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The objective of this study was to assess the associations of presenilin 1 (PS1) 1/2, angiotensin I-converting enzyme (ACE) insertion/deletion (I/D), and low-density lipoprotein receptor-related protein (LRP) C/T polymorphisms with the risk of Alzheimer's disease (AD) in the Chinese population. PS1 1/2, ACE I/D, and LRP C/T, which are commonly investigated polymorphisms, were evaluated to obtain summary estimates regarding their associations with AD. In total, the data from 24 studies (2611 patients with AD and 2822 control subjects from 23 provinces and special districts in China) that were obtained from the Chinese Biomedicine Database, China National Knowledge Infrastructure, PubMed, and Medline were included. Different models (i.e., dominant, recessive, etc.) of these polymorphisms were analyzed using the Cochrane Review Manager. Statistically significant associations among patients with AD for the 1/1 genotype of the PS1 1/2 polymorphism [odds ratio (OR) = 1.77, 95% confidence interval (CI) = 1.03-3.04; P = 0.04] and the I/I genotype of the ACE I/D polymorphism (OR = 2.44, 95%CI = 1.78-3.35; P < 0.01) were identified. Statistically significant associations were also found for the PS1 1/2 polymorphism in both the dominant and recessive genetic models, whereas no association was found for the LRP C/T polymorphism. All studies exhibited heterogeneity (P < 0.05). This meta-analysis suggests that the 1/1 genotype of the PS1 1/2 polymorphism and the I/I genotype of the ACE I/D polymorphism are significantly associated with an increased risk of AD in the Chinese population.
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Enfermedad de Alzheimer/genética , Predisposición Genética a la Enfermedad , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/genética , Peptidil-Dipeptidasa A/genética , Presenilina-1/genética , Anciano , Anciano de 80 o más Años , Alelos , Enfermedad de Alzheimer/patología , Pueblo Asiatico , China , Femenino , Estudios de Asociación Genética , Humanos , Mutación INDEL/genética , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
The aim of this study was to explore the effect of atorvastatin intervention on plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) and inflammatory cytokine levels in patients with heart failure (HF). One hundred and twenty-three HF patients were selected from our hospital and randomly divided into control (N = 61) and observation (N = 62) groups; the former received conventional treatment, while the latter were given conventional treatment combined with atorvastatin. Plasma NT-proBNP, inflammatory cytokines [high-sensitive C-reactive protein (hs-CRP), interleukin (IL)-6, IL-10] and cardiac function [left ventricular end-diastolic dimension (LVEDD), left ventricular ejection fraction (LVEF), end-diastolic maximum flow rate ratio (E/A)] were compared among groups. The effective rate of treating HF significantly increased after atorvastatin treatment. The plasma NT-proBNP, IL-6, IL-10, hs-CRP, and LVEDD levels significantly decreased (P < 0.05), while the LVEF and E/A levels significantly increased (P < 0.05) in the observation group compared to the control group and before intervention. The NT-proBNP and cytokine levels significantly differed among patients with different classes of heart function (P < 0.05); the NT-proBNP and cytokine levels increased with the severity of heart function. Pearson's correlation analysis revealed a negative correlation between the NT-proBNP and inflammatory cytokine levels and LVEF and E/A values, and a positive correlation between these factors and LVEDD (P < 0.05). In conclusion, atorvastatin significantly improves cardiac function; the mechanism atorvastatin action was related to the decrease in plasma NT-proBNP and inflammatory cytokine levels.
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Atorvastatina/uso terapéutico , Citocinas/sangre , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Mediadores de Inflamación/sangre , Péptido Natriurético Encefálico/sangre , Fragmentos de Péptidos/sangre , Adulto , Anciano , Biomarcadores , Estudios de Casos y Controles , Ecocardiografía , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Pruebas de Función Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
The goal of this study was to investigate damaged liver function after chemotherapy in hepatitis B virus (HBV) carriers with non-Hodgkin lymphoma (NHL) and to evaluate risk factors associated with a high risk of damaged liver function. Clinical histories of 134 HBV carriers with NHL who were treated with chemotherapy were obtained and analyzed for the occurrence of damaged liver function and other related high-risk factors. Analysis showed that 76 patients (56.7%) had damaged liver function after chemotherapy: 6 patients (7.9%) had I degree, 17 patients (22.4%) had II degree, 20 patients (26.3%) had III degree, and 33 patients (43.4%) had IV degree damage. After treatment, 18 patients (23.7%) continued to receive chemotherapy according to their original schedule, 39 patients (51.3%) delayed chemotherapy, 16 patients (21.1%) stopped chemotherapy, and 3 patients (3.9%) died. Analysis of a binary multivariate logistic regression model showed that administration of steroids was a high-risk factor for damaged liver function after chemotherapy in NHL patients. The incidence of damaged liver function after chemotherapy is high among HBV carriers with NHL; therefore, administration of steroid chemotherapy is a high-risk factor.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Hepatitis B/fisiopatología , Hígado/fisiopatología , Linfoma no Hodgkin/tratamiento farmacológico , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/virología , Niño , Femenino , Hepatitis B/complicaciones , Hepatitis B/virología , Virus de la Hepatitis B/fisiología , Interacciones Huésped-Patógeno , Humanos , Hígado/patología , Hígado/virología , Modelos Logísticos , Linfoma no Hodgkin/complicaciones , Masculino , Persona de Mediana Edad , Análisis Multivariante , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
ZnMgO nanowalls were prepared by plasma-assisted molecular beam epitaxy without a catalyst on c-Al2O3 substrate. The obtained nanowalls have preferred orientation along c axis. The nanowalls are about 10 to 20 nm in thickness and about 50 nm in height. Only Zn, Mg, O and Al signals are detected in the nanowalls from the energy dispersive spectroscopy (EDS). The Mg content is about 3% in ZnMgO nanowalls. The room temperature photoluminescence (PL) spectra shows the emission peak of the ZnMgO nanowalls at 3.346 eV. The origin of the ultraviolet emission is discussed with the help of temperature-dependent PL spectra. The ultraviolet emission band is free exiton recombination observed in the low temperature PL spectra (at 81 K). We also observe the free-to-acceptor (FA) emission of the ZnMgO nanowalls. The acceptor binding energy obtained from photoluminescence studies is about 123 meV. The results show that Mg doping leads to an increase of the acceptor binding energy. The possible growth mechanism of the ZnMgO nanowall networks was discussed.
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This paper describes ZnO nanocrystals embedded in BaF2 matrices by the magnetron sputtering method in an attempt to use fluoride as a shell layer to embed ZnO nanocrystals core. BaF2 is a wide-band gap material, and can confine carriers in the ZnO films. As a result, the exciton emission intensity should be enhanced. The sample was annealed at 773 K, and X-ray diffraction (XRD) results showed that ZnO nanocrystals with wurtzite structure were embedded in BaF2 matrices. Raman-scattering spectra also confirmed the formation of ZnO nanoparticles. Abnormal longitudinal-optical (LO) phonon-dominant multiphonon Raman scattering was observed in the sample. Room-temperature photoluminescence (PL) spectra showed an ultraviolet emission peak at 374 nm. The origin of the ultraviolet emission is discussed here with the help of temperature-dependent PL spectra. The ultraviolet emission band was a mixture of free exciton and bound exciton recombination observed in the low temperature PL spectra (at 77 K). Abnormal temperature dependence of ultraviolet near-band-edge emission-integrated intensity of the sample was observed. The band tail state was observed in the absorption spectra, illustrating that the impurity-related defects were caused by the shell of the BaF2 grain layer. For comparison, ZnO films on BaF2 substrates were also fabricated by the magnetron sputtering method, and the same measurement methods were used.
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The macroscale properties of polymer-matrix composites depend immensely on the quality of the interaction between the reinforcement phase and the bulk polymer. This work presents a method to improve the interfacial adhesion between metal-oxides and a polymer matrix by performing surface-initiated polymerization (SIP) by way of a biomimetic initiator. The initiator was modeled after 3,4-dihydroxy-L-phenylalanine (dopa), an amino acid that is highly concentrated in mussel foot adhesive proteins. Mechanical pull out tests of NiTi and Ti-6Al-4V wires from poly (methyl methacrylate) (PMMA) were performed to directly test the interfacial adhesion. These tests demonstrated improvements in maximum interfacial shear stress of 116% for SIP-modified NiTi wires and 60% for SIP-modified Ti-6Al-4V wires over unmodified specimens. Polymer chain growth from the metal oxides was validated using x-ray photoemission spectroscopy (XPS), ellipsometry, scanning electron microscopy (SEM), and contact angle analysis.
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OBJECTIVE: To identify the expression changes of microRNA 93 (miR-93) in oxygen-glucose deprivation/reoxygenation (OGD/R) injury in cardiomyocytes and its mechanism of mediating OGD/R and inducing apoptosis. MATERIALS AND METHODS: Primary cardiomyocytes were extracted and OGD/R model in cardiomyocytes was established in vitro. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expressions of miR-93, and Western blot assay was applied to measure the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and caspase-3. Flow cytometry was utilized to examine the cardiomyocyte apoptosis rate. RESULTS: The apoptosis rate was increased after OGD/R in cardiomyocytes, accompanied by remarkable rise of miR-93 expression. After transfection of miR-93 antagomir, the apoptosis rate of cardiomyocyte induced by OGD/R was down-regulated, and the expression of cleaved caspase-3 was decreased. Meanwhile, the results of qRT-PCR and Western blot showed that the levels of Nrf2 mRNA and protein expression were up-regulated after the miR-93 level was inhibited, and luciferase reporter assay affirmed that Nrf2 was a target molecule for OGD/R-induced apoptosis mediated by miR-93. CONCLUSIONS: miR-93 mediates OGD/R-induced hypoxia/reoxygenation injury apoptosis in cells by targeting Nrf2.
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MicroARNs/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Regiones no Traducidas 3' , Animales , Antagomirs/metabolismo , Secuencia de Bases , Caspasa 3/metabolismo , Hipoxia de la Célula , Células Cultivadas , Regulación hacia Abajo , Glucosa/metabolismo , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Factor 2 Relacionado con NF-E2/química , Factor 2 Relacionado con NF-E2/genética , Ratas , Alineación de Secuencia , Regulación hacia ArribaRESUMEN
OBJECTIVE: The relationship between hypertension and the mechanism of the expression of T-lymphocyte Kv1.3 channels in vascular aging has been analyzed in this study based on the gender and age matches' principle. PATIENTS AND METHODS: Thirty patients have been consecutively chosen with vascular aging caused by hypertension (group A), while 30 cases of high blood pressure not merged with vascular aging (group B) were chosen, and 30 cases of healthy volunteers (group C), conforming to gender and age 1:1 and the closest matching principle, were studied. The aim of this study was to separate the peripheral blood mononuclear cells and give intervention of 0.2 nmol/L ANGII to CD4 + T-lymphocytes, and store them in the incubator 48 h. The difference of Kv1.3 channel current of CD4 + T-lymphocyte, mRNA, angiotensin receptor (AT1R) protein mRNA, and IFN-γ density has also been compared. RESULTS: The membrane capacitance, peak current, and current density of group A, are higher than those of the other two groups, and the differences have statistical significance (p<0.05). After adding ANGII intervention to group A, the expression levels of T-lymphocyte Kv1.3 potassium channels mRNA, AT1R mRNA, and IFN-γ are significantly increased, so that the difference has statistical significance p<0.05, while the other two groups have no significant change (p>0.05). The levels of Kv1.3 potassium channels, AT1R mRNA, and IFN-γ of group A before and after the intervention are significantly higher than those of the other two groups, and the differences are statistically significant (p<0.05). CONCLUSIONS: Vascular aging caused by hypertension may be linked to the increase of Kv1.3 potassium channel activity of T-lymphocyte, while ANGII can improve the high expression of Kv1.3 potassium channel and AT1R, to stimulate lymph cells to secrete IFN-γ.
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Vasos Sanguíneos/crecimiento & desarrollo , Vasos Sanguíneos/fisiopatología , Hipertensión/fisiopatología , Adulto , Anciano , Envejecimiento , Vasos Sanguíneos/diagnóstico por imagen , Linfocitos T CD4-Positivos/metabolismo , Femenino , Humanos , Canal de Potasio Kv1.3/metabolismo , Masculino , Persona de Mediana Edad , Receptor de Angiotensina Tipo 1/biosíntesis , Receptor de Angiotensina Tipo 1/metabolismo , Caracteres Sexuales , Linfocitos T/metabolismo , Ultrasonografía DopplerRESUMEN
Luminescence properties of nanosized zinc oxide (ZnO) colloids depend greatly on their surface properties, which are in turn largely determined by the method of preparation. ZnO nanoparticles in the size range from 3 to 9 nm were prepared by addition of tetramethylammonium hydroxide ((CH3)4NOH) to an ethanolic zinc acetate solution. X-ray diffraction (XRD) indicates nanocrystalline ZnO membranes with polycrystalline hexagonal wurtzite structure. The ZnO membranes have a strong visible-emission intensity and the intensity depends upon hydrolysis time. The infrared spectra imply a variety of forms of zinc acetate complexes present on the surface of ZnO particles. The effect of the ZnO membrane surface properties on photoluminescence is discussed.
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Colloidal ZnO particles with narrow size distribution were prepared via a sol-gel process by base-catalyzed hydrolysis of zinc acetate. The morphology of ordered arrays of the particles was recorded by SEM. SEM also reveals that these uniform particles were composed of tiny ZnO subunits (singlets) sized of several nanometers. The size of the singlets, which is confirmed by X-ray diffraction and UV-vis absorption spectra, increases as the aging time is prolonged. The size-selective formation of colloids by aggregation of nanosized subunits is proposed to consist of two-stage growth by nucleation of nanosized crystalline primary particles and their subsequent aggregation into polycrystalline secondary colloids. The aggregates are all spherical because the internal rearrangement processes are fast enough. The ZnO colloids, i.e., the aggregates, tend to self-assemble into well-ordered hexagonal close-packed structures. Room-temperature photoluminescence was characterized for green and aged ZnO.
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Mg(x)Zn(1-x)O ternary alloy nanocrystals with hexagonal wurtzite structures were fabricated by using the sol-gel method. X-ray diffraction patterns, UV-vis absorption spectra, and photoluminescence spectra were used to characterize the structural and optical properties of the nanocrystals. For as-prepared nanocrystals, the band gap increases with increasing Mg content. Weak excitonic emission with strong deep-level emission related to oxygen vacancy and interface defects is observed in the photoluminescence spectra at room temperature. Thermal annealing in oxygen was used to decrease the number of defects and to improve the quality of the nanocrystals. In terms of XRD results, the grain sizes of nanocrystals increase with increasing annealing temperature and the lattice constants of alloy are smaller than those of pure ZnO. The band gap becomes narrower with increasing annealing temperature. For Mg(x)Zn(1-x)O nanocrystals (x=0.03-0.15) annealed at temperatures ranging from 500 to 1000 degrees C, intense near-band-edge (NBE) emissions and weak deep-level (DL) emissions are observed. Consequently, the quality of Mg(x)Zn(1-x)O nanocrystals can be improved by thermal annealing.
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ZnO hexagonal prisms have been grown from poly (vinylpyrrolidone)-assisted electrochemical assembly onto p-type Si (111) substrate. These ZnO prisms arrays are highly (0002) orientated. The (0001) end facets and {1010} side facets of the hexagonal prisms are well defined. The photoluminescence (PL) spectrum of these ZnO prisms shows an intense ultraviolet near band-gap emission with a full width at half maximum of 86 meV at room temperature. The low-temperature PL spectrum is split into well-resolved free and bound exciton emission lines. The temperature dependence of the exciton emission intensities shows a nonmonotonic decaying behavior, which can be explained by the existence of interfacial states.
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Self-assembled zinc oxide (ZnO) and indium-doping zinc oxide (ZnO:In) nanorod thin films were synthesized on quartz substrates without catalyst in aqueous solution by sol-gel method. The samples were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), Raman-scattering spectroscopy, room-temperature photoluminescence (PL) spectra, and temperature-dependent PL spectra measurements. XRD and Raman spectra illustrated that there were no single In2O3 phase in ZnO lattice after indium doping. The PL spectra of ZnO showed a strong UV emission band located at 394 nm and a very weak visible emission associated with deep-level defects. Indium incorporation induced the shift of optical band gap, quenching of the near-band-edge photoluminescence and enhanced LO mode multiphonon resonant Raman scattering in ZnO crystals at different temperatures. Abnormal temperature dependence of UV emission integrated intensity of ZnO and ZnO:In samples is observed. The local state emission peak of ZnO:In samples at 3.37 eV is observed in low-temperature PL spectra. The near-band-edge emission peak at room temperature was a mixture of excitons and impurity-related transitions for both of two samples.