Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Water Res ; 259: 121851, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38851110

RESUMO

Overuse of antibiotics has led to their existence in nitrogen-containing water. The impacts of antibiotics on bio-denitrification and the metabolic response of denitrifiers to antibiotics are unclear. We systematically analyzed the effect of ciprofloxacin (CIP) on bio-denitrification and found that 5 mg/L CIP greatly inhibited denitrification with a model denitrifier (Paracoccus denitrificans). Nitrate reduction decreased by 32.89 % and nitrous oxide emission increased by 75.53 %. The balance analysis of carbon and nitrogen metabolism during denitrification showed that CIP exposure blocked electron transfer and reduced the flow of substrate metabolism used for denitrification. Proteomics results showed that CIP exposure induced denitrifiers to use the pentose phosphate pathway more for substrate metabolism. This caused a substrate preference to generate NADPH to prevent cellular damage rather than NADH for denitrification. Notably, despite denitrifiers having antioxidant defenses, they could not completely prevent oxidative damage caused by CIP exposure. The effect of CIP exposure on denitrifiers after removal of extracellular polymeric substances (EPS) demonstrated that EPS around denitrifiers formed a barrier against CIP. Fluorescence and infrared spectroscopy revealed that the binding effect of proteins in EPS to CIP prevented damage. This study shows that denitrifiers resist antibiotic stress through different intracellular and extracellular defense strategies.


Assuntos
Antibacterianos , Ciprofloxacina , Desnitrificação , Ciprofloxacina/farmacologia , Antibacterianos/farmacologia , Paracoccus denitrificans/metabolismo
2.
Appl Radiat Isot ; 210: 111361, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38815446

RESUMO

In the nuclear spectrum analysis processing, spectrum smoothing can remove the statistical fluctuation in the spectrum, which is beneficial for peak detection and peak area calculation. In this work, a spectrum smoothing algorithm is proposed based on digital Sallen-Key filter, which contains four parameters (m, n, k, D). The amplitude-frequency response curve of Sallen-Key filter is deduced and the filtering performance is analyzed. Meanwhile, the effects of the four parameters on the shape of the smoothed spectrum are explored: D affects the counts and peak areas of the spectrum, and the peak area can be corrected by the peak area correction function S'. The parameters of m, n and k affect the peak position after smoothing, making the peak position shift to the right, and the peak position correction function P' can be used to correct the peak position, when n¿2, the spectrum data appear negative after smoothing, when k¿2, the smoothed spectrum broadening degree is greater than 20%. Smoothness (R), noise smoothing factor (NSF), spectrum count ratio before and after smoothing (PER), and comprehensive evaluation factor (Q) are used to evaluate the smoothing effect of the algorithm. The parameters of the algorithm are optimally selected: about the gamma spectrum of 137Cs and 60Co, the optimal parameters are m=1.5 n=2 k=2 D=1, about the characteristic X-ray spectrum of Fe and quasi-geological sample (TiMnFeNiCuZn), the optimal parameters are m=1.1 n=1.1 k=1.3 D=1. Based on Sallen-Key smoothing method, Fourier transform method, Gaussian function method, wavelet transformation method, center of gravity method and least squares method, the gamma spectrum of 137Cs is smoothed and denoised in this paper. The results show that the Sallen-Key method has better spectrum denoising effect (R=0.6056) and comprehensive performance indicators (Q=0.6104), which can be further applied for the smoothing of nuclear spectrum data.

3.
Bioresour Technol ; 379: 129039, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37037332

RESUMO

A highly efficient aerobic denitrifying microbe was isolated from sewage sludge by using a denitrifier enrichment strategy based on decreasing carbon content. The microbe was identified as Pseudomonas mendocina HITSZ-D1 (hereafter, D1). Investigation of the conditions under which D1 grew and denitrified revealed that it performed good growth and nitrate removal performance under a wide range of conditions. In particular, D1 rapidly removed all types of inorganic nitrogen without accumulation of the intermediate products nitrite and nitrous oxide. Overall, D1 showed a total nitrogen removal efficiency >96% at a C/N ratio of 8. The biotransformation modes and fates of three typical types of inorganic nitrogen were also assessed. Moreover, D1 had significantly higher denitrification efficiency and enzyme activities than other aerobic denitrifying microbes (Paracoccus denitrificans, Pseudomonas aeruginosa, and Pseudomonas putida). These results suggest that D1 has great potential for treating wastewater containing high concentrations of nitrogen.


Assuntos
Nitritos , Pseudomonas mendocina , Nitritos/metabolismo , Pseudomonas mendocina/metabolismo , Esgotos , Desnitrificação , Nitratos/metabolismo , Nitrogênio/metabolismo , Nitrificação , Aerobiose
4.
Environ Res ; 221: 115218, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36608761

RESUMO

The regulation of bacterial quorum sensing (QS) has been used to inhibit biofouling in wastewater treatment plants and the formation of biofilms. In contrast to traditional QS regulation strategies, this study aimed to obstruct the transmembrane transport process of QS signals to decrease their extracellular accumulation. Three phytochemicals, astragaloside IV, eugenol, and baicalin were selected, their effects on biofilm formation by Pseudomonas aeruginosa PA14 were studied, and the mechanisms determined. The inhibition efficiency of biofilm formation by 50 mg/L astragaloside IV, 1 mg/L eugenol, and 1 mg/L baicalin were 37%, 26%, and 26%, respectively. Confocal laser scanning microscopy and analysis of extracellular polymeric substances indicated that the three inhibitors affected the structure and composition of the biofilms. Furthermore, bacterial motility and a variety of QS-related virulence factors were suppressed by the inhibitor treatment due to changes in bacterial QS. Notably, the three inhibitors all decreased the extracellular concentration of the QS signaling molecule 3-oxo-C12-homoseine lactone by affecting the function of efflux pump MexAB-OprM. This indirectly interfered with the bacterial QS system and thus inhibited biofilm formation. In conclusion, this study revealed the inhibitory effects and inhibition mechanism of three phytochemicals on efflux pump and QS of P. aeruginosa and realized the inhibition on biofilm formation. We update the efflux pump inhibitor library and provide a new way for biofilm contamination control.


Assuntos
Percepção de Quorum , Saponinas , Eugenol/farmacologia , Biofilmes , Saponinas/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias
5.
Environ Sci Technol ; 56(19): 14048-14058, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36074547

RESUMO

Current research has widely applied heteroatom doping for the promotion of catalyst activity in peroxymonosulfate (PMS) systems; however, the relationship between heteroatom doping and stimulated activation mechanism transformation is not fully understood. Herein, we introduce nitrogen and sulfur doping into a Co@rGO material for PMS activation to degrade tetracycline (TC) and systematically investigate how heteroatom doping transformed the activation mechanism of the original Co@rGO/PMS system. N was homogeneously inserted into the reduced graphene oxide (rGO) matrix of Co@rGO, inducing a significant increase in the degradation efficiency without affecting the activation mechanism transformation. Additionally, S doping converted Co3O4 to Co4S3 in Co@rGO and transformed the cooperative oxidation pathway into a single non-radical pathway with stronger intensity, which led to a higher stability against environmental interferences. Notably, based on density functional theory (DFT) calculations, we demonstrated that Co4S3 had a higher energy barrier for PMS adsorption and cleavage than Co3O4, and therefore, the radical pathway was not easily stimulated by Co4S3. Overall, this study not only illustrated the improvement due to the heteroatom doping of Co@rGO for TC degradation in a PMS system but also bridged the knowledge gap between the catalyst structure and degradation performance through activation mechanism transformation drawn from theoretical and experimental analyses.


Assuntos
Nitrogênio , Peróxidos , Antibacterianos , Cobalto , Grafite , Nitrogênio/química , Óxidos , Peróxidos/química , Enxofre , Tetraciclina
6.
Appl Radiat Isot ; 186: 110277, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35609402

RESUMO

The Gaussian filter shaping circuit is widely used in the nuclear pulse signal processing due to its good performance in amplitude extraction and pulse counting. A third-order Sallen-Key (3rd S-K) filter shaping circuit is designed based on a RC integrator and a second-order Sallen-Key (2nd S-K) circuit. According to the digital 3rd S-K, the transfer functions is derived in the Laplacian domain, and the numerical recurrence model is analyzed and researched, the purpose is to obtain its transfer function and amplitude-frequency response curve in the z-domain. For the simulation and actual sampling of the nuclear signal, digital shaping processing is performed at different parameters, three parameters (d, SNR, δ) are defined to compare and analyze the amplitude extraction, noise suppression and symmetry of the digital shaping method, which shows that as the shaping parameters increases, the digital shaping output noise suppression performance is better, the SNR increased from 49.25 to 64.21, the waveform is more symmetrical, the δ reduced from 34.05 to 0.22. At the same parameters, it is compared and analyzed with CR-RC3 and 2nd S-K shaping methods, according to the digital Gaussian shaping results, the 3rd S-K digital shaping method has better pulse amplitude extraction(d = 36.06%), noise suppression performance (SNR = 64.21) and waveform symmetry (δ = 0.22). Under different shaping methods, the energy resolution and pulse counting rate of the Fe characteristic X-ray energy spectrum are compared based on a Si-PIN detector. The results show that the 3rd S-K digital shaping method has better energy resolution performance and comprehensive performance indicators, which can be further applied for digital shaping of nuclear pulse signals.

7.
EBioMedicine ; 78: 103968, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35367772

RESUMO

Myocardial infarction is lethal to patients because of insufficient blood perfusion to vital organs. Several attempts have been made to improve its prognosis, among which nanomaterial research offers an opportunity to address this problem at the molecular level and has the potential to improve disease prevention, diagnosis, and treatment significantly. Up to now, nanomaterial-based technology has played a crucial role in broad novel diagnostic and therapeutic strategies for cardiac repair. This review summarizes various nanomaterial applications in myocardial infarction from multiple aspects, including high precision detection, pro-angiogenesis, regulating immune homeostasis, and miRNA and stem cell delivery vehicles. We also propose promising research hotspots that have not been reported much yet, such as conjugating pro-angiogenetic elements with nanoparticles to construct drug carriers, developing nanodrugs targeting other immune cells except for macrophages in the infarcted myocardium or the remote region. Though most of those strategies are preclinical and lack clinical trials, there is tremendous potential for their further applications in the future.


Assuntos
Infarto do Miocárdio , Nanopartículas , Portadores de Fármacos , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/terapia , Miocárdio , Células-Tronco/fisiologia
8.
J Hazard Mater ; 424(Pt A): 127247, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34879542

RESUMO

Current research focused on developing multiple active species in peroxymonosulfate (PMS) system to degrade contaminants, but deepening concern lacks over why cooperation of those active species facilitated a faster degradation. Here, we employed Co3O4, rGO and Co3O4@rGO composite to activate PMS for tetracycline (TC) degradation, and detected crucial factors toward highest performance of Co3O4@rGO/PMS system. Batch experiments exhibited a satisfactory TC degradation efficiency under Co3O4@rGO/PMS, complete degraded 50 mg/L TC within 20 min. Analytical tests discovered that radical active species generated by Co3O4/PMS and non-radical species by rGO/PMS were successfully co-existed in Co3O4@rGO/PMS system, significantly improving the performance of TC removal. Subsequently, a combination of density functional theory (DFT) calculation and intermediates analysis revealed that, in Co3O4@rGO/PMS system, the cooperation rather than independent effect of radical and non-radical active species expanded TC degradation pathways, enhancing the degradation performance. Furthermore, decent adaptability, stability, and recyclability toward affecting factors variation of Co3O4@rGO/PMS demonstrated it as a potent and economical system to degrade TC. Overall, this study developed a novel Co3O4@rGO/PMS system with a cooperative oxidation pathway for highly efficient TC removal, and managed to clarify why this oxidation pathway achieved high efficiency through a combination of theoretical and experimental method.


Assuntos
Peróxidos , Tetraciclina , Cobalto , Óxidos
9.
Adv Ther ; 38(5): 2302-2314, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33740217

RESUMO

INTRODUCTION: This study was designed to understand the baseline salt intake of adult patients with hypertension in Shanxi Province, and to analyze the correlation between urinary sodium excretion and blood pressure. METHODS: From June 2018 to December 2019, 16 hospitals with regional representativeness and experimental conditions in Shanxi Province were selected, and 643 eligible adult inpatients with primary hypertension were enrolled from these hospitals. The ages of patients ranged from 18 to 80 years. A 24-h ambulatory blood pressure monitoring was performed, and morning urine sodium concentration and 24-h urine sodium excretion were measured. The correlation between urinary sodium excretion and blood pressure in adult patients with hypertension was analyzed. RESULTS: The baseline salt intake of the adult patient participants with hypertension in Shanxi Province was 11.51 g/day. The average 24-h urinary sodium excretion of all observed subjects was 191.90 ± 98.18 mmol. The 24-h urinary sodium excretion and morning urinary sodium concentration were significantly positively correlated with systolic and diastolic blood pressure following adjustment of confounding factors, including gender, age, body weight, and smoking. CONCLUSION: The morning urine sodium concentration and 24-h urine sodium excretion were significantly positively correlated with blood pressure. High sodium excretion may be a risk factor for rhythm abnormalities in non-dipper pattern blood pressure. The control of urinary sodium concentration can thus be an important strategy for regulating abnormal blood pressure rhythm.


Assuntos
Hipertensão , Sódio , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
10.
AMB Express ; 10(1): 159, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32869156

RESUMO

In the era of increased antibiotic resistance and ever-stricter control on antibiotic use, it is urgent to develop green, safe, and non-residue alternatives to antibiotics applied to the poultry industry. To this end, we supplied the potential Lactobacillus plantarum (L. plantarum) fermented Astragalus in the diet of laying hens, with a final addition of 3‰. Its effects have been assessed on laying performance, egg quality, antioxidant and immunological status, and intestinal microbiota, and are compared to the control group, to the Astragalus group containing 3‰ unfermented Astragalus, and to the L. plantarum group containing 2% L. plantarum [5 × 108 colony-forming unit (CFU) per milliliter (mL)]. During the second half of the experimental period (15 to 28 days), the egg production rate was considerably higher in the fermented Astragalus group than that in the other groups, with the fermented Astragalus group having the lowest feed conversion ratio. No significant difference (P > 0.05) was noted among treatments on egg quality. Fermented Astragalus-treated hens exhibited significantly increased catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in serum, and reduced malondialdehyde (MDA) in serum. Furthermore, fermented Astragalus supplementation resulted in a significant increase in ileal microbiota abundance relative to control. In conclusion, feeding laying hens with L. plantarum fermented Astragalus has beneficial effects on production, antioxidant potential, immunity, and ileal microbiota. L. plantarum fermented Astragalus is expected to be a novel feed additive used in poultry production.

12.
J Cell Mol Med ; 22(3): 1708-1719, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29314656

RESUMO

Pathological cardiac hypertrophy aggravated myocardial infarction and is causally related to autophagy dysfunction and increased oxidative stress. Rapamycin is an inhibitor of serine/threonine kinase mammalian target of rapamycin (mTOR) involved in the regulation of autophagy as well as oxidative/nitrative stress. Here, we demonstrated that rapamycin ameliorates myocardial ischaemia reperfusion injury by rescuing the defective cytoprotective mechanisms in hypertrophic heart. Our results showed that chronic rapamycin treatment markedly reduced the phosphorylated mTOR and ribosomal protein S6 expression, but not Akt in both normal and aortic-banded mice. Moreover, chronic rapamycin treatment significantly mitigated TAC-induced autophagy dysfunction demonstrated by prompted Beclin-1 activation, elevated LC3-II/LC3-I ratio and increased autophagosome abundance. Most importantly, we found that MI/R-induced myocardial injury was markedly reduced by rapamycin treatment manifested by the inhibition of myocardial apoptosis, the reduction of myocardial infarct size and the improvement of cardiac function in hypertrophic heart. Mechanically, rapamycin reduced the MI/R-induced iNOS/gp91phox protein expression and decreased the generation of NO and superoxide, as well as the cytotoxic peroxynitrite. Moreover, rapamycin significantly mitigated MI/R-induced endoplasmic reticulum stress and mitochondrial impairment demonstrated by reduced Caspase-12 activity, inhibited CHOP activation, decreased cytoplasmic Cyto-C release and preserved intact mitochondria. In addition, inhibition of mTOR also enhanced the phosphorylated ERK and eNOS, and inactivated GSK3ß, a pivotal downstream target of Akt and ERK signallings. Taken together, these results suggest that mTOR signalling protects against MI/R injury through autophagy induction and ERK-mediated antioxidative and anti-nitrative stress in mice with hypertrophic myocardium.


Assuntos
Cardiomegalia/complicações , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Autofagia/efeitos dos fármacos , Imunossupressores/farmacologia , Masculino , Camundongos , Traumatismo por Reperfusão Miocárdica/complicações , Traumatismo por Reperfusão Miocárdica/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
13.
Acta Pharmacol Sin ; 39(2): 205-212, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28933424

RESUMO

Dual antiplatelet therapy (DAT) with aspirin and clopidogrel is the standard regimen to achieve rapid platelet inhibition and prevent thrombotic events. Currently, little information is available regarding alternative antiplatelet therapy in patients with an allergy or intolerance to aspirin. Although cilostazol is already a common alternative to aspirin in clinical practice in China, its efficacy and safety remain to be determined. We retrospectively analyzed 613 Chinese patients who had undergone primary percutaneous coronary intervention (PCI). Among them, 405 patients received standard DAT (aspirin plus clopidogrel) and 205 patients were identified with intolerance to aspirin and received alternative DAT (cilostazol plus clopidogrel). There were no significant differences between the two groups in their baseline clinical characteristics. The main outcomes of the study included major adverse cardiac events (MACEs) and bleeding events during 12 months of follow-up. The MACEs endpoint was reached in 10 of 205 patients treated with cilostazol (4.9%) and in 34 of 408 patients treated with aspirin (8.3%). No statistically significant difference was observed in MACEs between the two groups. However, patients in the cilostazol group had less restenosis than did patients in the aspirin group (1.5% vs 4.9%, P=0.035). The occurrence of bleeding events tended to be lower in the cilostazol group (0.49% vs 2.7%, P=0.063). These clinical observations were further analyzed using network system pharmacology analysis, and the outcomes were consistent with clinical observations and preclinical data reports. We conclude that in Chinese patients with aspirin intolerance undergoing coronary stent implantation, the combination of clopidogrel with cilostazol may be an efficacious and safe alternative to the standard DAT regimen.


Assuntos
Aspirina/efeitos adversos , Stents Farmacológicos , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária/uso terapêutico , Tetrazóis/uso terapêutico , Ticlopidina/análogos & derivados , Idoso , Povo Asiático , China , Cilostazol , Clopidogrel , Reestenose Coronária/prevenção & controle , Interpretação Estatística de Dados , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Simulação de Acoplamento Molecular , Inibidores da Agregação Plaquetária/administração & dosagem , Estudos Retrospectivos , Tetrazóis/administração & dosagem , Ticlopidina/administração & dosagem , Ticlopidina/uso terapêutico
14.
Clin Sci (Lond) ; 132(1): 93-110, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29175946

RESUMO

Left ventricular hypertrophy (LVH) is causally related to increased morbidity and mortality following acute myocardial infarction (AMI) via still unknown mechanisms. Although rapamycin exerts cardioprotective effects against myocardial ischemia/reperfusion (MI/R) injury in normal animals, whether rapamycin-elicited cardioprotection is altered in the presence of LVH has yet to be determined. Pressure overload induced cardiac hypertrophied mice and sham-operated controls were exposed to AMI by coronary artery ligation, and treated with vehicle or rapamycin 10 min before reperfusion. Rapamycin produced marked cardioprotection in normal control mice, whereas pressure overload induced cardiac hypertrophied mice manifested enhanced myocardial injury, and was refractory to rapamycin-elicited cardioprotection evidenced by augmented infarct size, aggravated cardiomyocyte apoptosis, and worsening cardiac function. Rapamycin alleviated MI/R injury via ERK-dependent antioxidative pathways in normal mice, whereas cardiac hypertrophied mice manifested markedly exacerbated oxidative/nitrative stress after MI/R evidenced by the increased iNOS/gp91phox expression, superoxide production, total NO metabolites, and nitrotyrosine content. Moreover, scavenging superoxide or peroxynitrite by selective gp91phox assembly inhibitor gp91ds-tat or ONOO- scavenger EUK134 markedly ameliorated MI/R injury, as shown by reduced myocardial oxidative/nitrative stress, alleviated myocardial infarction, hindered cardiomyocyte apoptosis, and improved cardiac function in aortic-banded mice. However, no additional cardioprotective effects were achieved when we combined rapamycin and gp91ds-tat or EUK134 in ischemic/reperfused hearts with or without LVH. These results suggest that cardiac hypertrophy attenuated rapamycin-induced cardioprotection by increasing oxidative/nitrative stress and scavenging superoxide/peroxynitrite protects the hypertrophied heart from MI/R.


Assuntos
Hipertrofia Ventricular Esquerda/fisiopatologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Estresse Oxidativo/fisiologia , Sirolimo/farmacologia , Animais , Cardiotônicos/farmacologia , Resistência a Medicamentos , Sequestradores de Radicais Livres/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Compostos Organometálicos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Salicilatos/farmacologia
15.
Shock ; 47(3): 363-369, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27559699

RESUMO

Remote ischemic preconditioning (RIPC) is one of the most powerful intrinsic cardioprotective strategies discovered so far and experimental data indicate that comorbidity may interfere with the protection by RIPC. Therefore, we investigate whether RIPC-induced cardioprotection was intact in hypercholesterolemic rat hearts exposed to ischemia reperfusion in vivo. Normal or hypercholesterolemic rat hearts were exposed to 30 min of ischemia and 2 h of reperfusion, with or without RIPC, PI3K inhibitor wortmannin, MEK-ERK1/2 inhibitor PD98059, GSK3ß inhibitor SB216763. Infarct size, apoptosis, MG53, PI3K-p85, p-Akt, p-ERK1/2, p-GSK3ß, and cleaved Caspase-3 were determined. RIPC reduced infarct size, limited cardiomyocyte apoptosis following IR that was blocked by wortmannin but not PD98059. RIPC triggered unique cardioprotective signaling including MG53, phosphorylation of Akt, and glycogen synthase kinase-3ß (GSK3ß) in concert with reduced proapoptotic active caspase-3. In contrast, RIPC failed to reduce myocardial necrosis and apoptosis as well as to increase the phosphorylated Akt and GSK3ß in hypercholestorolemic myocardium. Importantly, we found that inhibition of GSK with SB216763 reduced myocardial infarct size in healthy and hypercholesterolemic hearts, but no additional cardioprotective effect was achieved when combined with RIPC. Our results suggest that acute GSK3ß inhibition may provide a novel therapeutic strategy for hypercholesterolemic patients during acute myocardial infarction, whereas RIPC is less effective due to signaling events that adversely affect GSK3ß.


Assuntos
Hipercolesterolemia/complicações , Hipercolesterolemia/enzimologia , Precondicionamento Isquêmico , Fosfatidilinositol 3-Quinases/metabolismo , Androstadienos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/metabolismo , Masculino , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Wortmanina
16.
Mar Drugs ; 14(12)2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27999379

RESUMO

Doxorubicin (DOX) is a highly potent chemotherapeutic agent, but its usage is limited by dose-dependent cardiotoxicity. DOX-induced cardiotoxicity involves increased oxidative stress and activated endoplasmic reticulum-mediated apoptosis. Alginate oligosaccharide (AOS) is a non-immunogenic, non-toxic and biodegradable polymer, with anti-oxidative, anti-inflammatory and anti-endoplasmic reticulum stress properties. The present study examined whether AOS pretreatment could protect against acute DOX cardiotoxicity, and the underlying mechanisms focused on oxidative stress and endoplasmic reticulum-mediated apoptosis. We found that AOS pretreatment markedly increased the survival rate of mice insulted with DOX, improved DOX-induced cardiac dysfunction and attenuated DOX-induced myocardial apoptosis. AOS pretreatment mitigated DOX-induced cardiac oxidative stress, as shown by the decreased expressions of gp91 (phox) and 4-hydroxynonenal (4-HNE). Moreover, AOS pretreatment significantly decreased the expression of Caspase-12, C/EBP homologous protein (CHOP) (markers for endoplasmic reticulum-mediated apoptosis) and Bax (a downstream molecule of CHOP), while up-regulating the expression of anti-apoptotic protein Bcl-2. Taken together, these findings identify AOS as a potent compound that prevents acute DOX cardiotoxicity, at least in part, by suppression of oxidative stress and endoplasmic reticulum-mediated apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Cardiotoxicidade/prevenção & controle , Doxorrubicina/farmacologia , Oligossacarídeos/farmacologia , Aldeídos/metabolismo , Alginatos , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores , Cardiotoxicidade/metabolismo , Cardiotoxicidade/patologia , Caspase 12/metabolismo , Cromatografia Líquida de Alta Pressão , Doxorrubicina/efeitos adversos , Doxorrubicina/química , Doxorrubicina/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Ácido Glucurônico , Ácidos Hexurônicos , Camundongos , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Receptores Imunológicos/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Fator de Transcrição CHOP/metabolismo
18.
Int J Cardiol ; 214: 393-7, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27085653

RESUMO

BACKGROUND: Second-generation drug-eluting stents (DESs) have become increasingly popular devices for patients with saphenous vein graft (SVG) disease. Second-generation DESs were designed to have more safety and efficacy than first-generation DES, but clinical outcomes in SVG disease remain conflicting. METHODS AND RESULTS: Randomized controlled trials (RCTs) were identified when comparing second- versus first-generation DESs in SVG disease. The main endpoint was all-cause death. The time of follow-up was at least 30days. The secondary endpoints were major adverse cardiovascular events (MACEs), target vessel revascularization (TVR), target lesion revascularization (TLR), myocardial infarction (MI), and stent thrombosis. These endpoints were assessed at 30days, 12months and 24months. Four RCTs with 1077 SVG patients undergoing the implantation of DES were collected in the current meta-analysis. As a result, second-generation DES-treated patients had the significantly lower MACE rates at 12months (P=0.03; OR: 0.69, 95% CI: 0.49,0.97). No differences in two groups were seen in all-cause death, MI, TVR, stent thrombosis and TLR. CONCLUSIONS: Our limited evidence indicated that, second-generation DES in SVG patients, compared with first-generation DES, offered similar levels of safety, but were more effective than the former one.


Assuntos
Doença da Artéria Coronariana/terapia , Stents Farmacológicos/efeitos adversos , Revascularização Miocárdica/métodos , Veia Safena/transplante , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/mortalidade , Humanos , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Trombose/epidemiologia , Trombose/etiologia , Resultado do Tratamento
19.
Gut Liver ; 10(3): 456-63, 2016 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-26419236

RESUMO

BACKGROUND/AIMS: The recognition of a correlation between patatin-like phospholipase domain containing-protein 3 (PNPLA3) rs738409 (C>G) and the severity of liver steatosis or fibrosis in chronic hepatitis C (CHC) has not reached a consensus. This meta-analysis sought to investigate with accuracy the association between the PNPLA3 rs738409 (C>G) polymorphism and liver steatosis and advanced fibrosis in CHC patients. METHODS: We performed a comprehensive literature search from the PubMed, Embase, Web of Science, and Google Scholar databases up to December 31, 2014. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Statistical analyses were performed using Stata 12.0 software. RESULTS: The meta-analysis revealed the severity of liver fibrosis was significantly higher in CHC patients with PNPLA3 rs738409 GG in Caucasians (versus CC+CG OR, 2.29; 95% CI, 1.57 to 3.35; p<0.05) but not Asian populations. In Caucasians, liver steatosis was also more severe in CHC patients with rs738409 GG (versus CC+CG; OR, 4.33; 95% CI, 2.59 to 7.22; p<0.05). The sensitivity analysis indicated the results of this meta-analysis were stable and no publication bias was detected. CONCLUSIONS: PNPLA3 rs738409 (C>G) was associated with the risk of both advanced liver fibrosis and steatosis in patients with CHC, especially among Caucasian populations.


Assuntos
Fígado Gorduroso/genética , Hepatite C Crônica/genética , Lipase/genética , Cirrose Hepática/genética , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único , Povo Asiático/genética , Humanos , População Branca/genética
20.
J Am Heart Assoc ; 4(11)2015 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-26553212

RESUMO

BACKGROUND: Several studies have indicated that chronic kidney disease is independently associated with the presence of left ventricular hypertrophy (LVH). However, little clinical data are currently available regarding the detailed correlation between LVH and renal function in elderly patients with non-end-stage renal disease. METHODS AND RESULTS: A total of 300 in- and outpatients (more than 60 years of age, non-end-stage renal disease), 251 with LVH and 49 without LVH, seen at Beijing Friendship Hospital from January 2000 to December 2010 were included in this retrospective study. One observation period of 12 months was used to detect rapid kidney function decline. The evaluations of cardiac structure and function were performed via echocardiography. The multivariable logistic analysis showed patients with LVH had a much higher risk of rapid kidney function decline than those without LVH. Additionally, the baseline left ventricular mass index was 140 (125-160) g/m(2) in the non-chronic kidney disease group, 152 (130-175) g/m(2) in the mild chronic kidney disease group (estimated glomerular filtration rate (eGFR)≥60 ml/min/1.73 m(2)), and 153 (133-183) g/m(2) in the severe chronic kidney disease group (eGFR<60 ml/min/1.73 m(2)), with a significant difference (P=0.009). CONCLUSIONS: Our data demonstrate that a high rate of renal function decline contributes to pathological LVH in non-end-stage renal disease elderly patients and that LVH is positively associated with renal function decline followed by an increased risk of rapid kidney function decline.


Assuntos
Taxa de Filtração Glomerular , Hipertrofia Ventricular Esquerda/complicações , Rim/fisiopatologia , Insuficiência Renal Crônica/complicações , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , China , Progressão da Doença , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Modelos Logísticos , Masculino , Análise Multivariada , Razão de Chances , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Ultrassonografia , Remodelação Ventricular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...