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1.
BMC Public Health ; 24(1): 1163, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664654

RESUMO

BACKGROUND: The global spread of COVID-19 has brought immense physiological and psychological distress to students, such as test anxiety and poor sleep quality. This study aims to explore the relationship between COVID-19 stress and test anxiety and the mediating roles of intolerance of uncertainty and sleep quality between them. METHODS: A study was conducted in China during the late stage of the pandemic. A total of 936 Chinese art students (age M = 18.51, SD = 2.11, 46.6% female) completed the Coronavirus Stress Measure (CSM), the 12-item Intolerance of Uncertainty (IUS-12), the Brief Version of the Pittsburgh Sleep Quality Index (B-PSQI), and the Test Anxiety Inventory (TAI). A chain mediation model analysis was conducted to examine the mediating effects of intolerance of uncertainty and sleep quality on the association with COVID-19 stress and test anxiety. RESULTS: COVID-19 stress was positively associated with test anxiety (ß = 0.50, p < 0.001). The intolerance of uncertainty and sleep quality partially and serially mediated the relationship between COVID-19 stress and test anxiety (ß = 0.01, 95% CI = 0.01 to 0.02). CONCLUSION: These findings suggest that art students' intolerance of uncertainty and sleep quality partially and serially mediate the relation between COVID-19 stress and test anxiety. The results have significant implications for the intervention and prevention of test anxiety, providing additional evidence for the relationship between COVID-19 stress and test anxiety.


Assuntos
COVID-19 , Qualidade do Sono , Estresse Psicológico , Estudantes , Humanos , Feminino , COVID-19/psicologia , COVID-19/epidemiologia , Incerteza , Masculino , China/epidemiologia , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Adulto Jovem , Adolescente , Estresse Psicológico/psicologia , Estresse Psicológico/epidemiologia , Ansiedade aos Exames/psicologia , Ansiedade aos Exames/epidemiologia , Adulto
2.
Small ; 19(25): e2208045, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36929607

RESUMO

Alkaline membrane water electrolysis is a promising production technology, and advanced electrocatalyst and membrane electrode design have always been the core technology. Herein, an ion-exchange method and an environmentally friendly in situ green phosphating strategy are successively employed to fabricate Ru-Ru2 P heterogeneous nanoparticles by using hydroxyapatite (HAP) as a phosphorus source, which is an exceptionally active electrocatalyst for hydrogen evolution reaction (HER). Density functional theory calculation results reveal that strong electronic redistribution occurs at the heterointerface of Ru-Ru2 P, which modulates the electronic structure to achieve an optimized hydrogen adsorption strength. The obtained Ru-Ru2 P possesses excellent HER performance (24 mV at 10 mA cm-2 ) and robust stability (1000 mA cm-2 for 120 h) in alkaline media. Furthermore, an environmentally friendly membrane electrode with a sandwich structure is assembled by HAP nanowires as an alkaline membrane, Ru-Ru2 P as a cathodic catalyst, and NiFe-LDH as an anodic catalyst, respectively. The voltage of (-) Ru-Ru2 P || NiFe-LDH/CNTs (+) (1.53 V at 10 mA cm-2 ) is lower than that of (-) 20 wt% Pt/C || RuO2 (+) (1.60 V at 10 mA cm-2 ) for overall water splitting. Overall, the studies not only design an efficient catalyst but also provide a new route to achieve a high-stability electrolyzer for industrial H2 production.

3.
Magn Reson Med ; 89(1): 64-76, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36128884

RESUMO

PURPOSE: To develop an ultrafast and robust MR parameter mapping network using deep learning. THEORY AND METHODS: We design a deep learning framework called SuperMAP that directly converts a series of undersampled (both in k-space and parameter-space) parameter-weighted images into several quantitative maps, bypassing the conventional exponential fitting procedure. We also present a novel technique to simultaneously reconstruct T1rho and T2 relaxation maps within a single scan. Full data were acquired and retrospectively undersampled for training and testing using traditional and state-of-the-art techniques for comparison. Prospective data were also collected to evaluate the trained network. The performance of all methods is evaluated using the parameter qualification errors and other metrics in the segmented regions of interest. RESULTS: SuperMAP achieved accurate T1rho and T2 mapping with high acceleration factors (R = 24 and R = 32). It exploited both spatial and temporal information and yielded low error (normalized mean square error of 2.7% at R = 24 and 2.8% at R = 32) and high resemblance (structural similarity of 97% at R = 24 and 96% at R = 32) to the gold standard. The network trained with retrospectively undersampled data also works well for the prospective data (with a slightly lower acceleration factor). SuperMAP is also superior to conventional methods. CONCLUSION: Our results demonstrate the feasibility of generating superfast MR parameter maps through very few undersampled parameter-weighted images. SuperMAP can simultaneously generate T1rho and T2 relaxation maps in a short scan time.


Assuntos
Aceleração , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Estudos Prospectivos , Processamento de Imagem Assistida por Computador/métodos , Algoritmos
4.
Theor Appl Genet ; 136(4): 87, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971843

RESUMO

KEY MESSAGE: We identified and fine-mapped S58, a selfish genetic locus from Asian rice that confers hybrid male sterility in crosses between Asian and African cultivated rice, and found a natural neutral allele in Asian rice lines that will be useful for overcoming S58-mediated hybrid sterility. Hybrids between Asian cultivated rice (Oryza sativa L.) and African cultivated rice (Oryza glaberrima Steud) display severe hybrid sterility (HS), hindering the utilization of strong heterosis in hybrids between these species. Several African rice selfish loci causing HS in Asian-African cultivated rice hybrids have been identified, but few such Asian rice selfish loci have been found. In this study, we identified an Asian rice selfish locus, S58, which causes hybrid male sterility (HMS) in hybrids between the Asian rice variety 02428 and the African rice line CG14. Genetic analysis confirmed that S58 causes a transmission advantage for the Asian rice S58 allele in the hybrid offspring. Genetic mapping with near-isogenic lines and DNA markers delimited S58 to 186 kb and 131 kb regions of chromosome 1 in 02428 and CG14, respectively, and revealed complex genomic structural variation over these mapped regions. Gene annotation analysis and expression profiling analyses identified eight anther-expressed candidate genes potentially responsible for S58-mediated HMS. Comparative genomic analysis determined that some Asian cultivated rice varieties harbor a 140 kb fragment deletion in this region. Hybrid compatibility analysis showed that this large deletion allele in some Asian cultivated rice varieties can serve as a natural neutral allele, S58-n, that can overcome S58-mediated interspecific HMS. Our study demonstrates that this selfish genetic element from Asian rice is important for HMS between Asian and African cultivated rice, broadening our understanding of interspecific HS. This study also provides an effective strategy for overcoming HS in future interspecific rice breeding.


Assuntos
Infertilidade Masculina , Oryza , Masculino , Humanos , Oryza/genética , Melhoramento Vegetal , Mapeamento Cromossômico , Loci Gênicos , Infertilidade Masculina/genética
5.
J Sci Food Agric ; 103(5): 2554-2563, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36494898

RESUMO

BACKGROUND: Hyperlipidemia is regarded as a public health matter, and its effective prevention and treatment are urgently required. However, the treatment of hyperlipidemia is still relatively scarce. RESULTS: Fermented Cerasus humilis fruit (FCHF) had higher total flavonoid, total phenolic, procyanidin, and organic and free amino acid content, and lower total sugar content, than non-fermented C. humilis fruit (NFCHF). Both FCHF and NFCHF treatment significantly prevent putting on weight. Furthermore, FCHF administration ameliorated hyperlipidemia and cholesterol over-accumulation. In addition, FCHF administration activated the antioxidase system and decreased the malondialdehyde content to relieve oxidative stress, and showed more efficaciously than NFCHF administration. FCHF treatments significantly reverse the fat deposition in high-fat diet rat liver. FCHF supplementation can relieve the dysbacteriosis induced by hyperlipidemia, and regulate the composition of rat gut microbiota by increasing the abundance of Prevotella and norank_f_Muribaculaceae. CONCLUSION: Lactobacillus plantarum and Saccharomyces cerevisiae fermentation enhanced the antihyperlipidemic property of C. humilis fruits by promoting gut microbiota regulation. © 2022 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Hiperlipidemias , Ratos , Animais , Frutas/química , Hiperlipidemias/metabolismo , Dieta Hiperlipídica , Estresse Oxidativo
6.
J Sci Food Agric ; 103(15): 7721-7738, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37439182

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver cirrhosis and cancer. Lonicerae flos polysaccharides (LPs) have been shown to be effective in treating metabolic diseases; however, the therapeutic effects and underlying molecular mechanisms of LPs in NAFLD remain unclear. PURPOSE: The objective of this study was to investigate the morphological characterization of Lonicerae flos polysaccharides (LPs) and the mechanism of LPs in relieving NAFLD. METHODS: The morphology of LPs was observed using atomic force microscopy (AFM), X-ray diffraction (XRD), thermal weight (TG), and thermal weight derivative (DTG); NAFLD mice were treated with LPs at the same time as they were induced with a Western diet, and then the indexes related to glycolipid metabolism, fibrosis, inflammation, and autophagy in the serum and liver of the mice were detected. RESULTS: The atomic force microscope analysis results indicated that the LPs displayed sugar-chain aggregates, exhibited an amorphous structure, and were relatively stable in thermal cracking at 150 °C. It was also found that LPs exerted therapeutic effects in NAFLD. The LPs prevented high-fat and -cholesterol diet-induced NAFLD progression by regulating glucose metabolism dysregulation, insulin resistance, lipid accumulation, inflammation, fibrosis, and autophagy. Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) inhibitor compound C abrogated LP-induced hepatoprotection in mice with NAFLD. The LPs further treated NAFLD by reshaping the structure of the gut microbiota, in which Desulfovibrio bacteria plays a key roles. CONCLUSION: Lonicerae flos polysaccharides exert protective effects against NAFLD in mice by improving the structure of the intestinal flora and activating the AMPK signaling pathway. © 2023 Society of Chemical Industry.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Lipopolissacarídeos , Proteínas Quinases Ativadas por AMP/metabolismo , Fígado/metabolismo , Metabolismo dos Lipídeos , Inflamação/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , Fibrose , Adenosina/metabolismo , Adenosina/farmacologia , Adenosina/uso terapêutico , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL
7.
Ecotoxicol Environ Saf ; 230: 113174, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34999342

RESUMO

This study aimed to investigate the structure characteristics Lonicera flos polysaccharides (LP) and the protective effects of LP on cyclophosphamide-induced immunosuppression in mice. The results showed the yield and purity of LP was 1.41% and 94.15%, the molecular weight was 53 kDa, and composed of arabinose, rhamnose, ribose, xylose, mannose, fructose, galactose and glucose; and LP had typical polysaccharide structural characteristics via ultraviolet and Fourier transform infrared (FTIR) spectroscopy, 1H NMR and 13C NMR spectra, and scanning electron microscopy (SEM) analyses. Furthermore, LP obviously alleviated the injury of spleen and thymus; significantly promoted Interleukin-2 (IL-2), IL-6, tumor necrosis factor α (TNF-α), immunoglobulin (IgA, IgG and IgM) secretion; and improved the richness of gut microbiota and the contents of short-chain fatty acids (SCFAs) in immunosuppressive mice. Taken together, these results suggested that LP possessed strong protective effect on cyclophosphamide-induced immunosuppression in mice via modulating gut microbiota.

8.
Magn Reson Med ; 86(6): 3334-3347, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34309073

RESUMO

PURPOSE: To develop a deep learning-based reconstruction framework for ultrafast and robust diffusion tensor imaging and fiber tractography. METHODS: SuperDTI was developed to learn the nonlinear relationship between DWIs and the corresponding diffusion tensor parameter maps. It bypasses the tensor fitting procedure, which is highly susceptible to noises and motions in DWIs. The network was trained and tested using data sets from the Human Connectome Project and patients with ischemic stroke. Results from SuperDTI were compared against widely used methods for tensor parameter estimation and fiber tracking. RESULTS: Using training and testing data acquired using the same protocol and scanner, SuperDTI was shown to generate fractional anisotropy and mean diffusivity maps, as well as fiber tractography, from as few as six raw DWIs, with a quantification error of less than 5% in all white-matter and gray-matter regions of interest. It was robust to noises and motions in the testing data. Furthermore, the network trained using healthy volunteer data showed no apparent reduction in lesion detectability when directly applied to stroke patient data. CONCLUSIONS: Our results demonstrate the feasibility of superfast DTI and fiber tractography using deep learning with as few as six DWIs directly, bypassing tensor fitting. Such a significant reduction in scan time may allow the inclusion of DTI into the clinical routine for many potential applications.


Assuntos
Aprendizado Profundo , Substância Branca , Anisotropia , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Humanos , Processamento de Imagem Assistida por Computador , Substância Branca/diagnóstico por imagem
9.
New Phytol ; 225(5): 2108-2121, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31622519

RESUMO

Epigenetic modifications have emerged as an important mechanism underlying plant defence against pathogens. We examined the role of JMJ14, a Jumonji (JMJ) domain-containing H3K4 demethylase, in local and systemic plant immune responses in Arabidopsis. The function of JMJ14 in local or systemic defence response was investigated by pathogen growth assays and by analysing expression and H3K4me3 enrichments of key defence genes using qPCR and ChIP-qPCR. Salicylic acid (SA) and pipecolic acid (Pip) levels were quantified and function of JMJ14 in SA- and Pip-mediated defences was analysed in Col-0 and jmj14 plants. jmj14 mutants were compromised in both local and systemic defences. JMJ14 positively regulates pathogen-induced H3K4me3 enrichment and expression of defence genes involved in SA- and Pip-mediated defence pathways. Consequently, loss of JMJ14 results in attenuated defence gene expression and reduced Pip accumulation during establishment of systemic acquired resistance (SAR). Exogenous Pip partially restored SAR in jmj14 plants, suggesting that JMJ14 regulated Pip biosynthesis and other downstream factors regulate SAR in jmj14 plants. JMJ14 positively modulates defence gene expressions and Pip levels in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Histona Desmetilases com o Domínio Jumonji , Ácidos Pipecólicos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Doenças das Plantas/genética , Imunidade Vegetal , Ácido Salicílico/farmacologia
10.
Biol Lett ; 16(4): 20190940, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32343935

RESUMO

Geomagnetic field (GMF) intensity can be used by some animals to determine their position during migration. However, its role, if any, in mediating other migration-related phenotypes remains largely unknown. Here, we simulated variation in GMF intensity between two locations along the migration route of a nocturnal insect migrant, the brown planthopper Nilaparvata lugens, that varied by approximately 5 µT in field intensity. After one generation of exposure, we tested for changes in key morphological, behavioural and physiological traits related to migratory performance, including wing dimorphism, flight capacity and positive phototaxis. Our results showed that all three morphological and behavioural phenotypes responded to a small difference in magnetic field intensity. Consistent magnetic responses in the expression of the phototaxis-related Drosophila-like cryptochrome 1 (Cry1) gene and levels of two primary energy substrates used during flight, triglyceride and trehalose, were also found. Our findings indicate changes in GMF intensity can alter the expression of phenotypes critical for insect migration and highlight the unique role of magnetoreception as a trait that may help migratory insects express potentially beneficial phenotypes in geographically variable environments.


Assuntos
Hemípteros , Animais , Hemípteros/genética , Proteínas de Insetos/genética , Campos Magnéticos , Fenótipo , Asas de Animais
11.
Entropy (Basel) ; 22(2)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33285997

RESUMO

Since the cloud radio access network (C-RAN) transmits information signals by jointly transmission, the multiple copies of information signals might be eavesdropped on. Therefore, this paper studies the resource allocation algorithm for secure energy optimization in a downlink C-RAN, via jointly designing base station (BS) mode, beamforming and artificial noise (AN) given imperfect channel state information (CSI) of information receivers (IRs) and eavesdrop receivers (ERs). The considered resource allocation design problem is formulated as a nonlinear programming problem of power minimization under the quality of service (QoS) for each IR, the power constraint for each BS, and the physical layer security (PLS) constraints for each ER. To solve this non-trivial problem, we first adopt smooth ℓ 0 -norm approximation and propose a general iterative difference of convex (IDC) algorithm with provable convergence for a difference of convex programming problem. Then, a three-stage algorithm is proposed to solve the original problem, which firstly apply the iterative difference of convex programming with semi-definite relaxation (SDR) technique to provide a roughly (approximately) sparse solution, and then improve the sparsity of the solutions using a deflation based post processing method. The effectiveness of the proposed algorithm is validated with extensive simulations for power minimization in secure downlink C-RANs.

12.
Genome ; 62(9): 597-608, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31271724

RESUMO

The hormone auxin is involved in many biological processes throughout a plant's lifecycle. However, genes in the GH3 (Gretchen Hagen3) family, one of the three major auxin-responsive gene families, have not yet been identified in oilseed rape (Brassica napus). In this study, we identified 63 BnaGH3 genes in oilseed rape using homology searches. We analyzed the chromosome locations, gene structures, and phylogenetic relationships of the BnaGH3 genes, as well as the cis-elements in their promoters. Most BnaGH3 genes are located on chromosomes A03, A09, C02, C03, and C09, each with 4-7 members. In addition, we analyzed the expression patterns of BnaGH3 genes in seven tissues by transcriptome sequencing and quantitative RT-PCR analysis of plants under exogenous IAA treatment. The BnaGH3 genes showed different expression patterns in various tissues. BnaA.GH3.2-1 and BnaC.GH3.2-1 were expressed in the seed and seed coat during development and in response to IAA treatment. These results shed light on the possible roles of the GH3 gene family in oilseed rape.


Assuntos
Brassica napus/genética , Genoma de Planta , Mapeamento Cromossômico , Cromossomos de Plantas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Família Multigênica , Sequências Reguladoras de Ácido Nucleico
13.
Zhongguo Zhong Yao Za Zhi ; 43(10): 2129-2133, 2018 May.
Artigo em Chinês | MEDLINE | ID: mdl-29933682

RESUMO

The type 2 diabetes rat model was induced with high-sugar and high-fat diet combined with low-dose STZ. This study investigated the hypolipidemic mechanism of Coptis chinensis and C. deltoidea. After 30 days of administration, HOMA-IR and the content of TG in serum were detected, and the expressions of SCAP, SREBP-1c were tested by the method of Western blot and Real-time PCR analysis. The test results showed that both components can significantly alleviate insulin resistance and down-regulate the expressions of SREBP-1c and SCAP in liver tissue of type two diabetes mellitus. Compared with the control group, there were significant differences in relevant protein expression (P<0.05, P<0.01). This indicates that the inhibition of SREBP-1c and SCAP expressions may be the hypolipidemic mechanism of Coptidis Rhizoma on type 2 diabetes mellitus. The results also showed that C. deltoidea has a better efficacy in lipid elimination, but a weaker hypoglycemic effect against C. chinensis.


Assuntos
Coptis/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Transdução de Sinais , Animais , Coptis/classificação , Diabetes Mellitus Experimental/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Ratos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
14.
Zhongguo Zhong Yao Za Zhi ; 42(7): 1395-1400, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29052405

RESUMO

Artemisia hedinii occupies an important position in the Tibetan medicine. Plants in Artemisia vary a lot and are widely distributed in the Qinghai-Tibet Plateau, many plants in Artemisia look similar, making traditional identification methods laborious. In this article, ITS2 sequences were used as DNA barcoding to identify four kinds of confusable Tibetan medicine plants in Artemisia, aiming to establish a rapid and accurate identification methods. Twenty-one samples in Artemisia were collected from the Qinghai-Tibet Plateau, ITS2 sequence PCR amplification and sequencing were conducted after the extraction of DNA. Another 11 sequence downloaded from Genbank were added to the analysis. Genetic distance calculation and analysis, building Neighbor Joining (NJ) phylogenetic tree were conducted by MEGA 6.0, also comparison of secondary structures of ITS2 sequences among samples. A. hedinii, A. annua, A. dubia and A. argyi shared close genetic distance, but the maximum distance between the four species was much greater than the minimum distance within each species, NJ tree showed that the four species went to four separate branches, differences among secondary structures of ITS2 sequences also made it clear to identify these medical plants. It could be an accurate and rapid method for identification and recognition, as well as the evolutionary relationships between the species by using ITS2 sequence as DNA barcode for plants of Tibetan Artemisia. The study provides theoretical basis for quality control, medication safety and rational exploitation.


Assuntos
Artemisia/genética , Código de Barras de DNA Taxonômico , DNA Espaçador Ribossômico/genética , Filogenia , DNA de Plantas/genética , Plantas Medicinais/genética , Tibet
15.
Zhongguo Zhong Yao Za Zhi ; 40(13): 2674-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26697698

RESUMO

The study focused on the therapeutic efficacy of Tibetan medicines on cerebral ischemia. The combined medication methods and administration habits in clinic for more than 10 years were simulated. Three typical Tibetan medicines, i.e., 25-Herb Shanhu pill, Wishful-Treasure pill and 20-Herb Chenxiang pill, were administered to the animal model of permanent middle cerebral artery occlusion in the morning, noon and evening, respectively. On the second day after the final administration, the activity of serum oxidative stress marker SOD and the content of MDA were evaluated. Infarct volumes were quantified through TTC staining. Inflammatory reaction maker NF-kappaB p65 gene and apoptosis. makers Bax and Cyct were selected to study the molecular mechanism of combined herbs with the immunohistochemistry technique. According to the result, the respective combination of 25-Herb Shanhu pill, Wishful-Treasure pill and 20-Herb Chenxiang pill in the morning, noon and evening showed unique advantages in reducing the damage of oxidative stress, infarct volumes, encephaledema caused by ischemia, inflammatory factor aggregation and inhibiting apoptosis, with consistent therapeutic efficacies in clinic.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Medicina Tradicional Tibetana , Animais , Isquemia Encefálica/metabolismo , Peroxidação de Lipídeos , Masculino , Ratos , Superóxido Dismutase/metabolismo , Fatores de Tempo , Fator de Transcrição RelA/fisiologia
16.
Zhongguo Zhong Yao Za Zhi ; 40(3): 556-9, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26084187

RESUMO

Ischemic stroke is a primary cause of death and long-term disability all over the world. This disease is resulted from ischemia and hypoxia in brain tissues because of insufficient blood supply and causes a series of physiochemical metabolism disorders and physiological dysfunction. Its high disability ratio has bright huge burdens to society, governments and families. However, there is not efficacious medicine to treat it. In this study, a right middle cerebral artery occlusion was established in rats to observe the multi-path and multi-aspect intervention effects of Tibetan patent medicine Ruyi Zhenbao pills in reducing injuries to Nissl bodies, cerebral edema and inflammatory reactions and preventing cellular apoptosis, in order to lay a foundation for defining its therapeutic mechanism in acute ischemic stroke.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Medicina Tradicional Tibetana , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Masculino , Medicina Tradicional Chinesa , NF-kappa B/fisiologia , Patentes como Assunto , Ratos , Ratos Sprague-Dawley
17.
Bioorg Med Chem Lett ; 24(2): 679-84, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24365157

RESUMO

Tumor angiogenesis is a complicated process based upon a sequence of interactions between tumor and vessel endothelial cells. Tumor conditioned medium has been widely used to stimulate endothelial cells in vitro angiogenesis. This work was aimed to investigate the effects of gold nanoparticles (GNPs) on angiogenesis in hepatic carcinoma-conditioned endothelial cells. Human umbilical vein endothelial cells (HUVECs) were cultured with conditioned medium (CM) from the human hepatocarcinoma cell line HepG2 (HepG2-CM), and then treated with different concentrations of GNPs. The effects of GNPs on the viability, migration and active VEGF level of HUVECs were investigated by MTT assay, wound healing assay and transwell chamber assay, and ELISA assay, respectively. The data showed that GNPs significantly inhibited HUVECs proliferation and migration induced by HepG2-CM, and also reduced the levels of active VEGF in the co-culture system. Then, the alterations in morphology and ultrastructure of HUVECs detected by atomic force microscopy (AFM) showed that there appeared obvious pseudopodia, larger membrane particle sizes and much rougher surface in HUVECs after HepG2-CM treatment, which were all reversed after GNPs treatment. Changes in cytoskeleton of HUVECs determined by immunocytochemistry demonstrated that GNPs treatment remarkably inhibited the activation effect of HepG2-CM on HUVECs, which was associated with the disruption of actin filaments induced by GNPs. This study indicates that GNPs can significantly inhibit HepG2-CM activated endothelial cell proliferation and migration through down-regulation of VEGF activity and disruption of cell morphology, revealing the potential applications of GNPs as antiangiogenic agent for the treatment of hepatic carcinoma.


Assuntos
Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ouro/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Neoplasias Hepáticas Experimentais , Nanopartículas Metálicas , Animais , Movimento Celular/fisiologia , Técnicas de Cocultura/métodos , Ouro/uso terapêutico , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Neoplasias Hepáticas Experimentais/patologia
18.
Cell Rep ; 43(4): 114051, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38564334

RESUMO

Uropathogenic Escherichia coli (UPEC) is the most common causative agent of urinary tract infection (UTI). UPEC invades bladder epithelial cells (BECs) via fusiform vesicles, escapes into the cytosol, and establishes biofilm-like intracellular bacterial communities (IBCs). Nucleoside-diphosphate kinase (NDK) is secreted by pathogenic bacteria to enhance virulence. However, whether NDK is involved in UPEC pathogenesis remains unclear. Here, we find that the lack of ndk impairs the colonization of UPEC CFT073 in mouse bladders and kidneys owing to the impaired ability of UPEC to form IBCs. Furthermore, we demonstrate that NDK inhibits caspase-1-dependent pyroptosis by consuming extracellular ATP, preventing superficial BEC exfoliation, and promoting IBC formation. UPEC utilizes the reactive oxygen species (ROS) sensor OxyR to indirectly activate the regulator integration host factor, which then directly activates ndk expression in response to intracellular ROS. Here, we reveal a signaling transduction pathway that UPEC employs to inhibit superficial BEC exfoliation, thus facilitating acute UTI.


Assuntos
Caspase 1 , Infecções por Escherichia coli , Núcleosídeo-Difosfato Quinase , Piroptose , Infecções Urinárias , Escherichia coli Uropatogênica , Escherichia coli Uropatogênica/patogenicidade , Animais , Infecções Urinárias/microbiologia , Infecções Urinárias/patologia , Camundongos , Caspase 1/metabolismo , Núcleosídeo-Difosfato Quinase/metabolismo , Núcleosídeo-Difosfato Quinase/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/patologia , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos C57BL , Humanos , Feminino , Bexiga Urinária/microbiologia , Bexiga Urinária/patologia , Células Epiteliais/microbiologia , Células Epiteliais/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Transdução de Sinais
19.
Int J Biol Macromol ; 276(Pt 1): 133792, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992539

RESUMO

Doxorubicin (Dox), a chemotherapeutic agent frequently used to treat cancer, elicits cardiotoxicity, a condition referred to as Dox-induced cardiotoxicity (DIC), and ferroptosis plays a contributory role in its pathophysiology. Fucoidan, a polysaccharide with various biological activities and safety profile, has potential therapeutic and pharmaceutical applications. This study aimed to investigate the protective effects and underlying mechanisms of fucoidan in DIC. Echocardiography, biomarkers of cardiomyocyte injury, serum creatine kinase, creatine kinase isoenzyme and lactate dehydrogenase, as well as histological staining results, revealed that fucoidan significantly reduced myocardial damage and improved cardiac function in DIC mice. Transmission electron microscopy; levels of lipid reactive oxygen species, glutathione, and malondialdehyde; ferroptosis-related markers; and regulatory factors such as glutathione peroxidase 4 (GPX4), transferrin receptor protein-1, ferritin heavy chain-1, heme oxygenase-1 in the heart tissue were measured to explore the effect of fucoidan on Dox-induced ferroptosis. These results suggested that fucoidan could inhibit cardiomyocyte ferroptosis caused by Dox. In vitro experiments revealed that silencing nuclear factor-erythroid 2-related factor 2 (Nrf2) in cardiomyocytes reduced the inhibitory effect of fucoidan on ferroptosis. Hence, fucoidan has the potential to ameliorate DIC by inhibiting ferroptosis via the Nrf2/GPX4 pathway.

20.
Front Endocrinol (Lausanne) ; 15: 1338465, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495785

RESUMO

Objective: Multiple observational studies have demonstrated an association between type 2 diabetes mellitus (T2DM) and chronic liver diseases (CLDs). However, the causality of T2DM on CLDs remained unknown in various ethnic groups. Methods: We obtained instrumental variables for T2DM and conducted a two-sample mendelian randomization (MR) study to examine the causal effect on nonalcoholic fatty liver disease (NAFLD), hepatocellular carcinoma (HCC), viral hepatitis, hepatitis B virus (HBV) infection, and hepatitis C virus (HCV) infection risk in Europeans and East Asians. The primary analysis utilized the inverse variance weighting (IVW) technique to evaluate the causal relationship between T2DM and CLDs. In addition, we conducted a series of rigorous analyses to bolster the reliability of our MR results. Results: In Europeans, we found that genetic liability to T2DM has been linked with increased risk of NAFLD (IVW : OR =1.3654, 95% confidence interval [CI], 1.2250-1.5219, p=1.85e-8), viral hepatitis (IVW : OR =1.1173, 95%CI, 1.0271-1.2154, p=0.0098), and a suggestive positive association between T2DM and HCC (IVW : OR=1.2671, 95%CI, 1.0471-1.5333, p=0.0150), HBV (IVW : OR=1.1908, 95% CI, 1.0368-1.3677, p=0.0134). No causal association between T2DM and HCV was discovered. Among East Asians, however, there was a significant inverse association between T2DM and the proxies of NAFLD (ALT: IVW OR=0.9752, 95%CI 0.9597-0.9909, p=0.0021; AST: IVW OR=0.9673, 95%CI, 0.9528-0.9821, p=1.67e-5), and HCV (IVW: OR=0.9289, 95%CI, 0.8852-0.9747, p=0.0027). Notably, no causal association was found between T2DM and HCC, viral hepatitis, or HBV. Conclusion: Our MR analysis revealed varying causal associations between T2DM and CLDs in East Asians and Europeans. Further research is required to investigate the potential mechanisms in various ethnic groups, which could yield new insights into early screening and prevention strategies for CLDs in T2DM patients.


Assuntos
Carcinoma Hepatocelular , Diabetes Mellitus Tipo 2 , Hepatite B , Hepatite C , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/genética , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/genética , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Reprodutibilidade dos Testes , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/genética , Hepacivirus
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