Search Results (866)

Objective: To analyze the composition of the oral microbiome in periodontal pocket lesions and on the tongue dorsum of patients with Helicobacter pylori-associated gastric disease. Materials and Methods: Patients diagnosed with gastric disease and H. pylori (HP+) were evaluated in comparison to a control group of H. pylori-negative patients without gastric disease (HP−). Periodontal and oral health clinical parameters (PPD, BoP, PSE, plaque score and modified DMFT) were assessed for each patient. Microbiological samples were collected from the deepest periodontal pockets and tongue dorsum, followed by DNA extraction, 16S rRNA PCR amplification, and Next-Generation-Sequencing (NGS) analyses. Results: Sixty-seven patients (27F; 40M, aged 35–85 years) were enrolled. Of these, 52 were HP+ and 15 were HP−. HP+ patients exhibited a significantly higher presence of decayed teeth (p < 0.05) and slightly fewer missing teeth (p > 0.05). The plaque score was significantly higher in HP+ patients (p < 0.05), while PPD and BoP showed no significant differences (p > 0.05). NGS analysis revealed no presence of H. pylori in any samples of both periodontal and tongue sites. HP+ patients showed a distinct microbial composition, including higher prevalence of Capnocytophaga, Fusobacterium, and Peptostreptococcus genera in both locations (pockets and tongue dorsum). Conclusions: The study demonstrated that HP+ patients exhibit distinct oral microbial profiles compared to HP− patients, especially in areas with deeper periodontal pockets. H. pylori was not detected in the oral microbiomes of either group. Full article

Background/Objectives: Helicobacter pylori (H. pylori) is a common gastric pathogen linked to gastritis, gastroduodenal ulcers, and gastric cancer. Rising antimicrobial resistance (AMR) poses challenges for effective treatment and has prompted the WHO to classify H. pylori as a high-priority pathogen. This study aimed to detect the prevalence of AMR genes in H. pylori-positive gastric samples from patients in Algarve, Portugal, where regional data is scarce. Methods: Eighteen H. pylori-positive gastric biopsy samples from patients undergoing upper gastrointestinal endoscopy were analyzed. PCR and sequencing were used to identify genes associated with resistance to amoxicillin (Pbp1A), metronidazole (rdxA, frxA), tetracycline (16S rRNA mutation) and clarithromycin (23S rRNA). Sequence identity and homologies were verified using tBLASTx and the Comprehensive Antibiotic Resistance Database (CARD). Results: Out of the 18 H. pylori-positive samples, 16 (88.9%) contained at least one AMR gene. The most frequent genes were rdxA (83.3%) and frxA (66.7%) for metronidazole resistance, and the 16S rRNA mutation (66.7%) for tetracycline. Resistance to amoxicillin and clarithromycin was detected in 27.8% and 16.7% of cases, respectively. Most samples (72.2%) had multiple resistance genes. A significantly strong association was found between female sex and the presence of the rdxA gene (p = 0.043). Conclusions: The study reveals a high prevalence of H. pylori resistance genes in Algarve, particularly against metronidazole and tetracycline. These findings highlight the need for local surveillance and tailored treatment strategies. Further research with larger populations is warranted to assess regional resistance patterns and improve eradication efforts. Full article

Cancer disparities in low- and middle-income countries (LMICs) arise from multifaceted interactions between environmental exposures, infectious agents, and systemic inequities, such as limited access to care. The exposome, a framework encompassing the totality of non-genetic exposures throughout life, offers a powerful lens for understanding these disparities. In LMICs, populations are disproportionately affected by air and water pollution, occupational hazards, and oncogenic infections, including human papillomavirus (HPV), hepatitis B virus (HBV), Helicobacter pylori (H. pylori), human immunodeficiency virus (HIV), and neglected tropical diseases, such as schistosomiasis. These infectious agents contribute to increased cancer susceptibility and poor outcomes, particularly in immunocompromised individuals. Moreover, climate change, food insecurity, and barriers to healthcare access exacerbate these risks. This review adopts a population-level exposome approach to explore how environmental and infectious exposures intersect with genetic, epigenetic, and immune mechanisms to influence cancer incidence and progression in LMICs. We highlight the critical pathways linking chronic exposure and inflammation to tumor development and evaluate strategies such as HPV and HBV vaccination, antiretroviral therapy, and environmental regulation. Special attention is given to tools such as exposome-wide association studies (ExWASs), which offer promise for exposure surveillance, early detection, and public health policy. By integrating exposomic insights into national health systems, especially in regions such as sub-Saharan Africa (SSA) and South Asia, LMICs can advance equitable cancer prevention and control strategies. A holistic, exposome-informed strategy is essential for reducing global cancer disparities and improving outcomes in vulnerable populations. Full article

Gastric cancer traditionally affects older adults, and its precursor lesions and risk factors are well-documented in this population. Helicobacter pylori (H. pylori) infection remains highly prevalent in Saudi Arabia and contributes to gastric pathology. However, early-onset gastric cancer (EOGC), diagnosed in individuals aged ≤ 45 years, presents unique challenges and remains poorly understood in young populations. Therefore, we conducted an observational cohort study using a prospective longitudinal design (2021–2024) involving 1823 Saudi nationals aged 18–45 years who underwent zoom high-definition chromoendoscopy to evaluate the prevalence of premalignant gastric lesions (PGLs) and EOGC. We found a high H. pylori prevalence (78.0%) with PGLs in 1.9% of participants and EOGC-adenocarcinoma in 0.7% of patients. All EOGC cases arose from dysplasia, with most PGLs being classified as OLGA/OLGIM stage II/III. Multiple risk factorswere significantly associated with PGLs and EOGC, including H. pylori infection (p = 0.022), increasing age (p < 0.001), a family history of gastric cancer (p < 0.001), poor dietary habits (p < 0.001), obesity (p < 0.001), and smoking (p < 0.001). Additional EOGC risk factors include dage of 36–45 years (p = 0.018), EBV infection (p = 0.016), and diabetes mellitus (p = 0.001). These findings demonstrate the notable presence of PGLs and EOGC in young Saudi adults and emphasize the importance of early detection and risk factor management in this vulnerable population. Full article

Background: There has been a reduction in successful H. pylori eradication rates recently, which is largely attributed to increasing antibiotic resistance. In areas of high dual clarithromycin and metronidazole resistance such as ours, Maastricht VI/Florence guidelines recommend bismuth quadruple therapy (BQT) as first line of therapy; however, the availability of bismuth was poor in Ireland until recently. Similarly, tetracycline, a component of BQT, is restricted locally, with doxycycline (D) being approved and reimbursed for most indications. Aims: To assess the efficacy of BQT-D therapy for H. pylori eradication in an Irish cohort. Methods: All patients testing positive for H. pylori in three Irish referral centres by urea breath test, stool antigen, or histology were treated prospectively with BQT-D (bismuth subcitrate 120 mg QDS, metronidazole 400 mg TDS, doxycycline 100 mg BD and esomeprazole 40 mg BD) for 14 days. Eradication was evaluated with a urea breath test (UBT) >4 weeks after therapy cessation or by stool antigen testing, as available. Outcomes were recorded and analysed according to demographics and H. pylori treatment history of the patients. Results: 217 patients completed post-eradication testing. Of which, 124 (57%) were female, with a mean age 52 years. 180 patients (83%) were treatment-naïve. A total of 165/180 (92%) of the treatment-naïve patients had successful eradication. There was no association between eradication and gender or age in this cohort (p = 0.3091, p = 0.962 respectively). A total of 29 patients received this therapy as second-line therapy, of which 22 (76%) had successful eradication. Eight patients received the regimen as rescue therapy, with seven (88%) having successful eradication. No serious adverse events were reported. Eleven individuals (6.5%) commented on the complicated nature of the regimen, with 11 tablets being taken at five intervals daily. Conclusions: BQT-D as first-line therapy for H. pylori infection is highly effective in a high dual-resistance population, achieving >90% eradication. BQT-D as a second-line treatment performed less well. Our data support BQT-D as a first-line treatment. Full article

Helicobacter pylori, a spiral-shaped bacterium found in the stomach, is associated with various gastrointestinal and systemic health conditions. Effective suppression of H. pylori is therefore critical for managing gastrointestinal diseases. In a search for natural products with anti-H. pylori activity, the extract of Atractylodes macrocephala rhizoma showed significant inhibitory effects. Chromatographic purification of A. macrocephala extract yielded thirteen compounds, which were identified as ten sesquiterpenes and three polyacetylenes by spectroscopic analysis. The sesquiterpene compounds belong to the eudesmane or eudesmane lactone types and exhibited structure-dependent efficacy. The major eudesmane lactone sesquiterpene, atractylenolide I (1), showed strong inhibitory activity comparable to metronidazole, a positive control, and atractylenolide III (3) also showed good efficacy. However, structural modification such as hydroxylation, methylation, or acetylation of the sesquiterpenes led to reduced activity. In contrast, polyacetylene derivatives displayed only mild inhibitory effects. Further evaluation of the active compounds against three H. pylori strains such as 51, 43504, and 26695 showed that atractylenolide I (1) had potent inhibitory effects against all three strains, with MIC₅₀ values of ranging from 27.3 to 48.6 μM and MIC₉₀ values from 45.4 to 87.2 μM. Atractylenolide III (3) exhibited selective activity against strain 51 with MIC₅₀ value of 89.9 μM. Both compounds also exhibited anti-inflammatory activity with IC₉₀ values of 23.3 and 31.1 μM, respectively, although they showed little effect on urease. This is the first report on the anti-H. pylori efficacy of various constituents of A. macrocephala and comparative analysis of inhibitory effects against several strains, which will provide scientific evidence supporting its potential as therapeutic agent for H. pylori-related infection. Full article

Helicobacter pylori infection represents one of the most prevalent and persistent bacterial infections worldwide, closely linked to a spectrum of gastroduodenal diseases, including chronic gastritis, peptic ulceration, and gastric cancer. Recent advances have shed light on the critical role of endogenous lectins, particularly galectins, in modulating host–pathogen interactions within the gastric mucosa. Galectins are β-galactoside-binding proteins with highly conserved structures but diverse biological functions, ranging from regulation of innate and adaptive immunity to modulation of cell signaling, apoptosis, and epithelial integrity. This review provides a comprehensive synthesis of current knowledge on the involvement of key galectin family members—especially Galectin-1, -2, -3, -8, and -9—in the context of H. pylori infection. Their dual roles in enhancing mucosal defense and facilitating bacterial persistence are examined along with their contributions to immune evasion, inflammation, and gastric carcinogenesis. Understanding the interplay between galectins and H. pylori enhances our knowledge of mucosal immunity. This interaction may also reveal potential biomarkers for disease progression and identify novel therapeutic targets. Modulating galectin-mediated pathways could improve outcomes in H. pylori-associated diseases. Full article

H. pylori infects over half of the global population and is associated with various gastric and extra-gastric diseases. Other species, such as zoonotic non-Helicobacter pylori Helicobacters (NHPHs), have shown similar associations with gastritis and MALT lymphoma and H. pylori-negative cases with gastric disease have been identified, including gastric MALT lymphoma, chronic gastritis, and gastroduodenal ulcers. Accurate identification of these species is of great relevance but remains challenging using conventional diagnostic methods. This cross-sectional study aimed to determine the prevalence of H. pylori and NHPH infections, comparing standard histological protocols with molecular techniques. Between December 2024 and February 2025, 54 adult patients undergoing upper gastrointestinal endoscopy (UGE) with gastric biopsy in three hospitals in Algarve, Portugal were recruited. Endoscopic assessment was performed, and gastric biopsies were collected for histological and molecular analysis. DNA was extracted from antral biopsies and analyzed by conventional PCR to detect H. pylori and NHPH. H. pylori diagnostic techniques were compared, descriptive plus statistical analysis was performed, and p-values < 0.05 were considered to be statistically significant. Fifty-four patients were included in the study, with 51.9% of them presenting symptoms. Endoscopic gastritis was observed in 66.7% of patients, while histological gastritis was present in 88.9%, with statistically significant differences between the two diagnostic techniques (p = 0.004). Helicobacter spp. were identified in 44.4% (24/54) of the patients. H. pylori was detected in 42.6% of the patients by Modified Giemsa stain and in 33.3% by PCR. H. bizzozeronii was found in 35.9% of the patients, with 22.2% showing mixed infections. This study reveals a significant prevalence of Helicobacter spp. in patients from the Algarve region, with both H. pylori and zoonotic H. bizzozeronii detected. This is the first report of H. bizzozeronii DNA detection in gastric biopsies via PCR from patients undergoing UGE in Portugal, highlighting the need to consider NHPH in clinical diagnosis. It is important to include molecular methods in routine diagnostics and the need for broader studies to assess regional and national trends in Helicobacter infections besides H. pylori. Full article

Background: Helicobacter pylori infection is widely prevalent across the globe and is a major etiological agent of various gastric pathologies. This bacterium colonizes the human stomach, where it induces a range of mucosal abnormalities observable upon clinical examination. Accordingly, the present study aimed to assess the prevalence and clinical implications of H. pylori infection among patients undergoing endoscopic evaluation. Method: A cross-sectional study was conducted from January to May 2019 at endoscopy service-providing health institutions. Sociodemographic and clinical data were collected. Gastric biopsies were collected during endoscopic procedures and immediately inoculated into brain–heart infusion broth and plated out. Then, phenotypic bacterial identification was done. The collected data have been analyzed using SPSS version 23. A logistic regression model was used for association determination. Result: Among the 135 individuals enrolled in the study, 59.3% are male, and 40.7% are female, with a mean age of 45 years. H. pylori is isolated in 17.8% of participants (24/135). Notably, the majority of these isolates 71% (17/24) are from male participants, while 29% (7/24) are from females. A statistically significant association is identified between H. pylori infection and both high salt intake [AOR = 3.3; 95% CI: 1.5–10.8; p = 0.04] and the presence of duodenal ulcers [AOR = 3.8; 95% CI: 1.2–11.9; p = 0.02]. The highest prevalence of H. pylori is observed among patients diagnosed with atrophic pangastritis. Conclusions: The prevalence of H. pylori among the study participants is comparatively low. However, a significant association was observed between H. pylori infection and both high dietary salt intake and the presence of duodenal ulcers. Full article

Traditionally, Helicobacter pylori (HP) gastritis has been diagnosed by pathologists through the examination of gastric biopsies using optical microscopy with standard hematoxylin and eosin (H&E) staining. However, with the adoption of digital pathology, the identification of HP faces certain limitations, particularly due to insufficient resolution in some scanned images. Moreover, interobserver variability has been well documented in the traditional diagnostic approach, which may further complicate consistent interpretation. In this context, deep convolutional neural network (DCNN) models are showing promising results in the automated detection of this infection in whole-slide images (WSIs). The aim of the present article is to detect the presence of HP infection from our own institutional dataset of histopathological gastric biopsy samples using different pretrained and recognized DCNN and AutoML approaches. The dataset comprises 100 H&E-stained WSIs of gastric biopsies. HP infection was confirmed previously using immunohistochemical confirmation. A total of 45,795 patches were selected for model development. InceptionV3, Resnet50, and VGG16 achieved AUC (area under the curve) values of 1. However, InceptionV3 showed superior metrics such as accuracy (97%), recall (100%), F1 score (97%), and MCC (93%). BoostedNet and AutoKeras achieved accuracy, precision, recall, specificity, and F1 scores less than 85%. The InceptionV3 model was used for external validation, and the predictions across all patches yielded a global accuracy of 78%. In conclusion, DCNN models showed stronger potential for diagnosing HP in gastric biopsies compared with the auto ML approach. However, due to variability across pathology applications, no single model is universally optimal. A problem-specific approach is essential. With growing WSI adoption, DL can improve diagnostic accuracy, reduce variability, and streamline pathology workflows using automation. Full article

Helicobacter pylori is a gastric pathogen implicated in peptic ulcer disease and gastric cancer. The increasing prevalence of antibiotic-resistant strains underscores the urgent need for alternative therapeutic strategies. In this study, we investigated the chemical composition and antibacterial activity of an aqueous extract from Caulerpa lentillifera (sea grape), a farm-cultivated edible green seaweed collected from Krabi Province, Thailand. Ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) revealed that the extract was enriched in bioactive nucleosides and phenolic compounds. In vitro assays demonstrated dose-dependent inhibition of H. pylori growth following exposure to sea grape extract. Furthermore, untargeted intracellular metabolomic profiling of H. pylori cells treated with the extract uncovered significant perturbations in central carbon and nitrogen metabolism, including pathways associated with the tricarboxylic acid (TCA) cycle, one-carbon metabolism, and alanine, aspartate, and glutamate metabolism. Pyrimidine biosynthesis was selectively upregulated, indicating a potential stress-induced shift toward nucleotide salvage and DNA repair. Of particular note, succinate levels were markedly reduced despite accumulation of other TCA intermediates, suggesting disruption of electron transport-linked respiration. These findings suggest that bioactive metabolites from C. lentillifera impair essential metabolic processes in H. pylori, highlighting its potential as a natural source of antimicrobial agents targeting bacterial physiology. Full article

Helicobacter pylori, which colonizes the human gastric mucosa, uses a cluster of polar, sheathed flagella to swim across the mucous layer of the stomach. The function and biogenesis of the H. pylori flagellar sheath are poorly understood. Cardiolipin is a phospholipid that accumulates in regions of the membrane that have negative curvature, such as the cell pole, cell septum, and flagellar sheath. The final step in cardiolipin biosynthesis is catalyzed by cardiolipin synthase. H. pylori has at least two cardiolipin synthases, one of which is cardiolipin synthase C (ClsC). Bioinformatic analysis revealed that homologs of H. pylori ClsC are restricted to Helicobacter species that have sheathed flagella and the ClsC homologs are predicted lipoproteins. Fluorescence microscopy revealed that a ClsC super-folder green fluorescent protein localized to the cell pole and cell septum in H. pylori G27. Comparing the proteomes of isolated sheathed flagella from the H. pylori B128 wild type and a clsC::cat mutant, we identified five proteins that were absent in the mutant flagellum preparations. One of the proteins was FaaA, an autotransporter that localizes to the flagellar sheath. These findings suggest that the localization of FaaA and possibly other proteins to the flagellar sheath is dependent on ClsC. Full article

Background: Local audits of Helicobacter pylori (H. pylori) prescriptions and outcomes are necessary to assess guideline awareness among clinicians and treatment effectiveness. Aims: The aims were to investigate first-line prescriptions and effectiveness over a 10-year period in Ireland and evaluate the influence of the 2017 Irish consensus guidelines on these trends. Methods: Data were collected at e-CRF AEG-REDCap from the European Registry on H. pylori management (Hp-EuReg) and quality reviewed from 2013 to 2022. All treatment-naïve cases were assessed for effectiveness by modified intention-to-treat (mITT) analysis. Multivariate analysis was also performed. Results: Data from 1000 patients (mean age 50 ± 15 years; 54% female) were analyzed. Clarithromycin (C) and amoxicillin (A) triple therapy represented 88% of treatments, followed by sequential C, A, and metronidazole (M) therapy (4.3%) and triple C + M (2.7%). Bismuth quadruple therapy was prescribed in 1.7% of cases. Treatment durations of 14, 10, and 7 days accounted for 87%, 4.5%, and 8.5% of prescriptions, respectively. High-, standard-, and low-dose proton pump inhibitors (PPIs; 80 mg, 40 mg, and 20 mg omeprazole equivalent b.i.d.) were used in 86%, 0.9%, and 13% of cases, respectively. The overall eradication rate was 80%, while it was 81% for triple C + A. Good compliance and high-dose PPI were associated with higher overall mITT eradication rates (OR 4.5 and OR 1.9, respectively) and triple C + A eradication rates (OR 4.2 and OR 1.9, respectively). Overall eradication rates increased from 74% pre-2017 to 82% (p < 0.05) by the end of 2022. Similarly, the triple C + A eradication rates increased from 76% to 83% (p < 0.05). Conclusions: While first-line treatment effectiveness improved in clinical practice over time, cure rates remain below 90%. Alternative first-line strategies are required in Ireland. Full article

Helicobacter pylori (H. pylori) is one of the most prevalent chronic bacterial infections globally, significantly contributing to gastritis, peptic ulcers, and gastric malignancies. Its pathogenesis involves a complex array of virulence factors—including cagA, vacA, and urease—which facilitate mucosal colonization, immune evasion, and persistent inflammation. A major challenge in vaccine development is the bacterium’s ability to manipulate both innate and adaptive immune responses, resulting in limited natural clearance and long-term persistence. This review synthesizes H. pylori pathogenesis and host immune dynamics, highlighting their implications for vaccine design. By elucidating the molecular and cellular mechanisms underlying host–pathogen interactions, we explore how these insights inform antigen selection, adjuvant optimization, and delivery strategies. By integrating basic science with translational objectives, this review aims to support the development of an effective H. pylori vaccine, addressing global health needs, particularly in regions with a high infection burden and limited access to treatment. Full article

Background and Objectives: Chronic mucosal infection with Helicobacter pylori (H. pylori) plays a key role in the development of gastroduodenal disorders such as chronic gastritis, peptic ulcers, gastric lymphoma, and gastric cancer by triggering local immune responses and inducing hypoxic and inflammatory conditions in the gastric mucosa. This study aims to evaluate the potential diagnostic value of hypoxia-inducible factors HIF-1α and HIF-2α, along with transmembrane prolyl 4-hydroxylase (P4H-TM), as biomarkers in H. pylori-positive patients. Additionally, the study investigates the association between these markers and alterations in lipid profiles, as well as their involvement in the molecular mechanisms underlying gastric conditions like gastritis, particularly in the context of H. pylori infection. Materials and Methods: This study was conducted at Istanbul Avcılar Murat Kölük State Hospital’s General Surgery Outpatient Clinic. A total of 60 participants were included: 40 patients diagnosed with chronic gastritis (20 H. pylori-positive and 20 H. pylori-negative) and 20 healthy controls confirmed negative by 13C-urea breath test. Blood samples were collected for ELISA analysis of HIF-1α, HIF-2α, and P4H-TM levels. Additionally, lipid profiles were measured and compared among the groups. Results: No significant differences were found among the groups in terms of demographic factors such as age, sex, or body mass index (BMI). However, significant variations were observed in the levels of HIF-1α, HIF-2α, and P4H-TM across all groups (p < 0.001 for each marker). These markers were substantially elevated in the H. pylori-positive gastritis group compared to both the H. pylori-negative and healthy control groups. Receiver Operating Characteristic (ROC) curve analysis revealed that all evaluated markers exhibited strong diagnostic accuracy in differentiating H. pylori-positive individuals from other groups. HIF-1α (AUC: 0.983) and HIF-2α (AUC: 0.981) both achieved 100% sensitivity with specificities of 93.3% and 91.1%, respectively. P4H-TM showed an AUC of 0.927, with 85% sensitivity and 95.6% specificity. Conclusions: These findings indicate that HIF-1α, HIF-2α, and P4H-TM may serve as effective biomarkers for diagnosing H. pylori-positive patients and may be linked to changes in lipid metabolism. The elevated expression of these markers in response to H. pylori infection highlights their potential roles in the inflammatory and hypoxic pathways that contribute to the pathogenesis of gastric diseases such as gastritis. Full article