型幽门螺杆菌感染对胃窦粘膜炎症程度的影响。方法 应用免疫印迹法测定Hp感染者病人体内的CagA、VacA抗体。结果 73%的Hp感染者病人中出现CagA抗体,61%Hp感染者病人中出现VacA抗体。CagA抗体和VacA抗体在各疾病之间差异无显著性(P>0.05)。在胃溃疡、十二指肠溃疡和复合性溃疡三类病人中,具CagA和VacA双阳性的比例较CagA和VacA双阴性的比例差异有显著性(P<0.05)。胃窦萎缩病变在CagA和VacA双阳性的病人中比CagA和VacA双阴性的病人严重(P<0.05)。结论 具有高毒力因子(CagA和VacA)的Hp是胃肠疾病病人感染的常见菌株,具有CagA和VacA的Hp可能在诱导胃粘膜发展到萎缩病变过程中起重要作用。但不能作为特异性指标来判断胃十二指肠疾病。  相似文献   
28.
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  相似文献   
29.
陈浩  郑君杰 《广西医学》2003,25(6):912-914
目的:研究短程三联治疗幽门螺杆菌相关性十二指肠溃疡的疗效。方法:胃镜病理检查证实十二指肠单发溃疡活动期(A期)伴Hp感染的患分为一周组及维持组,均予三联抗幽门螺杆菌治疗。一周组治疗一周后即停止一切药物治疗,维持组则继续抗酸治疗四周,之后停药。两组均于治疗结束后四周及一年后复查胃镜及病理检查,了解所有患溃疡的愈合及幽门螺杆菌根除情况。结果:经三联抗幽门螺杆菌治疗结束后一年复查胃镜及病理检查,一周组溃疡愈合率83%,幽门螺杆菌根除率75%;维持组溃疡愈合率94%,幽门螺杆菌根除率80%。两组愈合率及幽门螺杆菌根除率相比较,差异无显性。经三联抗幽门螺杆菌治疗结束后一年,Hp根除组溃疡愈合率96%,Hp未根除组溃疡愈合率64%,差异有显性。结论:治疗十二指肠溃疡及预防复发,关健是根除Hp而不是长期抗酸治疗。  相似文献   
30.
BACKGROUND: Change in apoptosis in gastric glands after eradication of Helicobacter pylori has never been reported. AIMS: The purpose of this paper is to investigate the change in apoptosis in gastric glands after eradication of Heliobacter pylori. PATIENTS AND METHODS: We studied 23 Heliobacter pylori-positive patients with duodenal and gastric ulcers, who were monitored for 6-12 months after eradication, and eight controls. Biopsies were taken from the antrum and body. Apoptosis was evaluated immunohistochemically using anti-single stranded DNA antibody. Apoptotic index was calculated by counting immunostained cells in surface epithelial and glandular cells. RESULTS: In the surface epithelium, Apoptotic indexes were significantly higher in patients than in controls. In the upper portion of fundic glands, apoptotic indexes were significantly higher in patients with gastric ulcers (14.2% (9.3, 17.8)) (median (1st quartile, 3rd quartile)) than in controls (8.0% (2.0, 9.0), p < 0.01) and decreased significantly after eradication (3.4% (2.0, 5.3)), p < 0.01). In pyloric glands, apoptotic indexes were no different between patients and controls. In the lower portion of fundic glands, apoptotic indexes were very low, both in patients and in controls. CONCLUSIONS: Our results showed that apoptosis, not only of surface epithelial cells but also of glandular cells in the upper portion of fundic glands, increased in Heliobacter pylori-positive patients with gastric ulcers and decreased to normal levels after eradication of Heliobacter pylori.  相似文献   
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