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1.
Stress Biol ; 3(1): 17, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37676352

RESUMO

Fasting is a popular dietary strategy because it grants numerous advantages, and redox regulation is one mechanism involved. However, the precise redox changes with respect to the redox species, organelles and tissues remain unclear, which hinders the understanding of the metabolic mechanism, and exploring the precision redox map under various dietary statuses is of great significance. Twelve redox-sensitive C. elegans strains stably expressing genetically encoded redox fluorescent probes (Hyperion sensing H2O2 and Grx1-roGFP2 sensing GSH/GSSG) in three organelles (cytoplasm, mitochondria and endoplasmic reticulum (ER)) were constructed in two tissues (body wall muscle and neurons) and were confirmed to respond to redox challenge. The H2O2 and GSSG/GSH redox changes in two tissues and three organelles were obtained by confocal microscopy during fasting, refeeding, and satiation. We found that under fasting condition, H2O2 decreased in most compartments, except for an increase in mitochondria, while GSSG/GSH increased in the cytoplasm of body muscle and the ER of neurons. After refeeding, the redox changes in H2O2 and GSSG/GSH caused by fasting were reversed in most organelles of the body wall muscle and neurons. In the satiated state, H2O2 increased markedly in the cytoplasm, mitochondria and ER of muscle and the ER of neurons, while GSSG/GSH exhibited no change in most organelles of the two tissues except for an increase in the ER of muscle. Our study systematically and precisely presents the redox characteristics under different dietary states in living animals and provides a basis for further investigating the redox mechanism in metabolism and optimizing dietary guidance.

2.
Comput Intell Neurosci ; 2023: 7064236, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909975

RESUMO

The purpose of this study is to understand the relationship between social capital and the performance of Farmers' Cooperatives (Cooperatives) and explore the internal mechanism of social capital affecting the performance of Cooperatives. This work selects two dimensions: cognitive social capital (CSC) and structural social capital (SSC), as indexes to measure the social capital of Cooperatives. An analytical framework is proposed: "Social capital-Dynamic capabilities-Organizational performance." First, according to the characteristics of Cooperatives, it determines the most appropriate index values and preprocesses the original data. Statistical Product and Service Solutions (SPSS) and Analysis of Moment Structure (AMOS) 25.0 software are used for factor analysis. A financial performance evaluation model of Cooperatives based on backpropagation neural network (BPNN) is constructed. Then, based on the survey data of 212 Cooperatives in Liaoning Province, the structural equation model (SEM) is used to test the interaction path between "Social capital-Dynamic capacity-Organizational performance." The results show that SSC's standardized regression coefficients (SRCs) on Cooperatives' economic benefits and member satisfaction are 0.208 and 0.095, respectively, significant at 1%. The actual case analysis concludes that the larger the scale of the structural network embedded in Cooperatives is, the more conducive it is to obtaining extensive resources. As such, Cooperatives can absorb the advanced experience and compensate for the weakness of lack of internal resources and experience. The SRC of CSC on Cooperatives' economic benefits is 0.336, and the P value is 0.204, indicating an insignificant impact of CSC on Cooperatives' economic benefits. This work considers environmental variability, uses dynamic capacity as an independent variable, opens the "black box" between social capital and the performance of Cooperatives, and reveals the intermediate path between the two.


Assuntos
Aprendizado Profundo , Capital Social , Humanos , Fazendeiros , Inquéritos e Questionários , China
3.
Huan Jing Ke Xue ; 43(8): 4097-4107, 2022 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-35971707

RESUMO

Planktonic microorganisms play an important role in urban aquatic ecosystems; however, environmental changes significantly affect their role in the degradation and transformation of pollutants. The highly artificial North Canal River was chosen as the research area in this study. Seasonal changes in planktonic microbial community structure were studied using 16S rRNA high-throughput sequencing. The seasonal change mechanism of planktonic microbial diversity in urban rivers supplied with reclaimed water and its response relationship with environmental parameters were examined. The results showed that there were significant seasonal changes in the diversity and structure of the planktonic microbial community. The alpha diversity in summer was significantly higher than that in spring, owing to the enhancement of water diffusion capacity caused by seasonal rainfall and physical disturbance of the reclaimed water supply. The beta diversity of the planktonic microbial community in summer was weakened compared to that in spring, also owing to the enhancement of water diffusion capacity. Seasonal runoff and temperature were the main driving factors of the seasonal variation in hydrology and water quality in the highly artificial urban river. The changes in NO2--N and TP caused by seasonal runoff and temperature change were the main reason for planktonic microbial diversity changes in the river. The reductive environment of the river was caused by static and discontinuous flow in the spring. Anaerobic bacteria such as Bacteroidetes related to the degradation of dissolved organic matter and Gracilibacteria related to the denitrification process were dominant in the river. Seasonal runoff and frequent rainfall in summer, as well as the increase in the opening and closing frequency of river sluice gates, enhanced the reoxygenation capacity of the river. This significantly alleviated nutrient pollution in the North River Cannel. Additionally, aerobic bacteria and facultative anaerobic bacteria were dominant species in the river during spring. Cyanobacteria with high temperature characteristics, Chloroflexi and other autotrophic microorganisms, as well as Acidobacteria and Gemmatimonadetes played an important role in the degradation and transformation of pollutants. The results of this study have practical significance for urban river pollution control and ecological restoration with reclaimed water as the recharge water source.


Assuntos
Poluentes Ambientais , Microbiota , Bactérias/genética , Plâncton , RNA Ribossômico 16S/genética , Rios/química , Estações do Ano , Qualidade da Água
4.
Free Radic Biol Med ; 180: 165-178, 2022 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-35033630

RESUMO

Oxidative stress in aging has attracted much attention; however, the role of reductive stress in aging remains largely unknown. Here, we report that the endoplasmic reticulum (ER) undergoes reductive stress during replicative senescence, as shown by specific glutathione and H2O2 fluorescent probes. We constructed an ER-specific reductive stress cell model by ER-specific catalase overexpression and observed accelerated senescent phenotypes accompanied by disrupted proteostasis and a compromised ER unfolded protein response (UPR). Mechanistically, S-nitrosation of the pivotal ER sulfhydryl oxidase Ero1α led to decreased activity, therefore resulting in reductive stress in the ER. Inhibition of inducible nitric oxide synthase decreased the level of Ero1α S-nitrosation and decreased cellular senescence. Moreover, the expression of constitutively active Ero1α restored an oxidizing state in the ER and successfully rescued the senescent phenotypes. Our results uncover a new mechanism of senescence promoted by ER reductive stress and provide proof-of-concept that maintaining the oxidizing power of the ER and organelle-specific precision redox regulation could be valuable future geroprotective strategies.


Assuntos
Estresse do Retículo Endoplasmático , Peróxido de Hidrogênio , Senescência Celular , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/genética , Peróxido de Hidrogênio/metabolismo , Nitrosação , Resposta a Proteínas não Dobradas
5.
Immunol Lett ; 214: 37-44, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31473255

RESUMO

Oral tolerance, induced by oral administration of autoantigens, is a promising therapeutic approach to treat type 1 diabetes mellitus (T1DM). However, the degradation of antigens passing through the gastrointestinal tract (GIT) leads to low induction efficiency. Based on our previous study, a single-chain insulin (SCI-59) analog, bound to the surface of lactic acid bacteria (LAB) bacterium-like particles (BLPs), was more stable in the simulated gastric fluid, compared to free SCI-59 and insulin. Based on the analysis of diabetes progression, a significant decrease in the incidence of diabetes was observed in mice fed BLPs-SCI-59. Oral administration of BLPs-SCI-59 can enhance glucose tolerance in NOD mice and this effect may result from the protection of pancreatic islet beta cells, as compared to the free SCI-59 group and BLPs group. Oral administration of BLPs-SCI-59 can significantly reduce insulitis and preserve the ability of insulin secretion in treated mice. Oral vaccination with BLPs-SCI-59 induced SCI-59 specific T cell tolerance in treated mice, which may due to the repair of Th1/Th2 imbalance and increased CD4+CD25+FoxP3+ regulatory T cells (Tregs). These results show that oral vaccination with BLPs-SCI-59 is a promising way to prevent T1DM in NOD mice.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Tolerância Imunológica/efeitos dos fármacos , Insulina/farmacologia , Lactobacillales , Administração Oral , Animais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/patologia , Insulina/imunologia , Camundongos , Camundongos Endogâmicos NOD , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Células Th1/imunologia , Células Th1/patologia , Células Th2/imunologia , Células Th2/patologia
6.
Chemosphere ; 211: 44-49, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30071435

RESUMO

The low-low temperature electrostatic precipitator (LLT-ESP) is one of the most used devices for pollutant control in ultra-low emission coal-fired power plants. This study investigated the influence of the LLT-ESP on polycyclic aromatic hydrocarbons (PAHs) distributions in flue gas from an ultra-low emission coal-fired power plant. The total gas-phase PAH concentration was reduced from 27.52 µg/m3 to 3.38 µg/m3. The total particulate-phase PAH concentration decreased from 14.36 µg/m3 to 0.34 µg/m3. The removal efficiency of the LLT-ESP for gas-phase and particulate phase carcinogenic higher molecular weight (HMW) PAHs was 85% and 99%, respectively. The total concentration of 16 selected PAHs in feed coal was 98.16 µg/g. The fly ash particle size successively decreased from Electric Field 1 (F1) to Electric Field 4 (F4). The total PAH concentration decreased from F1 to F2 but increased again from F3 to F4. The flue gas cooling process significantly contributed to the elimination of both gas- and particulate-phase PAHs in the flue gas. Presumably, most of the condensed PAHs were adhered to or absorbed in the fly ash and were scavenged in Field 1. Both gas- and particulate-phase 5- and 6-ring PAHs in the flue gas were completely removed in Field 1. The discharge process in the electric fields may promote the formation of several 4- or 5-ring PAHs. In this study, benzo[k]fluoranthene (BKF) and benzo[a]pyrene (BaP) were regenerated in the particles rather than in the flue gas during the discharge process in the electric fields.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/química , Centrais Elétricas/estatística & dados numéricos , Eletricidade Estática , Hidrocarbonetos Policíclicos Aromáticos/análise , Temperatura
7.
Oncotarget ; 8(60): 101309-101324, 2017 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-29254166

RESUMO

In the present study, we found the mRNA expression level of glycerol-3-phosphate dehydrogenase (GPD1) was significantly downregulated in human breast cancer patients. Patients with reduced GPD1 expression exhibited poorer overall metastatic relapse-free survival (p = 0.0013). Further Cox proportional hazard model analysis revealed that the reduced expression of GPD1 is an independent predictor of overall survival in oestrogen receptor-positive (p = 0.0027, HR = 0.91, 95% CI = 0.85-0.97, N = 3,917) and nodal-negative (p = 0.0013, HR = 0.87, 95% CI = 0.80-0.95, N = 2,456) breast cancer patients. We also demonstrated that GPD1 was a direct target of miR-370, which was significantly upregulated in human breast cancer. We further showed that exogenous expression of GPD1 in human MCF-7 and MDA-MB-231 breast cancer cells significantly inhibited cell proliferation, migration, and invasion. Our results, therefore, suggest a novel tumour suppressor function for GPD1 and contribute to the understanding of cancer metabolism.

8.
Appl Microbiol Biotechnol ; 101(8): 3259-3271, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28120013

RESUMO

Insulin plays an important role in drug therapies for diabetes mellitus and as the main route of insulin delivery, subcutaneous injection may cause local discomfort, hypoglycemia, hyperinsulinemia, and patient non-compliance. Therefore, oral delivery of insulin is more preferred. However, there is a low bioavailability due to insulin degradation by proteolytic enzymes and severe pH conditions along the gastrointestinal tract. In order to use the food-grade bacteria lactic acid bacteria (LAB) as oral delivery vehicles, a new and bioactive single-chain insulin (SCI-59) analog, containing the insulin B- and A-chains connected by an eight-residue linker (RSRGLPFR), was secretory expressed in Lactococcus lactis NZ3900 without using an antibiotic resistance gene and displayed onto the surface of various non-viable bacteria (NVBs) without genetic modification. Both the free SCI-59 and SCI-59 displayed on the surface of NVBs are biologically active as assayed by their ability to stimulate Akt signaling in differentiated 3T3-L1 adipocytes. Modification of the pH of the medium by NaOH addition at early time during induction can enhance the bioactivity of SCI-59. The C-terminal fused anchoring domain, three LysM repeats, does not affect the formation of disulfide bonds and/or the folding of SCI-59, and SCI-59 could be exposed properly and fully when SCI-59-3LysM bound to the surface of NVBs. Compared to the free form SCI-59, SCI-59 displayed on the surface of NVBs is more stable in simulate gastric juice. It may open new prospects for possible oral treatments of diabetes using live LAB secreting or NVBs carrying bioactive SCI analogs.


Assuntos
Técnicas de Visualização da Superfície Celular/métodos , Insulina/análogos & derivados , Insulina/metabolismo , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Administração Oral , Transporte Biológico , Diabetes Mellitus/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Humanos , Insulina/química , Insulina/genética , Secreção de Insulina , Viabilidade Microbiana , Transdução de Sinais
9.
Appl Microbiol Biotechnol ; 100(22): 9407-9421, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27649963

RESUMO

Microbial cell surface display has attracted greater attention than ever and has numerous potential applications in biotechnology. With the safety and probiotic properties, lactic acid bacteria (LAB) have been used widely in food and industrial applications. In order to circumvent using genetically modified microorganisms which face low public acceptance and severe regulatory scrutiny, surface-engineered LAB without genetical modification are more preferred. According to the way used to obtain the fusion protein containing the passenger molecule and anchoring domain, the genetic or chemical approaches can be used to construct these surface-engineered LAB. In addition to the viable wide-type LAB, non-living bacterial-like particles (BLP) can be attached by these fusion proteins added from outside. Compared to the living LAB, BLP have a higher binding capacity and less anticarrier response. Mucosal vaccines are the predominant application of these surface-engineered LAB with no genetical modification.


Assuntos
Técnicas de Visualização da Superfície Celular/métodos , Lactobacillales/química , Administração através da Mucosa , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/imunologia
10.
Transplantation ; 77(3): 460-2, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14966427

RESUMO

BACKGROUND: The authors previously reported thromboembolic complications associated with anti-CD154 monoclonal antibody (mAb) treatment in nonhuman primates. The underlying mechanisms of this complication and its management have not been established. METHODS: Eighty cynomolgus monkey renal allograft recipients treated with anti-CD154 mAb were studied for the incidence of thrombosis and its prophylaxis. RESULTS: Without anticoagulation prophylaxis, thromboembolic complications were seen in 5 of 11 recipients. With addition of perioperative heparin, the incidence was decreased to 2 of 10. No further improvement was observed by adding intraoperative prostaglandin (PG) E1. However, addition of ketorolac tromethamine to PGE1 and heparin decreased the incidence of thrombosis (one of eight). Most recently, the authors have found that ketorolac administration alone resulted in no thrombosis in 25 consecutive recipients. CONCLUSIONS: Ketorolac is remarkably effective in preventing thromboembolism associated with anti-CD154 mAb treatment, suggesting the mechanism underlying this complication may be related to platelet activation leading to enhanced aggregation.


Assuntos
Anticorpos Monoclonais/imunologia , Ligante de CD40/imunologia , Transplante de Rim , Trombofilia/imunologia , Trombofilia/prevenção & controle , Alprostadil/farmacologia , Animais , Anticoagulantes/farmacologia , Combinação de Medicamentos , Heparina/farmacologia , Incidência , Cetorolaco de Trometamina/farmacologia , Macaca fascicularis , Inibidores da Agregação Plaquetária/farmacologia , Trombofilia/epidemiologia , Transplante Homólogo
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