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Since the end of the 1990s, unexplained outbreaks of acute encephalitis in children coinciding with litchi harvesting (May-July) have been documented in the Bac Giang Province in northern Vietnam. A retrospective ecologic analysis of data for 2004-2009 involving environmental, agronomic, and climatic factors was conducted to investigate the suspected association between the outbreaks and litchi harvesting. The clinical, biological, and immunologic characteristics of the patients suggested a viral etiology. The ecologic study revealed an independent association between litchi plantation surface proportion and acute encephalitis incidence: Incidence rate ratios were 1.52 (95% CI 0.90-2.57), 2.94 (95% CI 1.88-4.60), and 2.76 (95% CI 1.76-4.32) for second, third, and fourth quartiles, respectively, compared with the lowest quartile. This ecologic study confirmed the suspected association between incidence of acute encephalitis and litchi plantations and should be followed by other studies to identify the causative agent for this syndrome. [ABSTRACT FROM AUTHOR]

Background: HIV prevalence among sex workers in Ho Chi Minh City has increased rapidly, from 6.5% in 1999 to 18.1% in 2000. This study examined whether injecting drug use among street-based sex workers (SSWs) in Ho Chi Minh City is a high-risk factor for HIV infection. Goal: The goal of this study was to determine the correlates and prevalence of intravenous drug users among SSWs in Ho Chi Minh City. Study Design: A cross-sectional study was conducted among SSWs in Ho Chi Minh City during December 2000. The SSWs were interviewed and tested for HIV-1. Results: HIV-1 seroprevalence was 16.3%. Regression analysis indicated that injecting drugs and being younger than 25 years of age were independently associated with HIV seropositivity. Conclusion: Young SSWs who inject drugs are at the greatest risk of contracting HIV and acting as a bridge for HIV to the sexually active population. [ABSTRACT FROM AUTHOR]

A qualitative study was conducted among drug users in Hanoi, Vietnam in May and June 2001 to describe their drug use practices and sexual behaviours, as well as potential factors that might contribute to the recent increase of HIV among them and local sex workers. A total of 63 drug users in five main districts of Hanoi were recruited for in-depth interviews and focus group discussions. The study found that drug users in Hanoi have been engaging in high-risk injecting behaviours and practices. They reported frequently visiting female sex workers (FSWs) and low condom use. Drug users had poor understanding and practices of cleaning injecting equipment, little knowledge of infection through sexual routes, and infrequent knowledge of their HIV infection status. The study provided evidence that young and new injecting drug users (IDUs) are at particularly high risk of HIV infection, are sexually active, and can serve as a bridge between the drug user and FSWs populations. They and sex workers should be the focus of intervention activities. [ABSTRACT FROM AUTHOR]

To examine the causes of a rapid increase of HIV infection among female sex workers (FSWs) in Hanoi, Viet Nam, a qualitative study of sex workers was conducted there in June 2001 to study their risk characteristics, their relationships with drug users, and to identify potential factors playing a role in the recent rise of HIV. Thirty-seven FSWs in different districts were recruited for in-depth interviews and group discussions about drug use and sexual behaviour. They reported higher condom use with irregular clients, although use was still low with regular clients and their love mates. Drug use is common, and many FSWs inject, especially street-based sex workers. There are interactions between drug users and FSWs through both injecting and unsafe sexual contact. Drug-injecting street-based FSWs are the highest risk sex worker group for HIV infection, and potentially serve as a major bridge through their clients to the general population. Prevention of HIV transmission will depend on the risk behaviour of the general population and the success of intervention strategies targeting FSWs, especially street-based FSWs and those injecting drugs. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To study patterns and determinants of HIV prevalence and risk-behaviour characteristics in different population groups in four border provinces of Viet Nam. METHODS: We surveyed four population groups during April-June 2002. We used stratified random-cluster sampling and collected data concomitantly on HIV status and risk behaviours. The groups included were female sex workers (n = 2023), injecting drug users (n = 1391), unmarried males aged 15-24 years (n = 1885) and different categories of mobile groups (n = 1923). FINDINGS: We found marked geographical contrasts in HIV prevalence, particularly among female sex workers (range 0-24%). The HIV prevalence among injecting drug users varied at high levels in all provinces (range 4-36%), whereas lower prevalences were found among both unmarried young men (range 0-1.3%) and mobile groups (range 0-2.5%). All groups reported sex with female sex workers. Less than 40% of the female sex workers had used condoms consistently. The strongest determinants of HIV infection among female sex workers were inconsistent condom use (adjusted odds ratio [OR], 5.3; 95% confidence interval [CI], 2.4-11.8), history of injecting drug use and mobility, and, among injecting drug users, sharing of injection equipment (adjusted OR, 7.3; 95% CI, 2.3-24.0) and sex with non-regular partners (adjusted OR 3.4; 95% CI 1.4-8.5). CONCLUSION: The finding of marked geographical variation in HIV prevalence underscores the value of understanding local contexts in the prevention of HIV infection. Although lacking support from data from all provinces, there would appear to be a potential for sex work to drive a self-sustaining heterosexual epidemic. That the close links to serious injecting drug use epidemics can have an accelerating effect in increasing the spread of HIV merits further study. Copyright © 2007 World Health Organization [ABSTRACT FROM AUTHOR]

Background: Vulvovaginal candidiasis and urinary tract infections caused by Candida are common diseases. While the most common causative agent is C. albicans , other species, such as non- C. albicans , can also be responsible. Susceptibility to antifungal drugs varies among Candida species, but there is very limited information available from Vietnam., Objectives: To determine the species distribution and antifungal susceptibility patterns of Candida isolated from urine and vaginal samples of patients tested at the Medlatec healthcare system in 2023., Design: Cross-sectional study., Methods: The study describes a cross-sectional analysis of over 102 Candida isolates obtained from urine and vaginal samples of patients using the testing services at Vietnam Medlatec healthcare system from January to December 2023. Species identification of Candida isolates was performed using germ tube test and Vitek ® 2 systems. Antifungal susceptibility testing was carried out using the VITEK ® 2 card for yeast fungi. Minimum inhibitory concentrations for these isolates were classified according to the Clinical and Laboratory Standards Institute guidelines (M27-A3 and M27M44S-ED3)., Results: In this investigation, five different Candida species were identified. Among these isolates, C. albicans (78.43%) was the most frequent, followed by C. tropicalis (11.76%), C. glabrata (4.91%), C. parapsilosis (1.96%), and C. krusei (0.98%). The resistance rates to fluconazole, voriconazole, caspofungin, micafungin, and amphotericin B were 7.7%, 4.2%, 4.0%, 1.0% and 1.0%, respectively., Conclusion: The most common species found in this population was C. albicans . Our findings also showed a high frequency of non- albicans Candida species causing fungal urinary tract infections. The resistance rates of isolated Candida strains to echinocandins and amphotericin B were low, while some strains were found to be resistant to fluconazole and voriconazole., (© The Author(s), 2025.)

This article studies the synthesis, as well as the structural, vibrational, and optical properties of Eu 3+ -doped ZnO quantum dots (QDs) and investigates the energy transfer mechanism from the ZnO host to Eu 3+ ions using Reisfeld's approximation. Eu 3+ -doped ZnO QDs at varying concentrations (0-7%) were successfully prepared using a wet chemical method. The successful doping of Eu 3+ ions into the ZnO host lattice, as well as the composition and valence states of the elements present in the sample, were confirmed through X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses. XRD results demonstrated the crystalline nature of the ZnO QDs, revealing their wurtzite (WZ) structure with no secondary phases. XPS analysis provided further confirmation of the presence of Eu 3+ ions within the ZnO host, with clear signals corresponding to the Zn, O, and Eu elements. The valence states of Eu were verified as trivalent (Eu 3+ ), confirming the successful doping of Eu 3+ ions, as evidenced by the characteristic Eu 3d peaks in the XPS spectra. Raman spectroscopy (RS) was employed to analyze the vibrational modes, revealing shifts in ZnO lattice vibrations due to Eu 3+ incorporation, indicating strong coupling between Eu 3+ ions and the ZnO host. Optical properties were studied using UV-Vis absorption, photoluminescence (PL) spectroscopy, and PL decay spectroscopy, showing a significant enhancement of red emission, attributed to the 5 D 0 → 7 F 2 transition of Eu 3+ ions under UV excitation. Using Judd-Ofelt (JO) analysis, the intensity parameters ( Ω 2 , Ω 4 , Ω 6 ) were derived, providing insights into the asymmetry of the Eu 3+ ion's local environment and the radiative transition probabilities. Energy transfer processes between the ZnO host and Eu 3+ dopants were examined, showing efficient sensitization of Eu 3+ through excitation of the ZnO host, with an optimal Eu 3+ doping level maximizing luminescence. Eu 3+ -doped ZnO QDs, which emit in the visible light region and are non-toxic, have great potential for applications in photonic devices, light-emitting diodes, and bioimaging., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A pyruvate dehydrogenase complex deficiency causes a reduction in adenosine triphosphate production and energy insufficiency, leading to neurological disorders. An abnormal E1-alpha protein originating from the PDHA1 gene with pathogenic variants is unable to communicate with E1-beta for the formation of the E1 enzyme, decreasing pyruvate dehydrogenase complex activity. In this study, we report a Vietnamese boy with lethargy, severe metabolic acidosis, increased serum lactate, hyperalaninemia, lactic acidosis, and globus pallidus lesions. Whole-exome sequencing and variant filtering identified a hemizygous missense variant NM000284.4 ( PDHA1 ): c.479T>G (p.Phe160Cys) in the patient. The variant c.479T>G caused a single nucleotide substitution on exon 5 and was predicted to be a disease-causing variant in the in silico analyses. We present the first report with a genetic analysis of a Vietnamese patient with pyruvate dehydrogenase E1-alpha deficiency (PDHAD). Sanger sequencing demonstrated that the patient inherited the variant from his mother who harbored the variant in a heterozygous state, but no PDHAD symptoms were observed in her. In addition, a prenatal test of the patient's mother revealed a fetus with a normal genotype. Furthermore, the patient's father and sister both carried a normal allele. Based on the American College of Medical Genetics criteria, the variant c.479T>G was predicted to be a likely pathogenic variant. Using the combination of the patient's genotype and phenotype, he was definitively diagnosed with pyruvate dehydrogenase E1-alpha deficiency. Our findings expand the mutational spectrum of neurological disorders and provide the scientific basis for genetic counseling for the patient's family., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Nguyen, Khanh, Vu, Nguyen, Tran, Lien, Van Tung, Quan, Hien, Giang, Xuan, Tao, Khoa and Nguyen.)

Specialized or secondary metabolites are small molecules of biological origin, often showing potent biological activities with applications in agriculture, engineering and medicine. Usually, the biosynthesis of these natural products is governed by sets of co-regulated and physically clustered genes known as biosynthetic gene clusters (BGCs). To share information about BGCs in a standardized and machine-readable way, the Minimum Information about a Biosynthetic Gene cluster (MIBiG) data standard and repository was initiated in 2015. Since its conception, MIBiG has been regularly updated to expand data coverage and remain up to date with innovations in natural product research. Here, we describe MIBiG version 4.0, an extensive update to the data repository and the underlying data standard. In a massive community annotation effort, 267 contributors performed 8304 edits, creating 557 new entries and modifying 590 existing entries, resulting in a new total of 3059 curated entries in MIBiG. Particular attention was paid to ensuring high data quality, with automated data validation using a newly developed custom submission portal prototype, paired with a novel peer-reviewing model. MIBiG 4.0 also takes steps towards a rolling release model and a broader involvement of the scientific community. MIBiG 4.0 is accessible online at https://mibig.secondarymetabolites.org/., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Background : Cardiomyopathy, including dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM), is a major cause of heart failure (HF) and a leading indication for heart transplantation. Of these patients, 20-50% have a genetic cause, so understanding the genetic basis of cardiomyopathy will provide knowledge about the pathogenesis of the disease for diagnosis, treatment, prevention, and genetic counseling for families. Methods : This study collected nine patients from different Vietnamese families for genetic analysis at The Cardiovascular Center, E Hospital, Hanoi, Vietnam. The patients were diagnosed with cardiomyopathy based on clinical symptoms. Whole-exome sequencing (WES) was performed in the Vietnamese patients to identify variants associated with cardiomyopathy, and the Sanger sequencing method was used to validate the variants in the patients' families. The influence of the variants was predicted using in silico analysis tools. Results : Nine heterozygous variants were detected as a cause of disease in the patients, three of which were novel variants, including c.284C>G, p.Pro95Arg in the MYL2 gene, c.2356A>G, p.Thr786Ala in the MYH7 gene, and c.1223T>A, p.Leu408Gln in the DES gene. Two other variants were pathogenic variants (c.602T>C, p.Ile201Thr in the MYH7 gene and c.1391G>C, p.Gly464Ala in the PTPN11 gene), and four were variants of uncertain significance in the ACTA2 , ANK2 , MYOZ2 , and PRKAG2 genes. The results of the in silico prediction software showed that the identified variants were pathogenic and responsible for the patients' DCM. Conclusions : Our results contribute to the understanding of cardiomyopathy pathogenesis and provide a basis for diagnosis, treatment, prevention, and genetic counseling.

CdSe quantum dots (QDs) with size in the range of 3.5-5.8 nm and a zinc blende (ZB) crystal structure were synthesized by the wet chemical method. The morphology of the synthesized QDs was assessed by transmission electron microscopy (TEM). The structural and optical properties were characterized by X-ray diffraction (XRD), absorption spectroscopy (Abs) and photoluminescence (PL) spectroscopy. The anti-cancer activity of CdSe QDs was investigated on AGS gastric cancer cells through cell viability screening (MTT assay), cell cycle and apoptosis analysis using flow cytometry. The generation of reactive oxygen species (ROS) was analyzed using the cell fluorescence staining method with H2DCFDA. Three QD series of CdSe1 (3.5 nm), CdSe2 (4.7 nm) and CdSe3 (5.8 nm) have been selected to study their effects on the extermination of stomach cancer cells. The CdSe QDs all exhibited the potential to induce toxicity to cells at concentrations ranging from 5 to 20 μg mL -1 . CdSe2 demonstrated a significant impact on cell proliferation compared to the CdSe1 and CdSe3 forms ( p < 0.01). CdSe QDs caused cell cycle arrest, leading to the accumulation of cells in the G0/G1 phase, while also increasing the rate of apoptosis compared to the control ( p < 0.01). More importantly, it has been demonstrated that CdSe QDs promote excessive production of ROS in AGS cells, which is believed to be the cause of apoptosis and the reduction of cell proliferation. These data suggest that CdSe QDs are a good candidate for combating gastric cancer cells., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this study, Eu 3+ ion singly doped and Eu 3+ /Sm 3+ ions co-doped ZnS semiconductor quantum dots (QDs) were successfully synthesized using a wet chemical method in 1-octadecene (ODE) solvent. The successful doping of Sm 3+ and Eu 3+ ions into the ZnS host lattice and the composition and valence of the elements present in the sample were confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Structural and morphological studies revealed the presence of Eu 3+ -doped ZnS and Eu 3+ /Sm 3+ co-doped ZnS QDs of about 3-4 nm size with a zinc blende structure. The Judd-Ofelt (J-O) intensity parameters of Eu 3+ -doped ZnS QDs were determined from their fluorescence spectra. The optical properties of Eu 3+ /Sm 3+ co-doped ZnS QDs were studied by changing the Eu 3+ ion concentration and fixing the Sm 3+ ion concentration. The photoluminescence (PL) spectra of Eu 3+ /Sm 3+ co-doped ZnS QDs were obtained at an excitation wavelength of 403 nm ( 6 H 5/2 → 6 P 3/2 transition of Sm 3+ ions) in the 525-725 nm range. The effective energy transfer (ET) process from Sm 3+ to Eu 3+ ions was confirmed and explained in detail using the Reisfeld approximation and the Inokuti-Hirayama model. The CIE color coordinates of the Eu 3+ /Sm 3+ co-doped ZnS QDs were obtained using PL spectral data. Eu 3+ /Sm 3+ co-doped ZnS QDs exhibited a long lifetime and emitted warm red light. These interesting properties give Eu 3+ /Sm 3+ co-doped ZnS QDs great potential for applications in photovoltaics, photocatalysis, and biomarkers.

In this work, the volatile components of Erigeron sublyratus essential oils and their anti-inflammatory and cytotoxic activities were investigated for the first time. Gas chromatography-mass spectrometry (GC-MS) analysis identified 28 components in the root and aerial part essential oils. The main components included cis-lachnophyllum ester (53.4-64.2 %), germacrene D (5.6-8.6 %), trans-β-ocimene (2.6-7.5 %), β-caryophyllene (4.7-6.8 %), β-myrcene (2.0-6.3 %), and (E)-β-farnesene (4.8-5.0 %). The aerial part essential oil inhibited nitric oxide (NO) production on LPS-induced RAW 264.7 cells, with an IC 50 value of 1.41±0.10 μg/mL. In addition, both root and aerial part essential oils exhibited cytotoxic activity against MCF-7, SK-LU-1, and HepG2. Molecular docking simulation results revealed that (E)-β-farnesene strongly binds to the VEGFR-2 enzyme, while δ-cadinene has a high affinity to the COX-2 enzyme via hydrophobic interactions. These findings proposed that E. sublyratus essential oils can be exploited for their anti-inflammatory and anti-cytotoxicity potential., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

From 2011 to 2012, Northern Vietnam suffered its first large-scale hand, foot, and mouth disease (HFMD) epidemic. Two sets of official guidelines were issued during the outbreak to handle the HFMD crisis. The city of Hai Phong was used as a model to analyze the impact of the released guidelines. A total of 9621 HFMD cases were reported in Hai Phong city from April 2011 to December 2012. Three distinct waves of HFMD occurred. Enterovirus A71 and Coxsackievirus A16 were successively associated with the epidemics. Two periods, before and after the guidelines' release, could be distinguished and characterized by different patient patterns. The time to admission and severity changed notably. Guideline publications help the health system refocus on the 0.5-3 years age group with the highest incidence of the disease. The three waves showed different special distribution, but the main routes of infection were rivers and local secondary roads, most likely through local trade and occupational movements of people.

CoAl 2 O 4 : x Dy 3+ nanocrystals ( x = 0, 0.1, 0.5, 1.0, and 3.0 mol%) with spinel structures were prepared using the co-precipitation method. The crystal structure, optical properties, and presence of elements were respectively analyzed using X-ray diffraction, photoluminescence excitation, photoluminescence spectra, luminescence lifetime, and X-ray photoelectron spectroscopy. The influence of temperature on material fabrication was studied using differential scanning calorimetry and thermogravimetric techniques. The color characteristics of Dy 3+ luminescence in the CoAl 2 O 4 host were evaluated using CIE chromaticity coordinates and correlated color temperature. For the first time, the electronic dipole transitions in the photoluminescence excitation spectra were used to calculate the optical parameters of Dy 3+ ions in the CoAl 2 O 4 host using Judd-Ofelt theory. The Inokuti-Hirayama model was used to explain the energy transfer process between Dy 3+ ions, the main interaction mechanism, and energy transfer parameters for the luminescence of Dy 3+ ions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

An HFMD outbreak spread over the city of Hải Phòng from summer 2011 to autumn 2012. This epidemic was chosen because it was the very first HFMD epidemic in North Vietnam, eliminating thus interferences with previous outbreaks. This epidemic displayed three separate waves. A complete dataset was collected for more than 9500 patients during this period, which enabled us to analyze this epidemic at different scales. Access to the healthcare system was crucial during this period, which was possible due to a reorganization of the system in February-March 2012. An analysis at the commune level enabled us to track the epidemic along certain communication routes. The three-waves structure reveals a wide disparity at the district level. We developed a mathematical model showing high accuracy at the adjustment of data for both the total number of cases and for the number of cases per week. As a consequence, the model was able to accurately determine the dates of the beginning and end of each wave and to show that they overlapped. Using mathematical functions associated with this model, it was possible to calculate the probability for a patient to belong to a specific wave., Competing Interests: The authors declare no conflict of interest.

Background: Nature has perennially served as an infinite reservoir of diverse chemicals with numerous applications benefiting humankind. In recent years, due to the emerging COVID-19 pandemic, there has been a surge in studies on repurposing natural products as anti-SARS-CoV-2 agents, including plant-derived substances. Among all types of natural products, alkaloids remain one of the most important groups with various known medicinal values. The current investigation focuses on Amaryllidaceae alkaloids (AAs) since AAs have drawn significant scientific attention as anti-SARS-CoV-2 agents over the past few years., Purpose and Study Design: This study serves as a mini-review, summarizing recent advances in studying the anti-SARS-CoV-2 potency of AAs, covering two aspects: structure-activity relationship and mechanism of action (MOA)., Methods: The study covers the period from 2019 to 2023. The information in this review were retrieved from common databases including Web of Science, ScienceDirect, PubMed and Google scholar. Reported anti-SARS-CoV-2 potency, cytotoxicity and possible biological targets of AAs were summarized and classified into different skeletal subclasses. Then, the structure-activity relationship (SAR) was explored, pinpointing the key pharmacophore-related structural moieties. To study the mechanism of action of anti-SARS-CoV-2 AAs, possible biological targets were discussed., Results: In total, fourteen research articles about anti-SARS-CoV-2 was selected. From the SAR point of view, four skeletal subclasses of AAs (lycorine-, galanthamine-, crinine- and homolycorine-types) appear to be promising for further investigation as anti-SARS-CoV-2 agents despite experimental inconsistencies in determining in vitro half maximal inhibitory effective concentration (EC 50 ). Narciclasine, haemanthamine- and montanine-type skeletons were cytotoxic and devoid of anti-SARS-CoV-2 activity. The lycorine-type scaffold was the most structurally diverse in this study and preliminary structure-activity relationships revealed the crucial role of ring C and substituents on rings A, C and D in its anti-SARS-CoV-2 activity. It also appears that two enantiomeric skeletons (haemanthamine- and crinine-types) displayed opposite activity/toxicity profiles regarding anti-SARS-CoV-2 activity. Pharmacophore-related moieties of the haemanthamine/crinine-type skeletons were the substituents on rings B, C and the dioxymethylene moiety. All galanthamine-type alkaloids in this study were devoid of cytotoxicity and it appears that varying substituents on rings C and D could enhance the anti-SARS-CoV-2 potency. Regarding MOAs, initial experimental results suggested Mpro and RdRp as possible viral targets. Dual functionality between anti-inflammatory activity on host cells and anti-SARS-CoV-2 activity on the SARS-CoV-2 virus of isoquinoline alkaloids, including AAs, were suggested as the possible MOAs to alleviate severe complications in COVID-19 patients. This dual functionality was proposed to be related to the p38 MAPK signaling pathway., Conclusion: Overall, Amaryllidaceae alkaloids appear to be promising for further investigation as anti-SARS-CoV-2 agents. The skeletal subclasses holding the premise for further investigation are lycorine-, crinine-, galanthamine- and homolycorine-types., Competing Interests: Declaration of competing interest 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., (Copyright © 2024. Published by Elsevier GmbH.)

Talaromyces sp. DC2 is an endophytic fungus that was isolated from the stem of Catharanthus roseus (L.) G. Don in Hanoi, Vietnam and is capable of producing vinca alkaloids. This study utilizes the PacBio Sequel technology to completely sequence the whole genome of Talaromyces sp. DC2The genome study revealed that DC2 contains a total of 34.58 Mb spanned by 156 contigs, with a GC content of 46.5%. The identification and prediction of functional protein-coding genes, tRNA, and rRNA were comprehensively predicted and highly annotated using various BLAST databases, including non-redundant (Nr) protein sequence, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Clusters of Orthologous Groups (COG), and Carbohydrate-Active Enzymes (CAZy) databases. The genome of DC2 has a total of 149, 227, 65, 153, 53, and 6 genes responsible for cellulose, hemicellulose, lignin, pectin, chitin, starch, and inulin degradation, respectively. The Antibiotics and Secondary Metabolites Analysis Shell (AntiSMASH) analyses revealed that strain DC2 possesses 20 biosynthetic gene clusters responsible for producing secondary metabolites. The strain DC2 has also been found to harbor the DDC gene encoding aromatic L-amino acid decarboxylase enzyme. Conclusively, this study has provided a comprehensive understanding of the processes involved in secondary metabolites and the ability of the Talaromyces sp. DC2 strain to degrade plant cell walls.

Schistosomiasis is a parasitic disease that endangers human health and social development. The granulomatous reaction of Schistosoma eggs in the liver is the main cause of hepatosplenomegaly and fibrotic lesions. Anti liver fibrosis therapy is crucial for patients with chronic schistosomiasis. Although Praziquantel is the only clinical drug used, it is limited in insecticide treatment and has a long-term large-scale use, which is forcing the search for cost-effective alternatives. Previous research has demonstrated that plant metabolites and extracts have effective therapeutic effects on liver fibrosis associated with schistosomiasis. This paper summarizes the mechanisms of action of metabolites and some plant extracts in alleviating schistosomiasis-associated liver fibrosis. The analysis was conducted using databases such as PubMed, Google Scholar, and China National Knowledge Infrastructure (CNKI) databases. Some plant metabolites and extracts ameliorate liver fibrosis by targeting multiple signaling pathways, including reducing inflammatory infiltration, oxidative stress, inhibiting alternate macrophage activation, suppressing hepatic stellate cell activation, and reducing worm egg load. Natural products improve liver fibrosis associated with schistosomiasis, but further research is needed to elucidate the effectiveness of natural products in treating liver fibrosis caused by schistosomiasis, as there is no reported data from clinical trials in the literature., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Liu, Fisher, Pronyuk, Musabaev, Thu Hien, Dang and Zhao.)

Lepidium meyenii Walp. (Brassicaceae), also known as Maca or Peruvian ginseng, is a common ingredient in food supplements with many claimed health benefits, such as improved endurance, increased energy level, and enhanced sexual properties. Due to potential toxicity of its chemicals, including alkaloids, some regulatory authorities, e.g., in Belgium, Germany, the United States, expressed concerns about the safe consumption of Maca root. However, due to the lack of commercial standards, no established analytical method currently exists for this purpose. The current project focuses on the quantitative determination of potentially toxic alkaloids from Maca. The current study presents the first analytical method for quality control of alkaloid content in Maca-containing food and dietary supplements, assessing the presence of 11 major compounds belonging to three different classes, i.e., imidazole, β-carboline, and pyrrole alkaloids. An accurate, rapid, and sensitive UPLC-TQD-MS/MS method is reported, which was fully validated according to the International Council for Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) and SANTE/11312/2021 guidelines. To ensure the method's applicability and practicability in the absence of primary standards, validation of secondary standards (SSs) alongside primary standards (PSs) was also conducted for imidazole alkaloids. As a result, in Maca raw powder, total alkaloid content was found to vary from 418 to 554 ppm (mg/kg). Furthermore, all quantified imidazole alkaloids were ascertained to be the major alkaloids with the total content from 323 to 470 ppm in Maca raw powder, followed by the β-carboline and pyrrole alkaloids. It was also observed that the commercial preparation of finished products affects the total alkaloid content, evidenced by the large variation from 56 to 598 ppm. Ultimately, from a regulatory point of view, it seems advisible not to request the complete absence of the alkaloids but to impose a maximum level based on safety considerations. In addition to the analytical method, a low-cost, simple, and scalable synthetic scheme of macapyrrolins A, C, and G was reported for the first time., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

One new labdane- type diterpenoid, 3 β ,15-dihydroxylabda-8(17),12 E -dien-16,15-olide ( 1 ) named curcumatin and twelve known compounds, coronarin D ( 2 ), isocoronarin D ( 3 ), ( E )-labda-8(17),12-diene-15,16-dial ( 4 ), zerumin A ( 5 ), ( E )-labda-8(17),12-dien-15,16-dioic acid ( 6 ), furanodiene ( 7 ), linderazulene ( 8 ), zedoarol ( 9 ), zedoarondiol ( 10 ), germacrone-1,10-epoxide ( 11 ), germacrone-4,5-epoxide ( 12 ), and zingiberenol ( 13 ) were isolated from the ethanol extract of the roots of Curcuma aromatica Salisb. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis, HR-ESI-MS, and comparing with the NMR data reported in the literature. Compounds 2 , 5 , and 13 significantly inhibited the nitric oxide production effect in LPS-stimulated RAW 264.7 macrophages with IC 50 values of 8.8 ± 1.7, 4.0 ± 0.9, and 6.2 ± 0.4 µM, respectively.

In this study, Er-doped CoAl 2 O 4 nanocrystals (NCs) were synthesized via co-precipitation. All the NCs were crystallized in the form of a single phase with a spinel structure and Er 3+ ions replaced Al 3+ ions in the formation of the CoAl 2- x Er x O 4 alloy structure. The optical characteristics of the Er 3+ ion-doped CoAl 2 O 4 NCs were thoroughly investigated by analyzing both the UV-VIS and photoluminescence spectra, using the Judd-Ofelt theory. The effect of Er doping content on the luminescent properties of the CoAl 2 O 4 pigment (using lasers emitting at wavelengths of 413 and 978 nm) has been studied. The values of Judd-Oflet intensity parameters ( Ω 2 , Ω 4 , and Ω 6 ) were determined from the absorption spectra using the least square fitting method. The J-O parameters were calculated and compared with those of other host materials; the values of the Ω 2 , Ω 4 , and Ω 6 parameters decreased with an increase in Er concentration. This suggests that the rigidity and local symmetry of the host materials become weaker as the concentration of Er 3+ ions increases. The highest value of the Ω 2 parameter, when compared with Ω 4 and Ω 6 , suggests that the vibrational frequencies in the given samples are relatively low. The upconversion fluorescence phenomenon was observed and explained in detail under an excitation wavelength of 978 nm when the excitation power was varied., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background: In Vietnam, there has been no survey conducted on the prescribing and monitoring practices of oral anticoagulants to ensure that patients with atrial fibrillation receive appropriate. Objective: Therefore, we conducted this research to clarify the aforementioned issue in our hospital., Methods: We carried out a cross-sectional study by reviewing outpatient electronic medical records at the University Medical Center in Ho Chi Minh City. Our study included 1087 patients aged 18 years or older diagnosed with non-valvular atrial fibrillation (NVAF), who visited the Cardiology clinic between January 1st, 2021, and June 30th, 2021., Results: Among the 1087 patients with non-valvular atrial fibrillation (NVAF), 1036 were eligible for anticoagulant therapy. However, only 847 (81.8%) received prescriptions for either Vitamin K antagonists (VKAs) (n=129, 15.2%) or Non-Vitamin K antagonist oral anticoagulants (NOACs) (n=718, 84.8%). NOAC prescriptions were more commonly found in patients aged 75 or older (adjusted odds ratio [OR]=2), those with health insurance coverage (adjusted OR=2.9), and in individuals with a history of hypertension (adjusted OR=2). On the contrary, patients with a farming occupation were less likely to be prescribed NOACs (adjusted OR=0.4). About 75% of patients adhered to the guidelines recommending close monitoring during anticoagulant treatment. Notably, inappropriate prescriptions were identified in 27.7% of cases, especially among those with no recorded body weight (which is necessary for precise dosing based on creatinine clearance), those without health insurance, those with undocumented CHA2DS2-VASc scores, or those who were concurrently using antiplatelet agents., Conclusion: A discrepancy persists between clinical guidelines and the actual practice in diagnosing and managing patients with non-valvular atrial fibrillation (NVAF). It is crucial to prioritize the regular reevaluation of thromboembolic risk scores at follow-up appointments, ensure strict adherence to clinical monitoring standards, and align anticoagulant medication prescriptions with established guidelines., Competing Interests: The authors declare no conflicts of interest., (© 2024 Bui The Dung, Nguyen Thanh Hien, Tran Hoa, Cao Ngoc Mai Han.)

In this study, CdTe x Se 1- x (0 ≤ x ≤ 1) and CdTeSe:Gd y % ( y = 0-8.05) alloy semiconductor nanocrystals (NCs) were prepared by wet chemical method. The presence and composition of the elements in the sample were determined by energy dispersive X-ray (EDX) spectroscopy and X-ray photoelectron spectroscopy (XPS). Structural analysis of X-ray diffraction (XRD) patterns indicated that most NCs crystallized in the zinc blende (ZB) structure however some Gd-doped NCs ( y = 4.52 and 8.05%) crystallized in the wurtzite (WZ) structure. The emission peak of CdTe x Se 1- x (0 ≤ x ≤ 1) NCs varied over a wide range when changing x while the particle size remained almost unchanged. The effect of Gd doping on the structure and optical and magnetic properties of CdTeSe NCs was studied in detail. When the Gd concentration increases from 0-8.05%: (i) the structure of CdTeSe NCs gradually changed from ZB to WZ, (ii) the emission efficiency of the material was significantly reduced, (iii) the PL lifetime of samples increased more than 10 times, and (iv) the ferromagnetic properties of the material were enhanced. The research findings demonstrated that it is possible to control the crystal structure, optical characteristics, and magnetic properties of Gd-doped CdTeSe nanocrystals by adjusting the dopant concentration and chemical composition of the host material., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

After conducting an in silico analysis of the cryptic mdk cluster region and performing transcriptomic studies, an integrative Streptomyces BAC Vector containing the mdk gene sequence was constructed. The heterologous expression of the mdk cluster in Streptomyces albus J1074 resulted in the production of the angucyclic product, seongomycin, which allowed for the assesment of its antibacterial, antiproliferative, and antiviral activities. Heterologous production was further confirmed by targeted knock-out experiments involving key regulators of the biosynthetic pathways. We were further able to revise the core structure of maduralactomycin A, using a computational approach., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objective: Human respiratory syncytial virus (RSV) is a primary cause of paediatric severe acute respiratory infection (SARI) worldwide, especially in developing countries. We investigated the genetic characteristics of RSV in northern Viet Nam to determine the prevalence and distribution of subtypes as well as the diversity and transmission patterns of genotypes., Methods: In two facilities, from January 2017 to December 2020, 1563 clinical specimens were collected from paediatric patients hospitalized with SARI and tested for RSV. Selected positive samples underwent sequencing analysis targeting the second hypervariable region of the G gene using next-generation sequencing., Results: The RSV positivity rate was 28.02% (438/1563 samples), and prevalence was highest in children aged < 1 year (43.84%; 192/438). Subtype RSV-A accounted for 53.42% (234/438) of cases, RSV-B for 45.89% (201/438), and there was coinfection in 0.68% (3/438). Both subtypes cocirculated and peaked during August-September in each year of the study. Phylogenetic analysis showed that RSV-A samples belonged to the ON1 genotype, which has three subgenotypes: ON1.1, ON1.2 and ON1.3. However, we did not find the 72-nucleotide duplication in the second hypervariable region of the G gene, a characteristic of genotype ON1, in any RSV-A samples. RSV-B samples belonged to genotype BA9., Discussion: Our results provide additional molecular characterization of RSV infections in Viet Nam. Specially, our study is the first to report the absence of the 72-nucleotide duplication in the G gene of RSV-A genotype ON1 in Viet Nam, which may help in understanding the genetic evolution of RSV and be useful for vaccine development in the future., Competing Interests: The authors have no conflicts of interest to declare., ((c) 2023 The authors; licensee World Health Organization.)

In this study, Er 3+ doped ZnO semiconductor quantum dots (QDs) were synthesized using a wet chemical method. The successful doping of Er 3+ ions into the ZnO host lattice and the elemental composition was confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The ZnO and Er 3+ doped ZnO QDs with a hexagonal structure, spherical shape, and particle size of approximately 5 nm were revealed by XRD and transmission electron microscopy (TEM). The absorption, luminescence properties, and fluorescence lifetimes of the samples were studied as the concentration of Er 3+ ions varied. The intensity parameters, emission transition probabilities, branching ratios, and emission lifetimes of the excited levels of Er 3+ ions in the ZnO host were determined using the Judd-Ofelt theory, which provided insight into the covalent relationship between the ions and ligands as well as the nature of the ZnO host lattice. Moreover, the energy transfer process from the ZnO host to Er 3+ ions and the yield of this process are explained in detail along with specific calculations. The Er 3+ doped ZnO QDs displayed a significantly longer lifetime than undoped ZnO, which opens up many potential applications in fields such as photocatalysis, optoelectronics, photovoltaics, and biosensing., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Recently, there have been publications on preparing hybrid materials between noble metal and semiconductor for applications in surface-enhanced Raman scattering (SERS) substrates to detect some toxic organic dyes. However, the use of cuprous oxide/silver (Cu 2 O/Ag) to measure the trace amounts of methyl orange (MO) has not been reported. Therefore, in this study, the trace level of MO in water solvent was determined using a SERS substrate based on Cu 2 O microcubes combined with silver nanoparticles (Ag NPs). Herein, a series of Cu 2 O/Ag x ( x = 1-5) hybrids with various Ag amounts was synthesized via a solvothermal method followed by a reduction process, and their SERS performance was studied in detail. X-ray diffraction (XRD) and scanning electron microscopy results confirmed that 10 nm Ag NPs were well dispersed on 200-500 nm Cu 2 O microcubes to form Cu 2 O/Ag heterojunctions. Using the as-prepared Cu 2 O and Cu 2 O/Ag x as MO probe, the Cu 2 O/Ag5 nanocomposite showed the highest SERS activity of all samples with the limit of detection as low to 1 nM and the enhancement factor as high as 4 × 10 8 . The logarithm of the SERS peak intensity at 1389 cm -1 increased linearly with the logarithm of the concentration of MO in the range from 1 nM to 0.1 mM., Competing Interests: The authors declare no competing interests., (© 2023 The Authors.)

The Amaryllidaceae species are well-known as a rich source of bioactive compounds in nature. Although Hymenocallis littoralis has been studied for decades, its polar components were rarely explored. The current phytochemical investigation of Amaryllidaceae alkaloids from H. littoralis led to the identification of three previously undescribed compounds: O -demethyl-norlycoramine ( 1 ), (-)-2- epi -pseudolycorine ( 2 ) and (+)-2- epi -pseudolycorine ( 3 ), together with eight known compounds: 6α-hydroxyhippeastidine ( 4 ), 6β-hydroxyhippeastidine ( 5 ), lycorine ( 6 ), 2- epi -lycorine ( 7 ), zephyranthine ( 8 ), ungeremine ( 9 ), pancratistatin ( 10 ) and 9- O -demethyl-7- O -methyllycorenine ( 11 ). Among the eight previously reported compounds, five were isolated from H. littoralis for the first time (compounds 4 , 5 , 7 , 8, and 9 ). Compounds 1 , 4 , 5 , 7 , 8 , and 11 exhibited weak anti-SARS-CoV-2 activity (EC 50 = 40-77 µM) at non-cytotoxic concentrations. Assessment of cytotoxicity on the Vero-E6 cell line revealed lycorine and pancratistatin as cytotoxic substances with CC 50 values of 1.2 µM and 0.13 µM, respectively. The preliminary structure-activity relationship for the lycorine-type alkaloids in this study was further investigated, and as a result ring C appears to play a crucial role in their anti-SARS-CoV-2 activity.

Structural elucidation has always been challenging, and misassignment remains a stringent issue in the field of natural products. The growing interest in discovering unknown, complex natural structures accompanies the increasing awareness concerning misassignments in the community. The combination of various spectroscopic methods with molecular modeling has gained popularity in recent years. In this work, we demonstrated, for the first time, its power to fully elucidate the 2-dimensional and 3-dimensional structures of two epimers in an epimeric mixture of 6-hydroxyhippeastidine. DFT calculation of chemical shifts was first performed to assist the assignment of planar structures. Furthermore, relative and absolute configurations were established by three different ways of computer-assisted structure elucidation (CASE) coupled with ORD/ECD/VCD spectroscopies. In addition, the significant added value of OR/ORD computations to relative and absolute configuration determination was also revealed. Remarkably, the differentiation of two enantiomeric scaffolds (crinine and haemanthamine) was accomplished via OR/ORD calculations with cross-validation by ECD and VCD.

Background: Dysphagia is considered an important issue in managing and treating acute stroke, but there are currently no studies investigating this issue, especially for patients with acute ischemic stroke in Vietnam. Thus, we conducted this study to determine the prevalence of dysphagia and associated factors of dysphagia in patients with acute ischemic stroke in Vietnam., Materials and Methods: From June 2020 to January 2022, a cross-sectional study of patients with acute ischemic stroke was conducted in a tertiary hospital in Vietnam. The dysphagia was evaluated through a bedside screening test using the Gugging Swallowing Screen (GUSS). Factors associated with dysphagia were analysed using univariate and multivariate logistic regression., Results: The prevalence of dysphagia in patients with acute ischemic stroke was 71.6%, in which the mild, moderate and severe dysphagia accounted for 37.5%, 12.4% and 21.7%, respectively. Dysphagia significantly associated with age group 50-59 (OR = 2.2, 95% CI: 1.2-4.2), age group 60-69 (OR = 1.9, 95% CI: 1.04-3.4), age group >70 (OR = 2.2, 95% CI: 1.2-4.2), brainstem (OR = 4.0, 95% CI: 2.1-7.4), having communication disorder (OR = 1.5, 95% CI: 1.1-7.4) and having facial paralysis (OR = 17.9, 95% CI: 12.0-26.8)., Conclusion: Our study showed that the prevalence of dysphagia is high among patients with acute ischemic stroke in Vietnam. Intervention solutions should focus more on patient groups of higher age group, brainstem stroke, communication disorder and facial paralysis., Competing Interests: The authors declare that they have no competing interests., (© 2022 The Authors.)

Background: The w Mel strain of Wolbachia has been successfully introduced into Aedes aegypti mosquitoes and subsequently shown to reduce transmission of dengue and other pathogens, under both laboratory and field conditions. Here we describe the entomological outcomes of w Mel Wolbachia mosquito releases in two small communities in Nha Trang City in central Vietnam. Methods: The w Mel strain of Wolbachia was backcrossed into local Aedes aegypti genotype and mosquito releases were undertaken by community members or by staff. Field monitoring was undertaken to track Wolbachia establishment in local Ae. aegypti mosquito populations. Ecological studies were undertaken to assess relationships between environmental factors and the spatial and temporal variability in Wolbachia infection prevalence in mosquitoes. Results: Releases of w Mel Wolbachia Ae. aegypti mosquitoes in two small communities in Nha Trang City resulted in the initial establishment of Wolbachia in the local Ae. aegypti mosquito populations, followed by seasonal fluctuations in Wolbachia prevalence. There was significant small-scale spatial heterogeneity in Wolbachia infection prevalence in the Tri Nguyen Village site, resulting in the loss of w Mel Wolbachia infection in mosquitoes in north and center areas, despite Wolbachia prevalence remaining high in mosquitoes in the south area. In the second site, Vinh Luong Ward, Wolbachia has persisted at a high level in mosquitoes throughout this site despite similar seasonal fluctuations in w Mel Wolbachia prevalence. Conclusion: Seasonal variation in Wolbachia infection prevalence in mosquitoes was associated with elevated temperature conditions, and was possibly due to imperfect maternal transmission of Wolbachia . Heterogeneity in Wolbachia infection prevalence was found throughout one site, and indicates additional factors may influence Wolbachia establishment., Competing Interests: No competing interests were disclosed., (Copyright: © 2022 Hien NT et al.)

Objectives: To investigate the feasibility of establishing hospital-based antimicrobial stewardship (AMS) programmes comprising action-planning, educational interventions and data feedback in two provincial-level hospitals in Viet Nam., Design and Setting: This was an implementation research using participatory action process and existing resources from the Duke Antimicrobial Stewardship Outreach Network with local adjustments. A national stakeholder meeting and Strengths-Weaknesses-Opportunities-Threats (SWOT) analysis were conducted to identify gaps and potential interventions., Participants: Hospital AMS staff implemented activities throughout the study phases. Routinely collected patient data were analysed to support planning, implementation and evaluation., Interventions: Hospitals were considered as a complex adaptive system and leveraged their unique characteristics and interconnections to develop 1-year plans containing core interventions (data use, educational training, prospective audit with feedback (PAF) and evaluations)., Outcome Measures: We assessed feasibility using outputs from stakeholder meeting, SWOT analysis, baseline data, planning process and implementation., Results: The stakeholder meeting identified three gaps for AMS at national level: supportive policies, AMS training and core competencies and collaboration. At the hospitals, AMS programmes took 1 year for planning due to lack of hospital-specific procedures and relevant staff competencies. Baseline data (January-December 2019) showed variations in antibiotic consumption: 951 days of therapy (DOT) per 1000 days present in the control and 496 in the intervention wards in hospital 1, and 737 and 714 in hospital 2, respectively. During 1-year implementation, clinical pharmacists audited 1890 antibiotic prescriptions in hospital 1 (June 2020-May 2021) and 1628 in hospital 2 (July 2020-July 2021), and will continue PAF in their daily work., Conclusion: Our data confirmed the need to contextualise AMS programmes in low-income and middle-income countries (LMICs) and demonstrated the usefulness of implementation research design in assessing programme feasibility. Developing staff competencies, using local data to stimulate actions and integrating programme activities in routine hospital work are key to success in LMICs., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ.)

Background: The w Mel strain of Wolbachia has been successfully introduced into Aedes aegypti mosquitoes and subsequently shown to reduce transmission of dengue and other pathogens, under both laboratory and field conditions. Here we describe the entomological outcomes of w Mel Wolbachia mosquito releases in two small communities in Nha Trang City in central Vietnam. Methods: The w Mel strain of Wolbachia was backcrossed into local Aedes aegypti genotype and mosquito releases were undertaken by community members or by staff. Field monitoring was undertaken to track Wolbachia establishment in local Ae. aegypti mosquito populations. Ecological studies were undertaken to assess relationships between environmental factors and the spatial and temporal variability in Wolbachia infection prevalence in mosquitoes. Results: Releases of w Mel Wolbachia Ae. aegypti mosquitoes in two small communities in Nha Trang City resulted in the initial establishment of Wolbachia in the local Ae. aegypti mosquito populations, followed by seasonal fluctuations in Wolbachia prevalence. There was significant small-scale spatial heterogeneity in Wolbachia infection prevalence in the Tri Nguyen Village site, resulting in the loss of w Mel Wolbachia infection in mosquitoes in north and center areas, despite Wolbachia prevalence remaining high in mosquitoes in the south area. In the second site, Vinh Luong Ward, Wolbachia has persisted at a high level in mosquitoes throughout this site despite similar seasonal fluctuations in w Mel Wolbachia prevalence. Conclusion: Seasonal variation in Wolbachia infection prevalence in mosquitoes was associated with elevated temperature conditions, and was possibly due to imperfect maternal transmission of Wolbachia . Heterogeneity in Wolbachia infection prevalence was found throughout one site, and indicates additional factors may influence Wolbachia establishment., Competing Interests: No competing interests were disclosed., (Copyright: © 2021 Hien NT et al.)

Chemical investigation of the leaves and stems of Dioscorea bulbifera resulted in isolation of 10 compounds, including three new norclerodane diterpenoids, diosbulbiferins A (1) and B (2) and diosbulbiferinoside A (3), and one new natural congener, diosbulbiferin C (4), along with one new tetrahydrophenanthrene, diosbulbinone (8). Their structures were elucidated by comprehensive analyses of spectroscopic methods, including NMR and mass spectra. The absolute configurations of compounds 1-3 and 8 were deduced by time-dependent density functional theory (TD-DFT) electronic circular dichroism (ECD) spectroscopic analyses. In addition, cytotoxic effects against MCF-7, HepG2, and SK-Mel-2 cancer cells and in vitro anti-inflammatory effects of the isolated compounds in LPS-stimulated BV2 microglial cells were also reported., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Tb3+-Doped ZnSe quantum dots (QDs) with a Tb content in the range of 0.5-7% were successfully synthesized by a wet chemical method. X-Ray diffraction (XRD) and transmission electron microscopy (TEM) analyses revealed that the as-synthesized QDs had a zinc blende (ZB) structure with a particle size of approximately 4 nm. The effect of Tb-doping on the structure and optical properties of the ZnSe QDs was studied. The emission spectra and photoluminescence (PL) decay kinetics data confirmed the successful incorporation of Tb3+ ions into the ZnSe host. The PL spectra also revealed that the intensity of dopant emission was significantly enhanced owing to the energy transfer (ET) from the host emission. The efficiency of the ET process from the ZnSe host to Tb3+ ions and between Tb3+ ions and the nature of these interaction mechanisms were determined by applying the Inokuti-Hirayama and Reisfeld models. The features of the ligand field and the optical properties of Tb3+ ions in the ZnSe QDs were studied using Judd-Ofelt theory. The dependence of the chromaticity features of ZnSe:Tb3+ QDs on the Tb concentration was estimated by the chromaticity coordinates and correlated color temperature (CCT). The Tb3+-doped ZnSe QDs with visible, tunable, and very long lifetime emission have potential for practical applications such as biological labeling, photocatalysis, and white-LED devices.

Background: In response to the spread of the coronavirus disease 2019 (COVID-19), plenty of control measures were proposed. To assess the impact of current control measures on the number of new case indices 14 countries with the highest confirmed cases, highest mortality rate, and having a close relationship with the outbreak's origin; were selected and analyzed., Methods: In the study, we analyzed the impact of five control measures, including centralized isolation of all confirmed cases, closure of schools, closure of public areas, closure of cities, and closure of borders of the 14 targeted countries according to their timing; by comparing its absolute effect average, its absolute effect cumulative, and its relative effect average., Results: Our analysis determined that early centralized isolation of all confirmed cases was represented as a core intervention in significantly disrupting the pandemic's spread. This strategy helped in successfully controlling the early stage of the outbreak when the total number of cases were under 100, without the requirement of the closure of cities and public areas, which would impose a negative impact on the society and its economy. However, when the number of cases increased with the apparition of new clusters, coordination between centralized isolation and non-pharmaceutical interventions facilitated control of the crisis efficiently., Conclusion: Early centralized isolation of all confirmed cases should be implemented at the time of the first detected infectious case., Competing Interests: The authors have declared that no competing interests exist.

Objectives: To evaluate plombage surgery for hemoptysis control in pulmonary aspergilloma in high-risk patients., Methods: This study was carried out on 75 pulmonary aspergilloma patients presenting with hemoptysis that underwent a plombage surgery for approximately 7 years (November 2011-September 2018) at Pham Ngoc Thach Hospital. They revisited the hospital 6 months after plombage surgery and considered plombage removal. The group whose plombage was removed was compared with that whose plombage was retained 6 and 24 months after surgery., Results: Hemoptysis reduced significantly after surgery. Hemoptysis ceased in 91.67% of the patients and diminished in 8.33% of the patients 6 months after surgery. Similarly, hemoptysis ceased in 87.32% of the patients and diminished in 12.68% of the patients 24 months after surgery. Body mass index (BMI) index, Karnofsky score, and forced expiratory volume in one second (FEV1) increased. Plombage surgery was performed with operative time of 129.5 ± 36.6 min, blood loss during operation of 250.7 ± 163.1 mL, and the number of table tennis balls of 4.22 ± 2.02. No deaths related to plombage surgery were recorded. Plombage was removed in 29 cases because of patients' requirements (89.8%), infection (6.8%), and pain (3.4%). There were no patient developing complications after the treatment and there were no statistically significant differences between the two groups., Conclusions: Plombage surgery is safe and effective for hemoptysis control in pulmonary aspergilloma. To minimize the risk of long-term complications, surgeons should remove the plombage 6 months after the initial operation.

The role of samarium (Sm) dopant on the structural, morphological, and optical properties of CdS QDs and CdS/ZnS core/shell QDs was methodically reported. The synthesis of Sm-doped CdS QDs and CdS/ZnS QDs was carried out via a facile wet chemical method. The structure, chemical composition, and optical properties of the synthesized QDs were investigated by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy (RS), and photoluminescence (PL) spectroscopy. XRD analysis showed that the synthesized CdS QDs exhibited zinc blende structure which was not affected by doping Sm 3+ ions. The particle size of the CdS:Sm and CdS:Sm (2%)/ZnS QDs was estimated to be ∼4 nm and ∼7 nm, respectively. Transmission electron microscopy (TEM) images revealed that the incorporation of Sm dopant did not significantly affect the size and morphology of CdS QDs, while the formation of the ZnS shell increased the particle size. XPS and XRD results confirmed the successful incorporation of Sm 3+ ions into the CdS QDs. The effect of dopant concentration on the structural and luminescent properties was studied. The emission and excitation spectra of Sm 3+ -doped CdS QDs and CdS/ZnS QDs consisted of the characteristic lines corresponding to the intra-configurational f-f transitions. The energy transfer (ET) mechanism from the host to Sm 3+ ions and the ET process through cross-relaxation between Sm 3+ ions have been elucidated. The effect of the ZnS shell on the optical stability of the Sm 3+ -doped CdS QDs was studied in detail and the results showed that the CdS:Sm (2%)/ZnS QDs retained their good emission characteristics after 376 days of fabrication. The luminescent properties of Sm-doped QDs ranging from violet to red and PL lifetime extending to milliseconds demonstrated that these QDs are the potential materials for applications in white LEDs, biomarkers, and photocatalysis., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Vietnam has been conducting HIV/sexually transmitted infection (STI) integrated bio-behavioral surveillance surveys on men who have sex with men (MSM) as well as other key populations since 2005. Although HIV prevalence in the Vietnamese general population remains below 1%, it is expected to be much higher among MSM.Data on HIV prevalence and sexual and drug use behaviors were collected from MSM in Ho Chi Minh City (HCMC) in 2006 (n = 397), 2009 (n = 399) and 2013 (n = 350) using respondent-driven sampling. Eligible participants were males, aged ≥15 years who reported having manual, oral, or anal sexual activity with males in the past year and lived, worked or socialized in HCMC.HIV seroprevalence among MSM was 5.8% in 2006, 16.1% in 2009 and 12.1% in 2013 and prevalence of at least one STI (syphilis, gonorrhea and/or chlamydia infection) was 11.4% in 2006 and 15.6% in 2009 (no data for 2013). Significant, but small, increasing trends were found for MSM who reported ever testing and receiving results for HIV and for HIV prevalence. No significant changes for condom use, injecting and non-injecting drug use, or and receipt of free condoms were observed.Although a small percentage of MSM reported injecting drugs, HIV was positively associated with ever injecting drugs. Programs targeting MSM should include screening and treatment for injection drug use to most effectively control the HIV/AIDS epidemic among MSM in HCMC.

Tunable copper doped Zn 1- x Cd x S alloy quantum dots (QDs) were successfully synthesized by the wet chemical method. A one-step method is developed to synthesize doped ternary QDs which is more preferable than a two-step method. The influence of experimental parameters like the Zn/Cd ratio and Cu dopant concentration has been investigated using various spectroscopic techniques like UV-visible, photoluminescence, X-ray diffraction and Raman spectroscopy. The absorption and emission properties can be tuned by changing the concentration of components of the ternary QDs. The high concentration of dopant completely quenched the emission of the ternary QDs. EDX gives confirmation of the elemental composition of the synthesized samples. The obtained results suggest the successful doping of the ternary QDs. Interestingly, the study results revealed that the crystal structure (ZB and/or WZ) and the dual emission of the Cu-doped Zn 1- x Cd x Se alloy QDs could be controlled by varying the dopant concentration and chemical composition of the host. Doping also leads to enhancement in emission properties and provides more stability to ternary QDs. The enhancement in the photoluminescence (PL) decay lifetime of Cu-doped ternary QDs can be advantageous for optoelectronic and biosensor applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)