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1.
Small ; 20(21): e2306612, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38126683

RESUMO

Healing of large calvarial bone defects remains challenging. An RNA-guided Split dCas12a system is previously harnessed to activate long non-coding RNA H19 (lncRNA H19, referred to as H19 thereafter) in bone marrow-derived mesenchymal stem cells (BMSCs). H19 activation in BMSCs induces chondrogenic differentiation, switches bone healing pathways, and improves calvarial bone repair. Since adipose-derived stem cells (ASCs) can be harvested more easily in large quantity, here it is aimed to use ASCs as an alternative cell source. However, H19 activation alone using the Split dCas12a system in ASCs failed to elicit evident chondrogenesis. Therefore, split dCas12a activators are designed more to co-activate other chondroinductive transcription factors (Sox5, Sox6, and Sox9) to synergistically potentiate differentiation. It is found that co-activation of H19/Sox5/Sox6 in ASCs elicited more potent chondrogenic differentiation than activation of Sox5/Sox6/Sox9 or H19 alone. Co-activating H19/Sox5/Sox6 in ASCs significantly augmented in vitro cartilage formation and in vivo calvarial bone healing. These data altogether implicated the potentials of the Split dCas12a system to trigger multiplexed gene activation in ASCs for differentiation pathway reprogramming and tissue regeneration.


Assuntos
Diferenciação Celular , Condrogênese , RNA Longo não Codificante , Fatores de Transcrição SOXD , Crânio , Fatores de Transcrição SOXD/metabolismo , Fatores de Transcrição SOXD/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Animais , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Tecido Adiposo/citologia , Células-Tronco/metabolismo , Células-Tronco/citologia , Osteogênese/genética
2.
Heliyon ; 9(11): e21274, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027850

RESUMO

In this study, the conversion of monosaccharides to 5-hydroxymethylfurfural (5-HMF) using different deep eutectic solvents (DESs) was investigated in various conditions. Among all the investigated DESs, [ChCl][trichloroacetic acid], based on choline chloride and trichloroacetic acid with the ratio 1:1, showed the highest catalytic activity. A maximum 5-HMF yield was 82 % for 1 h at 100 °C using [ChCl][trichloroacetic acid] as a catalyst from fructose. [ChCl][trichloroacetic acid] could be recovered and reused three times with a slight loss in activity. Our work demonstrated the low-cost and effective method for the synthesis of 5-HMF from carbohydrates.

3.
Heliyon ; 9(6): e16984, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484308

RESUMO

Wetlands are one of the most important ecosystems as habitats for many animal and plant species and are crucial for disaster mitigation, improving environmental quality, storing carbon, and responding to climate change. However, these sensitive ecosystems have been heavily affected by anthropogenic activities, including aquaculture. In this study, we used multitemporal satellite imagery integrated with a verified field survey method to map the coverage of the wetland ecosystem in the Dong Rui commune, Tien Yen district, Quang Ninh Province, Vietnam, five times for four periods from 1975 to 2022, with high accuracy (overall accuracy = 92.3%, Kappa = 0.91). The results showed that from 1975 to 2000, the area of mangrove forests declined sharply (by nearly 2,000 ha), mainly due to policies of development and conversion of land use. From 2000 to 2022, the mangrove forest area was gradually restored, while the area under aquaculture shrank. Anthropogenic impacts, especially the effects of local economic development, and conservation and developmental policies, are the main causes of continuous change in each short period. Our study demonstrates satellite imagery as an effective tool for assessing wetland ecosystem area fluctuations and assessing the extent of human impacts on this natural ecosystem. Our findings can serve as a basis for planning, conservation strategies, and sustainable development of wetland ecosystems and for improving the associated livelihoods of the communities.

4.
Ann Med ; 55(1): 1345-1353, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36974658

RESUMO

BACKGROUND: Fine motor performance may serve as an early warning sign for reduced cognitive function. Physical activity can help preserve cognitive function; however, the relationship between fine motor performance and physical activity is not well understood. Therefore, this study examined the relationship between fine motor performance and physical activity in individuals at risk for developing cognitive impairment (those with diabetes and/or non-alcoholic fatty liver disease (NAFLD)). PATIENTS AND METHODS: Individuals aged 25-69 with and without diabetes and NAFLD were enrolled. For this cross-sectional study, all participants completed the Human Activity Profile and fine motor performance tasks (Grooved Pegboard Test and Trail Making Test). RESULTS: There were 93 participants in the study (NAFLD only (n = 29); diabetes + NAFLD (n = 34), controls (n = 30)). Individuals with both diabetes and NAFLD were less physically active and performed slower on the fine motor performance task. A statistically significant correlation was found between physical activity and motor speed among those with NAFLD only (r = 0.436, p<.05), which remained statistically significant after controlling for body mass index (r = 0.385; p<.05). CONCLUSIONS: This study suggests that those with diabetes + NAFLD have lower levels of physical activity and slower fine motor performance. The relationship between physical activity and fine motor performance was only statistically significant in the group of individuals with NAFLD only. Future research needs to explore the mechanisms that impact fine motor performance and physical activity in individuals at risk for mild cognitive impairment. Individuals with diabetes and/or NAFLD should be identified, advised and encouraged to engage in physical activity.Key MessagesThose with NAFLD and T2DM have lower levels of physical activity and slower fine motor performance compared to controls and those with NAFLD only.Future research needs to explore the mechanisms that impact fine motor performance and physical activity in those with T2DM with or without NAFLD.Individuals with impaired fine motor performance should be identified and encouraged to engage in physical activity.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Diabetes Mellitus Tipo 2/complicações , Estudos Transversais , Disfunção Cognitiva/etiologia , Exercício Físico
5.
Heliyon ; 9(1): e12864, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685359

RESUMO

Remote sensing imagery is the most suitable tool for monitoring, managing, and evaluating land-use overlay fluctuations, especially forest cover for large areas. Free- and medium-resolution satellite imagery is a useful tool that allows scientific researchers and management organizations to monitor forest development in developing countries, such as Vietnam. In this study, we used SPOT 4 and Planet remote sensing data to assess land-use status fluctuations in the Kon Ha Nung Plateau area, Vietnam, between 2000 and 2021 (the overall accuracy was 90.52%, Kappa value = 0.89). The results showed that from 2000 to 2010, the rate of natural forest loss in this area was 0.32%/year, of which, more than 6500 ha were converted to other uses. Between 2010 and 2021, the rate of natural forest loss gradually decreased (0.09%/year) instead of fluctuating between different types of land use. The area of forests, perennial crop land, and annual crop land tended to increase from 2000 to 2010; however, from 2010 to 2021, the area of plantation forests decreased markedly, while the area of perennial crop land and annual crop land continued to expand. The analysis of the policies on forest management, exploitation, and protection was applied locally, to explain the causes of the change in spatiotemporal aspects of the types of land-use cover in the Kon Ha Nung Plateau. Restoring forest areas during 2010-2021 initially improved effectiveness in forest management and protection. Furthermore, the results provide a better understanding of the current position and role of the government apparatus, cadres, and ethnic minorities in socioeconomic development associated with forest protection and development on the Kon Ha Nung Plateau. The results of this study can help managers monitor annual forest-cover fluctuations based on free remote sensing imagery to reduce both the cost of management and surveying, yielding relatively accurate results.

6.
Int J Public Health ; 67: 1605354, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439280

RESUMO

Objectives: There is no study on Helicobacter pylori (H. pylori) infection in pupils of Ho Chi Minh city (HCMC), the most overcrowded city in Vietnam. Therefore, the aim of this study was to estimate the prevalence of H. pylori and its geographical spread among school-aged children. Methods: A school-based cross-sectional study was conducted among 1854 pupils across 24 districts of HCMC in 2019. Multiple-stage sampling method was used to enroll pupils. We built a four-points index for geographical division based on population density and employees density to evaluate the link between H. pylori and crowded level. Stool samples were analyzed by monoclonal enzyme-immunoassay stool antigen-test to assess the infection status. Logistic regression was performed to assess possible factors related to H. pylori infection. Results: The overall prevalence of H. pylori was 87.7%. There was a linear increasing trend in the infection rate (p < 0.001) across the 4-points index of HCMC and this trend maintained within both age and gender subgroups (p = 0.02). Conclusion: Prevalence of H. pylori was high and it increased with population density or employees density. Therefore, it is crucial to plan and implement the reduction of H. pylori infection programs by targeting the highly concentrated population areas of HCMC.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Criança , Humanos , Infecções por Helicobacter/epidemiologia , Prevalência , Estudos Transversais , Vietnã/epidemiologia
7.
Front Vet Sci ; 9: 853825, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35425836

RESUMO

African swine fever (ASF) is a contagious and lethal hemorrhagic disease with a case fatality rate approaching 100% in domestic pigs. The main objectives of this study were to describe the spatiotemporal analysis as well as to assess the potential risk factors along the pig value chain in Lao Cai province, Vietnam. A total of 925 outbreaks were reported from 2019 to 2020. The three clusters (primary, secondary and 5th) were observed near the Chinese border. The most temporal clusters were detected between May and August during the study period. In addition, we evaluated the association between ASF outbreak locations to the nearest main roads and elevation. For ASF outbreak locations to the nearest main roads, compared with the reference (<5,000 m), <1,000 m (10.22 times) and 1,000-2,000 m (1.98 times) were significantly higher occurrences of ASF. For elevation, compared to the reference (>1,500 m), the farm locations with <500 m (55.31 times) showed a significantly increased risk of ASF outbreaks. Farmers perceived that the highest risk of ASF transmission may come from collectors and slaughterers, intermediaries inside and outside the commune, feed agents and maize agents in the commune, and pig retailers. Both commercial and household pig producers considered minimizing the number of people going in and out of pig stables and improving healthcare and husbandry procedures to be both very important and feasible. There is a need for compliance by all pig producers and other actors in the pig value chain to adopt biosecurity practices. Therefore, awareness, knowledge and understanding of infection and risks of ASF need to be improved. Veterinary officials at the provincial and district levels need to improve capacity and resources to perform laboratory analysis for ASF and need to coordinate with local actors on the control and prevention of ASF in the community.

8.
PLoS One ; 14(5): e0216370, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31048899

RESUMO

Actinotrichia are the first exoskeletal elements formed during zebrafish fin development. These rigid fibrils serve as skeletal support for the fin fold and as substrates for mesenchymal cell migration. In the adult intact fins, actinotrichia are restricted to the distal domain of the fin. Following fin amputation, actinotrichia also reform during regeneration. The actinodin gene family codes for structural proteins of actinotrichia. We have previously identified cis-acting regulatory elements in a 2kb genomic region upstream of the first exon of actinodin1, termed 2P, required for tissue-specific expression in the fin fold ectoderm and mesenchyme during embryonic development. Indeed, 2P contains an ectodermal enhancer in a 150bp region named epi. Deletion of epi from 2P results in loss of ectodermal-specific activity. In the present study, we sought to further characterize the activity of these regulatory sequences throughout fin development and during adult fin regeneration. Using a reporter transgenic approach, we show that a site within the epi region, termed epi3, contains an early mesenchymal-specific repressor. We also show that the larval fin fold ectodermal enhancer within epi3 remains functional in the basal epithelial layer during fin regeneration. We show that the first non-coding exon and first intron of actinodin1 contains a transcriptional enhancer and an alternative promoter that are necessary for the persistence of reporter expression reminiscent of actinodin1 expression during adulthood. Altogether, we have identified cis-acting regulatory elements that are required for tissue-specific expression as well as full recapitulation of actinodin1 expression during adulthood. Furthermore, the characterization of these elements provides us with useful molecular tools for the enhancement of transgene expression in adulthood.


Assuntos
Nadadeiras de Animais/fisiologia , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regeneração/fisiologia , Proteínas de Peixe-Zebra/biossíntese , Peixe-Zebra/embriologia , Animais , Embrião não Mamífero/citologia , Elementos Facilitadores Genéticos/fisiologia , Éxons/fisiologia , Íntrons/fisiologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
9.
RSC Adv ; 8(24): 13142-13147, 2018 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35542508

RESUMO

Dye-sensitized Solar Cells (DSCs) based on ruthenium complex N719 as sensitizer have received much attention due to their affordability and high efficiency. However, their best performance is only achieved when using volatile organic solvents as electrolyte solutions, which are unstable under prolonged thermal stress. Thus, we developed a new series of 1-alkenyl-3-methylimidazolium trifluoromethanesulfonate ionic liquids used as robust DSC electrolytes. These ionic liquids exhibit low viscosity, high conductivity, and thermal stability. The implementation of 1-but-3-enyl-3-methyl-imidazolium trifluoromethanesulfonate, [ButMIm]OTf, into DSCs gave the best photovoltaic performance. The results are fairly comparable to those reports for other popular ionic liquid electrolytes currently used in DSC field. An insightful discussion on the relationship between the structure of these new ionic liquids and the J-V characterization as well as electrochemical impedance measurement of DSCs will give more interesting information. The results are useful for large-scale outdoor application of DSCs.

10.
Pest Manag Sci ; 72(6): 1071-89, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26853194

RESUMO

Cassava is a major staple, bio-energy and industrial crop in many parts of the developing world. In Southeast Asia, cassava is grown on >4 million ha by nearly 8 million (small-scale) farming households, under (climatic, biophysical) conditions that often prove unsuitable for many other crops. While SE Asian cassava has been virtually free of phytosanitary constraints for most of its history, a complex of invasive arthropod pests and plant diseases has recently come to affect local crops. We describe results from a region-wide monitoring effort in the 2014 dry season, covering 429 fields across five countries. We present geographic distribution and field-level incidence of the most prominent pest and disease invaders, introduce readily-available management options and research needs. Monitoring work reveals that several exotic mealybug and (red) mite species have effectively colonised SE Asia's main cassava-growing areas, occurring in respectively 70% and 54% of fields, at average field-level incidence of 27 ± 2% and 16 ± 2%. Cassava witches broom (CWB), a systemic phytoplasma disease, was reported from 64% of plots, at incidence levels of 32 ± 2%. Although all main pests and diseases are non-natives, we hypothesise that accelerating intensification of cropping systems, increased climate change and variability, and deficient crop husbandry are aggravating both organism activity and crop susceptibility. Future efforts need to consolidate local capacity to tackle current (and future) pest invaders, boost detection capacity, devise locally-appropriate integrated pest management (IPM) tactics, and transfer key concepts and technologies to SE Asia's cassava growers. Urgent action is needed to mobilise regional as well as international scientific support, to effectively tackle this phytosanitary emergency and thus safeguard the sustainability and profitability of one of Asia's key agricultural commodities. © 2016 Society of Chemical Industry.


Assuntos
Manihot , Controle de Pragas , Doenças das Plantas/prevenção & controle , Sudeste Asiático , Controle de Insetos , Manihot/microbiologia , Manihot/parasitologia , Doenças das Plantas/estatística & dados numéricos , Pesquisa
11.
Antimicrob Agents Chemother ; 57(7): 3240-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23629723

RESUMO

Vancomycin-intermediate Staphylococcus aureus (VISA) strains often arise by mutations in the essential two-component regulator walKR; however their impact on walKR function has not been definitively established. Here, we investigated 10 MRSA strains recovered serially after exposure of vancomycin-susceptible S. aureus (VSSA) JKD6009 to simulated human vancomycin dosing regimens (500 mg to 4,000 mg every 12 h) using a 10-day hollow fiber infection model. After continued exposure to the vancomycin regimens, two isolates displayed reduced susceptibility to both vancomycin and daptomycin, developing independent IS256 insertions in the walKR 5' untranslated region (5' UTR). Quantitative reverse transcription-PCR (RT-PCR) revealed a 50% reduction in walKR gene expression in the IS256 mutants compared to the VSSA parent. Green fluorescent protein (GFP) reporter analysis, promoter mapping, and site-directed mutagenesis confirmed these findings and showed that the IS256 insertions had replaced two SigA-like walKR promoters with weaker, hybrid promoters. Removal of IS256 reverted the phenotype to VSSA, showing that reduced expression of WalKR did induce the VISA phenotype. Analysis of selected WalKR-regulated autolysins revealed upregulation of ssaA but no change in expression of sak and sceD in both IS256 mutants. Whole-genome sequencing of the two mutants revealed an additional IS256 insertion within agrC for one mutant, and we confirmed that this mutation abolished agr function. These data provide the first substantial analysis of walKR promoter function and show that prolonged vancomycin exposure can result in VISA through an IS256-mediated reduction in walKR expression; however, the mechanisms by which this occurs remain to be determined.


Assuntos
Antibacterianos/farmacologia , Elementos de DNA Transponíveis , Staphylococcus aureus Resistente à Meticilina/genética , Resistência a Vancomicina/genética , Vancomicina/farmacologia , Proteínas de Bactérias/genética , Sequência de Bases , DNA Bacteriano/genética , Daptomicina/farmacologia , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Mutagênese Insercional , Mutagênese Sítio-Dirigida , Peptidoglicano Glicosiltransferase/genética , Regiões Promotoras Genéticas/genética , Proteínas Quinases/genética , Análise de Sequência de DNA
12.
J Chemother ; 25(1): 32-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23433442

RESUMO

AFN-1252, a potent enoyl-ACP reductase (FabI) inhibitor, is under development for the treatment of Staphylococcus aureus infections. The activity of AFN-1252 against two isolates of S. aureus, MSSA 26213 and MRSA S186, was studied in an in vitro pharmacodynamic model simulating AFN-1252 pharmacokinetics in man. Reductions in bacterial viable count over the first 6 hours were generally 1-2 logs and maximal reductions in viable count were generally achieved at fAUC/MIC ratios of 100-200. Maximum reductions in viable count against MSSA 29213 and MRSA S186 were approximately 4 logs, achieved by 450 mg q12h (fAUC/MIC = 1875) dosing at 28 hours. Staphylococcal resistance to AFN-1252 did not develop throughout the 48-hour experiments. As multidrug resistance continues to increase, these studies support the continued investigation of AFN-1252 as a targeted therapeutic for staphylococcal infections.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/farmacocinética , Benzofuranos/farmacologia , Benzofuranos/farmacocinética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pironas/farmacologia , Pironas/farmacocinética , Staphylococcus aureus/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Modelos Biológicos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/metabolismo
13.
BMC Infect Dis ; 11: 287, 2011 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-22026752

RESUMO

BACKGROUND: The development of hVISA has been associated with vancomycin clinical failures and is commonly misidentified in clinical microbiology laboratories. Therefore, the objectives of this present study was to improve the reliability of methodologies and criteria for identifying hVISA, evaluate the prevalence of hVISA among clinical bloodstream isolates of S. aureus and determine if there exists a relationship between accessory gene regulator (agr) dysfunction and the hVISA phenotype. METHODS: The presence of hVISA in 220 clinical S. aureus isolates (121 MSSA, 99 MRSA) from bloodstream infections was examined by CLSI broth microdilution, Macro & Standard Etest. Isolates which were classified as hVISA by Macro Etest, were additionally evaluated using a modified PAP-AUC method using a modified starting inoculum of 10(10) CFU/mL, and growth on brain heart infusion agar with 4 mg/L vancomycin (BHIV4) at 10(8) and 10(10) CFU/mL, and agr function was assessed by delta-hemolysin production. RESULTS: Broth microdilution MIC(50/90) of S.aureus and hVISA was 1.0/2.0 and 1.5/2.0 mg/L (p= 0.02), respectively. Macro Etest identified 12 (5.5%) hVISA isolates; higher among MRSA (9.1%) versus MSSA (2.5%) (p = 0.03). The mean modified PAP-AUC ratios (> 0.8) of 7 MRSA strains and 3 MSSA strains were significantly different (p = 0.001). 58% of hVISA strains were found to be agr dysfunctional when 21% of MRSA strains were agr dysfunctional. hVISA was detected among S. aureus bloodstream isolates, which were classified as susceptible among clinical microbiology laboratories. CONCLUSIONS: Evaluating the correlation between Etest MICs and modified PAP-AUC ratio values will add further improvement of discriminating hVISA, and agr dysfunction may be predictive of strains which display a greater predilection to display the hVISA phenotype.


Assuntos
Antibacterianos/farmacologia , Bacteriemia/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Transativadores/deficiência , Resistência a Vancomicina , Vancomicina/farmacologia , Proteínas de Bactérias , Contagem de Colônia Microbiana , Humanos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação
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