Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Medicine (Baltimore) ; 99(26): e20823, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590769

RESUMO

Gout is a chronic disease related to uric acid metabolism. It involves crystals of uric acid accumulating in the joints, causing joint pain and releasing cytokines that trigger inflammation. Inflammation is a key component in the pathogenesis of epilepsy. Thus, we conducted a cohort study to investigate if epilepsy is associated with gout and determine the risk of epilepsy in patients with gout.The gout cohort was obtained from the Registry of Catastrophic Illnesses Patient Database (RCIPD). We identified 104,238 patients who were aged 20 years or more and newly diagnosed with gout between 2000 and 2011 and 3 outpatient visits or history of gout-specific hospitalization between 2000 and 2011. Patients without gout were frequency matched with the gout cohort at a 2:1 ratio according to age, sex, comorbidities, and year of gout diagnosis.The gout cohort showed a 1.27-fold higher overall crude hazard ratio (HR) for epilepsy compared with the control cohort. After we adjusted the analyses by age, sex, and comorbidities the gout patients displayed an increased risk of epilepsy compared with the control group (adjusted HR = 1.25, 95% confidence interval = 1.15-1.36).This study revealed a significantly higher risk of epilepsy in patients with gout. It provides further evidence for the debate around the effect of gout on brain health.


Assuntos
Epilepsia/fisiopatologia , Gota/fisiopatologia , Adulto , Idoso , Estudos de Coortes , Correlação de Dados , Epilepsia/epidemiologia , Feminino , Gota/epidemiologia , Humanos , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros/estatística & dados numéricos , Fatores de Risco , Taiwan/epidemiologia
2.
Front Physiol ; 8: 576, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848450

RESUMO

FXYD proteins are important regulators of Na+/K+-ATPase (NKA) activity in mammals. As an inhabitant of estuaries, the pufferfish (Tetraodon nigroviridis) responds to ambient salinity changes with efficient osmoregulation, including alterations in branchial, and renal NKA activities. Previous studies on teleostean FXYDs have mainly focused on the expression and potential functions of FXYD proteins in gills. The goal of the present study was to elucidate the potential role of FXYD8, a member of the fish FXYD protein family, in the modulation of NKA activity in the kidneys of this euryhaline pufferfish by using molecular, biochemical, and physiological approaches. The results demonstrate that T. nigroviridis FXYD8 (TnFXYD8) interacts with NKA in renal tubules. Meanwhile, the protein expression of renal TnFXYD8 was found to be significantly upregulated in hyperosmotic seawater-acclimated pufferfish. Moreover, overexpression of TnFXYD8 in Xenopus oocytes decreased NKA activity. Our results suggest the FXYD8 is able to modulate NKA activity through inhibitory effects upon salinity challenge. The present study further extends our understanding of the functions of FXYD proteins, the regulators of NKA, in vertebrates.

3.
Antimicrob Agents Chemother ; 59(1): 721-3, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25367917

RESUMO

A salmonella genomic island, designated SGI11, was found in 18 of 26 multidrug-resistant Salmonella enterica serovar Typhi isolates from Bangladesh. SGI11 was an IS1 composite transposon and carried 7 resistance genes that conferred resistance to 5 first-line antimicrobials. Eleven of the 18 SGI11-carrying S. Typhi isolates had developed resistance to high levels of ciprofloxacin.


Assuntos
Cromossomos Bacterianos/genética , Salmonella typhi/efeitos dos fármacos , Antibacterianos/uso terapêutico , Bangladesh/epidemiologia , Elementos de DNA Transponíveis/genética , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos/genética , Humanos , Dados de Sequência Molecular , Salmonella typhi/genética , Febre Tifoide/tratamento farmacológico , Febre Tifoide/epidemiologia , Febre Tifoide/microbiologia
4.
Antimicrob Agents Chemother ; 58(11): 6501-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25136011

RESUMO

We characterized Salmonella enterica serovar Typhi isolates from Bangladesh, Indonesia, Taiwan, and Vietnam to investigate their genetic relatedness and antimicrobial resistance. The isolates from Bangladesh and Vietnam were genetically closely related but were distant from those from Indonesia and Taiwan. All but a few isolates from Indonesia and Taiwan were susceptible to all antimicrobials tested. The majority of isolates from Bangladesh and Vietnam were multidrug resistant (MDR) and belonged to the widespread haplotype H58 clone. IncHI1 plasmids were detected in all MDR S. Typhi isolates from Vietnam but in only 15% of MDR isolates from Bangladesh. Resistance genes in the majority of MDR S. Typhi isolates from Bangladesh should reside in the chromosome. Among the isolates from Bangladesh, 82% and 40% were resistant to various concentrations of nalidixic acid and ciprofloxacin, respectively. Several resistance mechanisms, including alterations in gyrase A, the presence of QnrS, and enhanced efflux pumps, were involved in the reduced susceptibility and resistance to fluoroquinolones. Intensive surveillance is necessary to monitor the spread of chromosome-mediated MDR and fluoroquinolone-resistant S. Typhi emerging in Bangladesh.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Salmonella typhi/efeitos dos fármacos , Salmonella typhi/genética , Bangladesh , Sequência de Bases , Proteínas de Transporte/genética , Ciprofloxacina/farmacologia , Genótipo , Humanos , Indonésia , Testes de Sensibilidade Microbiana , Ácido Nalidíxico/farmacologia , Filogenia , Plasmídeos/efeitos dos fármacos , Plasmídeos/genética , Polimorfismo de Nucleotídeo Único , Salmonella typhi/isolamento & purificação , Análise de Sequência de DNA , Taiwan , Febre Tifoide/tratamento farmacológico , Febre Tifoide/microbiologia , Vietnã
5.
Appl Opt ; 53(11): 2523-31, 2014 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-24787426

RESUMO

Numerical mold-flow simulations and experimental measurements for injection-molded lenses have been investigated in form accuracy on a two-cavity mold with various process conditions. First, form profiles of the molded lenses have been measured together with the corresponding simulated mold-temperature distribution and displacement distribution of the lens in the z direction. A flow-through type layout of cooling channels has been devised for balance of mold-temperature distribution in mold cavities with various parametric distances for assessments in uniformity of temperature distribution. Finally, a compression-molding process is proposed for the post-process of birefringence relaxation as well as adequate form accuracy of lenses. In conclusion, optimization of process parameters to achieve good form accuracy in a multicavity mold with symmetric geometry but nonuniform cooling conditions is difficult. A good design of cooling channels plus optimized process conditions could provide uniform mold-temperature distribution so that molded lenses of good quality would be possible. Then, the profile deviation of lenses could be further compensated by profile geometry corrections. In conclusion, the post-compression-molding process could make birefringence-free plastic lenses with good form accuracy.

6.
Biomaterials ; 31(32): 8419-25, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20701966

RESUMO

HeLa cells were incubated with neutron capture nuclei (boron-10 and gadolinium)-containing carbon nanoparticles, followed by irradiation of slow thermal neutron beam. Under a neutron flux of 6 x 10(11) n/cm(2) (or 10 min irradiation at a neutron flux of 1 x 10(9) n/cm(2) s), the percentages of acute cell death at 8 h after irradiation are 52, 55, and 28% for HeLa cells fed with BCo@CNPs, GdCo@CNPs, and Co@CNPs, respectively. The proliferation capability of the survived HeLa cells was also found to be significantly suppressed. At 48 h after neutron irradiation, the cell viability further decreases to 35 +/- 5% as compared to the control set receiving the same amount of neutron irradiation dose but in the absence of carbon nanoparticles. This work demonstrates "proof-of-concept" examples of neutron capture therapy using (10)B-, (157)Gd-, and (59)Co-containing carbon nanoparticles for effective destruction of cancer cells. It will also be reported the preparation and surface functionalization of boron or gadolinium doped core-shell cobalt/carbon nanoparticles (BCo@CNPs, GdCo@CNPs and Co@CNPs) using a modified DC pulsed arc discharge method, and their characterization by various spectroscopic measurements, including TEM, XRD, SQUID, FT-IR, etc. Tumor cell targeting ability was introduced by surface modification of these carbon nanoparticles with folate moieties.


Assuntos
Boro/uso terapêutico , Cobalto/uso terapêutico , Gadolínio/uso terapêutico , Nanopartículas/química , Neoplasias/radioterapia , Terapia por Captura de Nêutron/métodos , Boro/administração & dosagem , Terapia por Captura de Nêutron de Boro/métodos , Carbono/química , Sobrevivência Celular/efeitos da radiação , Cobalto/administração & dosagem , Gadolínio/administração & dosagem , Células HeLa , Humanos , Isótopos/administração & dosagem , Isótopos/uso terapêutico , Nanopartículas/ultraestrutura
7.
Langmuir ; 26(9): 6314-9, 2010 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-20356047

RESUMO

The roughness of a multiphase interface and the associated topography between silicone oil and an alcohol-based fluid were measured with an atomic force microscope (AFM) and compared with the results of calculations based upon a capillary-wave model. According to this theory, the interfacial roughness of a liquid-liquid interface depends on the density, interfacial tension, and temperature of the liquids. Test samples prepared with both silicone oil and an alcohol-based fluid at various volumetric ratios and controlled temperatures were carefully measured. The experimental results indicate that the interfacial roughness measured with an AFM was consistent with the capillary-wave model. The measured interfacial roughness is influenced mainly by the interfacial tension between the liquids and the temperature-driven Brownian motion of the molecules. Three-dimensional topographical pictures of the interfaces were constructed and archived digitally for subsequent investigation. By employing the outlined method, we examined the microscopic details of interfacial properties, with prospective applications in biochemical and biophysical research.

8.
Artigo em Inglês | MEDLINE | ID: mdl-19150505

RESUMO

Euryhaline tilapia (Oreochromis mossambicus) survived in brackish water (BW; 20 per thousand) but died in seawater (SW; 35 per thousand) within 6 h when transferred directly from fresh water (FW). The purpose of this study was to clarify responses in gills of FW tilapia to various hyperosmotic shocks induced by BW or SW. In FW-acclimated tilapia, scanning electron micrographs of gills revealed three subtypes of MR cell apical surfaces: wavy-convex (subtype I), shallow-basin (subtype II), and deep-hole (subtype III). Density of apical surfaces of mitochondrion-rich (MR) cell in gills of the BW-transfer tilapia decreased significantly within 3 h post-transfer due to disappearance of subtype I cells, but increased from 48 h post-transfer because of increasing density of subtype III cells. SW-transfer individuals, however, showed decreased density of MR cell openings after 1 h post-transfer because subtype I MR cell disappeared. On the other hand, relative branchial Na+/K+-ATPase (NKA) alpha1-subunit mRNA levels, protein abundance, and NKA activity of the BW-transfer group increased significantly at 6, 12, and 12 h post-transfer, respectively. In the SW-transfer group, relative mRNA and protein abundance of gill NKA alpha1-subunit did not change while NKA activity declined before dying in 5 h. Upon SW transfer, dramatic increases (nearly 2-fold) of plasma osmolality, [Na+], and [Cl(-)] were found prior to death. For the BW-transfer group, plasma osmolality was eventually controlled by 96 h post-transfer by enhancement of NKA expression and subtype III MR cell. The success or failure of NKA activation from gene to functional protein as well as the development of specific SW subtype in gills were crucial for the survival of euryhaline tilapia to various hyperosmotic shocks.


Assuntos
Brânquias/metabolismo , Estresse Fisiológico/fisiologia , Tilápia/metabolismo , Animais , Água Doce/química , Brânquias/citologia , Immunoblotting , Concentração Osmolar , Pressão Osmótica , Cloreto de Sódio/química , ATPase Trocadora de Sódio-Potássio/metabolismo
9.
J Exp Biol ; 211(Pt 23): 3750-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19011216

RESUMO

Na+/K+-ATPase (NKA) is a ubiquitous membrane-bound protein crucial for teleost osmoregulation. The enzyme is composed of two essential subunits, a catalytic alpha subunit and a glycosylated beta subunit which is responsible for membrane targeting of the enzyme. In mammals, seven FXYD members have been found. FXYD proteins have been identified as the regulatory protein of NKA in mammals and elasmobranchs, it is thus interesting to examine the expression and functions of FXYD protein in the euryhaline teleosts with salinity-dependent changes of gill NKA activity. The present study investigated the expression and distribution of the FXYD protein in gills of seawater (SW)- or freshwater (FW)-acclimated euryhaline pufferfish (Tetraodon nigroviridis). The full-length pufferfish FXYD gene (pFXYD) was confirmed by RT-PCR. pFXYD was found to be expressed in many organs including gills of both SW and FW pufferfish. pFXYD mRNA abundance in gills, determined by real-time PCR, was significantly higher in FW fish than in SW fish. An antiserum raised against a partial amino acid sequence of pFXYD was used for the immunoblots of gill homogenates and a major band at 13 kDa was detected. The relative amounts of pFXYD protein and mRNA in gills of SW and FW pufferfish were identical, but opposite to the expression levels of NKA. Immunofluorescent staining of frozen sections demonstrated that pFXYD was colocalized to NKA-immunoreactive cells in the gill filaments. In addition, interaction between pFXYD and NKA was demonstrated by co-immunoprecipitation. Taken together, salinity-dependent expression of pFXYD protein and NKA, as well as the evidence for their colocalization and interaction in pufferfish gills suggested that pFXYD regulates NKA activity in gills of euryhaline teleosts upon salinity challenge.


Assuntos
Região Branquial/metabolismo , Proteínas de Peixes/metabolismo , Expressão Gênica/efeitos dos fármacos , Brânquias/metabolismo , Cloreto de Sódio/farmacologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Tetraodontiformes/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Peixes/química , Immunoblotting , Dados de Sequência Molecular , Filogenia , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Tetraodontiformes/genética
10.
Appl Opt ; 47(12): 2017-27, 2008 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-18425174

RESUMO

Numerical simulations for mold-flow analysis and experimental measurements of injection-molded plastic lenses have been conducted for investigation of optical qualities, residual birefringence, and form accuracy resulting from various pertinent process conditions. First, residual birefringence distributions on the lens have been predicted and verified experimentally. Furthermore, full-scale factorial design of experiments was conducted to comprehend the influences of qualities, such as shear stresses, form accuracy, and volumetric deviation, on the measured primary or Seidel aberrations. In conclusion, residual birefringence induced by stresses represented by photoelasticity measurements agrees well with the numerical predictions and the experimental results indicate that the residual birefringence is mainly generated during the mold-filling stage. In addition, spherical aberration of the injection-molded plastic lenses is more sensitive to the pertinent qualities as compared to coma and astigmatism.

11.
Mol Reprod Dev ; 71(2): 186-96, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15791595

RESUMO

To study the regulation of embryonic development by Rho, we microinjected Clostridium botulinum C3-exoenzyme (C3) into zebrafish embryos. We found that C3 inhibited cytokinesis during early cleavages. C3 inhibition appeared to be specific on RhoA, since the constitutively active RhoA could partially rescued the C3-induced defects. Distributions of actin and the cleavage furrow associated beta-catenin were disrupted by C3. Belbbistatin, a myosin II inhibitor, also caused blastomeres disintegration. It suggested that Rho mediates cytokinesis via cleavage furrow protein assembly and actomyosin ring constriction. Furthermore, C3 blocked cellular movements during epiboly and gastrulation as evident by the impairment on no tail and goosecoid expression in blastoderm front runner cells and the dorsal lip of blastopore, respectively. Y-27632, an antagonist of Rho-associated kinase (ROK/ROCK), had the similar inhibitory effects on zebrafish development as the C3 treatments. Taken together, these results suggest that Rho mediates cleavage furrow protein assembly during cytokinesis and cellular migration during epiboly and gastrulation via a ROK/ROCK-dependent pathway.


Assuntos
ADP Ribose Transferases/administração & dosagem , Toxinas Botulínicas/administração & dosagem , Movimento Celular/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Peixe-Zebra/embriologia , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Movimento Celular/fisiologia , Embrião não Mamífero/citologia , Embrião não Mamífero/embriologia , Gástrula/citologia , Gástrula/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Quinases Associadas a rho
12.
Toxicon ; 45(3): 303-8, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15683868

RESUMO

Microcystin-LR (MC-LR), a cyanobacterial toxin, is a potent inhibitor of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A). PP1 and PP2A are critical regulators in embryonic development. However, the effects of MC-LR in embryonic development have been controversial. MC-LR has been demonstrated to be highly toxic in medaka, but not in zebrafish or rabbit embryos. The causes of difference may be due to membrane impermeability that impaired the delivery of MC-LR into cytoplasm of zebrafish and rabbit embryos. Therefore, we microinjected MC-LR directly into developing zebrafish embryos and investigated the effects of MC-LR on embryonic development. We demonstrated that MC-LR induced the lethality of zebrafish embryos in a dose- and time-dependent manner. MC-LR also induced the loss of blastomere coherence via the interference of beta-catenin and cadherins distributions. Furthermore, the MC-LR treated fry revealed various developmental defects. These results suggested that MC-LR might affect the phosphorylation equilibrium of signaling molecules, including beta-catenin and cadherins, required early in zebrafish embryonic development.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Toxinas Marinhas/toxicidade , Peptídeos Cíclicos/toxicidade , Animais , Blastômeros/efeitos dos fármacos , Caderinas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Relação Dose-Resposta a Droga , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Microcistinas , Fatores de Tempo , Transativadores/metabolismo , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra , beta Catenina
13.
Biosens Bioelectron ; 20(1): 115-21, 2004 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-15142583

RESUMO

MHD micro-pumps circumvent the wear and fatigue caused by high pressure-drop across the check valves of mechanical micro-pumps in micro-fluidic systems. Early analyses of the fluid flow for MHD micro-pumps were mostly made possible by the Poiseuille flow theory; however, this conventional laminar approach cannot illustrate the effects of various channel sizes and shapes. This paper, therefore, presents a simplified MHD flow model based upon steady state, incompressible and fully developed laminar flow theory to investigate the characteristics of a MHD pump. Inside the pump, flowing along the channel is the electrically conducting fluid flowing driven by the Lorentz forces in the direction perpendicular to both dc magnetic field and applied electric currents. The Lorentz forces were converted into a hydrostatic pressure gradient in the momentum equations of the MHD channel flow model. The numerical simulations conducted with the explicit finite difference method show that the channel dimensions and the induced Lorentz forces have significant influences on the flow velocity profile. Furthermore, the simulation results agree well with the experimental results published by other researchers.


Assuntos
Desenho Assistido por Computador , Análise de Falha de Equipamento/métodos , Análise de Injeção de Fluxo/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Microfluídica/instrumentação , Microfluídica/métodos , Modelos Teóricos , Simulação por Computador , Desenho de Equipamento , Análise de Injeção de Fluxo/métodos , Técnicas Analíticas Microfluídicas/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Condutividade Térmica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...