Metal complexes featuring a quinazoline schiff base ligand and glycine: synthesis, characterization, DFT and molecular docking analyses revealing their potent antibacterial, anti-helicobacter pylori, and Anti-COVID-19 activities.

Mixed ligand complexes of manganese(II), cobalt(II), copper(II), and cadmium(II)with an innovative Schiff base ligand denoted as (L1), 4-(2-((1E,2E)-1-(2-(p-tolyl)hydrazineylidene)propan-2-ylidene)hydrazineyl), served as the principal ligand, while glycine (L2) was employed as secondary ligand were successfully effectively characterized through a comprehensive set of analyses, including Elemental analysis, UV-Visible, FT-IR, Mass spectra, and conductometric measurements. Density functional theory (DFT) computations were executed to discern the enduring electronic arrangement, the energy gap, dipole moment and chemical hardness of the hybrid ligand assemblies. The proposed geometry for the complexes is a distorted octahedral structure. The antimicrobial efficacy of these compounds was assessed against a range of bacterial and fungal strains. Notably, these complexes exhibited promising antimicrobial activities, with the cadmium (II) complex demonstrating superior efficacy towards all tested organisms. These compounds were also examined for their antibiotic properties against H. pylori to explore their broader medical potential. The Schiff base ligand and its corresponding metal complexes displayed substantial potential as an antibiotic against H. pylori. Additionally, the antitumor potential of the synthesized complexes was assessed against MCF-7 (Breast carcinoma) cells-the Cu (II) complex demonstrated superior activity with the lowest IC50 value compared to cisplatin. Moreover, it exhibited reduced cytotoxicity towards normal cells (VERO cells) compared to cisplatin, establishing it as the most potent compound in the study. Furthermore, molecular docking was explored of the Schiff base ligand and its corresponding cadmium(II) complex. The analysis of the docking study yielded valuable structural insights that can be effectively utilized in conducting inhibition studies for example against COVID-19. This comprehensive study highlights these synthesized compounds' multifaceted applications and promising bioactive properties.

Immunobiological effects of lipopolysaccharide derived from Helicobacter pylori and influence of a proton pump inhibitor lansoprazole on human polymorphonuclear leukocytes.

Helicobacter pylori colonizes the human gastric mucosa of more than half of the human population and has a unique lipopolysaccharide (LPS) structure. LPS is the most dominant and suitable pathogen-associated molecular pattern that is detected via pattern recognition receptors. Although the priming effect of H. pylori LPS on reactive oxygen species (ROS) production of PMNs is lower than that of Escherichia coli O111:B4 LPS, LPS released from H. pylori associated with antibiotics eradication therapy may activate PMNs and increase ROS production. In addition, we describe the effects of H. pylori and E. coli O111:B4 LPSs on gene expression and the anti-inflammatory effect of lansoprazole (LPZ) in human polymorphonuclear leukocytes. LPS isolated from H. pylori and E. coli O111:B4 alters toll-like receptor 2 (TLR) and TLR4 expressions similarly. However, LPS from E. coli O111:B4 and H. pylori caused a 1.8-fold and 1.5-fold increase, respectively, in CD14 expression. All LPS subtypes upregulated TNFα and IL6 expression in a concentration-dependent manner. Although E. coli O111:B4 LPS upregulated IL8R mRNA levels, H. pylori LPS did not (≦ 100 ng/mL). Gene expression levels of ITGAM demonstrated no significant change on using both LPSs. These different effects on the gene expression in PMNs may depend on variations in LPS structural modifications related to the acquired immunomodulatory properties of H. pylori LPS. Proton pump inhibitors, i.e., LPZ, are used in combination with antibiotics for the eradication therapy of H. pylori. LPZ and its acid-activated sulphenamide form AG-2000 suppress ROS production of PMNs in a dose-dependent manner. These results suggest that LPZ combination with antibiotics for H. pylori eradication reduces gastric inflammation by suppressing ROS release from PMNs.

Gastric Carcinogenesis and Potential Role of the Transient Receptor Potential Vanilloid 1 (TRPV1) Receptor: An Observational Histopathological Study.

The potential role of the transient receptor potential Vanilloid 1 (TRPV1) non-selective cation channel in gastric carcinogenesis remains unclear. The main objective of this study was to evaluate TRPV1 expression in gastric cancer (GC) and precursor lesions compared with controls. Patient inclusion was based on a retrospective review of pathology records. Patients were subdivided into five groups: Helicobacter pylori (H. pylori)-associated gastritis with gastric intestinal metaplasia (GIM) (n = 12), chronic atrophic gastritis (CAG) with GIM (n = 13), H. pylori-associated gastritis without GIM (n = 19), GC (n = 6) and controls (n = 5). TRPV1 expression was determined with immunohistochemistry and was significantly higher in patients with H. pylori-associated gastritis compared with controls (p = 0.002). TRPV1 expression was even higher in the presence of GIM compared with patients without GIM and controls (p < 0.001). There was a complete loss of TRPV1 expression in patients with GC. TRPV1 expression seems to contribute to gastric-mucosal inflammation and precursors of GC, which significantly increases in cancer precursor lesions but is completely lost in GC. These findings suggest TRPV1 expression to be a potential marker for precancerous conditions and a target for individualized treatment. Longitudinal studies are necessary to further address the role of TRPV1 in gastric carcinogenesis.

Association of Helicobacter Pylori in Chronic Tonsillitis.

The objective of the study was to detect the presence of Helicobacter pylori in adenotonsillar tissue and to assess the association between the presence of H pylori with Chronic Tonsillitis or Adenotonsillitis. This was a cross sectional study conducted among 60 patients diagnosed with chronic tonsillitis and adeno tonsillitis undergoing tonsillectomy or adeno tonsillectomy meeting the paradise criteria in a tertiary care hospital, Pondicherry. Rapid urease test was done in the intraoperative period immediately after the specimens were taken.The rapid urease test kit was observed for color change from yellow to pink within 4 h. The tissue was sent for histopathological examination for staining with H&E and Giemsa stain to detect the presence of helicobacter pylori. The mean age of the study participants was 15.75 ± 8.46 and majority of the study participants were females. (61.7%). 66.7% and 33.3% of the study participants had chronic tonsillitis and adeno tonsillitis respectively. Oral swab showed normal flora, yeast and methicillin resistant Staphylococcus aureus in 96.6%, 1.7% and 1.7% respectively. 1.7% (1),13.3% (8) and 20% (12) of the study participants showed positive in card test immediate, at 15 min and 1 h respectively. Giemsa stain showed that 11.7% was positive for H.pylori. Out of the 7 patients with positive Giemsa stain, 4 had chronic tonsillitis and 3 had adenotonsillitis. Colonisation of adenoids and tonsils by H. pylori is a novel forefront with contradictory results dependent on the precision of the detective techniques used and population studied. Further research may be warranted to establish the varied colonisation depending on the geographical locations.

Potassium-competitive Acid Blockers: Current Clinical Use and Future Developments.

PURPOSE OF THE REVIEW: Acid suppression with proton pump inhibitors (PPIs) represents the standard of care in the treatment of acid-related diseases. However, despite their effectiveness, PPIs display some intrinsic limitations, which underlie the unmet clinical needs that have been identified over the past decades. The aims of this review are to summarize the current status and future development of the new class of antisecretory drugs (potassium-competitive acid blockers, P-CABs) that have recently been introduced into medical practice. RECENT FINDINGS: Over the past decades, clinical needs unmet by the current acid suppressants have been recognized, especially in the management of patients with GERD, Helicobacter pylori infection and NSAID-related peptic ulcer. The failure to address these needs is mainly due to their inability to achieve a consistent acid suppression in all patients and, particularly, to control nighttime acidity. It was then realized that an extended duration of acid suppression would exert additional benefits. The available data with P-CABs show that they are able to address these unmet clinical needs. Four different P-CABs (vonoprazan, tegoprazan, fexuprazan and keverprazan) are currently available. However, only two of them are approved outside Asia. Vonoprazan is available in North, Central and South America while tegoprazan is marketed only in Latin American countries. Two other compounds (namely linazapran glurate and zestaprazan) are presently under clinical development. While clinical trials on GERD have been performed with all P-CABs, only vonoprazan and tegoprazan have been investigated as components of Helicobacter pylori eradication regimens. The available data show that-in the above two clinical indications-P-CABs provide similar or better efficacy in comparison with PPIs. Their safety in the short-term overlaps that of PPIs, but data from long-term treatment are needed.

Gene content, phage cycle regulation model and prophage inactivation disclosed by prophage genomics in the Helicobacter pylori Genome Project.

Prophages can have major clinical implications through their ability to change pathogenic bacterial traits. There is limited understanding of the prophage role in ecological, evolutionary, adaptive processes and pathogenicity of Helicobacter pylori, a widespread bacterium causally associated with gastric cancer. Inferring the exact prophage genomic location and completeness requires complete genomes. The international Helicobacter pylori Genome Project (HpGP) dataset comprises 1011 H. pylori complete clinical genomes enriched with epigenetic data. We thoroughly evaluated the H. pylori prophage genomic content in the HpGP dataset. We investigated population evolutionary dynamics through phylogenetic and pangenome analyses. Additionally, we identified genome rearrangements and assessed the impact of prophage presence on bacterial gene disruption and methylome. We found that 29.5% (298) of the HpGP genomes contain prophages, of which only 32.2% (96) were complete, minimizing the burden of prophage carriage. The prevalence of H. pylori prophage sequences was variable by geography and ancestry, but not by disease status of the human host. Prophage insertion occasionally results in gene disruption that can change the global bacterial epigenome. Gene function prediction allowed the development of the first model for lysogenic-lytic cycle regulation in H. pylori. We have disclosed new prophage inactivation mechanisms that appear to occur by genome rearrangement, merger with other mobile elements, and pseudogene accumulation. Our analysis provides a comprehensive framework for H. pylori prophage biological and genomics, offering insights into lysogeny regulation and bacterial adaptation to prophages.

Anti-Helicobacter pylori Infection Treatment and Pulmonary Hypersensitivity: Case Series and Review of the Literature.

BACKGROUND: Helicobacter pylori (H. pylori) infection is currently widespread throughout the world. Bismuth-containing quadruple therapy is widely used, but it has rarely been associated with interstitial lung disease. CASE PRESENTATION: We described six cases with similar clinical symptoms and typical pulmonary interstitial imaging changes during anti-H. pylori therapy, usually on Days 7-12 following treatment. Anti-H. pylori infection treatment was discontinued when it was suspected to be the cause of the clinical symptoms, and all of the patients accepted observation therapy. All of them had a favorable outcome, the clinical symptoms returned to normal almost 1 week later, and the chest computed tomography (CT) scan images showed remarkable absorption 4 weeks later. CONCLUSIONS: Drug interactions could be the cause, and the most likely drug was furazolidone. All of the patients recovered quickly after drug discontinuation, and low-dose steroid may help shorten the recovery time.

Cost-effective endoscopic screening for gastric cancer in a cohort with low Helicobacter pylori prevalence.

BACKGROUND AND AIM: Periodic endoscopic screening for gastric cancer (GC) is widely performed in East Asia; however, the optimal screening strategy remains unclear. This study aimed to determine the most cost-effective endoscopic screening strategy for the detection and treatment of GC in a cohort with a low Helicobacter pylori prevalence. METHODS: The following data were retrospectively extracted from participants who received screening endoscopy between April 2019 and March 2023: age, H. pylori infection status, presence of intestinal metaplasia, pathological diagnosis of GC, and the interval between the most recent endoscopies. A Markov state transition model was constructed based on the cohort data. The cost-effectiveness of 15 strategies with different starting ages (40/50/60 years) and screening intervals (1/2/3/4/5 years) was compared. The net monetary benefit (NMB) and incremental cost-effectiveness ratio (ICER) of quality-adjusted life-years gained by treatment were used as outcomes. RESULTS: A simulation model was constructed based on the cohort data of 94 137 participants (mean age 54.5 years, males 57.9%; 74.4% H. pylori-naïve, 94.2% intestinal metaplasia-negative). The results of the base-case analysis showed that the screening strategy of 4-year intervals starting at the age of 40 years had the highest NMB (97 401 578 yen). In both the Monte Carlo simulation and one-way sensitivity analysis with a varying probability of H. pylori infection status transition, the ICER was superior in the screening strategy every 4 years, starting at age 40 years. CONCLUSIONS: Our simulation showed that endoscopic screening at 4-year intervals starting at the age of 40 years was the most cost-effective method.

Association of triglyceride-glucose index with helicobacter pylori infection and mortality among the US population.

BACKGROUND: Limited research has explored the potential association between the Triglyceride-Glucose (TyG) and mortality, especially in individuals with Helicobacter pylori (H. pylori) infection. This study seeks to investigate the correlation between the TyG index and H. pylori infection and investigate whether the associations between the TyG index exposure and all-cause mortality are mediated by H. pylori infection. METHODS: The study utilized data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018, incorporating a final sample size of 2,187 participants. Both univariable and multivariable-adjusted logistic regression analyses were employed to examine the relationship between H. pylori infection and relevant covariates. To assess the association between TyG index, and all-cause mortality in individuals with or without H. pylori infection, Cox regression analysis, and restricted regression cubic spline analysis were implemented. RESULTS: A significant positive correlation was observed between the TyG index and an elevated risk of H. pylori infection [OR 1.157, 95% CI (1.383 ~ 1.664)]. This correlation persisted even after adjusting for confounding factors [OR 1.189, 95% CI (1.003, 1.411), P < 0.05]. Furthermore, in patients with positive H. pylori infection, a noteworthy nonlinear correlation between the TyG index and all-cause mortality was identified (P = 0.0361). With an increase in the TyG index, all-cause mortality exhibited a corresponding rise, particularly following adjustment for all potential confounding factors. Conversely, in patients with negative H. pylori infection, no significant association was observed between the TyG index and all-cause mortality after adjusting for potential confounding factors. CONCLUSION: A higher TyG index was linked to increased H. pylori infection risks. Participants in the higher quantile group of the TyG index are positively associated with higher all-cause mortality compared to the higher quantile group of the TyG index in H. pylori-positive participants instead of H. pylori-negative participants.

[Duodenitis Russell bodies. Review of the entity and associations beyond H. pylori]. / Duodenitis con cuerpos de Russell. Revisión de la entidad y posibles asociaciones más allá del H. pylori.

Plasma cells known as "Mott cells" present non-secretable accumulations of immunoglobulins called "Russell bodies". Its presence is related to hematological neoplasms, but it can appear in chronic inflammatory processes. The most common occurrence within the digestive tract is the gastric antrum associated with H. pylori infection. Our patient is added the rare extragastric cases where the association with H. pylori is inconsistent. We have found a frequent appearance of lower digestive and urological neoplasms in relation to these cases, justified by the expression of circulating cytokines in the tumor area that lead to the overactivation of plasma cells. This possible association could lead us to know data about the tumor environment and serve us for early diagnosis or future therapeutic targets.

Helicobacter Pylori infection in children with inflammatory bowel disease: a prospective multicenter study.

BACKGROUND: The relationship between Helicobacter-pylori(Hp)infection and inflammatory-bowel-disease(IBD) in pediatric-patients remains controversial. We aimed to assess the Hp-infection occurrence in newly-diagnosed pediatric-patients with IBD compared to no-IBD patients. Additionally, we aimed to examine differences in clinical-activity-index(CAI) and endoscopic-severity-score(ESS)between IBD-patients with and without Hp-infection, at baseline and at 1-year-follow-up(FU), after eradication-therapy(ET). METHODS: IBD diagnosis was based on Porto-criteria, and all patients underwent gastroscopy at baseline and 1-year FU. For Crohn's-disease(CD) and ulcerative colitis(UC), IBD-CAI and -ESS were classified using PCDAI/SES-CD and PUCAI/UCEIS, respectively. RESULTS: 76 IBD-patients were included in the study[35 F(46.1%),median-age 12(range 2-17)]. CD and UC were diagnosed in 29(38.2%) and 45(59.2%)patients, respectively, and unclassified-IBD in two(2.6%)patients. Non-IBD patients were 148[71 F(48.0%),median-age 12(range 1-17)]. Hp-infection at baseline was reported in 7(9.2%) and 18(12.2%)IBD and non-IBD patients, respectively(p = 0.5065). The 7 IBD patients with Hp infection were compared to 69 IBD patients without Hp-infection at baseline evaluation, and no significant differences were reported considering CAI and ESS in these two groups. At 1-year FU, after ET, IBD patients with Hp infection improved, both for CAI and ESS, but statistical significance was not reached. CONCLUSION: The occurrence of Hp-infection did not differ between IBD and no-IBD patients. No differences in CAI or ESS were observed at the diagnosis, and after ET no worsening of CAI or ESS was noted at one-year FU, between Hp-positive and -negative IBD patients.

Oral Hygiene With Neutral Electrolyzed Water and Systemic Therapy Increases Gastric Helicobacter pylori Eradication and Reduces Recurrence.

OBJECTIVES: Helicobacter pylori gastric infection strongly correlates with gastric diseases such as chronic gastritis, functional dyspepsia, and complications such as peptic ulcers and gastric cancer. In developing countries, systemic therapies are not usually successful due to elevated antibiotic resistance. Additionally, oral H. pylori infection and periodontal disease correlate with gastric treatment failures. This study aimed to explore the effect of an integral therapy, comprising oral hygiene and concomitant systemic treatment, to increase the eradication of gastric infection and recurrences. MATERIALS AND METHODS: A prospective, randomized, four-arm, parallel-group, open-label clinical trial was conducted to investigate the efficacy of integral therapy to eradicate gastric H. pylori infection and avoid recurrences in double-positive (real-time PCR oral and gastric infection) patients. Oral hygiene involved mouthwash with neutral electrolyzed water (NEW), with or without periodontal treatment. One hundred patients were equally distributed into four groups: NS, NS-PT, NEW, and NEW-PT. All patients had concomitant systemic therapy and additionally, the following oral treatments: mouthwash with normal saline (NS), periodontal treatment and mouthwash with normal saline (NS-PT), mouthwash with NEW (NEW), and periodontal treatment and mouthwash with NEW (NEW-PT). Gastric and oral infection and symptoms were evaluated one and four months after treatments. RESULTS: Integral therapy with NEW-PT increased gastric eradication rates compared with NS or NS-PT (84%-96% vs. 20%-56%; p < 0.001). Even more, a protective effect of 81.2% (RR = 0.1877; 95% CI: 0.0658-0.5355; p = 0.0018) against recurrences and 76.6% (RR = 0.2439; 95% CI: 0.1380-0.4310; p < 0.001) against treatment failure (eradication of infection and associated symptoms) was observed in patients from the NEW and NEW-PT groups. CONCLUSIONS: Implementation of oral hygiene and systemic treatment can increase the eradication of gastric infection, associated symptoms, and recurrences. NEW is recommended as an antiseptic mouthwash due to its efficacy and short- and long-term safety.

Primary Gastric and Duodenal Mucosa-Associated Lymphoid Tissue Lymphoma With Symptomatic Anemia.

Mucosal-associated lymphoid tissue (MALT) is a low-grade lymphoma derived from marginal zone B cells in extranodal tissue. Gastric MALT lymphoma is frequently seen; however, duodenal MALT lymphoma is rare, and there is no standardized knowledge up to date about the management of the disease. We present a case of a 56-year-old woman with gastric and duodenal MALT lymphoma.

Profile of gastroduodenal perforation patients admitted in a rural tertiary care hospital: An observational cross-sectional study.

Background: Gastro-duodenal perforation is a common surgical emergency that remains a formidable health burden worldwide with significant morbidity and mortality. Ulcer disease remains the most common cause of gastro-duodenal perforation. Diagnosing the presence of H. pylori can help eradicate the infection from the community at large and thereby reduce the chances of gastro-duodenal perforation. Aims: To assess the clinical presentation of gastro-duodenal perforation patients and to evaluate the detection of Helicobacter pylori infection by available investigations. Materials and Methods: A descriptive observational study was conducted among 80 patients presenting with clinical features suggestive of gastro-duodenal perforation and confirmed by clinical, radiological basis and operative findings admitted at a rural tertiary care hospital during 2019-2020. Detailed history was taken from the patient/party, clinically examined, and blood/tissue samples were investigated. The patients were managed with standard treatment modality in the studied institute. Data were collected, compiled, and entered MS Excel and analyzed using appropriate software. Descriptive analysis was done in the form of proportion for categorical variables, mean or median for continuous variables. Result: Cases of gastro-duodenal perforations were more among middle to later age of life, mostly affecting married male patients hailed from rural area and unskilled workers. History of intake of spicy food, prolonged starvation, history of NSAID use were common among them. Majority of the patients had history of pain abdomen in the past suggesting of PUD and history of taking variety group of acid reducing agents. Most of them presented with epigastric pain, vomiting, abdominal distension along with other signs of peritonitis. Obliteration of liver dullness and free gas under right dome of diaphragm was also noted in large proportion among them. Majority of cases were found positive for H. pylori on Histology (85%), followed by rapid urease test (RUT) (80%) and a positivity of 72.5% and 68.8% on serum IgG and IgA antibody respectively. Rapid Urease Test was more sensitive as well as specific in diagnosing of H. pylori than antibody detection test. Conclusion: Early detection of H. pylori infection and treatment with potent anti H. pylori therapy postoperatively has been found to be adequate.

Implications of silver nanoparticles for H. pylori infection: modulation of CagA function and signaling.

Background: Helicobacter pylori infection poses a significant health burden worldwide, and its virulence factor CagA plays a pivotal role in its pathogenesis. Methods: In this study, the interaction between H. pylori-infected AGS cells and silver nanoparticles (AgNPs) was investigated, with a focus on the modulation of CagA-mediated responses, investigated by western blotting. Both, the dose-dependent efficacy against H. pylori (growth curves, CFU assay) and the impact of the nanoparticles on AGS cells (MTT assay) were elucidated. Results: AGS cells infected with H. pylori displayed dramatic morphological changes, characterized by elongation and a migratory phenotype, attributed to CagA activity. Preincubation of H. pylori with AgNPs affected these morphological changes in a concentration-dependent manner, suggesting a correlation between AgNPs concentration and CagA function. Conclusion: Our study highlights the nuanced interplay between host-pathogen interactions and the therapeutic potential of AgNPs in combating H. pylori infection and offers valuable insights into the multifaceted dynamics of CagA mediated responses.

Boosting the Anti-Helicobacter Efficacy of Azithromycin through Natural Compounds: Insights From In Vitro, In Vivo, Histopathological, and Molecular Docking Investigations.

BACKGROUND: Antimicrobial-resistant Helicobacter pylori (H. pylori) poses a significant public health concern, especially given the limited therapeutic options for azithromycin-resistant strains. Hence, there is a necessity for new studies to reconsider the use of azithromycin, which has diminished in effectiveness against numerous strains. Thus, we aimed to augment azithromycin's anti-Helicobacter properties by combining it with curcumin in different formulations, including curcumin in clove oil, curcumin nano-gold emulsion, and curcumin nanoemulsion. METHODS: The antimicrobial activities of the investigated compounds, both individually and in combination with other anti-Helicobacter drugs, were evaluated. Their antibiofilm and anti-virulence properties were assessed using both phenotypic and genotypic methods, alongside molecular docking studies. Our findings were further validated through mouse protection assays and histopathological analysis. RESULTS: We observed high anti-Helicobacter activities of curcumin, especially curcumin nanoemulsion. A synergistic effect was detected between curcumin nanoemulsion and azithromycin with fraction inhibitory concentration index (FICI) values <0.5. The curcumin nanoemulsion was the most active anti-biofilm and anti-virulence compound among the examined substances. The biofilm-correlated virulence genes (babA and hopQ) and ureA genes were downregulated (fold change <1) post-treatment with curcumin nanoemulsion. On the protein level, the anti-virulence activities of curcumin nanoemulsion were documented based on molecular docking studies. These findings aligned with histopathological scoring of challenge mice, affirming the superior efficacy of curcumin nanoemulsion/azithromycin combination. CONCLUSION: The anti-Helicobacter activities of all curcumin physical forms pose significant challenges due to their higher  minimum inhibitory concentration (MIC) values exceeding the maximum permissible level. However, using curcumin nanoemulsion at sub-MIC levels could enhance the anti-Helicobacter activity of azithromycin and exhibit anti-virulence properties, thereby improving patient outcomes and addressing resistant pathogens. Therefore, more extensive studies are necessary to assess the safety of incorporating curcumin nanoemulsion into H. pylori treatment.

Structural insights into the assembly pathway of the Helicobacter pylori CagT4SS outer membrane core complex.

Cag type IV secretion system (CagT4SS) translocates oncoprotein cytotoxin-associated gene A (CagA) into host cells and plays a key role in the pathogenesis of Helicobacter pylori. The structure of the outer membrane core complex (OMCC) in CagT4SS consists of CagX, CagY, CagM, CagT, and Cag3 in a stoichiometric ratio of 1:1:2:2:5 with 14-fold symmetry. However, the assembly pathway of OMCC remains elusive. Here, we report the crystal structures of CagT and Cag3-CagT complex, and the structural dynamics of Cag3 and CagT using hydrogen deuterium exchange-mass spectrometry (HDX-MS). The interwoven interaction of Cag3 and CagT involves conformational changes of CagT and ß strand swapping. In conjunction with biochemical and biophysical assays, we further demonstrate the different oligomerization states of Cag3 and Cag3-CagT complex. Additionally, the association with CagM requires the pre-formation of Cag3-CagT complex. These results demonstrate the generation of different intermediate sub-assemblies and their structural flexibility, potentially representing different building blocks for OMCC assembly.

Implications of lncRNAs in Helicobacter pylori-associated gastrointestinal cancers: underlying mechanisms and future perspectives.

Helicobacter pylori (H. pylori) is a harmful bacterium that is difficult to conveniently diagnose and effectively eradicate. Chronic H. pylori infection increases the risk of gastrointestinal diseases, even cancers. Despite the known findings, more underlying mechanisms are to be deeply explored to facilitate the development of novel prevention and treatment strategies of H. pylori infection. Long noncoding RNAs (lncRNAs) are RNAs with more than 200 nucleotides. They may be implicated in cell proliferation, inflammation and many other signaling pathways of gastrointestinal cancer progression. The dynamic expression of lncRNAs indicates their potential to be diagnostic or prognostic biomarkers. In this paper, we comprehensively summarize the processes of H. pylori infection and the treatment methods, review the known findings of lncRNA classification and functional mechanisms, elucidate the roles of lncRNAs in H. pylori-related gastrointestinal cancer, and discuss the clinical perspectives of lncRNAs.

Helicobacter pylori infection delays neutrophil apoptosis and exacerbates inflammatory response.

Aim: Understanding molecular mechanisms of Helicobacter pylori (H. pylori)-induced inflammation is important for developing new therapeutic strategies for gastrointestinal diseases.Materials & methods: We designed an H. pylori-neutrophil infection model and explored the effects of H. pylori infection on neutrophils.Results: H. pylori infected neutrophils showed a low level of apoptosis. H. pylori stimulation activated the NACHT/LRR/PYD domain-containing protein 3 (NLRP3)-gasdermin-D (GSDMD) pathway for interleukin (IL)-1ß secretion. However, IL-1ß secretion was not completely dependent on GSDMD, as inhibition of autophagy significantly reduced IL-1ß release, and autophagy-related molecules were significantly upregulated in H. pylori-infected neutrophils.Conclusion: Therefore, H. pylori infection inhibits neutrophils apoptosis and induces IL-1ß secretion through autophagy. These findings may be utilized to formulate therapeutic strategies against H. pylori mediated chronic gastritis.

[Box: see text].

Mycobacterium bovis BCG reverses deleterious effects of H. pylori components towards gastric barrier cells in vitro.

Mycobacterium bovis (M. bovis) Bacillus Calmette-Guerin (BCG) strain used in immunotherapy of bladder cancer (onco-BCG) due to its acid tolerance can be a candidate for prevention or reversion of deleterious effects towards gastric cell barrier initiated by gastric pathogen Helicobacter pylori (Hp) with high resistance to commonly used antibiotics. Colonization of gastric mucosa by Hp promotes oxidative stress, apoptosis resulting in the gastric barrier damage. The aim of this study was to examine the ability of onco-BCG bacilli to control the Hp driven gastric damage using the model of Cavia porcellus primary gastric epithelial cells or fibroblasts in vitro. These cells were treated with Hp surface antigens (glycine acid extract-GE or lipopolysaccharide-LPS) alone or with onco-BCG bacilli and evaluated for cell apoptosis and proliferation in conjunction with the level of soluble lipid peroxidation marker (s4HNE). The cell migration was determined by "wound healing assay", while cytokine response of cells, including interleukin (IL)-33, IL-1ß, IL-8 and tumor necrosis factor alpha (TNF-α), by the ELISA. The apoptosis of cells pulsed in vitro with Hp surface components present in GE or with LPS was reduced after exposure of cells to mycobacteria. Similarly, the cell regeneration which was diminished by Hp LPS has been improved in response to mycobacteria. This study reveals that vaccine mycobacteria may reduce gastric barrier damage induced by Hp infection.