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1.
Dokl Biochem Biophys ; 497(1): 137-143, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33895930

RESUMO

Diabetes mellitus (DM), a metabolic disorder, is the causes of oxidative stress leading to complications in micro- and macro-vascular system. The present study investigated sophocarpine for anti-diabetic potential in vivo in mice model. Sophocarpine administration to diabetic mice significantly (p < 0.05) attenuated glucose content in the plasma. The diabetes mediated lowering of GSH, ceruloplasmin and vitamin E was prevented in mice plasma by sophocarpine administration. Sophocarpine significantly (p < 0.05) reversed diabetes mediated suppression of insulin level and total Hb content in the mice plasma. In sophocarpine administrated diabetic mice C-peptide level was elevated and glycosylated hemoglobin content was suppressed significantly (p < 0.05) relative to diabetic group. Administration of sophocarpine significantly (p < 0.05) repressed diabetes mediated increase in TG and TC levels in dose-based manner. Administration of sophocarpine exhibited preventive role against diabetes mediated pathological damage to pancreas in the mice. Sophocarpine administration to diabetic mice repressed PPARγ recruitment significantly (p < 0.05) in dose-dependent manner. Sophocarpine prevents oxidative stress mediated pancreatic damage through increase in vitamin E, GSH and C-peptide levels, Moreover, the PPARγ activity was down-regulated, LDL-c content lowered and HDL-c level elevated in diabetic mice by sophocarpine. Therefore, sophocarpine may be developed for treatment of diabetes, however, further in vivo studies need to confirm the same.


Assuntos
Alcaloides/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Alcaloides/uso terapêutico , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Progressão da Doença , Relação Dose-Resposta a Droga , Hipoglicemiantes/uso terapêutico , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos
2.
Nanotechnology ; 29(39): 395501, 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-29956679

RESUMO

In situ dynamic temperature mapping of photothermally heated aluminum nanoparticles (Al NPs) embedded in a fluoropolymer (THV) is achieved using fluorescent dye (rhodamine 6G). A plasmonic grating substrate enhances the dye fluorescence intensity by a factor of seven over a glass substrate, to enable image capture rates of 500 frames per second. Further, the fluorescence intensity is linearly related to temperature and reversible. Photothermal heating of embedded Al NPs using a 2380 W cm-2 incident flux produced an Al NP heating rate of 1.2 × 104 °C s-1. Localized Al NP motion was also observed and attributed to thermal expansion and melting of the polymer. Multiphysics simulation provided agreement with experimental observations, bolstering confidence in the technique. The plasmonic grating platforms were shown to significantly improve both fluorescence intensity and the photothermal heating of Al compared to glass substrates, opening a new path for fast and high-resolution in situ temperature mapping.

3.
Nanotechnology ; 26(35): 355204, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26267227

RESUMO

Single-electron transistors incorporating single ∼1 nm gold nanocluster (AuNCs) and pentacene as a complex charge transport system have been used to study the quantum Coulomb blockade and its single electron tunnelling behaviour at room temperature (RT) (300 K). Monodisperse ultra-small (0.86 ± 0.30 nm) AuNCs were deposited by the tilted-target sputtering technique into 12 nm nanogaps fabricated by high-resolution e-beam lithography. Tunnelling resistance was modulated to ∼10(9) Ω by addition of a pentacene layer, allowing clear observation of quantum staircases and Coulomb oscillations with on/off current modulation ratio of ∼100 in RT current-voltage measurements. The electron addition energy and average quantized energy level spacing were found to be 282 and 80.4 meV, respectively, which are significantly larger than the thermal energy at 300 K (25.9 meV).

4.
Quant Imaging Med Surg ; 13(3): 1563-1576, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36915301

RESUMO

Background: Due to the uncertainty of the success of percutaneous coronary intervention (PCI) and the complexity of selecting suitable treatment cases, the interventional outcome of coronary chronic total occlusion (CTO) remains challenging. The purpose of this study was to evaluate the role of quantitative plaque analysis based on coronary computed tomography angiography (CCTA) in predicting the CTO-PCI outcome. Methods: We retrospectively included 78 patients with CTO (80 lesions) confirmed by invasive coronary angiography from July 2016 to December 2018. All patients underwent PCI treatment according to standard practice. A total of 47 lesions in 47 patients were successfully treated with PCI. PCI failed in the remaining 33 lesions in 31 patients. The following conventional CCTA morphologic parameters were evaluated and compared between the PCI-success and PCI-failure groups: stump morphology; occlusion length, tortuous course; CTO lesion calcium; bridging collateral vessel; retrograde collateral vessel; the appearance of the occluded distal segment; and quantitative CTO plaque characteristics, including total plaque volume, calcified plaque (CP) volume, noncalcified plaque (NCP) volume, low-density noncalcified plaque (LDNCP) volume, and plaque length. Univariate and multivariate logistic regression analyses were performed to determine independent parameters predictive of CTO-PCI outcomes. The predictive performances were assessed using receiver operating characteristic curve analysis. Results: The blunt stump was the only independent CCTA morphologic parameter to predict the outcome of CTO-PCI [odds ratio (OR): 10.807; P<0.001]. NCP volume (OR: 1.018; P<0.001), CP volume (OR: 1.026; P=0.049), and plaque length (OR: 1.058; P=0.037) were independent quantitative CTO plaque characteristics predictive of CTO-PCI outcomes. The plaque-based model combining NCP volume with CP volume and plaque length had a higher area under the curve (AUC =0.96) than did the morphology-based model that included blunt stump (AUC 0.68) in predicting the outcomes of CTO-PCI (P<0.001). Conclusions: The CCTA-based plaque characteristics, including NCP volume, CP volume, and plaque length, outperformed morphologic parameters in predicting the CTO-PCI outcomes.

5.
Int J Ophthalmol ; 15(6): 905-913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814903

RESUMO

AIM: To investigate the effects of curcumin (Cur) nanoparticles loaded with chitosan derivatives grafted by deoxycholic acid (Chit-DC) on human retinal pigment epithelial (hRPE) cell proliferation and vascular endothelial growth factor (VEGF) mRNA expression. METHODS: Cur nanoparticles were synthesized with Chit-DC as the carrier and Cur as the supported drug. Cell counting kit-8 (CCK-8) method was used to detect the effects of different concentrations of Cur/Chit-DC, Chit-DC, and Cur on the proliferation of hRPE cells for different times. The changes of Cur/Chit-DC and Cur on hRPE cell cycle were determined by flow cytometry. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA expression levels of VEGF in hRPE cells treated with Cur, Chit-DC and Cur/Chit-DC at 10 µg/mL for 24h. RESULTS: Different concentrations of Chit-DC nanoparticle treated hRPE cells had no significant difference in terms of optical density (OD) values compared with the control group at 24h and 48h. Moreover, there was no change in the cell morphology under a light microscope. After 24h treatment with Cur/Chit-DC and Cur, the percentage of G0-G1 phase cells increased and the percentage of S phase cells decreased in all concentration groups. Cur/Chit-DC and Cur in all concentration groups inhibited the proliferation of hRPE cells in a time and dose dependent manner, and reduced the expression level of VEGF mRNA. CONCLUSION: The Cur/Chit-DC nanoparticles can release Cur continuously and have sustained release function. Both Cur/Chit-DC nanoparticles and Cur could inhibit hRPE cells cultured in vitro, and could reduce the expression level of VEGF mRNA in hRPE cells.

6.
Sci Total Environ ; 809: 151134, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-34695460

RESUMO

To effectively reduce the compound pollution of fine particulate matter (PM2.5) and ozone (O3), volatile organic compound (VOC) emission sources are being extensively studied. Studies on VOC emission characteristics have mainly focused on solvent-using and technological sources, while research on the combustion processes of high-energy-consuming industries remains limited. Here, we investigate the emission characteristics of 102 VOC species emitted from eight sources (sintering, pelletizing, steel smelting, a coke oven chimney, the topside of a coke oven, thermal power, and two types of cement kilns) used in four types of high-energy-consuming industries. Our results show significant differences among these sources. The average VOC mass concentrations varied from 0.14 to 7.08 mg/m3. Alkanes had the highest percentage contribution to VOCs from sintering (45.9%) and thermal power (44.6%), while aromatics had the highest percentage contribution from steel smelting (47.8%) and the topside of the coke oven (52.9%). Alkenes were abundant in the coke oven chimney (49.1%), and oxygenated VOCs accounted for 65.3% of the total VOCs from pelletizing. We also observed notable differences between the two types of cement kilns. In general, ethane, ethene, benzene, propane, acetaldehyde, and chloromethane were the dominant VOC species in all sources. The differences between the sources were due to factors such as the applied raw materials, calcination temperature, and end-of-pipe treatment. By reviewing studies from the past 20 years, we found that differences in the number of VOC species and the implementation of ultra-low emissions affect VOC emission characteristics. The coke oven chimney and cement kiln chimney-1 had the highest ozone formation potential and secondary organic aerosol potential, respectively. The VOC emissions from coking, iron and steel, thermal power, and cement industries were 1162.1, 289.9, 311.0, and 470.2 Gg, respectively. Our results highlight the need for more effective control measures to minimize VOC emissions from high-energy-consuming industries.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Ozônio/análise , Compostos Orgânicos Voláteis/análise
7.
Zhonghua Xin Xue Guan Bing Za Zhi ; 38(11): 1038-44, 2010 Nov.
Artigo em Zh | MEDLINE | ID: mdl-21215235

RESUMO

OBJECTIVE: To assess the dose-response relationship between alcohol consumption and relative risk of coronary heart disease (CHD) morbidity, mortality and all-cause mortality among Eastern Asian men. METHODS: Potential prospective cohort studies were retrieved by searching Pubmed (1966 - 2000), Biosis Previews (1980 - 2009), Embase (1980 - 2009) and ISI Web of Knowledge (1986 - 2009) using Medical Subject Headings alcohol drinking, ethanol, coronary heart (or artery) disease, myocardial infarction, mortality, etc; and Koreans, or Japanese or Chinese. From the 28 relevant retrieved reports, 15 prospective cohort studies met the criteria were included. Information on study design, participant characteristics, level of alcohol consumption, CHD outcome, control for potential confounding factors, and risk estimates were abstracted using a standardized protocol. For each study, relative risks (RR) and 95% confidence intervals (CI) were extracted and pooled with either a fixed effect model or random effect model according to the result of the test of heterogeneity. RESULTS: Due to the limited available data for women, this study only comprised of 2406 cases of CHD among 177 723 male subjects. Findings were also pooled from 216 233 male subjects and 15 462 deaths from any cause. Compared with nondrinkers, the RRs on CHD morbidity for those who drank alcohol ≤ 20, 21 - 40, 41 - 60, > 60 g/d were 0.65 (0.34 - 1.23, P = 0.18), 0.48 (0.26 - 0.87, P = 0.02), 0.46 (0.32 - 0.67, P < 0.01), and 0.48 (0.29 - 0.78, P < 0.01) respectively; the RRs on CHD mortality were 0.98 (0.73 - 1.31, P = 0.87), 0.68 (0.58 - 0.79, P < 0.01), 0.64 (0.43 - 0.96, P = 0.03), 0.75 (0.54 - 1.03, P = 0.08); and on all-cause mortality were 0.83 (0.79 - 0.91, P < 0.01), 0.93 (0.87 - 0.99, P = 0.03), 1.01 (0.95 - 1.07, P = 0.86), 1.32 (1.29 - 1.36, P < 0.01). CONCLUSION: Light-to-moderate alcohol intake was associated with decreased risk of CHD morbidity and mortality, while heavy alcohol intake was associated with increased all-cause mortality among Eastern Asian men.


Assuntos
Consumo de Bebidas Alcoólicas , Doença das Coronárias/etiologia , Adulto , Idoso , Consumo de Bebidas Alcoólicas/mortalidade , China/epidemiologia , Doença das Coronárias/mortalidade , Ásia Oriental/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Estudos Prospectivos , República da Coreia/epidemiologia , Fatores de Risco
8.
Zhonghua Xin Xue Guan Bing Za Zhi ; 38(10): 909-13, 2010 Oct.
Artigo em Zh | MEDLINE | ID: mdl-21176635

RESUMO

OBJECTIVE: To assess the diagnostic accuracy of 64-slice computed tomography coronary angiography (64-SCTCA) in individuals with suspected coronary artery disease (CAD). METHODS: The study enrolled 285 individuals undergoing 64-SCTCA with calcium scoring and thereafter invasive coronary angiography (CAG) within 4 weeks for suspected CAD. Pretest probability of having obstructive CAD was determined using the Duke clinical score, which was estimated by type of chest discomfort, age, gender, and traditional risk factors and stratified into 3 levels of probability: low (≤ 30%, n = 80), intermediate (31% to 70%, n = 92), and high (≥ 71%, n = 113). CAD was defined as the presence of at least one vessel of ≥ 50% coronary stenosis on CAG. RESULTS: The patient-based diagnostic accuracy of 64-SCTCA for detecting CAD according to CAG revealed a sensitivity of 81.2%, a specificity of 93.3%, a positive predictive value of 68.0% and negative predictive value of 96.6%. The CAD prevalence in the low, intermediate and high risk groups according to Duke probability was 46.3%, 72.8% and 82.3%, respectively. The sensitivity and positive predictive value were lower in the low probability group than those in the intermediate and high probability groups. For those with coronary artery Agatston calcium score > 400, the diagnostic accuracy was linked with a higher sensitivity but lower specificity. The diagnostic value of 64-SCTCA for proximal and mid-segment of coronary artery was superior to that for distal segment. CONCLUSIONS: 64-SCTCA is mainly indicated in individuals with an intermediate probability of having CAD. The diagnostic value of 64-SCTCA could be affected by coronary artery calcium, lesion location and vessel diameter.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade
9.
ACS Appl Mater Interfaces ; 10(1): 427-436, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29210564

RESUMO

Plasmonic gratings facilitate a robust in situ diagnostic platform for photothermal combustion of nanoenergetic composite thin films using an optical microscope and a high-speed camera. Aluminum nanoparticles (Al NPs) embedded in a fluoropolymer oxidizer are cast onto a plasmonic grating microchip and ignited using a low-power laser. The plasmonic grating enhances both spatial resolution and sufficient photothermal coupling to combust small Al NP clusters, initiating localized flames as small as 600 nm in size. Two-color pyrometry obtained from a high-speed color camera indicates an average flame temperature of 3900 K. Scattering measurements using polarized light microscopy enabled precise identification of individual Al NPs over a large field of view, leading to 3D reconstruction of combustion events.

10.
Sci Rep ; 6: 25234, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-27121605

RESUMO

We report metal/p-Si contact barrier modification through the introduction of either "isolated" or "nonisolated" tilted-target-sputtered sub-2 nm platinum nanoparticles (Pt NPs) in combination with either a 0.98 nm Atomic Layer Deposited Al2O3 or a 1.6 nm chemically grown SiO2 dielectric layer, or both. Here, we study the role of these Pt NP's size dependent properties, i.e., the Pt NP-metal surface dipole, the Coulomb blockade and quantum confinement effect in determining the degree of Fermi level depinning observed at the studied metal/p-Si interfaces. By varying only the embedded Pt NP size and its areal density, the nature of the contact can also be modulated to be either Schottky or Ohmic upon utilizing the same gate metal. 0.74 nm Pt NPs with an areal density of 1.1 × 10(13) cm(-2) show ~382 times higher current densities compared to the control sample embedded with similarly sized Pt NPs with ~1.6 times lower areal densities. We further demonstrate that both Schottky (Ti/p-Si) and poor Ohmic (Au/p-Si) contact can be modulated into a good Ohmic contact with current density of 18.7 ± 0.6 A/cm(2) and 10.4 ± 0.4 A/cm(2), respectively, showing ~18 and ~30 times improvement. A perfect forward/reverse current ratio of 1.041 is achieved for these low doped p-Si samples.

12.
Int J Nanomedicine ; 7: 4649-60, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22942646

RESUMO

BACKGROUND: The purpose of this study was to investigate the downregulation of mRNA expression of vascular endothelial growth factor (VEGF) by triamcinolone acetonide acetate (TAA)-loaded chitosan nanoparticles in human retinal pigment epithelial cells. METHODS: TAA-loaded deoxycholic acid-modified chitosan (TAA/DA-Chit) nanoparticles were prepared via a self-assembly mechanism, and their morphology and zeta potential were examined by transmission electron microscopy and zeta potential analysis, respectively. DA-Chit and TAA/DA-Chit nanoparticle toxicity was evaluated using a Cell Counting Kit-8 assay. The efficiency of cellular uptake was determined using fluorescein isothiocyanate-labeled DA-Chit nanoparticles, in place of TAA/DA-Chit nanoparticles, assessed by both inverted fluorescence microscopy and flow cytometry. Downregulation of VEGF mRNA expression by TAA/DA-Chit nanoparticles was further investigated by real-time reverse transcription polymerase chain reaction (RT-PCR) assay of the treated human retinal pigment epithelial cells. RESULTS: TAA/DA-Chit nanoparticles were prepared with a TAA-loading capacity in the range of 12%-82%, which increased the water solubility of TAA from 0.3 mg/mL to 2.1 mg/mL. These nanoparticles showed oblate shapes 100-550 nm in size in transmission electron microscopic images and had positive zeta potentials. The Cell Counting Kit-8 assay indicated that the DA-Chit and TAA/DA-Chit nanoparticles had no toxicity and low toxicity, respectively, to human retinal pigment epithelial cells. Fluorescein isothiocyanate-labeled DA-Chit nanoparticle uptake by human retinal pigment epithelial cells was confirmed by inverted fluorescence microscopy and flow cytometry. Real-time RT-PCR assay showed that the VEGF mRNA level decreased after incubation of human retinal pigment epithelial cells with TAA/DA-Chit nanoparticles. CONCLUSION: TAA/DA-Chit nanoparticles had a downregulating effect on VEGF mRNA expression in human retinal pigment epithelial cells and low cytotoxicity, which might be beneficial characteristics for the development of future treatment for diabetic retinopathy.


Assuntos
Quitosana/química , Nanopartículas/química , RNA Mensageiro/biossíntese , Epitélio Pigmentado da Retina/efeitos dos fármacos , Triancinolona Acetonida/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Acetatos/farmacologia , Linhagem Celular , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quitosana/farmacologia , Ácido Desoxicólico/química , Ácido Desoxicólico/farmacologia , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Humanos , Nanopartículas/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/fisiologia , Solubilidade , Triancinolona Acetonida/química , Triancinolona Acetonida/farmacocinética , Fator A de Crescimento do Endotélio Vascular/biossíntese
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