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1.
Materials (Basel) ; 17(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38793288

RESUMO

Knowledge about the thermodynamic equilibria of the P2O5-Na2O and P2O5-MgO systems is very important for controlling the phosphorus content of steel materials in the process of steelmaking dephosphorization. The phase equilibrium and thermodynamic data of the P2O5-Na2O and P2O5-MgO systems were critically evaluated and re-assessed by the CALPHAD (CAlculation of PHAse Diagram) approach. The liquid phase was described by the ionic two-sublattice model for the first time with the formulas (Na+1)P(O-2, PO3-1, PO4-3, PO5/2)Q and (Mg+2)P(O-2, PO3-1, PO4-3, PO5/2)Q, respectively, and the selection of the species constituting the liquid phase was based on the structure of the phosphate melts. A new and improved self-consistent set of thermodynamic parameters for the P2O5-Na2O and P2O5-MgO systems was finally obtained, and the calculated phase diagram and thermodynamic properties exhibited excellent agreement with the experimental data. The difference in the phase composition of invariant reactions from the experimentally determined values reported in the literature is less than 0.9 mol.%. The present thermodynamic modeling contributes to constructing a multicomponent oxide thermodynamic database in the process of steelmaking dephosphorization.

2.
J Neurosci ; 44(20)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38569924

RESUMO

The superior colliculus (SC) is a prominent and conserved visual center in all vertebrates. In mice, the most superficial lamina of the SC is enriched with neurons that are selective for the moving direction of visual stimuli. Here, we study how these direction selective neurons respond to complex motion patterns known as plaids, using two-photon calcium imaging in awake male and female mice. The plaid pattern consists of two superimposed sinusoidal gratings moving in different directions, giving an apparent pattern direction that lies between the directions of the two component gratings. Most direction selective neurons in the mouse SC respond robustly to the plaids and show a high selectivity for the moving direction of the plaid pattern but not of its components. Pattern motion selectivity is seen in both excitatory and inhibitory SC neurons and is especially prevalent in response to plaids with large cross angles between the two component gratings. However, retinal inputs to the SC are ambiguous in their selectivity to pattern versus component motion. Modeling suggests that pattern motion selectivity in the SC can arise from a nonlinear transformation of converging retinal inputs. In contrast, the prevalence of pattern motion selective neurons is not seen in the primary visual cortex (V1). These results demonstrate an interesting difference between the SC and V1 in motion processing and reveal the SC as an important site for encoding pattern motion.


Assuntos
Camundongos Endogâmicos C57BL , Percepção de Movimento , Estimulação Luminosa , Retina , Colículos Superiores , Vias Visuais , Animais , Colículos Superiores/fisiologia , Percepção de Movimento/fisiologia , Camundongos , Masculino , Feminino , Retina/fisiologia , Estimulação Luminosa/métodos , Vias Visuais/fisiologia , Neurônios/fisiologia , Reconhecimento Visual de Modelos/fisiologia
3.
Anal Bioanal Chem ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441613

RESUMO

The development of novel catalyst with high catalytic activity is important for electrochemical non-enzymatic glucose sensing. Here, iridium single-atom/nickel oxide nanoparticle/N-doped graphene nanosheet (Ir1/NiO/NG) with the loading of 1.13 wt% Ir was successfully synthesized for constructing electrochemical non-enzymatic glucose sensor for the first time. The morphology and structure of Ir1/NiO/NG were characterized by XRD, SEM, TEM, HRTEM, and XPS, and the presence of Ir SAs was confirmed by AC-HAADF-STEM. The Ir1/NiO/NG shows 65 mV lower oxidation potential and 3.3 times higher response current than Ni(OH)2/NG. In addition, Ir1/NiO/NG exhibits high sensitivity (70.09 µA mM-1 cm-2), excellent selectivity, low detection limit (2.00 µM), and great stability (91.53% current remaining after 21 days) for electrochemical non-enzymatic glucose sensing. The outstanding catalytic and sensing performance of Ir1/NiO/NG is mainly attributed to synergistic effect of Ir SAs, NiO nanoparticles, and highly conductive NG, which modulate the electronic and geometric structure of Ir1/NiO/NG. This work shows the promising potential of SACs in electrochemical sensing.

4.
Adv Mater ; 36(12): e2303740, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37392137

RESUMO

Soft robots are composed of compliant materials that facilitate high degrees of freedom, shape-change adaptability, and safer interaction with humans. An attractive choice of material for soft robotics is crosslinked networks of liquid crystal polymers (LCNs), as they are responsive to a wide variety of external stimuli and capable of undergoing fast, programmable, complex shape morphing, which allows for their use in a wide range of soft robotic applications. However, unlike hydrogels, another popular material in soft robotics, LCNs have limited applicability in flooded or aquatic environments. This can be attributed not only to the poor efficiency of common LCN actuation methods underwater but also to the complicated relationship between LCNs and water. In this review, the relationship between water and LCNs is elaborated and the existing body of literature is surveyed where LCNs, both hygroscopic and non-hygroscopic, are utilized in aquatic soft robotic applications. Then the challenges LCNs face in widespread adaptation to aquatic soft robotic applications are discussed and, finally, possible paths forward for their successful use in aquatic environments are envisaged.

5.
PLoS One ; 18(11): e0293306, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37992087

RESUMO

Cash holding is an important strategic decision of enterprises. As a macro-level factor, economic policy uncertainty causes risks, affecting enterprises' cash holdings. Taking the quarterly financial data of China's A-share non-financial listed firms for 2010-2020 as a sample, this study adopts the OLS and fixed effect models to investigate how corporate cash holdings are affected by economic policy uncertainty. The findings indicate that economic policy uncertainty is directly proportional to the level of cash that listed corporations hold. The higher the uncertainty, the more cash the company holds. Among them, state-owned enterprises and the manufacturing industry are more significantly affected by economic policy uncertainty. Finally, considering the regional marketization level and the differences in financing constraints enterprises face, it is concluded through grouping empirical studies that enterprises located in regions with lower marketization levels are more susceptible to policy uncertainty, while financially constrained enterprises are more susceptible to economic policy uncertainty. The study of economic policy uncertainty is helpful to guide enterprises to realize the importance of coping strategies in advance under the background of intensifying economic policy uncertainty. Therefore, this paper proposes to introduce policies on the premise of fully considering the smoothness of the economy and the differences in the conditions of firms of different natures, as well as some proposals to alleviate financing constraints, reduce the adverse effects of uncertainty on firms, and bolster the marketization process.


Assuntos
Adaptação Psicológica , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Incerteza , China , Pesquisa Empírica
6.
Anal Methods ; 15(42): 5564-5576, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37861233

RESUMO

Owing to the versatile photophysical and chemical properties, spherical nucleic acids (SNAs) have been widely used in biosensing. However, traditional SNAs are formed by self-assembly of thiolated DNA on the surface of a gold nanoparticle (AuNP), where it is challenging to precisely control the orientation and surface density of DNA. As a new SNA, a polyadenine (polyA)-mediated SNA using the high binding affinity of consecutive adenines to AuNPs shows controllable surface density and configuration of DNA, which can be used to improve the performance of a biosensor. Herein, we first introduce the properties of polyA-mediated SNAs and fundamental principles regarding the polyA-AuNP interaction. Then, we provide an overview of current representative synthesis methods of polyA-mediated SNAs and their advantages and disadvantages. After that, we summarize the application of polyA-mediated SNAs in biosensing based on fluorescence and colorimetric methods, followed by discussion and an outlook of future challenges in this field.


Assuntos
Nanopartículas Metálicas , Ácidos Nucleicos , Ouro/química , Hibridização de Ácido Nucleico/métodos , Nanopartículas Metálicas/química , DNA/química
7.
Endocrine ; 82(2): 311-318, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37615814

RESUMO

PURPOSE: Haptoglobin (Hp) is a hemoglobin-binding protein that functions as an antioxidant in human plasma. It is reported that glycemic variability (GV) plays a key role in diabetes-related complications associated with impaired glucose metabolism and oxidative stress. Here we aim to investigate whether the effect of GV on diabetic macroangiopathy depends on Hp genotype in type 2 diabetes. METHODS: A number of 860 Chinese patients with type 2 diabetes was genotyped and assigned to two Hp subgroups (Hp 2-2 and Hp 1 carriers). Glycemic variability (GV) was assessed by using a retrospective continuous glucose monitoring system for three consecutive days, and it was measured using the glucose coefficient of variation (%CV), which is calculated as the ratio of glucose standard deviation to glucose mean. Clinical features, history of cardiac surgery, and vascular imaging tests were utilized to diagnose macroangiopathy. We evaluated the interaction between Hp genotypes and %CV on diabetic macroangiopathy. Furthermore, serum concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured using an enzyme-linked immunosorbent assay as a biomarker of oxidative stress. RESULTS: Serum 8-OHdG levels were positively correlated with %CV in Hp 1 carriers (r = 0.117; p = 0.021). Patients in the highest %CV tertile were associated with a higher prevalence of diabetic macroangiopathy than those in the lowest %CV tertile in Hp 1 carriers (OR = 2.461 [95% CI, 1.183-5.121], p = 0.016), but not in those with Hp 2-2 genotype (OR = 0.540 [95% CI, 0.245-1.191], p = 0.127). A significant interactive effect of Hp genotypes and %CV on diabetic macroangiopathy was found (p interaction = 0.008). CONCLUSION: Hp genotype modifies the effect of GV on diabetic macroangiopathy among Chinese patients with type 2 diabetes.


Assuntos
Complicações do Diabetes , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Haptoglobinas/genética , Haptoglobinas/análise , Estudos Transversais , Estudos Retrospectivos , Automonitorização da Glicemia , Glicemia/metabolismo , Hemoglobinas Glicadas , Genótipo
8.
Nat Commun ; 14(1): 1877, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37015926

RESUMO

Despite spectacular progress in microfluidics, small-scale liquid manipulation, with few exceptions, is still driven by external pumps and controlled by large-scale valves, increasing cost and size and limiting complexity. By contrast, optofluidics uses light to power, control and monitor liquid manipulation, potentially allowing for small, self-contained microfluidic devices. Here we demonstrate a soft light-propelled actuator made of liquid crystal gel that pumps microlitre volumes of water. The strip of actuating material serves as both a pump and a channel leading to an extremely simple microfluidic architecture that is both powered and controlled by light. The performance of the pump is well explained by a simple theoretical model in which the light-induced bending of the actuator competes with the liquid's surface tension. The theory highlights that effective pumping requires a threshold light intensity and strip width. The proposed system explores the benefits of shifting the complexity of microfluidic systems from the fabricated device to spatio-temporal control over stimulating light patterns.

9.
Front Bioeng Biotechnol ; 11: 1310017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38268940

RESUMO

Introduction: An ideal bone repair scaffold should have dual functions of osteoinductive ability and in vivo imaging. In this study, the simultaneous substitution of silicon (Si) and gadolinium (Gd) in hydroxyapatite (HA) as potential multifunctional bone graft materials has been successfully developed. Methods: A series of HA nanoparticles (HA NPs) doped with different proportions of Si and Gd were prepared. The chemical structure and phase composition of the materials were analyzed using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The microstructure, magnetic properties, surface potential, and cytotoxicity of the materials were also analyzed. The magnetic resonance imaging (MRI) effect of Gd&Si-HA/poly(lactic-co-glycolic acid) (Gd&Si-HA/PLGA) composite materials was evaluated. Osteogenic-related gene expression, alkaline phosphatase (ALP) level, and mineralization capacity of MC3T3-E1 cultured on Gd&Si-HA/PLGA composite materials were also detected. Results and Discussion: The 1.5Gd&Si-HA@PLGA group showed good ability to promote osteogenic differentiation of cells. The MRI effect of the 1.5Gd&Si-HA@PLGA scaffold was observable. This HA material containing Si and Gd co-doping has a broad application prospect in the field of bone tissue engineering owing to its ability to enhance osteoinductive property and improve MRI effect.

10.
Cardiovasc Diabetol ; 21(1): 265, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36461077

RESUMO

BACKGROUND: Dimethylarginine dimethylaminohydrolase (DDAH) 1 maintains the bioavailability of nitric oxide by degrading asymmetric dimethylarginine (ADMA). Here, we aimed to investigate the effect of haptoglobin (Hp) genotype on the association of ADMA and DDAH 1 polymorphism with diabetic macroangiopathy. METHODS: In stage 1, 90 Chinese participants with type 2 diabetes were enrolled to measure a panel of targeted metabolites, including ADMA, using tandem mass spectrometry (BIOCRATES AbsoluteIDQ™ p180 kit). In stage 2, an independent cohort of 2965 Chinese patients with type 2 diabetes was recruited to analyze the effect of Hp genotype on the association between DDAH 1 rs233109 and diabetic macroangiopathy. Hp genotypes were detected using a validated assay based on the TaqMan method. DDAH 1 rs233109 was genotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy using the MassARRAY platform. RESULTS: In stage 1, serum ADMA levels correlated with common Hp genotypes (ß ± SE = - 0.049 ± 0.023, P = 0.035), but not with diabetic macroangiopathy (P = 0.316). In stage 2, the distribution of DDAH 1 rs233109 genotype frequencies was 15% (CC), 47% (TC), and 38% (TT), which was in Hardy-Weinberg equilibrium (P = 0.948). A significant Hp genotype by rs 233109 genotype interaction effect on diabetic macroangiopathy was found (P = 0.017). After adjusting for confounders, patients homozygous for rs233109 CC were more likely to develop diabetic macroangiopathy than those carrying TT homozygotes in the Hp 2-2 subgroup [odds ratio = 1.750 (95% confidence interval, 1.101-2.783), P = 0.018]. CONCLUSION: Hp genotype affects the association between DDAH 1 rs233109 and diabetic macroangiopathy in Chinese patients with type 2 diabetes.


Assuntos
Amidoidrolases , Complicações do Diabetes , Diabetes Mellitus Tipo 2 , Haptoglobinas , Doenças Vasculares , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/genética , Genótipo , Haptoglobinas/genética , Amidoidrolases/genética
11.
Adv Mater ; : e2209683, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36525600

RESUMO

Light-fueled self-oscillators based on soft actuating materials have triggered novel designs for small-scale robotic constructs that self-sustain their motion at non-equilibrium states and possess bioinspired autonomy and adaptive functions. However, the motions of most self-oscillators are reciprocal, which hinders their use in sophisticated biomimetic functions such as fluidic transportation. Here, an optically powered soft material strip that can perform nonreciprocal, cilia-like, self-sustained oscillation under water is reported. The actuator is made of planar-aligned liquid crystal elastomer responding to visible light. Two laser beams from orthogonal directions allow for piecewise control over the strip deformation, enabling two self-shadowing effects coupled in one single material to yield nonreciprocal strokes. The nonreciprocity, stroke pattern and handedness are connected to the fluidic pumping efficiency, which can be controlled by the excitation conditions. Autonomous microfluidic pumping in clockwise and anticlockwise directions, translocation of a micro-object by liquid propulsion, and coupling between two oscillating strips through liquid medium interaction are demonstrated. The results offer new concepts for non-equilibrium soft actuators that can perform bio-like functions under water.

12.
Life Sci Space Res (Amst) ; 30: 24-28, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34281661

RESUMO

Semicarbazide-sensitive amine oxidase (SSAO) activity is known to be associated with certain pathologies including diabetes. In this study, SSAO expression and enzymatic activity in blood plasma of healthy rats were significantly upregulated under simulated microgravity (SMG) condition. Significant mortality was observed in SMG group of diabetic rats. Results indicate that microgravity might increase the risks of SSAO-associated alterations.


Assuntos
Amina Oxidase (contendo Cobre) , Diabetes Mellitus Experimental , Ausência de Peso , Animais , Dieta Hiperlipídica/efeitos adversos , Plasma , Ratos , Estreptozocina , Ausência de Peso/efeitos adversos
13.
J Proteomics ; 237: 104144, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33581354

RESUMO

Long-term spaceflight has always been challenging for astronauts due to the extremely complicated space environmental conditions, including microgravity, noise, confinement, and circadian rhythms disorders, which may cause adverse effects on astronauts' mental health, such as anxiety and depression. Unfortunately, so far, the underlying mechanism is not fully understood. Hence, a novel type of box and rat cage was designed and built in order to simulate complex space environment on the ground. After earth-based simulation for 21 days, the rats exhibited the depressive-like behavior according to the sucrose preference and forced swimming test. We applied label-free quantitative proteomics to explore the molecular mechanisms of depressive-like behavior through global changes in cortical protein abundance, given that the cortex is the hub of emotional management. The results revealed up-regulated spliceosome proteins in contrast to down-regulated oxidative phosphorylation (OXPHOS), glutamatergic, and GABAergic synapse related proteins in the simulated complex space environment (SCSE) group. Furthermore, PSD-95 protein was found down-regulated in mass spectrometry, reflecting its role in the psychopathology of depression, which was further validated by Western blotting. These findings provide valuable information to better understand the mechanisms of depressive-like behavior. SIGNIFICANCE: Quantitative proteomic analysis can quantify differentially abundant proteins related to a variety of potential signaling pathways in the rat cortex in the simulated complex space environment. These findings not only provide valuable information to better understand the mechanisms of depressive-like behavior, but also might offer the potential targets and develop countermeasures for the mental disorders to maintain the health of astronauts during the long-term spaceflight.


Assuntos
Voo Espacial , Ausência de Peso , Animais , Proteínas/análise , Proteômica , Ratos , Simulação de Ausência de Peso
14.
J Endod ; 47(5): 806-811, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33556424

RESUMO

INTRODUCTION: Dehydration has been considered as a potential contributor to vertical root fractures (VRFs) after root canal treatment (RCT). A loss of water could cause embrittlement of dentin and detrimental shrinkage strains. Senior patients have the highest risk of VRF. In this study, we characterized the spatial distribution in shrinkage of tooth roots with respect to donor age and prior RCT. METHODS: Single-rooted human teeth with and without prior RCT were collected from young (age <25 years) and old (age >60 years) adults. Transverse slices were sectioned from the apical, middle, and coronal thirds of the roots, and digital image correlation was used to evaluate shrinkage during free convection. Crack initiation and growth analysis was performed via optical microscopy, and bound water in dentin was characterized by Raman spectroscopy. RESULTS: The rate of shrinkage was significantly higher (p ≤ .05) in the apical third than in the middle and coronal thirds of all teeth regardless of donor age. The highest shrinkage strain occurred in the apical third of old donor teeth with prior RCT. In addition, the RCT-treated old teeth suffered the highest percentage of water loss with dehydration. Cracks initiated from the root surface and extended toward the canal with loss of water and shrinkage. CONCLUSIONS: The apical third undergoes significantly larger shrinkage strains with dehydration than the remainder of the root. Prior RCT exacerbates the extent of shrinkage, particularly in the teeth of seniors and after clinical function, which could increase the propensity for VRF.


Assuntos
Fraturas dos Dentes , Dente não Vital , Adulto , Dentina , Humanos , Pessoa de Meia-Idade , Fraturas dos Dentes/etiologia , Raiz Dentária , Água
15.
ACS Appl Mater Interfaces ; 11(39): 36044-36051, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31525959

RESUMO

A new water-responsive photonic coating based on a hygroscopic amphoteric poly(ampholyte) has been developed. The material consists of an interpenetrating network between the poly(ampholyte) and a cholesteric liquid crystalline polymer that reflects light. Swelling of this hybrid material upon contact with water causes a red-shift of the reflection band. As both cation and anion are incorporated in the ionic network, this coating possesses a high stability of its water responsiveness after prolonged and/or repeated exposure to water, even if the water contains dissolved ions. In addition, optimization of the water response of the coatings is demonstrated by changing the composition of the base cholesteric mixture, and color patterns were prepared through selective UV exposure.

16.
Diabetes Metab Res Rev ; 32(3): 325-32, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26409171

RESUMO

BACKGROUND: An elevated serum uric acid level has often been observed with type 2 diabetes or cancer progression. This study aimed to investigate the association between the serum uric acid, cancer incidence, and mortality in Chinese patients with type 2 diabetes. METHODS: A total of 8274 patients with type 2 diabetes from the Shanghai Diabetes Registry (SDR) participated. The follow-up rate was 85.4%. All subjects were divided into four groups according to the serum uric acid concentration: group 1 (1.0 mg/dL ≤ SUA < 3.0 mg/dL), group 2 (3.0 mg/dL ≤ SUA <5.0 mg/dL), group 3 (5.0 mg/dL ≤ SUA < 7.0 mg/dL), and group 4 (SUA ≥ 7.0 mg/dL). The primary outcome was the first diagnosis of any cancer. The secondary outcome was all-cause mortality. A Cox proportional hazards model was used to estimate the relative risks of cancer and death. RESULTS: One hundred thirty-seven men and 115 women had cancer by the end of the study. In women, group 1 had the lowest incidence rate of cancer at 30.3 cases per 10 000 person-years, followed by group 2 (48.2). The cancer incidence rates in groups 3 (80.4) and 4 (100.8) were significantly higher than in group 2 (p < 0.05). No significant differences were observed in the incidence of cancer in men (p = 0.76). The risks of overall mortality and death from cancer were not significantly different among the different serum uric acid groups in either sex (Pmale = 0.480, Pfemale = 0.075). CONCLUSION: In Chinese female diabetic patients, the incidence of cancer increased with serum uric acid levels.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Hiperuricemia/epidemiologia , Mortalidade/tendências , Neoplasias/epidemiologia , Idoso , China/epidemiologia , Diabetes Mellitus Tipo 2/mortalidade , Feminino , Humanos , Hiperuricemia/etiologia , Hiperuricemia/mortalidade , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Neoplasias/mortalidade , Prognóstico , Sistema de Registros , Fatores de Risco , Taxa de Sobrevida , Ácido Úrico/metabolismo
17.
Oxid Med Cell Longev ; 2015: 309125, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26257840

RESUMO

Organophosphate pesticides (OPs) are among the most widely used synthetic chemicals for the control of a wide variety of pests, and reactive oxygen species (ROS) caused by OPs may be involved in the toxicity of various pesticides. Previous studies have demonstrated that a reactivation of latent Epstein-Barr virus (EBV) could be induced by oxidative stress. In this study, we investigated whether OPs could reactivate EBV through ROS accumulation. The Raji cells were treated with chlorpyrifos (CPF), one of the most commonly used OPs. Oxidative stress indicators and the expression of the EBV immediate-early gene BZLF-1 were determined after CPF treatment. Our results show that CPF induces oxidative stress as evidenced by decreased malondialdehyde (MDA) level, accompanied by an increase in ROS production, DNA damage, glutathione (GSH) level, and superoxide dismutase (SOD) and catalase (CAT) activity. Moreover, CPF treatment significantly enhances the expression of BZLF-1, and the increased BZLF-1 expression was ameliorated by N-acetylcysteine (NAC) incubation. These results suggest that OPs could contribute to the reactivation of the EBV lytic cycle through ROS induction, a process that may play an important role in the development of EBV-associated diseases.


Assuntos
Clorpirifos/toxicidade , Herpesvirus Humano 4/efeitos dos fármacos , Inseticidas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Transativadores/metabolismo , Acetilcisteína/farmacologia , Catalase/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Herpesvirus Humano 4/metabolismo , Humanos , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Regulação para Cima/efeitos dos fármacos
18.
J Surg Res ; 199(2): 732-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26216750

RESUMO

BACKGROUND: Hyperbaric oxygen (HBO) improves skin flap function and inhibits partial necrosis induced by ischemia-reperfusion (I/R) injury. Our study aimed to evaluate the mechanism underlying HBO regulation of the antiapoptosis factors associated with I/R injury of skin flaps. METHODS: The rats were divided into sham surgery, I/R, and HBO groups. Rats from the HBO group received HBO preconditioning followed by I/R surgery. Blood perfusion of the skin flaps was measured with laser Doppler flowmeters. Tissue morphology and apoptosis were subsequently assessed based on hematoxylin-eosinhe and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. Protein expression of phosphorylated apoptosis signal-regulating kinase 1 (pASK-1), phosphorylated c-Jun N-terminal kinase (pJNK), B-cell lymphoma-2 (Bcl-2), and Bcl2-associated X protein (Bax) was examined by immunodetection, and Bcl-2 messenger RNA expression was detected by quantitative polymerase chain reaction. In addition, caspase-3 activity was also measured. RESULTS: The result of microcirculation analysis showed that the survival and blood perfusion rates significantly increased in the skin flap after HBO exposure. Terminal deoxynucleotidyl transferase dUTP nick-end labeling staining revealed that cell apoptosis was significantly attenuated in the HBO group. Furthermore, HBO preconditioning increased the expression of Bcl-2 and inhibited pASK-1, pJNK, and Bax expression as determined by both immunohistochemistry and Western blot. Caspase-3 activity and the Bax/Bcl-2 ratio declined in the HBO group. CONCLUSIONS: HBO preconditioning effectively ameliorates I/R injury by regulating the apoptosis signal-regulating kinase 1 and/or c-Jun N-terminal kinase pathway and anti- and proapoptosis factors.


Assuntos
Apoptose , Oxigenoterapia Hiperbárica , Precondicionamento Isquêmico/métodos , Traumatismo por Reperfusão/prevenção & controle , Pele/irrigação sanguínea , Animais , Caspase 3/metabolismo , Modelos Animais de Doenças , MAP Quinase Quinase Quinase 5/metabolismo , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Pele/metabolismo , Pele/patologia , Proteína X Associada a bcl-2/metabolismo
19.
Diabetes Technol Ther ; 17(4): 229-34, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25781235

RESUMO

BACKGROUND: Dyslipidemia is commonly seen in patients with type 2 diabetes mellitus (T2DM). The current study sought to compare the effects of nateglinide and acarbose, two antihyperglycemic agents, on both fasting and postprandial lipid profiles in Chinese subjects with T2DM. SUBJECTS AND METHODS: For this multicenter, open-label, randomized, active-controlled, parallel-group study, 103 antihyperglycemic agent-naive patients with T2DM were recruited from four hospitals in China. In total, 85 subjects (44 in the nateglinide group, 41 in the acarbose group) with a known complete lipid profile underwent the entire clinical trial and were included in the final analysis. Serum was collected in the fasting state and 30 and 120 min after a standardized meal (postprandial states) to measure the baseline lipid profiles; the same testing was performed upon completion of a 2-week course of nateglinide (120 mg three times a day) or acarbose (50 mg three times a day). RESULTS: Fasting triglyceride (TG) levels were significantly reduced by both nateglinide and acarbose (P<0.001), with acarbose providing a significantly more robust improvement (vs. nateglinide, P=0.005). Additionally, the TG levels at both postprandial times were significantly reduced by acarbose (P<0.001 at 30 min and P=0.002 at 120 min), whereas nateglinide treatment only significantly reduced the 30-min postprandial TG (P=0.029). Neither nateglinide nor acarbose treatment had significant impact on total cholesterol, high-density lipoprotein, low-density lipoprotein, or non-high-density lipoprotein cholesterol. CONCLUSIONS: Compared with nateglinide, acarbose has superior therapeutic efficacy for reducing fasting and postprandial TG levels in patients with T2DM.


Assuntos
Acarbose/uso terapêutico , Cicloexanos/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dislipidemias/tratamento farmacológico , Jejum/sangue , Hipoglicemiantes/uso terapêutico , Fenilalanina/análogos & derivados , Período Pós-Prandial , Adulto , China , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Dislipidemias/etiologia , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Nateglinida , Fenilalanina/uso terapêutico , Estudos Prospectivos , Fatores de Tempo , Triglicerídeos/sangue
20.
Diabetes Technol Ther ; 17(5): 320-6, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25759909

RESUMO

BACKGROUND: The goal of the present study was to explore the correlations of 1,5-anhydroglucitol (l,5-AG), glycated hemoglobin (HbA1c), and glycated albumin (GA) with insulin sensitivity and secretion. SUBJECTS AND METHODS: In total, 302 patients with newly diagnosed type 2 diabetes mellitus (166 men, 136 women) were enrolled in this study. The homeostasis model assessment for insulin resistance (HOMA-IR) and homeostasis model assessment for ß-cell function (HOMA-ß) were calculated to determine the basal insulin sensitivity and secretion. The insulinogenic index (IGI) was used to evaluate early-phase insulin secretion. 1,5-AG and GA were assayed via the enzymatic method, and HbA1c was detected by high-pressure liquid chromatography. RESULTS: Among all 302 subjects, the serum 1,5-AG level was 13.1±7.2 µg/mL, and the HbA1c and GA levels [median (interquartile range)] were 6.7% (6.2-7.3%) and 17.7% (16.0-19.5%), respectively. Increased 1,5-AG quartiles were accompanied by trends toward a decreased HOMA-IR and an increased HOMA-ß and IGI (for all trends, P<0.001). 1,5-AG was negatively associated with HOMA-IR (r=-0.200, P<0.001) and positively associated with HOMA-ß and IGI (r=0.210 and 0.413, respectively; both P<0.001). 1,5-AG was independently related to HOMA-IR and HOMA-ß and exhibited an independent positive association with IGI (standardized ß=0.242, P<0.001). Additionally, both HbA1c and GA were independently correlated with HOMA-IR and HOMA-ß. CONCLUSIONS: 1,5-AG is not only correlated with basal insulin sensitivity and secretion, but also closely associated with early-phase insulin secretion in Chinese patients with newly diagnosed type 2 diabetes mellitus.


Assuntos
Desoxiglucose/sangue , Diabetes Mellitus Tipo 2/sangue , Insulina/metabolismo , Adulto , Idoso , Povo Asiático , China , Diabetes Mellitus Tipo 2/etnologia , Feminino , Hemoglobinas Glicadas/análise , Produtos Finais de Glicação Avançada , Homeostase/fisiologia , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Secreção de Insulina , Células Secretoras de Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Albumina Sérica/análise , Albumina Sérica Glicada
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