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1.
J Toxicol Sci ; 49(5): 231-240, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38692910

RESUMO

Drug-induced convulsions are a major challenge to drug development because of the lack of reliable biomarkers. Using machine learning, our previous research indicated the potential use of an index derived from heart rate variability (HRV) analysis in non-human primates as a biomarker for convulsions induced by GABAA receptor antagonists. The present study aimed to explore the application of this methodology to other convulsants and evaluate its specificity by testing non-convulsants that affect the autonomic nervous system. Telemetry-implanted males were administered various convulsants (4-aminopyridine, bupropion, kainic acid, and ranolazine) at different doses. Electrocardiogram data gathered during the pre-dose period were employed as training data, and the convulsive potential was evaluated using HRV and multivariate statistical process control. Our findings show that the Q-statistic-derived convulsive index for 4-aminopyridine increased at doses lower than that of the convulsive dose. Increases were also observed for kainic acid and ranolazine at convulsive doses, whereas bupropion did not change the index up to the highest dose (1/3 of the convulsive dose). When the same analysis was applied to non-convulsants (atropine, atenolol, and clonidine), an increase in the index was noted. Thus, the index elevation appeared to correlate with or even predict alterations in autonomic nerve activity indices, implying that this method might be regarded as a sensitive index to fluctuations within the autonomic nervous system. Despite potential false positives, this methodology offers valuable insights into predicting drug-induced convulsions when the pharmacological profile is used to carefully choose a compound.


Assuntos
4-Aminopiridina , Frequência Cardíaca , Aprendizado de Máquina , Convulsões , Animais , Masculino , Convulsões/induzido quimicamente , Frequência Cardíaca/efeitos dos fármacos , 4-Aminopiridina/efeitos adversos , Ácido Caínico/toxicidade , Convulsivantes/toxicidade , Ranolazina , Bupropiona/toxicidade , Bupropiona/efeitos adversos , Eletrocardiografia/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiopatologia , Telemetria , Biomarcadores
2.
Endocr J ; 68(7): 791-805, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-33692246

RESUMO

Somatostatin analogs are recommended for pharmacotherapy of TSH-secreting pituitary adenoma (TSHoma). A multicenter clinical trial was conducted to evaluate the efficacy and safety of lanreotide autogel treatment for TSHoma. A total of 13 Japanese patients with TSHoma were enrolled from February to December 2018 and treated with lanreotide autogel 90 mg every 4 weeks, with dose adjustments to 60 mg or 120 mg. Analysis was performed on data from patients receiving preoperative treatment (n = 6) up to 24 weeks and from those receiving primary or postoperative treatment (n = 7) up to 52 weeks. The primary efficacy endpoints were serum concentrations of TSH, free triiodothyronine (FT3), and free thyroxine (FT4). The secondary efficacy endpoints were pituitary tumor size and clinical symptoms. The serum concentrations of TSH, FT3, and FT4 decreased with treatment, and euthyroid status was maintained until final assessment. FT4 at final assessment was within reference ranges in 10/13 patients. The median (interquartile range) percent change in pituitary tumor size from baseline at final assessment was -23.8% (-38.1, -19.8). The clinical symptoms were also improved. The patients receiving preoperative treatment did not develop perioperative thyroid storm. Regarding safety, adverse events were observed in 12/13 patients, but none discontinued treatment. The common adverse events were gastrointestinal disorders (12/13 patients) and administration site reactions (5/13 patients). Lanreotide autogel may be effective for controlling thyroid function and reducing the pituitary tumor size, and is tolerable in patients with TSHoma (Japic Clinical Trials Information; JapicCTI-173772).


Assuntos
Adenoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Peptídeos Cíclicos/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Somatostatina/análogos & derivados , Adenoma/sangue , Adenoma/cirurgia , Feminino , Humanos , Japão , Masculino , Terapia Neoadjuvante , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/cirurgia , Cuidados Pré-Operatórios , Somatostatina/uso terapêutico , Testes de Função Tireóidea , Tiroxina/sangue , Resultado do Tratamento , Tri-Iodotironina/sangue
3.
EMBO J ; 26(15): 3521-33, 2007 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-17627274

RESUMO

To cope with life-threatening high osmolarity, yeast activates the high-osmolarity glycerol (HOG) signaling pathway, whose core element is the Hog1 MAP kinase cascade. Activated Hog1 regulates the cell cycle, protein translation, and gene expression. Upstream of the HOG pathway are functionally redundant SLN1 and SHO1 signaling branches. However, neither the osmosensor nor the signal generator of the SHO1 branch has been clearly defined. Here, we show that the mucin-like transmembrane proteins Hkr1 and Msb2 are the potential osmosensors for the SHO1 branch. Hyperactive forms of Hkr1 and Msb2 can activate the HOG pathway only in the presence of Sho1, whereas a hyperactive Sho1 mutant activates the HOG pathway in the absence of both Hkr1 and Msb2, indicating that Hkr1 and Msb2 are the most upstream elements known so far in the SHO1 branch. Hkr1 and Msb2 individually form a complex with Sho1, and, upon high external osmolarity stress, appear to induce Sho1 to generate an intracellular signal. Furthermore, Msb2, but not Hkr1, can also generate an intracellular signal in a Sho1-independent manner.


Assuntos
Proteínas Ativadoras de GTPase/fisiologia , Proteínas de Membrana/fisiologia , Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana/genética , Microscopia de Fluorescência , Mutação , Pressão Osmótica , Proteínas de Saccharomyces cerevisiae/genética
4.
Zoolog Sci ; 24(1): 95-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17409722

RESUMO

Sex is determined by various transcription factors. Dmrt1, a gene that contains the DM domain (Doublesex/Mab-3 DNA-binding motif), is known to be one of the critical factors required for testicular development in vertebrates. Recently, other DM domain-containing genes (DMRT genes) were isolated in mice and fish. In mice, three of the seven known DMRT genes are expressed in the embryonic gonad. In amphibians, however, only Dmrt1 and Dmrt4 have been cloned. To clarify the role(s) of DMRT genes in sex determination in vertebrates, the molecular cloning of amphibian DMRT genes would be very helpful. In this study, we isolated Dmrt2, -3, and -5 from the frog Rana rugosa and analyzed by RT-PCR their expression during sex determination. The analysis revealed that all three genes are expressed in the developing gonad/mesonephros complex during sex determination with no dimorphism. The results suggest that Dmrt2, -3, and -5 may be involved in sexual development in R. rugosa and that they may function in both testicular and ovarian differentiation.


Assuntos
Ranidae/genética , Processos de Determinação Sexual , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Primers do DNA/genética , DNA Complementar/genética , Feminino , Componentes do Gene , Gônadas/metabolismo , Masculino , Dados de Sequência Molecular , Ranidae/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Fatores de Transcrição/genética
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