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In emergency cases such as disasters, supplying enough safe drinking water is one of the most urgent needs for human life. This research aimed to develop a chemical- and electricity-free drinking water treatment system based on microfiltration and catalysts of Ag and Ag-TiO 2 -SiO 2 coated on glass spheres in both dark and sunlight conditions. The system was applied to treat raw water samples taken from five rivers in Vietnam, simulated floodwater samples with high turbidity and E. coli concentration, and real flooding water samples. The results showed the filtration unit fed with simulated floodwater generated lower fluxes and shorter working durations before chemical cleaning than that fed with normal river water. However, filtrate quality was not significantly different for these five water samples with very low values of turbidity (0-0.66 NTU), total coliform (5-19 CFU (100 mL) -1 ), and E. coli (0-17 CFU (100 mL) -1 ). The catalyst units using glass spheres coated with either Ag in dark and sunlight or Ag-TiO 2 -SiO 2 under sunlight can completely remove E. coli and coliform as well as additionally mitigate natural organic matters. This study hence suggests the combination of microfiltration and Ag-based catalytic treatment for safe drinking water supply in emergencies, especially for flooding conditions.

Introduction: Multidrug-resistant (MDR) Gram-negative bacilli including carbapenem-resistant Gram-negative Enterobacteriaceae (CRE) threaten global health. Little is known, however, about the distribution of antimicrobial resistance genes in MDR isolated from patients in Vietnamese hospitals. In this study, we collected MDR Escherichia coli , defined as E. coli resistance against all fluoroquinolones, aminoglycosides, and carbapenems., Aim: This study was designed to clarify the molecular epidemiology of Escherichia coli isolates resistant to carbapenems, fluoroquinolones, and aminoglycosides isolated from patients admitted to one of the largest hospitals in Vietnam in 2014-2019 based on both whole-genome sequencing (WGS) and phenotypic data. Methodology . Sixty-seven Vietnamese isolates screened by drug resistance by the disk test were subjected to WGS, and their sequences were analyzed to determine their multilocus sequence type (MLST), O-types, H-types, distribution of drug resistance genes, plasmid types, pathogenicity islands (PIs), virulence factor distribution, and phylogenetic evolution using the WGS data., Results: Among the STs detected, ST410 was relatively dominant. Dominant O-types and H-types were O102 and H9 and showed some links, such as those between O102 and H8. The most dominant plasmid type and carbapenemase type were 4 and NDM-5, respectively. MLST, O-types, H-types, plasmid types, and types of carbapenemases were very heterogeneous among the isolates, with no clear correlation between them. Dominant plasmid type carrying drug resistance gene was IncQ1_1. The percentage of isolates positive for drug resistance genes, such as anti-beta-lactams and aminoglycosides, was relatively high because the isolates screened were resistant to carbapenems, fluoroquinolones, and aminoglycosides., Conclusions: MDR E. coli isolates isolated at a high-volume Vietnamese hospital were very heterogeneous, suggesting that they were acquired from different sources, including nosocomial infection, animals, and water. Eradication of MDR E. coli from hospitals and other clinical environments is very challenging because a single measure may be ineffective., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2024 Tohru Miyoshi-Akiyama et al.)

Cuprous oxide/copper/cupric oxide nanoparticles were synthesized through a hybrid process involving anodic dissolution and a controlled redox reaction between NaOH and glucose in the solution. The study demonstrates the structural manipulation of the material by varying the reaction components within the solution. Morphology, structural analyses using SEM (Scanning Electron Microscope), EDX (Energy-dispersive X-ray spectroscopy), TEM (Transmission Electron Microscope), FTIR (Fourier Transform Infrared Spectroscopy), XRD (X-ray diffraction), and XPS (X-ray photoelectron spectroscopy) unveiled the tunability of the material's structure based on the reaction components. Nitrogen adsorption analysis employing the Brunauer-Emmett-Teller (BET) equation confirmed the material's porosity, while Dynamic Light Scattering (DLS) measurements provided insights into the materials' hydrodynamic size and zeta potential. The results demonstrated that by increasing the glucose/NaOH ratio during the reaction, the different structures and morphologies of the distinct products were obtained from the clustering of small nanoparticles to cubic shape and flower-like structure. Antibacterial activity tests conducted on various bacterial strains showed a correlation between the morphology and structure of the material and its antibacterial properties. The highest substantial antibacterial efficacy against all tested bacterial strains at a dosage of 100 μg/L was obtained for the samples with clustering morphology, whereas the remaining materials showed no discernible antibacterial effect against one of the studied bacteria. The results also demonstrated that the sample with a clustering structure exhibited superior antibacterial properties when dispersed in water containing dimethylsulfoxide., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Background: Adjunctive glucocorticoids are widely used to treat human immunodeficiency virus (HIV)-associated tuberculous meningitis despite limited data supporting their safety and efficacy., Methods: We conducted a double-blind, randomized, placebo-controlled trial involving HIV-positive adults (≥18 years of age) with tuberculous meningitis in Vietnam and Indonesia. Participants were randomly assigned to receive a 6-to-8-week tapering course of either dexamethasone or placebo in addition to 12 months of antituberculosis chemotherapy. The primary end point was death from any cause during the 12 months after randomization., Results: A total of 520 adults were randomly assigned to receive either dexamethasone (263 participants) or placebo (257 participants). The median age was 36 years; 255 of 520 participants (49.0%) had never received antiretroviral therapy, and 251 of 484 participants (51.9%) with available data had a baseline CD4 count of 50 cells per cubic millimeter or less. Six participants withdrew from the trial, and five were lost to follow-up. During the 12 months of follow-up, death occurred in 116 of 263 participants (44.1%) in the dexamethasone group and in 126 of 257 participants (49.0%) in the placebo group (hazard ratio, 0.85; 95% confidence interval, 0.66 to 1.10; P = 0.22). Prespecified analyses did not reveal a subgroup that clearly benefited from dexamethasone. The incidence of secondary end-point events, including cases of immune reconstitution inflammatory syndrome during the first 6 months, was similar in the two trial groups. The numbers of participants with at least one serious adverse event were similar in the dexamethasone group (192 of 263 participants [73.0%]) and the placebo group (194 of 257 participants [75.5%]) (P = 0.52)., Conclusions: Among HIV-positive adults with tuberculous meningitis, adjunctive dexamethasone, as compared with placebo, did not confer a benefit with respect to survival or any secondary end point. (Funded by the Wellcome Trust; ACT HIV ClinicalTrials.gov number, NCT03092817.)., (Copyright © 2023 Massachusetts Medical Society.)

Diagnosis of extrapulmonary tuberculosis remains challenging in lower-middle income countries with high burden of tuberculosis (TB). This study aims to describe the histological characteristics in biopsy samples from patients with confirmed TB. This is a retrospective study of clinical biopsy specimens with positive liquid medium culture for Mycobacterium tuberculosis and histopathological examination in the National Lung Hospital in Vietnam. Among 1045 biopsy specimens with mycobacteria culture, the overall rate of growth of Mycobacteria tuberculosis in culture was 20.7% (216/1045). The positivity rates of MIGT culture among surgical biopsy specimens were 75% in bone specimen, followed by vertebral specimens (51.3%), and joint specimens (26.4%). For specimens obtained by the fine needle aspiration, the positivity rates of MIGT culture were 26.3% in lymph node and 25.3% in pleural specimen. Among specimens with culture confirmation of TB, the most common histopathoglogical suggestive finding of TB was the presence of epithelioid cell (83.3%), Langhans giant cells (75.9%), and caseous necrosis (75.5%). The high proportion of histological features suggestive of TB among the TB culture confirmed biopsy samples support for further evaluation of histological examination and its combination with other recommended rapid molecular assays in specimens with suspicion of TB., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

In this work, we developed a facile one-step pyrolysis method for preparing porous ZnO/biochar nanocomposites (ZBCs) with a large surface area to enhance the removal efficiency of dye from aqueous solution. Peanut shells were pyrolyzed under oxygen-limited conditions with a molten salt ZnCl 2 , which played the roles of the activating agent and precursor for the formation of nanoparticles. The effects of the mass ratio between the molten salt ZnCl 2 and peanut shells as well as pyrolysis temperature on the formation of ZBCs were investigated. Characterization results revealed that the as-synthesized ZBCs exhibited a highly porous structure with a specific surface area of 832.12 m 2 /g, suggesting a good adsorbent for efficient removal of methylene blue (MB). The maximum adsorption capacity of ZBCs on MB was 826.44 mg/g, which surpassed recently reported adsorbents. The formation mechanism of ZnO nanoparticles on the biochar surface was due to ZnCl 2 vaporization and reaction with water molecules extracted from the lignocellulosic structures. This study provides a basis for developing a simple and large-scale synthesis method for wastewater with a high adsorption capacity., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

In this work, a green, novel, fast, and facile approach for synthesizing a SiO 2 /C nanocomposite series from rice husk (RH) through quenching and grinding techniques has been reported along with its application for the adsorptive removal of Reactive Red 120 (RR120) dye from an aqueous solution. The effect of carbonization temperature on the textural and interfacial features of RH was confirmed by scanning electron microscopy (SEM), while the structure and elemental composition of the as-synthesized RH were investigated via XRD, Brunauer-Emmett-Teller (BET), FT-IR, Raman, and X-ray photoelectron spectroscopy (XPS). The RH had a high surface area (521.35 m 2 g -1 ), large micropores, mesopores, and total pore volumes of 0.5059, 3.9931, and 5.2196 cm 3 g -1 , while SiO 2 and C were the two major components. In the batch adsorption test, the effects of pH, contact time, adsorbent mass, temperature, and initial RR120 concentration were investigated. The maximum adsorption capacity was fitted by Langmuir, Freundlich, Temkin, Dubinin-Radushkevich (D-R), Hasley, Harkins-Jura, and BET isotherm models, and Langmuir was the best-fitted model. In addition, the pseudo-first-order, pseudo-second-order, intraparticle diffusion, and Elovich chemisorption models were used to explain the adsorption kinetics. Additionally, the values of Gibbs free energy, enthalpy, and entropy thermodynamics suggested that the RR120 adsorption phenomenon by RH8-3 was endothermic and spontaneous. The adsorption process was controlled by a physical mechanism, and the maximum adsorption capacity was found to be 151.52 mg g -1 at pH 2, with a contact time of 90 min, adsorbent amount of 0.03 g, and temperature of 313 K. The adopted technique may open up a new alternative route for the mass utilization of RH for the removal of dyes in water and wastewater and also for various practical applications., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

This study conducted a field investigation in the behavior of visitors in the pagoda and burning incense as well as its air pollution situation in Vietnam, and revealed that 92% of people used stick form for offering incense and mainly burning either 1 or 3 sticks/time. Incense smoke exposure caused aroma, comfortable, eye irritation, or hard to breathe. There were 70% of people being aware of the hazard of incense smoke. VOCs, PM 2.5 , PM 10 , and CO 2 concentrations from burning incense in the Great hall were 1.6-2.5 times higher than those in outside areas. Pollutants' concentrations on the first of the month, full moon day, and Lunar New Year were from 1.5 to 2.0 times higher than those of normal days. A model was designed to collect incense smoke emitted by burning 1 and 3 sticks of seven types of incense on an open area. Except for CO found at low concentrations, VOCs, HCHO, PM 2.5 , PM 10 , and CO 2 appeared in the smoke with the maximum concentrations higher 2.5-13.5 times than their allowable values. A photocatalytic device using titania nanotubes (TNTs) impregnated with various metals (Cd, Zn, Al, Cu, and Fe) was installed for incense smoke treatment. Effect of type and amount of photocatalyst, as well as initial VOC concentration, were tested. The results show that using 2.0 g of Zn/TNT photocatalysts under UV irradiation provided the highest VOC removal efficiency of 73%, suggesting the potential of application for burning incense in open areas., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this study, two types of agricultural wastes, sugarcane bagasse (SB) and cassava root husks (CRHs), were used to fabricate biochars. The pristine biochars derived from SB and CRHs (SBB and CRHB, respectively) were modified using ZnO nanoparticles to generate modified biochars (SBB-ZnO and CRHB-ZnO, respectively) for the removal of Reactive Red 24 (RR24) from stimulated wastewater. Batch experiments were performed to evaluate the effects of ZnO nanoparticles' loading ratio, solution pH, contact time, and initial RR24 concentration on the RR24 adsorption capacity of biochars. The RR24 adsorption isotherm and kinetic data on SBB, SBB-ZnO3, CRHB, and CRHB-ZnO3 were analyzed. Results indicate that SB- and CRH-derived biochars with a ZnO nanoparticle loading ratio of 3 wt% could generate maximum adsorption capacities of RR24 thanks to the double growth on the BET surface of modified biochars. The RR24 adsorption capacities of CRHB-ZnO3 and SBB-ZnO3 reached 81.04 and 105.24 mg g -1 , respectively, which were much higher than those of pristine CRHB and SBB (66.19 and 76.14, respectively) at an initial RR24 concentration of 250 mg L -1 , pH 3, and contact time of 60 min. The adsorption of RR24 onto biochars agreed well with the pseudo-first-order model and the Langmuir isotherm. The RR24 adsorption capacity on modified biochars, which were reused after five adsorption-desorption cycles showed no insignificant drop. The main adsorption mechanisms of RR24 onto biochars were controlled by electrostatic interactions between biochars' surface positively charged functional groups with azo dye anions, pore filling, hydrogen bonding formation, and π-π interaction., Competing Interests: The authors declare that they have no conflict of interest., (This journal is © The Royal Society of Chemistry.)

The clinical analysis of cases of bacteremia is valuable. However, limited data on bacteremia are available in Vietnam. We conducted a single-center retrospective surveillance study at the Bach Mai Hospital, Hanoi, Vietnam between 2009 and 2012. In total, 45,366 blood cultures were analyzed. The number of blood cultures per 1,000 patient-days was 9.59 sets. The percentage of solitary blood culture sets was 49.6%, and the rate of positive blood cultures was 13.9%. The major pathogens isolated in adults were coagulase-negative Staphylococcus species (16.7%), followed by Escherichia coli (6.8%), Streptococcus spp. excluding Streptococcus pneumoniae (3.8%), and Staphylococcus aureus (5.2%). Other major pathogens identified were Klebsiella spp. (4.2%) and Acinetobacter spp. (2.2%). The number of blood cultures per 1,000 patient-days was lower and the percentage of solitary blood culture sets higher than that of a Japanese study (9.6 vs. 25.2 and 49.6% vs. 32.8%, respectively). The distribution of microorganisms was unique in terms of the relative predominance of cases of Acinetobacter bacteremia. The percentage of cases of healthcare-associated bacteremia may be relatively high.

Type 2 diabetes (T2D) is a complex disorder resulting from both genetic and environmental factors in its pathogenesis. A case-control study was designed with subjects recruited from a general population to investigate whether the association between T2D and the common T>A polymorphism (rs9939609) in fat mass and obesity associated (FTO) gene is mediated by obesity-related measurements, considering the contribution of socio-economic status and lifestyle factors. The significant association between the FTO rs9939609 polymorphism and T2D was first observed in the model unadjusted (OR per A allele=1.61, 95% CI=1.06-2.44, P=0.024). It remained consistently replicated in the final model after adjustments for sex, age, systolic blood pressure, socio-economic status, lifestyle factors, and obesity-related measurements (body mass index, waist-hip ratio, body fat percentage, and body adiposity index), showing an increased T2D risk with an additive effect of the alleles (ORs per A allele=1.80-1.92, 95% CI=1.09-3.19, P<0.05). The FTO-rs9939609 polymorphism, systolic blood pressure, and waist-hip ratio were the most significant independent predictors for T2D, in which the power of the adjusted prediction model was 0.769. In conclusion, the study suggested that the FTO-rs9939609 polymorphism was significantly associated with the increased risk of T2D, independent of obesity-related measurements in a Vietnamese population., (Copyright © 2012 Elsevier B.V. All rights reserved.)