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Rotavirus (RV) is the most common cause of severe childhood diarrhea worldwide. Since 2006, the WHO has approved the use of two vaccines against Rotavirus (RotaTeq and Rotarix), which has contributed to a significant reduction in morbidity and mortality from this disease in children under 5 years of age. Beside of that, the presence of vaccines could also cause selective pressure among circulating RV strains. Diarrhea samples were a part of the study of the project “Evaluation of rotavirus vaccine effectiveness in Vietnam” and some diarrhea samples were randomly selected from 2010 - 2015 and were stored in our laboratory. Rotavirus antigen in diarrhea samples was detected using the Premier Rotaclone kit. G and P genotypes were determined by RT-PCR using type specific primers. The nucleotide sequencewas determined by next generation sequencing and phylogenetic analysis was performed by the neighbor-joining method. 375/1715 (21.9%) samples detected G3 strain include equine-like G3 (eG3) and human G3 (hG3). The prevalence of G3 strains decreased from 2016 to 2021. All eleven gene segments were typed among 34 samples and substantial diversity among the circulating strains was observed. The circulating G3 strains were also phylogenetically diverse and related to strains from several different countries, different origins such as human (20 samples), pig (1 sample), cat (3 samples) and equine (10 samples). Comparing with the vaccine strains, the antigenic epitopes present on VP7 ofG3 in Vietnam differed considerably, especially the K238N. With the genetic characteristics of the G3 strain, it could contribute to the vaccine effectiveness in Vietnam.

Rotavirus (RV), Norovirus (NV), Sapovirus (SaV) and Astrovirus (Ast) are the leading causes of gastroenteritis and mortality in children worldwide. RV vaccines help to reduce the burden of diarrhea while the importance of other viruses is increasing. Therefore, we conducted a cross-sectional descriptive study to determine prevalence of these viruses in hospitalized children under 5 years old in Nam Dinh province with approximately 80% of RV vaccine coverage. We randomly selected 579 (25%) among diarrheal samples collected in 4 district hospitals from Dec. 2017 to Nov. 2019. An ELISA kit was employed to detect RV and the multiplex real-time RT-PCR with specific primers to detect NV, SaV and Ast. These viruses were found among 64.3% of hospitalized children, of which NV and RV were present in 28.5% and 21.4%, respectively, while SaV and Ast were detected in 3.3% and 2.6%, respectively. Co-infections accounted for 8.5%, mainly among RV and 3 other viruses. There is a significant difference in RV and NV positive rates between vaccinated and unvaccinated groups (p < 0.001 and p = 0.008, respectively). This study contributed to the understanding of the potential impact of rotavirus vaccine on other diarheal pathogens and emphasize the need for further epidemiological studies when the nationwide RV vaccination in Vietnam is implementing.

BACKGROUND: Diarrhoeal disease is a leading cause of childhood illness and death globally, and Shigella is a major aetiological contributor for which a vaccine might soon be available. The primary objective of this study was to model the spatiotemporal variation in paediatric Shigella infection and map its predicted prevalence across low-income and middle-income countries (LMICs). METHODS: Individual participant data for Shigella positivity in stool samples were sourced from multiple LMIC-based studies of children aged 59 months or younger. Covariates included household-level and participant-level factors ascertained by study investigators and environmental and hydrometeorological variables extracted from various data products at georeferenced child locations. Multivariate models were fitted and prevalence predictions obtained by syndrome and age stratum. FINDINGS: 20 studies from 23 countries (including locations in Central America and South America, sub-Saharan Africa, and south and southeast Asia) contributed 66 563 sample results. Age, symptom status, and study design contributed most to model performance followed by temperature, wind speed, relative humidity, and soil moisture. Probability of Shigella infection exceeded 20% when both precipitation and soil moisture were above average and had a 43% peak in uncomplicated diarrhoea cases at 33°C temperatures, above which it decreased. Compared with unimproved sanitation, improved sanitation decreased the odds of Shigella infection by 19% (odds ratio [OR]=0·81 [95% CI 0·76-0·86]) and open defecation decreased them by 18% (OR=0·82 [0·76-0·88]). INTERPRETATION: The distribution of Shigella is more sensitive to climatological factors, such as temperature, than previously recognised. Conditions in much of sub-Saharan Africa are particularly propitious for Shigella transmission, although hotspots also occur in South America and Central America, the Ganges-Brahmaputra Delta, and the island of New Guinea. These findings can inform prioritisation of populations for future vaccine trials and campaigns. FUNDING: NASA, National Institutes of Health-The National Institute of Allergy and Infectious Diseases, and Bill & Melinda Gates Foundation. publishedVersion

Bài báo này trình bày nghiên cứu tích hợp công nghệ hybrid với năng lượng mặt trời vào phương tiện giao thông thủy nội địa cỡ nhỏ. Trong nghiên cứu này, dữ liệu khảo sát kết hợp với ý kiến chuyên gia được tổng hợp và phân tích nhằm đưa ra phương án thiết kế hình dáng và công nghệ hybrid ứng dụng năng lượng mặt trời phù hợp với đặc thù phương tiện giao thông thủy cỡ nhỏ. Các ràng buộc mớn nước, tĩnh không, tuyến luồng kênh rạch, bề rộng kênh rạch đều đảm bảo tính năng kỹ thuật theo nhiệm vụ thư thiết kế. Giải pháp thiết kế hệ thống hybrid ứng dụng năng lượng mặt trời gồm phần cứng và phần mềm phục vụ tích trữ, điều khiển và vận hành cũng đã được so sánh và đánh giá. Kết quả cho thấy tính khả thi của nghiên cứu tích hợp công nghệ hybrid ứng dụng năng lượng mặt trời vào các phương tiện giao thông cỡ nhỏ hoạt động ở vùng hồ, kênh rạch tại khu vực TP. HCM và Đồng Bằng Sông Cửu Long.

The antioxidative activity of natural product compound amurensin H (1) and its three synthetic compounds 5-(6-hydroxy-2-(4-hydroxyphenyl)benzofuran-3-yl)benzene-1,3-diol (2), (E)-2-(4-hydroxyphenyl)-4-(4-hydroxystyryl)benzofuran-6-ol (3), and (E)-5-(6-hydroxy-4-(4-hydroxystyryl)benzofuran-3-yl)benzene-1,3-diol (4) are extensively studied by DFT (density functional theory) method. At the theoretical B3LYP/6-311G(d,p) level, the HAT (hydrogen atom transfer) mechanism is assignable to compounds 1-4 in gas, but the SPL-ET (sequential proton loss-electron transfer) mechanism is the main way in water and methanol. The antioxidative actions of the studied compounds are mainly based on OH bond breakage, especially OH groups directly substituted at benzofuran nucleus. Amurensin H (1) is better than the remaining compounds due to 6-OH group. 1-6-OH induces the low bond BDE (bond dissociation enthalpy) and PA (proton affinity) values in thermal analysis. Importantly, the kinetic reaction of 1-6-OH + HOO• in methanol exerts the lowest ΔG# value of 5.6 kcal/mol and the highest K value of 1.983 x 1010 L/mol.s. At the B3LYP/6-311G(d,p)/LANL2DZ level, the successful formation of complex [Zn(compound 1)2(H2O)2] at 6-OH is confirmed by molecular orbital and UV-Vis spectroscopic analyses.

High-risk human papillomavirus (HPV) genotypes are the leading causes of anogenital cancer, including cervical cancer. Screening these genotypes will potentially alleviate the disease burden that HPV causes. Therefore, NIHERealtime PCR hrHPV was developed based on the principle of multiplex real-time PCR. The objective of this study is to establish the specifcations of this assay in detecting and identifying 14 high-risk genotypes of HPV. The specifcations of this assay including cross-reactivity, sensitivity and specifcity, the limit of detection and stability, were evaluated with clinical samples, HPV positive control code 06/202 and 06/206 (National Institute for Biological Standards and Control) and in-house plasmids. Four different real-time systems and two commercial assays were applied for comparison. No cross detection of bacteria and viruses related to other genital-anal was observed. The sensitivity and the specifcity of this kit both reached 100% for HPV-18, 92.3% and 100% for HPV-16, and ranged from 90.0% - 100% for the other 12 high-risk genotypes (n = 92) with the detection limit of 5 copies/µl for HPV-16 and HPV-18, and 10 copies/µl for the other 12 high-risk genotypes HPV. This test was stable for up to 12 months under -20oC condition. Equivalent performance was demonstrated on all four real-time systems. Finally, the product was highly comparable with the Sacace kit, Italy (HPV Genotypes 14 Real-™ Quant, V67-100FRT), evaluated by the World Health Organization. The NIHE kit has the potential to be used in the early detection of HPV infection to improve control, prevention and treatment of HPV-related anogenital diseases.

The objective of a cross sectional study is to describe the situation of human papillomavirus (HPV) infection and risk behaviours among 800 men who have sex with men (MSM) in Hanoi and Ho Chi Minh City (HCMC) from December 2017 to May 2018 using respondent - driven sampling method (RDS). The results showed that the prevalence of any type of HPV infection was 29.8% (33% in HCMC, 26.5% in Hanoi) and the prevalence of any high - risk type of HPV infection was 24.0% (29.0% in HCMC, 19.0% in Hanoi). The risk behaviours to HPV among MSM in both cities included: Alcohol use (69.9%), smoking (30.7%), drug use (8.5%), having frst sexual intercourse under 18 years old (31.8%), having group sex (10.5%), having sex with both men and women (21.7%). The factors which had statistically signifcant differences with HPV status in MSM group included: City, age group, and marital status. These results showed that there is a need for medical interventions for MSM to improve individual health as well as to minimize the transmission of HPV in this population.

BackgroundDiarrheal disease remains a leading cause of childhood illness and mortality and Shigella is a major etiological contributor for which a vaccine may soon be available. This study aimed to model the spatiotemporal variation in pediatric Shigella infection and map its predicted prevalence across low- and middle-income countries (LMICs).MethodsIndependent participant data on Shigella positivity in stool samples collected from children aged ≤59 months were sourced from multiple LMIC-based studies. Covariates included household- and subject-level factors ascertained by study investigators and environmental and hydrometeorological variables extracted from various data products at georeferenced child locations. Multivariate models were fitted, and prevalence predictions obtained by syndrome and age stratum.Findings20 studies from 23 countries contributed 66,563 sample results. Age, symptom status, and study design contributed most to model performance followed by temperature, wind speed, relative humidity, and soil moisture. Shigella probability exceeded 20% when both precipitation and soil moisture were above average and had a 43% peak in uncomplicated diarrhea cases at 33°C temperatures, above which it decreased. Improved sanitation and open defecation decreased Shigella odds by 19% and 18% respectively compared to unimproved sanitation.InterpretationThe distribution of Shigella is more sensitive to climatological factors like temperature than previously recognized. Conditions in much of sub-Saharan Africa are particularly propitious for Shigella transmission, though hotspots also occur in South and Central America, the Ganges–Brahmaputra Delta, and New Guinea. These findings can inform prioritization of populations for future vaccine trials and campaigns.FundingNASA 16-GEO16-0047; NIH-NIAID 1R03AI151564-01; BMGF OPP1066146.

The molecular properties of apigenin, luteolin and nevadensin which are three naturally flavonoid compounds have been studied theoretically by DFT method at 6-311++G(d,p) level. Both FMO analysis, mechanism, and kinetics studied suggested that compound Luteolin (compound 3) was a promising antioxidant agent. The results indicated that HAT is thermodynamically preferred in the gas phase, and SPLET is the thermodynamically favorable pathway in methanol and water

The antioxidative activities of the original compound dehydro-δ-viniferin (1) and its three designated derivatives, 5-(2-(4-hydroxyphenyl)benzofuran-3-yl)benzene-1,3-diol (2), (E)-5-(2-(2-(4-hydroxyphenyl)benzofuran-5-yl)vinyl)benzene-1,3-diol (3), and (E)-5-(2-(3-(3,5-dihydroxyphenyl)benzofuran-5-yl)vinyl)benzene-1,3-diol (4), are extensively studied, mainly based on density functional theory (DFT) calculations using the hybrid functional B3LYP and the 6-311G(d,p) basis set. The O–H bond breakage is reasonably responsible for the antioxidative activity, whereas the environment greatly influences results. In solvents, namely water, methanol, and especially acetone, the SPL–ET mechanism (sequential proton loss–electron transfer) is mainly likely to be a antioxidative route for four studied compounds; however, the HAT mechanism (hydrogen atom transfer) is assigned to these compounds in the gaseous phase. Benzofuran–stilbene hybrid compound 3 with a planar structure is the best antioxidative agent; its 4′-OH induced the lowest PA values in liquid solvents as well as the lowest BDE value in the gas solvent. The kinetic investigation of the interactions of compounds 1–4 with HOO˙ radicals evidently provides the lowest Gibbs activation energy ΔG# = 4.7 kcal mol−1 and the highest rate constant K = 5.702 × 1010 L mol−1 s−1, which again are assigned to 3-4′-OH. At the theoretical level of B3LYP/6-311G(d,p)/LANL2DZ, the complex [La(compound 3)3] in gas induces a redshift in the UV-Vis spectrum.

Quinolone and isoquinolone alkaloids, which were found in the plant kingdom, are now potential antioxidants. In this case study, a quantum calculated procedure utilizing the density functional theory (DFT)-B3LYP method coupled with basis set 6–311++G(d,p) was used to investigate free-radical quenching activity of alkaloidal quinolone viridicatol (1) and alkaloidal isoquinolone 5-hydroxy-8-methoxy-4-phenylisoquinolin-1(2H)-one (2). On the basis of thermodynamic perspective and from the findings, the powerful antioxidative potential of these two title compounds in the liquids water, methanol, and especially DMSO was mostly driven by the proton affinity (PA), consistent with the SPLET (sequential proton loss electron transfer) mechanism. The environmental effect has also been investigated, and the antioxidative action caused by O–H bond disruption is easier than that of N–H bond in both the gaseous phase and liquids. In the gaseous phase, the combinations of two studied compounds and •OOH/DPPH radicals are kinetic evidence, including two intermediates and one transition state. From thermodynamic and kinetic viewpoints, compound 2 can be seen as a therapeutically useful agent in antioxidative treatment because of the role of a 5-hydroxy group.

Structural, electronic, and optical properties of a series of organic semiconductors based on dithienosilole (DTS) and its derivatives were theoretically studied using density functional theory (DFT) and time-dependent-DFT (TD-DFT) methods. Our calculated results suggest that two phenyl groups substituted at silicon atom, as well as functional groups at 1,1′-positions, are an efficient way to induce substantial changes in the optical and electronic properties of DTS compounds. By substituting the functional groups at 1,1′-positions of DTS dimeric compound, we successfully make changes in the charge transport rate of the designed compounds, especially a remarkable reduction in hole reorganization energies. Introduction of pyridyl groups is efficient to lower the LUMO level, and optical band gap energies, to increase the charge and the balance transport rate between hole and electron for producing the ambipolar transport materials promising for use not only in the OLED but also in DSSC devices.

Stilbenoid-type 2-phenylbenzofuran derivatives, which are widely distributed in nature, are now promising antioxidant agents. In the present study, a quantum computational approach principally based on the DFT/B3LYP method with the 6-311++G(d,p) basis set was used to shed light on free radical scavenging for the isolated compounds stemofurans A-K and S-W. On the basis of the findings and from a thermodynamic perspective, the antioxidant activity of all studied compounds in the gaseous phase was mostly controlled by the O-H bond dissociation enthalpy (BDE), consistent with the hydrogen atom transfer (HAT) mechanism. The solvent effect was investigated, and the hydroxyl radicals of these studied compounds possessed the lowest proton affinity (PA) enthalpy and the sequential proton loss electron transfer (SPLET) pathway occurred in water, methanol and acetone. The studied compounds interacted with DPPH radicals, which is kinetic evidence of the involvement of two intermediates and one transition state. From both thermodynamics and kinetics perspectives, it can be proposed that stemofuran U is likely to be a leader compound in antioxidant drug development due to the presence of a 4'-OH moiety. Regarding the structure-bioactivity relationship, methylation can lead to a decrease in BDE.

Background The etiology of intussusception, the leading cause of bowel obstruction in infants, is unknown in most cases. Adenovirus has been associated with intussusception and slightly increased risk of intussusception with rotavirus vaccination has been found. We conducted a case-control study among children Methods From 2015 to 2017, we enrolled 1-to-1 matched intussusception cases and hospital controls; 249 pairs were included. Stool specimens were tested for 37 infectious agents using TaqMan Array technology. We used conditional logistic regression to estimate odds ratio (OR) and 95% confidence interval (CI) of each pathogen associated with intussusception in a pooled analysis and quantitative subanalyses. Results Adenovirus (OR, 2.67; 95% CI, 1.75–4.36) and human herpes virus 6 (OR, 3.50; 95% CI, 1.15–10.63) were detected more frequently in cases than controls. Adenovirus C detection Conclusions In this comprehensive evaluation, adenovirus and HHV-6 were associated with intussusception. Future research is needed to better understand mechanisms leading to intussusception, particularly after rotavirus vaccination.

Flavone and isoflavone derivatives have drawn much attention because of their antioxidant radical scavenging capacity. Based on computational methods, we now present the antioxidant potential results of flavone norartocarpetin (1) and isoflavone 2′-hydroxygenistein (2). The optimized structures of the neutral and radical forms have been carried out by DFT-B3LYP method with the 6-311++G (d,p) basis set. From the findings and thermodynamic point of view, ring B system of either flavone or isoflavone is considered as an active centre in facilitating antioxidant reactions. Antioxidant activities are mostly driven by the O–H bond dissociation enthalpy (BDE) following hydrogen atom transfer (HAT) mechanism. In all studied environments, the lowest BDE values are found in 4′-OH and 2′-OH of compounds 1-2, respectively. Isoflavone 2 possesses a higher antioxidant capacity than that of flavone 1. Of extensive analysis, intramolecular hydrogen bonds and solvents not only greatly influence on antioxidant aspect but also directly affect the structural properties, especially spectroscopic outcomes.

This article presents the results of the quantitative structure – activity relationship (QSAR) study of bisphenol A (BPA) and its analogs using quantum chemistry calculations and method of artificial neural networks (ANN). Molecular structural analysis is performed using Density Functional Theory (DFT) at the B3LYP/6-31+G(d) level. The quantum calculations focus on finding the optimized molecular structures, vibrational frequencies, the molecular orbital energies with reasonable accuracy. The study of electron density distribution was carried out in the framework of the natural bond orbital (NBO) methods. The obtained parameters and known observable estrogen activities are used as input data for constructing the QSAR model, using the artificial neural network method. Based on the artificial neural network method the quantum parameters having the strongest impact on the estrogen activity of the compounds were revealed. The internal and external validation methods have been performed to test the performance and the stability of the model. The statistical parameters obtained of the QSAR model were: R2 = 0.99; Q2LOO = 0.98; R2Predict = 0.98. According to the obtained results, our proposed model, constructing by method of artificial neural network using the parameters of quantum chemistry is adequate and may be useful to predict of estrogen activities for unexplored derivatives and BPA analogs with moderate reliability.