Oyuntsetseg, Khasag
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Товч нэр
Oyuntsetseg, Khasag
Бүтэн нэр
Oyuntsetseg Khasag
Латин нэр
Oyuntsetseg Khasag
Албан тушаал
Судлаач
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Item type:Publication, IDDF2023-ABS-0237 Characteristics of helicobacter pylori from mongolia where burdening high incidence of gastric cancer(2023-06-01); ; ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, IDDF2023-ABS-0226 Initial results of screening program in mongolia where burdening high gastric cancer(2023-06-01); ; ; Background Mongolia is the leading country in the incidence and mortality rate of gastric cancer. According to the national data, TNM stage at the time of cancer diagnosis, a gastric cancer diagnosis is 0.4% in the carcinoma-in-situ stage, 5.1% in stage I, 15.2% in stage II, 42.7% in stage III and 36.5% in stage IV 36.5% were diagnosed respectively. Whereas almost 80% of people are diagnosed with early-stage of gastric cancer in Japan and Korea, where national cancer screening programs have been initiated for several decades. In 2022 national cancer screening program for upper gastrointestinal neoplasia was initiated; therefore, we aimed to conduct a multi-center study to determine gastric cancer incidence among the Mongolian population. Methods The cross-sectional study was performed to examine the detection rate of gastric cancer cases based on a national screening program from May to December 2022. The primary outcomes of this study were to define the detection rate (proportion of positive cases among individuals who underwent endoscopic screening) and to determine the characteristics of the cancer type, including its precursor disease based on histological examination. Results During the screening program, a total of 34581 participants’ data were collected from 28 endoscopy centers from Ulaanbaatar city and the western eastern, southern, and northern parts of the Mongolian province’s hospitals. The age range of the study participants was 35 to 93 years old. In terms of gender, 56.8% are men and 43.13% are women. The mean with SD age of people diagnosed with gastric cancer was 61.56±1.11, while the mean with SD age of healthy people was 53.84 ± 0.29 (p-value 0.0001). Among them, 113 (0.1%) patients were diagnosed with gastric cancer. The proportion of early-stage gastric cancer cases was 34 (30%) based on endoscopic and histological evaluation. The overall cases included in the national screening program are summarized in Figure 1 (IDDF2023-ABS-0226 Figure 1. Initial result from the national screening program for gastric cancer). Conclusions The initiation of the Mongolian national gastric cancer screening program could increase to detect the proportion of gastric cancer in its early stage. Therefore, screening programs should be continuous further. However, the quality of endoscopic examination should be improved. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Randomized Controlled Trial Comparing Standard Triple and Sequential Regimens for Helicobacter pylori Eradication(Mongolian National University of Medical Sciences, 2016-11-25); ; ; ; Objectives: The aim of this study was to compare effectiveness of sequential therapy to the standard triple therapy to eradicate Helicobacter pylori (H. pylori) in Mongolia. Methods: From September 2014 to February 2016, 140 patients with confirmed H. pylori infection (upper gastrointestinal tract (GI) endoscopy, rapid urease test, histology, H. pylori stool antigen test (HpStAg)) randomly received 10 days standard triple therapy (20 mg pantoprazole, 1 g amoxicillin, 500 mg clarithromycin, all twice daily for 10 days; STT group, n = 70), and sequential therapy (20 mg pantoprazole, 1 g amoxicillin twice daily for 5 days followed by 20 mg pantoprazole, 500 mg clarithromycin, 500 mg metronidazole twice daily for 5 days; SQT group, n = 70). Successful eradication therapy for H. pylori infection was defined as a negative HpStAg test 4 weeks after the end of eradication treatment. Results: The eradication rates by intention to treat (ITT) analysis were 71.4% (50/70) and 50% (35/70) in the STT and SQT groups, respectively (p = 0.033). The eradication rates by per-protocol (PP) analysis were 72.5% (50/69) and 51.5% (35/68) in the STT and SQT groups, respectively (p = 0.018). The adverse event rates were 7.6% (5/70) and 18.6% (13/70) in the STT and SQT groups, respectively (p = 0.043). Conclusion: The eradication rate was significantly higher in the STT group compared with the SQT group. But the eradication efficacies of both STT and SQT for H. pylori infection in Mongolia are unacceptable. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Initial Trials With Susceptibility-Based and Empiric Anti-H. pylori Therapies in Mongolia(Frontiers Media SA, 2019); ; ; ; Background: Mongolia has a high prevalence of Helicobacter pylori infection and gastric cancer. We conducted a prospective, randomized, single-blind study to evaluate the efficacy of common regimens in Mongolia and to obtain specimens for susceptibility testing. Methods: Empiric treatments: 270 patients with confirmed H. pylori infection were randomized to receive 10 days clarithromycin-triple therapy (Clari-TT) (n = 90), modified bismuth quadruple therapy (M-BQT) (n = 90), or sequential therapy (ST) (n = 90). A second group of 46 patients received susceptibility-based Clari-TT. H. pylori was cultured from 131 patients and susceptibility testing was performed. H. pylori eradication was confirmed by stool antigen 4 weeks after the therapy. Results: Intention-to-treat (ITT) analysis cure rates were 71.1% (95% CI = 61.7-80.5%) for Clari-TT, 87.8% (95% CI = 81-94.6%) for M-BQT, 67.8% (95% CI = 58.1-77.5%) for ST vs. 89.1% (95% CI = 86-98.2%) for susceptibility-based Clari-TT. Per-protocol (PP) analysis results for these therapies were 72.7% (63.4-82%), 89.8% (83.5-96.1%), 68.5% (58.8-78.2%), and 97.6% (89.5-99.8%), respectively. Among 131 cultured H. pylori, resistance rates to amoxicillin, clarithromycin, and metronidazole were 8.4, 37.4, and 74%, respectively. Conclusion: In Mongolia, the prevalence of H. pylori resistance is high requiring bismuth quadruple therapy or susceptibility-based therapy to obtain acceptable cure rates.Scopus© Citations 12 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, High Antibiotic Resistance of Helicobacter pylori and Its Associated Novel Gene Mutations among the Mongolian Population(MDPI AG, 2020-07); ; ; Matsumoto, TakashiMongolia has a high prevalence of Helicobacter pylori infection and the second highest incidence of gastric cancer worldwide. Thus, investigating the prevalence of antibiotic resistance and its underlying genetic mechanism is necessary. We isolated 361 H. pylori strains throughout Mongolia. Agar dilution assays were used to determine the minimum inhibitory concentrations of five antibiotics; amoxicillin, clarithromycin, metronidazole, levofloxacin, and minocycline. The genetic determinants of antibiotic resistance were identified with next-generation sequencing (NGS) and the CLC Genomics Workbench. The resistance to metronidazole, levofloxacin, clarithromycin, amoxicillin, and minocycline was 78.7%, 41.3%, 29.9%, 11.9% and 0.28%, respectively. Multidrug resistance was identified in 51.3% of the isolates investigated which were further delineated into 9 antimicrobial resistance profiles. A number of known antibiotic resistance mutations were identified including rdxA, frxA (missense, frameshift), gyrA (N87K, A88P, D91G/N/Y), 23S rRNA (A2143G), pbp1A (N562Y), and 16S rRNA (A928C). Furthermore, we detected previously unreported mutations in pbp1A (L610*) and the 23S rRNA gene (A1410G, C1707T, A2167G, C2248T, and C2922T). The degree of antibiotic resistance was high, indicating the insufficiency of standard triple therapy in Mongolia.Scopus© Citations 36 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Western-Type Helicobacter pylori CagA are the Most Frequent Type in Mongolian Patients(MDPI AG, 2019-05); ; Bolor, DashdorjHelicobacter pylori infection possessing East-Asian-type CagA is associated with carcinogenesis. Mongolia has the highest mortality rate from gastric cancer. Therefore, we evaluated the CagA status in the Mongolian population. High risk and gastric cancer patients were determined using endoscopy and histological examination. H. pylori strains were isolated from different locations in Mongolia. The CagA subtypes (East-Asian-type or Western-type, based on sequencing of Glu-Pro-Ile-Tyr-Ala (EPIYA) segments) and vacA genotypes (s and m regions) were determined using PCR-based sequencing and PCR, respectively. In total, 368 patients were examined (341 gastritis, 10 peptic ulcer, and 17 gastric cancer). Sixty-two (16.8%) strains were cagA-negative and 306 (83.1%) were cagA-positive (293 Western-type, 12 East-Asian-type, and one hybrid type). All cagA-negative strains were isolated from gastritis patients. In the gastritis group, 78.6% (268/341) had Western-type CagA, 2.9% (10/341) had East-Asian-type, and 18.2% (61/341) were cagA-negative. However, all H. pylori from gastric cancer patients possessed Western-type CagA. Histological analyses showed that East-Asian-type CagA was the most virulent strains, followed by Western-type and cagA-negative strains. This finding agreed with the current consensus. CagA-positive strains were the most virulent type. However, the fact that different CagA types can explain the high incidence of gastric cancer might be inapplicable in Mongolia.Scopus© Citations 21 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Study of Helicobacter pylori Isolated from a High-Gastric-Cancer-Risk Population: Unveiling the Comprehensive Analysis of Virulence-Associated Genes including Secretion Systems, and Genome-Wide Association Study(MDPI AG, 2023-09); ; ; Khangai, AyushBACKGROUND: The prevalence of gastric cancer in Mongolia, in East Asia, remains the highest in the world. However, most Helicobacter pylori strains in Mongolia have a less virulent Western-type CagA. We aimed to determine how H. pylori genomic variation affected gastric diseases, especially gastric cancer, based on comprehensive genome analysis. METHODS: We identified a set of 274 virulence-associated genes in H. pylori, including virulence factor and outer membrane protein (OMP) genes, the type four secretion system gene cluster, and 13 well-known virulence gene genotypes in 223 H. pylori strains and their associations with gastric cancer and other gastric diseases. We conducted a genome-wide association study on 158 H. pylori strains (15 gastric cancer and 143 non-gastric cancer strains). RESULTS: Out of 274 genes, we found 13 genes were variable depending on disease outcome, especially iron regulating OMP genes. H. pylori strains from Mongolia were divided into two main subgroups: subgroup (Sg1) with high risk and Sg2 with low risk for gastric cancer. The general characteristics of Sg1 strains are that they possess more virulence genotype genes. We found nine non-synonymous single nucleotide polymorphisms in seven genes that are linked with gastric cancer strains. CONCLUSIONS: Highly virulent H. pylori strains may adapt through host-influenced genomic variations, potentially impacting gastric carcinogenesis.Scopus© Citations 10 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Exploring Alternative Treatment Choices for Multidrug-Resistant Clinical Strains of Helicobacter pylori in Mongolia(MDPI AG, 2023-11); ; Helicobacter pylori is a pathogen related to severe diseases such as gastric cancer; because of rising antimicrobial-resistant strains, failure to eradicate H. pylori with antibiotics has increased worldwide. Multidrug-resistant H. pylori and gastric cancer is common in Mongolia; therefore, we aimed to explore alternative antimicrobial treatments and the genomes of resistant strains in this country. A total of 361 H. pylori strains isolated from patients in Mongolia were considered. Minimal inhibitory concentrations for two fluoroquinolones (ciprofloxacin and moxifloxacin), rifabutin, and furazolidone were determined via two-fold agar dilution. Genomic mutations in antibiotic-resistant strains were identified by next-generation sequencing using the Illumina Miseq platform and compared with genes from a reference H. pylori strain (26695). The resistance rate of H. pylori strains to quinolones was high (44% to ciprofloxacin and 42% to moxifloxacin), and resistance to rifabutin was low (0.5%); none were resistant to furazolidone. Most quinolone-resistant strains possessed gyrA gene mutations causing amino acid changes (e.g., N87K, A88P, and D91G/Y/N). While one rifabutin-resistant strain had amino acid-substituting mutations in rpoB (D530N and R701C), the other had three novel rpoB mutations; both rifabutin-resistant strains were sensitive to furazolidone. Overall, our findings suggest that rifabutin and/or furazolidone may be an alternative, effective H. pylori treatment in patients who have failed to respond to other treatment regimens.Scopus© Citations 3 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, The prevalence of Helicobacter pylori infection and other risk factors among Mongolian dyspeptic patients who have a high incidence and mortality rate of gastric cancer(Springer Science and Business Media LLC, 2018); ; ; ; Dashdorj, AzzayaBACKGROUND: Mongolia has not only the second highest incidence rate but also the highest mortality rate for gastric cancer globally. In addition to gastric cancer, ulcerative disease complications are also life threatening; thus, investigating Helicobacter pylori infection and other risk factors is essential. RESULTS: H.pylori infection was high in tested dyspeptic patients from all parts of Mongolia, with an overall infection rate of 80.0%. Logistic regression analysis showed that H. pylori infection was associated with gastritis (odds ratio; 9.0 ([95% confidence interval 5.0-16.2]); p < 0.0001). H. pylori infection (3.3 [2.0-5.4]; p < 0.0001) and > 40 years old (1.5 [1.0-2.0]; p < 0.02) were both associated with atrophy. However, > 40 years old (3.8 [2.4-6.0]; p < 0.0001) and high salt intakes (1.6 [1.0-2.3]; p < 0.02), but not H. pylori infection, were associated with intestinal metaplasia. Excessive amount of salt usage was dramatically higher in northern and western parts of Mongolia, where precancerous diseases, such as erosive esophagitis (for cardia cancer), severe atrophy, and intestinal metaplasia (for non-cardia cancer), were highly prevalent. CONCLUSIONS: H. pylori infection was the major gastric health problem among the Mongolian population. In addition, environmental factors such as high salt intake worsened the clinical outcome. Therefore, a nationwide screening and eradication of H. pylori infection as well as salt-reducing measures should be implemented.Scopus© Citations 27 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, New observations regarding Helicobacter pylori and gastric cancer in Mongolia(Wiley, 2018-08); ; Scopus© Citations 15