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1.
Artigo em Inglês | MEDLINE | ID: mdl-37740802

RESUMO

Water contamination becomes one of the most high-priority environmental concerns, calling for the efficient treatment techniques. Bionanocomposites can be robust adsorbents, but the synthesis requires toxic chemicals or energy consuming and cause the secondary pollution. Green nanocomposites can be biogenically synthesized using the plant extract to end up with a critically safe strategy. Herein, we used the flower extract of Combretum indicum plant as a bio-based reductant and carbonaceous source for the green CuO@C nanocomposite. This green nanoadsorbent obtained a specific surface area of 17.33 m2/g, good crystallinity, and functional group-containing surface, i.e., -OH and -CONH-. We also conducted the optimization of parameters, i.e., concentration, CuO@C dose, pH, time, and temperature, and reached removal efficiencies towards malachite green (MG, 83.23%), Congo red (CR, 84.60%), brilliant blue (BB, 71.39%), and methylene blue (MB, 23.67%). The maximum adsorption capacities were found as ordered, MG (46.387 mg/g) > MB (23.154 mg/g) > BB (22.8 mg/g) > CR dye (11.063 mg/g). Through the intra-particle diffusion kinetic model, MG and BB adsorption endured a three-step process, while CR and MB adsorption was a two-step process. The recyclability of the green CuO@C nanocomposite was three cycles with 67.54% for the final cycle of BB removal. Moreover, the nanoadsorbent displayed a high stability, checked by X-ray diffraction, FT-IR analysis, EDX spectra, and SEM images. It is recommended that the green CuO@C nanocomposite biosynthesized using the Combretum indicum flower extract can be a good alternative for the dye treatment from wastewater.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34765008

RESUMO

Recently, plant-derived anti-inflammatory products have received an increasing attention from researchers due to their excellent in vivo activity with limited side effects. Therefore, the extraction of natural active compounds from the plant with high purity for use in anti-inflammatory formulations is required. In this study, oily Capsicum oleoresin (OCO) was extracted from Capsicum frutescens L. in ethanol by the ultrasound-assisted extraction technique, followed by a centrifugation step for a high purity OCO extract, which can be applied to develop anti-inflammatory formulations. The impact of various conditions (ethanol concentration, sonicating temperature, extraction time, solvent-to-sample ratio, and extraction repetition) on the efficiency of the extraction process was investigated. The results showed that the optimized conditions for the high yield of OCO were 95% ethanol, 50-60°C, 60 minutes, solvent-to-sample ratio of 5 : 1 ml/g, and one extraction repetition, followed by centrifuging at 5000 rpm in 2 hours. Then, the purity and in vivo anti-inflammatory activities of the obtained OCO was then determined by using the HPLC method and carrageenan-induced mice paw edema model, respectively. The purity of OCO was determined as 3.408 mg capsaicin per gram of Capsicum powder; meanwhile, its anti-inflammatory effect value was approximate to that of the commercial drug diclofenac after 48 hours of treatment. The high purity OCO prepared by this low-cost and ecofriendly extraction process would be a promising material for anti-inflammatory formulations.

3.
Polymers (Basel) ; 14(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35012136

RESUMO

Polyamidoamine dendrimer (PAMAM) with its unique characteristics emerges as a potential drug delivery system which can prolong releasing time, reduce the side effects but still retaining treatment efficiency. In this study, methoxy polyethylene glycol modified PAMAM generation 3.0 (G3.0@mPEG) is prepared and characterized via 1H-NMR, FT-IR, and TEM. Subsequently, two antiretroviral agents (ARV) including lamivudine (3TC) and zidovudine (AZT) are individually encapsulated into G3.0@mPEG. The drug-loading efficiency, drug release profile, cytotoxicity and anti-HIV activity are then evaluated. The results illustrate that G3.0@mPEG particles are spherical with a size of 34.5 ± 0.2 nm and a drug loading content of about 9%. Both G3.0@mPEG and ARV@G3.0@mPEG show no cytotoxicity on BJ cells, and G3.0@mPEG loading 3TC and AZT performs sustained drug release behavior which is best fitted with the Korsmeyer-Peppas model. Finally, the anti-HIV activity of ARV via Enzymatic Assay of Pepsin is retained after being loaded into the G3.0@mPEG, in which about 36% of pepsin activity was inhibited by AZT at the concentration of 0.226 mM. Overall, PAMAM G3.0@mPEG is a promising nanocarrier system for loading ARV in HIV treatment and prevention.

4.
Cells Tissues Organs ; 209(2-3): 101-109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32541153

RESUMO

The aim of this study was to develop a porcine epiphyseal plate-derived extracellular matrix powder (PEPEP) for epiphyseal plate regeneration. PEPEP was characterized by chemical assay to determine the contents of DNA and epiphyseal plate complex chemical components (glycosaminoglycan and hydroxyproline). The effects of PEPEP on the viability, proliferation, and differentiation of human bone marrow mesenchymal stem cells (hBMSCs) were also evaluated. hBMSCs cultured in PEPEP exhibited a good distribution with excellent viability after 72 h, demonstrating the ability of PEPEP to support hBMSC proliferation. At week 4 and 6 in vitro, the PEPEP + hBMSCs structure showed chondrogenic ability and an increase in expression of collagen type I, type II, and type X. PEPEP showed a promising ability to enhance cartilage formation and promote chondrocyte differentiation, maturation, and hypertrophy. The results provide insights into the feasibility of PEPEP as a potential material for tissue engineering applications.


Assuntos
Epífises/metabolismo , Matriz Extracelular/metabolismo , Lâmina de Crescimento/metabolismo , Animais , Adesão Celular , Sobrevivência Celular , Células Cultivadas , Matriz Extracelular/ultraestrutura , Humanos , Células-Tronco Mesenquimais/citologia , Pós , Suínos
5.
Environ Manage ; 55(5): 1080-92, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25588807

RESUMO

One of the prerequisites of the REDD+ mechanism is to effectively predict business-as-usual (BAU) scenarios for change in forest cover. This would enable estimation of how much carbon emission a project could potentially prevent and thus how much carbon credit should be rewarded. However, different factors like forest degradation and the lack of linearity in forest cover transitions challenge the accuracy of such scenarios. Here we predict and validate such BAU scenarios retrospectively based on forest cover changes at village and district level in North Central Vietnam. With the government's efforts to increase the forest cover, land use policies led to gradual abandonment of shifting cultivation since the 1990s. We analyzed Landsat images from 1973, 1989, 1998, 2000, and 2011 and found that the policies in the areas studied did lead to increased forest cover after a long period of decline, but that this increase could mainly be attributed to an increase in open forest and shrub areas. We compared Landsat classifications with participatory maps of land cover/use in 1998 and 2012 that indicated more forest degradation than was captured by the Landsat analysis. The BAU scenarios were heavily dependent on which years were chosen for the reference period. This suggests that hypothetical REDD+ activities in the past, when based on the remote sensing data available at that time, would have been unable to correctly estimate changes in carbon stocks and thus produce relevant BAU scenarios.


Assuntos
Comércio , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Política Ambiental/tendências , Florestas , Carbono/análise , Política Ambiental/economia , Vietnã
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