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1.
PLoS Biol ; 22(9): e3002834, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283942

RESUMO

Dengue virus (DENV) is currently causing epidemics of unprecedented scope in endemic settings and expanding to new geographical areas. It is therefore critical to track this virus using genomic surveillance. However, the complex patterns of viral genomic diversity make it challenging to use the existing genotype classification system. Here, we propose adding 2 sub-genotypic levels of virus classification, named major and minor lineages. These lineages have high thresholds for phylogenetic distance and clade size, rendering them stable between phylogenetic studies. We present an assignment tool to show that the proposed lineages are useful for regional, national, and subnational discussions of relevant DENV diversity. Moreover, the proposed lineages are robust to classification using partial genome sequences. We provide a standardized neutral descriptor of DENV diversity with which we can identify and track lineages of potential epidemiological and/or clinical importance. Information about our lineage system, including methods to assign lineages to sequence data and propose new lineages, can be found at: dengue-lineages.org.

2.
Am J Physiol Cell Physiol ; 326(3): C978-C989, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38314722

RESUMO

Sleep deprivation (SD) is widely acknowledged as a significant risk factor for cognitive impairment. In this study, intraperitoneal caffeine administration significantly ameliorated the learning and memory (L/M) deficits induced by SD and reduced aggressive behaviors in adult zebrafish. SD led to a reduction in protein kinase A (PKA) phosphorylation, phosphorylated-cAMP response element-binding protein (p-CREB), and c-Fos expression in zebrafish brain. Notably, these alterations were effectively reversed by caffeine. In addition, caffeine mitigated neuroinflammation induced by SD, as evident from suppression of the SD-mediated increase in glial fibrillary acidic protein (GFAP) and nuclear factor-κB (NF-κB) activation. Caffeine restored normal O-GlcNAcylation and O-GlcNAc transferase (OGT) levels while reversing the increased expression of O-GlcNAcase (OGA) in zebrafish brain after SD. Intriguingly, rolipram, a selective phosphodiesterase 4 (PDE4) inhibitor, effectively mitigated cognitive deficits, restored p-CREB and c-Fos levels, and attenuated the increase in GFAP in brain induced by SD. In addition, rolipram reversed the decrease in O-GlcNAcylation and OGT expression as well as elevation of OGA expression following SD. Treatment with H89, a PKA inhibitor, significantly impaired the L/M functions of zebrafish compared with the control group, inducing a decrease in O-GlcNAcylation and OGT expression and, conversely, an increase in OGA expression. The H89-induced changes in O-GlcNAc cycling and L/M dysfunction were effectively reversed by glucosamine treatment. H89 suppressed, whereas caffeine and rolipram promoted O-GlcNAc cycling in Neuro2a cells. Our collective findings underscore the interplay between PKA signaling and O-GlcNAc cycling in the regulation of cognitive function in the brain, offering potential therapeutic targets for cognitive deficits associated with SD.NEW & NOTEWORTHY Our observation highlights the intricate interplay between cAMP/PKA signaling and O-GlcNAc cycling, unveiling a novel mechanism that potentially governs the regulation of learning and memory functions. The dynamic interplay between these two pathways provides a novel and nuanced perspective on the molecular foundation of learning and memory regulation. These insights open avenues for the development of targeted interventions to treat conditions that impact cognitive function, including SD.


Assuntos
Disfunção Cognitiva , Isoquinolinas , Privação do Sono , Sulfonamidas , Animais , Privação do Sono/tratamento farmacológico , Peixe-Zebra/metabolismo , Cafeína/farmacologia , Rolipram , Acetilglucosamina/metabolismo , Processamento de Proteína Pós-Traducional , Cognição , Disfunção Cognitiva/tratamento farmacológico , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo
3.
AIDS Care ; 36(4): 553-560, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37909053

RESUMO

ABSTRACTIn resource-limited settings, alternatives to HIV viral load testing may be necessary to monitor the health of people living with HIV. We assessed the utility of self-report antiretroviral therapy (ART) to screen for HIV viral load among persons who inject drugs in Hai Phong Vietnam, and consider differences by recent methamphetamine use. From 2016 to 2018 we recruited PWID through cross sectional surveys and collected self-report ART adherence and HIV viral load to estimate sensitivity, specificity, positive and negative predictive values (PPV, NPV) and likelihood ratios (LR+, LR-) for self-reported ART adherence as a screening test for HIV viral load. We used three HIV viral load thresholds: < 1000, 500 and 250 copies/mL; laboratory-confirmed HIV viral load was the gold standard. Among 792 PWID recruited, PPV remained above 90% regardless of recent methamphetamine use with slightly higher PPV among those not reporting recent methamphetamine use. The results remained consistent across all three HIV viral load thresholds. Our findings suggest that when HIV viral load testing is not possible, self-reported ART adherence may inform decisions about how to prioritize HIV viral load testing among PWID. The high PPV values suggest self-reported high ART adherence indicates likely HIV viral suppression, irrespective of methamphetamine use.


Assuntos
Usuários de Drogas , Infecções por HIV , Metanfetamina , Abuso de Substâncias por Via Intravenosa , Humanos , Metanfetamina/uso terapêutico , Autorrelato , Abuso de Substâncias por Via Intravenosa/epidemiologia , Abuso de Substâncias por Via Intravenosa/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Vietnã/epidemiologia , Carga Viral , Estudos Transversais , Antirretrovirais/uso terapêutico , Adesão à Medicação
4.
Anal Bioanal Chem ; 416(7): 1613-1621, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38285228

RESUMO

Capillary electrophoresis (CE) is a powerful and sensitive tool for speciation analysis when combined with inductively coupled plasma mass spectrometry (ICP-MS); however, the performance of this technique can be limited by the nature of pneumatic nebulizers. This study compares two commercially available pneumatic nebulizers to a newly introduced vibrating capillary nebulizer (VCN) for on-line coupling of CE with ICP-MS. The VCN is a low-cost, non-pneumatic nebulizer that is based on the design of capillary vibrating sharp-edge spray ionization. As a piezoelectrically driven nebulization source, the VCN creates an aerosol independent of gas flows and does not produce a low-pressure region at the nebulizer orifice. To compare the systems, we performed replicate analyses of sulfate in river water with each nebulizer and the same CE and ICP-MS instruments and determined the figures of merit of each setup. With the CE-VCN-ICP-MS setup, we achieved around 2-4 times lower sensitivity compared to the commercial setups. However, the VCN-based setup provided lower noise levels and better linear correlation from the analysis of calibration standards, which resulted in indistinguishable LOD and LOQ values from the in-house-built VCN-based and commercial setups for CE-ICP-MS analysis. The VCN is found to have the highest baseline stability with a standard deviation of 3500 cts s-1, corresponding to an RSD of 2.7%. High reproducibility is found with the VCN with a peak area RSD of 4.1% between 3 replicate measurements.

5.
Antonie Van Leeuwenhoek ; 117(1): 39, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388985

RESUMO

Melioidosis, a human infectious disease with a high mortality rate in many tropical countries, is caused by the pathogen Burkholderia pseudomallei (B. pseudomallei). The function of the B. pseudomallei sigma S (RpoS) transcription factor in survival during the stationary growth phase and conditions of oxidative stress is well documented. Besides the rpoS, bioinformatics analysis of B. pseudomallei genome showed the existence of two rpoN genes, named rpoN1 and rpoN2. In this study, by using the mouse macrophage cell line RAW264.7 as a model of infection, the involvement of B. pseudomallei RpoS and RpoN2 in the invasion, intracellular survival leading to the reduction in multinucleated giant cell (MNGC) formation of RAW264.7 cell line were illustrated. We have demonstrated that the MNGC formation of RAW264.7 cell was dependent on a certain number of intracellular bacteria (at least 5 × 104). In addition, the same MNGC formation (15%) observed in RAW264.7 cells infected with either B. pseudomallei wild type with multiplicity of infection (MOI) 2 or RpoN2 mutant (∆rpoN2) with MOI 10 or RpoS mutant (∆rpoS) with MOI 100. The role of B. pseudomallei RpoS and RpoN2 in the regulation of type III secretion system on bipB-bipC gene expression was also illustrated in this study.


Assuntos
Proteínas de Bactérias , Burkholderia pseudomallei , Melioidose , Fator sigma , Animais , Humanos , Camundongos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Burkholderia pseudomallei/genética , Burkholderia pseudomallei/metabolismo , Linhagem Celular , Células Gigantes/metabolismo , Células Gigantes/microbiologia , Macrófagos/metabolismo , Melioidose/microbiologia , Fator sigma/metabolismo
6.
Biosci Biotechnol Biochem ; 88(10): 1127-1135, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38964835

RESUMO

Seven new oleanane-type triterpene saponins, lysimaponins A-G, were isolated from aerial parts of Lysimachia laxa Baudo. Their chemical structures have been elucidated by analysis of spectroscopic and chemical methods. All compounds were evaluated for their antibacterial effects against Microcystis aeruginosa, Vibrio parahaemolyticus, V. harveyi, V. vulinificus, V. cholerae, and V. alginolyticus. All compounds showed potent antibacterial activities against the cyanobacteria M. aeruginosa with IC50 values ranging from 14.4 ± 1.2 to 35.3 ± 2.2 µg/mL. Compounds 1, 2, 4-7 inhibited V. parahaemolyticus with MIC values ranging from 64 to 256 µg/mL. The results suggested that saponins from L. laxa could be potential anti-cyanobacteria agents.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Ácido Oleanólico , Primulaceae , Saponinas , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Saponinas/farmacologia , Saponinas/química , Saponinas/isolamento & purificação , Primulaceae/química , Ácido Oleanólico/farmacologia , Ácido Oleanólico/química , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/isolamento & purificação , Microcystis/química , Lysimachia
7.
J Med Internet Res ; 26: e45070, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498020

RESUMO

BACKGROUND: The electronic National Immunization Information System (NIIS) was introduced nationwide in Vietnam in 2017. Health workers were expected to use the NIIS alongside the legacy paper-based system. Starting in 2018, Hanoi and Son La provinces transitioned to paperless reporting. Interventions to support this transition included data guidelines and training, internet-based data review meetings, and additional supportive supervision visits. OBJECTIVE: This study aims to assess (1) changes in NIIS data quality and use, (2) changes in immunization program outcomes, and (3) the economic costs of using the NIIS versus the traditional paper system. METHODS: This mixed methods study took place in Hanoi and Son La provinces. It aimed to analyses pre- and postintervention data from various sources including the NIIS; household and health facility surveys; and interviews to measure NIIS data quality, data use, and immunization program outcomes. Financial data were collected at the national, provincial, district, and health facility levels through record review and interviews. An activity-based costing approach was conducted from a health system perspective. RESULTS: NIIS data timeliness significantly improved from pre- to postintervention in both provinces. For example, the mean number of days from birth date to NIIS registration before and after intervention dropped from 18.6 (SD 65.5) to 5.7 (SD 31.4) days in Hanoi (P<.001) and from 36.1 (SD 94.2) to 11.7 (40.1) days in Son La (P<.001). Data from Son La showed that the completeness and accuracy improved, while Hanoi exhibited mixed results, possibly influenced by the COVID-19 pandemic. Data use improved; at postintervention, 100% (667/667) of facilities in both provinces used NIIS data for activities beyond monthly reporting compared with 34.8% (202/580) in Hanoi and 29.4% (55/187) in Son La at preintervention. Across nearly all antigens, the percentage of children who received the vaccine on time was higher in the postintervention cohort compared with the preintervention cohort. Up-front costs associated with developing and deploying the NIIS were estimated at US $0.48 per child in the study provinces. The commune health center level showed cost savings from changing from the paper system to the NIIS, mainly driven by human resource time savings. At the administrative level, incremental costs resulted from changing from the paper system to the NIIS, as some costs increased, such as labor costs for supportive supervision and additional capital costs for equipment associated with the NIIS. CONCLUSIONS: The Hanoi and Son La provinces successfully transitioned to paperless reporting while maintaining or improving NIIS data quality and data use. However, improvements in data quality were not associated with improvements in the immunization program outcomes in both provinces. The COVID-19 pandemic likely had a negative influence on immunization program outcomes, particularly in Hanoi. These improvements entail up-front financial costs.


Assuntos
COVID-19 , Pandemias , Criança , Humanos , Vietnã , Vacinação , Imunização
8.
Chem Biodivers ; 21(3): e202302105, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38269614

RESUMO

Four previously undescribed compounds named phyllancosides A and B (1 and 2), and phyllancochines A and B (3 and 4) together with ten known compounds (5-14) were isolated from the aerial parts of Phyllanthus cochinchinensis Spreng. Their chemical structures were elucidated on the basis of comprehensive analysis of IR, HR-ESI-MS, 1D and 2D NMR spectra. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) spectra. Compounds 3, 4, and 10 showed antimicrobial activity against E. faecalis, S. aureus, and B. cereus with the MIC values in range of 32-256 µg/mL. Compound 11 inhibited E. faecalis and B. cereus, and 7 inhibited S. aureus with the MIC values in range of 64-128 µg/mL. In addition, compounds 1, 3, 4, 8, and 9 showed significantly NO production inhibitory activity in LPS activated RAW 264.7 cells with IC50 values ranging from 36.57 to 56.34 µM.


Assuntos
Anti-Infecciosos , Lipopolissacarídeos , Animais , Camundongos , Células RAW 264.7 , Estrutura Molecular , Lipopolissacarídeos/farmacologia , Staphylococcus aureus , Óxido Nítrico , Componentes Aéreos da Planta/química , Anti-Infecciosos/análise
9.
Chem Biodivers ; : e202401608, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39185684

RESUMO

Phytochemical study on the methanol extract of the leaves of Phyllanthus reticulatus led to the isolation of two new compounds, phyllanreticosides A (1) and B (2) together with ten known ones (3-12). Their chemical structures were determined by HR-ESI-MS, NMR, and ECD spectra in comparison with the literature. Three ellagitannins, phyllanreticoside A (1), corilagin (3), and phyllanthusiin C (4) inhibited lipopolysaccharide(LPS)-induced nitric oxide production in RAW 264.7 cells with IC50 values of 63.2, 83.2, and 5.6 µM, respectively. In addition, compounds 1, 3, and 4 exhibited significantly antimicrobial activity (MICs: 16-128 µg/mL) towards some of seven microbial strains, including Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, and Candida albicans.

10.
Chem Biodivers ; 21(3): e202400124, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38279623

RESUMO

Two undescribed triterpenes, syzyfolium A (1) and syzyfolium B (2), together with twelve known compounds, terminolic acid (3), actinidic acid (4), piscidinol A (5), threo-dihydroxydehydrodiconiferyl alcohol (6), lariciresinol-4-O-ß-D-glucoside (7), icariol A2 (8), 14ß,15ß-dihydroxyklaineanone (9), garcimangosone D (10), (+)-catechin (11), myricetin-3-O-α-L-rhamnopyranoside (12), quercitrin (13), and 3, 4, 5-trimethoxyphenyl-(6'-O-galloyl)-O-ß-D-glucopyranoside (14) were isolated from the leaves of Syzygium myrsinifolium. Their chemical structures were determined by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 3 and 4 inhibited significantly α-glucosidase with IC50 values of 23.99 and 36.84, respectively, and compounds 1 and 2 inhibited significantly α-amylase with IC50 values of 35.48 and 43.65 µM, respectively.


Assuntos
Syzygium , Triterpenos , Syzygium/química , alfa-Glucosidases , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , alfa-Amilases , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química
11.
Chem Biodivers ; 21(2): e202301963, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38117264

RESUMO

Seven steroidal saponins including three new 16,23-cyclocholestanes (1-3) and one new pregane (4) were isolated from the roots of Dracaena cambodiana Pierre ex Gagnep. Their chemical structures were elucidated to be (23R,25R)-26-O-ß-D-glucopyranosyl-16,23-cyclocholesta-5,17(20)-dien-22-one-3ß,16α,26-triol-3-O-α-L-rhamnopyranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→3)]-ß-D-glucopyranoside (1), (23R,25R)-26-O-ß-D-glucopyranosyl-16,23-cyclocholesta-5,17,20(22)-trien-3ß,22,26-triol-3-O-α-L-rhamnopyranosyl-(1→3)-ß-D-glucopyranoside (2), (23R,25R)-16,23-cyclocholesta-5,16,20(22)-trien-3ß,22,26-triol-3-O-α-L-rhamnopyranosyl-(1→3)-ß-D-glucopyranoside (3), 3ß-[(O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-gluco-pyranosyl)oxy]-pregna-5,17(20)-diene-16-one-20-carboxylic acid 4''''-O-ß-D-glucopyranosylisopentyl ester (4), cambodianoside A (5), diosbulbiside C (6), and diosbulbiside D (7), by IR, HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1 and 4-7 inhibited nitric oxide (NO) production in lipopolysaccharide activated RAW 264.7 cells with IC50 values ranging from 19.03±1.84 to 67.92±3.81 µM, whereas compounds 2 and 3 were inactive with IC50 values over 100 µM.


Assuntos
Dracaena , Lipopolissacarídeos , Saponinas , Camundongos , Animais , Lipopolissacarídeos/farmacologia , Óxido Nítrico , Células RAW 264.7 , Trientina , Saponinas/farmacologia , Saponinas/química , Estrutura Molecular
12.
Chem Biodivers ; 21(2): e202301764, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38050750

RESUMO

Dracaena cambodiana Pierre ex Gagnep. is well known as a medicinal plant and widely distributed in Vietnam. Phytochemical investigation on the trunks of D. cambodiana lead to the isolation of four undescribed compounds (1-4) together with seven known ones (5-11). Their structures were determined to be pennogenin-24-yl-O-ß-D-glucopyranoside (1), 17α-hydroxycambodianoside C (2), (25R)-27-hydroxypenogenin 3-O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (3), (3ß,25R)-17α,22α-dihydroxy-furost-5-en-3-yl-O-α-L-rhamnopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside (4), dracagenin A (5), 1-O-ß-D-glucopyranosyl-2-hydroxy-4-allylbenzene (6), 1-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranosyl-2-hydroxy-allylbenzene (7), 2-O-α-L-rhamnopyranosyl-(1→6)-ß-D-glucopyranosyl-1-hydroxy-allylbenzene (8), cinnamrutinoside A (9), icariside D1 (10), and seco-isolariciresinol 9-O-ß-glucopyranoside (11) by extensive spectroscopic investigation, HR-ESI-MS, 1D and 2D NMR spectra. The anti-inflammatory activity of the isolated compounds was evaluated on macrophages. Compounds 1-6 significantly inhibited nitric oxide production in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Among them, compound 1 showed the best inhibitory activity with an IC50 value of 8.90±0.56 µM.


Assuntos
Derivados de Alilbenzenos , Dracaena , Saponinas , Lipopolissacarídeos/farmacologia , Estrutura Molecular , Óxido Nítrico , Saponinas/farmacologia , Saponinas/química , Glucosídeos/química , Glucosídeos/farmacologia
13.
Chem Biodivers ; 21(3): e202302123, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38253808

RESUMO

Three previously undescribed compounds named rauvolphyllas A-C (1-3), along with thirteen known compounds, 18ß-hydroxy-3-epi-α-yohimbine (4), yohimbine (5), α-yohimbine (6), 17-epi-α-yohimbine (7), (E)-vallesiachotamine (8), (Z)-vallesiachotamine (9), 16S-E-isositsirikine (10), Nb -methylisoajimaline (11), Nb -methylajimaline (12), ajimaline (13), (+)-lyoniresinol 3α-O-ß-D-glucopyranoside (14), (+)-isolarisiresinol 3α-O-ß-D-glucopyranoside (15), and (-)-lyoniresinol 3α-O-ß-D-glucopyranoside (16) were isolated from the aerial parts of Rauvolfia tetraphylla L. Their chemical structures were elucidated based on the extensive spectroscopic interpretation of HR-ESI-MS, 1D and 2D NMR spectra. The absolute configurations of 2 and 3 were determined by experimental ECD spectra. Compounds 5, 6, 7, and 11-13 exhibited nitric oxide production inhibition activity in LPS-activated RAW 264.7 cells with the IC50 values of 79.10, 44.34, 51.28, 33.54, 37.67, and 28.56 µM, respectively, compared to that of the positive control, dexamethasone, which showed IC50 value of 13.66 µM. The other isolates were inactive with IC50 values over 100 µM.


Assuntos
Alcaloides , Anisóis , Lignanas , Naftalenos , Rauwolfia , Animais , Camundongos , Lignanas/química , Células RAW 264.7 , Lipopolissacarídeos/farmacologia , Óxido Nítrico , Alcaloides/análise , Espectroscopia de Ressonância Magnética , Componentes Aéreos da Planta/química , Ioimbina , Estrutura Molecular
14.
Chem Biodivers ; : e202401273, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828879

RESUMO

Eight furostanol glycosides including five undescribed compounds, named tribufurostanosides A-E (1-5), and three known ones (6-8) were isolated from the fruits of Tribulus terrestris L. Their chemical structures were determined by the IR, HR-ESI-MS, 1D-, and 2D-NMR spectra. Furostanols 1-8 significantly inhibited nitric oxide production in LPS activated RAW 264.7 cells with IC50 values ranging from 14.2 to 64.7 µM, compared to that of the positive control compound, dexamethazone (IC50 13.6 µM).

15.
Chem Biodivers ; : e202401679, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136410

RESUMO

Phytochemical study on the methanol extract of the stems of Tinospora crispa (L.) Hook.f. & Thomson led to the isolation of thirteen compounds including three undescribed cis-clerodane-type furanoditerpenoids (1-3) and ten known ones (4-13). Their chemical structures were determined by IR, HR-ESI-MS, 1D-, and 2D-NMR spectra. Compounds 2-6 and 8 inhibited moderately NO production in LPS activated RAW 264.7 cell with the IC50 values of 83.5, 57.6, 75.3, 78.1, and 74.7 µM, respectively.

16.
Molecules ; 29(14)2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39064834

RESUMO

The development of highly efficient and stable visible-light-driven photocatalysts for the removal of herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) from water is still a challenge. In this work, Bi2MoO6 (BMO) materials with different morphology were successfully prepared via a simple hydrothermal method by altering the solvent. The morphology of the BMO material is mainly influenced by the solvent used in the synthesis (H2O, ethanol, and ethylene glycol or their mixtures) and to a lesser extent by subsequent thermal annealing. BMO with aggregated spheres and nanoplate-like structures hydrothermally synthesized in ethylene glycol (EG) and subsequently calcined at 400 °C (BMO-400 (EG)) showed the highest adsorption capacity and photocatalytic activity compared to other synthesized morphologies. Complete degradation of 2,4-D on BMO upon irradiation with a blue light-emitting diode (LED, λmax = 467 nm) was reached within 150 min, resulting in 2,4-dichlorophenol (2,4-DCP) as the main degradation product. Holes (h+) and superoxide radicals (⋅O2-) are assumed to be the reactive species observed for the rapid conversion of 2,4-D to 2,4-DCP. The addition of H2O2 to the reaction mixture not only accelerates the degradation of 2,4-DCP but also significantly reduces the total organic carbon (TOC) content, indicating that hydroxyl radicals are crucial for the rapid mineralization of 2,4-D. Under optimal conditions, the TOC value was reduced by 84.5% within 180 min using BMO-400 (EG) and H2O2. The improved degradation performance of BMO-400 (EG) can be attributed to its particular morphology leading to lower charge transfer resistance, higher electron-hole separation, and larger specific surface area.

17.
Environ Monit Assess ; 196(6): 514, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709331

RESUMO

Microplastics (MPs, plastic items from 1 µm to 5 mm in size) are present in all environmental compartments. The evaluation of their concentration, fate, and spatial distribution is still a challenge for the scientific community. This concern is just debuting in developing countries, (i.e., Asia, South America, and Africa). This study deals with the MP contamination in the abiotic marine compartments of Northern Vietnam: seawater and intertidal sediments. Four sites located in the intertidal zone or near the coastline in Tonkin Bay, Vietnam were studied. A total of 16 samples (eight for each compartment) were collected in July 2020 (rainy season) and January 2021 (dry season). Anthropogenic particles (total observed fibers and fragments) were found at levels ranging from 3 to 303 particles/m3 in seawater and from 63 to 955 particles/kg dry weight in sediments. Most of these were fibers less than 300-µm long. Higher levels of seawater at the Nam Dinh site were found in the rainy season compared to the dry one. As the river flow was estimated six times higher during the rainy season than during the dry season, these results suggest the river discharge is a potential source of contamination for the coastal zone. The temporal variability was lower for the sediments than for the seawater, suggesting the long-term integration of the anthropogenic particles in this compartment. A small portion of sorted particles were analyzed by µFTIR (8.35%), and this sub-sample was only composed of fragments. Still, fragments were mostly composed of polypropylene (PP, 82%), polyethylene (PE, 9%), and polystyrene (PS, 9%). The fragment size was similar in the two studied compartments, but it was dependent on polymer types since PS fragments (140 ± 17 µm) were smaller than those made of PE (622 ± 123 µm) and PP (869 ± 905 µm). Future works should investigate the smallest fraction of MP (even nanoplastics) as well as find solutions in order to mitigate MP contamination in the marine environment.


Assuntos
Baías , Monitoramento Ambiental , Sedimentos Geológicos , Microplásticos , Água do Mar , Poluentes Químicos da Água , Vietnã , Água do Mar/química , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Microplásticos/análise
18.
AIDS Behav ; 27(6): 1989-1997, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36441408

RESUMO

We examined gender differences among people who inject drug (PWID) in Hai Phong, Vietnam in term of blood-borne infections, risk behaviors, and access to care. Using respondent-driven-sampling surveys, we recruited 3146 PWID from 2016 to 2018. Inclusion criteria included a positive urine test for heroin and recent injection marks. There were 155 female PWID (4,9%), including 82 at RDS-2016, 32 at RDS-2017 and 38 at RDS-2018. The age mean was 36.3 ± 7.2 years. The majority of female PWID had less than high school education (90.9%) and were unemployed (51.3%). There was no difference in the proportion of HIV and HCV positive by gender. However, women had several significant differences in risk behaviors than men in multivariable logistic regression. Being a woman was independently associated with being unemployed, being a sex worker, having unstable housing, having uses drugs for less than 5 years, more use of methamphetamine, having a partner who ever injected drugs, and less access to methadone treatment. Interventions targeting female PWID are needed, possibly through community organizations and peer educators.


Assuntos
Usuários de Drogas , Infecções por HIV , Hepatite C , Abuso de Substâncias por Via Intravenosa , Masculino , Humanos , Feminino , Adulto , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/complicações , Vietnã/epidemiologia , Fatores Sexuais , Assunção de Riscos , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Hepatite C/complicações
19.
Chem Biodivers ; 20(8): e202300853, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37409765

RESUMO

A chemical study of the methanol extract of the aerial parts of Achyranthes aspera led to the isolation of four new flavonoid C-glycosides (1-4) along with eight known analogs (5-12). Their structures were elucidated by a combination of spectroscopic data analysis, HR-ESI-MS, 1D and 2D NMR spectra. All the isolates were evaluated their NO production inhibitory activity in LPS-activated RAW264.7 cells. Compounds 2, 4, and 8-11 showed significant inhibition with IC50 values ranging from 25.06 to 45.25 µM, compared to that of the positive control compound, L-NMMA, IC50 value of 32.24 µM, whereas the remaining compounds were weak inhibitory activity with IC50 values over 100 µM. This is the first report of 7 from Amaranthaceae family, and 11 from the genus Achyranthes.


Assuntos
Achyranthes , Flavonoides , Flavonoides/farmacologia , Flavonoides/química , Achyranthes/química , Óxido Nítrico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Glicosídeos/farmacologia , Glicosídeos/química , Estrutura Molecular
20.
Chem Biodivers ; 20(11): e202301296, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37842907

RESUMO

Vitex trifolia L. is a medicinal plant and widely distributed in the northern mountainous areas of Vietnam. Phytochemical study on the fruits of this plant led to the isolation of nine iridoid derivatives (1-9) including three undescribed compounds (1-3). Their structures were elucidated to be 3''-hydroxyscrophuloside A1 (1), 3''-hydroxycallicoside D (2), 2'-p-hydroxybenzoylaucubin (3), 6'-p-hydroxybenzoylmussaenosidic acid (4), nishindaside (5), agnuside (6), 10-O-vanilloylaucubin (7), 6'-O-p-hydroxybenzoyl-gardoside (8), and buddlejoside B (9) based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1, 2, 4, and 8 significantly posessed anti-barterial activity against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa strains with MIC values in range of 16-64 µg/mL. At concentration of 20 µM, compounds 1-9 did not show cytotoxic effects against human lung cancer cells (PC9).


Assuntos
Anti-Infecciosos , Antineoplásicos , Vitex , Humanos , Iridoides/química , Vitex/química , Frutas/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/análise , Extratos Vegetais/análise
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