Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Eixos temáticos
Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Molecules ; 29(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38999102

RESUMO

Activated carbon has an excellent porous structure and is considered a promising adsorbent and electrode material. In this study, activated carbon fibers (ACFs) with abundant microporous structures, derived from natural cotton fibers, were successfully synthesized at a certain temperature in an Ar atmosphere and then activated with KOH. The obtained ACFs were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), elemental analysis, nitrogen and carbon dioxide adsorption-desorption analysis, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and N2 adsorption-desorption measurement. The obtained ACFs showed high porous qualities and had a surface area from 673 to 1597 m2/g and a pore volume from 0.33 to 0.79 cm3/g. The CO2 capture capacities of prepared ACFs were measured and the maximum capture capacity for CO2 up to 6.9 mmol/g or 4.6 mmol/g could be achieved at 0 °C or 25 °C and 1 standard atmospheric pressure (1 atm). Furthermore, the electrochemical capacitive properties of as-prepared ACFs in KOH aqueous electrolyte were also studied. It is important to note that the pore volume of the pores below 0.90 nm plays key roles to determine both the CO2 capture ability and the electrochemical capacitance. This study provides guidance for designing porous carbon materials with high CO2 capture capacity or excellent capacitance performance.

2.
Fish Shellfish Immunol ; 139: 108911, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37394018

RESUMO

The present study aimed to evaluate the effects of dietary TPs on growth performance, intestinal digestion, microflora and immunity in juvenile hybrid sturgeon. A total of 450 fish (97.20 ± 0.18 g) were randomly divided into a standard diet (TP-0) or four treatments consisting of a standard diet supplemented with four concentrations of TPs (mg/kg): 100 (TP-100), 300 (TP-300), 500 (TP-500), and 1000 (TP-1000) for 56 days. The TP-300 significantly increased weight gain rate (WGR) and specific growth rate (SGR) (p < 0.05), and TP-1000 significantly increased the feed conversion ratio (FCR) (p < 0.05). TP-300 and TP-500 significantly increased intestinal trypsin, amylase, and lipase activities (p < 0.05). Besides, TP-300 significantly enhanced total antioxidant capacity (T-AOC) and the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) and decreased malondialdehyde (MDA) content (p < 0.05). Moreover, TP-300 decreased the expression levels of tumor necrosis factor-alpha (TNF-α), interleukin 8 (IL-8), and interleukin 1ß(IL-1ß) compared with TP-0 and TP-1000 (p < 0.05). In addition, the intestinal microbiota diversity in the TP-300 group was observably higher, the dominant microbiota was Bacteroidota, Cyanobacteria, Proteobacteria and Firmicutes at the phylum level, Enterobacteriaceae, Nostocaceae and Clostridiaceae at the family level. The relative abundances of potential probiotics including Rhodobacteraceae and potential pathogens especially Clostridiaceae were the highest, and lowest, respectively. In conclusion, TP-300 altered the abundance of microbial taxa, resulting in enhancing the intestinal digestion, antioxidant status and non-specific immunity to improve the growth performance in juvenile hybrid sturgeon.


Assuntos
Antioxidantes , Imunidade Inata , Animais , Antioxidantes/metabolismo , Suplementos Nutricionais , Peixes , Dieta/veterinária , Glutationa , Chá , Ração Animal/análise
3.
Gen Comp Endocrinol ; 337: 114260, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36933747

RESUMO

mHypoA-55 cells are kisspeptin-expressing neuronal cells originating from the arcuate nucleus of the mouse hypothalamus. These cells are called KNDy neurons because they co-express kisspeptin, neurokinin B, and dynorphin A. In addition, they express gonadotropin-releasing hormone (GnRH). Here, we found that kisspeptin 10 (KP10) increased Kiss-1 (encoding kisspeptin) and GnRH gene expression in kisspeptin receptor (Kiss-1R)-overexpressing mHypoA-55 cells. KP10 greatly increased serum response element (SRE) promoter activity, which is a target of extracellular signal-regulated kinase (ERK) (20.0 ± 2.54-fold). KP10 also increased cAMP-response element (CRE) promoter activity in these cells (2.32 ± 0.36-fold). KP10-increased SRE promoter activity was significantly prevented in the presence of PD098095, a MEK kinase (MEKK) inhibitor, and KP10-induced CRE promoter activity was also inhibited by PD098059. Similarly, H89, a protein kinase A (PKA) inhibitor, significantly inhibited the KP10 induction of SRE and CRE promoters. KP10-induced Kiss-1 and GnRH gene expressions were inhibited in the presence of PD098059. Likewise, H89 significantly inhibited the KP10-induced increase in Kiss-1 and GnRH. Transfection of mHypoA-55 cells with constitutively active MEKK (pFC-MEKK) increased SRE and CRE promoter activities by 9.75 ± 1.77- and 1.36 ± 0.12-fold, respectively. Induction of constitutively active PKA (pFC-PKA) also increased SRE and CRE promoter activities by 2.41 ± 0.42- and 40.71 ± 7.77-fold, respectively. Furthermore, pFC-MEKK and -PKA transfection of mHypoA-55 cells increased both Kiss-1 and GnRH gene expression. Our current observations suggest that KP10 increases both the ERK and PKA pathways and that both pathways mutually interact in mHypoA-55 hypothalamic cells. Activation of both ERK and PKA signaling might be necessary to induce Kiss-1 and GnRH gene expressions.


Assuntos
Hormônio Liberador de Gonadotropina , Kisspeptinas , Animais , Camundongos , Linhagem Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Kisspeptinas/genética , Kisspeptinas/metabolismo , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Transdução de Sinais
4.
Endocrine ; 83(3): 733-746, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37966704

RESUMO

OBJECTIVE: We examined how the sex steroids influence the synthesis of gonadotropins. MATERIALS AND METHODS: The effects of sex steroids estradiol (E2), progesterone (P4), and dihydrotestosterone (DHT) in pituitary gonadotroph cell model (LßT2 cells) in vitro and ovary-intact rats in vivo were examined. The effects of sex steroids on Kiss1 gene expression in the hypothalamus were also examined in ovary-intact rats. RESULTS: In LßT2 cells, E2 increased common glycoprotein alpha (Cga) and luteinizing hormone beta (Lhb) subunit promoter activity as well as their mRNA expression. Although gonadotropin subunit promoter activity was not modulated by P4, Cga and Lhb mRNA expression was increased by P4. DHT inhibited Cga and Lhb mRNA expression with a concomitant decrease in their promoter activity. During the 2-week administration of exogenous E2 to ovary-intact rats, the estrous cycle determined by vaginal smears was disrupted. P4 or DHT administration completely eliminated the estrous cycle. Protein expression of all three gonadotropin subunits within the pituitary gland was inhibited by E2 or P4 treatment in vivo; however, DHT reduced Cga expression but did not modulate Lhb or follicle-stimulating hormone beta subunit expression. E2 administration significantly repressed Kiss1 mRNA expression in a posterior hypothalamic region that included the arcuate nucleus. P4 and DHT did not modulate Kiss1 mRNA expression in this region. In contrast, P4 administration significantly inhibited Kiss1 mRNA expression in the anterior region of the hypothalamus that included the anteroventral periventricular nucleus. The expression of gonadotropin-releasing hormone (Gnrh) mRNA in the anterior hypothalamic region, where the preoptic area is located, appeared to be decreased by treatment with E2 and P4. CONCLUSION: Our findings suggest that sex steroids have different effects in the hypothalamus and pituitary gland.


Assuntos
Kisspeptinas , Ovário , Ratos , Feminino , Animais , Kisspeptinas/genética , Kisspeptinas/metabolismo , Hipotálamo/metabolismo , Gonadotropinas Hipofisárias/genética , Gonadotropinas Hipofisárias/metabolismo , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Estradiol/farmacologia , RNA Mensageiro/metabolismo , Di-Hidrotestosterona/farmacologia , Expressão Gênica
5.
Int J Endocrinol ; 2023: 3143347, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36941851

RESUMO

Ovariectomy (OVX) causes a depletion of circulating estradiol (E2) and influences hypothalamic kisspeptin neurons, which govern gonadotropin-releasing hormone (GnRH) release and ultimately gonadotropin secretion. In this study, we examined the changes induced by OVX on the anterior pituitary gland in female rats. OVX significantly increased the mRNA expression of gonadotropin α, luteinizing hormone (LH) ß, and follicle-stimulating hormone (FSH) ß subunits within the pituitary gland compared with control (sham-operated) rats, and this was completely suppressed by E2 supplementation. High-dose dihydrotestosterone supplementation also prevented the OVX-induced increase in the expression of the three gonadotropin subunits. GnRH receptor mRNA expression within the pituitary was significantly increased in OVX rats, and this increase was completely inhibited by E2 supplementation. The mRNA expression of the receptors for adenylate cyclase-activating polypeptide and kisspeptin was unchanged by OVX. Although the mRNA levels of inhibin α, ßA, and ßB subunits within the pituitary gland were not modulated by OVX, follistatin gene expression within the pituitary gland was increased by OVX, and this increase was completely inhibited by E2 supplementation after OVX. In experiments using a pituitary gonadotroph cell model (LßT2 cells), follistatin itself did not modulate the mRNA expression of gonadotropin LHß and FSHß subunits, and the GnRH-induced increase in the expression of these genes was slightly inhibited in the presence of follistatin. Our current observations suggest that OVX induces several characteristic changes in the pituitary gland of rats.

6.
Medicine (Baltimore) ; 99(50): e23652, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33327349

RESUMO

BACKGROUND: Polymorphisms in the cytochrome P450 2C19 (CYP2C19) gene have been reported to be associated with coronary heart disease (CHD), but the results were not consistently analyzed among different patient groups. To derive a more precise estimation of these associations, we will conduct a meta-analysis to investigate the polymorphisms of CYP2C19 in all published studies. METHODS: Electronic databases (Google Scholar, ISI Web of Science, Pubmed, Embase, China National Knowledge Infrastructure, Wanfang, and China Biological Medicine) will be used to search clinical case-control or cohort studies about CYP2C19 polymorphism and CHD published until November 2020. Two reviewers will independently select the study, extract the data, and evaluate the quality of the study. Odds ratios with 95% confidence interval will be used to evaluate the strength of the association between the CYP2C19 polymorphism and CHD susceptibility under 4 genetic models. Subgroup analysis will be conducted by different ethnicity and genotyping method. Sensitivity analysis will be performed via sequentially omitting each of the included studies 1 at a time. Begg funnel plots and Egger test will be used to examine the potential publication bias. All the statistical analyses will be performed using Review Manager 5.3 and Stata 12.0. RESULTS: This study will provide a better understanding of the association between CYP2C19 polymorphisms and coronary heart disease risk. CONCLUSION: The publication of this protocol will minimize the possibility of bias due to post hoc changes to the analysis protocol, thus helping to obtain reliable evidence. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/R7U93.


Assuntos
Doença das Coronárias/genética , Citocromo P-450 CYP2C19/genética , Predisposição Genética para Doença/genética , Doença das Coronárias/etnologia , Etnicidade , Predisposição Genética para Doença/etnologia , Técnicas de Genotipagem , Humanos , Metanálise como Assunto , Razão de Chances , Polimorfismo Genético , Reprodutibilidade dos Testes , Projetos de Pesquisa , Fatores de Risco , Revisões Sistemáticas como Assunto/métodos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa