RESUMEN
A simple method of fabricating hemispherical nanostructures on a curved aluminum rod surface was presented. In conventional methods of fabricating nanopatterns on a curved aluminum surface, mechanical or chemical processes have been widely used for the lens technologies. Such processes are not only expensive with long processing times, however, but they also involve local fabrication and are limited in the dimension size. In this paper, a method of fabricating hemispherical nanostructures on a curved aluminum surface is suggested for a functional three-dimensional (3D) master using a low-temperature and high-voltage (LTHV) anodizing method. By reducing the aluminum reaction rate under a low-temperature environment, the reaction current density can be remarkably reduced even though a high voltage was induced. Using the LTHV anodizing method, the hemispherical pattern size can be easily controlled with respect to voltage variations. The sizes of the hemispherical nanopatterns were about 150-300 nm. Using the LTHV anodizing process, hemispherical nanostructures can be obtained on a curved aluminum surface with controllable pattern sizes of 150-300 nm without defects such as burring from Joule's heat, micro-scratches, and cracks. A curved 3D hemispherical nanostructure may be used as a master in the roll-to-roll process.
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Enterococcus faecalis is a facultative anaerobic gram-positive commensal bacterium common in the gastrointestinal tract of animals and humans. This study aimed to investigate the protective effects of heat-killed E. faecalis EF-2001 (EF-2001) on acute gastric ulcer using a murine model of ethanol (EtOH)-induced acute gastric injury. EF-2001 (20, 40, and 80 mg/kg/day) was administered by oral gavage for 5 days before EtOH treatment (10 mL/kg body weight). EF-2001 effectively attenuated EtOH-induced gastric mucosal injury with reduced gastric mucosal ulcer and histological damage score. Pretreatment of EF-2001 markedly suppressed the phosphorylation of mitogen-activated protein kinases (MAPKs; ERK1/2, JNK, and p38MAPK). In addition, EF-2001 significantly inhibited phosphorylation of nuclear factor kappa B (NF-κB) and subsequently suppressed the upregulation of inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 in gastric tissues. Taken together, these results suggest that EF-2001 exerts a gastroprotective effect against acute gastric injury, and the underlying mechanism might be associated with the suppression of MAPKs and NF-κB signaling and consequent reduction of pro-inflammatory mediators or cytokines.
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Enterococcus faecalis , Úlcera Gástrica/prevención & control , Animales , Supervivencia Celular , Citocinas/genética , Etanol , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , Calor , Masculino , Ratones , Ratones Endogámicos ICR , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Células RAW 264.7 , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/genética , Úlcera Gástrica/patologíaRESUMEN
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Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Pérdida de Peso/fisiología , Adulto , Anciano , Índice de Masa Corporal , Estudios Transversales , Ejercicio Físico/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Estado Nutricional , República de Corea , Índice de Severidad de la EnfermedadRESUMEN
This study examined the relation between glycogen, lactate content and muscle fiber type composition, and evaluated their influence on postmortem glycolytic rate and meat quality. Muscle samples were classified based on their glycogen and lactate content at 45min postmortem. Muscles with low glycogen and high lactate levels showed low muscle pH(45min) and high R-values. However, muscles with low glycogen and lactate levels showed normal rates of postmortem glycolysis and normal meat quality. On the other hand, muscles with high glycogen and lactate content showed rapid postmortem glycolysis, paler surface color, higher drip loss, and higher extents of protein denaturation than muscles with high glycogen and low lactate content. These results may be partially explained by muscle fiber type composition. Muscles with low glycogen and lactate content at early postmortem are composed of significantly higher fiber type I and lower fiber type IIB as compared to muscles with high glycogen and lactate content.
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The purpose of this study was to compare the muscle histochemical characteristics and meat quality traits between Berkshire, Landrace, Yorkshire, and crossbred pigs. A total of 594 pigs were evaluated. A clear difference between histochemical properties was observed from the results for fiber type composition. In Berkshire pigs, the area percentage of type I fibers was higher (P<0.001) and that of type IIb fibers was lower (P<0.05) than those of other breeds. The muscle pH(45min) and pH(24h) were significantly higher in Berkshire pigs. Drip loss and color parameters were significantly different between the breeds (P<0.001). The Berkshire pigs, which showed the highest muscle pH and lowest drip loss and L(∗) values, contained a significantly higher percentage of type I fibers than the other breeds. By comparing the fiber type compositions of the different breeds, the results imply that the longissimus dorsi muscle of Berkshire pigs is more oxidative than that of other breeds. A high pH value in Berkshire pigs is due to a high percentage of type I fibers and a low percentage of type IIb fibers. Based on these results, we conclude that muscle fiber composition can explain in parts the variation of meat quality across and within breeds.
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OBJECTIVE: Although activation of protein kinase C (PKC) modulates the function of normal cardiac myocytes and likely plays a role in the pathogenesis of cardiomyopathic disease states, the molecular basis of PKC expression in human ventricle has not been examined in detail. METHODS: We have performed Western analysis and immunohistochemistry on explanted human cardiac tissue from nondiseased and diseased specimens using isoform-specific antibodies directed against all known PKC isozymes. RESULTS: In homogenates from left and right ventricle, all isoforms except PKC-gamma and theta were detected by immunoblotting, with confirmation using a second antibody directed against a different epitope when possible. For PKC-betaII, delta, and epsilon, data indicated that these isoforms were variably phosphorylated in vivo, resulting in multiple bands during immunoblotting. Because of potential antibody cross-reactivity, reverse transcriptase polymerase chain reaction (RT-PCR) was performed which confirmed expression of PKC-alpha, betaI, and zeta. Immunohistochemistry demonstrated that all isoforms detected in ventricular homogenate by Western analysis could be localized to cardiac myocytes. From a methodologic standpoint, significant degradation of PKC isoforms could be demonstrated when samples were either frozen or allowed to remain at room temperature, compared to immediate subcellular fractionation. CONCLUSIONS: These findings indicate that the PKC expression in human ventricular myocytes is remarkably diverse, with multiple conventional, novel, and atypical isoforms present, and highlight the importance of sample preparation in comparative studies of PKC isoform expression.
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Insuficiencia Cardíaca/enzimología , Isoenzimas/análisis , Miocardio/enzimología , Proteína Quinasa C/análisis , Adolescente , Adulto , Anciano , Western Blotting , Femenino , Ventrículos Cardíacos/enzimología , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Fosforilación , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
We tested the hypothesis that specific isoforms of protein kinase C (PKC) are responsible for modulation of Na+ current (I(Na)) derived from the human cardiac Na+ channel using activators and inhibitors selective for specific PKCs. Experimental results demonstrated that I(Na) suppression was mediated by activation of conventional PKCs (cPKCs) and possibly resulted from channel internalization. In the presence of cPKC inhibition, phorbol ester application unexpectedly increased Na+ current, an effect eliminated by inhibition of protein kinase A. These findings demonstrate complex modulation of cardiac I(Na) by protein kinases and provide further evidence that PKC isoforms have distinct protein targets.
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Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Miocardio/metabolismo , Proteína Quinasa C/fisiología , Canales de Sodio/metabolismo , Animales , Células Cultivadas , Concanavalina A/farmacología , Conductividad Eléctrica , Activación Enzimática , Humanos , Isoenzimas/fisiología , Cinética , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/fisiología , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C beta , Proteína Quinasa C-epsilon , Acetato de Tetradecanoilforbol/farmacología , XenopusRESUMEN
The cardiac Na+ current plays an important role in determining normal and abnormal impulse propagation in the heart. We have investigated the effects of protein kinase C (PKC) activation on the recombinant human cardiac Na+ channel (hH1) following heterologous expression in Xenopus laevis oocytes. Phorbol 12-myristate 13-acetate (PMA), which directly activates PKC, reduced current amplitude at all test potentials (43 +/- 12% at -10 mV). In contrast to the rat brain IIA (rBIIA) channel, there was no apparent change in either macroscopic Na+ current decay or the voltage dependence of channel gating. Further experiments indicate that the effects of PMA were mediated by PKC activation: (1) an inactive stereoisomer, 4 alpha-PMA, had no effect; (2) preincubation with the protein kinase inhibitor chelerythrine prevented the PMA effects; and (3) a hydrolyzable diacylglycerol analogue, 1-oleoyl-2-acetyl-glycerol, also reduced current (22 +/- 5%). In addition, when the alpha 1B-adrenergic receptor was coexpressed with hH1, the alpha-receptor agonist methoxamine reduced hH1 current (45 +/- 10%), an effect that could be eliminated by chelerythrine preincubation. When a conserved consensus PKC site (serine 1503) in the III-IV interdomain linker thought to be responsible for the PKC effects on rBIIA was mutated, PMA still reduced Na+ current, but the magnitude of the effect was smaller compared with that for the wild-type channel. Similar findings were obtained with alpha 1-receptor stimulation following receptor coexpression with the mutant channel. We conclude that activation of PKC modulates the human cardiac Na+ channel by at least two mechanisms, one similar to that seen with rat brain channels, involving a conserved putative PKC site, and a second more specific to the cardiac isoform.
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Activación del Canal Iónico/fisiología , Miocardio/metabolismo , Proteína Quinasa C/metabolismo , Canales de Sodio/fisiología , Alcaloides , Animales , Benzofenantridinas , Cricetinae , Diglicéridos/farmacología , Activación Enzimática , Humanos , Activación del Canal Iónico/efectos de los fármacos , Metoxamina/farmacología , Mutación , Técnicas de Placa-Clamp , Fenantridinas/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Receptores Adrenérgicos alfa 1/efectos de los fármacos , Receptores Adrenérgicos alfa 1/genética , Receptores Adrenérgicos alfa 1/fisiología , Canales de Sodio/efectos de los fármacos , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacología , Transfección , Xenopus laevisRESUMEN
Ehlers-Danlos syndrome type IV (EDS IV) is an autosomal dominant disorder characterized by fragile skin, blood vessels, and internal organs and associated with decreased production, secretion, or thermal stability of type III procollagen. Mutations in the gene for type III procollagen have been identified in patients exhibiting decreased secretion or thermal stability of the protein, but no defect has been elucidated to explain the decreased production of type III procollagen in some patients with EDS IV. We report on a patient with a moderate case of EDS IV who produced decreased amounts of type III procollagen despite normal levels of translatable type III procollagen mRNA. S1 nuclease analysis of the type III procollagen mRNA indicated a defect in the region encoding exon 27. Sequence analysis of cDNA clones and genomic fragments generated by polymerase chain reaction amplification revealed that sequences encoded by exon 27 were absent from 3 out of 5 cDNA clones and that a G at the +5 position of the splice donor site in intron 27 was changed to an A in one allele of the patient's type III procollagen gene. Using a cDNA-genomic DNA hybrid probe in S1 nuclease analysis, fragments consistent with mRNA species containing and lacking exon 27 were detected in a 1:1 ratio. Pulse label and chase experiments in the presence or absence of brefeldin A indicated that most of the type III procollagen molecules synthesized by the patient's fibroblasts were not secreted into the medium but were degraded in the endoplasmic reticulum-Golgi compartment by a nonlysosomal mechanism.