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1.
Regul Toxicol Pharmacol ; 122: 104919, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33753112

RESUMEN

The Standard for Exchange of Nonclinical Data (SEND) has been adopted by the US FDA, which has required pharmaceutical companies who are developing new drugs for the US market to implement SEND. The Japan Pharmaceutical Manufacturers Association (JPMA) SEND Taskforce Team responded to this situation by starting a project to better understand the contents of SEND datasets. The project focused on domains generally included in the SEND domains for single- and repeat-dose general toxicology studies, and surveyed what kind of information are populated in which domains and in what way. The qualitative analysis of the results indicated that variations exist based on whether or not an individual variable was populated and on how the variable was populated. The Taskforce Team recommends reducing variations not only in the SEND datasets but also in the descriptions in the study protocol and/or final study report. Reduction of such variations should lead to higher quality datasets with powerful and increased searchability so that accumulated SEND datasets should become more valuable. These efforts would provide regulatory agencies with easier review of SEND datasets, which contributes to efficient development of new drug candidates.


Asunto(s)
Investigación Biomédica/normas , Bases de Datos como Asunto/normas , Industria Farmacéutica/normas , Investigación Biomédica/organización & administración , Drogas en Investigación/normas , Humanos , Japón , Estados Unidos , United States Food and Drug Administration/normas
2.
Toxicol Pathol ; 47(2): 108-120, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30636562

RESUMEN

In nonclinical safety studies for new drug development, healthy animals have been commonly used. However, in some cases, the use of animal models of human disease is considered to be more favorable in evaluating risks in patients. To elucidate the current status of the use of animal models for nonclinical safety assessment, an internal questionnaire from the Japan Pharmaceutical Manufacturers Association and surveys (questionnaire period: August 27 to September 30, 2015) of both common technical documents and review reports of approved drugs (approval period: May 1999 to May 2017) disclosed by the Pharmaceutical and Medical Devices Agency were conducted. Although there were some concerns and limitations raised, the survey results revealed that animal models have been used in nonclinical safety assessment on a case-by-case basis and that nonclinical safety studies using animal models were included in the data packages of several approved drugs in Japan. The survey results also revealed that nonclinical safety studies using animal models have become more frequent in the past few years. In almost all cases, useful information, such as signs of toxicity under disease conditions and mechanisms of toxic change, was obtained from the results of nonclinical studies using animal models. Note: This is an opinion article submitted to the Toxicologic Pathology Forum. It represents the views of the author(s). It does not constitute an official position of the Society of Toxicologic Pathology, British Society of Toxicological Pathology, or European Society of Toxicologic Pathology, and the views expressed might not reflect the best practices recommended by these Societies. This article should not be construed to represent the policies, positions, or opinions of their respective organizations, employers, or regulatory agencies.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Industria Farmacéutica/métodos , Modelos Animales , Pruebas de Toxicidad/métodos , Animales , Humanos , Japón
3.
J Toxicol Sci ; 37(5): 1071-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23038015

RESUMEN

We previously reported that social isolation stimulated a stress response leading to increasing plasma corticosterone level and disruption of the hepatic lipid metabolism-related pathway, without changing body and organ weights, in mice after 4 weeks of social isolation stress, compared with the grouped-housing control (5 mice/cage). In this study, we evaluated the effects of social isolation stress for an extended period on physiologic changes in male C57BL/6J mice. Plasma corticosterone was reduced after 13 weeks, indicating mice might adapt to social isolation stress. However, body and visceral fat weights were significantly increased in combination with hepatic hypertrophy, and significant decreases in levels of triglyceride and adiponectin in plasma were observed. In conclusion, it is tempting to speculate that mice exposed to social isolation stress for 13 continuous weeks could be at an increased risk of overweight with hepatic hypertrophy. Our results also imply that physiological changes, at least fatty acid metabolism, under stress exposure might be an important factor when evaluating the chronic effects of environmental chemicals.


Asunto(s)
Hepatomegalia/etiología , Hígado/patología , Sobrepeso/etiología , Aislamiento Social , Estrés Psicológico/complicaciones , Animales , Hepatomegalia/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Tamaño de los Órganos/efectos de los fármacos
4.
Dalton Trans ; 40(40): 10643-57, 2011 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-21927723

RESUMEN

Photochromic dithienylethene (DTE) derivatives, M-DTE-M (M: M(η(5)-C(5)R(5))L(2); M = Fe, Ru; R = H, Me; L = CO, phosphine), with direct σ-bonded, redox-active organometallic attachments are prepared and their response to photo- and electro-chemical stimuli as well as wire-like and switching performance has been investigated. These properties turn out to be dependent on the metal and the auxiliary ligands. The DTE complexes with the MCp(CO)(2) and RuCp(CO)(PPh(3)) fragments undergo reversible photochemical ring-closing and -opening of the DTE moiety upon UV and visible-light irradiation, respectively, whereas the other FeCp(CO)(PPh(3)) and Fe(η(5)-C(5)R(5))(dppe) derivatives are virtually inert with respect to the photochemical ring closing process. Electrochemical analysis of the DTE complexes reveals that 2e-oxidation of the open isomer O also brings about the ring closure of the DTE moiety to afford the Fischer-carbene-type, dicationic closed derivatives C(2+) with the π-conjugated system different from that in the neutral ones C obtained photochemically. Subsequent reduction of C(2+) furnishes the neutral closed species C. Thus the ring closure is mediated not only by the conventional photochemical process but also by the sequential oxidation-reduction process, i.e. the organometallic DTE complexes are found to be dually photo- and electro-chromic. It is notable that the oxidative procedures are viable for the photochemically inert derivatives. Wire-like and switching performance has been evaluated on the basis of the comproportionation constant K(C) for the 1e-oxidized mixed valence monocationic species obtained by the electrochemical analysis and the switching factor SF (K(C)(C)/K(C)(O)), respectively. The K(C)(C) (7.5 × 10(4)) and SF values (5.4 × 10(3)) for phosphine-substituted derivatives are significantly large, as a result of the distinct π-conjugated systems of the DTE moieties involved in the O- (with cross-conjugation) and C-forms (fully conjugated). Compared to the previously reported acetylide-type complexes bridged by a DTE linker, (dppe)Cp*M-C≡C-DTE-C≡C-MCp*(dppe), both parameters have been significantly improved by factors of ~150. Time-dependent DFT analysis for the photochemical processes has revealed that the ring-closing process occurs not only via the ligand centered singlet excited state but also via the ligand centered triplet state resulting from energy transfer processes between the ligand- and metal-centered excited states and that this proposed mechanism can account for the photochemical reactivity of ruthenium complexes superior to that of the corresponding iron derivatives.


Asunto(s)
Complejos de Coordinación/química , Compuestos Organometálicos/química , Tiofenos/química , Técnicas Electroquímicas , Electrones , Hierro/química , Luz , Conformación Molecular , Oxidación-Reducción , Fosfinas/química , Fotólisis , Rutenio/química , Factores de Tiempo , Rayos Ultravioleta
5.
Risk Anal ; 30(12): 1817-32, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20626688

RESUMEN

The aim of this study was to evaluate the effects of implemented control measures to reduce illness induced by Vibrio parahaemolyticus (V. parahaemolyticus) in horse mackerel (Trachurus japonicus), seafood that is commonly consumed raw in Japan. On the basis of currently available experimental and survey data, we constructed a quantitative risk model of V. parahaemolyticus in horse mackerel from harvest to consumption. In particular, the following factors were evaluated: bacterial growth at all stages, effects of washing the fish body and storage water, and bacterial transfer from the fish surface, gills, and intestine to fillets during preparation. New parameters of the beta-Poisson dose-response model were determined from all human feeding trials, some of which have been used for risk assessment by the U.S. Food and Drug Administration (USFDA). The probability of illness caused by V. parahaemolyticus was estimated using both the USFDA dose-response parameters and our parameters for each selected pathway of scenario alternatives: washing whole fish at landing, storage in contaminated water, high temperature during transportation, and washing fish during preparation. The last scenario (washing fish during preparation) was the most effective for reducing the risk of illness by about a factor of 10 compared to no washing at this stage. Risk of illness increased by 50% by exposure to increased temperature during transportation, according to our assumptions of duration and temperature. The other two scenarios did not significantly affect risk. The choice of dose-response parameters was not critical for evaluation of control measures.


Asunto(s)
Perciformes/microbiología , Medición de Riesgo , Alimentos Marinos/microbiología , Vibrio parahaemolyticus/patogenicidad , Animales , Humanos , Japón , Vibrio parahaemolyticus/crecimiento & desarrollo , Vibrio parahaemolyticus/aislamiento & purificación
6.
Physiol Genomics ; 37(2): 79-87, 2009 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-19106182

RESUMEN

To elucidate the physiological responses to a social stressor, we exposed mice to an isolation stress and analyzed their hepatic gene expression profiles using a DNA microarray. Male BALB/c mice were exposed to isolation stress for 30 days, and then hepatic RNA was sampled and subjected to DNA microarray analysis. The isolation stress altered the expression of 420 genes (after considering the false discovery rate). Gene Ontology analysis of these differentially expressed genes indicated that the stress remarkably downregulated the lipid metabolism-related pathway through peroxisome proliferator-activated receptor-alpha, while the lipid biosynthesis pathway controlled by sterol regulatory element binding factor 1, Golgi vesicle transport, and secretory pathway-related genes were significantly upregulated. These results suggest that isolation for 30 days with a mild and consecutive social stress regulates the systems for lipid metabolism and also causes endoplasmic reticulum stress in mouse liver.


Asunto(s)
Perfilación de la Expresión Génica , Metabolismo de los Lípidos/genética , Hígado/metabolismo , Aislamiento Social/psicología , Estrés Psicológico/fisiopatología , Animales , Análisis por Conglomerados , Masculino , Ratones , Ratones Endogámicos BALB C , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
7.
Chem Commun (Camb) ; (44): 5812-4, 2008 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-19009090

RESUMEN

Organometallic dithienylethenes with the redox-active M(eta(5)-C(5)H(5))L(2)-type attachments (M = Fe, Ru; L = CO, PR(3)) exhibit bimodally stimuli-responsive, photo- and pseudo-electrochromic behavior with the remarkable switching factors [K(C)(closed)/K(C)(open)] up to 5.4 x 10(3).

8.
Biochem Biophys Res Commun ; 349(2): 775-80, 2006 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-16949032

RESUMEN

We investigated whether or not three kinds of social stress (isolation, crowding, and confrontation) increase urinary excretion of biopyrrins, oxidative metabolites of bilirubin, in mice. Male BALB/c mice (4 weeks old) were housed 5 per cage for 10 days. After acclimatization, mice were exposed to the above mentioned three kinds of psychosocial stress. Mouse blood and urine samples were collected after 2, 7, and 30 days of stress. Serum levels of corticosterone and urinary levels of biopyrrins were determined by EIA and ELISA, respectively. Adrenal hypertrophy, significant increases in serum concentration of corticosterone and in urinary excretion of biopyrrins were observed in mice exposed to these types of social stress for 7 days. These levels decreased after 30 days, though they were still rather high compared to the control group. These results suggested that social stress causes oxidative stress and that biopyrrins could be useful biomarkers of psychosocial stress.


Asunto(s)
Bilirrubina/metabolismo , Bilirrubina/orina , Oxígeno/química , Estrés Psicológico , Animales , Bilirrubina/química , Peso Corporal , Corticosterona/metabolismo , Corticosterona/orina , Técnicas para Inmunoenzimas , Masculino , Ratones , Ratones Endogámicos BALB C , Estrés Oxidativo , Oxígeno/metabolismo , Especies Reactivas de Oxígeno , Factores de Tiempo
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