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1.
Heart Vessels ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580850

RESUMO

Cardiac amyloidosis is a refractory cardiomyopathy with a poor prognosis and lacks effective treatments. N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin T are poor prognostic factors for myocardial amyloidosis. However, NT-proBNP and troponin also serve as markers of heart failure and myocardial infarction, lacking specificity. Whether abnormal elevation of alpha-1 antitrypsin in myocardial amyloidosis also predicts the poor prognosis of patients remains unknown. We conducted a retrospective single-center case-control study to analyze the serological and physical examination data of 83 cardiac amyloidosis patients and 68 healthy controls matched by gender and age. We aimed to explore the onset and prognostic factors of cardiac amyloidosis. The serum alpha-1 antitrypsin level (169.78 ± 39.59 mg/dl) in patients with cardiac amyloidosis was significantly higher than that in the normal control (125.92 ± 18.26 mg/dl). Logistic regression results showed that alpha-1 antitrypsin, free sialic acid, high-density lipoprotein cholesterol, apolipoprotein A/B ratio, and homocysteine were predictors of cardiac amyloidosis. Multivariable logistic regression showed that only alpha 1 antitrypsin was an independent risk factor for cardiac amyloidosis. Receiver operating characteristic curve analysis based on the Mayo stage and troponin level showed the cut-off value of 140.55 mg/dl for alpha-1 antitrypsin in predicting cardiac amyloidosis with 81.7% sensitivity and 83.9% specificity. Elevated alpha-1 antitrypsin levels may be an early diagnostic biomarker for cardiac amyloidosis.

2.
Small ; 19(46): e2302962, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37518765

RESUMO

Retinal degeneration (RD) is an irreversible blinding disease that seriously affects patients' daily activities and mental health. Targeting hyperactivated microglia and regulating polarization are promising strategies for treating the disease. Mesenchymal stem cell (MSC) transplantation is proven to be an effective treatment due to its immunomodulatory and regenerative properties. However, the low efficiency of cell migration and integration of MSCs remains a major obstacle to clinical use. The goal of this study is to develop a nanodelivery system that targets hyperactivated microglia and inhibits their release of proinflammatory factors, to achieve durable neuroprotection. This approach is to engineer extracellular vesicles (EVs) isolated from MSC, modify them with a cyclic RGD (cRGD) peptide on their surface, and load them with an antagonist of the IL-1 receptor, anakinra. Comparing with non-engineered EVs, it is observed that engineered cRGD-EVs exhibit an increased targeting efficiency against hyperactivated microglia and strongly protected photoreceptors in experimental RD cells and animal models. This study provides a strategy to improve drug delivery to degenerated retinas and offers a promising approach to improve the treatment of RD through targeted modulation of the immune microenvironment via engineered cRGD-EVs.


Assuntos
Vesículas Extracelulares , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Degeneração Retiniana , Animais , Humanos , Degeneração Retiniana/terapia , Degeneração Retiniana/metabolismo , Vesículas Extracelulares/metabolismo , Retina
3.
BMC Cancer ; 23(1): 1204, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062421

RESUMO

BACKGROUND: Though our previous study has demonstrated that the single-incision plus one-port laparoscopic surgery (SILS + 1) is safe and feasible for sigmoid colon and upper rectal cancer and has better short-term outcomes compared with conventional laparoscopic surgery (CLS), the long-term outcomes of SILS + 1 remains uncertain and are needed to evaluated by an RCT. METHODS: Patients with clinical stage T1-4aN0-2M0 rectosigmoid cancer were enrolled. The participants were randomly assigned to either SILS + 1 (n = 99) or CLS (n = 99). The 3-year DFS, 5-year OS, and recurrence patterns were analyzed. RESULTS: Between April 2014 and July 2016, 198 patients were randomly assigned to either the SILS + 1 group (n = 99) or CLS group (n = 99). The median follow-up in the SILS + 1 group was 64.0 months and in CLS group was 65.0 months. The 3-year DFS was 87.8% (95% CI, 81.6-94.8%) in SILS + 1 group and 86.9% (95% CI, 81.3-94.5%) in CLS group (hazard ratio: 1.09 (95% CI, 0.48-2.47; P = 0.84)). The 5-year OS was 86.7% (95% CI,79.6-93.8%) in the SILS + 1 group and 80.5% (95% CI,72.5-88.5%) in the CLS group (hazard ratio: 1.53 (95% CI, 0.74-3.18; P = 0.25)). There were no significant differences in the recurrence patterns between the two groups. CONCLUSIONS: We found no significant difference in 3-year DFS and 5-year OS of patients with sigmoid colon and upper rectal cancer treated with SILS + 1 vs. CLS. SILS + 1 is noninferior to CLS when performed by expert surgeons. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02117557 (registered on 21/04/2014).


Assuntos
Laparoscopia , Neoplasias Retais , Neoplasias do Colo Sigmoide , Ferida Cirúrgica , Humanos , Resultado do Tratamento , Tempo de Internação , Neoplasias Retais/cirurgia , Neoplasias do Colo Sigmoide/cirurgia
4.
Int Heart J ; 64(6): 979-985, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37967991

RESUMO

Recently, the supra-normal left ventricular ejection fraction (snLVEF) has been proposed, based on extensive datasets indicating increased all-cause mortality in individuals with an LVEF exceeding 65%. However, the implications of an LVEF > 65% in the context of acute coronary syndrome (ACS) remain underexplored.The aim of the present study was to investigate the correlation between supra-normal left ventricular ejection fraction (snLVEF) and major adverse cardiovascular events (MACE) in patients with ACS.Methods: A total of 874 ACS patients (560 men, mean age 59.5 ± 10.0; 314 women, mean age 61.5 ± 8.9) who underwent their first coronary angiography during the period from March 2013 to October 2015 were divided into 2 groups: normal LVEF (nLVEF) (55% ≤ EF ≤ 65%) and snLVEF (EF > 65%), according to their echocardiography results. The patients were evaluated for MACE after surgery by collecting clinical data and long-term follow-up data. This correlation was further analyzed by Kaplan-Meier analysis and Cox regression analysis.The follow-up data revealed a significantly higher incidence of MACE among snLVEF patients compared to the nLVEF group (15.6% versus 7.4%; P = 0.020). This heightened risk persisted even after adjustment for multiple variables, indicating a strong association between snLVEF and increased MACE risk (HR: 2.346; 95% CI: 1.196-4.602; P = 0.013).SnLVEF was independently associated with poor prognosis after ACS. Enhanced management strategies for snLVEF patients could potentially reduce the incidence of MACE in ACS patients.


Assuntos
Síndrome Coronariana Aguda , Função Ventricular Esquerda , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Volume Sistólico , Prognóstico , Análise de Regressão
5.
Small ; 18(41): e2202161, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36089650

RESUMO

It is highly desirable to design a single modality that can simultaneously trigger apoptosis and ferroptosis to efficiently eliminate tumor progression. Herein, a nanosystem based on the intrinsic properties of tumor microenvironment (TME) is designed to achieve tumor control through the simultaneous induction of ferroptosis and apoptosis. CuCP molecules are encapsulated in a liposome-based nanosystem to assemble into biocompatible and stable CuCP nanoparticles (CuCP Lipo NPs). This nanosystem intrinsically possesses nanozymatic activity and photothermal characteristics due to the property of Cu atoms and the structure of CuCP Lipo NPs. It is demonstrated that the synergistic strategy increases the intracellular lipid-reactive oxides species, induces the occurrence of ferroptosis and apoptosis, and completely eradicates the tumors in vivo. Proteomics analysis further discloses the key involved proteins (including Tp53, HMOX1, Ptgs2, Tfrc, Slc11a2, Mgst2, Sod1, and several GST family members) and pathways (including apoptosis, ferroptosis, and ROS synthesis). Conclusively, this work develops a strategy based on one nanosystem to synergistically induce ferroptosis and apoptosis in vivo for tumor suppression, which holds great potential in the clinical translation for tumor therapy.


Assuntos
Ferroptose , Nanopartículas , Neoplasias , Apoptose , Linhagem Celular Tumoral , Ciclo-Oxigenase 2 , Lipídeos , Lipossomos , Nanopartículas/química , Neoplasias/terapia , Óxidos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase-1 , Microambiente Tumoral
6.
J Cell Mol Med ; 25(23): 11031-11034, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34766437

RESUMO

The administration of ACEI/ARB (angiotensin-converting enzyme inhibitors/Angiotension II receptor blockers) in COVID-19 (coronavirus disease 2019) patients with hypertension exhibits a lower risk of mortality compared with ACEI/ARB non-users. In this context, an important question arises: is ACEI or ARB more suitable for the treatment of hypertensive COVID-19 patients? Taken into consideration the following four rationales, ARB may offer a more significant benefit than ACEI for the short-term treatment of hypertensive COVID-19 patients: 1. ACEI has no inhibition on non-ACE-mediated Ang II production under infection conditions, whereas ARB can function properly regardless of how Ang II is produced; 2. ACEI-induced bradykinin accumulation may instigate severe ARDS while ARB has no effects on kinin metabolism; 3. ARB alleviates viscous sputa production and inflammatory reaction significantly in contrast to ACEI; 4. ARB may attenuate the lung fibrosis induced by mechanical ventilation in severe patients and improve their prognosis significantly compared with ACEI. To examine the advantages of ARB over ACEI on hypertensive COVID-19 patients, retrospective case-control studies comparing the clinical outcomes for COVID-19 patients receiving ARB or ACEI treatment is strikingly needed in order to provide guidance for the clinical application.


Assuntos
Bloqueadores do Receptor Tipo 2 de Angiotensina II/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Tratamento Farmacológico da COVID-19 , Hipertensão/tratamento farmacológico , Humanos
7.
IUBMB Life ; 72(12): 2546-2562, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053610

RESUMO

Exosomes are nano-sized extracellular vesicles containing a cell-specific biologically active cargo of proteins and genetic materials. Exosomes are constitutively released from almost all cell-types and affect neighboring or distant cells through a complex intercellular exchange of the genetic information and/or regulation of certain gene expressions that change the function and behavior of recipient cells. Those released into body fluids are the major mediators of intercellular communications. The success of the biological functions of exosomes is highly mediated by the effective transfer of microRNAs (miRs). Exosomes secreted by a damaged or diseased heart can exhibit alterations in the miRs' profile that may reflect the cellular origin and (patho)physiological state, as a "signature" or "fingerprint" of the donor cell. It has been shown that the transportation of cardiac-specific miRs in exosomes can be rapidly detected and measured, holding great potential as biomarkers in heart diseases. Currently, the search for new biomarkers of heart diseases remains a large and increasing enterprise. Notably, circulating exosomal miRs (Exo-miRs) have successfully gained huge interests for their diagnostic and prognostic potentials. The present review highlights circulating Exo-miRs explored for diagnosis/prognosis and outcome prediction in patients with heart failure (HF). To this end, we explain the feasibility of exosomes as clinical biomarkers, discuss the priority of circulating Exo-miRs over non-exosomal ones as a biomarker, and then outline reported circulating Exo-miRs having the biomarker function in HF patients, together with their mechanism of action. In conclusion, circulating Exo-miRs represent emerging diagnostic (Exo-miR-92b-5p, Exo-miR-146a, Exo-miR-181c, and Exo-miR-495) and prognostic (Exo-miR-192, Exo-miR-194, Exo-miR-34a, Exo-miR-425, Exo-miR-744) biomarkers for HF.


Assuntos
Biomarcadores/sangue , Exossomos/genética , Insuficiência Cardíaca/diagnóstico , MicroRNAs/genética , Nanopartículas/química , Animais , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/genética , Humanos , MicroRNAs/sangue
8.
Crit Care ; 24(1): 219, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32410714

RESUMO

BACKGROUND: A COVID-19 outbreak started in Wuhan, China, last December and now has become a global pandemic. The clinical information in caring of critically ill patients with COVID-19 needs to be shared timely, especially under the situations that there is still a largely ongoing spread of COVID-19 in many countries. METHODS: A multicenter prospective observational study investigated all the COVID-19 patients received in 19 ICUs of 16 hospitals in Wuhan, China, over 24 h between 8 AM February 2h and 8 AM February 27, 2020. The demographic information, clinical characteristics, vital signs, complications, laboratory values, and clinical managements of the patients were studied. RESULTS: A total of 226 patients were included. Their median (interquartile range, IQR) age was 64 (57-70) years, and 139 (61.5%) patients were male. The duration from the date of ICU admission to the study date was 11 (5-17) days, and the duration from onset of symptoms to the study date was 31 (24-36) days. Among all the patients, 155 (68.6%) had at least one coexisting disease, and their sequential organ failure assessment score was 4 (2-8). Organ function damages were found in most of the patients: ARDS in 161 (71.2%) patients, septic shock in 34 (15.0%) patients, acute kidney injury occurred in 57 (25.2%) patients, cardiac injury in 61 (27.0%) patients, and lymphocytopenia in 160 (70.8%) patients. Of all the studied patients, 85 (37.6%) received invasive mechanical ventilation, including 14 (6.2%) treated with extracorporeal membrane oxygenation (ECMO) at the same time, 20 (8.8%) received noninvasive mechanical ventilation, and 24 (10.6%) received continuous renal replacement therapy. By April 9, 2020, 87 (38.5%) patients were deceased and 15 (6.7%) were still in the hospital. CONCLUSIONS: Critically ill patients with COVID-19 are associated with a higher risk of severe complications and need to receive an intensive level of treatments. COVID-19 poses a great strain on critical care resources in hospitals. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2000030164. Registered on February 24, 2020, http://www.chictr.org.cn/edit.aspx?pid=49983&htm=4.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Cuidados Críticos , Surtos de Doenças , Unidades de Terapia Intensiva , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , Idoso , COVID-19 , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Prospectivos , Resultado do Tratamento
9.
Cell Mol Biol Lett ; 25: 20, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32206064

RESUMO

BACKGROUND: MiR-483-5p was recently identified as a risk factor in the early stages of acute myocardial infarction (AMI) patients. Here, we further investigated how miR-483-5p affects cardiomyocyte apoptosis and oxidative stress under hypoxic conditions. METHODS: Plasma samples were collected from AMI patients and healthy volunteers. The expression of miR-483-5p was determined using quantitative real-time PCR. An in vitro hypoxic model was constructed to mimic AMI in AC16 cells. Cell viability, apoptosis and oxidative stress biomarker levels (MDA, SOD and CAT) were respectively determined using CCK-8, flow cytometry and commercial assay kits. RESULTS: The expression levels of miR-483-5p were significantly higher in AMI patients than in control subjects. Circulating levels of miR-483-5p positively correlated with creatine kinase MB isoform (CK-MB) and cardiac troponin I (cTnI) levels. The in vitro experiments showed that the expression levels of miR-483-5p were also upregulated in hypoxia-induced AC16 cell injury. MiR-483-5p overexpression significantly increased hypoxia-induced cardiomyocyte apoptosis and oxidative stress, while knockdown attenuated these effects. Mechanistically, miR-483-5p directly targets MAPK3 in AC16 cells. Furthermore, the protective effects of miR-483-5p knockdown against hypoxia-induced cardiomyocyte injury are partially dependent on MAPK3. CONCLUSIONS: MiR-483-5p, which targets MAPK3, might be a potential therapeutic target for the diagnosis and prevention of hypoxia-induced myocardial injury.


Assuntos
Apoptose/genética , MicroRNAs/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Infarto do Miocárdio/sangue , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/genética , Idoso , Catalase/genética , Catalase/metabolismo , Hipóxia Celular , Sobrevivência Celular/genética , Creatina Quinase Forma MB/genética , Creatina Quinase Forma MB/metabolismo , Feminino , Humanos , Masculino , Malondialdeído/metabolismo , MicroRNAs/genética , Pessoa de Meia-Idade , Proteína Quinase 3 Ativada por Mitógeno/genética , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/genética , Infarto do Miocárdio/fisiopatologia , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Troponina T/genética , Troponina T/metabolismo , Regulação para Cima
10.
Clin Exp Pharmacol Physiol ; 47(8): 1429-1438, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32259311

RESUMO

The present study was conducted to determine whether atorvastatin reduces hypertension-induced vascular remodelling and whether its effects involve protein kinase D (PKD) and extracellular signal-regulated kinase 5 (ERK5). We used 16-week-old spontaneously hypertensive rats (SHRs) and age-matched Wistar-Kyoto (WKY) rats. The blood pressure and serum lipid concentration were measured. Changes in the vascular morphology and histology were examined using H&E, Masson' s trichrome, and Sirius Red staining. The media thickness (MT), ratio of MT to lumen diameter (LD) (MT/LD), collagen volume fraction (CVF) and hydroxyproline content were measured to evaluate vascular remodelling. Atorvastatin (50 mg/kg/day) was administered for 8 weeks. Increased blood pressure and vascular remodelling were more prominent in SHRs than in WKY rats. SHRs also had elevated PKD and ERK5 activation. The systolic blood pressure, MT/LD ratio, and hydroxyproline content were positively correlated with the activation level of PKD and ERK5 in SHRs. Atorvastatin significantly attenuated the activation of PKD and ERK5. Overall, this study demonstrated that atorvastatin could reverse vascular remodelling in SHRs. The PKD/ERK5 signalling pathway might be important for elucidating the beneficial pleiotropic effects of atorvastatin on vascular remodelling.


Assuntos
Atorvastatina/farmacologia , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Proteína Quinase C/metabolismo , Transdução de Sinais/efeitos dos fármacos , Remodelação Vascular/efeitos dos fármacos , Animais , Masculino , Ratos , Ratos Endogâmicos SHR
11.
Med Sci Monit ; 26: e925666, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32785210

RESUMO

BACKGROUND Atrial fibrillation (AF) often occurs in patients with acute myocardial infarction (AMI). This study aimed to observe the influence of different dosages of rosuvastatin on the prognosis of AMI patients with AF. MATERIAL AND METHODS We performed an observational, retrospective cohort study in Jinan, China, in which 323 AMI patients were recruited. All patients were randomized to receive optimal medication treatment and 10 mg or 20 mg of rosuvastatin. Holter monitor results, serum lipid levels, and heart function were recorded. We used multivariate Cox and Kaplan-Meier analyses to assess the independent factors and differences in AF and ischemia events and safety of rosuvastatin administered at different dosages. RESULTS TC, LDL-C, and TG at 1 and 12 months were significantly lower compared with those observed prior to treatment in both groups. The heart function of both groups was significantly improved after 12 months of treatment, especially in the 20 mg group. Multivariate Cox analysis showed that different dosages of rosuvastatin, age, smoking, drinking alcohol, and diabetes are independent factors related to the occurrence of AF and ischemic events. In addition, according to Kaplan-Meier analysis, no significant difference in adverse clinical events existed at different dosages of rosuvastatin. CONCLUSIONS Treatment with rosuvastatin can reduce the serum lipid level and improve cardiac function. Different dosages of rosuvastatin, age, smoking, drinking alcohol, and diabetes are independent risk factors for AF and ischemia events. The results suggested it is safe to use 20 mg rosuvastatin in the 12 months after hospital admission.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico , Rosuvastatina Cálcica/administração & dosagem , Idoso , Fibrilação Atrial/complicações , China , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Prognóstico , Estudos Retrospectivos , Rosuvastatina Cálcica/uso terapêutico
12.
Sensors (Basel) ; 20(24)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322417

RESUMO

Weld bead geometry features (WBGFs) such as the bead width, height, area, and center of gravity are the common factors for weighing welding quality control. The effective modeling of these WBGFs contributes to implementing timely decision making of welding process parameters to improve welding quality and enhance automatic levels. In this work, a dynamic modeling method of WBGFs is presented based on machine vision and learning in multipass gas metal arc welding (GMAW) with typical joints. A laser vision sensing system is used to detect weld seam profiles (WSPs) during the GMAW process. A novel WSP extraction method is proposed using scale-invariant feature transform and machine learning. The feature points of the extracted WSP, namely the boundary points of the weld beads, are identified with slope mutation detection and number supervision. In order to stabilize the modeling process, a fault detection and diagnosis method is implemented with cubic exponential smoothing, and the diagnostic accuracy is within 1.50 pixels. A linear interpolation method is presented to implement sub pixel discrimination of the weld bead before modeling WBGFs. With the effective feature points and the extracted WSP, a scheme of modeling the area, center of gravity, and all-position width and height of the weld bead is presented. Experimental results show that the proposed method in this work adapts to the variable features of the weld beads in thick plate GMAW with T-joints and butt/lap joints. This work can provide more evidence to control the weld formation in a thick plate GMAW in real time.

13.
Chemistry ; 25(2): 621-626, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30320475

RESUMO

Bimetallic sulfides with earth-abundant transition-metal elements are proposed to enhance the electrocatalytic activities. Further replacement of S atom by less electronegative P atom improves the electrocatalytic performance of OER and HER. Herein, hollow bimetallic zinc cobalt phosphosulfides (Zn0.3 Co2.7 S3 P) are synthesized by a two-step process. The optimal catalyst of Zn0.3 Co2.7 S3 P with particle size of 50 nm displays an excellent electroactivity and long-term durability toward efficient overall water splitting process in alkaline medium. The excellent bifunctional electrocatalytic performance may be ascribed to the synergistic effect of hollow structure, anion substitution tuning and unique size control.

14.
Chemistry ; 25(55): 12780-12788, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31265180

RESUMO

The development of efficient bifunctional electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) still remains a challenge in a wide range of renewable energy technologies. Herein, CuCo alloy nanoparticles encapsulated by nitrogen-doped carbonaceous nanoleaves (CuCo-NC) have been synthesized from a Cu(OH)2 /2D leaf-like zeolitic imidazolate framework (ZIF-L)-pyrolysis approach. Leaf-like Cu(OH)2 is first prepared by the ultrasound-induced self-assembly of Cu(OH)2 nanowires. The efficient encapsulation of Cu(OH)2 in ZIF-L is obtained owing to the morphology fitting between the leaf-like Cu(OH)2 and ZIF-L. CuCo-NC catalysts present superior electrocatalytic activity and stability toward ORR and OER over the commercial Pt/C and IrO2 , respectively, which are further used as bifunctional oxygen electrocatalysts in Zn-air batteries and exhibit impressive performance, with a high peak power density of 303.7 mW cm-2 , large specific capacity of up to 751.4 mAh g-1 at 20 mA cm-2 , and a superior recharge stability.

15.
Chemphyschem ; 20(22): 2964-2967, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31254312

RESUMO

Hierarchical hollow nanocubes based on ultra-thin CoFe-layered double hydroxide (CoFe-LDH) nanosheets have been prepared. The obtained CoFe-LDH hollow nanocubes could effectively catalyze water oxidation at a low overpotential of 270 mV @ 10 mA cm-2 , low Tafel slope of 58.3 mV dec-1 and show a long-term stability in alkali.

16.
Biochem Biophys Res Commun ; 503(3): 1450-1456, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30054042

RESUMO

Vascular disease can manifest as stenotic plaques or ectatic aneurysms. Human abdominal aortic aneurysms (AAA) comprise an inflammatory disease characterized by the predominance of T helper type 2 (Th2) cytokine expression. Leptin has been clearly demonstrated to play an important role in regulating Th0 cell to Th1. So, we hypothesize that leptin has a protective effect on aneurysm formation. In this study, we demonstrated that intraperitoneal injection of leptin attenuated Ang II-induced AAA formation in ApoE-/- mice with no effect on serum lipids and systolic blood pressure. To investigate the mechanisms involved, we found that leptin pretreatment exhibited decreased protein expression of matrix metalloproteinase 2 (MMP-2) and MMP-9 and increased transforming growth factor-ß1 (TGF-ß1). We also examined potential mechanism of leptin as a modulator of the immune response. Our results proved that pretreatment with leptin downregulated protein expression of Th2 cytokine IL-4 and mRNA levels of GATA-3, the key transcription factor for Th2 polarization, and upregulated Th1 cytokine INF-γ and T-bet, the key transcription factor for Th1 polarization. Taken together, leptin, with the effect of regulation of Th1/Th2 cytokines, may have therapeutic potential for the treatment of AAA. Leptin may constitute a novel therapeutic strategy to prevent AAA formation.


Assuntos
Angiotensina II/farmacologia , Aneurisma da Aorta Abdominal/metabolismo , Apolipoproteínas E/deficiência , Apolipoproteínas E/metabolismo , Leptina/metabolismo , Angiotensina II/administração & dosagem , Animais , Aneurisma da Aorta Abdominal/genética , Inflamação/metabolismo , Injeções Intraperitoneais , Leptina/administração & dosagem , Leptina/sangue , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/sangue , Proteínas Recombinantes/metabolismo , Linfócitos T/metabolismo , Células Th1
17.
Neural Plast ; 2018: 2160854, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29849553

RESUMO

We have synthesized hollow mesoporous silica (HMS) at a zeolitic imidazolate framework (ZIF) capsule that can be used as a drug delivery system for gentamicin (GM). The GM is first loaded into HMS. Then, the outer surface of the GM/HMS is coated with uniformed ZIF nanoparticles (denoted as GM/HMS@ZIF). The GM/HMS@ZIF has been successfully prepared and acts as a capsule for GM. The GM/HMS@ZIF shows a good biocompatibility and a good cellular uptake in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells. The GM is released slowly within 10 h under acidic conditions, which is used to simulate the pH of the endosome and lysosome compartments. The in vivo assay shows that the signal from fluorescein isothiocyanate (FITC) can be observed after 15 days, when the mice were injected with FITC/HMS@ZIF. This opens new opportunities to construct a delivery system for GM via one controlled low dose and sustained release for the therapy of Ménière's disease.


Assuntos
Antibacterianos/síntese química , Sistemas de Liberação de Medicamentos/métodos , Gentamicinas/síntese química , Imidazóis/síntese química , Dióxido de Silício/síntese química , Zeolitas/síntese química , Animais , Antibacterianos/administração & dosagem , Cápsulas , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/síntese química , Gentamicinas/administração & dosagem , Humanos , Imidazóis/administração & dosagem , Células MCF-7 , Camundongos , Dióxido de Silício/administração & dosagem , Zeolitas/administração & dosagem
18.
Angew Chem Int Ed Engl ; 57(40): 13187-13191, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30095856

RESUMO

The oxygen reduction reaction (ORR) is of significant importance in the development of fuel cells. Now, cobalt-nitrogen-doped chiral carbonaceous nanotubes (l/d-CCNTs-Co) are presented as efficient electrocatalysts for ORR. The chiral template, N-stearyl-l/d-glutamic acid, induces the self-assembly of well-arranged polypyrrole and the formation of ordered graphene carbon with helical structures at the molecular level after the pyrolysis process. Co was subsequently introduced through the post-synthesis method. The obtained l/d-CCNTs-Co exhibits superior ORR performance, including long-term stability and better methanol tolerance compared to achiral Co-doped carbon materials and commercial Pt/C. DFT calculations demonstrate that the charges on the twisted surface of l/d-CCNTs are widely separated; as a result the Co atoms are more exposed on the chiral CCNTs. This work gives us a new understanding of the effects of helical structures in electrocatalysis.

19.
J Cardiovasc Pharmacol ; 69(5): 305-313, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28207428

RESUMO

Myocarditis is a heterogeneous group of disorders defined by inflammation of the heart muscle with an excessively activated immune response. Numerous interventions have been investigated for the treatment of myocarditis while success is limited. Interleukin-37 (IL-37), a novel member of the IL-1 cytokine family, is a natural inhibitor of innate immunity associated with autoimmune diseases. However, the modulatory effect of IL-37 in myocarditis is unknown. In this study, we investigated the immunological regulation of IL-37 in the coxsackievirus B3-induced model of murine viral myocarditis. The results show that IL-37 significantly ameliorates the signs of myocarditis with increased survival rate and bodyweight, improved histological changes, reduced activities of MB isoenzyme of creatine kinase and cardiac troponin I, and a suppressed response of Th17 cells and enhanced response of regulatory T cells (Tregs) in the spleen. Moreover, IL-37 down-regulates the expression of Th17-related cytokines IL-6 and IL-17A, while promoting Treg-related cytokine IL-10 levels in the heart. Therefore, IL-37 may exhibit anti-inflammatory activity in the murine model of myocarditis by regulating the balance between Th17 and Treg cells, thereby providing a possible novel therapeutic target in myocarditis.


Assuntos
Anti-Inflamatórios/farmacologia , Infecções por Coxsackievirus/prevenção & controle , Enterovirus Humano B/patogenicidade , Interleucina-1/farmacologia , Miocardite/prevenção & controle , Miocárdio/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Animais , Infecções por Coxsackievirus/imunologia , Infecções por Coxsackievirus/virologia , Modelos Animais de Doenças , Enterovirus Humano B/imunologia , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Contração Miocárdica/efeitos dos fármacos , Miocardite/imunologia , Miocardite/virologia , Miocárdio/metabolismo , Miocárdio/patologia , Baço/efeitos dos fármacos , Baço/imunologia , Baço/metabolismo , Baço/virologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/virologia , Células Th17/imunologia , Células Th17/metabolismo , Células Th17/virologia , Fatores de Tempo , Função Ventricular Esquerda/efeitos dos fármacos
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