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1.
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
2.
Environ Monit Assess ; 195(12): 1511, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37989961

RESUMO

Microplastic (MP) pollution is an emerging problem in many areas around the world and in coastal areas of Vietnam, requiring more studies dedicated to the accumulation of this pollutant in the food chain as well as its potential risk to human health. This study investigated MP levels in tissues of five common bivalve species collected from aquaculture areas along the coast of Vietnam. MPs were found in all bivalve samples, with average values of 10.84 ± 2.61 items/individual or 2.40 ± 1.34 items/g wet weight. Impacts of feeding habits of bivalves showed influences on MP abundance in the samples. Fibers were the dominant shape of MPs recorded, most of which accumulated in the gills and digestive glands of all bivalve samples, with the majority falling within the size range of 300-2000 µm. MPs found in all studied species had relatively similar chemical compositions, mainly composed of polypropylene (PP) and polyethylene (PE). In this study, a diverse diet consisting of different bivalve species and detailed data on the consumption rate of these species were used to assess the human health risk of MPs dedicated to the coastal communities of Vietnam. The results suggested a significant part of MP uptake by human could be via bivalve consumption, in which removing viscera and proper depuration should be applied prior to eating, thereby reducing the risk.


Assuntos
Bivalves , Poluentes Químicos da Água , Animais , Humanos , Microplásticos , Plásticos , Vietnã , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos
3.
Environ Res ; 209: 112843, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35101399

RESUMO

Pollution status and distribution characteristics of ten typical phthalic acid esters (PAEs) were investigated in 36 sediment samples collected from three rivers in Northern Vietnam from June to October 2020. The total concentrations of PAEs in sediment samples collected from the To Lich River (n = 9), the Nhue River (n = 12), and the Day River (n = 15) were in ranges of 11,000-125,000 ng/g-dwt (mean/median: 50,000/42,200 ng/g-dwt), 2140-89,900 ng/g-dwt (mean/median: 29,300/20,700 ng/g-dwt), and 1140-43,100 ng/g-dwt (mean/median: 13,800/10,400 ng/g-dwt), respectively. Among ten PAEs studied, di-(2-ethylhexyl) phthalate (DEHP) was found at the highest levels in all samples meanwhile dimethyl phthalate (DMP), diethyl phthalate (DEP), and dipropyl phthalate (DPP) were detected at low frequency and concentration. Significant correlations have existed between the median-chain (C4-C7) PAE pairs in sediment samples. Due to the high accumulation in the sediments, the median-chain PAEs had a higher ecological risk than the short-chain (C1-C3) PAEs. These contaminants may present a longstanding influence on organisms and ecosystems.


Assuntos
Ácidos Ftálicos , Poluentes Químicos da Água , China , Dibutilftalato , Ecossistema , Ésteres , Sedimentos Geológicos , Medição de Risco , Rios , Vietnã , Poluentes Químicos da Água/análise
4.
Environ Res ; 212(Pt A): 113244, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35398085

RESUMO

Health risks and perceptions of residents living nearby landfills or stone mines/quarries have been well documented; however, the multiple impacts of these two pollution sources have yet to be investigated. This study aims at giving insights into the impacts of residents exposed to two pollution sources in Danang city, Vietnam: Khanh Son landfill and Phuoc Tuong quarry. In this cross-sectional study, 7-point-Likert scale questionnaires were used to collect information from 314 respondents which were divided into three groups: i) Landfill-Stone mine (LS) exposed group within 1 km from both sources, ii) Stone mine (ST) exposed group within 1 km from the stone mine, and iii) the far-exposed group about 2-3 km from the two emission sites. Air pollutants (including H2S, CH4, and total suspended particles (TSP)) and noise levels were also sampled. In addition, we estimated the potential health risk assessment due to the exposure to hydrogen sulphide in the study areas. The findings have shown that 1) There is a statistical difference (p-value < 0.001) between the two exposed groups and far-exposed group regarding health risks and residents' perceptions; 2) Compared to the ST exposed group, the LS exposed group statistically showed a higher perception to bad odours and skin diseases; lower satisfaction with regards to the personal health condition and the operation of the landfill; and higher willingness to change current living locations; and 3) There is evidence to indicate that elevated concentrations of air pollutants are associated with the high self-reported health risks and residents' perceptions. Urgent actions should be focused on the LS exposed group, landfill and quarry operations to prevent further adverse health effects.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Estudos Transversais , Humanos , Vietnã , Instalações de Eliminação de Resíduos
5.
Environ Monit Assess ; 194(2): 65, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34993616

RESUMO

Microplastics (MPs) are small (< 5 mm) plastic particles that are widely found in marine, freshwater, terrestrial and atmospheric environments. Due to their prevalence and persistence, MPs are considered an emerging contaminant of environmental concern. The separation and quantitation of MPs from freshwater sediments is a challenging and critical issue. It is necessary to identify the fate and sources of MPs in the environment, minimise their release and adverse effects. Compared to marine sediments, standardised methods for extracting and estimating the amount of MPs in freshwater sediments are relatively limited. The present study focuses on MP recovery efficiency of four commonly used salt solutions (NaCl, NaI, CaCl2 and ZnCl2) for isolating MPs during the density separation step from freshwater sediment. Known combinations of artificial MP particles (PS, PE, PVC, PET, PP and HDPE) were spiked into standard river sediment. Extraction using NaI, ZnCl2 and NaCl solutions resulted in higher recovery rates from 37 to 97% compared to the CaCl2 solution (28-83%) and varied between polymer types. Low-density MPs (PE, HDPE, PP and PS) were more effectively recovered (> 87%) than the denser polymers (PET and PVC: 37 to 88.8%) using NaCl, NaI and ZnCl2 solutions. However, the effective flotation of ZnCl2 and NaI solutions is relatively expensive and unsafe to the environment, especially in the context of developing countries. Therefore, considering the efficiency, cost and environmental criteria, NaCl solution was selected. The protocol was then tested by extracting MPs from nine riverine sediment samples from the Red River Delta. Sediments collected from urban rivers were highly polluted by MPs (26,000 MPs items·kg-1 DW) compared to sediments located downstream. Using a NaCl solution was found to be effective in this case study and might also be used in long-term and large-scale MP monitoring programmes in Vietnam.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Poluentes Químicos da Água/análise
6.
Environ Res ; 197: 111158, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33887272

RESUMO

Comprehensive and updated information about polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) in surface sediments from Hanoi, the capital city of Vietnam, is rather scarce. In this study, concentrations and profiles of 209 PCBs, 41 polybrominated diphenyl ethers (PBDEs), 2,2',4,4',5,5'-hexabromobiphenyl (BB-153), hexabromocyclododecane (HBCD), pentabromoethylbenzene (PBEB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and decabromodiphenyl ethane (DBDPE) were determined in sediment samples collected from the Red River and some inner-city rivers of Hanoi. Concentrations (ng/g dry weight, median and range) of pollutants decreased in the order: DBDPE (28; not detected ND - 59) ≈ PCBs (27; 1.7-50) > PBDEs (23; 0.20-61) > HBCD (1.2; ND - 5.2) > BTBPE (0.46; ND - 3.6) > BB-153 (0.004; ND - 0.014) > PBEB (ND). Pollutant levels in the inner-city river sediments were about one to two orders of magnitude higher than those measured in the Red River main stream sediments. Tri-to hexa-CBs are major homologs but detailed profiles vary between individual samples, reflecting source and/or seasonal variations. CB-11 and CB-209 were found at higher proportions in sediments than in technical PCB mixtures, suggesting their novel sources from pigments. Deca-BDE and DBDPE are the most predominant BFRs with an increasing trend predicted for DBDPE. A preliminary ecological risk assessment was conducted for these pollutants in sediments. Total PCBs and deca-BDE in a few inner-city river sediments may exhibit adverse effects on benthic organisms, but no serious risk was estimated in general.


Assuntos
Retardadores de Chama , Bifenilos Policlorados , Monitoramento Ambiental , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Vietnã
7.
Bull Environ Contam Toxicol ; 107(3): 475-486, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33760936

RESUMO

Unsubstituted and methylated polycyclic aromatic hydrocarbons (22 PAHs and 17 Me-PAHs) were examined in surface sediments collected from the Red River and four inner-city rivers of Hanoi City, Vietnam. Concentrations of total PAHs and Me-PAHs ranged from 52 to 920 (median 710) and from 70 to 2600 (median 1000) ng/g dry weight in samples of dry and wet seasons, respectively. Significant correlation was observed between total PAHs and organic carbon contents (Spearman's ρ = 0.782; p < 0.05). PAHs were more abundant than Me-PAHs in all samples and dominated by 4-6 ring compounds. The most predominant PAHs were benzo[ghi]perylene, benzo[b/j]fluoranthene, chrysene, pyrene, fluoranthene, and phenanthrene. Methylated derivatives of naphthalene, phenanthrene, anthracene, and benz[a]anthracene were frequently detected. The patterns of PAHs indicated principal pyrogenic sources (notably gasoline exhaust) in this highly urbanized area. The occurrence of several PAHs were occasionally associated with adverse effects on benthic organisms of the inner-city rivers.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Vietnã , Poluentes Químicos da Água/análise
8.
Pharm Biol ; 59(1): 1464-1472, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34726583

RESUMO

CONTEXT: Sargassum horneri (Turner) C. Agardh (Sargassaceae) is a brown marine alga used in oriental medicine to treat allergic conditions. OBJECTIVE: This study clarifies the effect of polyphenol-containing S. horneri ethanol extract (SHE) on T-helper type-2 (Th2) polarisation. MATERIALS AND METHODS: All mice (BALB/c mice, n = 12) except in the healthy control group were first sensitised with an intraperitoneal injection of ovalbumin (OVA; 20 µg) and alum (2 mg) on Day 0 and Day 14. Similarly, phosphate-buffered saline (PBS) was injected according to the same schedule into the healthy control mice. After the final administration, splenocytes were obtained. OVA sensitised mice were challenged with OVA (100 µg/mL) in the absence or presence (62.5 and 125 µg/mL) of SHE while healthy control group remained untreated. RESULTS: SHE (0-1000 µg/mL) was not cytotoxic to splenocytes and demonstrated IC50 values of 3.27 and 3.92 mg/mL, respectively, at 24 and 48 h of incubation. SHE suppressed cell proliferation at concentrations ≥62.5 µg/mL. SHE treatment (125 µg/mL) subdued (by 1.8-fold) the population expansion of CD3+CD4+ helper T cells induced by OVA challenge. SHE attenuated the OVA-induced activation of respective transcription factors GATA3 and NLRP3. Simultaneously, highly elevated levels of cytokines interleukin (IL)-4 and IL-5 caused by OVA stimulation were removed completely and IL-13 suppressed by 1.5-fold. CONCLUSIONS: SHE exhibits Th2 immune suppression under OVA stimulation via GATA3- and NLRP3-dependent IL-4, IL-5, and IL-13 suppression. Therefore, SHE could be therapeutically useful for alleviating the symptoms of allergen-mediated immune diseases.


Assuntos
Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Sargassum/química , Células Th2/imunologia , Animais , Citocinas/imunologia , Relação Dose-Resposta a Droga , Fator de Transcrição GATA3/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ovalbumina , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Polifenóis/isolamento & purificação , Fator de Transcrição STAT5/metabolismo , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia
9.
J Public Health Manag Pract ; 24 Suppl 2: S9-S18, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29369252

RESUMO

BACKGROUND: Global progress in reducing maternal mortality requires improving access to maternal and child health services for the most vulnerable groups. This article reports results of implementation research that aimed to increase the acceptability of village-based ethnic minority midwives (EMMs) by local communities in Vietnam through implementing an integrated interventions package. METHODS: The study was carried out in 2 provinces in Vietnam, Dien Bien and Kon Tum. A quasi-experimental survey with pretest/posttest design was adopted, which included 6 months of intervention implementation. The interventions package included introductory "launch" meetings, monthly review meetings at community health centers, and 5-day refresher training for EMMs. A mixed-methods approach was used involving both quantitative and qualitative data. A structured questionnaire was used in the pre- and posttest surveys, complemented by in-depth interviews and focus group discussions with EMMs, relatives of pregnant women, community representatives, and health managers. RESULTS: Introductions of EMMs to their local communities by local authorities and supervision of performance of EMMs contributed to significant increases in utilization of services provided by EMMs, from 58.6% to 87.7%. Key facilitators included information on how to contact EMMs, awareness of services provided by EMMs, and trust in services provided by EMMs. The main barriers to utilization of EMM services, which may affect sustainability of the EMM scheme, were low self-esteem of EMMs and small allowances to EMMs, which also affected the recognition of EMMs in the community. CONCLUSIONS: Providing continuous support and integration of EMMs within frontline service provision and ensuring adequate local budget for monthly allowances are the key factors that should allow sustainability of the EMM scheme and continued improvement of access to maternal and child health care among poor ethnic minority people living in mountainous areas in Vietnam.


Assuntos
Tocologia/estatística & dados numéricos , Saúde das Minorias/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adulto , Etnicidade/estatística & dados numéricos , Feminino , Grupos Focais/métodos , Humanos , Saúde das Minorias/etnologia , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Gravidez , Pesquisa Qualitativa , População Rural/estatística & dados numéricos , Inquéritos e Questionários , Vietnã
10.
J Public Health Manag Pract ; 24 Suppl 2: S19-S27, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29369253

RESUMO

BACKGROUND: Gender inequalities influence the utilization of maternal health services in Vietnam, but little research has been published. This study, therefore, aimed to explore the association between gender inequalities and women's utilization of maternal health services in Vietnam. METHODS: The study was conducted in 8 provinces in the South Central Coast region of Vietnam during August 2013 to May 2014. A total of 907 women who delivered a year prior to the date of interview participated in the study. A multiple logistic regression model was used to examine the association between gender inequalities (including sociodemographic determinants of health) and utilization of 4 or more antenatal care (ANC4+) services, institutional delivery, and ever used contraceptive methods. RESULTS: The utilization rate of maternal health services was varied, from 53.9% for ANC4+ to 87.7% for ever used a contraceptive method and 97% for institutional delivery. Ethnicity was identified as the most influential variable out of all sociodemographic determinants of health. Regarding gender inequalities, couple communication was the only variable having significant association with women's utilization of maternal health services. CONCLUSION: Women's equal role within context of their daily life and relations with their husbands (discussing maternal care with husband and having equal income to husband) supported their use of maternal health services. Therefore, there should be concerted efforts from all relevant stakeholders including the health system to focus on disadvantaged women in planning and delivery of maternal health services, especially to ethnic minority women. Male involvement strategy should be implemented to promote maternal health care, especially during the prenatal and postpartum period. To provide more culturally sensitive and right-based approaches in delivery of maternal health services to disadvantaged women in Vietnam, interventions are recommended that promote male involvement, that is, to engage men in service delivery to adapt and ensure the most appropriate and effective maternal health care.


Assuntos
Serviços de Saúde Materna/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Sexismo/tendências , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Gravidez , Inquéritos e Questionários , Vietnã
11.
Environ Monit Assess ; 190(2): 67, 2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29308572

RESUMO

Planktons are a major component of food web structure in aquatic ecosystems. Their distribution and community structure are driven by the combination and interactions between physical, chemical, and biological factors within the environment. In the present study, water quality and the community structure of phytoplankton and zooplankton were monthly investigated from January to December 2015 at 11 sampling sites along the gradient course of the Day River (Red River Delta, northern Vietnam). The study demonstrated that the Day River was eutrophic with the average values of total phosphorus concentration 0.17 mg/L, total nitrogen concentration 1.98 mg/L, and Chl a 54 µg/L. Microscopic plankton analysis showed that phytoplankton comprised 87 species belonging to seven groups in which Chlorophyceae, Bacillariophyceae, and Cyanobacteria accounted for the most important constituents of the river's phytoplankton assemblage. A total 53 zooplankton species belonging to three main groups including Copepoda, Cladocera, and Rotatoria were identified. Plankton biomass values were greatest in rainy season (3002.10-3 cell/L for phytoplankton and 12.573 individuals/m3 for zooplankton). Using principal correspondence and Pearson correlation analyses, it was found that the Day River was divided into three main site groups based on water quality and characteristics of plankton community. Temperature and nutrients (total phosphorus and total nitrogen) are key factors regulating plankton abundance and distribution in the Day River.


Assuntos
Monitoramento Ambiental , Plâncton/fisiologia , Poluição da Água/análise , Animais , Biomassa , Clorófitas , Cladocera , Cianobactérias , Diatomáceas , Ecossistema , Cadeia Alimentar , Nitrogênio/análise , Fósforo/análise , Fitoplâncton/fisiologia , Chuva , Rios/química , Estações do Ano , Vietnã , Poluição da Água/estatística & dados numéricos , Qualidade da Água , Zooplâncton/fisiologia
12.
Environ Monit Assess ; 189(10): 490, 2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28884325

RESUMO

This research reports the presence of species Cylindrospermopsis raciborskii and cylindrospermopsin (CYN) in the Huong River and the relationship between species with environmental factors to find a scientific basis for predicting the risk of pollution of the species and CYN in waters. Strains of C. raciborskii isolated from the river were also identified as potentially toxin-producing through the determination of the presence of toxins in the cultures by ELISA; the presence of the genes involved by PCR confirms the CYN-producing ability of species C. raciborskii from this water body. Our results have confirmed the presence of toxic cyanobacteria C. raciborskii in the Huong River. C. raciborskii from the Huong River are mostly solitary, straight trichomes. Analyses of all C. raciborskii strains from the Huong River by ELISA for cylindrospermopsin were positive. The contents of cylindrospermopsin (CYN) in each strain were different, ranging from 5.25 ng mg-1 wet weight in CR1DD to 70.83 ng mg-1 wet weight in CR1NY. PCR analysis confirmed that the genes involved in the production of this cyanotoxin were present in C. raciborskii. The relationship between densities and toxicity showed a correlation coefficient R of 0.88. This was a relatively high positive correlation index, indicating the close links between densities and toxins: toxin CYN concentrations increased when C. raciborskii densities increased.


Assuntos
Toxinas Bacterianas/análise , Cylindrospermopsis/isolamento & purificação , Monitoramento Ambiental/métodos , Rios/química , Uracila/análogos & derivados , Poluentes Químicos da Água/análise , Alcaloides , Toxinas de Cianobactérias , Cylindrospermopsis/genética , Uracila/análise , Vietnã
13.
Cell Tissue Res ; 359(1): 145-60, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24825413

RESUMO

Beginning with their discovery in the context of stem cell fate choice in Caenorhabditis elegans, the microRNA (miRNA) let-7 and the RNA-binding protein Lin28 have been recognized as a regulatory pair with far-reaching impact on stem cell behavior in a wide range of organisms and tissues, including the mammalian brain. In this review, we describe molecular interactions between Lin28 and let-7 and the biological role that each plays in implementing stem cell programs that either maintain stem cell self-renewal and plasticity or drive lineage commitment and differentiation. For Lin28, considerable progress has been made in defining let-7-dependent and let-7-independent functions in the maintenance of pluripotency, somatic cell reprogramming, tissue regeneration, and neural stem cell plasticity. For the pro-differentiation activity of let-7, we focus on emerging roles in mammalian neurogenesis and neuronal function. Specific targets and pathways for let-7 have been identified in embryonic and adult neurogenesis, including corticogenesis, retinal specification, and adult neurogenic niches. Special emphasis is given to examples of feedback and feedforward regulation, in particular within the miRNA biogenesis pathway.


Assuntos
MicroRNAs/metabolismo , Neurogênese , Células-Tronco Pluripotentes/metabolismo , Animais , Redes Reguladoras de Genes , Humanos , Regeneração , Cicatrização
14.
J Neurochem ; 130(6): 733-47, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24766199

RESUMO

Treatments to inhibit or repair neuronal cell damage sustained during focal ischemia/reperfusion injury in stroke are largely unavailable. We demonstrate that dietary supplementation with the antioxidant di-tert-butyl-bisphenol (BP) before injury decreases infarction and vascular complications in experimental stroke in an animal model. We confirm that BP, a synthetic polyphenol with superior radical-scavenging activity than vitamin E, crosses the blood-brain barrier and accumulates in rat brain. Supplementation with BP did not affect blood pressure or endogenous vitamin E levels in plasma or cerebral tissue. Pre-treatment with BP significantly lowered lipid, protein and thiol oxidation and decreased infarct size in animals subjected to middle cerebral artery occlusion (2 h) and reperfusion (24 h) injury. This neuroprotective action was accompanied by down-regulation of hypoxia inducible factor-1α and glucose transporter-1 mRNA levels, maintenance of neuronal tissue ATP concentration and inhibition of pro-apoptotic factors that together enhanced cerebral tissue viability after injury. That pre-treatment with BP ameliorates oxidative damage and preserves cerebral tissue during focal ischemic insult indicates that oxidative stress plays at least some causal role in promoting tissue damage in experimental stroke. The data strongly suggest that inhibition of oxidative stress through BP scavenging free radicals in vivo contributes significantly to neuroprotection. We demonstrate that pre-treatment with ditert-butyl bisphenol(Di-t-Bu-BP) inhibits lipid, protein, and total thiol oxidation and decreases caspase activation and infarct size in rats subjected to middle cerebral artery occlusion (2 h) and reperfusion (24 h) injury. These data suggest that inhibition of oxidative stress contributes significantly to neuroprotection.


Assuntos
Antioxidantes/farmacologia , Compostos Benzidrílicos/farmacologia , Fármacos Neuroprotetores , Fenóis/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Reação de Fase Aguda/genética , Reação de Fase Aguda/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Western Blotting , Encéfalo/patologia , Caspase 3/metabolismo , Caspase 7/metabolismo , Dieta , Eletroforese em Gel de Poliacrilamida , Metabolismo Energético/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/prevenção & controle , Masculino , Oxirredução , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia , Acidente Vascular Cerebral/patologia , Compostos de Sulfidrila/metabolismo
15.
Zootaxa ; 3785: 25-37, 2014 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24872168

RESUMO

We describe a distinctive new species of phytotelm-breeding rhacophorid frog from central Vietnam. Gracixalus lumarius sp. nov. is distinguished from all other rhacophorids in Indochina by a combination of (1) medium body size (adult males 38.9-41.6 mm; adult female 36.3 mm), (2) dorsum brown diurnally and yellow nocturnally, (3) venter pink, (4) tympanum and supratympanic fold indistinct (5) iris dark gold with a dense, relatively uniformly distributed network of black reticulations, (6) dorsum with distinctive white conical tubercles in males, and (7) eggs deposited on wall of a phyptotelm. The new species is known from montane bamboo and montane evergreen forest in Ngoc Linh Nature Reserve in Kon Tum Province, between ~1845-2160 m elevation.


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Animais , Anuros/genética , Demografia , Ecossistema , Feminino , Masculino , Filogenia , Reprodução/fisiologia , Especificidade da Espécie , Árvores , Vietnã
16.
Environ Sci Pollut Res Int ; 31(15): 22362-22379, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38409380

RESUMO

Urban rivers are significantly impacted by anthropogenic pressure. This study presents the updated assessment of the concentrations of 11 metals and other variables (pH, total organic carbon (TOC) and nutrients (total nitrogen, total phosphorus, and total silica)) in the sediments of four urban rivers in inner Hanoi city, Vietnam, during the period 2020-2022. The mean concentrations of Fe, Zn, As, and Cr were higher than the permissible values of the Vietnam National technical regulation on the surface sediment quality. Moreover, Zn and Cr were at the severe effect level of the US EPA guidelines for sediment quality. The calculation of pollution indices (Igeo and EF) demonstrated that Mn, Ni, and Fe were from natural sources whereas other metals were from both anthropogenic and natural sources. The ecological risk index revealed that metals in Hanoi riverine sediments were classified at considerable ecological risk. High values of metals, TOC, and nutrients in the sediments of these urban rivers mostly originate from the accumulation of untreated urban wastewater that is enhanced by low river discharge. Our results may provide scientific base for better management decisions to ensure environmental protection and sustainable development of Hanoi city.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Metais Pesados/análise , Vietnã , Rios , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Monitoramento Ambiental/métodos , Ásia , Medição de Risco , China
17.
J Nutr Biochem ; 124: 109504, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37944673

RESUMO

Asthma is an inflammatory disease characterized by chronic inflammation in lung tissues and excessive mucus production. High-fat diets have long been assumed to be a potential risk factor for asthma. However, to date, very few direct evidence indicating the involvement of high sucrose intake (HSI) in asthma progression exists. In this study, we investigate the effect of HSI on ovalbumin (OVA)-sensitized allergic asthma mice. We observed that HSI increased the expression of inflammatory genes (IL-1ß, IL-6, TNF-α) in adipose tissues and led to reactive oxygen species generation in the liver and lung. In addition, HSI accelerated the TLR4/NF-κB signaling pathway leading to MMP9 activation, which promotes the chemokines and TGF-ß secretion in the lungs of OVA-sensitized allergic asthma mice. More importantly, HSI significantly promoted the pathogenic Th2 and Th17 responses. The increase of IL-17A secretion by HSI increased the expression of chemokines (MCP-1, CXCL1, CXCL5, CXCL8). It resulted in eosinophil and mast cell infiltration in the lung and trachea. We also demonstrated that HSI increased mucus hypersecretion, which was validated by increased main mucin protein (MUC5AC) secreted in the lungs. Our findings suggest that HSI exacerbates the development of Th2/Th17-predominant asthma by upregulating the TLR4-mediated NF-κB pathway, leading to excessive MMP9 production.


Assuntos
Asma , Metaloproteinase 9 da Matriz , Camundongos , Animais , Ovalbumina/efeitos adversos , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Camundongos Endogâmicos C57BL , Asma/metabolismo , Pulmão , Inflamação/metabolismo , Quimiocinas/metabolismo , Sacarose/efeitos adversos , Camundongos Endogâmicos BALB C , Modelos Animais de Doenças , Líquido da Lavagem Broncoalveolar
18.
Bioimpacts ; 14(1): 27652, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327632

RESUMO

Introduction: Patient-derived induced pluripotent stem cells (iPSCs) have been widely used as disease models to test new therapeutic strategies. Moreover, the regenerative potential of stem cells can be improved with the use of biologically active compounds. Our study was designed to explore the effect of honokiol, a small polyphenol molecule extracted from Magnolia officinalis, on the survival and culture time of iPSC-derived neurons from a sporadic Alzheimer's disease (AD) patient. This study aimed to generate iPSCs from peripheral blood mononuclear cells (PBMCs) of an AD patient using episomal plasmids with a nucleofector system and differentiate them into neurons. These iPSC-derived neurons were used to investigate the effect of honokiol extracted from M. officinalis on their survival and long-term cultures. Methods: IPSCs were generated from PBMCs of an AD patient by introducing Oct-3/4, Sox2, Klf4, L-Myc, and Lin28 using NucleofectorTM Technology. Differentiation of neurons derived from iPSCs was carried out using inducers and recognized by biomarkers. The viability of iPSC-derived neurons with the addition of honokiol extracted from the bark of M. officinalis was determined by the MTT analytical kit. Results: IPSCs were generated by reprogramming AD patient-derived PBMCs and subsequently converted into neurons. The survival and growth of iPSC-derived neurons were significantly enhanced by adding honokiol in the experiment conditions. Conclusion: AD iPSC-derived neurons had a high viability rate when cultured in the presence of honokiol. These results have shown that AD iPSC-derived neurons can be an excellent model for screening neurotrophic agents and improving the conditions for long-term cultures of human iPSC-derived neurons. Honokiol proves to be a potential candidate for cellular therapeutics against neurodegenerative disorders.

19.
Asia Eur J ; 21(1): 1-21, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36686969

RESUMO

This paper provides a historical overview regarding the emergence, development and deepening of divergences between the European Union (EU) and the People's Republic of China (China) in reducing global aviation emissions. It focuses on their divergences on three specific issues, i.e. under which framework to tackle global aviation emissions, whether and how to reflect the Common but Differentiated Responsibilities and Respective Capabilities (CBDR-RC) principle in the design and implementation of the global market-based measures (MBMs) for international aviation and which role the International Civil Aviation Organization (ICAO) should play in offsetting these emissions. Besides, this paper explains the driving forces behind these divergences by examining both normative and economic-related factors, which have formed different stances of both sides. From a Chinese perspective, considerations about the issues of state sovereignty, fairness regarding burden sharing in tackling climate change, the development of China's aviation and aircraft manufacturing and its limited capability in promoting the large-scale SAF deployment help explain its hardline stance on reducing global aviation emissions. As for the EU, perceptions of its leading role in the global climate governance and the CBDR-RC principle, the targets of strengthening the EU ETS role in the global carbon market, and the competitiveness of the European airlines are underlying reasons behind its attempt to include the international aviation under its ETS. Moreover, the EU member states' support to the ICAO can be explained through the conformity between the emissions offsetting objectives under this organisation and the EU's current climate policies.

20.
PLoS One ; 18(12): e0279691, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38085730

RESUMO

INTRODUCTION: Breastfeeding has many benefits for mothers, children, and the environment over both the short and longr-term. Prenatal intention to breastfeed is a powerful predictor of short-term breastfeeding outcomes. OBJECTIVE: This study aims to analyze breastfeeding intentions, including the intention to feed infants with breastmilk only and to continue exclusive breastfeeding to 6 months among pregnant mothers in Hanoi, Vietnam. METHODS: The analysis included 1230 singleton mothers, between 24- and 36-weeks' gestation, who attended antenatal clinics in two hospitals in Hanoi in 2020. RESULTS: The proportion of mothers with an "breastfeeding intention" (i.e., intention to feed an infant with breastmilk only) and "exclusive breastfeeding intention" to 6 months was 59.9% and 41.7%, respectively. Mothers who were 25 years or older (aOR = 1.35, 95%CI:1.00-1.81), had an undergraduate educational degree or higher (aOR = 1.38, 95%CI: 1.08-1.76), had observed another woman breastfeeding (aOR = 1.43, 95%CI: 1.03-2.00), were not living with parents-in-law (aOR = 1.34, CI: 1.05-1.70), and were multiparous (aOR = 1.60, 95%CI: 1.16-2.19) had higher odds of "exclusive breastfeeding intention" to 6 months. Among primiparous women, those who thought their husbands support breastfeeding were more likely to intend to feed an infant with breastmilk only. Among multiparous women, feeding the previous child with breastmilk exclusively before the introduction of complementary foods and not giving solid foods together with water until 6 months, were significant predictors for both breastfeeding intentions. CONCLUSION: Mothers without exclusive breastfeeding experience should be provided with greater support to promote exclusive breastfeeding intention and outcomes.


Assuntos
Aleitamento Materno , Intenção , Lactente , Criança , Feminino , Gravidez , Humanos , Estudos Transversais , Vietnã , Mães , Vitaminas
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