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1.
Sensors (Basel) ; 22(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35214469

RESUMO

Hollow carbon-coated In2O3 (C#In2O3) nanofibers were prepared using an efficiently combined approach of electrospinning, high-temperature calcination, and hydrothermal process. The polyaniline (PANI)/hollow C#In2O3 nanofiber composites were synthesized used hollow C#In2O3 nanofibers worked as a core through the in situ chemical oxidative polymerization. The morphology and crystalline structure of the PANI/hollow C#In2O3 nanofiber composite were identified using wide-angle X-ray diffraction and transmission electron microscopy. The gas-sensing performances of the fabricated PANI/hollow C#In2O3 nanofiber composite sensor were estimated at room temperature, and the response value of the composite sensor with an exposure of 1 ppm NH3 was 18.2, which was about 5.74 times larger than that of the pure PANI sensor. The PANI/hollow C#In2O3 nanofiber composite sensor was demonstrated to be highly sensitive to the detection of NH3 in the concentration range of 0.6~2.0 ppm, which is critical for kidney or hepatic disease detection from the human breath. This composite sensor also displayed superior repeatability and selectivity at room temperature with exposures of 1.0 and 2.0 ppm NH3. Because of the outstanding repeatability and selectivity to the detection of NH3 at 1.0 and 2.0 ppm confirmed in this investigation, the PANI/hollow C#In2O3 nanofiber composite sensor will be considered as a favorable gas-sensing material for kidney or hepatic disease detection from human breath.


Assuntos
Amônia , Nanofibras , Compostos de Anilina , Carbono , Humanos , Índio , Nanofibras/química , Temperatura
2.
Polymers (Basel) ; 13(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34771232

RESUMO

Hollow indium trioxide (In2O3) nanofibers fabricated via an effectively combined method of electrospinning and high-temperature calcination were coated with nitrogen-doped graphene quantum dots (N-GQDs) prepared by a hydrothermal process through electrostatic interaction. The N-GQD-coated hollow In2O3 nanofibers served as a core for the synthesis of polyaniline (PANI)/N-GQD/hollow In2O3 nanofiber ternary composites using in situ chemical oxidative polymerization. The chemical structure and morphology of the fabricated ternary composites were characterized using Fourier transform infrared, field-emission scanning electron microscopy, and transmission electron microscopy. The gas-sensing performances of the ternary composites were estimated by a homemade dynamic test system which was supplied with a real-time resistance acquisition platform at room temperature. The response value of the PANI/N-GQD/hollow In2O3 nanofiber sensor with a loading of 20 wt% N-GQD-coated hollow In2O3 nanofiber and an exposure of 1 ppm NH3 was 15.2, which was approximately more than 4.4 times higher than that of the PANI sensor. This ternary composite sensor was proved to be very sensitive in the detection of NH3 at a range of concentration between 0.6 ppm and 2.0 ppm at room temperature, which is crucial in the detection of hepatic or kidney disease in human breath. The PANI/N-GQD/hollow In2O3 nanofiber sensor also revealed higher selectivity and repeatability when exposed to 1.0 and 2.0 ppm NH3 at room temperature. Because of the excellent selectivity and repeatability in the detection of 1.0 and 2.0 ppm NH3 at room temperature achieved in this study, it is considered that the PANI/N-GQD/hollow In2O3 nanofiber composite sensor will be a favored gas-sensing material applied on human breath for the detection of hepatic or kidney disease.

3.
Polymers (Basel) ; 13(4)2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33673191

RESUMO

Thin-film composite (TFC) polyamide membranes formed through interfacial polymerization can function more efficiently by tuning the chemical structure of participating monomers. Accordingly, three kinds of diamine monomers were considered to take part in interfacial polymerization. Each diamine was reacted with trimesoyl chloride (TMC) to manufacture TFC polyamide nanofiltration (NF)-like forward osmosis (FO) membranes. The diamines differed in chemical structure; the functional group present between the terminal amines was classified as follows: aliphatic group of 1,3-diaminopropane (DAPE); cyclohexane in 1,3-cyclohexanediamine (CHDA); and aromatic or benzene ring in m-phenylenediamine (MPD). For FO tests, deionized water and 1 M aqueous sodium sulfate solution were used as feed and draw solution, respectively. Interfacial polymerization conditions were also varied: concentrations of water and oil phases, time of contact between the water-phase solution and the membrane substrate, and polymerization reaction time. The resultant membranes were characterized using attenuated total reflectance-Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy, and surface contact angle measurement to identify the chemical structure, morphology, roughness, and hydrophilicity of the polyamide layer, respectively. The results of FO experiments revealed that among the three diamine monomers, CHDA turned out to be the most effective, as it led to the production of TFC NF-like FO membrane with optimal performance. Then, the following optimum conditions were established for the CHDA-based membrane: contact between 2.5 wt.% aqueous CHDA solution and polysulfone (PSf) substrate for 2 min, and polymerization reaction between 1 wt.% TMC solution and 2.5 wt.% CHDA solution for 30 s. The composite CHDA-TMC/PSf membrane delivered a water flux (Jw) of 18.24 ± 1.33 LMH and a reverse salt flux (Js) of 5.75 ± 1.12 gMH; therefore, Js/Jw was evaluated to be 0.32 ± 0.07 (g/L).

4.
Antioxidants (Basel) ; 8(9)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491962

RESUMO

Studies have shown that diet and nutrition play significant roles in the prevention of depression and its clinical treatment. The present review aims to provide a clear understanding of the associations between diet patterns, specific foods, nutrients such as antioxidants, and depression. As a result, balanced dietary patterns such as the Mediterranean diet and certain foods such as fish, fresh vegetables, and fruits have been associated with a lower risk of depression or depressive symptoms, while high-fat Western diets and sugar-sweetened beverages have been associated with higher risk of depression or depressive symptoms. Dietary antioxidants such as green tea polyphenols or isoflavonoid intake have been negatively associated with depression or depressive symptoms. It is concluded that diet patterns, specific foods, and antioxidants play important roles in the prevention and clinical treatment of depression.

5.
Chemosphere ; 235: 543-549, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31279116

RESUMO

PURPOSE: Nonylphenol (NP) is one widely distributed representative of environmental estrogens that disturb reproductive activities, bone metabolism and brain function through interfering diverse signal pathways leading to hormone metabolic dysfunctions, immunologic derangement, and tumorigenesis. Few of previous studies have observed the subacute toxicity on rodents, and little has been focused on the mechanism underneath the toxicities observed. METHODS: The 32 male Sprague-Dawley (SD) rats were randomly divided into four groups, the negative control group (corn oil) NP low, medium and high dose groups [30, 90, 270 mg/(kg·d)]. SD rats administrated with different dosage of NP every other day for 28d. Elisa and RT-PCR was employed to observe estrogen metabolism markers or mRNA expressions. RESULTS: In serum, NP exposure caused testosterone (T) (p < 0.001), progesterone (PROG) (p < 0.05) and estrone (E1) (p < 0.05) increased. In testicle, NP exposure caused T (p < 0.001), PROG (p < 0.05), E1 (p < 0.05), 17ß-estradiol (E2) (p < 0.05) and ERα mRNA (p < 0.01) increased, while P450 aromatizing enzyme (p < 0.001) decreased in NPL and ERß mRNA (p < 0.001) decreased in NPM and NPH. In liver, NP exposure caused 17ß-HSD2 mRNA (p < 0.01) increased, while P450 aromatizing enzyme decreased (p < 0.05). CONCLUSION: NP exposure exhibited general and estrogenic toxicity in rats through disturbing estrogen secretion network and estrogen receptor expression network, inducing abnormal metabolism of estrogen, whether in serum, liver and testicle.


Assuntos
Disruptores Endócrinos/toxicidade , Estrogênios/metabolismo , Fígado/metabolismo , Fenóis/toxicidade , Testículo/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Estradiol/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Estrona/metabolismo , Feminino , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/metabolismo , Testosterona/metabolismo , Testes de Toxicidade
6.
Ecotoxicol Environ Saf ; 172: 523-529, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30743168

RESUMO

This study evaluated toxic effects of nonylphenol (NP) and octylphenol (OP) on central 5-hydroxytryptamine (5-HT) system and related learning and memory in the rats. Male Sprague-Dawley rats were exposed to NP (30, 90, or 270 mg/kg), OP (40, 120, or 360 mg/kg), or a mixture of NP and OP [(mixed with the corresponding NP, OP alone exposed low, medium and high dose according to the natural environment exists NP:OP = 4:1; NOL (24 mg/kg NP+8 mg/kg OP), NOM (72 mg/kg NP+24 mg/kg OP), NOH (216 mg/kg NP+72 mg/kg OP)] by gavage every other day for 30 d. Learning and memory were assessed using a passive-avoidance test. Levels of estrogen receptor ß (ERß), 5-HT, tryptophan hydroxylase 2 (TPH2), monoamine oxidase (MAOA) enzyme, serotonin transporter (SERT), the vesicular monoamine transporter 2 (VMAT2), 5-hydroxytryptamine 1 A (5-HT1A), 5-hydroxytryptamine 3 A (5-HT3A), 5-hydroxytryptamine 3B (5-HT3B), 5-hydroxytryptamine 4 A (5-HT4A) and 5-hydroxytryptamine 6 A (5-HT6A) were measured using ELISA kits. Levels of ERß, MAOA, SERT, VMAT2, 5-HT1A, 5-HT3A, 5-HT3B, 5-HT4A and 5-HT6A in rat hippocampal reduced by a high dose of NP and/or OP. Levels of TPH2 in rat midbrain and 5-HT in rat hippocampal increased by a high dose of NP and/or OP. In addition, latency was significantly shorter and errors were significantly greater in the high dose NP and NP+OP (NO) groups. Taken together, these results suggest that NP and/or OP may affect learning and memory in rats by inhibiting levels of ERß, which could then lead to decreases in levels of 5-HT1A, 5-HT3A, 5-HT3B, 5-HT4A, and 5-HT6A in the rat hippocampus. These findings suggested that separate and combined exposure to NP and OP could produce toxic effects on central 5-HT system and related learning and memory in the rats.


Assuntos
Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Fenóis/toxicidade , Serotonina/toxicidade , Animais , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Monoaminoxidase/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ratos , Ratos Sprague-Dawley , Triptofano Hidroxilase/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/metabolismo
7.
Nutrients ; 10(11)2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30405021

RESUMO

Adjusting dietary fat intake is reported to affect mitochondrial biogenesis and fatty acid oxidation (FAO), and thus may enhance exercise capacity. However, a high-fat diet where carbohydrate intake is not limited enough also makes it difficult for athletes to maintain weight, and may fail to force the body to utilize fat. As such, a low-carbohydrate, high-fat, ketogenic diet (KD) may be viable. We have previously reported that an eight-week KD enhances exercise capacity, and suggested the mechanism to be enhanced lipolysis and ketolysis. In the present study, we investigated how an eight-week KD alters mRNA expression during fatty acid mobilization, FAO and ketolysis. We found that an eight-week KD may remodel the lipid metabolism profile, thus contributing to influence exercise capacity. We also found that ketolysis, lipolysis and FAO adaptations may contribute to enhanced exhaustive exercise performance. Along with enhanced FAO capacity during exhaustive exercise, a KD may also alter IL-6 synthesis and secretion profile, thus contribute to fatty acid mobilization, ketolysis, lipolysis and preventing muscle damage. Both the lipid metabolism response and IL-6 secretion appeared to be muscle fiber specific. Taken together, the previous and present results reveal that an eight-week KD may enhance exercise performance by up-regulating ketolysis and FAO ability. Therefore, a KD may have the potential to prevent muscle damage by altering IL-6 secretion profile, indicating that a KD may be a promising dietary approach in endurance athletes, sports, and for injury prevention.


Assuntos
Dieta Cetogênica , Interleucina-6/sangue , Metabolismo dos Lipídeos/genética , Condicionamento Físico Animal , Ácido 3-Hidroxibutírico/sangue , Adiposidade , Animais , Ácidos Graxos não Esterificados/sangue , Regulação da Expressão Gênica , Glicogênio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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