scholarly journals Pathogenesis ofHelicobacter pylori-Related Gastroduodenal Diseases from Molecular Epidemiological Studies

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Yoshio Yamaoka
Keyword(s):  
Gastric Cancer ◽  
Virulence Factors ◽  
Epidemiological Studies ◽  
Sequencing Technology ◽  
Disease Spectrum ◽  
Genome Wide ◽  
A Genome ◽  
High Prevalence ◽  
Different Types ◽  
H Pylori

Helicobacter pyloriis a major human pathogen that infects the stomach and produces inflammation that is responsible for various gastroduodenal diseases. Despite the high prevalence ofH. pyloriinfections in Africa and South Asia, the incidence of gastric cancer in these areas is much lower than in other countries. The incidence of gastric cancer also tends to decrease from north to south in East Asia. Data from molecular epidemiological studies show that this variation in different geographic areas could be explained in part by different types ofH. pylorivirulence factors, especially CagA, VacA, and OipA.H. pyloriinfection is thought to be involved in both gastric cancer and duodenal ulcer, which are at opposite ends of the disease spectrum. This discrepancy can also be explained in part by anotherH. pylorifactor, DupA, as well as by CagA typing (East Asian type versus Western type).H. pylorihas a genome of approximately 1,600 genes; therefore, there might be other novel virulence factors. Because genome wide analyses using whole-genome sequencing technology give a broad view of the genome ofH. pylori, we hope that next-generation sequencers will enable us to efficiently investigate novel virulence factors.

scholarly journals High Prevalence ofHelicobacter pylori hopQII Genotype Isolated from Iranian Patients with Gastroduodenal Disorders

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Amin Talebi Bezmin Abadi ◽  
Ashraf Mohabbati Mobarez
Keyword(s):  
Gastric Cancer ◽  
Virulence Factors ◽  
Outer Membrane Proteins ◽  
Type Ii ◽  
Specific Pcr ◽  
Geographical Regions ◽  
High Prevalence ◽  
H Pylori ◽  
Gastric Cancer Patients ◽  
Gastroduodenal Disorders

Helicobacter pyloriplays an important role in the pathogenesis of chronic gastritis, peptic ulceration, and noncardia gastric cancer. Several putative virulence factors forH. pylorihave been identified includingvacA,babA, andiceA. HopQ is one of the outer membrane proteins involved in bacterial adherence to gastric mucosa and has been suggested to also play a role in the virulence ofH. pylori. Due to the substantial geographic differences in the prevalence ofH. pylorivirulence factors reported, the main purpose of the current study was to investigate the association between differentH. pylorivirulencehopQalleles (types I and II) and patients with gastroduodenal disorders. The presence ofH. pyloriandhopQalleles in gastric biopsy specimens was identified by specific PCR assays.H. pyloritype IIhopQwas found to be significantly associated with gastric cancer patients (odds ratio: 3.47, 95% CI: 1.56–5.89). Information about the prevalence ofH. pylori hopQtype II can be used for determining the high-risk diseases type which is actually colonized byH. pylori hopQtype II positive strains. The presence ofH. pylori hopQtype II should be investigated in different geographical regions as confirmatory findings may provide a definite biomarker attributed to the pathogenesis of certain severe digestive diseases.

scholarly journals Helicobacter pylori Virulence Factors—Mechanisms of Bacterial Pathogenicity in the Gastric Microenvironment

Cells ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 27
Author(s):  
Jacek Baj ◽  
Alicja Forma ◽  
Monika Sitarz ◽  
Piero Portincasa ◽  
Gabriella Garruti ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Helicobacter Pylori ◽  
Gastric Mucosa ◽  
Virulence Factors ◽  
Premalignant Lesions ◽  
Bacterial Pathogenicity ◽  
Current State ◽  
Genetic And Environmental Factors ◽  
H Pylori ◽  
Stimulation Of

Gastric cancer constitutes one of the most prevalent malignancies in both sexes; it is currently the fourth major cause of cancer-related deaths worldwide. The pathogenesis of gastric cancer is associated with the interaction between genetic and environmental factors, among which infection by Helicobacter pylori (H. pylori) is of major importance. The invasion, survival, colonization, and stimulation of further inflammation within the gastric mucosa are possible due to several evasive mechanisms induced by the virulence factors that are expressed by the bacterium. The knowledge concerning the mechanisms of H. pylori pathogenicity is crucial to ameliorate eradication strategies preventing the possible induction of carcinogenesis. This review highlights the current state of knowledge and the most recent findings regarding H. pylori virulence factors and their relationship with gastric premalignant lesions and further carcinogenesis.

scholarly journals Special Issue “H. pylori Virulence Factors in the Induction of Gastric Cancer”

Toxins ◽  
2018 ◽  
Vol 10 (5) ◽  
pp. 176 ◽  
Author(s):  
Jean Crabtree ◽  
Silja Wessler
Keyword(s):  
Gastric Cancer ◽  
Virulence Factors ◽  
Special Issue ◽  
H Pylori

Prevalence of Dystonia in Antioquia, Colombia

2016 ◽  
Vol 46 (2) ◽  
pp. 137-143 ◽  
Author(s):  
Juan Marcos Solano Atehortúa ◽  
Sandra Patricia Isaza Jaramillo ◽  
Ana Rendón Bañol ◽  
Omar Buritica Henao
Keyword(s):  
Epidemiological Studies ◽  
Demographic Characteristics ◽  
Linear Modeling ◽  
Delay In Diagnosis ◽  
True Prevalence ◽  
High Prevalence ◽  
The World ◽  
Different Types ◽  
Capture Recapture ◽  
Log Linear

Background: There are few published epidemiological studies concerning dystonia. Its true prevalence has been difficult to establish. There is no data published in Latin America on this matter. Methods: In this study the prevalence of dystonias in the Department of Antioquia (Colombia) was estimated using a capture-recapture methodology with log-linear modeling, including cases in 3 centers for neurological referrals that cover the Department of Antioquia from 2007 to 2012. Results: The overall prevalence was 712 per 1,000,000 (95% CI 487-937). Of the total of 874 patients, 79% had primary dystonias, and 75.5% had focal dystonias. The delay in diagnosis was longer for primary dystonias, with a median of 1 year. Conclusion: We found a high prevalence of dystonias in Antioquia. The frequency of the different types of dystonias, as well as the demographic characteristics of our patients, is similar to data from other populations of the world.

scholarly journals Prevalence of Helicobacter pylori vacA, cagA, cagE1, cagE2, dupA and oipA Genotypes in Patients With Gastrointestinal Diseases

2020 ◽  
Author(s):  
Hossein Masoumi Asl ◽  
Ali Badamchi ◽  
Shima Javadinia ◽  
Siamak Khaleghi ◽  
Leila Tehraninia ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Helicobacter Pylori ◽  
Gastrointestinal Diseases ◽  
Cancer Group ◽  
Urease Test ◽  
High Prevalence ◽  
Vaca Gene ◽  
H Pylori ◽  
Positive Results ◽  
Gastroenterology Unit

Helicobacter pylori (H. pylori) is a bacterium that resides in the human stomach, which is associated with gastroduodenal diseases. We investigate the prevalence of cagA, vacA, oipA, cagE1, cagE2 and dupA genotypes in H. pylori isolated from patients with Gastric ulcer, duodenal ulcer, and Gastric Cancer. Collected 74 samples from the Gastroenterology Unit of the Rasool Akram Hospital were included in this study. Gastric disorders were identified by endoscopy .gastric cancer was further confirmed by histopathology. H. pylori were detected by the urease test. Subsequently, DNA was extracted from gastric tissue of the subjects with the CLO-test yielded positive results. In general, 74 patients with a mean age of 53.45 years (Range 22 to 86-year-old), including 45 men and 29 women, were studied. Among 74 H. pylori-positive patients, 70 (94.5%) patients were positive for the cagA gene. About 95.8% (23/24) of the patients with gastric carcinoma were dupA positive and VacA gene (91.8%). The oipA genotype was detected in 71 (96%) of H.pylori positive samples. This gene was more common in patients with gastritis rather than cancer group. Also, 97.2% of 74 H. pylori isolates were cagE2-positive. In 25 patients with PUD, the occurrence percent of cagA+/VacA+, cagA+/Vac- , cagA- /VacA+ and cagA- /VaxA- genotypes were found 80%, 12%, 4.2% and 4.2 respectively. The results of the present study suggest that a high prevalence of virulent factors could contribute to the risk of developing gastroduodenal diseases.

scholarly journals Elucidating the genetic architecture underlying IGF1 levels and its impact on genomic instability and cancer risk

2021 ◽  
Vol 6 ◽  
pp. 20
Author(s):  
Stasa Stankovic ◽  
Felix R. Day ◽  
Yajie Zhao ◽  
Claudia Langenberg ◽  
Nicholas J. Wareham ◽  
...  
Keyword(s):  
Genomic Instability ◽  
Genome Wide Association Study ◽  
Genetic Regulation ◽  
Epidemiological Studies ◽  
European Ancestry ◽  
Reverse Causality ◽  
Lung Cancers ◽  
Genome Wide ◽  
A Genome ◽  
The Uk

Background: Insulin-like growth factor-1 (IGF1) has been implicated in mitogenic and anti-apoptotic mechanisms that promote susceptibility to cancer development and growth. Previous epidemiological studies have described phenotypic associations between higher circulating levels of IGF1 in adults with higher risks for breast, prostate, ovarian, colorectal, melanoma and lung cancers. However, such evidence is prone to confounding and reverse causality. Furthermore, it is unclear whether IGF1 promotes only the survival and proliferation of cancerous cells, or also the malignant transformation of healthy cells. Methods: We perform a genome-wide association study in 428,525 white European ancestry individuals in the UK Biobank study (UKBB) and identify 831 independent genetic determinants of circulating IGF1 levels, double the number previously reported. Results: Collectively these signals explain ~7.5% of the variance in circulating IGF1 levels in EPIC-Norfolk, with individuals in the highest 10% of genetic risk exhibiting ~1 SD higher levels than those in the lowest 10%. Using a Mendelian randomization approach, we demonstrate that genetically higher circulating IGF1 levels are associated with greater likelihood of mosaic loss of chromosome Y in leukocytes in men in UKBB (OR per +1 SD = 1.038 (95% CI: 1.010-1.067), P=0.008) and 23andMe, Inc. (P=6.8×10-05), a biomarker of genomic instability involved in early tumorigenesis. Genetically higher IGF1 is also associated with higher risks for colorectal (OR = 1.126 (1.048-1.210), P=1.3×10-03) and breast cancer (OR= 1.075 (1.048-1.103), P=3.9×10-08), with similar effects on estrogen positive (ER+) (OR = 1.069 (1.037-1.102), P=2.3×10-05) and estrogen negative (ER-) (OR = 1.074 (1.025-1.125), P=3.9×10-08) subtypes. Conclusions: These findings give an insight into the genetic regulation of circulating IGF1 levels and support a causal role for IGF1 in early tumorigenesis and risks for breast and colorectal cancers.

scholarly journals Analysis of the clinical significance of DNA methylation in gastric cancer based on a genome-wide high-resolution array

2019 ◽  
Vol 11 (1) ◽  
Author(s):  
Wen-Liang Fang ◽  
Ming-Huang Chen ◽  
Kuo-Hung Huang ◽  
Shih-Ching Chang ◽  
Chien-Hsing Lin ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Dna Methylation ◽  
Disease Free Survival ◽  
Plasma Samples ◽  
Free Survival ◽  
Genome Wide ◽  
A Genome ◽  
Disease Free Survival Rate ◽  
Disease Free ◽  
Hypermethylated Genes

Abstract Background Aberrant DNA methylation is involved in gastric carcinogenesis and may serve as a useful biomarker in the diagnosis and detection of gastric cancer (GC) recurrence. Results A total of 157 patients who received surgery for GC were enrolled in the present study. A genome-wide methylation analysis was performed in tumor and adjacent normal tissues for the discovery set of 16 GC patients; the top three hypermethylated CpG sites of DNA promoters were selected for validation in tissue and plasma samples for the validation set of 141 GC patients. The frequencies of the top three hypermethylated genes in available patient tissues (n = 141) and plasma samples (n = 106) were 41.8% and 38.7%, respectively, for ADAM19; 40.4% and 42.5%, respectively, for FLI1; and 56.7% and 50.9%, respectively, for MSC. In both tissue and plasma samples, FLI1 hypermethylation was associated with more advanced GC and liver and distant lymphatic metastasis, and ADAM19 hypermethylation was associated with more stage IV GC. In plasma samples, MSC hypermethylation was more common in non-superficial type GC than samples without MSC hypermethylation. In both tissue and plasma samples, patients with methylation of all the three genes had significantly more liver metastases, distant lymphatic metastases, and paraaortic lymph node metastases than patients with two or fewer hypermethylated genes. The survival analysis showed that only for stage III GC, patients with hypermethylation of two or three genes had a worse 5-year disease-free survival rate than those with hypermethylation of one or none of the three genes. Subgroup analysis showed that FLI1 hypermethylation in both tissue and plasma samples was associated with liver metastasis in MSI−/EBV− GC, and MSC hypermethylation in tissue samples was correlated with liver metastasis in MSI+ or EBV+ GC. Patients with FLI1 hypermethylation in plasma samples had a significantly worse 5-year disease-free survival rate than those without FLI1 hypermethylation in MSI−/EBV− GC. FLI1 hypermethylation was an independent prognostic factor affecting the overall survival and disease-free survival in both tissue and plasma samples. Conclusions DNA methylation is a useful biomarker for predicting tumor recurrence patterns and GC patient survival.

scholarly journals Recent Molecular Evolution of Human Metapneumovirus (HMPV): Subdivision of HMPV A2b Strains

2020 ◽  
Vol 8 (9) ◽  
pp. 1280
Author(s):  
Naganori Nao ◽  
Miwako Saikusa ◽  
Ko Sato ◽  
Tsuyoshi Sekizuka ◽  
Shuzo Usuku ◽  
...  
Keyword(s):  
Respiratory Infections ◽  
Epidemiological Studies ◽  
Human Metapneumovirus ◽  
Evolutionary Relationships ◽  
Acute Respiratory Infections ◽  
Evolutionary Analysis ◽  
The Novel ◽  
Genome Wide ◽  
A Genome

Human metapneumovirus (HMPV) is a major etiological agent of acute respiratory infections in humans. HMPV has been circulating worldwide for more than six decades and is currently divided into five agreed-upon subtypes: A1, A2a, A2b, B1, and B2. Recently, the novel HMPV subtypes A2c, A2b1, and A2b2 have been proposed. However, the phylogenetic and evolutionary relationships between these recently proposed HMPV subtypes are unclear. Here, we report a genome-wide phylogenetic and evolutionary analysis of 161 HMPV strains, including unique HMPV subtype A2b strains with a 180- or 111-nucleotide duplication in the G gene (nt-dup). Our data demonstrate that the HMPV A2b subtype contains two distinct subtypes, A2b1 and A2b2, and that the HMPV subtypes A2c and A2b2 may be different names for the same subtype. HMPV A2b strains with a nt-dup also belong to subtype A2b2. Molecular evolutionary analyses indicate that subtypes A2b1 and A2b2 diverged from subtype A2b around a decade after the subtype A2 was divided into the subtypes A2a and A2b. These data support the A2b1 and A2b2 subtypes proposed in 2012 and are essential for the unified classification of HMPV subtype A2 strains, which is important for future HMPV surveillance and epidemiological studies.

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