Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Child Psychiatry Hum Dev ; 51(6): 969-977, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32166459

RESUMO

This study sought to identify subgroups of attention-deficit hyperactivity disorder (ADHD) defined by specific patterns of emotional and behavioral symptoms according to the parent-rated Child Behavior Checklist (CBCL). Our clinical sample comprised 314 children (aged 4 to 15 years) diagnosed with ADHD according to the DSM-5. In addition, comorbid psychiatric disorders, general functioning, and medication status were assessed. Cluster analysis was performed on the CBCL syndrome subscales and yielded a solution with four distinct subgroups. The "High internalizing/externalizing" group displayed an overlap between internalizing and externalizing problems in the CBCL profile. In addition, the "High internalizing/externalizing" group revealed a high rate of comorbid autism spectrum disorder and elevated autistic traits. The "Inattention and internalizing" group revealed a high rate of the predominantly inattentive presentation according to ADHD specifier from the DSM-5. The "Aggression and externalizing" group revealed a high rate of comorbid oppositional defiant disorder and conduct disorder. The "Less psychopathology" group scored low on all syndrome scales. Children with ADHD were subdivided into four distinct subgroups characterized by psychopathological patterns, with and without internalizing and externalizing problems. The overlap between internalizing and externalizing problems may be mediated with emotional dysregulation and associated neurobiological bases.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Lista de Checagem/estatística & dados numéricos , Transtornos do Comportamento Infantil/diagnóstico , Adolescente , Agressão/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/psicologia , Criança , Transtornos do Comportamento Infantil/psicologia , Pré-Escolar , Comorbidade , Transtorno da Conduta/diagnóstico , Transtorno da Conduta/psicologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Poder Familiar/psicologia , Psicopatologia
2.
Langmuir ; 35(33): 10920-10926, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31340122

RESUMO

The emulsifying and dispersing mechanisms of oil-in-water emulsions stabilized by 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO)-oxidized cellulose nanofibers (CNFs) have been investigated. The emulsifying mechanism was studied by changing the oil/water interfacial tension from 8.5 to 53.3 mN/m using various types of oils. The results showed that the higher the oil/water interfacial tension, the greater is the amount of CNFs adsorbed at the oil/water interface, making the CNF-adsorbed oil-in-water emulsions thermodynamically more stable. Moreover, the amount of CNFs adsorbed on the surfaces of the oil droplets increased with increasing interfacial area. The dispersion stability of the oil droplets was dominated by the CNF concentration in the water phase. Above the critical concentration (0.15% w/w), the CNFs formed network structures in the water phase, and the emulsion was effectively stabilized against creaming. Emulsion formation and the CNF network structures in the emulsion were visualized by cryo-scanning electron microscopy.

3.
Mol Cell ; 41(1): 56-66, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21211723

RESUMO

Heterochromatin impacts various nuclear processes by providing a recruiting platform for diverse chromosomal proteins. In fission yeast, HP1 proteins Chp2 and Swi6, which bind to methylated histone H3 lysine 9, associate with SHREC (Snf2/HDAC repressor complex) and Clr6 histone deacetylases (HDACs) involved in heterochromatic silencing. However, heterochromatic silencing machinery is not fully defined. We describe a histone chaperone complex containing Asf1 and HIRA that spreads across silenced domains via its association with Swi6 to enforce transcriptional silencing. Asf1 functions in concert with a Clr6 HDAC complex to silence heterochromatic repeats, and it suppresses antisense transcription by promoting histone deacetylation. Furthermore, we demonstrate that Asf1 and SHREC facilitate nucleosome occupancy at heterochromatic regions but TFIIIC transcription factor binding sites within boundary elements are refractory to these factors. These analyses uncover a role for Asf1 in global histone deacetylation and suggest that HP1-associated histone chaperone promotes nucleosome occupancy to assemble repressive heterochromatin.


Assuntos
Inativação Gênica , Histonas/metabolismo , Chaperonas Moleculares/fisiologia , Proteínas de Schizosaccharomyces pombe/fisiologia , Schizosaccharomyces/genética , Fatores de Transcrição/fisiologia , Acetilação , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/fisiologia , Montagem e Desmontagem da Cromatina , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/fisiologia , Epigênese Genética , Heterocromatina/metabolismo , Chaperonas Moleculares/metabolismo , Nucleossomos/metabolismo , RNA Antissenso/metabolismo , Recombinação Genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Fatores de Transcrição/metabolismo
4.
Ann Bot ; 117(3): 457-63, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26818592

RESUMO

BACKGROUND AND AIMS: When the orientation of the stems of conifers departs from the vertical as a result of environmental influences, conifers form compression wood that results in restoration of verticality. It is well known that intercellular spaces are formed between tracheids in compression wood, but the function of these spaces remains to be clarified. In the present study, we evaluated the impact of these spaces in artificially induced compression wood in Chamaecyparis obtusa seedlings. METHODS: We monitored the presence or absence of liquid in the intercellular spaces of differentiating xylem by cryo-scanning electron microscopy. In addition, we analysed the relationship between intercellular spaces and the hydraulic properties of the compression wood. KEY RESULTS: Initially, we detected small intercellular spaces with liquid in regions in which the profiles of tracheids were not rounded in transverse surfaces, indicating that the intercellular spaces had originally contained no gases. In the regions where tracheids had formed secondary walls, we found that some intercellular spaces had lost their liquid. Cavitation of intercellular spaces would affect hydraulic conductivity as a consequence of the induction of cavitation in neighbouring tracheids. CONCLUSIONS: Our observations suggest that cavitation of intercellular spaces is the critical event that affects not only the functions of intercellular spaces but also the hydraulic properties of compression wood.


Assuntos
Chamaecyparis/fisiologia , Espaço Extracelular/metabolismo , Plântula/fisiologia , Água/metabolismo , Madeira/fisiologia , Microscopia de Fluorescência , Plântula/ultraestrutura , Madeira/ultraestrutura
5.
J Plant Res ; 129(5): 873-881, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27294967

RESUMO

Elucidation of the mechanism of adsorption of particles suspended in the gas-phase (aerosol) to the outer surfaces of leaves provides useful information for understanding the mechanisms of the effect of aerosol particles on the growth and physiological functions of trees. In the present study, we examined the localization of artificially deposited sub-micron-sized carbon-based particles on the surfaces of needles of Cryptomeria japonica, a typical Japanese coniferous tree species, by field-emission scanning electron microscopy. The clusters (aggregates) of carbon-based particles were deposited on the needle surface regions where epicuticular wax crystals were sparsely distributed. By contrast, no clusters of the particles were found on the needle surface regions with dense distribution of epicuticular wax crystals. Number of clusters of carbon-based particles per unit area showed statistically significant differences between regions with sparse epicuticular wax crystals and those with dense epicuticular wax crystals. These results suggest that epicuticular wax crystals affect distribution of carbon-based particles on needles. Therefore, densely distributed epicuticular wax crystals might prevent the deposition of sub-micron-sized carbon-based particles on the surfaces of needles of Cryptomeria japonica to retain the function of stomata.


Assuntos
Aerossóis/farmacologia , Carbono/farmacologia , Cryptomeria/química , Epiderme Vegetal/química , Folhas de Planta/química , Ceras/química , Cryptomeria/efeitos dos fármacos , Cristalização , Tamanho da Partícula , Epiderme Vegetal/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/ultraestrutura
7.
Ann Bot ; 110(4): 875-85, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22843340

RESUMO

BACKGROUND AND AIMS: Latewood formation in conifers occurs during the later part of the growing season, when the cell division activity of the cambium declines. Changes in temperature might be important for wood formation in trees. Therefore, the effects of a rapid decrease in temperature on cellular morphology of tracheids were investigated in localized heating-induced cambial reactivation in Cryptomeria japonica trees and in Abies firma seedlings. METHODS: Electric heating tape and heating ribbon were wrapped on the stems of C. japonica trees and A. firma seedlings. Heating was discontinued when 11 or 12 and eight or nine radial files of differentiating and differentiated tracheids had been produced in C. japonica and A. firma stems, respectively. Tracheid diameter, cell wall thickness, percentage of cell wall area and percentage of lumen area were determined by image analysis of transverse sections and scanning electron microscopy. KEY RESULTS: Localized heating induced earlier cambial reactivation and xylem differentiation in stems of C. japonica and A. firma as compared with non-heated stems. One week after cessation of heating, there were no obvious changes in the dimensions of the differentiating tracheids in the samples from adult C. japonica. In contrast, tracheids with a smaller diameter were observed in A. firma seedlings after 1 week of cessation of heating. Two or three weeks after cessation of heating, tracheids with reduced diameters and thickened cell walls were found. The results showed that the rapid decrease in temperature produced slender tracheids with obvious thickening of cell walls that resembled latewood cells. CONCLUSIONS: The results suggest that a localized decrease in temperature of stems induces changes in the diameter and cell wall thickness of differentiating tracheids, indicating that cambium and its derivatives can respond directly to changes in temperature.


Assuntos
Abies/crescimento & desenvolvimento , Câmbio/crescimento & desenvolvimento , Cryptomeria/crescimento & desenvolvimento , Temperatura , Abies/citologia , Câmbio/citologia , Divisão Celular , Parede Celular/metabolismo , Cryptomeria/citologia , Temperatura Alta , Caules de Planta/citologia , Caules de Planta/crescimento & desenvolvimento , Estações do Ano , Plântula/citologia , Plântula/crescimento & desenvolvimento , Fatores de Tempo , Árvores , Madeira , Xilema/citologia , Xilema/crescimento & desenvolvimento
8.
Nature ; 442(7100): 312-6, 2006 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-16732292

RESUMO

Post-translational modification of chromatin has profound effects on many biological processes including transcriptional regulation, heterochromatin organization, and X-chromosome inactivation. Recent studies indicate that methylation on specific histone lysine (K) residues participates in many of these processes. Lysine methylation occurs in three distinct states, having either one (me1), two (me2) or three (me3) methyl groups attached to the amine group of the lysine side chain. These differences in modification state have an important role in defining how methylated chromatin is recognized and interpreted. Until recently, histone lysine methylation was considered a stable modification, but the identification of histone demethylase enzymes has demonstrated the reversibility of this epigenetic mark. So far, all characterized histone demethylases show enzymatic activity towards lysine residues modified in the me1 or me2 state, leaving open the possibility that me3 constitutes an irreversible modification. Here we demonstrate that JHDM3A (jumonji C (JmjC)-domain-containing histone demethylase 3A; also known as JMJD2A) is capable of removing the me3 group from modified H3 lysine 9 (H3K9) and H3 lysine 36 (H3K36). Overexpression of JHDM3A abrogates recruitment of HP1 (heterochromatin protein 1) to heterochromatin, indicating a role for JHDM3A in antagonizing methylated H3K9 nucleated events. siRNA-mediated knockdown of JHDM3A leads to increased levels of H3K9 methylation and upregulation of a JHDM3A target gene, ASCL2, indicating that JHDM3A may function in euchromatin to remove histone methylation marks that are associated with active transcription.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Histonas/química , Histonas/metabolismo , Lisina/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Animais , Homólogo 5 da Proteína Cromobox , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Heterocromatina/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji , Lisina/química , Metilação , Camundongos , Oxirredutases N-Desmetilantes , Estrutura Terciária de Proteína , Proteínas Repressoras/química , Proteínas Repressoras/genética , Fatores de Transcrição/química , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Transcrição Gênica
9.
J Biol Chem ; 285(10): 7374-83, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20042601

RESUMO

Iron- and 2-oxoglutarate-dependent dioxygenases are a diverse family of non-heme iron enzymes that catalyze various important oxidations in cells. A key structural motif of these dioxygenases is a facial triad of 2-histidines-1-carboxylate that coordinates the Fe(II) at the catalytic site. Using histone demethylase JMJD1A and DNA repair enzyme ABH2 as examples, we show that this family of dioxygenases is highly sensitive to inhibition by carcinogenic nickel ions. We find that, with iron, the 50% inhibitory concentrations of nickel (IC(50) [Ni(II)]) are 25 microm for JMJD1A and 7.5 microm for ABH2. Without iron, JMJD1A is 10 times more sensitive to nickel inhibition with an IC(50) [Ni(II)] of 2.5 microm, and approximately one molecule of Ni(II) inhibits one molecule of JMJD1A, suggesting that nickel causes inhibition by replacing the iron. Furthermore, nickel-bound JMJD1A is not reactivated by excessive iron even up to a 2 mm concentration. Using x-ray absorption spectroscopy, we demonstrate that nickel binds to the same site in ABH2 as iron, and replacement of the iron by nickel does not prevent the binding of the cofactor 2-oxoglutarate. Finally, we show that nickel ions target and inhibit JMJD1A in intact cells, and disruption of the iron-binding site decreases binding of nickel ions to ABH2 in intact cells. Together, our results reveal that the members of this dioxygenase family are specific targets for nickel ions in cells. Inhibition of these dioxygenases by nickel is likely to have widespread impacts on cells (e.g. impaired epigenetic programs and DNA repair) and may eventually lead to cancer development.


Assuntos
Enzimas Reparadoras do DNA , Dioxigenases , Inibidores Enzimáticos/química , Ferro/química , Isoenzimas , Histona Desmetilases com o Domínio Jumonji , Níquel/química , Homólogo AlkB 2 da Dioxigenase Dependente de alfa-Cetoglutarato , Calorimetria , Domínio Catalítico , Linhagem Celular , Enzimas Reparadoras do DNA/química , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Dioxigenases/química , Dioxigenases/genética , Dioxigenases/metabolismo , Inibidores Enzimáticos/metabolismo , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Histona Desmetilases com o Domínio Jumonji/química , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Níquel/metabolismo , Espectroscopia por Absorção de Raios X
10.
Neurol Clin Pract ; 11(5): 398-405, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34840866

RESUMO

OBJECTIVES: To determine the neurodevelopmental outcomes of very-low-birth-weight infants (VLBWIs, birth weight <1,500 g) after 9 years of follow-up. METHODS: This study prospectively recruited 224 VLBWIs born from 2003 to 2009 in Kyushu University Hospital, Japan. Comorbidities of neurocognitive impairment, epilepsy, and autism spectrum disorder or attention-deficit hyperactivity disorder (ASD/ADHD) were assessed at age 3, 6, and 9 years. RESULTS: Neurodevelopmental profiles were obtained from 185 (83%), 150 (67%), and 119 (53%) participants at age 3, 6, and 9 years, respectively. At age 9 years, 25 (21%) VLBWIs showed intelligence quotient (IQ) <70, 11 (9%) developed epilepsy, and 14 (12%) had a diagnosis of ASD/ADHD. The prevalence of epilepsy was higher in children with an IQ <70 at age 9 years than in those with an IQ ≥70 (44% vs 0%). In contrast, ASD/ADHD appeared at similar frequencies in children with an IQ <70 (16%) and ≥70 (11%). Perinatal complications and severe brain lesions on MRI were considered common perinatal risks for developmental delay and epilepsy but not for ASD/ADHD. Male sex was identified as a unique risk factor for ASD/ADHD. CONCLUSION: These data suggest that VLBWIs showed a higher prevalence of developmental delay, epilepsy, and ASD/ADHD at age 9 years than the general population. Distinct mechanisms might be involved in the pathogenic process of ASD/ADHD from those of developmental delay and epilepsy.

11.
Nihon Ronen Igakkai Zasshi ; 46(3): 259-63, 2009 May.
Artigo em Japonês | MEDLINE | ID: mdl-19521047

RESUMO

A 78-year-old man who suffered from syncope and light-headedness during straining. The patient visited to our department for evaluation of his symptom. Cardiac auscultation revealed a grade II/IV systolic murmur along the left parasternal border. Electrocardiography showed T wave inversion at the right precordial leads. Echocardiography demonstrated an unruptured aneurysm originating at the sinus of Valsalva protruding into the right ventricular outflow tract. Cardiac cathtererization demonstrated a pressure gradient of 34 mmHg between the right ventricular cavity and pulmonary artery with a large aneurysm originating from the right coronary cusp. Because of his low activity of daily living owing to old cerebral infarction, we managed the patient conservatively.


Assuntos
Aneurisma Aórtico/diagnóstico , Seio Aórtico , Síncope/complicações , Idoso , Humanos , Achados Incidentais , Masculino
12.
J Clin Invest ; 113(2): 253-64, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14722617

RESUMO

The principal effect of TGF-beta1 on mesenchymal cells is its stimulation of ECM synthesis. Previous reports indicated the significance of the autocrine TGF-beta loop in the pathogenesis of scleroderma. In this study, we focused on Smad7 and Smurfs, principal molecules in the negative regulation of TGF-beta signaling, to further understand the autocrine TGF-beta loop in scleroderma. Scleroderma fibroblasts exhibited increased Smad7 levels compared with normal fibroblasts in vivo and in vitro. Smad7 constitutively formed a complex with the TGF-beta receptors, and the inhibitory effect of Smad7 on the promoter activity of human alpha2(I) collagen and 3TP-lux was completely impaired in scleroderma fibroblasts. Furthermore, the protein stability of TGF-beta receptor type I was significantly increased in scleroderma fibroblasts compared with normal fibroblasts. There was no significant difference in Smurf1 and Smurf2 levels between normal and scleroderma fibroblasts, and the transiently overexpressed Smurf1 and/or Smurf2 did not affect TGF-beta receptor type I protein levels in scleroderma fibroblasts. These results indicate that the impaired Smad7-Smurf-mediated inhibitory effect on TGF-beta signaling might contribute to maintaining the autocrine TGF-beta loop in scleroderma fibroblasts. To our knowledge, this is the first report of a disturbed negative regulation of TGF-beta signaling in fibrotic disorders.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Transativadores/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases/fisiologia , Northern Blotting , Western Blotting , Células Cultivadas , Colágeno/metabolismo , Colágeno Tipo I , Proteínas de Ligação a DNA/metabolismo , Densitometria , Fibroblastos/metabolismo , Humanos , Immunoblotting , Imuno-Histoquímica , Microscopia de Fluorescência , Oligonucleotídeos/genética , Fosforilação , Plasmídeos/metabolismo , Testes de Precipitina , RNA/metabolismo , RNA Mensageiro/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Escleroderma Sistêmico/metabolismo , Transdução de Sinais , Proteína Smad7 , Fatores de Tempo , Transativadores/metabolismo , Transfecção , Fator de Crescimento Transformador beta1 , Ubiquitina-Proteína Ligases/metabolismo
13.
Nucleic Acids Res ; 33(11): 3540-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15972796

RESUMO

In this study, we clarified the molecular mechanism(s) underlying the regulation of matrix metalloproteinase (MMP)-1 gene by hepatocyte growth factor (HGF) in cultured human dermal fibroblasts. HGF induced MMP-1 protein as well as mRNA at a transcriptional level via extracellular signal-regulated kinase (ERK) signaling pathway. The region in the MMP-1 promoter mediating the inducible responsiveness to HGF, defined by the transient transfection analysis of the serial 5' deletion constructs, contained an Ets binding site. Mutation of this Ets binding site abrogated the HGF-inducible promoter activity. Ets1 up-regulated the expression of MMP-1 promoter activity, whereas Fli1 had antagonistic effects on them. After HGF treatment, the protein level and the binding activity of Ets1 was increased and those of Fli1 was decreased, which were canceled by PD98059. These results suggest that HGF up-regulates MMP-1 expression via ERK signaling pathway through the balance of Ets1 and Fli1, which may be a novel mechanism of regulating MMP-1 gene expression.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Fibroblastos/enzimologia , Fator de Crescimento de Hepatócito/farmacologia , Sistema de Sinalização das MAP Quinases , Metaloproteinase 1 da Matriz/genética , Proteínas Proto-Oncogênicas/fisiologia , Transativadores/fisiologia , Fatores de Transcrição/fisiologia , Derme/citologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Flavonoides/farmacologia , Regulação Enzimológica da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 1 da Matriz/biossíntese , Regiões Promotoras Genéticas , Inibidores de Proteínas Quinases/farmacologia , Proteína Proto-Oncogênica c-ets-1 , Proteína Proto-Oncogênica c-fli-1 , Proteínas Proto-Oncogênicas c-ets , RNA Mensageiro/metabolismo , Regulação para Cima
14.
Nucleic Acids Res ; 33(4): 1337-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15741186

RESUMO

We investigated the mechanisms by which protein kinase C (PKC) regulates the expression of the alpha2(I) collagen gene in normal dermal fibroblasts. Reduction of PKC-alpha activity by treatment with Gö697-6 or by overexpression of a dominant negative (DN) mutant form decreased alpha2(I) collagen gene expression. This decrease required a sequence element in the collagen promoter that contains Sp1/Sp3 binding sites. Reduction of PKC-delta activity by rottlerin or overexpression of DN PKC-delta also decreased alpha2(I) collagen gene expression. This effect required a separate sequence element containing Sp1/Sp3-binding sites and an Ets-binding site. In both cases, point mutations within the response elements abrogated the response to PKC inhibition. Forced overexpression of Sp1 rescued the PKC inhibitor-mediated reduction in collagen protein expression. A DNA affinity precipitation assay revealed that inhibition of PKC-delta by rottlerin increased the binding activity of endogenous Fli1 and decreased that of Ets1. On the other hand, TGF-beta1, which increased the expression of PKC-delta, had the opposite effect, increasing the binding activity of Ets1 and decreasing that of Fli1. Our results suggest that PKC-delta is involved in the regulation of the alpha2(I) collagen gene in the presence or absence of TGF-beta. Alteration of the balance of Ets1 and Fli1 may be a novel mechanism regulating alpha2(I) collagen expression.


Assuntos
Colágeno Tipo I/genética , Derme/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Proteína Quinase C/metabolismo , Transdução de Sinais , Carbazóis/farmacologia , Células Cultivadas , Colágeno Tipo I/biossíntese , Regulação para Baixo , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Humanos , Indóis/farmacologia , Regiões Promotoras Genéticas , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/fisiologia , Proteína Quinase C-delta , Inibidores de Proteínas Quinases/farmacologia , Fatores de Transcrição/fisiologia , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta1
15.
Cryo Letters ; 28(2): 77-81, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17522726

RESUMO

In previous studies, xylem parenchyma cells (XPCs) in the boreal softwood species larch, which has thick and rigid walls similar to those of XPCs in boreal hardwood species, were shown to respond to subfreezing temperature by deep supercooling during summer but change their freezing behavior to extracellular freezing during winter. In this study, we re-examined freezing behavior of XPCs in larch by observation of deep etching of frozen samples as well as observation of re-warmed samples after freezing using a cryo-scanning electron microscope. The results showed that XPCs in larch adapts to subfreezing temperature by deep supercooling throughout all seasons. Such freezing behavior is the same as that of XPCs in boreal hardwood species.


Assuntos
Temperatura Baixa , Microscopia Crioeletrônica/métodos , Larix/citologia , Xilema/citologia , Aclimatação/fisiologia , Parede Celular/fisiologia , Parede Celular/ultraestrutura , Congelamento , Larix/fisiologia , Larix/ultraestrutura , Microscopia Eletrônica de Varredura/métodos , Estações do Ano , Xilema/fisiologia , Xilema/ultraestrutura
16.
Indian Heart J ; 69(6): 714-719, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29174247

RESUMO

BACKGROUND: Ventricular fibrillation and atrial fibrillation are well-known arrhythmias in patients with Brugada syndrome. This study evaluated the characteristics of the atrial arrhythmogenic substrate using the signal-averaged electrogram (SAECG) in patients with Brugada syndrome. METHODS: SAECGs were performed during normal sinus rhythm in 23 normal volunteers (control group), 21 patients with paroxysmal atrial fibrillation (PAF; PAF group), and 21 with Brugada syndrome (Brugada group). RESULTS: The filtered P wave duration (fPd) in the control, Brugada, and PAF groups was 113.9±12.9ms, 125.3±15.0ms, and 137.1±16.3ms, respectively. The fPd in the PAF group was significantly longer compared to that in the control and Brugada groups (p<0.05). The fPd in the Brugada group was significantly longer than that in the control group (p<0.05) and significantly shorter than that in the PAF group (p<0.05). CONCLUSION: Patients with Brugada syndrome had abnormal P waves on the SAECG. The abnormal P waves on the SAECG in Brugada syndrome patients may have intermediate characteristics between control and PAF patients.


Assuntos
Síndrome de Brugada/fisiopatologia , Eletrocardiografia/métodos , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca/fisiologia , Síndrome de Brugada/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Intern Med ; 56(7): 749-753, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28381739

RESUMO

Objectives The fractional flow reserve (FFR) is an index of the severity of coronary stenosis that has been clinically validated in several studies. The instantaneous wave-free ratio (iFR) and the resting distal coronary artery pressure/aortic pressure (Pd/Pa) are nonhyperemic pressure-derived indices of the severity of stenosis. This study sought to examine the diagnostic accuracy of the iFR and resting Pd/Pa with respect to hyperemic FFR. Methods Following an intracoronary injection of papaverine, the iFR, resting Pd/Pa, and FFR were continuously measured in 123 lesions in 103 patients with stable coronary disease. Results The iFR and resting Pd/Pa values were strongly correlated with the FFR (R=0.794, p<0.001, R=0.832, p<0.0001, respectively). A receiver operator curve (ROC) analysis revealed that the optimal iFR cut-off value for predicting an FFR of <0.80 was 0.89 (AUC 0.901, sensitivity 84.1%, specificity 80.0%, positive predictive value 69.8%, negative predictive value 90.0%, diagnostic accuracy 81.3%), while the optimal resting Pd/Pa cut-off value was 0.92 (AUC 0.925, sensitivity 90.9%, specificity 78.5%, positive predictive value 70.2%, negative predictive value 93.9%, diagnostic accuracy 82.9%). The lesions with an iFR value of ≤0.89 and a Pd/Pa value of ≤0.92 were defined as double-positive lesions, while the lesions with an iFR value of >0.89 and a Pd/Pa value of >0.92 were defined as double-negative lesions. In these 109 lesions, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 92.3%, 82.9%, 75.0%, 95.1%, and 86.2%, respectively. Conclusion This analysis demonstrated that the iFR and resting Pd/Pa were strongly correlated with the FFR and that the diagnostic accuracy of the iFR was similar to that of the resting Pd/Pa. The diagnostic accuracy can be improved with the use of both the iFR and the resting Pd/Pa.


Assuntos
Aorta/fisiologia , Pressão Arterial/fisiologia , Estenose Coronária/diagnóstico , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Idoso , Angiografia Coronária , Doença da Artéria Coronariana , Feminino , Coração , Humanos , Hiperemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Papaverina/farmacologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Vasodilatadores/farmacologia
18.
Intern Med ; 56(3): 253-257, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28154267

RESUMO

Objective Measuring the fractional flow reserve (FFR) requires the induction of coronary hyperemia, usually with adenosine, adenosine triphosphate (ATP), or papaverine. However, adenosine can induce rhythmic complications, and intracoronary boluses of papaverine that prolong the QT interval can cause ventricular tachycardia. Injection of contrast media, which is routinely performed to validate the FFR guidewire placement, also induces hyperemia and may be an alternative method of measuring the FFR. We evaluated the diagnostic accuracy of the FFR after contrast hyperemia (FFRcont) compared to FFR evaluated after intracoronary papaverine (FFRpp). Methods This study included 109 lesions in 93 patients (mean age 70.4±8.7 years) with stable coronary disease. The FFR was measured as follows: 1) baseline pressure value; 2) FFRcont after intracoronary contrast injection (iopamidol, 8 mL for left coronary artery [LCA] or 6 mL for right coronary artery [RCA]); 3) FFRpp after intracoronary injection of papaverine (12 mg for LCA or 8 mg for RCA). Results FFRcont values were strongly correlated with FFRpp (R=0.940, p<0.0001; FFRpp = FFRcont ×1.007-0.032). The best cut-off point in the receiver operator curve analysis for predicting a FFRpp <0.80 was 0.82 (area under the curve =0.980; sensitivity 95.1%, specificity 91.2%, positive predictive value 86.7%, negative predictive value 96.9%). Conclusion FFRcont is highly accurate for predicting FFRpp. An FFRcont threshold value of 0.82 provides excellent sensitivity and a negative predictive value. FFRcont is an alternative method of inducing hyperemia.


Assuntos
Meios de Contraste/administração & dosagem , Doença da Artéria Coronariana/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Hiperemia/induzido quimicamente , Vasodilatadores/administração & dosagem , Adenosina/administração & dosagem , Idoso , Angiografia Coronária , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Hiperemia/fisiopatologia , Infusões Intravenosas , Masculino , Papaverina/administração & dosagem , Valor Preditivo dos Testes , Índice de Gravidade de Doença
19.
Clin Case Rep ; 5(11): 1826-1829, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29152279

RESUMO

Ganglionated plexus (GP) plays an important role in the initiation and maintenance of atrial fibrillation (AF). The GP ablation has been found to be effective for AF treatment. In this case, we reported an AF case in which the pulmonary vein (PV) potentials of the anterior region of the left superior PV were eliminated by an inferior right GP ablation.

20.
J Invest Dermatol ; 126(3): 551-60, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16374482

RESUMO

In this study, we examined the genes targeted by IL-13 in human dermal fibroblasts using a cDNA microarray. We focused on the tenascin-C (TN-C) gene, which was identified as one of the genes induced by IL-13. IL-13 induced transcriptional activity of TN-C. IL-13-mediated TN-C expression was inhibited by treatment with wortmannin or LY294002, or Calphostin C. IL-13 induced the phosphorylation of the phosphoinositide 3-kinase (PI3K) regulatory subunit p85, induced tyrosine phosphorylation of Akt, upregulated Akt kinase activity, and activated protein kinase C (PKC)-delta and -epsilon. The IL-13-induced increase in TN-C protein expression was abrogated by the transfection of a dominant-negative mutant of Akt, PKC-delta, or PKC-epsilon. In conclusion, we showed that the PI3K/Akt and/or PKC signaling pathways are essential for the IL-13-mediated increase in TN-C. Both serum levels of IL-13 and the expression levels of TN-C in the dermis are increased in patients with systemic sclerosis. Our findings suggest that the expression of TN-C is upregulated in this disease due to IL-13 signaling, and that a blockade of the PI3K or PKC signaling pathway may also have therapeutic value by reducing the amount of TN-C produced during fibrosis.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-13/farmacologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteína Quinase C/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia , Pele/metabolismo , Tenascina/genética , Androstadienos/farmacologia , Células Cultivadas , Cromonas/farmacologia , Fibroblastos/metabolismo , Humanos , Morfolinas/farmacologia , Naftalenos/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Pele/citologia , Regulação para Cima , Wortmanina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA