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1.
Anim Biosci ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38938027

RESUMO

Objective: The objective of this study was to reveal the influence of acute and chronic heat stress (HS) on the abundance and function of rumen microbiome and host metabolism. Methods: The forty mid-lactation goats were randomly divided into two artificial environments a control group and a heat-stressed group. This study was collected from two periods, 1 day and 28 days. The first day was defined as control 1 (CT1) and HS 1 (acute HS), and the last day was defined as CT28 and HS28 (chronic HS). On the first and last day, 6 dairy goats in each group were randomly selected to collect rumen liquid after the morning feeding through oral stomach tubes. The barn temperature and humidity were recorded every day. Results: Disruption of the rumen microbiome was observed under chronic HS, represented by an increase in the abundance of Prevotella and Bacteroidales (p<0.05), and upregulation of carbohydrate transport and metabolism functions (p<0.05). Additionally, the abundance of Succinimonas and Ruminobacter in chronic HS is lower than in acute HS (p<0.05), and the functions of intracellular trafficking, secretion and vesicular transport, and the cytoskeleton were downregulated (p<0.05). Conclusion: HS affected the interaction between the microbiota and host, thereby regulating milk production in dairy goats. These findings increased understanding of the crosstalk between hosts and microorganisms.

2.
Sci Data ; 11(1): 288, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472222

RESUMO

Application of high-throughput sequencing and screening help to detect the transcriptional and metabolic discrepancies in organs provided with various levels of nutrients. The influences of individual essential amino acid (EAA) administration on transcriptomic and metabolomic profilings of bovine mammary epithelial cells (BMECs) were systematically investigated. A RNA sequencing and liquid chromatography-tandem mass spectrometry generated a comprehensive comparison of transcriptomics, non-targeted metabolomics and targeted amino acids profilings of BMECs with individual EAA stimulation by turn. The sequencing data and raw LC-MS/MS data of samples were presented in the databases of Gene Expression Omnibus, MetaboLights and Figshare for efficient reuse, including exploring the divergences in metabolisms between different EAAs and screening valuable genes and metabolites regulating casein synthesis.


Assuntos
Aminoácidos Essenciais , Células Epiteliais , Multiômica , Animais , Bovinos , Aminoácidos Essenciais/metabolismo , Cromatografia Líquida , Células Epiteliais/metabolismo , Metabolômica , Espectrometria de Massas em Tandem , Glândulas Mamárias Animais/citologia
3.
Poult Sci ; 103(2): 103274, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043405

RESUMO

This study aimed to determine the effects of chlorogenic acid (CGA) on the growth performance, intestinal health, immune response, and mitochondrial DNA (mtDNA)-cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway in broilers under necrotic enteritis (NE) challenge. The 180 one-day-old male Cobb 500 broilers with similar body weight of 44.59 ± 1.39 g were randomly allocated into 3 groups. The groups were control diet (Control group), control diet + NE challenge (NE group), and control diet + 500 mg/kg CGA + NE challenge (NE + CGA group), with 6 replicates per treatment. All broilers except the Control group were given sporulated coccidian oocysts (d 14) and Clostridium perfringens (d 19-21) by oral gavage. Our findings showed that CGA improved the growth performance and intestinal morphology in broilers under NE challenge. CGA supplementation elevated the barrier function in broilers under NE challenge, which reflected in the decreased serum concentrations of D-lactate and diamine oxidase, and upregulated jejunal protein expression of occludin. CGA supplementation also improved the immune function, which reflected in the increased concentrations and gene expressions of anti-inflammatory factors, and decreased concentrations and gene expressions of proinflammatory factors. CGA supplementation further enhanced intestinal cell proliferation and differentiation, which manifested in the increased number of goblet cells and positive cells of proliferating cell nuclear antigen on d 28 and 42. Furthermore, CGA supplementation decreased the mtDNA (d 42) and mitochondrial reactive oxygen species levels (d 28 and 42), and increased the mitochondrial membrane potential (d 42) and mitochondrial complex I (d 28 and 42) or III (d 28) activity. Broilers challenged with NE had upregulated jejunal protein expressions of cGAS, phospho-TANK-binding kinase 1, and phospho-interferon regulatory factor 7 compared with the Control group, which were downregulated after CGA supplementation. In conclusion, dietary supplementation CGA could protect against intestinal inflammation and injury by reducing the leakage of mtDNA and inactivating the cGAS-STING signaling pathway in broilers under NE challenge.


Assuntos
Infecções por Clostridium , Enterite , Masculino , Animais , Enterite/prevenção & controle , Enterite/veterinária , Galinhas , Ácido Clorogênico , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , DNA Mitocondrial , Transdução de Sinais , Inflamação/prevenção & controle , Inflamação/veterinária , Ração Animal/análise
4.
Small ; 20(11): e2305889, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939307

RESUMO

The development of highly active and acid-stable electrocatalysts for oxygen evolution reaction (OER) is of great significance for water electrolysis technology. Herein, a highly efficient molybdenum-doped mesoporous ruthenium dioxide sphere (Mo-RuO2 ) catalyst is fabricated by a facile impregnation and post-calcination method using mesoporous carbon spheres to template the mesostructure. The optimal Mo0.15 -RuO2 catalyst with Mo doping amount of 15 mol.% exhibits a significantly low overpotential of 147 mV at 10 mA cm-2 , a small Tafel slope of 38 mV decade-1 , and enhanced electrochemical stability in acidic electrolyte, far superior to the commercial RuO2 catalyst. The experimental results and theoretical analysis reveal that the remarkable electrocatalytic performance can be attributed to the large surface area of the mesoporous spherical structure, the structural robustness of the interconnected mesoporous framework, and the change in the electronic structure of Ru active sites induced by Mo doping. These excellent advantages make Mo-doped mesoporous RuO2 spheres a promising catalyst for highly efficient electrocatalytic OER in acidic media.

5.
Small ; 20(15): e2307743, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009525

RESUMO

Herein, a series of imine-linked covalent organic frameworks (COFs) are developed with advanced ordered mesoporous hollow spherical nanomorphology and ultra-large mesopores (4.6 nm in size), named OMHS-COF-M (M = H, Co, and Ni). The ordered mesoporous hollow spherical nanomorphology is revealed to be formed via an Ostwald ripening mechanism based on a one-step self-templated strategy. Encouraged by its unique structural features and outstanding photoelectrical property, the OMHS-COF-Co material is applied as the photocatalyst for CO2-to-CO reduction. Remarkably, it delivers an impressive CO production rate as high as 15 874 µmol g-1 h-1, a large selectivity of 92.4%, and a preeminent cycling stability. From in/ex situ experiments and density functional theory (DFT) calculations, the excellent CO2 photoreduction performance is ascribed to the desirable cooperation of unique ordered mesoporous hollow spherical host and abundant isolated Co active sites, enhancing CO2 activation, and improving electron transfer kinetics as well as reducing the energy barriers for intermediates *COOH generation and CO desorption.

6.
Nutrients ; 15(18)2023 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-37764809

RESUMO

In order to investigate the chronic effects of basic amino acids (BAA) on ß-cell metabolism and insulin secretion, INS-1 ß-cells were randomly assigned to cultures in standard medium (Con), standard medium plus 10 mM L-Arginine (Arg), standard medium plus 10 mM L-Histidine (His) or standard medium plus 10 mM L-Lysine (Lys) for 24 h. Results showed that insulin secretion was decreased by the Arg treatment but was increased by the His treatment relative to the Con group (p < 0.05). Higher BAA concentrations reduced the high glucose-stimulated insulin secretions (p < 0.001), but only Lys treatment increased the intracellular insulin content than that in the Con group (p < 0.05). Compared with Arg and Lys, the His treatment increased the mitochondrial key enzyme gene expressions including Cs, mt-Atp6, mt-Nd4l and Ogdh, and caused a greater change in the metabolites profiling (p < 0.05). The most significant pathways affected by Arg, His and Lys were arginine and proline metabolism, aminoacyl-tRNA biosynthesis and pyrimidine metabolism, respectively. Regression analysis screened 7 genes and 9 metabolites associated with insulin releases during BAA stimulations (p < 0.05). Together, different BAAs exerted dissimilar effects on ß-cell metabolism and insulin outputs.

7.
J Colloid Interface Sci ; 631(Pt A): 96-101, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36370498

RESUMO

Recently, Ni, N-doped carbon (NiNC) electrocatalysts synthesized using metal-organic frameworks (MOFs) as templates have demonstrated attractive catalytic performances in the CO2 reduction reaction (CO2RR). However, most of the reported preparations of MOFs-based precursors are carried out in organic solvents, and the resulting NiNC materials have relatively low metal loadings and mainly exhibit microporous structures, which is unfavorable for the mass transport. Herein, Ni, N-doped meso-microporous carbon electrocatalysts with a range of Ni loadings (M-NiNCx/CNTs) were prepared by the pyrolysis of MOFs-based precursors synthesized in aqueous solution using the surfactant cetyltrimethylammonium bromide (CTAB) as a modifier to promote the adsorption of Ni2+ ions and the formation of mesopores. Owing to the unique morphology, porous structure and high contents of Ni-Nx sites and pyrrolic-N, the optimal catalyst (M-NiNC2/CNTs) shows superior electrocatalytic activity for the CO2RR with a maximum CO Faradaic efficiency (FECO) of 98 % at -0.7 V vs. reversible hydrogen electrode (RHE), and the FECO can reach over 80 % in a wide potential range of -0.5 to -1.0 V vs. RHE. This work develops a facile and environmentally friendly strategy to obtain high-performance and low-cost transition metal-nitrogen-doped porous carbon electrocatalysts for the CO2RR.

8.
Clin Nutr ; 41(7): 1512-1522, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35667267

RESUMO

BACKGROUND & AIMS: Previous research established that the availability of l-arginine affects placental vascular development and fetal growth. However, practical details associated with the effects of l-arginine supplementation on the neonatal outcomes of hypertensive disorder (HD) and intrauterine growth restriction (IUGR) pregnancies are limited. METHODS: The PubMed, ScienceDirect, and Web of Science databases were searched for peer-reviewed literature published by September 30, 2021 to investigate the operational details of l-arginine supplementation in improving neonatal outcomes in complicated pregnancies. Standardized mean difference (SMD) and weighted mean difference (WMD) of continuous variables, as well as the risk ratio (RR) for categorical variables were pooled by random-effects models. RESULTS: The results indicated that l-arginine supplementation increased the plasma nitric oxide (NO) concentrations in IUGR pregnancies (SMD: 0.71; 95% CI: 0.45, 0.97; I2 = 0%), but decreased the risk of preeclampsia in HD mothers (RR: 0.49; 95% CI: 0.31, 0.76; I2 = 0%). Administration with l-arginine elevated birth weights both in hypertensive and IUGR pregnant women, with WMDs of 194.70 g (95% CI: 58.21, 331.20; I2 = 44.2%) and 134.00 g (95% CI: 43.53, 224.46; I2 = 42.4%), respectively. However, the intervention had no effect on gestational age except in HD pregnancies (WMD: 7.05 d; 95% CI: 3.16, 10.95; I2 = 36.5%). l-arginine administration during pregnancy significantly reduced the small for gestational age (SGA) risk of fetus both in HD (RR: 0.51; 95% CI: 0.31, 0.83; I2 = 0.0%) and IUGR mothers (RR: 0.46; 95% CI: 0.25, 0.88; I2 = 0.0%). Subgroup analyses revealed that l-arginine supplementation at <4 g/d dosage or for ≥1-month duration or in the third trimester had a greater effect on birth weights in HD women without proteinuria, but a higher l-arginine dosage was more beneficial for extending gestational age and reducing the risk of SGA in older pregnancies. Additionally, intravenous infusion of l-arginine, but not oral administration, significantly increased birth weight in IUGR pregnancies with elevated NO concentrations, although the recommended amount should be confined to <4 g/d. CONCLUSIONS: These findings provide practical guidelines for l-arginine supplementation to improve the birth outcomes of complicated pregnancies. REGISTRY NUMBER: CRD42021246290 (https://www.crd.york.ac.uk/PROSPERO).


Assuntos
Hipertensão , Complicações na Gravidez , Idoso , Arginina , Peso ao Nascer , Suplementos Nutricionais , Feminino , Retardo do Crescimento Fetal/tratamento farmacológico , Humanos , Recém-Nascido , Óxido Nítrico , Placenta , Gravidez , Resultado da Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Nanoscale ; 14(25): 9104-9111, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35718937

RESUMO

Developing an effective way to synthesize uniform ordered mesoporous metal spheres with controllable diameter is important for enhancing their performance in various applications but remains a challenge. Herein, a one-step and facile Pd2+-assisted soft-templating strategy is reported to synthesize ordered mesoporous Ni spheres (OMNiS) with highly uniform and tunable diameters. In this synthesis methodology, lyotropic liquid crystals (LLCs) are used as a meso-structural template and Pd nuclei obtained from the reduction of Pd2+ ions are used as nucleation sites for directing Ni deposition. The OMNiS samples with average sphere diameter ranging from 50 nm to 190 nm are produced by varying the amount of Pd2+ in the LLC precursor, revealing that the Pd nuclei play a key role in improving the uniformity of the mesoporous Ni spheres and adjusting the sphere diameter. The satisfactory combination of uniform sphere size, high surface area, great conductivity, and highly ordered mesoporous structure for the optimal OMNiS-100 sample contributes to its superior electrocatalytic activity for the oxygen evolution reaction (OER) in an alkaline electrolyte with a low overpotential of 271 mV to drive a current density of 10 mA cm-2, which is much smaller than that of RuO2 (368 mV), along with a remarkable durability.

10.
Sci Data ; 9(1): 299, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701423

RESUMO

Application of mass spectrometry enables the detection of metabolic differences between organisms with different nutritional settings. Divergence in the metabolic fingerprints of rat pancreatic INS-1 ß-cells were systematically captured with regard to ten individual essential amino acid (EAA) availability. A high-resolution tandem mass spectrometry system coupled to liquid chromatography produced a horizontal comparison of metabolic profilings of ß-cells with individual EAA elevated to 10 mmol/L by turn or removal individual EAA from the medium one by one. Quality control samples were injected at regular intervals throughout the analytical run to monitor and evaluate the stability of the system. The raw data of samples and reference compounds including study protocols have been deposited in the open metabolomics database MetaboLights to enable efficient reuse of the datasets, such as investigating the difference in metabolic process between diverse EAAs as well as screening and verifying potential metabolites affecting insulin secretion and ß-cell function.


Assuntos
Aminoácidos Essenciais , Células Secretoras de Insulina , Metabolômica , Animais , Linhagem Celular , Cromatografia Líquida/métodos , Ratos , Espectrometria de Massas em Tandem
11.
Small ; 18(20): e2107997, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35445554

RESUMO

Direct electrochemical conversion of CO2 to CO product powered by renewable electricity is widely advocated as an emerging strategy for alleviating CO2 emissions while addressing global energy issues. However, the development of low-cost and efficient electrocatalysts with high Faradaic efficiency for CO production (FECO ) and high current density remains a grand challenge. Herein, a robust single nickel atomic site electrocatalyst, which features isolated and dense single atomic NiN3 sites anchored on highly defective hierarchically micro-mesoporous carbon (Ni-SAs/HMMNC-800), to enable enhanced charge transport and more exposed active sites for catalyzing electrochemical CO2 -to-CO conversion, is reported. The Ni-SAs/HMMNC-800 catalyst achieves excellent activity and selectivity with high FECO values of >90% throughout a wide potential range (the FECO reaches 99.5% at -0.7 V vs reversible hydrogen electrode) and a CO partial current density as high as 13.0 mA cm-2 at -0.7 V versus reversible hydrogen electrode, as well as a far outstanding durability during long-term continuous operation, indicating a superior CO2 electroreduction performance than that of other reference samples and most of previously reported carbon-based single atom electrocatalysts. Experimental and density functional theory calculations reveal that atomic NiN3 coordination sites coupled adjacent defects are favorable to significantly enhancing the formation of COOH* reaction intermediates while suppressing the competing hydrogen evolution reaction, thereby enhancing the electrocatalytic activity for CO2 -to-CO reduction. Notably, this work provides a valuable new prospect for designing and synthesizing efficient and cost-effective single atom CO2 electroreduction catalysts for practical applications.

12.
FASEB J ; 36(3): e22206, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35199385

RESUMO

Previous work demonstrated that arginine is one of the strongest insulin secretagogues. However, knowledge of the mechanisms linking chronic arginine metabolism with ß-cell function and insulin secretion is relatively limited. After preliminary selection of concentration according to the cell proliferation, the MIN6 pancreatic ß-cells were randomly assigned to culture in 0.04 mM (low-arginine, LA), 0.4 mM (standard-arginine, SA), or 8 mM arginine (high-arginine, HA) for 24 h. Following the treatment, a combination of transcriptomics and metabolomics, together with a series of molecular biological tests were performed to investigate the responses of ß-cells to varied arginine availability. Our results showed that HA treatment reduced the chronic insulin releases, and LA and HA treatments decreased the glucose-stimulated insulin secretions (GSIS) of ß-cells relative to the SA group (p < .05). Transcriptomics analysis indicated that LA administration significantly inhibited oxidative phosphorylation and ATP metabolic process but promoted DNA repair and mRNA processing in ß-cells, while HA administration affected ammonium ion metabolic process and mRNA export (p < .05). Both LA and HA regulated the expressions of genes involved in DNA replication, cell-cycle phase transition, and response to oxidative stress (p < .05). Protein-protein interaction and transcription factor analyses suggested that Trp53 and Nr4a2 genes may play key roles during arginine stimulation. On the contrary, metabolomics analysis demonstrated that the differentially expressed metabolites (DEM) of MIN6 ß-cells induced by LA were mainly enriched in glycerophospholipid metabolism, linoleic acid metabolism, and purine metabolism, while most DEMs between LA vs. SA comparison belonged to amino acid metabolism. When combined the three groups, co-expression analysis suggested that insulin secretions had strong associations with L-pyroglutamic acid, L-glutamate, and creatine concentrations, while intracellular insulin contents were mainly correlated to L-arginine, argininosuccinic acid, and phosphorylcholine. At last, integrated analysis of transcriptomics and metabolomics showed that glycerophospholipid metabolism, biosynthesis of unsaturated fatty acids, and amino acid metabolism were the most relevant pathways in ß-cells exposed to abnormal arginine supply. This descriptive bioinformatics analysis suggested that the disturbed carbohydrate, lipid, and amino acid metabolisms, as well as the increased apoptosis and elevated oxidative stress, contributed to the reduced insulin secretion and lower GSIS in ß-cells induced by LA or HA treatments, while some underlying mechanisms need to be further explored.


Assuntos
Arginina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Metaboloma , Transcriptoma , Animais , Arginina/deficiência , Arginina/farmacologia , Linhagem Celular Tumoral , Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Camundongos
13.
Biomedicines ; 10(1)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35052844

RESUMO

Abnormal arginine metabolism contributes to the development of intrauterine growth restriction (IUGR), preeclampsia (PE), and gestational diabetes mellitus (GDM), which increase the health burden of mothers and induce adverse birth outcomes. However, associations between maternal arginine concentration and different pregnancy complications have not been systematically compared. The PubMed, ScienceDirect, and Web of Science databases were searched for peer-reviewed publications to evaluate the diagnostic value of plasma arginine concentration in complicated pregnancies. Standardized mean difference (SMD) of the arginine concentration was pooled by a random effects model. The results show that increased maternal arginine concentrations were observed in IUGR (SMD: 0.48; 95% CI: 0.20, 0.76; I2 = 47.0%) and GDM (SMD: 0.46; 95% CI: 0.11, 0.81; I2 = 82.3%) cases but not in PE patients (SMD: 0.21; 95% CI: -0.04, 0.47; I2 = 80.3%) compared with the normal cohorts. Subgroup analyses indicated that the non-fasting circulating arginine concentration in third trimester was increased significantly in GDM and severe IUGR pregnancies, but the change mode was dependent on ethnicity. Additionally, only severe PE persons were accompanied by higher plasma arginine concentrations. These findings suggest that maternal arginine concentration is an important reference for assessing the development of pregnancy complications.

14.
Front Nutr ; 9: 1020327, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36741996

RESUMO

Background: Previous studies have demonstrated that diabetes is often accompanied with lower magnesium status. However, practical details regarding the influences of magnesium intervention on hyperglycemia, hypercholesterolemia, and hypertension in type 2 diabetes (T2D) need to be further investigated. Methods: Web of Science, ScienceDirect, and PubMed were searched for relevant literatures published through April 30, 2022, and high-quality data were pooled to evaluate the effects of magnesium supplementation on glycemic, circulating lipids, and blood pressure control in T2D, and to explore the associated practical details. Results: Pooled analyses of 24 randomized controlled trials with 1,325 T2D individuals revealed that subjects who received magnesium supplementation had statistically significant reductions in fasting plasma glucose, glycated hemoglobin, systolic blood pressure and diastolic blood pressure, with WMD values of -0.20 mM (95% CI: -0.30, -0.09), -0.22% (95% CI: -0.41, -0.03), -7.69 mmHg (95% CI: -11.71, -3.66) and -2.71 mmHg (95% CI: -4.02, -1.40), respectively. Detailed subgroup analyses demonstrated that health status of participants including age, body mass index, country, duration of disease, baseline magnesium level and baseline glycemic control condition as well as magnesium formulation, dosage and duration of intervention influenced the effects of magnesium addition. Dose-effect analysis showed that 279 mg/d for 116 d, 429 mg/d for 88 d and 300 mg/d for 120 d are the average optimal dosages and durations for improving glycemic, circulating lipids, and blood pressure controls, respectively. Conclusion: Our findings provide clinically relevant information on the adjuvant therapy of magnesium for improving hyperglycemia, hypercholesterolemia, and hypertension in T2D.

15.
Biology (Basel) ; 10(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34681143

RESUMO

Milk protein (MP) synthesis in the mammary gland of dairy cows is a complex biological process. As the substrates for protein synthesis, amino acids (AAs) are the most important nutrients for milk synthesis. Free AAs (FAAs) are the main precursors of MP synthesis, and their supplies are supplemented by peptide-bound AAs (PBAAs) in the blood. Utilization of AAs in the mammary gland of dairy cows has attracted the great interest of researchers because of the goal of increasing MP yield. Supplying sufficient and balanced AAs is critical to improve MP concentration and yield in dairy cows. Great progress has been made in understanding limiting AAs and their requirements for MP synthesis in dairy cows. This review focuses on the effects of FAA and PBAA supply on MP synthesis and their underlying mechanisms. Advances in our knowledge in the field can help us to develop more accurate models to predict dietary protein requirements for dairy cows MP synthesis, which will ultimately improve the nitrogen utilization efficiency and lactation performance of dairy cows.

16.
J Colloid Interface Sci ; 599: 603-610, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33979743

RESUMO

Water electrolysis is a clean and efficient route for producing high-purity hydrogen. Developing highly efficient, stable and inexpensive electrocatalysts to replace Pt is currently a major challenge for the widespread application of water splitting. Herein, we report a facile and novel strategy for the synthesis of mesoporous NiCo alloy nanoparticle/reduced graphene oxide (MNiCo/rGO) composites via electroless deposition technique. Owing to the synergistic interaction of Ni and Co, the mesoporous structure of NiCo alloy, and the optimized combination of the mesoporous NiCo with rGO, the obtained optimal MNi63Co37/rGO5 catalyst exhibits outstanding electrocatalytic performance for hydrogen evolution reaction (HER) with a low overpotential of 115 mV to reach the current density of 10 mA cm-2, and a small Tafel slope of 45 mV dec-1, as well as a high durability in alkaline solution. These remarkable merits make it a favorable alternative to noble metal Pt-based catalysts for HER, thereby further promoting the development of non-noble metal electrocatalysts.

17.
J Anim Sci ; 99(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33515450

RESUMO

Insulin-like growth factor-I (IGF-I), growth hormone (GH), and prolactin (PRL) play important roles in milk protein synthesis, and their plasma concentrations were reported to be affected by dietary protein intake. To investigate the relationship between circulating amino acid (AA) and concentrations of these hormones, 18 Wistar rats aged 14 wk were assigned to a low (LP; 9% protein), standard (SP; 21% protein), or high-protein (HP; 35% protein) diet from parturition through day 15 of lactation. Plasma, liver, pituitary gland, skeletal muscle, and mammary gland samples were collected at the end of treatment. Circulating and hepatic IGF-I concentrations increased linearly with elevated dietary protein concentrations (P < 0.0001). Rats receiving the HP diet had higher circulating GH (P < 0.01) and pituitary PRL concentrations (P < 0.0001) but lower pituitary GH concentration (P < 0.0001) relative to those in rats receiving the LP and SP diets. Pearson correlation test performed on composed data across treatments showed that several circulating AAs were correlated with circulating and tissue concentrations of IGF-I, GH, and PRL. Multiple linear regression analyses identified Leu, Gln, Ala, Gly, and Arg as the main AAs associated with hormone responses (R2 = 0.37 ~ 0.80; P < 0.05). Rats fed the LP and HP diets had greater Igf1 and Ghr gene expression in skeletal muscle than those fed the SP diets (P < 0.01). However, LP treatment decreased Prlr mRNA abundance in mammary glands as compared with the SP and HP treatments (P < 0.05). The HP diets increased AA transporter expression (P < 0.01) but decreased mammalian target of rapamycin (P < 0.05) and 70 kDa ribosomal protein S6 kinase 1 (P < 0.01) phosphorylation in mammary glands as compared with the LP and SP diets. The results of the present study suggested that several circulating AAs mediated the effects of dietary protein supply on concentrations of IGF-I, GH, and PRL, which in turn altered the metabolism status in peripheral tissues including the lactating mammary glands.


Assuntos
Lactação , Proteínas do Leite , Aminoácidos , Animais , Dieta/veterinária , Feminino , Hormônio do Crescimento , Fator de Crescimento Insulin-Like I , Glândulas Mamárias Animais , Ratos , Ratos Wistar
18.
Nano Lett ; 20(8): 6206-6214, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32697097

RESUMO

Herein, we report efficient single copper atom catalysts that consist of dense atomic Cu sites dispersed on a three-dimensional carbon matrix with highly enhanced mesoporous structures and improved active site accessibility (Cu-SA/NC(meso)). The ratio of +1 to +2 oxidation state of the Cu sites in the Cu-SA/NC(meso) catalysts can be controlled by varying the urea content in the adsorption precursor, and the activity for ORR increases with the addition of Cu1+ sites. The optimal Cu1+-SA/NC(meso)-7 catalyst with highly accessible Cu1+ sites exhibits superior ORR activity in alkaline media with a half-wave potential (E1/2) of 0.898 V vs RHE, significantly exceeding the commercial Pt/C, along with high durability and enhanced methanol tolerance. Control experiments and theoretical calculations demonstrate that the superior ORR catalytic performance of Cu1+-SA/NC(meso)-7 catalyst is attributed to the atomically dispersed Cu1+ sites in catalyzing the reaction and the advantage of the introduced mesoporous structure in enhancing the mass transport.

19.
J Colloid Interface Sci ; 554: 177-182, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31299545

RESUMO

Three-dimensionally ordered macro-/mesoporous carbon (OMMC)-supported Ag nanoparticles (Ag/OMMC) with homogeneously dispersed Ag particles are prepared and investigated as effective electrocatalysts for oxygen reduction reaction (ORR) in alkaline aqueous system. The obtained Ag/OMMC catalyst displays smaller Ag particle size, higher Ag dispersion, and enhanced catalytic activity and durability compared with the carbon black Vulcan XC-72R supported Ag (Ag/XC-72R). The sizes of Ag particles supported on the OMMC and XC-72R are 4.3 and 6.5 nm, respectively. The prepared Ag/OMMC catalyst shows a positive half-wave potential of 0.79 V vs. RHE and a large diffusion-limited current of 5.6 mA cm-2 at 0.4 V, superior to Ag/XC-72R catalyst. The better ORR performance of the Ag/OMMC is probably ascribed to the unique 3D ordered interconnected macro-/mesoporous structure, which contributes to facilitating the mass/charge transport, improving the Ag particle dispersion, and preventing the Ag particle growth and aggregation.

20.
FEBS J ; 286(9): 1645-1655, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30748104

RESUMO

Diabetic cardiomyopathy (DCM)-ventricular dysfunction in the absence of underlying heart disease-is a common complication of diabetes and a leading cause of mortality associated with the disease. In DCM, cardiac fibrosis is the main cause of heart failure. Although it is well-established that the transforming growth factor-beta signaling pathway plays a part in inducing cardiac fibrosis in DCM, details of the molecular mechanism involved remain elusive. Therefore, it is crucial to study the gene reg;ulation of key signaling effectors in DCM-associated cardiac fibrosis. A recently emerged hotspot in the field of gene regulation is the role of long noncoding RNAs (lncRNAs). Recent evidence indicates that lncRNAs play a critical role in cardiac fibrosis; however, in DCM, the function of these regulatory RNAs have not been studied in depth. In this study, we identified a conserved cardiac-specific lncRNA named colorectal neoplasia differentially expressed (Crnde). By analyzing 376 human heart tissues, it was found that Crnde expression is negatively correlated with that of cardiac fibrosis marker genes. Moreover, Crnde expression was shown to be enriched in cardiac fibroblasts (CFs). Overexpression of Crnde attenuated cardiac fibrosis and enhanced cardiac function in mice with DCM. Further, in vitro experiments showed that Crnde negatively regulates the myofibroblast differentiation of CFs. The expression of Crnde was activated by SMAD family member 3 (Smad3), shedding light on the underlying molecular mechanism. Interestingly, Crnde also inhibited the transcriptional activation of Smad3 on target genes, thereby inhibiting the expression of myofibroblastic marker genes in CFs. Overall, our data provide valuable insights into the development of potential anti-cardiac fibrosis strategies centered on lncRNAs, for the treatment of DCM.


Assuntos
Cardiomiopatias Diabéticas/genética , RNA Longo não Codificante/fisiologia , Proteína Smad3/fisiologia , Animais , Dependovirus/genética , Diabetes Mellitus Experimental/complicações , Cardiomiopatias Diabéticas/patologia , Retroalimentação Fisiológica , Fibroblastos/metabolismo , Fibrose , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Especificidade de Órgãos , RNA Antissenso/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Volume Sistólico , Transcrição Gênica
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