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1.
Regul Toxicol Pharmacol ; 88: 238-251, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28634147

RESUMO

With the aim of reconsidering ICH S7B and E14 guidelines, a new in vitro assay system has been subjected to worldwide validation to establish a better prediction platform for potential drug-induced QT prolongation and the consequent TdP in clinical practice. In Japan, CSAHi HEART team has been working on hiPS-CMs in the MEA (hiPS-CMs/MEA) under a standardized protocol and found no inter-facility or lot-to-lot variability for proarrhythmic risk assessment of 7 reference compounds. In this study, we evaluated the responses of hiPS-CMs/MEA to another 31 reference compounds associated with cardiac toxicities, and gene expression to further clarify the electrophysiological characteristics over the course of culture period. The hiPS-CMs/MEA assay accurately predicted reference compounds potential for arrhythmogenesis, and yielded results that showed better correlation with target concentrations of QTc prolongation or TdP in clinical setting than other current in vitro and in vivo assays. Gene expression analyses revealed consistent profiles in all samples within and among the testing facilities. This report would provide CiPA with informative guidance on the use of the hiPS-CMs/MEA assay, and promote the establishment of a new paradigm, beyond conventional in vitro and in vivo assays for cardiac safety assessment of new drugs.


Assuntos
Síndrome do QT Longo/induzido quimicamente , Miócitos Cardíacos/efeitos dos fármacos , Arritmias Cardíacas/induzido quimicamente , Cardiotônicos/toxicidade , Eletrodos , Expressão Gênica , Guias como Assunto , Humanos , Técnicas In Vitro , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/fisiologia , Ativação do Canal Iônico/genética , Japão , Contração Miocárdica/genética , Miócitos Cardíacos/fisiologia
2.
Regul Toxicol Pharmacol ; 77: 75-86, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26884090

RESUMO

In vitro screening of hERG channels are recommended under ICH S7B guidelines to predict drug-induced QT prolongation and Torsade de Pointes (TdP), whereas proarrhythmia is known to be evoked by blockage of other ion channels involved in cardiac contraction and compensation mechanisms. A consortium for drug safety assessment using human iPS cells-derived cardiomyocytes (hiPS-CMs), CSAHi, has been organized to establish a novel in vitro test system that would enable better prediction of drug-induced proarrhythmia and QT prolongation. Here we report the inter-facility and cells lot-to-lot variability evaluated with FPDc (corrected field potential duration), FPDc10 (10% FPDc change concentration), beat rate and incidence of arrhythmia-like waveform or arrest on hiPS-CMs in a multi-electrode array system. Arrhythmia-like waveforms were evident for all test compounds, other than chromanol 293B, that evoked FPDc prolongation in this system and are reported to induce TdP in clinical practice. There was no apparent cells lot-to-lot variability, while inter-facility variabilities were limited within ranges from 3.9- to 20-folds for FPDc10 and about 10-folds for the minimum concentration inducing arrhythmia-like waveform or arrests. In conclusion, the new assay model reported here would enable accurate prediction of a drug potential for proarrhythmia.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Diferenciação Celular , Canal de Potássio ERG1/antagonistas & inibidores , Frequência Cardíaca/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Microeletrodos , Miócitos Cardíacos/efeitos dos fármacos , Bloqueadores dos Canais de Potássio/toxicidade , Testes de Toxicidade/instrumentação , Potenciais de Ação , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatologia , Bioensaio , Cardiotoxicidade , Técnicas de Cultura de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Canal de Potássio ERG1/metabolismo , Desenho de Equipamento , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Japão , Miócitos Cardíacos/metabolismo , Observação , Reprodutibilidade dos Testes , Medição de Risco , Testes de Toxicidade/métodos , Testes de Toxicidade/normas
3.
Exp Eye Res ; 93(1): 75-81, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21600896

RESUMO

Glutamate-mediated excitotoxicity, mainly induced by N-methyl-d-aspartate (NMDA) receptors, is known to cause retinal ganglion cell death in retinal ischemia, glaucoma, and several other retinal diseases. We evaluated the effects of ß-estradiol (E2) against a single intravitreal injection of NMDA using a functional and morphological approach. Male rats were randomly divided into 3 treatment groups: (1) Control; (2) NMDA (intravitreal injection of 5 mM NMDA); and (3) NMDA + E2 (intravitreal injection of 5 mM NMDA and pretreatment with subcutaneous E2 implantation). Seven days after NMDA injection, full-field electroretinograms (ERGs) and quantitative morphological analyses using transverse sections of the retina were conducted. In the NMDA group, full-field ERGs showed reductions in the amplitudes of the negative-scotopic threshold response, rod response b-wave, oscillatory potentials, flicker response second b-wave and cone response b-wave. Morphological evaluations of transverse sections of the retina demonstrated a reduction in the thickness of the inner plexiform layer, increases in the thickness of the outer plexiform and outer nuclear layers, and a loss of cells in the ganglion cell layer. In the NMDA + E2 group, pretreatment with E2 prevented the aggravations in the amplitudes of the ERGs except for oscillatory potential 2 (OP2); however, no morphological differences between the NMDA and NMDA + E2 groups were seen. These findings indicate that E2 can protect retinal function against NMDA-induced neurotoxicity. In addition, these indications suggested that the effect of E2 may have therapeutic benefits in NMDA related diseases, such as retinal ischemia and glaucoma.


Assuntos
Estradiol/farmacologia , Estrogênios/farmacologia , Agonistas de Aminoácidos Excitatórios/toxicidade , N-Metilaspartato/toxicidade , Fármacos Neuroprotetores/farmacologia , Retina/efeitos dos fármacos , Células Ganglionares da Retina/efeitos dos fármacos , Animais , Peso Corporal , Contagem de Células , Eletrorretinografia/efeitos dos fármacos , Estradiol/sangue , Estrogênios/sangue , Injeções Intravítreas , Masculino , Ratos , Ratos Sprague-Dawley , Retina/fisiopatologia , Células Ganglionares da Retina/fisiologia
4.
Front Psychiatry ; 10: 932, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998153

RESUMO

Objective: Although family involvement in the treatment of obsessive-compulsive disorder (OCD) produces a reduction in OCD symptoms and has significant effects on global functioning, few studies have focused on family intervention as part of OCD treatment in Japan. This study aims to examine the feasibility and efficacy of the family-based exposure and response prevention (FERP) program for adult patients with OCD and their family members. Design: Randomized controlled pilot study. Methods: A total of 18 outpatients aged 18-65 years with a primary diagnosis of OCD and one family member of each patient were randomized to an intervention group or a control group (1:1). The intervention group received the FERP program, which consisted of 16 weekly face-to-face cognitive behavioral therapy (CBT) sessions, including eight joint sessions with family members, in addition to treatment-as-usual (TAU). The control group received TAU alone. The primary outcome was the alleviation of OCD symptoms, as measured by changes in the total Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score from baseline to posttreatment. Analyses were provided on an intention-to-treat basis, and linear mixed models were used to test for significant group differences. Results: After 16 weeks, patients allocated to the FERP program showed improvement in OCD symptom severity, as measured by the total change score of the Y-BOCS (Hedges' g = -1.58), as compared to the control group. Two patients (22.2%) in the FERP group reached remission, and five patients (55.6%) in the FERP group achieved treatment response. Clinical global improvement measured by the FAS-SR scores, K6 scores, and CGI-S scores was also observed (Hedges' g = -1.35, -1.25, and -1.26, respectively) in the FERP group as compared to the control group. The dropout rate from the study was low (n = 2, 11.8%), and no adverse events were reported in the FERP group. Conclusion: Our results suggest that FERP may be an effective program for reducing patients' OCD symptoms. Clinical Trial Registration: www.umin.ac.jp/ctr/, identifier UMIN000021763.

5.
Anal Sci ; 23(3): 249-51, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17372363

RESUMO

The fluorescence of 4-(4'-dimethylamino)styryl-1-methylpyridinium (C1SP) was enhanced by more than 33-fold by complexation with beta-cyclodextrin (beta-CD) bearing a naphthalene, pyrene, or phenylboronic acid group. The great enhancement of the fluorescence of C1SP was due to a pi-pi stacking interaction, by which the bond rotation of C1SP was effectively suppressed. The results indicate that C1SP and structurally related hemicyanine dyes potentially become powerful fluorescent indicators for aromatic compounds through the pi-pi stacking interaction in water.


Assuntos
Ciclodextrinas/química , Fluorescência , Corantes Fluorescentes/química , Compostos de Piridínio/química , Estrutura Molecular
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