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Background/aims: Sessile-serrated lesions (SSLs) are challenging to detect due to their typically subtle appearance. The Workgroup serrAted polypS and Polyposis (WASP) classification was developed to diagnose SSLs endoscopically. This study aimed to evaluate the endoscopic characteristics of SSLs and the performance of the WASP classification in the Vietnamese population., Methods: This cross-sectional study was carried out on patients with lower gastrointestinal symptoms who underwent colonoscopy at a Vietnamese tertiary hospital. Univariate and multivariate analyses were performed to identify endoscopic features associated with SSLs. The performance of the WASP classification for diagnosing SSLs was assessed, and SSLs were diagnosed according to the 2019 World Health Organization (WHO) criteria., Results: There were 2489 patients, with a mean age of 52.1 ± 13.1 years and a female-to-male ratio of 1:1.1. A total of 121 specimens from 105 patients were diagnosed with SSLs. According to multivariate analysis, the endoscopic features significantly associated with SSLs were proximal location (odds ratio [OR]: 2.351; 95% confidence interval [CI]: 1.475-3.746), size >5 mm (OR: 2.447; 95% CI: 1.551-3.862), flat morphology (OR: 2.781; 95% CI: 1.533-5.044), irregular shape (OR: 4.516; 95% CI: 2.173-9.388), varicose microvascular vessels (OR: 5.030; 95% CI: 2.657-9.522), and dark spots inside the crypts (OR: 5.955; 95% CI: 3.291-10.776). The accuracy of the WASP classification for diagnosing SSLs was 94.0% (95% CI: 92.8%-95.0%)., Conclusion: Proximal location, size >5 mm, flat morphology, irregular shape, varicose microvascular vessels, and dark spots inside the crypts were significantly associated with SSLs. The WASP classification had high accuracy in the diagnosis of SSLs., (© 2024 The Author(s). JGH Open published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Background: Sessile serrated lesions (SSLs) are considered precancerous colorectal lesions that should be detected and removed to prevent colorectal cancer. Previous studies in Vietnam mainly investigated the adenoma pathway, with limited data on the serrated pathway., Aim: To evaluate the prevalence, risk factors, and BRAF mutations of SSLs in the Vietnamese population., Methods: This is a cross-sectional study conducted on patients with lower gastrointestinal symptoms who underwent colonoscopy at a tertiary hospital in Vietnam. SSLs were diagnosed on histopathology according to the 2019 World Health Organization classification. BRAF mutation analysis was performed using the Sanger DNA sequencing method. The multivariate logistic regression model was used to determine SSL-associated factors., Results: There were 2489 patients, with a mean age of 52.1 ± 13.1 and a female-to-male ratio of 1:1.1. The prevalence of SSLs was 4.2% [95% confidence interval (CI): 3.5-5.1]. In the multivariate analysis, factors significantly associated with SSLs were age ≥ 40 [odds ratio (OR): 3.303; 95%CI: 1.607-6.790], male sex (OR: 2.032; 95%CI: 1.204-3.429), diabetes mellitus (OR: 2.721; 95%CI: 1.551-4.772), and hypertension (OR: 1.650, 95%CI: 1.045-2.605). The rate of BRAF mutations in SSLs was 35.5%., Conclusion: The prevalence of SSLs was 4.2%. BRAF mutations were present in one-third of SSLs. Significant risk factors for SSLs included age ≥ 40, male sex, diabetes mellitus, and hypertension., Competing Interests: Conflict-of-interest statement: We have no financial relationships to disclose., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

It is important to explore air pollution and health effects in developing cities for early prevention rather than waiting for conditions to deteriorate as in the current megacities. This study aims to investigate the short-term health effects of air pollution in a large city in the Mekong Delta Region (MDR) of Vietnam. Air pollution data from January 2015 to December 2018 were collected from the Environmental Monitoring Centre of Can Tho City. The data of respiratory and cardiovascular disease (CVD) admissions in 18 hospitals and medical centers were collected. A time-series regression analysis was conducted using distributed lag models to examine the relationship between the air pollutants and hospitalizations including the delayed effect up to 7 days. The research findings reveal that a 10 μg increase in PM 10 was associated with an increase of 2.5% in the risk of respiratory admission for all people and 2.2% in the risk of CVD admission for the elderly on the same day. The analysis stratified by age and sex indicates that PM10 resulted in a higher risk of respiratory admission among children (0-5 years old) and males compared with other groups. PM10 and NO 2 were significantly associated with CVD admission among the elderly at lag 4 and 6 days. The effects of other air pollutants (SO 2 , O 3 ) were not observed in this study. As development continues in this region, there is an urgent need for intervention measures to minimize the health impacts associated with the expected increases in air pollution in the MDR., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: To examine whether gastric carcinoma (GC) with chromosomal instability (CIN-type GC), the largest category in the Cancer Genome Atlas classification, consists of a single genetic lineage, we conducted a multisampling analysis of genomic DNA copy-number profile., Methods: We performed array-based comparative genomic hybridization using formalin-fixed paraffin-embedded tissues from 54 gland-forming GCs containing a total of 106 DNA samples from mucosal, extramucosal invasive, and lymph node lesions. Microarray data were analyzed by unsupervised hierarchical clustering and penetrance plots. Epstein-Barr virus infection status and mismatch repair (MMR) enzyme-silencing/p53/mucin expression were examined by in situ hybridization and immunohistochemistry, respectively., Results: The samples examined were divided into gain-rich cluster A and loss-rich cluster B, which were different in tumor locus and patient age. The T1/T2-4 ratio, the frequency of small cancers (diameter ≤2-4 cm), and intestinal mucin expression were higher in cluster B than in cluster A, but there were no significant differences in the frequencies of MMR silencing, mutant p53 pattern, and lymph node metastasis between the 2 clusters., Conclusions: We demonstrated that CIN-type GC could be categorized into 2 genetic lineages which are different in terms of rapidity of local extension but similar in terms of nodal metastasis risk., (© 2019 S. Karger AG, Basel.)

We report a case of developing multiple adenocarcinoma foci in multiple hyperplastic polyps in a patient with Helicobacter pylori infection and hypergastrinemia during long-term proton pump inhibitor (PPI) therapy. A 57-year-old man, who was undergoing hemodialysis for chronic renal failure, underwent an upper gastrointestinal endoscopy to elucidate the cause of anemia. Atrophic gastritis with H. pylori infection and multiple adenocarcinoma foci in multiple hyperplastic polyps were found in the endoscopic and histological examinations. Enterochromaffin-like micronests and parietal cell protrusion in the background of the polyps suggested the existence of hypergastrinemia. The serum gastrin level was markedly high-10,206 pg/ml (normal range 37-172 pg/ml). The cause of this marked hypergastrinemia was not autoimmune gastritis and gastrinoma. After discontinuing PPI therapy and successful eradication of H. pylori, the serum gastrin level decreased to normal range. These findings indicate that hypergastrinemia may be caused by long-term PPI therapy in patients with H. pylori infection. This case suggests that hypergastrinemia may mediate gastric carcinogenesis in patients with H. pylori infection.

Introduction: The most common humoral immunodeficiency is IgA deficiency. One of the first papers addressing the cellular and molecular mechanisms underlying IgA deficiency indicated that immature IgA-positive B-lymphocytes are present in these patients. This suggests that the genetic background for IgA is still intact and that class switching can take place. At this moment, it cannot be ruled out that genetic as well as environmental factors are involved. Areas covered: A clinical presentation, the biological functions of IgA, and the management of IgA deficiency are reviewed. In some IgA deficient patients, a relationship with a loss-of-function mutation in the TACI (transmembrane activator and calcium-modulating cyclophilin ligand interaction) gene has been found. Many other genes also have been associated. Gut microbiota are an important environmental trigger for IgA synthesis. Expert commentary: Expression of IgA deficiency is due to both genetic and environmental factors and a role for gut microbiota cannot be excluded.

Background: Fever is a common cause of hospital admission in Bangladesh but causative agents, other than malaria, are not routinely investigated. Enteric fever is thought to be common., Methods: Adults and children admitted to Chittagong Medical College Hospital with a temperature of ≥38.0 °C were investigated using a blood smear for malaria, a blood culture, real-time PCR to detect Salmonella Typhi, S. Paratyphi A and other pathogens in blood and CSF and an NS1 antigen dengue ELISA., Results: We enrolled 300 febrile patients with a negative malaria smear between January and June 2012: 156 children (aged ≤15 years) and 144 adults with a median (interquartile range) age of 13 (5-31) years and median (IQR) illness duration before admission of five (2-8) days. Clinical enteric fever was diagnosed in 52 patients (17.3 %), lower respiratory tract infection in 48 (16.0 %), non-specific febrile illness in 48 (16.0 %), a CNS infection in 37 patients (12.3 %), urinary sepsis in 23 patients (7.7 %), an upper respiratory tract infection in 21 patients (7.0 %), and diarrhea or dysentery in 21 patients (7.0 %). Malaria was still suspected in seven patients despite a negative microscopy test. S. Typhi was detected in blood by culture or PCR in 34 (11.3 %) of patients. Of note Rickettsia typhi and Orientia tsutsugamushi were detected by PCR in two and one patient respectively. Twenty-nine (9 %) patients died during their hospital admission (15/160 (9.4 %) of children and 14/144 (9.7 %) adults). Two of 52 (3.8 %) patients with enteric fever, 5/48 (10.4 %) patients with lower respiratory tract infections, and 12/37 (32.4 %) patients with CNS infection died., Conclusion: Enteric fever was confirmed in 11.3 % of patients admitted to this hospital in Bangladesh with non-malaria fever. Lower respiratory tract and CNS infections were also common. CNS infections in this location merit more detailed study due to the high mortality.

Objectives: We aimed to quantify the impact of fluoroquinolone resistance on the clinical outcome of paediatric shigellosis patients treated with fluoroquinolones in southern Vietnam. Such information is important to inform therapeutic management for infections caused by this increasingly drug-resistant pathogen, responsible for high morbidity and mortality in young children globally., Methods: Clinical information and bacterial isolates were derived from a randomized controlled trial comparing gatifloxacin with ciprofloxacin for the treatment of paediatric shigellosis. Time-kill experiments were performed to evaluate the impact of MIC on the in vitro growth of Shigella and Cox regression modelling was used to compare clinical outcome between treatments and Shigella species., Results: Shigella flexneri patients treated with gatifloxacin had significantly worse outcomes than those treated with ciprofloxacin. However, the MICs of fluoroquinolones were not significantly associated with poorer outcome. The presence of S83L and A87T mutations in the gyrA gene significantly increased MICs of fluoroquinolones. Finally, elevated MICs and the presence of the qnrS gene allowed Shigella to replicate efficiently in vitro in high concentrations of ciprofloxacin., Conclusions: We found that below the CLSI breakpoint, there was no association between MIC and clinical outcome in paediatric shigellosis infections. However, S. flexneri patients had worse clinical outcomes when treated with gatifloxacin in this study regardless of MIC. Additionally, Shigella harbouring the qnrS gene are able to replicate efficiently in high concentrations of ciprofloxacin and we hypothesize that such strains possess a competitive advantage against fluoroquinolone-susceptible strains due to enhanced shedding and transmission., (© The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.)

The microbiological production of 2,3-butanediol (2,3-BDO) has attracted considerable attention as an alternative way to produce high-value chemicals from renewable sources. Among the number of 2,3-BDO-producing microorganisms, Klebsiella pneumoniae has been studied most extensively and is known to produce large quantity of 2,3-BDO from a range of substrates. On the other hand, the pathogenic characteristics of the bacteria have limited its industrial applications. In this study, two major virulence traits, outer core LPS and fimbriae, were removed through homologous recombination from 2,3-BDO-producing K. pneumoniae 2242 to expand its uses to the industrial scale. The K. pneumoniae 2242 ∆wabG mutant strain was found to have an impaired capsule, which significantly reduced its ability to bind to the mucous layer and evade the phagocytic activity of macrophage. The association with the human ileocecal epithelial cell, HCT-8, and the bladder epithelial cell, T-24, was also reduced dramatically in the K. pneumoniae 2242 ∆fimA mutant strain that was devoid of fimbriae. However, the growth rate and production yield for 2,3-BDO were unaffected. The K. pneumoniae strains developed in this study, which are devoid of the major virulence factors, have a high potential for the efficient and sustainable production of 2,3-BDO.

Solid-state nanopore has been widely studied as an effective tool to detect and analyze small biomolecules, such as DNA, RNA, and proteins, at a single molecule level. In this study, we demonstrate a rapid identification of the location of zinc finger protein (ZFP), which is bound to a specific locus along the length of a double-stranded DNA (dsDNA) to a single protein resolution using a low noise solid-state nanopore. When ZFP labeled DNAs were driven through a nanopore by an externally applied electric field, characteristic ionic current signals arising from the passage of the DNA/ZFP complex and bare DNA were detected, which enabled us to identify the locations of ZFP binding site. We examined two DNAs with ZFP binding sites at different positions and found that the location of the additional current drop derived from the DNA/ZFP complex is well-matched with a theoretical one along the length of the DNA molecule. These results suggest that the protein binding site on DNA can be mapped or that genetic information can be read at a single molecule level using solid-state nanopores.

Background: Early detection and treatment of non-invasive neoplasms can effectively reduce the incidence of advanced gastric carcinoma (GC), but only when the lineage is continuous between non-invasive and advanced tumours. Although a fraction of non-invasive neoplasms progress to invasive GC, it is difficult to identify individual progression-prone non-invasive neoplasms. To classify non-invasive gland-forming gastric neoplasms into clusters of different levels of progression risk, we applied mucin phenotyping and genomic DNA microarray analyses to intramucosal gland-forming gastric neoplasms., Methods: Formalin-fixed, paraffin-embedded tissues from 19 non-invasive and 24 invasive gland-forming neoplasms were obtained via endoscopic submucosal dissection or surgical excision. According to the Vienna classification, intramucosal neoplasms were classified as low-grade or high-grade non-invasive neoplasms (LGNs [category 3] and HGNs [category 4], respectively) or invasive carcinomas (intramucosal GCs and mucosal parts of submucosal or deeper GCs [category 5]). Neoplastic lesions were characterized by mucin phenotypes determined using monoclonal antibodies against MUC2, MUC5AC, MUC6, and CD10. Genomic DNA samples from mucosal neoplasms were subjected to array-based comparative genomic hybridization and subsequent unsupervised, hierarchical clustering with selected large-sized genes., Results: There was no significant difference in mucin phenotype between HGNs/LGNs and invasive carcinomas. The clustering classified samples into stable, unstable, and intermediate. The histological tumour grade or mucin phenotype of non-invasive neoplasms did not correlate with the clustering results. Each cluster may represent an independent lineage of different outcome because the size distribution of non-invasive tumours among the 3 clusters almost overlapped. In contrast, the unstable cluster alone included invasive carcinomas., Conclusions: These findings suggest that the outcome of individual tumours is not stochastically determined but can be predicted from the genomic copy-number profile even at the non-invasive stage. Non-invasive neoplasms of the unstable clusters, which accounted for 21% of non-invasive neoplasms, may progress to invasive carcinomas, whereas those of stable cluster may not.

Ethnopharmacological Relevance: Traditional usage suggests Citrus reticulata Blanco seeds have beneficial effects against infection. The purpose of this study was to investigate the effect of Citrus reticulata on the uroepithelium and to determine the mechanisms responsible for protection against urinary tract infection (UTI)., Materials and Methods: Human bladder cell lines T24 and 5637 were employed in a cell culture infection model to determine the effects of Citrus reticulata treatment on Escherichia coli adherence and invasion of the uroepithelium. β1 integrin and caveolin-1 mRNA expression was assessed using RT real-time PCR. β1 integrin protein expression was confirmed by Western Blot. The effect of Citrus reticulata on bacteria was investigated using antibacterial sensitivity, yeast agglutination and biofilm assays., Results: Citrus reticulata treatment decreased β1 integrin expression and reduced bacterial invasion while adhesion of uroepithelial cells was not affected. Caveolin-1 expression was not influenced either and Citrus reticulata did neither exhibit any direct antimicrobial effect nor interfered with type 1 fimbriae binding., Conclusions: Our results show that Citrus reticulata has a protective effect on the uroepithelium as seen by reduced bacterial invasion of uroepithelial cells. These properties suggest that seeds from Citrus reticulata may have therapeutic potential in preventing UTI., (© 2013 Elsevier Ireland Ltd. All rights reserved.)

This work is to explore the potential of producing biodiesel and valuable co-products from the biomass of Schizochytrium mangrovei PQ6 which was isolated from Phu Quoc Island, Kien Giang province, Vietnam. This microalga contains high lipid content (up to 70% of dry cell weight) and high level of total fatty acids, which is ideal for making biodiesel. The production of fatty acid methyl esters (FAME) from this marine microalga resulted in a yield of 88% based on algal oil and 44% based on algal biomass. The process of separating the obtained FAME into a first fraction enriched with saturated FAME (SFAME) and a second fraction enriched with unsaturated FAME (UFAME) was then investigated to exploit the valuable co-products. The obtained results shown that the mass fraction of SFAME and UFAME were 70% and 30%, respectively. The UFAME fraction contains a high content of DHA (accounting for 69.000% of TFAs). The test results of the SFAME fraction indicated that specific gravity at 15°C, flash point, water and sediment, kinematic viscosity at 40°C, sulfated ash, sulfur, copper strip corrosion at 50°C, cetane number, carbon residue, iodine number, workmanship meet Vietnam Biodiesel B100 Standard. Moreover, the utilization of waste glycerol from biodiesel process as carbon source for the cultivation of the microalgae S. mangrovei PQ6 and Spirulina platensis was also investigated., (Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

This review article presents the collected recent findings and advancements in understanding and manipulating the electronic properties of the Au/Ag NP system from the standpoint of controlling the characteristics of heterostructured core-shell NPs. The discovery of the electronic transfer effect through analysis of both Ag-Au and Au-Ag type NPs inspired the analysis of the resulting enhanced properties. First, the background on the synthesis and characterization of Ag, Au, Ag-Au, Au-Ag and Au-Ag-Au NPs, which will be used as a basis for studying the electronic transfer and stability properties is presented. Next, Mie Theory is used to inspect the optical properties of the Ag-Au NPs, revealing subtle structural characteristics in these probes, which has implications to the plasmonic properties. This is followed by the inspection of the electronic properties of the Au-Ag NPs primarily through XPS and XANES analysis, revealing the origins of the electronic transfer phenomenon. The unique electronic properties are then revealed to result in improved particle stability in terms of susceptibility to oxidation. Finally, an assessment of the resulting enhanced plasmonic sensing properties is discussed. The results are presented in terms of synthesis technique, material characterization, understanding of the electronic properties and manipulation of those properties to create Au-Ag NPs with enhanced resistance to oxidation and galvanic replacement., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Urinary tract infection (UTI) is common during pregnancy and can be associated with negative outcomes for both the mother and fetus. Increased risk of infection among these patients has been attributed to physiological changes, and less focus has been placed on Escherichia coli, the most frequent causative agent. We investigated the virulence properties of isolates causing UTI in pregnant women in Sweden, Uganda, and Vietnam, as well as nonpregnant women in Sweden. Although phylogenetic group B2 was the most prevalent group, more Ugandan isolates belonged to group B1, associated with commensal strains, than isolates from other countries. Adherence to and invasion of urothelial cells, key events in the infection process, were low among group B1 isolates from pregnant Swedish women compared to those from nonpregnant patients. Similar levels of adherence and invasion were seen in isolates from pregnant women in Uganda and Vietnam. More biofilm was formed by group B2 isolates than by those belonging to group B1 and by Ugandan group B2 isolates than by those from pregnant Swedish and Vietnamese women. The antigen 43a-encoding gene, fluA(CFT073), was most prevalent among Ugandan isolates. Expression of the biofilm components, curli and cellulose, was low among all isolates. Multidrug resistance was more common among isolates from Uganda and Vietnam than among those from Swedish patients. We suggest that while bacterial virulence properties play an important role in UTI during pregnancy, physiological changes in the host may contribute more to the incidence of infection caused by less virulent E. coli.

We recently showed that phanoside, a gypenoside isolated from the plant Gynostemma pentaphyllum, stimulates insulin secretion from rat pancreatic islets. To study the mechanisms by which phanoside stimulates insulin secretion. Isolated pancreatic islets of normal Wistar (W) rats and spontaneously diabetic Goto-Kakizaki (GK) rats were batch incubated or perifused. At both 3 x 3 and 16 x 7 mM glucose, phanoside stimulated insulin secretion several fold in both W and diabetic GK rat islets. In perifusion of W islets, phanoside (75 and 150 microM) dose dependently increased insulin secretion that returned to basal levels when phanoside was omitted. When W rat islets were incubated at 3 x 3 mM glucose with 150 muM phanoside and 0 x 25 mM diazoxide to keep K-ATP channels open, insulin secretion was similar to that in islets incubated in 150 microM phanoside alone. At 16 x 7 mM glucose, phanoside-stimulated insulin secretion was reduced in the presence of 0 x 25 mM diazoxide (P<0 x 01). In W islets depolarized by 50 mM KCl and with diazoxide, phanoside stimulated insulin release twofold at 3 x 3 mM glucose but did not further increase the release at 16 x 7 mM glucose. When using nimodipine to block L-type Ca2+ channels in B-cells, phanoside-induced insulin secretion was unaffected at 3 x 3 mM glucose but decreased at 16 x 7 mM glucose (P<0 x 01). Pretreatment of islets with pertussis toxin to inhibit exocytotic Ge-protein did not affect insulin response to 150 microM phanoside. Phanoside stimulated insulin secretion from Wand GK rat islets. This effect seems to be exerted distal to K-ATP channels and L-type Ca2+ channels, which is on the exocytotic machinery of the B-cells.

We characterized 523 Vibrio parahaemolyticus strains isolated during a survey of diarrhea patients in Khanh Hoa province, Vietnam between 1997 and 1999. Forty-nine percent of the strains were judged to belong to the pandemic strains that emerged around 1996 and spread to many countries. These strains were positive in the GS-PCR assay and carried the tdh gene. The ORF8 of the f237 phage genome, a possible marker of the pandemic clone, was absent in 10% of these strains. Eleven O: K serovars were detected among the pandemic strains and the strains representing all 11 serovars of pandemic strains were shown to be closely related regardless of the ORF8 genotype using arbitrarily primed PCR and pulsed field gel electrophoresis analyses. It was clear that a transition of major serovars occurred among the pandemic strains represented by the emergence of O3: K6 in 1997, O4: K68 in 1998, and O1: K25 in 1998 and 1999.