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2.
IEEE Trans Image Process ; 32: 6075-6089, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37922167

RESUMEN

In recent years, there has been a growing interest in combining learnable modules with numerical optimization to solve low-level vision tasks. However, most existing approaches focus on designing specialized schemes to generate image/feature propagation. There is a lack of unified consideration to construct propagative modules, provide theoretical analysis tools, and design effective learning mechanisms. To mitigate the above issues, this paper proposes a unified optimization-inspired learning framework to aggregate Generative, Discriminative, and Corrective (GDC for short) principles with strong generalization for diverse optimization models. Specifically, by introducing a general energy minimization model and formulating its descent direction from different viewpoints (i.e., in a generative manner, based on the discriminative metric and with optimality-based correction), we construct three propagative modules to effectively solve the optimization models with flexible combinations. We design two control mechanisms that provide the non-trivial theoretical guarantees for both fully- and partially-defined optimization formulations. Under the support of theoretical guarantees, we can introduce diverse architecture augmentation strategies such as normalization and search to ensure stable propagation with convergence and seamlessly integrate the suitable modules into the propagation respectively. Extensive experiments across varied low-level vision tasks validate the efficacy and adaptability of GDC.

3.
IEEE Trans Pattern Anal Mach Intell ; 45(1): 38-57, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34982677

RESUMEN

In recent years, a variety of gradient-based methods have been developed to solve Bi-Level Optimization (BLO) problems in machine learning and computer vision areas. However, the theoretical correctness and practical effectiveness of these existing approaches always rely on some restrictive conditions (e.g., Lower-Level Singleton, LLS), which could hardly be satisfied in real-world applications. Moreover, previous literature only proves theoretical results based on their specific iteration strategies, thus lack a general recipe to uniformly analyze the convergence behaviors of different gradient-based BLOs. In this work, we formulate BLOs from an optimistic bi-level viewpoint and establish a new gradient-based algorithmic framework, named Bi-level Descent Aggregation (BDA), to partially address the above issues. Specifically, BDA provides a modularized structure to hierarchically aggregate both the upper- and lower-level subproblems to generate our bi-level iterative dynamics. Theoretically, we establish a general convergence analysis template and derive a new proof recipe to investigate the essential theoretical properties of gradient-based BLO methods. Furthermore, this work systematically explores the convergence behavior of BDA in different optimization scenarios, i.e., considering various solution qualities (i.e., global/local/stationary solution) returned from solving approximation subproblems. Extensive experiments justify our theoretical results and demonstrate the superiority of the proposed algorithm for hyper-parameter optimization and meta-learning tasks. Source code is available at https://github.com/vis-opt-group/BDA.

4.
IEEE Trans Image Process ; 31: 239-250, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34847030

RESUMEN

Video deraining is an important issue for outdoor vision systems and has been investigated extensively. However, designing optimal architectures by the aggregating model formation and data distribution is a challenging task for video deraining. In this paper, we develop a model-guided triple-level optimization framework to deduce network architecture with cooperating optimization and auto-searching mechanism, named Triple-level Model Inferred Cooperating Searching (TMICS), for dealing with various video rain circumstances. In particular, to mitigate the problem that existing methods cannot cover various rain streaks distribution, we first design a hyper-parameter optimization model about task variable and hyper-parameter. Based on the proposed optimization model, we design a collaborative structure for video deraining. This structure includes Dominant Network Architecture (DNA) and Companionate Network Architecture (CNA) that is cooperated by introducing an Attention-based Averaging Scheme (AAS). To better explore inter-frame information from videos, we introduce a macroscopic structure searching scheme that searches from Optical Flow Module (OFM) and Temporal Grouping Module (TGM) to help restore latent frame. In addition, we apply the differentiable neural architecture searching from a compact candidate set of task-specific operations to discover desirable rain streaks removal architectures automatically. Extensive experiments on various datasets demonstrate that our model shows significant improvements in fidelity and temporal consistency over the state-of-the-art works. Source code is available at https://github.com/vis-opt-group/TMICS.

5.
IEEE Trans Image Process ; 30: 8278-8292, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34559653

RESUMEN

Alternating Direction Method of Multiplier (ADMM) has been a popular algorithmic framework for separable optimization problems with linear constraints. For numerical ADMM fail to exploit the particular structure of the problem at hand nor the input data information, leveraging task-specific modules (e.g., neural networks and other data-driven architectures) to extend ADMM is a significant but challenging task. This work focuses on designing a flexible algorithmic framework to incorporate various task-specific modules (with no additional constraints) to improve the performance of ADMM in real-world applications. Specifically, we propose Guidance from Optimality (GO), a new customization strategy, to embed task-specific modules into ADMM (GO-ADMM). By introducing an optimality-based criterion to guide the propagation, GO-ADMM establishes an updating scheme agnostic to the choice of additional modules. The existing task-specific methods just plug their task-specific modules into the numerical iterations in a straightforward manner. Even with some restrictive constraints on the plug-in modules, they can only obtain some relatively weaker convergence properties for the resulted ADMM iterations. Fortunately, without any restrictions on the embedded modules, we prove the convergence of GO-ADMM regarding objective values and constraint violations, and derive the worst-case convergence rate measured by iteration complexity. Extensive experiments are conducted to verify the theoretical results and demonstrate the efficiency of GO-ADMM.

6.
Exp Ther Med ; 20(6): 153, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33093891

RESUMEN

Intravenous (i.v.) glucocorticoid is recommended for active moderate-to-severe thyroid-associated ophthalmopathy (TAO). However, the details of the treatment schedule are still debatable. The present prospective randomized trial was performed to compare clinical outcomes and serum cytokines between the two regimens. A cohort of 90 patients with active moderate-to-severe TAO was randomized to receive i.v. methyl prednisolone on a weekly protocol or daily scheme. The response rate was evaluated at the 12-week follow-up visit. Serum interleukin (IL)-2, IL-6 and IL-17 levels were measured in 160 patients with TAO, 60 patients with isolated Graves' disease (GD) and 60 normal control (NC) at baseline, as well as patients with active moderate-to-severe TAO at the 12th week after treatment. The daily scheme had a higher response rate than the weekly protocol without a significant difference (77.8 vs. 63.6%, P>0.05). No major adverse events were recorded under either regimen. Overall, minor events were more common on the daily scheme (11.36 vs. 4.35%, P<0.05)than on the weekly protocol, whereas the deterioration of eye symptoms (two patients) was only reported on the weekly protocol. At baseline, the IL-17 level in the TAO group was higher than that in the isolated GD and NC groups (P<0.05). In addition, the IL-17 level in the active TAO group was higher than that in the inactive TAO group (P<0.05). Furthermore, the IL-17 level had significantly decreased under the two regimens at the 12-week visit (P<0.05). In conclusion, for patients with active moderate-to-severe TAO, daily i.v. glucocorticoid therapy has a relative higher response rate than the weekly protocol with a few more minor adverse events. These two regimens have their own merits with regard to adverse effects. IL-17 has the potential to be a biomarker for evaluating TAO activity and treatment effects.

7.
Zhongguo Zhong Yao Za Zhi ; 44(22): 4888-4895, 2019 Nov.
Artículo en Chino | MEDLINE | ID: mdl-31872597

RESUMEN

A method for determination of 9 isoflavones in Puerariae Lobatae Radix was established and the accuracy and feasibility of the method were verified. The relative correction factors of eight isoflavonoids,3'-hydroxy puerarin,puerarinapioside,3'-methoxy puerarin,puerarin 6″-O-xyloside,daidzin,genistin,formononetin and daidzein were determined by HPLC method with puerarin as the internal standard. The contents of 9 isoflavonoids in 11 batches of samples were determined by external standard method and QAMS.The accuracy and feasibility of the methods were evaluated by comparison of the quantitative results between external standard method and QAMS. The reproducibility of the relative correction factors was good under different experimental conditions,and there was no significant difference between the external standard method of the 9 compounds and the content of QAMS method. The results showed that using puerarin as an internal standard to simultaneously determine the 8 isoflavonoids mentioned above is accurate and feasible. Thus,it can be used as quality control of Puerariae Lobatae Radix.


Asunto(s)
Medicamentos Herbarios Chinos , Isoflavonas , Pueraria , Cromatografía Líquida de Alta Presión , Raíces de Plantas , Reproducibilidad de los Resultados
8.
Zhongguo Zhong Yao Za Zhi ; 44(18): 3948-3953, 2019 Sep.
Artículo en Chino | MEDLINE | ID: mdl-31872729

RESUMEN

In order to confirm the tradition that bolting Saposhnikoviae Radix could not be used as medicine,the content of four chromone components in the cortex and wood of Saposhnikoviae Radix was analyzed by high performance liquid chromatography( HPLC),and the chemical fingerprints were established,12 common peaks were calibrated. The similarity analysis found that the similarity between batches was 0. 115-0. 995,it indicates that the cortex and wood of Saposhnikoviae Radix have certain differences. On this basis,systematic clustering analysis,principal component analysis and orthogonal partial least squares discriminant analysis were carried out with the content of four chromone components and whether they met the pharmacopoeia criteria as the original variables. The results showed that the content of the four components in the cortex of Saposhnikoviae Radix was much higher than that in the wood,and the four components detected were able to distinguish the cortex and the wood of Saposhnikoviae Radix. The results of the study reveal the tradition that bolting Saposhnikoviae Radix should not be used as medicine dut to decreased quality.


Asunto(s)
Apiaceae/química , Medicamentos Herbarios Chinos/química , Cetonas/análisis , Raíces de Plantas/química , Madera/química , Cromatografía Líquida de Alta Presión
9.
J Diabetes ; 11(12): 949-957, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30973204

RESUMEN

BACKGROUND: In this study, we compared the effect on diabetic retinopathy (DR) between oral antidiabetic drugs (OADs) alone and in combination with basal insulin-supported OADs therapy (BOT). [Correction added on 11 November 2019, after first online publication: In Abstract under Background section, "DR" has been corrected into "diabetic retinopathy (DR)".] METHODS: Between January 2015 and January 2018, this study enrolled 290 patients (age 18-65 years) with diabetes duration between 0 and 5 years. Patients were randomly assigned to receive OADs or BOT after 14 days intensive insulin treatment. Examinations were performed at the beginning and end of the study. RESULTS: Fewer patients developed DR in the BOT than OADs group (8 [6.06%] vs 12 [8.3%], respectively), and all cases of DR were non-proliferative. Blood glucose concentrations were higher in the BOT than OADs group at the 3rd month, but lower in the former at the 6th and 12th month. The rate of reaching target HbA1c ≤7% was lower in the BOT than OADs group at the 3rd month (63.6% vs 72.2%, respectively), similar between the two groups at the 6th month (60.6% vs 66.6%, respectively) and higher in the BOT group at the 12th month (75.0% vs 61.1%, respectively). The SD of fasting blood glucose (FBG), coefficient of variation of FBG, SD of blood glucose (SDBG), and mean amplitude of glycemic excursions were lower in the BOT than OADs group. Changes in the levels of three cytokines (interleukin [IL]-1ß, IL-6, and IL-17α) were significantly less in the BOT than OADs group. CONCLUSIONS: Twelve months of BOT decreased the incidence of DR in short-duration type 2 diabetes by reducing glycemia more effectively, stably, and completely than OADs alone.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Retinopatía Diabética/prevención & control , Hipoglucemiantes/administración & dosificación , Insulina Glargina/administración & dosificación , Administración Oral , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Glucemia/efectos de los fármacos , Glucemia/metabolismo , China/epidemiología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/epidemiología , Quimioterapia Combinada , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/efectos adversos , Incidencia , Inyecciones , Insulina Glargina/efectos adversos , Interleucinas/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
10.
Diabetes Ther ; 9(3): 963-971, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29564716

RESUMEN

INTRODUCTION: Basal insulin is widely recommended for the treatment of type 2 diabetes mellitus (T2DM) patients who are unable to achieve glycemic control with oral antidiabetic drug(s) (OADs). However, some patients are still unable to control their blood glucose levels even when on basal insulin-supported OAD(s) therapy (BOT). The aim of this study was to investigate the factor(s) predicting patient response to BOT. METHODS: A total of 212 patients with T2DM, ranging in age from 18 to 65 years, admitted to the university hospital of Sun Yat-sen University, Guangzhou, China, were enrolled in the study between January 2013 and July 2016. All patients had fasting blood glucose levels of ≥ 10.0 mmol/L despite receiving OAD(s) treatment. According to study design, these patients first received intensive insulin therapy for 2 weeks to attain and maintain their glycemic goals and then were switched to BOT. Responders were defined as subjects who maintained their glycemic targets with BOT for at least 3 months; all others were considered to be non-responders. The characteristics between responders and non-responders were compared. RESULTS: Compared with non-responders, responders had a shorter duration of diabetes (5.1 ± 5.0 vs. and 10.1 ± 3.2 years; P  < 0.001) and a higher 2-h postprandial C-peptide-to-fasting C-peptide ratio (2 h-PCP/FCP: 1.95 ± 0.51 vs. 1.67 ± 0.32; P  < 0.01). Responders showed a lower proportion of previous treatment with insulin (69/100 vs 40/3; P  < 0.001) and sulfonlureas or glinides (116/50 vs 40/0; P <0.001) than non-responders. Multivariate logistic regression analysis showed that previous insulin treatment (odds ratio [OR] 17.677, 95% confidence interval [CI] 5.205-60.027; P  < 0.001) and the 2 h-PCP/FCP ratio (OR 0.241, 95% CI 0.058-0.679; P  = 0.007) had predictive value. CONCLUSIONS: A higher 2 h-PCP/FCP ratio and a lack of previous insulin treatment increase the likelihood of BOT success.

11.
J Am Heart Assoc ; 6(8)2017 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-28751541

RESUMEN

BACKGROUND: Percutaneous coronary intervention has been widely used in the treatment of ischemic heart disease, but vascular restenosis is a main limitation of percutaneous coronary intervention. Our previous work reported that caveolin-1 had a key functional role in intimal hyperplasia, whereas whether Cavin-1 (another important caveolae-related protein) was involved is still unknown. Therefore, we will investigate the effect of Cavin-1 on neointimal formation. METHODS AND RESULTS: Balloon injury markedly reduced Cavin-1 protein and enhanced ubiquitin protein expression accompanied with neointimal hyperplasia in injured carotid arteries, whereas Cavin-1 mRNA had no change. In cultured vascular smooth muscle cells (VSMCs), Cavin-1 was downregulated after inhibition of protein synthesis by cycloheximide, which was distinctly prevented by pretreatment with proteasome inhibitor MG132 but not by lysosomal inhibitor chloroquine, suggesting that proteasomal degradation resulted in Cavin-1 downregulation. Knockdown of Cavin-1 by local injection of Cavin-1 short hairpin RNA (shRNA) into balloon-injured carotid arteries in vivo promoted neointimal formation. In addition, inhibition or overexpression of Cavin-1 in cultured VSMCs in vitro prompted or suppressed VSMC proliferation and migration via increasing or decreasing extracellular signal-regulated kinase phosphorylation and matrix-degrading metalloproteinases-9 activity, respectively. However, under basic conditions, the effect of Cavin-1 on VSMC migration was stronger than on proliferation. Moreover, our results indicated that Cavin-1 regulated caveolin-1 expression via lysosomal degradation pathway. CONCLUSIONS: Our study revealed the role and the mechanisms of Cavin-1 downregulation in neointimal formation by promoting VSMC proliferation, migration, and synchronously enhancing caveolin-1 lysosomal degradation. Cavin-1 may be a potential therapeutic target for the treatment of postinjury vascular remodeling.


Asunto(s)
Angioplastia de Balón/efectos adversos , Traumatismos de las Arterias Carótidas/metabolismo , Caveolina 1/metabolismo , Movimiento Celular , Proliferación Celular , Proteínas de la Membrana/metabolismo , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Neointima , Proteínas de Unión al ARN/metabolismo , Animales , Traumatismos de las Arterias Carótidas/etiología , Traumatismos de las Arterias Carótidas/genética , Traumatismos de las Arterias Carótidas/patología , Arteria Carótida Externa/metabolismo , Arteria Carótida Externa/patología , Células Cultivadas , Modelos Animales de Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Lisosomas/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Proteínas de la Membrana/genética , Músculo Liso Vascular/lesiones , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/patología , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Interferencia de ARN , ARN Interferente Pequeño/administración & dosificación , Proteínas de Unión al ARN/genética , Ratas Sprague-Dawley , Transducción de Señal , Factores de Tiempo , Transfección , Remodelación Vascular
12.
ACS Appl Mater Interfaces ; 9(24): 20779-20786, 2017 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-28570044

RESUMEN

Porous carbon nanotubes (PCNTs) have attracted considerable attention due to their large specific surface areas and unique one-dimensional (1D) structures. However, most of the reported synthetic strategies for PCNTs are complex and expensive. Herein, we present a self-templated, surfactant-free strategy for the synthesis of high-quality PCNTs with high surface area by direct carbonization of 1D hyper-cross-linked polymer nanotubes. The precursors of the 1D hyper-cross-linked polymer nanotubes were synthesized by FeCl3 catalyzed Friedel-Crafts alkylation of aromatic hydrocarbons with formaldehyde dimethyl acetal. It was found that the monomer concentration and mechanical agitation play crucial roles in the formation of the 1D tubular hyper-cross-linked polymer precursor. The tube size of the resulting PCNTs could be finely controlled by the aromatic monomers with different molecular sizes. The excellent electrochemical performances of the supercapacitors fabricated from the PCNTs demonstrate that these PCNTs are promising for the electrode materials of high-performance supercapacitors. This work highlights that the facile synthetic strategy for PCNTs would open up new avenues of porous carbon nanotube materials with promising applications.

13.
Obes Res Clin Pract ; 10(6): 633-641, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27004692

RESUMEN

BACKGROUND: Oestrogen has anti-inflammatory property in obesity. However, the mechanism is still not defined. OBJECTIVE: To investigate the effect of oestrogen on LPS-induced monocyte chemoattractant protein-1 (MCP-1) production in adipocytes. METHODS: Lipopolysaccharides (LPS) was used to imitate inflammatory responses and monocyte chemotactic protein-1 (MCP-1) was selected as an inflammatory marker to observe. 17ß-Estradiol (E2), SB203580 (SB), pyrrolidine dithiocarbamate (PDTC), pertussis toxin (PTX), wortmannin (WM), p65 siRNA and p38 MAPK siRNA were pre-treated respectively or together in LPS-induced MCP-1. Then p38 MAPK and NF-κB cascade were silenced successively to observe the change of each other. Lastly, oestrogen receptor (ER) α agonist, ERß agonist and ER antagonist were utilised. RESULTS: LPS-induced MCP-1 largely impaired by pre-treatment with E2, SB, PDTC or silencing NF-κB subunit. E2 inhibited LPS-induced MCP-1 in a time- and dose-dependent manner, which was related to the suppression of p65 translocation to nucleus. Furthermore, LPS rapidly activated p38 MAPK, while E2 markedly inhibited this activation. It markedly attenuated LPS-stimulated p65 translocation to nucleus and MCP-1 production by transfecting with p38 MAPK siRNA or using p38 MAPK inhibitor. The oestrogen's inhibitory effect was mimicked by the ERα agonist, but not by the ERß agonist. The inhibition of E2 on p38 MAPK phosphorylation was prevented by ER antagonist. CONCLUSIONS: E2 inhibits LPS-stimulated MCP-1 in adipocytes. This effect is related to the inhibition of p38 MAPK/NF-κB cascade, and ERα appears to be the dominant ER subtype in these events.


Asunto(s)
Adipocitos/metabolismo , Quimiocina CCL2/metabolismo , Estradiol/metabolismo , Receptor alfa de Estrógeno/metabolismo , Inflamación/metabolismo , FN-kappa B/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Adipocitos/efectos de los fármacos , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Animales , Transporte Biológico , Núcleo Celular , Células Cultivadas , Estradiol/farmacología , Antagonistas del Receptor de Estrógeno/farmacología , Estrógenos/metabolismo , Estrógenos/farmacología , Femenino , Inflamación/inducido químicamente , Inflamación/etiología , Lipopolisacáridos , Obesidad/complicaciones , Obesidad/metabolismo , Fosforilación , Pirrolidinas/metabolismo , ARN Interferente Pequeño/metabolismo , Ratas Sprague-Dawley , Tiocarbamatos/metabolismo , Factor de Transcripción ReIA/metabolismo
14.
Diabetes Res Clin Pract ; 108(3): e67-70, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25841300
15.
Zhonghua Yi Xue Za Zhi ; 93(36): 2861-6, 2013 Sep 24.
Artículo en Chino | MEDLINE | ID: mdl-24373396

RESUMEN

OBJECTIVE: To compare the morphological and functional differences of human primary preadipocytes from different fat depots and explore the effects of insulin glargine on their proliferation and differentiation. METHODS: Primary preadipocytes isolated from human subcutaneous and omental adipose tissue by collagenase I were passaged in vitro.Inverted phase contrast microscope was used to observe the morphological differences of two kinds of preadipocytes. Then two kinds of preadipocytes were cultured or induced to differentiation with different doses of insulin glargine. The methyl thiazolyl tetrazolium (MTT) assay was used to detect their proliferative differences.Reverse transcription-polymerase chain reaction (RT-PCR) was used to observe the effects of insulin on adipogenic gene expression. RESULTS: (1) Both preadipocytes could be successfully cultured from adipose tissue and amplified in vitro.Subcutaneous preadipocytes were more slender and proliferated more quickly while omental preadipocytes were polygonal and aged easily.(2) MTT results showed that insulin glargine could inhibit the proliferation of omental preadipocytes in a dose-dependent fashion. After 72 h incubation, compared with negative control, the absorbance (A) value of 1000 nmol/L insulin glargine group decreased greatly (0.144 ± 0.021 vs 0.267 ± 0.040, P < 0.01). But it had no effect on subcutaneous preadipocytes (0.305 ± 0.045 vs 0.350 ± 0.037, P > 0.05). (3) Insulin at 500 nmol/L was a suitable concentration for inducing differentiation.RT-PCR analysis showed that, for subcutaneous adipocytes, adipogenic genes such as peroxisome proliferator-activated receptor gamma (PPARγ) (F = 31.31, P < 0.01) and CCAAT enhancer binding protein α (C/EBPα) (F = 9.86, P < 0.05) had the highest mRNA expression while preadipocytes gene Pref-1 had the lowest expression at this concentration. But insulin dose had no obvious effect on PPARγ or C/EBPα mRNA (P > 0.05) for omental adipocytes. CONCLUSION: Insulin glargine could inhibit the proliferation of omental preadipocytes, and enhance the differentiation of subcutaneous and omental preadipocytes.


Asunto(s)
Adipocitos/citología , Tejido Adiposo/citología , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Insulina de Acción Prolongada/farmacología , Adipocitos/efectos de los fármacos , Células Cultivadas , Humanos , Insulina Glargina , Epiplón/citología , Grasa Subcutánea/citología
16.
J Nutr Biochem ; 23(12): 1716-24, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22569348

RESUMEN

Insulin resistance is recognized as a common metabolic factor which predicts the future development of both type 2 diabetes and atherosclerotic disease. Resveratrol (RSV), an agonist of estrogen receptor (ER), is known to affect insulin sensitivity, but the mechanism is unclear. Evidence suggests that caveolin-3 (CAV-3), a member of the caveolin family, is involved in insulin-stimulated glucose uptake. Our recent work indicated that estrogen via ER improves glucose uptake by up-regulation of CAV-3 expression. Here, we investigated the role of CAV-3 in the effect of RSV on insulin resistance in skeletal muscle both in vivo and in vitro. The results demonstrated that RSV ameliorated high-fat-diet (HFD)-induced glucose intolerance and insulin resistance in ovariectomized rats. RSV elevated insulin-stimulated glucose uptake in isolated soleus muscle in vivo and in C2C12 myotubes in vitro by enhancing GLUT4 translocation to the plasma membrane rather than increasing GLUT4 protein expression. Through ERα-mediated transcription, RSV increased CAV-3 protein expression, which contributed to GLUT4 translocation. Moreover, after knockdown of CAV-3 gene, the effects of RSV on glucose uptake and the translocation of GLUT4 to the plasma membrane, as well as the association of CAV-3 and GLUT4 in the membrane, were significantly attenuated. Our findings demonstrated that RSV via ERα elevated CAV-3 expression and then enhanced GLUT4 translocation to the plasma membrane to promote glucose uptake in skeletal muscle, exerting its protective effects against HFD-induced insulin resistance. It suggests that this pathway could represent an effective therapeutic target to fight against insulin resistance syndrome induced by HFD.


Asunto(s)
Caveolina 3/metabolismo , Dieta Alta en Grasa/efectos adversos , Transportador de Glucosa de Tipo 4/metabolismo , Resistencia a la Insulina , Músculo Esquelético/metabolismo , Estilbenos/farmacología , Animales , Caveolina 3/genética , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Receptor alfa de Estrógeno/metabolismo , Femenino , Glucosa/metabolismo , Glucosa/farmacocinética , Intolerancia a la Glucosa/prevención & control , Insulina/farmacología , Fibras Musculares Esqueléticas/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Ovariectomía , Sustancias Protectoras/farmacología , Transporte de Proteínas/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Resveratrol
17.
Food Chem ; 133(2): 430-6, 2012 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25683416

RESUMEN

A simple, rapid and improved method was developed to isolate high-purity baicalein and wogonin from Scutellariae radix. The method involves endogenous baicalinase-catalysed hydrolysis (EBCH), partition, automated low-pressure preparative chromatography (LPPC) and recrystallisation without multiple and tedious column chromatography. This process was optimised for large scale production of baicalein and wogonin with high yields, low costs and process automation. The transformation ratio of baicalin and wogonoside reached 98.21% and 96.60% after EBCH, leading to an increase of 5.41-fold in baicalein and 3.89-fold in wogonin, compared to a raw sample without hydrolysis. The purity of final products was more than 98% after one-step LPPC and recrystallisation. The experimental results show that EBCH-LPPC is an effective method for preparing high purity antioxidants.


Asunto(s)
Flavanonas/aislamiento & purificación , Scutellaria baicalensis/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Medicamentos Herbarios Chinos/química , Flavanonas/química
18.
Food Chem ; 133(2): 437-44, 2012 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25683417

RESUMEN

Solvent-free microwave extraction (SFME) of the essential oil from Dryopteris fragrans and its antioxidant activity were investigated. A central composite design combined with response surface methodology was applied to study the influences of extraction time, irradiation power and humidity (proportion of water pretreatment). A maximal extraction yield of 0.33% was achieved under optimal conditions of extraction time 34 min, irradiation power 520 W and humidity 51%. Sixteen compounds, representing 89.65% of the oil, were identified, of which the major ones, (1R,4S,11R)-4,6,6,11-tetramethyltricyclo[5.4.0.0(4,8)]undecan-1-ol (30.49%), 1R,4S,7S,11R-2,2,4,8-tetramethyltricyclo[5.3.1.0(4,11)]undec-8-ene (22.91%) and, 1,4,4a,5,6,7,8,8a-octahydro-2,5,5,8a-tetramethyl-1-naphthalenemethanol (15.11%), accounted for 68.51% of the oil. The antioxidant activity of the essential oil was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene/linoleic acid, and reducing power assay, the IC50 values were 0.19, 0.09 and 0.18 mg/mL, respectively. All these results suggest that SFME represents an excellent alternative protocol for production of essential oils from plant materials.


Asunto(s)
Dryopteris/química , Microondas , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Aceites Volátiles/química , Aceites Volátiles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Solventes/química
19.
Diabetes Metab Res Rev ; 28(3): 236-40, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21898754

RESUMEN

BACKGROUND: Oral anti-diabetes drugs plus basal insulin (OAD + insulin) therapy in patients with newly diagnosed type 2 diabetes might improve ß-cell function and result in extended glycaemic remission. This randomised trial compared the effect on ß-cell function and diabetes remission rate between oral drug alone or with addition of basal insulin. METHODS: One hundred and twenty-nine patients, aged 35-50 years, were enrolled between June 2005 and June 2009. For initial correction of hyperglycaemia, patients with fasting plasma glucose ≥9.0 mmol/L and HbA(1c) ≥ 9.0%, were randomly assigned to therapy with oral drugs + insulin or oral drugs alone. Treatment was stopped after normoglycaemia was maintained for 3 months. Patients were then followed-up with diet and physical exercise. Blood glucose, HbA(1c) and insulin were measured prior to treatment and at 1-year follow-up. RESULTS: More patients achieved target glycaemic control in the oral drugs + insulin group [98.3% (58 of 59)] in less time [(10.4 ± 2.5) days] than those in the oral drug group [95.7% (67 of 70) and (12.4 ± 3.4) days]. At 1-year follow-up, more patients maintained target glycaemia without any drugs in the oral drug + insulin group than in the oral drug group [37.9% (22 of 58) vs 20.9% (14 of 67)]. Both treatments improved homeostasis model assessment-ß (HOMA-ß) and homeostasis model assessment-insulin resistance (HOMA-IR) significantly. They had similar effects on insulin resistance [lg(HOMA-IR): (0.50 ± 0.09) vs (0.48 ± 0.09), p = 0.23]. However, oral drugs + insulin could recover ß-cell function much more than OAD alone could [lg(HOMA-ß): (2.17 ± 0.14) vs (2.11 ± 0.13), p = 0.03]. CONCLUSION: In newly diagnosed type 2 diabetes, therapy with oral drugs + insulin has had favourable outcomes on recovery and maintenance of ß-cell function and protracted glycaemic remission compared with treatment with oral drugs alone.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Células Secretoras de Insulina/efectos de los fármacos , Insulina/administración & dosificación , Administración Oral , Adulto , Femenino , Homeostasis , Humanos , Resistencia a la Insulina/fisiología , Masculino , Metformina/administración & dosificación , Persona de Mediana Edad , Modelos Biológicos , Compuestos de Sulfonilurea/administración & dosificación
20.
Zhonghua Yi Xue Za Zhi ; 90(48): 3395-8, 2010 Dec 28.
Artículo en Chino | MEDLINE | ID: mdl-21223811

RESUMEN

OBJECTIVE: To explore the depot-specific mRNA and protein expression of retinol-binding protein 4 (RBP4) in human subcutaneous and omental adipose tissue and investigate their relationship with the serum RBP4 levels, obesity and insulin resistance. METHODS: A total of 41 subjects with normal glucose regulation were recruited. Among them, there were 29 cases with normal body mass index (BMI) and 12 cases with BMI ≥ 24 kg/m(2). All were prepared to undergone a selective abdominal surgery. The levels of serum RBP4 and fasting insulin (FINS) were measured by ELISA (enzyme-linked immunosorbent assay) and chemiluminescence ELISA kit respectively. Fasting plasma glucose (FPG) was tested by glucose oxidase and the home model insulin resistance index (HOMA-IR) calculated. Real-time PCR (RT-PCR) and Western blot were employed to assess the relative mRNA and protein expression of RBP4 in subcutaneous and omental adipose tissues. The mRNA and protein expression of RBP4 from different fat depots were compared and their correlations with BMI, the serum RBP4 concentrations and HOMA-IR analyzed. RESULTS: (1) The serum concentrations of RBP4, FINS and HOMA-IR were significantly higher in overweight and obesity group than those in the normal BMI group [RBP4: (39.61 ± 1.57) mg/L vs (33.40 ± 1.28) mg/L, P < 0.01; FINS: (8.82 ± 3.79) mU/L vs (6.43 ± 4.38) mU/L, P < 0.05; HOMA-IR: 1.91 ± 0.85 vs 1.36 ± 0.72, P < 0.05]. (2) The expression levels of RBP4 mRNA and protein were significantly higher in omental adipose tissues than those in subcutaneous adipose tissue [mRNA: (5.88 ± 2.37) vs (2.07 ± 1.66), P < 0.01; protein: (0.76 ± 0.18 vs 0.15 ± 0.07, P < 0.05] and these depots difference in both groups (P < 0.05). Moreover, the overweight patients had the higher expression levels of RBP4 mRNA and protein in omental adipose tissue than normal BMI group (mRNA: 7.52 ± 0.58 vs 4.37 ± 0.45, P < 0.01; protein: 0.92 ± 0.23 vs 0.57 ± 0.13, P < 0.05). (3) The expressions of both RBP4 mRNA and protein in the omental adipose tissue were positively correlated with BMI, waist circumstance, serum concentrations of RBP4, FINS and HOMA-IR. The expression of was negatively correlated with HOMA-IR (r = -0.635, P < 0.05) in subcutaneous adipose tissue. No correlations were found between the expressions of RBP4 mRNA and protein in subcutaneous adipose tissue with BMI, waist circumstance, serum RBP4 and FINS concentrations. CONCLUSIONS: There is depot-specific expression of RBP4 in human subcutaneous and omental adipose tissues. A high expression of RBP4 in omental adipose tissue and an elevated level of serum RBP4 may contribute to the pathogenesis of obesity and IR.


Asunto(s)
Obesidad/metabolismo , Epiplón/metabolismo , Proteínas Plasmáticas de Unión al Retinol/metabolismo , Grasa Subcutánea/metabolismo , Adolescente , Adulto , Glucemia/análisis , Estudios de Casos y Controles , Femenino , Humanos , Resistencia a la Insulina , Persona de Mediana Edad , Sobrepeso/metabolismo , Proteínas Plasmáticas de Unión al Retinol/genética , Adulto Joven
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