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1.
J Genet Genomics ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38575112

RESUMO

Pathological myocardial hypertrophy is a common early clinical manifestation of heart failure, with noncoding RNAs exerting regulatory influence. However, the molecular function of circular RNAs (circRNAs) in the progression from cardiac hypertrophy to heart failure remains unclear. To uncover functional circRNAs and identify the core circRNA signaling pathway in heart failure, we construct a global triple network (microRNA, circRNA, and mRNA) based on the competitive endogenous RNA (ceRNA) theory. We observe that cardiac hypertrophy related circRNA (circRNA CHRC), within the ceRNA network, is down-regulated in both transverse aortic constriction (TAC) mice and Ang-II--treated primary mouse cardiomyocytes. Silencing circRNA CHRC increases cross-sectional cell area, atrial natriuretic peptide, and ß-myosin heavy chain levels in primary mouse cardiomyocytes. Further screening reveals that circRNA CHRC targets the miR-431-5p/KLF15 axis implicated in heart failure progression in vivo and in vitro. Immunoprecipitation with anti-Ago2-RNA confirms the interaction between circRNA CHRC and miR-431-5p, while miR-431-5p mimics reverse Klf15 activation caused by circRNA CHRC overexpression. In summary, circRNA CHRC attenuates cardiac hypertrophy via sponging miR-431-5p to maintain the normal level of Klf15 expression.

2.
ACS Appl Mater Interfaces ; 16(13): 16152-16163, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38502964

RESUMO

The synthesis of anode materials plays an important role in determining the production efficiency, cost, and performance of lithium-ion batteries (LIBs). However, a low-cost, high-speed, scalable manufacturing process of the anode with the desired structural feature for practical technology adoption remains elusive. In this study, we propose a novel method called in situ flash shunt-electrothermal shock (SETS) which is controllable, fast, and energy-saving for synthesizing metal oxide-based materials. By using the example of direct electrothermal decomposition of ZIF-67 precursor loaded onto copper foil support, we achieve rapid (0.1-0.3 s) pyrolysis and generate porous hollow cubic structure material consisting of carbon-coated ultrasmall (10-15 nm) subcrystalline CoO/Co nanoparticles with controllable morphology. It was shown that CoO/Co@N-C exhibits prominent electrochemical performance with a high reversible capacity up to 1503.7 mA h g-1 after 150 cycles at 0.2 A g-1and stable capacities up to 434.1 mA h g-1 after 400 cycles at a high current density of 6 A g-1. This fabrication technique integrates the synthesis of active materials and the formation of electrode sheets into one process, thus simplifying the preparation of electrodes. Due to the simplicity and scalability of this process, it can be envisaged to apply it to the synthesis of metal oxide-based materials and to achieve large-scale production in a nanomanufacturing process.

3.
Front Pharmacol ; 14: 1144878, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033663

RESUMO

Tea has long been valued for its health benefits, especially its potential to prevent and treat atherosclerosis (AS). Abnormal lipid metabolism and oxidative stress are major factors that contribute to the development of AS. Tea, which originated in China, is believed to help prevent AS. Research has shown that tea is rich in catechins, which is considered a potential source of natural antioxidants. Catechins are the most abundant antioxidants in green tea, and are considered to be the main compound responsible for tea's antioxidant activity. The antioxidant properties of catechins are largely dependent on the structure of molecules, and the number and location of hydroxyl groups or their substituents. As an exogenous antioxidant, catechins can effectively eliminate lipid peroxidation products. They can also play an antioxidant role indirectly by activating the endogenous antioxidant system by regulating enzyme activity and signaling pathways. In this review, we summarized the preventive effect of catechin in AS, and emphasized that improving the antioxidant effect and lipid metabolism disorders of catechins is the key to managing AS.

4.
IEEE Trans Cybern ; 53(11): 7275-7284, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36279357

RESUMO

This article develops a new controller design approach to stabilize system states onto the equilibrium at an arbitrarily selected time instant irrespective of the initial system states and parameters. By the stabilization approach, the actual convergence time (not the bound of actual convergence time) is independent of the initial value of system states. This feature differentiates our proposed prescribed-instant stability from conventional fixed, predefined, and prescribed time stability. In this work, we propose the controller design method for the prescribed-instant stability of n -order integrator systems. The proposed control is bounded and can gradually go to zero at an arbitrarily selected time instant, at which the system states reach zero simultaneously. This special stability of the controlled system is analyzed by reduction to absurdity. In simulations, an example of comparison with frequently used prescribed-time control is presented to show the difference. Moreover, the proposed stabilization method is validated by a magnetic suspension system with matched disturbances.

5.
Ying Yong Sheng Tai Xue Bao ; 33(3): 677-684, 2022 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-35524519

RESUMO

A reduction of chemical fertilizers and improving fertilizer utilization rate are important for ensuring a balance between plant growth and minimizing the degradation of the black soil. We conducted a 2-year pot experiment with four treatments during 2019 and 2020, including T0: no fertilizer, T1: conventional use of chemical fertilizer, T2: 15% reduction of the chemical fertilizer combined with 400 kg·hm-2 of humic acid bio-fertilizer (HABF), and T3: 30% reduction of the chemical fertilizer combined with 600 kg·hm-2 of HABF, to examine the effect of reduction rates of chemical fertilizers combined with the HABF on soil microbial abundance, enzyme activity and nutrient content in maize cultivation. The results showed that the application of HABF significantly increased the abundance of soil bacteria and fungi, with the number of microbial colonies being positively correlated with the amount of HABF. When measured at the tassel stage of maize growth, T2 and T3 treatments significantly increased the activities of urease, sucrase, and catalase in soil by 11.4%-21.6%, 34.9%-46.7%, and 6.5%-13.4%, respectively. The available nitrogen contents in T2 and T3 treatments were higher than that in the T1 treatment by 8.2%-18.1%, which ensured the sufficient nitrogen supply to maize after the tassel stage. Soil available phosphorus and available potassium contents increased by 17.1%-121.0% and 9.6%-57.3%, respectively, compared with T1 treatment. With the increases of the amount of HABF, the activation effects of soil phosphorus and potassium and dry matter mass per plant increased significantly in T2 and T3 treatments compared with T1 treatment. In conclusion, HABF promoted the proliferation of soil bacteria and fungi, improved activities of catalase, urease, and sucrase, soil nutrient contents, and dry matter mass per plant. The 15% reduction of chemical fertilizer combined with 400 kg·hm-2 of HABF is the most suitable nutrient management strategy for maize production in black soil.


Assuntos
Fertilizantes , Solo , Agricultura/métodos , Bactérias , Catalase , Fertilizantes/análise , Substâncias Húmicas , Nitrogênio/análise , Fósforo , Potássio , Solo/química , Sacarase , Urease , Zea mays
6.
Membranes (Basel) ; 11(12)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34940452

RESUMO

In this study, a triple-component copolymer of P(Stx-co-MAAy)-g-fPEGz containing hydrophobic (styrene, St), hydrophilic (methacrylic acid, MAA), and oleophobic (perfluoroalkyl polyethylene glycol, fPEG) segments was synthesized and used as an additive polymer to prepare modified PVDF membrane for enhanced anti-fouling performance. Two compositions of St:MAA at 4:1 and 1:1 for the additive and two blending ratios of the additive:PVDF at 1:9 and 3:7 for the modified membranes were specifically examined. The results showed that the presence of the copolymer additive greatly affected the morphology and performance of the modified PVDF membranes. Especially, in a lower ratio of St to MAA (e.g., St:MAA at 1:1 versus 4:1), the additive polymer and therefore the modified PVDF membrane exhibited both better hydrophilic as well as oleophobic surface property. The prepared membrane can achieve a water contact angle at as low as 48.80° and display an underwater oil contact angle at as high as 160°. Adsorption experiments showed that BSA adsorption (in the concentration range of 0.8 to 2 g/L) on the modified PVDF membrane can be reduced by as much as 93%. From the filtration of BSA solution, HA solution, and oil/water emulsion, it was confirmed that the obtained membrane showed excellent resistance to these organic foulants that are often considered challenging in membrane water treatment. The performance displayed slow flux decay during filtration and high flux recovery after simple water cleaning. The developed membrane can therefore have a good potential to be used in such applications as water and wastewater treatment where protein and other organic pollutants (including oils) may cause severe fouling problems to conventional polymeric membranes.

7.
Membranes (Basel) ; 11(6)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34073012

RESUMO

In this study, PVDF/PTFE composite membranes were prepared by adding a PTFE nanoemulsion to a PVDF solution and casting it through the conventional non-solvent-induced phase separation method. The objective was to explore the effectiveness of using a simple and economical method to modify PVDF membranes with PTFE to enhance their anticorrosion performance, especially under highly acidic or alkaline conditions. PTFE nanoparticles (of around 200 nm in size) in nanoemulsion form were blended with PVDF at a mass ratio of PTFE:PVDF in the range of 0-0.3:1. The obtained membranes were examined to determine the effect of the added PTFE nanoparticles on the structure of the modified PVDF membranes as well as on their mechanical strength and surface characteristics. The membranes were then immersed in various concentrations of acidic or alkaline solutions for varied durations ranging from a few days up to as long as 180 days (6 months). The impacts of by the corrosive solutions on the tensile strength, surface roughness, and water flux of the membranes with different exposure times were quantified. The results showed that although a certain extent of change may occur with extended immersion times, greatly enhanced anticorrosion performance was obtained with the prepared PVDF/PTFE membranes compared with the unmodified PVDF membrane. For example, after being immersed in 5 mol-H+··L-1 H2SO4, HCl, and HNO3 solutions for 6 months, the tensile strength at breaking point remained at up to 69.70, 74.07, and 71.38%, respectively, of the initial strength for the PVDF/PTFE (M30) membrane. This was in contrast to values of only 55.77, 70.43, and 61.78% for the unmodified PVDF membrane (M0). Although the water flux and surface roughness showed a change trends to the tensile strength, the PVDF/PTFE (M30) membrane had much higher stability than the PVDF (M0) membrane. In a continuous filtration experiment containing H2SO4 at 0.01 mol-H+·L-1 for 336 h (14 days), the PVDF/PTFE membrane showed a maximum flux change of less than 30%. This was in comparison with a change of up to 50% for the PVDF membrane. However, the PVDF/PTFE membranes did not seem to have a greatly enhanced anticorrosion performance in the alkaline solution environment tested.

8.
Zool Res ; 40(5): 343-348, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31393095

RESUMO

Research on in vitro culture and gene editing of domestic spermatogonial stem cells (SSCs) is of considerable interest but remains a challenging issue in animal science. In recent years, some progress on the isolation, purification, and genetic manipulation of porcine SSCs has been reported. Here, we summarize the characteristics of porcine SSCs as well current advances in their in vitro culture, potential usage, and genetic manipulation. Furthermore, we discuss the current application of gene editing in pig cloning technology. Collectively, this commentary aims to summarize the progress made and obstacles encountered in porcine SSC research to better serve animal husbandry, improve livestock fecundity, and enhance potential clinical use.


Assuntos
Células-Tronco Germinativas Adultas , Edição de Genes , Espermatogônias , Suínos/genética , Animais , Masculino
9.
Stem Cells ; 37(8): 1095-1107, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31041846

RESUMO

Female germline stem cells (FGSCs) are rare population residing in cortex of ovary, with the potential to rescue female infertility caused by ovary failure. Recently, we reported that cadherin-22 (CDH22), a member of cadherin family, regulates self-renewal of mouse FGSCs via interaction with JAK-STAT signal pathway and ß-catenin. In this study, the expression profiles of FGSCs and spermatogonial stem cells (SSCs) were analyzed to further reveal their similarity and difference, and AKT3 was predicted as a pivotal molecule for FGSCs self-renewal. Then, we demonstrated that CDH22 interacted with PI3K to phosphorylate AKT3 and subsequently enhanced the expression levels of N-myc and cyclin family in FGSCs to promote self-renewal. Moreover, glial cell line-derived neurotrophic factor (GDNF) was identified as an essential factor for FGSCs self-renewal with a more complicated mechanism: GDNF-GFRA1 activates AKT3 via PI3K or Src family kinase (SFK), and SFK upregulates its target genes, Bcl6b, Etv5, and Lhx1, to promote self-renewal of FGSCs. However, Src, the key intermediate factor for SSCs, was not the functional molecule of SFK family in the GDNF signal network of FGSCs. Based on the observations of bioinformatics analysis and molecular evidence, we demonstrate the underlying links of potential factors which are critical to the self-renewal in FGSC and imply the therapeutic potentials of FGSCs in cure of female infertility. Stem Cells 2019;37:1095-1107.


Assuntos
Caderinas/metabolismo , Células Germinativas/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Animais , Caderinas/genética , Feminino , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Camundongos , Proteínas Proto-Oncogênicas c-akt/genética
10.
PLoS One ; 5(12): e14270, 2010 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-21151563

RESUMO

BACKGROUND: The 2009 swine-origin influenza virus (S-OIV) H1N1 pandemic has caused more than 18,000 deaths worldwide. Vaccines against the 2009 A/H1N1 influenza virus are useful for preventing infection and controlling the pandemic. The kinetics of the immune response following vaccination with the 2009 A/H1N1 influenza vaccine need further investigation. METHODOLOGY/PRINCIPAL FINDINGS: 58 volunteers were vaccinated with a 2009 A/H1N1 pandemic influenza monovalent split-virus vaccine (15 µg, single-dose). The sera were collected before Day 0 (pre-vaccination) and on Days 3, 5, 10, 14, 21, 30, 45 and 60 post vaccination. Specific antibody responses induced by the vaccination were analyzed using hemagglutination inhibition (HI) assay and enzyme-linked immunosorbent assay (ELISA). After administration of the 2009 A/H1N1 influenza vaccine, specific and protective antibody response with a major subtype of IgG was sufficiently developed as early as Day 10 (seroprotection rate: 93%). This specific antibody response could maintain for at least 60 days without significant reduction. Antibody response induced by the 2009 A/H1N1 influenza vaccine could not render protection against seasonal H1N1 influenza (seroconversion rate: 3% on Day 21). However, volunteers with higher pre-existing seasonal influenza antibody levels (pre-vaccination HI titer ≥1∶40, Group 1) more easily developed a strong antibody protection effect against the 2009 A/H1N1 influenza vaccine as compared with those showing lower pre-existing seasonal influenza antibody levels (pre-vaccination HI titer <1∶40, Group 2). The titer of the specific antibody against the 2009 A/H1N1 influenza was much higher in Group 1 (geometric mean titer: 146 on Day 21) than that in Group 2 (geometric mean titer: 70 on Day 21). CONCLUSIONS/SIGNIFICANCE: Recipients could gain sufficient protection as early as 10 days after vaccine administration. The protection could last at least 60 days. Individuals with a stronger pre-existing seasonal influenza antibody response may have a relatively higher potential for developing a stronger humoral immune response after vaccination with the 2009 A/H1N1 pandemic influenza vaccine.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Animais , Anticorpos Antivirais/química , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Testes de Inibição da Hemaglutinação/métodos , Hemaglutininas/química , Humanos , Sistema Imunitário , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Pandemias/prevenção & controle , Estações do Ano , Fatores de Tempo
11.
Acta Biochim Biophys Sin (Shanghai) ; 42(12): 847-53, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21062789

RESUMO

DNA immunization is an efficient method for high-affinity monoclonal antibody generation. Here, we describe the generation of several high-quality monoclonal antibodies (mAbs) against retinol-binding protein 4 (RBP4), an important marker for kidney abnormality and dysfunction, with a combination method of DNA priming and protein boost. The mAbs generated could bind to RBP4 with high sensitivity and using these mAbs, an immunocolloidal gold fast test strip was constructed. The strip can give a result in <5 min and is very sensitive with a detection limit of about 1 ng/ml. A small-scale clinical test revealed that the result of this strip was well in accordance with that of an enzyme-labeled immunosorbent assay kit currently available on the market. Consequently, it could be useful for more convenient and faster RBP4 determination in the clinic.


Assuntos
Anticorpos Monoclonais/imunologia , DNA/imunologia , Coloide de Ouro , Imunização/métodos , Nefropatias/patologia , Proteínas Plasmáticas de Ligação ao Retinol/imunologia , Sequência de Bases , DNA/genética , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Nefropatias/genética , Kit de Reagentes para Diagnóstico , Fitas Reagentes , Proteínas Plasmáticas de Ligação ao Retinol/genética , Sensibilidade e Especificidade
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 41(1): 158-61, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20369494

RESUMO

OBJECTIVE: To establish a method for the simultaneous determination of 5 water-soluble vitamins including VB1, VB6, Nicotinic acid, Nicotinamide and Folic acid by high performance liquid chromatography. METHODS: Methanol (200 microL) was added to 50 microL human blood sample to precipitate proteins. The sample was frozen (-18 degrees C) for 30 min, and then centrifuged at 8000 r/min for 8 min. The supernatant was subsequently applied to the solid-phase cartridge for further purification. The elute was collected and evaporated to 0.20 mL under nitrogen in a water bath at the temperature of 50 degrees C and finally 50 microL of the sample was injected onto HPLC column for analysis. The five water-soluble vitamins were determined under optimized condition of solid phase extraction and chromatograph. RESULTS: The optimized condition for solid phase extraction (SPE) was identified as: AGT cleanert ODS C18 column as SPE column and CH3OH (2.4 mL)-H2O (0.6 mL) mixed liquor as eluent, with a flow rate of elution of 0.5 mL/min. The optimized chromatographic condition was identified as, Phenomenex C18 Luna column (250 x 4.6 mm, 5 microm) as analytical column under a temperature of 20 degrees C and 0.05 mol/L potassium dehydrogenates phosphate buffer (pH 6.0) and methanol as gradient elution with mobile phase with a flow rate of 0.9 mL/min. The detection wavelength was 266 nm. The correlation coefficients for the standard curves were greater than 0.999 in the range from 0 to 100 ng (RSD < 5%). The detection limits (S/N 2) ranged from 0.076 to 0.170 microg/mL. The recovery rate ranged from 80.2% to 115.0%. Except for Nicotinamide, the other four vitamins were detected successfully in the blood sample. CONCLUSION: This quick and convenient method can be applied to the simultaneous determination of 4 water-soluble vitamins in human serum samples. But the sensitivity for detecting Nicotinamide needs to be improved.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Niacina/sangue , Tiamina/sangue , Vitamina B 6/sangue , Ácido Fólico/sangue , Humanos , Niacinamida/sangue
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