Neural network application in the discrimination of benign from malignant gastric cells

OBJECTIVE: To investigate the potential value of morphometry and neural networks for the discrimination of benign from malignant gastric lesions. STUDY DESIGN: One thousand cells from 19 cases of cancer, 19 cases of gastritis and 56 cases of ulcer were selected as a training set, and an additional 4,000 cells from the same cases of cancer, gastritis and ulcer were used as a test set. Images of routinely processed gastric smears stained by the Papanicolaou technique were analyzed by a custom-made image analysis system. RESULTS: Application of the neural network gave correct classification in 96% of benign cells and 89% of malignant cells. CONCLUSION: The results indicate that the use of neural networks and image morphometry may offer useful information concerning the potential of malignancy in gastric cells.     

Application of discriminant analysis and quantitative cytologic examination to gastric lesions

OBJECTIVE: To investigate of the potential value of morphometry and discriminant analysis for the classification of benign and malignant gastric cells and lesions. STUDY DESIGN: The data set consisted of 13,300 cells from 120 cases composed of 30 cases of cancer, 26 cases of gastritis and 64 cases of ulcer according to the final histologic diagnosis. The cytologic diagnosis was divided into 5 categories (gastritis, ulcer, inflammatory dysplasia, cancer and true dysplasia). Classification was attempted at 2 levels: the cell level to classify individual cells and the case level to classify individual cases. For the cellular classification the measured cells from 50% of available cases were selected as a training set to construct a model. The cells from the remaining cases were used as a test set to validate the model. Similarly for case classification, the same 50% of cases that were used for cell classification were used as a training set and the remaining cases as a test set. Images of routinely processed gastric smears stained by the Papanicolaou technique were analyzed by a customized image analysis system. RESULTS: Application of discriminant analysis on the test set gave correct classification of 98.4% of benign cells and 67.1% of malignant cells. On case classification, 100% accuracy was achieved for benign and malignant cases, both for the training and test sets. CONCLUSION: The application of discriminant analysis described in this paper could produce significant classification results at the cellular and individual case level.     

慢性胃病患者胃蛋白酶原I、II水平与幽门螺旋杆菌感染的关系研究

目的:探讨慢性胃病患者胃蛋白酶原(PG)Ⅰ、PG Ⅱ水平与幽门螺旋杆菌(HP)感染的关系。方法:选取2012年12月-2016年12月期间我院收治的慢性胃病患者64例作为研究对象,根据疾病类型分为慢性胃炎组23例、胃溃疡组22例以及胃癌组19例。另取同期于我院接受体检的健康志愿者30例作为对照组,应用免疫比浊法测定各组血清PG Ⅰ与PG Ⅱ水平,采用快速尿激酶法测定各组HP感染情况,分别对比各组研究对象HP感染发生情况,血清PG Ⅰ、PG Ⅱ、PG Ⅰ/PG Ⅱ水平,HP感染情况与血清PG Ⅰ、PG Ⅱ、PG Ⅰ/PG Ⅱ水平关系。结果:慢性胃炎组、胃溃疡组以及胃癌组患者HP阳性率分别为60.87%、63.64%、78.95%,均明显高于对照组的13.33%(P0.05)。慢性胃炎组、胃溃疡组以及胃癌组患者血清PG Ⅰ、PG Ⅰ/PG Ⅱ水平均低于对照组,且胃癌组低于慢性胃炎组与胃溃疡组(P0.05),慢性胃炎组和胃溃疡组血清PG Ⅰ、PG Ⅰ/PG Ⅱ水平比较差异无统计学意义(P0.05),各组血清PG Ⅱ比较无统计学差异(P0.05)。各组研究对象HP阳性血清PG Ⅰ、PG Ⅰ/PG Ⅱ水平均低于HP阴性(P0.05),而PG Ⅱ水平比较无统计学差异(P0.05),慢性胃炎组、胃溃疡组、胃癌组HP阳性血清PG Ⅰ水平低于对照组,且胃癌组低于慢性胃炎组、胃溃疡组(P0.05),胃溃疡组、胃癌组HP阳性血清PG Ⅰ/PG Ⅱ水平低于对照组,且胃癌组低于慢性胃炎组(P0.05)。结论:慢性胃病患者PG Ⅰ、PG Ⅱ水平异常降低,HP阳性患者PG Ⅰ、PG Ⅱ水平降低更为明显,随病变的程度增加,血清PG Ⅰ、PG Ⅰ/PG Ⅱ水平也呈现出下降的趋势。     

Survivin与VEGF在良、恶性胃溃疡组织中的表达及研究

目的:研究凋亡基因生存素(Survivin)及血管内皮生长因子(VEGF)在良、恶性胃溃疡中的表达及二者在溃疡型胃癌中的表达与临床病理特征之间的关系,分析二者在胃癌发生发展中的作用和在胃癌中表达的相关性。方法:应用免疫组化S-P染色检测Survivin及VEGF在良性胃溃疡,胃溃疡伴中-重度不典型增生和溃疡性胃癌中的表达,结合临床病理特征进行相关分析。结果:Survivin及VEGF在良性胃溃疡中的表达率分别为16.2%、24.3%,在胃溃疡伴中-重度不典型中的表达率分别为52.3%、45.5%,在溃疡型胃癌中的表达率分别为71.4%、55.4%,差异具有显著性(P0.01);Survivin和VEGF的表达与溃疡型胃癌的浸润深度、淋巴结转移、TNM分期具有相关性。Survivin和VEGF的表达亦呈正相关。结论:Survivin基因在溃疡型胃癌组织中的表达显著增高,是胃癌演变进程中的重要步骤,过表达Survivin可能提示预后不良。Survivin对胃癌的诊断及预后有潜在的应用价值。Survivin和VEGF在溃疡型胃癌的发生发展中起协同作用,动态随访二者对胃溃疡的演变可能有一定的价值,可作为判断肿瘤进程和浸润转移的生物学指标。Survivin及VEGF的联合检测可能对胃癌的综合治疗提供理论依据,对其进行深入研究有望为胃癌的诊疗开辟新的天地。     

31例胃癌患者胃液SIgA及胃粘膜产亚硝酸真杆菌测定结果分析

探讨了胃癌病变局部免疫功能及胃粘膜细菌分布与发病机制的关系.采用放射免疫法对31例胃癌患者(实验组)与56例其它胃病患者(实验组)进行胃液SIgA含量的测定并对胃粘膜病变部位进行细菌分离培养、涂片染色镜检.结果显示,实验组较对照组胃液SIgA含量显著增多(p<0.05),胃粘膜产亚硝酸真杆菌阳性检出率亦明显升高(p<0.01).胃癌患者胃粘膜局部免疫功能失常,其发病可能与产亚硝酸真杆菌有关,胃液SIgA的测定对估价预后有一定意义.     

小儿消化性疾病的胃电图变化及与临床特点和胃镜特征的关联性

目的:分析小儿消化性疾病的胃电图变化及与临床病理特征和胃镜特征的关联性。方法:选取2018年1月至2019年5月我院儿科收治的经胃镜和病理学两种方式诊断为消化性疾病的患儿54例为观察组,另选取无胃肠道疾病的健康儿童40例为对照组。比较两组胃电图参数(频率均值和波幅均值),54例胃电图诊断后纤维胃镜检查结果,分析消化性疾病患儿HP感染与临床病理特征、溃疡面积的关系。结果:各组胃病患者胃电慢波频率均值各不相同(P0.05),三组患者胃电慢波波幅均值相比差异具有统计学意义(P0.05);且浅表性胃炎组、胆汁反流性胃炎组患者胃电慢波频率均值、胃电慢波波幅均显著低于胃溃疡组(P0.05);浅表性胃炎组患者胃电慢波频率均值显著低于胆汁反流性胃炎组(P0.05)。胆汁反流性胃炎组患者胃电慢波波幅显著低于浅表性胃炎组(P0.05)。胃镜检查结果显示,其中浅表性胃炎的诊断符合率较高,达90.00%,胃溃疡符合率为60.71%,胆汁反流性胃炎符合率为83.33%。HP检测结果显示,HP阳性患儿占总例数的77.78%(42/54),HP阴性患儿占总例数的22.22%(12/54);HP阳性组患儿淋巴滤泡形成、胃黏膜萎缩、胃黏膜炎性活动的发生率明显高于HP阴性组,差异具有统计学意义(P0.01);HP阳性组溃疡范围2 cm的患儿比例明显高于HP阴性患儿,差异具有统计学意义(P0.01)。结论:小儿消化性疾病胃电图存在餐后NSWP的下降及节律过缓的上升,胃电图检查和胃镜检查在诊断上有较高的符合率,HP感染科引起胃黏膜组织学改变,可作为小儿消化性疾病的靶向治疗。     

Potential of radial basis function neural networks in discriminating benign from malignant lesions of the lower urinary tract

OBJECTIVE: To investigate the potential value of morphometry and neural network tools for discriminating benign from malignant nuclei and lesions of the lower urinary tract. STUDY DESIGN: The study group consisted of 33 cases of lithiasis, 41 cases of inflammation, 66 cases of benign hyperplasia of the prostate, 4 cases of carcinoma in situ, 48 cases of grade 1 transitional cell carcinoma of the bladder (TCCB) and 123 cases of grade 2 and 3 TCCB. Images of routinely processed voided urine smears stained by the Giemsa technique were analyzed by a custom image analysis system. Analysis of the images gave a data set of features from 31,158 nuclei. A radial basis function (RBF)-type neural network was employed to discriminate benign from malignant nuclei, based on the extracted morphometric and textural features. Subsequently a second RBF classifier was employed to discriminate benign from malignant cases. The nuclei from 156 randomly selected cases (50% of total cases) was used as a training set, and the nuclei from the remaining 159 cases made up the test set. Similarly, in an attempt to discriminate at the patient level, the same 156 cases were used to train an RBF classifier; the remaining 159 cases were used for the test set. The cases used for training and testing the 2 classifiers (nuclear and patient level) were the same for the 2 kinds of classifiers. RESULTS: Application of the RBF classifier permitted the correct classification of 93.64% of benign nuclei and 85.61% of malignant, giving an overall accuracy of 84.45%. At the patient level the RBF classifier permitted an overall accuracy of 94.97%. These results were on the test sets. CONCLUSION: The role of nuclear morphologic features in the cytologic diagnosis of lower urinary tract alterations was confirmed by the results of this study. The observed overlap in feature space indicates that the nuclear characteristics do not form strictly separate clusters; that fact explains the difficulty morphologists have with reproducible identification of nuclei from the lower urinary tract. Application of RBF offers good classification at the nuclear and patient level and promises to become a powerful tool for everyday practice in the cytologic laboratory.     

Helicobacter pylori strain and the pattern of gastritis among first-degree relatives of patients with gastric carcinoma

Background. Relatives of gastric cancer patients have an increased risk of gastric cancer, possibly related to genetically‐related strains of Helicobacter pylori or a common environment. Methods. The pattern of gastritis and H. pylori from gastric cancer patients and their first‐degree relatives were compared using detailed DNA fingerprints and vacA, cagA, and iceA genotyping. Results. Sixteen index cases from Korea, the US, or Colombia and their 38 first‐degree relatives (brothers, sisters, sons and daughters) were studied. No definite, or consistent, relationship between the pattern of gastritis and the relatedness of the H. pylori strain was observed (i.e. relatives could have an identical or a totally different pattern of gastritis regardless if they were infected with identical or highly similar organisms). For example, three elderly siblings of an index case with atrophic pangastritis had identical H. pylori isolates and environments in childhood and yet two had antral predominant nonatrophic gastritis, which is typically associated with duodenal ulcer instead of gastric cancer. Conclusions. The results of this study are not consistent with the hypothesis that specific virulence factors or similar H. pylori strains correlate with a specific histologic pattern or outcome even among those sharing the same environment in childhood.     

Diagnosis of Helicobacter pylori in gastric brush and biopsy specimens stained by Rowmanowsky and immunocytochemical methods: comparison with the CLOtest

Helicobacter pylori has been implicated in the pathogenesis of chronic gastritis, gastric and duodenal ulcer, and possibly gastric carcinoma. The organism may be detected by invasive or non‐invasive methods with variable sensitivity. Paired gastric biopsy and gastric brush specimens were collected from 83 patients presenting with non‐ulcer dyspepsia. One biopsy was tested for urease using the CLOtest, the other was processed to paraffin and consecutive sections were stained with haematoxylin and eosin, modified Giemsa and anti‐ H. pylori antisera. The brush specimens were stained with a rapid Romanowsky stain (Hema‐Gurr) and anti‐ H. pylori . The CLOtest was positive in 31 cases, the Giemsa biopsy in 25, the anti‐ H. pylori biopsy in 27, the Hema‐Gurr smear in 27 and the anti‐ H. pylori smear in 19. The sensitivities of the methods after omitting one inadequate biopsy were 96%, 93%, 100%, 96% and 78%, respectively. The specificities were 93% for the CLOtest and 100% for the other methods. While immunocytochemical staining of gastric biopsies may be the most sensitive method for H. pylori identification, the cost and turn around time of the technique may preclude its routine use. Gastric brush cytology is a highly sensitive and specific method for H. pylori detection that is quick and simple to perform. Its application is recommended for the routine diagnosis of H. pylori infection.     

Fine needle aspiration biopsy of the breast. Value of nuclear morphometry after different sampling methods

OBJECTIVE: To study the potential of nuclear morphometry in supporting the interpretation of fine needle aspiration biopsy (FNAB) samples of the breast fixed in 50% ethanol and centrifuged on slides. STUDY DESIGN: Computerized morphometry was used to outline the nuclei of breast epithelial cells in breast cancer, fibroadenoma and fibrocystic disease. The diagnoses were histologically confirmed. We applied 2 different sampling methods (measurements done on cell groups and on free cells). RESULTS: The mean nuclear area of cell groups of malignant samples (23) varied from 42 to 125 microns 2, in fibroadenomas from 30 to 50 microns 2 and in fibrocystic disease from 26 to 57 microns 2. The mean nuclear area of free cells varied as follows: cancer, 66-181 microns 2; fibroadenoma, 33-70 microns 2; fibrocystic disease, 35-60 microns 2. Apocrine metaplasia was excluded from comparison on a morphologic basis. CONCLUSION: The study suggests that if the mean nuclear area of cell groups is < 42 microns 2, the lesion is probably benign; if > 57 microns 2, and apocrine metaplasia is excluded, malignancy should be considered. The differential diagnosis between carcinoma and fibroadenoma could be based on free cells: mean area of free cell nuclei < or = 65 microns 2 suggested a benign lesion, and of > or = 71 microns 2 suggested a malignant lesion. Morphometric nuclear size features (exemplified by nuclear area) appeared efficient in distinguishing between malignant and benign lesions when measured from free cells and cell groups.     

PGI、PGⅡ在胃癌组织中的表达及意义

目的：研究胃蛋白酶原I(PGI)、胃蛋白酶原Ⅱ(PGⅡ)在胃癌组织中的表达及意义。方法：将我院2011 年5 月至2013年10月 收治的上消化道疾病患者243 例纳入研究,根据胃镜及病理组织学结果,按照胃癌、慢性萎缩性胃炎、慢性非萎缩性胃炎、不典型 增生以及胃溃疡分为5 组,对照组为57 名来我院检查的健康的人群。应用酶联免疫法测定各组血清PGI、PGⅡ的含量并计算胃 蛋白酶原比值(PGR),比较胃癌患者手术前后血清PGI、PGⅡ的含量以及PGR,并通过ROC曲线下面积评价血清PGI、PGⅡ以及 PGR 诊断胃癌的效能。结果：与对照组比较,胃溃疡组PG I、PG II均明显升高,PGR 降低(P<0.05),慢性萎缩性胃炎组、不典型增生 组及胃癌组PGI、PGR均明显降低(P<0.05);与慢性萎缩性胃炎组比较,不典型增生组和胃癌组PGR 显著降低(P<0.05)。手术治疗 后,胃癌患者血清PGⅠ、PGⅡ含量较手术前明显下降(P＜0.05)。血清PGⅠ、PGⅡ以及PGR含量诊断胃癌的ROC 曲线下面积依 次为0.779、0.920 以及0.991。结论：胃癌患者血清PGI、PGR均明显降低,二者可用于初步筛查胃癌。     

Diagnosis of early gastric cancer based on fluorescence hyperspectral imaging technology combined with partial‐least‐square discriminant analysis and support vector machine

This study investigated the feasibility of using fluorescence hyperspectral imaging technology to diagnose of early‐stage gastric cancer. Fluorescence spectral images of 76 patients who were pathologically diagnosed as non‐atrophic gastritis, premalignant lesions and gastric cancer were collected. Fluorescence spectra at 100‐pixel points were randomly extracted after binarization. Diagnostic models of non‐atrophic gastritis, premalignant lesions and gastric cancer were constructed through partial‐least‐square discriminant analysis (PLS‐DA) and support vector machine (SVM) algorithms. The prediction effects of PLS‐DA and SVM models were compared. Results showed that the average spectra of normal, precancerous and gastric cancer tissues significantly differed at 496, 546, 640 and 670 nm, and regular changes in fluorescence intensity at 546 nm were in the following order: normal > precancerous lesions > gastric cancer. Additionally, the effect of the diagnostic model established by SVM is significantly better than PLS‐DA which accuracy, specificity and sensitivity are above 94%. Experimental results revealed that the fast diagnostic model of early gastric cancer by combining fluorescence hyperspectral imaging technology and improved SVM was effective and feasible, thereby providing an accurate and rapid method for diagnosing early‐stage gastric cancer.      

Higher number of <Emphasis Type="Italic">Helicobacter pylori</Emphasis> CagA EPIYA C phosphorylation sites increases the risk of gastric cancer,but not duodenal ulcer

Background  

Helicobacter pylori infection is one of the most common infections worldwide and is associated with gastric cancer and peptic ulcer. Bacterial virulence factors such as CagA have been shown to increase the risk of both diseases. Studies have suggested a causal role for CagA EPIYA polymorphisms in gastric carcinogenesis, and it has been shown to be geographically diverse. We studied associations between H. pylori CagA EPIYA patterns and gastric cancer and duodenal ulcer, in an ethnically admixed Western population from Brazil. CagA EPIYA was determined by PCR and confirmed by sequencing. A total of 436 patients were included, being 188 with gastric cancer, 112 with duodenal ulcer and 136 with gastritis.     

树突状细胞对胃癌前病变的免疫保护分析

摘要 目的：探究树突状细胞(Dendritic cells,DC)对胃癌的免疫保护作用。方法：选择2016年1月至2018年1月于我院接受治疗的145例胃癌、39例慢性萎缩性胃炎、21例不典型增生、27例肠上皮化生以及20例正常对照组患者为研究对象,分别采集其胃粘膜标本进行染色,记录和比较其胃粘膜中S100⁺、CD4⁺和CD8⁺细胞的数量、平均面积以及平均吸光度,并将胃癌患者分为中分化腺癌(49例)、低分化腺癌(53例)和未分化癌(43例)进行对比。结果：(1)胃癌组、慢性萎缩性胃炎组、不典型增生、肠上皮化生组的胃粘膜S100⁺阳性细胞计数明显高于正常对照组（P<0.05）,胃癌组平均吸光度低于对照组,其他3组平均吸光度显著高于对照组,(P<0.05);胃癌组平均面积与正常对照组相比无差异(P>0.05),其他三组平均面积显著高于对照组（P<0.05）;(2)慢性萎缩性胃炎组、肠上皮化生组、不典型增生组患者CD4⁺细胞数均低于对照组(P<0.05);胃癌组、慢性萎缩性胃炎组、肠上皮化生组患者平均面积均低于对照组(P<0.05);胃癌组、慢性萎缩性胃炎组、不典型增生、肠上皮化生组平均吸光度均低于对照组(P<0.05);(3)慢性萎缩性胃炎组、肠上皮化生组、不典型增生组患者CD8⁺细胞数明显高于对照组(P<0.05),胃癌组稍低于对照组(P>0.05);胃癌组患者平均面积低于对照组(P<0.05);胃癌组患者平均吸光值低于对照组,慢性萎缩性胃炎组、肠上皮化生组患者高于对照组(P均<0.05);(4)随着胃癌分化程度的降低,胃癌患者DC细胞数有降低趋势。结论：胃癌前病变患者胃粘膜中DC数量会显著增多,免疫功能加强,DC细胞数量会随胃癌分化程度的降低而减少,分析其原因与DC细胞能够抑制癌前病变有关。     

胃病患者胃黏膜真菌感染的检测

通过检测胃炎和胃溃疡、胃癌患者胃黏膜寄居的真菌,了解胃黏膜真菌的菌种多样性及其与胃溃疡的关系。采集消化科就诊患者胃镜钳取的胃黏膜标本63例,采用念珠菌显色培养基(CHROMagar)进行真菌分离培养鉴定。用玉米吐温80培养基进行真菌孢子形态学检查,用ITS(internal transcribed spacer region)序列限制性片段长度多态性(Restriction fragment length polymorphism,RFLP)检测分析真菌菌种多样性。分离培养真菌32(32/63,50.8%)株,经ITS序列RFLP法鉴定为白假丝酵母菌31株,光滑假丝酵母菌1株。真菌阳性率与病理诊断成正相关(r=0.263,P=0.027),与性别、年龄、吸烟、饮酒、学历的相关性均无统计学意义(P0.05)。结果表明,胃黏膜寄居的真菌存在多样性,且真菌阳性率与病理损害程度存在相关性。     

Utilization of Proteinase K-Treated Cells as Lipopolysaccharide Antigens for the Serodiagnosis of Helicobacter pylori Infections

We have evaluated the use of proteinase K (PK)-treated cells isolated from Helicobacter pylori as lipopolysaccharide (LPS) antigens in an immunoblot assay and an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of H. pylori infection. The sera from patients with chronic gastritis, gastric ulcer, duodenal ulcer or gastric cancer, and from healthy adults with or without H. pylori infection were assayed with three commercial serodiagnostic kits (HM-CAP, Helico-G, and G.A.P. II) and novel methods relying on the use of PK-treated cells. The PK-treated cells used in these assays were selected on the basis of their possibility to possess a common epitope in the O-polysaccharides of H. pylori, which is known to be highly immunogenic in humans. Of the sera from these patients, 71-94% were positive with the commercial kits, 97% with immunoblot assay, and 90% with ELISA. On the other hand, of the healthy adults infected with H. pylori, 72-97% were positive with the commercial kits, 86% with immunoblot assay, and 72% with ELISA. PK-treated cells that did not contain the common epitope were unsuitable as an antigen for immunoblot assay or ELISA. Furthermore, the reactivity of these sera reacted specifically with H. pylori PK-treated cells but not with LPSs from other gram-negative bacteria, such as Campylobacter, Proteus, Bordetella, and Salmonella. These results demonstrate that the serological assays relying on the use of H. pylori PK-treated cells possessing a highly antigenic epitope are potentially useful as a serodiagnostic test for H. pylori infection.     

Synthesis,Docking Studies and Evaluation of Chalcones as Anti-Helicobacter pylori and antitumoral Agents

Helicobacter pylori colonizes the gastric epithelium of 50 % of world population and it is the main etiological agent of human chronic gastritis, peptic ulcer, and gastric cancer. In this study, we synthesized and characterized a series of 14 chalcones and evaluated their anti-H. pylori, NO inhibition (in vitro and in silico), and AGS cells cytotoxic effects. Compounds 3b and 3h showed MIC of 8 μg/mL. We observed structure-activity relationships, mainly related to the influence of methoxy substituent at C-2 ( 3b ) and the nitro group at C-4 ( 3h ) in chalcone scaffold. The fourteen chalcones inhibited the NO production in LPS-stimulated macrophages and showed potential for interaction on the active site of the iNOS enzyme. Finally, 3b and 3h showed the highest selectivity to the AGS cell lines. Thus, ours results suggest 3b and 3h as potential candidates for design of new and effective agents against H. pylori and related diseases.     

胃溃疡、胃癌组织中幽门螺杆菌及真菌基因片段的扩增分析

探讨胃溃疡、胃癌组织中幽门螺杆菌(Helicobacter pylori,Hp)、真菌(Fungi)单纯感染及混合感染的可能性并进行验证。应用聚合酶链反应(PCR)技术,分别自4例胃溃疡和4例胃癌并伴单纯幽门螺杆菌、真菌及其混合感染病例石蜡包埋组织(FFPE)中扩增Hp及fungi基因特异片段并进行测序分析。成功提取了FF-PE胃组织基因组DNA,并扩增出Hp 16S rRNA及真菌内转录间隔区18S rDNA基因和28S rDNA之间的基因特异条带,测序大小分别为114 bp和357 bp,经在线BLAST比对分析表明所扩增基因与Hp及真菌核苷酸具有高度同源性。胃溃疡、胃癌组织中存在Hp和真菌单纯感染及混合感染。推测Hp与真菌混合感染可能是加重胃溃疡发展和诱发胃癌发生的又一致病因素。积极治疗Hp与真菌混合感染有助于提高胃溃疡的治愈率和减少胃癌的发生。     

Helicobacter pylori from Gastric Cancer and Duodenal Ulcer Show Same Phylogeographic Origin in the Andean Region in Colombia

Background

A recent report has shown that the phylogenetic origin of Helicobacter pylori based on multi-locus sequence typing (MLST) was significantly associated with the severity of gastritis in Colombia. However, the potential relationship between phylogenetic origin and clinical outcomes was not examined in that study. If the phylogenetic origin rather than virulence factors were truly associated with clinical outcomes, identifying a population at high risk for gastric cancer in Colombia would be relatively straightforward. In this study, we examined the phylogenetic origins of strains from gastric cancer and duodenal ulcer patients living in Bogota, Colombia.

Methods

We included 35 gastric cancer patients and 31 duodenal ulcer patients, which are considered the variant outcomes. The genotypes of cagA and vacA were determined by polymerase chain reaction. The genealogy of these Colombian strains was analyzed by MLST. Bacterial population structure was analyzed using STRUCTURE software.

Results

H. pylori strains from gastric cancer and duodenal ulcer patients were scattered in the phylogenetic tree; thus, we did not detect any difference in phylogenetic distribution between gastric cancer and duodenal ulcer strains in the hpEurope group in Colombia. Sixty-six strains, with one exception, were classified as hpEurope irrespective of the cagA and vacA genotypes, and type of disease. STRUCTURE analysis revealed that Colombian hpEurope strains have a phylogenetic connection to Spanish strains.

Conclusions

Our study showed that a phylogeographic origin determined by MLST was insufficient for distinguishing between gastric cancer and duodenal ulcer risk among hpEurope strains in the Andean region in Colombia. Our analysis also suggests that hpEurope strains in Colombia were primarily introduced by Spanish immigrants.