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1.
Nat Immunol ; 18(9): 973-984, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28671690

RESUMEN

The balance of myeloid populations and lymphoid populations must be well controlled. Here we found that osteopontin (OPN) skewed this balance during pathogenic conditions such as infection and autoimmunity. Notably, two isoforms of OPN exerted distinct effects in shifting this balance through cell-type-specific regulation of apoptosis. Intracellular OPN (iOPN) diminished the population size of myeloid progenitor cells and myeloid cells, and secreted OPN (sOPN) increase the population size of lymphoid cells. The total effect of OPN on skewing the leukocyte population balance was observed as host sensitivity to early systemic infection with Candida albicans and T cell-mediated colitis. Our study suggests previously unknown detrimental roles for two OPN isoforms in causing the imbalance of leukocyte populations.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Candidiasis/inmunología , Colitis/inmunología , Infecciones/inmunología , Linfocitos/inmunología , Células Mieloides/inmunología , Osteopontina/inmunología , Animales , Apoptosis , Candida albicans , Proliferación Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Linfopoyesis/inmunología , Ratones , Ratones Noqueados , Mielopoyesis/inmunología , Osteopontina/genética , Isoformas de Proteínas , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T
2.
FASEB J ; 37(8): e23099, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37462453

RESUMEN

The abnormal lipid metabolism in diabetic cardiomyopathy can cause myocardial mitochondrial dysfunction, lipotoxicity, abnormal death of myocardial cells, and myocardial remodeling. Mitochondrial homeostasis and normal lipid metabolism can effectively slow down the development of diabetic cardiomyopathy. Recent studies have shown that SIRT6 may play an important role in the pathological changes of diabetic cardiomyopathy such as myocardial cell death, myocardial hypertrophy, and myocardial fibrosis by regulating mitochondrial oxidative stress and glucose and lipid metabolism. Therefore, understanding the function of SIRT6 and its role in the pathogenesis of diabetic cardiomyopathy is of great significance for exploring and developing new targets and drugs for the treatment of diabetic cardiomyopathy. This article reviews the latest findings of SIRT6 in the pathogenesis of diabetic cardiomyopathy, focusing on the regulation of mitochondria and lipid metabolism by SIRT6 to explore potential clinical treatments.


Asunto(s)
Diabetes Mellitus , Cardiomiopatías Diabéticas , Sirtuinas , Humanos , Cardiomiopatías Diabéticas/metabolismo , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Mitocondrias/metabolismo , Sirtuinas/metabolismo , Diabetes Mellitus/metabolismo
3.
J Org Chem ; 89(11): 7579-7590, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38781579

RESUMEN

A metal-free, mild, and efficient method for the synthesis of amides has been developed from the amination of aldehydes with hydroxylamines promoted by TBAF·3H2O in the presence of KOH. Control experiments showed that the nitrone was the intermediate of this amination. By this method, a series of amides, biologically active compounds bebenil and a COX inhibitor were obtained in moderate to good yields.

4.
Angew Chem Int Ed Engl ; 63(3): e202313791, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38050643

RESUMEN

The blend nanomorphology of electron-donor (D) and -acceptor (A) materials is of vital importance to achieving highly efficient organic solar cells. Exogenous additives especially aromatic additives are always needed to further optimize the nanomorphology of blend films, which is hardly compatible with industrial manufacture. Herein, we proposed a unique approach to meticulously modulate the aggregation behavior of NFAs in both crystal and thin film nanomorphology via self-regulation effect. Nonfullerene acceptor Z9 was designed and synthesized by tethering phenyl groups on the inner side chains of the Y6 backbone. Compared with Y6, the tethered phenyl groups participated in the molecular aggregation via the π-π stacking of phenyl-phenyl and phenyl-2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (IC-2F) groups, which induced 3D charge transport with phenyl-mediated super-exchange electron coupling. Moreover, ordered molecular packing with suitable phase separation was observed in Z9-based blend films. High power conversion efficiencies (PCEs) of 19.0 % (certified PCE of 18.6 %) for Z9-based devices were achieved without additives, indicating the great potential of the self-regulation strategy in NFA design.

5.
Angew Chem Int Ed Engl ; : e202410250, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38887820

RESUMEN

Photocatalysts based on single atoms (SAs) modification can lead to unprecedented reactivity with recent advances. However, the deactivation of SAs-modified photocatalysts remains a critical challenge in the field of photocatalytic CO2 reduction. In this study, we unveil the detrimental effect of CO intermediates on Cu single atoms (Cu-SAs) during photocatalytic CO2 reduction, leading to clustering and deactivation on TiO2. To address this, we developed a novel Cu-SAs anchored on Au porous nanoparticles (CuAu-SAPNPs-TiO2) via a vectored etching approach. This system not only enhances CH4 production with a rate of 748.8 µmol·g-1·h-1 and 93.1% selectivity but also mitigates Cu-SAs clustering, maintaining stability over 7 days. This sustained high performance, despite the exceptionally high efficiency and selectivity in CH4 production, highlights the CuAu-SAPNPs-TiO2 overarching superior photocatalytic properties. Consequently, this work underscores the potential of tailored SAs-based systems for efficient and durable CO2 reduction by reshaping surface adsorption dynamics and optimizing the thermodynamic behavior of the SAs.

6.
Am J Respir Cell Mol Biol ; 68(1): 39-48, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36227725

RESUMEN

Bronchomotor tone modulated by airway smooth muscle shortening represents a key mechanism that increases airway resistance in asthma. Altered glucose metabolism in inflammatory and airway structural cells is associated with asthma. Although these observations suggest a causal link between glucose metabolism and airway hyperresponsiveness, the mechanisms are unclear. We hypothesized that glycolysis modulates excitation-contraction coupling in human airway smooth muscle (HASM) cells. Cultured HASM cells from human lung donors were subject to metabolic screenings using Seahorse XF cell assay. HASM cell monolayers were treated with vehicle or PFK15 (1-(Pyridin-4-yl)-3-(quinolin-2-yl)prop-2-en-1-one), an inhibitor of PFKFB3 (PFK-1,6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3) that generates an allosteric activator for glycolysis rate-limiting enzyme PFK1 (phosphofructokinase 1), for 5-240 minutes, and baseline and agonist-induced phosphorylation of MLC (myosin light chain), MYPT1 (myosin phosphatase regulatory subunit 1), Akt, RhoA, and cytosolic Ca2+ were determined. PFK15 effects on metabolic activity and contractile agonist-induced bronchoconstriction were determined in human precision-cut lung slices. Inhibition of glycolysis attenuated carbachol-induced excitation-contraction coupling in HASM cells. ATP production and bronchodilator-induced cAMP concentrations were also attenuated by glycolysis inhibition in HASM cells. In human small airways, glycolysis inhibition decreased mitochondrial respiration and ATP production and attenuated carbachol-induced bronchoconstriction. The findings suggest that energy depletion resulting from glycolysis inhibition is a novel strategy for ameliorating HASM cell shortening and bronchoprotection of human small airways.


Asunto(s)
Asma , Humanos , Carbacol/farmacología , Asma/metabolismo , Pulmón/metabolismo , Miocitos del Músculo Liso/metabolismo , Contracción Muscular , Relajación Muscular , Glucólisis , Glucosa/metabolismo , Adenosina Trifosfato/metabolismo , Células Cultivadas
7.
Am J Physiol Lung Cell Mol Physiol ; 323(3): L297-L307, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35787188

RESUMEN

Obesity can aggravate asthma by enhancing airway hyperresponsiveness (AHR) and attenuating response to treatment. However, the precise mechanisms linking obesity and asthma remain unknown. Human airway smooth muscle (HASM) cells exhibit amplified excitation-contraction (EC) coupling and force generation in obesity. Therefore, we posit that airway smooth muscle (ASM) cells obtained from obese donors manifest a metabolomic phenotype distinct from that of nonobese donor cells and that a differential metabolic phenotype, at least in part, drives enhanced ASM cell EC coupling. HASM cells derived from age-, sex-, and race-matched nonobese [body mass index (BMI) ≤ 24.9 kg·m-2] and obese (BMI ≥ 29.9 kg·m-2) lung donors were subjected to unbiased metabolomic screening. The unbiased metabolomic screening identified differentially altered metabolites linked to glycolysis and citric acid cycle in obese donor-derived cells compared with nonobese donor cells. The Seahorse assay measured the bioenergetic profile based on glycolysis, mitochondrial respiration, palmitate oxidation, and glutamine oxidation rates in HASM cells. Glycolytic rate and capacity were elevated in obese donor-derived HASM cells, whereas mitochondrial respiration, palmitate oxidation, and glutamine oxidation rates were comparable between obese and nonobese groups. PFKFB3 mRNA and protein expression levels were also elevated in obese donor-derived HASM cells. Furthermore, pharmacological inhibition of PFKFB3 attenuated agonist-induced myosin light chain (MLC) phosphorylation in HASM cells derived from obese and nonobese donors. Our findings identify elevated glycolysis as a signature metabolic phenotype of obesity and inhibition of glycolysis attenuates MLC phosphorylation in HASM cells. These findings identify novel therapeutic targets to mitigate AHR in obesity-associated asthma.


Asunto(s)
Asma , Glutamina , Asma/metabolismo , Células Cultivadas , Glutamina/metabolismo , Humanos , Miocitos del Músculo Liso/metabolismo , Cadenas Ligeras de Miosina/metabolismo , Obesidad/metabolismo , Palmitatos/metabolismo
8.
Entropy (Basel) ; 24(3)2022 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-35327894

RESUMEN

A saturation attack can be employed for compromising the practical security of continuous-variable quantum key distribution (CVQKD). In this paper, we suggest a countermeasure approach to resisting this attack by embedding an adjustable optical filter (AOF) in the CVQKD system. Numerical simulations illustrate the effects of the AOF-enabled countermeasure on the performance in terms of the secret key rate and transmission distance. The legal participants can trace back the information that has been eavesdropped by an attacker from the imperfect receiver, which indicates that this approach can be used for defeating a saturation attack in practical quantum communications.

9.
Angew Chem Int Ed Engl ; 61(19): e202116111, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-34962046

RESUMEN

Semitransparent organic solar cells (ST-OSCs) are considered as one of the most valuable applications of OSCs and a strong contender in the market. However, the optical band gap of current high-performance ST-OSCs is still not low enough to achieve the optimal balance between power conversion efficiency (PCE) and average visible transmittance (AVT). An N-substituted asymmetric nonfullerene acceptor SN with over 40 nm bathochromically shifted absorption compared to Y6 was designed and synthesized, based on which the device with PM6 as donor obtained a PCE of 14.3 %, accompanied with a nonradiative voltage loss as low as 0.15 eV. Meanwhile, ternary devices with the addition of SN into PM6 : Y6 can achieve a PCE of 17.5 % with an unchanged open-circuit voltage and improved short-circuit current. Benefiting from extended NIR absorption and lowered voltage loss, ST-OSCs based on PM6 : SN : Y6 were fabricated and the optimized device demonstrated a PCE of 14.0 % at an AVT of 20.2 %, which is the highest PCE at an AVT over 20 %.

10.
Inorg Chem ; 60(11): 8189-8199, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34034489

RESUMEN

An integration hydrogen adsorption benign component such as a metal with an oxygen-containing reactant adsorption benign component such as metal oxide allows for efficient overall water splitting in alkaline solutions and yet remains a considerable challenge. Herein, 5d transition metal oxide WO2 and WO3 (denoted as WOx) nanoparticles are purposely integrated with a porous Ni nanosheet array grown on nickel foam (NF) to design a strongly coupled Ni/WOx/NF porous nanosheet array electrocatalyst. Through the anion exchange of Ni(OH)2 nanosheets with tungstate, followed by hydrogenation treatment, abundant Ni/WOx interfaces with strong coupling interaction are generated. Benefiting from the strong synergies between Ni and WOx and the unique nanostructure, Ni/WOx/NF only requires the overpotentials of 42 mV for hydrogen evolution reaction (HER) and 395.7 mV for oxygen evolution reaction (OER) to achieve the current densities of 10 and 100 mA cm-2, respectively. Furthermore, the Ni/WOx/NF can achieve a current density of 10 mA cm-2 at a low cell voltage of 1.54 V in a two-electrode system. This work opens a novel avenue for the design of high-performance but low-cost electrocatalysts for overall water splitting.

11.
Entropy (Basel) ; 23(12)2021 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-34946004

RESUMEN

We perform security analysis of a passive continuous-variable quantum key distribution (CV-QKD) protocol by considering the finite-size effect. In the passive CV-QKD scheme, Alice utilizes thermal sources to passively make preparation of quantum state without Gaussian modulations. With this technique, the quantum states can be prepared precisely to match the high transmission rate. Here, both asymptotic regime and finite-size regime are considered to make a comparison. In the finite-size scenario, we illustrate the passive CV-QKD protocol against collective attacks. Simulation results show that the performance of passive CV-QKD protocol in the finite-size case is more pessimistic than that achieved in the asymptotic case, which indicates that the finite-size effect has a great influence on the performance of the single-mode passive CV-QKD protocol. However, we can still obtain a reasonable performance in the finite-size regime by enhancing the average photon number of the thermal state.

12.
Respir Res ; 21(1): 256, 2020 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-33032603

RESUMEN

Glucocorticoids (GCs) and ß2-adrenergic receptor (ß2AR) agonists improve asthma outcomes in most patients. GCs also modulate gene expression in human airway smooth muscle (HASM), thereby attenuating airway inflammation and airway hyperresponsiveness that define asthma. Our previous studies showed that the pro-fibrotic cytokine, transforming growth factor- ß1 (TGF-ß1) increases phosphodiesterase 4D (PDE4D) expression that attenuates agonist-induced levels of intracellular cAMP. Decreased cAMP levels then diminishes ß2 agonist-induced airway relaxation. In the current study, we investigated whether glucocorticoids reverse TGF-ß1-effects on ß2-agonist-induced bronchodilation and modulate pde4d gene expression in HASM. Dexamethasone (DEX) reversed TGF-ß1 effects on cAMP levels induced by isoproterenol (ISO). TGF-ß1 also attenuated G protein-dependent responses to cholera toxin (CTX), a Gαs stimulator downstream from the ß2AR receptor. Previously, we demonstrated that TGF-ß1 treatment increased ß2AR phosphorylation to induce hyporesponsiveness to a ß2 agonist. Our current data shows that expression of grk2/3, kinases associated with attenuation of ß2AR function, are not altered with TGF-ß1 stimulation. Interestingly, DEX also attenuated TGF-ß1-induced pde4d gene expression. These data suggest that steroids may be an effective therapy for treatment of asthma patients whose disease is primarily driven by elevated TGF-ß1 levels.


Asunto(s)
Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/biosíntesis , Dexametasona/farmacología , Miocitos del Músculo Liso/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Mucosa Respiratoria/metabolismo , Factor de Crecimiento Transformador beta1/toxicidad , Antiinflamatorios/farmacología , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/genética , Relación Dosis-Respuesta a Droga , Regulación Enzimológica de la Expresión Génica , Humanos , Miocitos del Músculo Liso/efectos de los fármacos , Inhibidores de Fosfodiesterasa 4/farmacología , Mucosa Respiratoria/efectos de los fármacos , Tráquea/química , Tráquea/efectos de los fármacos , Tráquea/metabolismo
13.
Respir Res ; 21(1): 317, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33256729

RESUMEN

BACKGROUND: Activation of free fatty acid receptors (FFAR1 and FFAR4) which are G protein-coupled receptors (GPCRs) with established (patho)physiological roles in a variety of obesity-related disorders, induce human airway smooth muscle (HASM) cell proliferation and shortening. We reported amplified agonist-induced cell shortening in HASM cells obtained from obese lung donors. We hypothesized that FFAR1 modulate excitation-contraction (EC) coupling in HASM cells and play a role in obesity-associated airway hyperresponsiveness. METHODS: In HASM cells pre-treated (30 min) with FFAR1 agonists TAK875 and GW9508, we measured histamine-induced Ca2+ mobilization, myosin light chain (MLC) phosphorylation, and cortical tension development with magnetic twisting cytometry (MTC). Phosphorylation of MLC phosphatase and Akt also were determined in the presence of the FFAR1 agonists or vehicle. In addition, the effects of TAK875 on MLC phosphorylation were measured in HASM cells desensitized to ß2AR agonists by overnight salmeterol treatment. The inhibitory effect of TAK875 on MLC phosphorylation was compared between HASM cells from age and sex-matched non-obese and obese human lung donors. The mean measurements were compared using One-Way ANOVA with Dunnett's test for multiple group comparisons or Student's t-test two-group comparison. For cortical tension measurements by magnetic twisted cytometry, mixed effect model using SAS V.9.2 was applied. Means were considered significant when p ≤ 0.05. RESULTS: Unexpectedly, we found that TAK875, a synthetic FFAR1 agonist, attenuated histamine-induced MLC phosphorylation and cortical tension development in HASM cells. These physiological outcomes were unassociated with changes in histamine-evoked Ca2+ flux, protein kinase B (AKT) activation, or MLC phosphatase inhibition. Of note, TAK875-mediated inhibition of MLC phosphorylation was maintained in ß2AR-desensitized HASM cells and across obese and non-obese donor-derived HASM cells. CONCLUSIONS: Taken together, our findings identified the FFAR1 agonist TAK875 as a novel bronchoprotective agent that warrants further investigation to treat difficult-to-control asthma and/or airway hyperreactivity in obesity.


Asunto(s)
Benzofuranos/farmacología , Broncoconstricción/efectos de los fármacos , Broncodilatadores/farmacología , Histamina/farmacología , Pulmón/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Cadenas Ligeras de Miosina/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Sulfonas/farmacología , Agonistas de Receptores Adrenérgicos beta 2/farmacología , Células Cultivadas , Humanos , Pulmón/metabolismo , Pulmón/fisiopatología , Metilaminas/farmacología , Músculo Liso/metabolismo , Músculo Liso/fisiopatología , Miocitos del Músculo Liso/metabolismo , Obesidad/metabolismo , Obesidad/fisiopatología , Fosforilación , Propionatos/farmacología , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal
14.
Med Sci Monit ; 26: e924393, 2020 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-32920588

RESUMEN

BACKGROUND Myasthenia gravis (MG) is an autoimmune neurological disorder of neuromuscular junctions. In this study we established experimental autoimmune myasthenia gravis (EAMG) rat models to investigate the effects of AEB-071 (AEB), which is a specific inhibitor of protein kinase C that prevents T lymphocyte activation. MATERIAL AND METHODS We utilized animals divided into 4 groups: (1) control rats, (2) EAMG, (3) AEB-071+EAMG, and (4) AZP+EAMG. Drug treatment was continued for 10 days. Ten weeks after immunization we measured body weights, assessed mortality rates, and used Lennon scores to evaluate EAMG grades. We also assessed the proportions of Treg, Th1, Th2, Th17, and lymphocytes using flow cytometry. RESULTS In the absence of drug treatment, we found a significant decline in body weights in the EAMG group in comparison to control rats, and EAMG group rats also had higher Lennon scores (P<0.05). Interestingly, we found that AEB-071 restored the body weight of EAMG rats and the decreased mortality rate compared to AZP treatment. Although a decrease in the number of Treg cells was observed, the proportion of Th lymphocytes was significantly increased in the EAMG group, and AEB-071 treatment decreased the proportion of Th lymphocytes. CONCLUSIONS We concluded that AEB-071 treatment imparts beneficial effects in EAMG rat models by reducing mortality rate and restoring Th lymphocyte balance, and thus may be an attractive candidate for use in MG treatment.


Asunto(s)
Miastenia Gravis Autoinmune Experimental/inmunología , Pirroles/farmacología , Quinazolinas/farmacología , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Femenino , Activación de Linfocitos/efectos de los fármacos , Debilidad Muscular/etiología , Ratas , Ratas Endogámicas Lew
15.
World J Surg Oncol ; 18(1): 245, 2020 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-32919475

RESUMEN

BACKGROUND: Tubal choriocarcinoma is an extremely rare but highly malignant trophoblastic tumor, which may be either gestational or non-gestational in origin. Due to atypical clinical manifestations and symptoms similar to ectopic pregnancy, it is easily to be confused with ectopic pregnancy. In addition, inadequate understanding of this rare disease by clinicians often leads to misdiagnosis or missed diagnosis, which in turn results in delayed treatment or even tumor metastasis. CASE PRESENTATION: This report summarized a case of a woman who was finally diagnosed as tubal choriocarcinoma through the follow-up of serum ß hCG levels and histopathological results after undergoing salpingectomy for being misdiagnosed as ectopic pregnancy. Five courses of adjuvant chemotherapy (5-fluorouracil, actinomycin-D, vinorelbine regime) have been administered to the patient in the prevention of any recurrences. During 1-year follow-up, the patient was asymptomatic and presented no evidence of recurrence. CONCLUSIONS: Tubal choriocarcinoma is easily to be confused with ectopic pregnancy. By analyzing this case and previous related cases, we aimed to provide references for clinicians in the diagnosis and treatment of tubal choriocarcinoma.


Asunto(s)
Coriocarcinoma , Embarazo Ectópico , Embarazo Tubario , Coriocarcinoma/cirugía , Femenino , Humanos , Recurrencia Local de Neoplasia , Embarazo , Embarazo Tubario/diagnóstico por imagen , Embarazo Tubario/cirugía , Pronóstico
16.
Small ; 15(1): e1804271, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30506976

RESUMEN

Nonfullerene polymer solar cells develop quickly. However, nonfullerene small-molecule solar cells (NF-SMSCs) still show relatively inferior performance, attributing to the lack of comprehensive understanding of the structure-performance relationship. To address this issue, two isomeric small-molecule acceptors, NBDTP-Fout and NBDTP-Fin , with varied oxygen position in the benzodi(thienopyran) (BDTP) core are designed and synthesized. When blended with molecular donor BDT3TR-SF, devices based on the two isomeric acceptors show disparate photovoltaic performance. Fabricated with an eco-friendly processing solvent (tetrahydrofuran), the BDT3TR-SF:NBDTP-Fout blend delivers a high power conversion efficiency of 11.2%, ranked to the top values reported to date, while the BDT3TR-SF:NBDTP-Fin blend almost shows no photovoltaic response (0.02%). With detailed investigations on inherent optoelectronic processes as well as morphological evolution, this performance disparity is correlated to the interfacial tension of the two combinations and concludes that proper interfacial tension is a key factor for effective phase separation, optimal blend morphology, and superior performance, which can be achieved by the "isomerization" design on molecular acceptors. This work reveals the importance of modulating the materials miscibility by interfacial-tension-oriented molecular design, which provides a general guideline toward efficient NF-SMSCs.

17.
Biochem Biophys Res Commun ; 490(3): 700-706, 2017 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-28634073

RESUMEN

OBJECTIVE: This study aimed to explore the mechanism of lncRNA MEG3 on angiogenesis after cerebral infarction (CI). METHODS: The rat brain microvascular endothelial cells (RBMVECs) isolated from rat was used to establish CI model, which were treated with oxygen-glucose deprivation/reoxygenation (OGD/R). The genes mRNA and protein expression levels in RBMVECs were determined by the quantitative real-time polymerase chain reaction (RT-qPCR) and western blot, respectively. The flow cytometry was used to measured cell apoptosis and intracellular reactive oxygen species (ROS) generation. The RBMVECs activities was detected by MTT method. The RNA-immunoprecipitation (RIP) assay was used to detect the interaction between MEG3 and p53, and the relationship between p53 and NOX4 was proved by chromatin co-immunoprecipitation (chip) assay. RESULTS: The results showed that OGD or OGD/R increased MEG3 and NOX4 expression, and there was positive correlation between MEG3 and NOX4 expression in RBMVECs. Next, knockdown of MEG3 indicated that inhibition of MEG3 was conducive to protect RBMVECs against OGD/R-induced apoptosis, with decreased NOX4 and p53 expression, further enhanced pro-angiogenic factors (HIF-1α and VEGF) expression, and reduced intracellular ROS generation. And then the RIP and CHIP assay demonstrated that MEG3 could interacted with p53 and regulated its expression, and p53 exerted significant binding in the promoters for NOX4, suggesting that MEG3 regulated NOX4 expression via p53. At last, knockdown of NOX4 indicated that inhibition of NOX4 protected RBMVECs against OGD/R-induced apoptosis, with increased cell viability and pro-angiogenic factors expression, and reduced ROS generation. CONCLUSION: LncRNA MEG3 was an important regulator in OGD/R induced-RBMVECs apoptosis and the mechanism of MEG3 on angiogenesis after CI was reduced ROS by p53/NOX4 axis.


Asunto(s)
Infarto Cerebral/genética , Células Endoteliales/metabolismo , Regulación de la Expresión Génica , NADPH Oxidasas/genética , Neovascularización Fisiológica , ARN Largo no Codificante/genética , Proteína p53 Supresora de Tumor/genética , Animales , Apoptosis , Encéfalo/irrigación sanguínea , Encéfalo/citología , Encéfalo/metabolismo , Células Cultivadas , Infarto Cerebral/metabolismo , Células Endoteliales/citología , Glucosa/metabolismo , NADPH Oxidasa 4 , NADPH Oxidasas/metabolismo , Oxígeno/metabolismo , ARN Largo no Codificante/metabolismo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
18.
Cell Biol Int ; 40(8): 934-42, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27306406

RESUMEN

The remodeling of cardiac gap junctions contributes to various arrhythmias in a diabetic heart. We previously reported that Epigallocatechin-3-gallate (EGCG) attenuated connexin43 (Cx43) protein downregulation induced by high glucose (HG) in neonatal rat cardiomyocytes, but Cx43 mRNA expression was not affected. It indicated the possible mechanisms of post-transcriptional regulation, which still remains unclear. As microRNAs (miRNAs) regulate gene expression widely at post-transcriptional level, we measured miR-1/206 in cardiomyocytes treated with HG and EGCG by quantitative RT-PCR and investigated their relationship with signal transduction pathways. The results showed that HG induced miR-1/206 elevation by PKC MAPK pathway. Moreover, we tested the negative regulation effect of miR-1/206 on Cx43 protein by miRNAs transfection. EGCG, however, nearly abolished the HG-induced miR-1 augmentation via P38 MAPK pathway. Therefore, our study suggested that PKC-activated miR-1/206 expression might contribute to Cx43 downregulation in HG-treated cardiomyocytes, and EGCG conferred protective effect by inhibiting miR-1 elevation via P38 MAPK pathway.


Asunto(s)
Catequina/análogos & derivados , Conexina 43/metabolismo , Glucosa/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , MicroARNs/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Catequina/farmacología , Células Cultivadas , Regulación hacia Abajo , Uniones Comunicantes/efectos de los fármacos , Uniones Comunicantes/fisiología , Glucosa/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Fosforilación , Ratas
19.
Phys Chem Chem Phys ; 18(1): 70-4, 2016 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-26603564

RESUMEN

In this study, ultra-thin and porous molybdenum selenide (MoSe2) nanosheets were prepared through a modified liquid exfoliation method as efficient electrocatalysts for the hydrogen evolution reaction (HER). This novel structure enables the exposure of more catalytically active sites and moreover maintains effective electron transport, resulting in a small peak potential of ∼75 mV as well as long-term durability. In addition, due to the facile and economical preparation method as well as its eco-friendly synthetic conditions, this study provides a high-performance HER catalyst with promising commercial application prospects.

20.
Chemistry ; 21(47): 17016-22, 2015 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-26420200

RESUMEN

Three diaceno[a,e]pentalene analogues with pendant sterically bulky di-tert-butylphenyl groups have been designed and synthesized. With the extension of the conjugated molecular framework, the molecular arrangement is apparently tuned by the balance between the π-extended surface and pendant alkyl or aryl substituents. Theoretical calculations of the morphologies were in good agreement with the experimental results. Ambient-stable field-effect transistors based on dianthraceno[a,e]pentalene (DAP) have been fabricated, which exhibited excellent hole mobilities (up to 6.55 cm(2) V(-1) s(-1)). Thus, this study has shown that diaceno[a,e]pentalenes are stable even with an extraordinarily large π-surface area, and may thus serve as excellent molecular platforms for further exploring high-performance semiconducting materials.

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