Effective La-doped SrTiO3 (Sr1−xLaxTiO3, x = 0–0.1 mol.% La-doped) nanocubes were successfully synthesized by a hydrothermal method. The influence of different La dopant concentrations on the ...physicochemical properties of the host structure of SrTiO3 was fully characterized. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) revealed that the Sr2+ in the crystal lattice of SrTiO3 was substituted by La3+. As a result, the absorption region of the Sr1−xLaxTiO3 could be extended to visible light. Scanning electron microscopy (SEM) images confirmed that their morphologies are associated with an increased surface area and an increased La-doping concentration. The decrease in the photoluminescence (PL) intensity of the dopant samples showed more defect levels created by the dopant La+3 cations in the SrTiO3 structure. The photocatalytic activities of Sr1−xLaxTiO3 were evaluated with regard to the degradation of 2-naphthol at typical conditions under artificial solar light. Among the candidates, Sr0.95La0.05TiO3 exhibited the highest photocatalytic performance for the degradation of 2-naphthol, which reached 92% degradation efficiency, corresponding to a 0.0196 min−1 degradation rate constant, within 180 minutes of irradiation. Manipulating the structure of Sr1−xLaxTiO3 nanocubes could produce a more effective and stable degradation efficiency than their parent compound, SrTiO3. The parameters remarkably influence the Sr1−xLaxTiO3 nanocubes’ structure, and their degradation efficiencies were also studied. Undoubtedly, substantial breakthroughs of Sr1−xLaxTiO3 nanocube photocatalysts toward the treatment of organic contaminants from industrial wastewater are expected shortly.
Summary
Bats and rodents are being increasingly recognized as reservoirs of emerging zoonotic viruses. Various studies have investigated bat viruses in tropical regions, but to date there are no data ...regarding viruses with zoonotic potential that circulate in bat and rat populations in Viet Nam. To address this paucity of data, we sampled three bat farms and three wet markets trading in rat meat in the Mekong Delta region of southern Viet Nam. Faecal and urine samples were screened for the presence of RNA from paramyxoviruses, coronaviruses and filoviruses. Paramyxovirus RNA was detected in 4 of 248 (1%) and 11 of 222 (4.9%) bat faecal and urine samples, respectively. Coronavirus RNA was detected in 55 of 248 (22%) of bat faecal samples; filovirus RNA was not detected in any of the bat samples. Further, coronavirus RNA was detected in 12 of 270 (4.4%) of rat faecal samples; all samples tested negative for paramyxovirus. Phylogenetic analysis revealed that the bat paramyxoviruses and bat and rat coronaviruses were related to viruses circulating in bat and rodent populations globally, but showed no cross‐species mixing of viruses between bat and rat populations within Viet Nam. Our study shows that potentially novel variants of paramyxoviruses and coronaviruses commonly circulate in bat and rat populations in Viet Nam. Further characterization of the viruses and additional human and animal surveillance is required to evaluate the likelihood of viral spillover and to assess whether these viruses pose a risk to human health.
Rodents and bats are now widely recognised as important sources of zoonotic virus infections in other mammals, including humans. Numerous surveys have expanded our knowledge of diverse viruses in a ...range of rodent and bat species, including their origins, evolution, and range of hosts. In this study of pegivirus and human hepatitis-related viruses, liver and serum samples from Vietnamese rodents and bats were examined by PCR and sequencing. Nucleic acids homologous to human hepatitis B, C, E viruses were detected in liver samples of 2 (1.3%) of 157 bats, 38 (8.1%), and 14 (3%) of 470 rodents, respectively. Hepacivirus-like viruses were frequently detected (42.7%) in the bamboo rat,
, while pegivirus RNA was only evident in 2 (0.3%) of 638 rodent serum samples. Complete or near-complete genome sequences of HBV, HEV and pegivirus homologues closely resembled those previously reported from rodents and bats. However, complete coding region sequences of the rodent hepacivirus-like viruses substantially diverged from all of the currently classified variants and potentially represent a new species in the
genus. Of the viruses identified, their routes of transmission and potential to establish zoonoses remain to be determined.
The highest burden of disease from hepatitis C virus (HCV) is found in Southeast Asia, but our understanding of the epidemiology of infection in many heavily burdened countries is still limited. In ...particular, there is relatively little data on acute HCV infection, the outcome of which can be influenced by both viral and host genetics which differ within the region. We studied HCV genotype and IL28B gene polymorphism in a cohort of acute HCV-infected patients in Southern Vietnam alongside two other cohorts of chronic HCV-infected patients to better understand the epidemiology of HCV infection locally and inform the development of programs for therapy with the increasing availability of directly acting antiviral therapy (DAAs).
We analysed plasma samples from patients with acute and chronic HCV infection, including chronic HCV mono-infection and chronic Human Immunodeficiency Virus (HIV)-HCV coinfection, who enrolled in four epidemiological or clinical research studies. HCV infection was confirmed with RNA testing. The 5' UTR, core and NSB5 regions of HCV RNA positive samples were sequenced, and the genotype and subtype of the viral strains were determined. Host DNA from all HCV positive patients and age- and sex-matched non-HCV-infected control individuals were analysed for IL28B single nucleotide polymorphism (SNP) (rs12979860 and rs8099917). Geolocation of the patients were mapped using QGIS.
355 HCV antibody positive patients were analysed; 54.6% (194/355) and 46.4% (161/355) were acute and chronic infections, respectively. 50.4% (81/161) and 49.6.4% (80/161) of chronic infections had HCV mono-infection and HIV-HCV coinfection, respectively. 88.7% (315/355) and 10.1% (36/355) of the patients were from southern and central regions of Vietnam, respectively. 92.4% (328/355) of patients were HCV RNA positive, including 86.1% (167/194) acute and 100% (161/161) chronic infections. Genotype could be determined in 98.4% (322/328) patients. Genotypes 1 (56.5%; 182/322) and 6 (33.9%; 109/322) predominated. Genotype 1 including genotype 1a was significantly higher in HIV-HCV coinfected patients compared to acute HCV patients 43.8% (35/80) versus 20.5% (33/167), (p = <0.001), while genotype 6 was significantly higher in chronic HCV mono-infected patients (44.4% (36/81) versus 20.0% (16/80) (p = < 0.004) compared to HIV-HCV coinfected patients. The prevalence of IL28B SNP (rs12979860) homozygous CC was 86.46% (83/96) in control individuals and was significantly higher in acutely-infected compared to chronically-infected patients 93.2 (82/88) versus 76.1% (35/46) (p = < 0.005).
HCV genotype 6 is highly prevalent in Vietnam and the high prevalence in treatment naïve chronic HCV patients may results from poor spontaneous clearance of acute HCV infection with genotype 6.
The
family of viruses encompasses a group of pathogens with a zoonotic potential as observed from previous outbreaks of the severe acute respiratory syndrome coronavirus and Middle East respiratory ...syndrome coronavirus. Accordingly, it seems important to identify and document the coronaviruses in animal reservoirs, many of which are uncharacterized and potentially missed by more standard diagnostic assays. A combination of sensitive deep sequencing technology and computational algorithms is essential for virus surveillance, especially for characterizing novel- or distantly related virus strains. Here, we explore the use of profile Hidden Markov Model-defined Pfam protein domains (Pfam domains) encoded by new sequences as a
sequence classification tool. The encoded domains are used first in a triage to identify potential
sequences and then processed using a Random Forest method to classify the sequences to the
genus level. The application of this algorithm on
genomes assembled from agnostic deep sequencing data from surveillance of bats and rats in Dong Thap province (Vietnam) identified thirty-four
and eleven
genomes. This collection of bat and rat coronaviruses genomes provided essential information on the local diversity of coronaviruses and substantially expanded the number of coronavirus full genomes available from bat and rats and may facilitate further molecular studies on this group of viruses.
Summary
Viral pathogens account for a significant proportion of the burden of emerging infectious diseases in humans. The Wellcome Trust‐Vietnamese Initiative on Zoonotic Infections (WT‐VIZIONS) is ...aiming to understand the circulation of viral zoonotic pathogens in animals that pose a potential risk to human health. Evidence suggests that human exposure and infections with hepatitis E virus (HEV) genotypes (GT) 3 and 4 results from zoonotic transmission. Hypothesising that HEV GT3 and GT4 are circulating in the Vietnamese pig population and can be transmitted to humans, we aimed to estimate the seroprevalence of HEV exposure in a population of farmers and the general population. We additionally performed sequence analysis of HEV in pig populations in the same region to address knowledge gaps regarding HEV circulation and to evaluate if pigs were a potential source of HEV exposure. We found a high prevalence of HEV GT3 viral RNA in pigs (19.1% in faecal samples and 8.2% in rectal swabs) and a high HEV seroprevalence in pig farmers (16.0%) and a hospital‐attending population (31.7%) in southern Vietnam. The hospital population was recruited as a general‐population proxy even though this particular population subgroup may introduce bias. The detection of HEV RNA in pigs indicates that HEV may be a zoonotic disease risk in this location, although a larger sample size is required to infer an association between HEV positivity in pigs and seroprevalence in humans.
A new compound, conamonin A (
), was isolated from the whole plants of
with eight known dihydrochalcones (
-
). Their structures were elucidated by a combination of spectroscopic methods as well as ...by comparison with previously reported data. The absolute configuration of
was assigned by TDDFT-ECD method. Compounds
and
showed inhibitory activity against LPS-induced NO production in the RAW 264.7 cells, with IC
values of 58.29 ± 2.88 and 81.77 ± 5.99 μM, respectively. Compounds
and
exhibited inhibitory effects, with IC
values of 28.76 ± 1.16 and 29.89 ± 1.79 μg/mL, respectively. Compounds
,
-
exhibited significant cytotoxic activity against human lung carcinoma (the SK-LU-1 cell line) with IC
values ranging from 9.87 to 17.99 µM. This study offers valuable insights into the chemical constituents and biological activities of
, highlighting its potential as a source for discovering new anti-inflammatory and cytotoxic agents.
Background: Hazard analysis and critical control points (HACCP) is a tool for food safety assurance, but the application of HACCP in healthcare facilities in Vietnam has been understudied and ...underregulated given a lack of governmental guidelines. This study aimed to explore the hazards and determine the critical control points related to the parenteral nutrition (PN) preparation procedures in a pediatric hospital in Vietnam. Methods: A cross-sectional study was conducted at Children Hospital No. 2 in Ho Chi Minh City, Vietnam, from July to September 2019. The study subjects were eleven standard operating procedures for preparation of a PN product called Vaminolact 6.5%. The hazards were explored based on the probability of occurrence, the severity of consequence, and the quantity of influenced individuals. Each step in the PN procedure was determined by multiplying the points of three standards. A step with a point equal to or higher than 18 was considered a hazard. The critical control point (CCP) was determined by following the five-question decision tree. Results: Eight hazards were explored via hazard analysis, including sanitation prior to compounding, measurement of basal solution, compounding, labeling, sanitation of preparation room, in-out control, air flow control, and primary filter system. Nine critical control points were determined as follows: sterilization by alcohol, glove change per every 10 vials, basal solution measurement, compounding, mini-spike change per every 10 vials, syringe change per every 10 vials, air flow control, primary filter system, and sterilization check-up. Conclusion: The hospital manager should consider this study as support for an evidence-based adjustment to improve PN preparation procedure.
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