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1.
Drug Chem Toxicol ; 41(4): 492-500, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29156995

RESUMEN

We have conducted animal toxicity tests of chemicals for a chemical safety program implemented by the Ministry of Economy, Trade and Industry of Japan. Here we conducted a combined repeated-dose and reproductive/developmental toxicity screening test of benzene, 1,1'-oxybis-, tetrapropylene derivs. (BOTD). BOTD was administered to 9-week-old Crl:CD(SD) male and female rats by gavage at 0, 40, 200, or 1000 mg/kg/day. Males were treated for 42 days including mating period. Females were treated for 42-53 days through the premating, mating, pregnancy, and until Day 4 of lactation periods. Increases in prothrombin time and activated partial thromboplastin time values were observed only in males at 200 and 1000 mg/kg/day. Hypertrophy of centrilobular hepatocytes was observed with increased liver weight in both sexes at 200 and 1000 mg/kg/day, but there was no histologic evidence of hepatotoxicity. Diffuse hypertrophy of follicular cells in thyroid glands was observed in females at 200 mg/kg/day and in both sexes at 1000 mg/kg/day, with an increased blood cholesterol level in females at 1000 mg/kg/day. The conception index was decreased for females at 1000 mg/kg/day; and no abnormalities were detected in the reproductive indices of implantation, delivery, or pups' condition, although a slight increase in the pups' body weight was noted at birth. Our data indicate a no-observed-adverse-effect level of 40 mg/kg/day for repeated-dose toxicity on the basis of the prolongation of blood coagulating time, and of 200 mg/kg/day for reproductive/developmental toxicity on the basis of the decreased conception index.


Asunto(s)
Benceno/toxicidad , Reproducción/efectos de los fármacos , Animales , Coagulación Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Femenino , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley
2.
Drug Chem Toxicol ; 40(3): 344-358, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27790921

RESUMEN

We have carried out animal toxicity tests of chemicals for a chemical safety program implemented by the Ministry of Economy, Trade, and Industry of Japan. Here, we tested 1-tert-butoxy-4-chlorobenzene in a combined repeat-dose and developmental and reproductive toxicity test. The test chemical was administered daily by gavage to 9-week-old Crl:CD (SD) rats at doses of 0, 20, 100, and 500 mg/kg/d. Males were treated for 42 d beginning 14 d before mating. Females were treated from 14 d before mating to day 4 of lactation. Decreased spontaneous locomotion, decreased respiratory rate, and incomplete eyelid opening were observed at 500 mg/kg/d (both sexes), but resolved within 30 min of administration, suggesting central nervous system depression. No notable changes were observed in body weight, food consumption, functional battery tests, or blood test. Increased liver weight with centrilobular or diffuse hepatocyte hypertrophy was observed at 100 and 500 mg/kg/d (both sexes). There were no biochemical or histopathological changes related to hepatotoxicity. Increased kidney weight with basophilic tubules, tubule dilatation, and increased hyaline droplets were observed in males dosed at 100 and 500 mg/kg/d. Immunohistochemical staining indicated α2u-globulin nephropathy, a male rat-specific toxicity. Although kidney weight was also increased in females dosed at 500 mg/kg/d, it was not considered to be an adverse effect because there were no histopathological changes. Pup weights on postnatal day 0 were decreased at 500 mg/kg/d and still decreased on postnatal day 4. Our data indicated the no-observed-adverse-effect-level for repeated-dose and reproductive/developmental toxicity for 1-tert-butoxy-4-chlorobenzene was 100 mg/kg/d.


Asunto(s)
Clorobencenos/toxicidad , Exposición Materna/efectos adversos , Exposición Paterna/efectos adversos , Éteres Fenílicos/toxicidad , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Reproducción/efectos de los fármacos , Administración Oral , Animales , Animales Recién Nacidos , Peso Corporal/efectos de los fármacos , Clorobencenos/administración & dosificación , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Femenino , Masculino , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Especificidad de Órganos , Éteres Fenílicos/administración & dosificación , Embarazo , Ratas Sprague-Dawley , Pruebas de Toxicidad
3.
Drug Chem Toxicol ; 38(4): 361-74, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25367778

RESUMEN

4-Methoxy-2-nitroaniline (4M2NA) is widely used as an intermediate for the synthesis of dyes, pigments and other chemical compounds. Since 4M2NA has amino-group and nitro-group on the benzene ring, it was expected that it induced obvious hemolytic anemia. We conducted a combined repeated dose and reproductive/developmental toxicity screening test according to Organisation for Economic Co-operation and Development (OECD) Test Guideline No. 422 (OECD TG 422) to enrich the toxic information and ensure the safety of 4M2NA. 4M2NA was administered to Crl:CD(SD) male and female rats by gavage at 0, 12.5, 75 or 450 mg/kg/day for 42 to maximum of 54 days through pre-mating, mating, pregnancy and lactation periods. An extramedullary hematopoiesis and congestion in spleen, and higher reticulocyte ratio were noted in only females at 450 mg/kg/day without decreased anemic parameters in the hematological examination. Hypertrophy of centrilobular hepatocytes in both sexes was observed with increased relative liver weight at 450 mg/kg/day. Furthermore, the diffuse follicular cell hypertrophy of the thyroid was observed in females at 450 mg/kg/day. No abnormalities were detected in the reproductive indices of copulation, delivery or fetal viability. We concluded the no-observed-adverse-effect level (NOAEL) for repeated-dose toxicity was 75 mg/kg/day based on the trace evidences of hemolytic anemia, and the NOAEL for reproductive/developmental toxicity as 450 mg/kg/day based on no toxicological concerns for reproductive endpoints. The hemolytic anemia was much milder than expected. Thus, we discussed the reason of this much less hemolytic effect from the point of view of the structural characteristics of 4M2NA.


Asunto(s)
Anemia Hemolítica/inducido químicamente , Compuestos de Anilina/toxicidad , Reproducción/efectos de los fármacos , Compuestos de Anilina/administración & dosificación , Animales , Relación Dosis-Respuesta a Droga , Femenino , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Lactancia , Masculino , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas , Ratas Sprague-Dawley , Reticulocitos/efectos de los fármacos , Reticulocitos/metabolismo , Factores Sexuales , Bazo/efectos de los fármacos , Bazo/patología , Pruebas de Toxicidad
4.
Regul Toxicol Pharmacol ; 70(3): 711-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25444998

RESUMEN

We propose a category approach to assessing the testicular toxicity of chemicals with a similar structure to ethylene glycol methyl ether (EGME). Based on toxicity information for EGME and related chemicals and accompanied by adverse outcome pathway information on the testicular toxicity of EGME, this category was defined as chemicals that are metabolized to methoxy- or ethoxyacetic acid, a substance responsible for testicular toxicity. A Japanese chemical inventory was screened using the Hazard Evaluation Support System, which we have developed to support a category approach for predicting the repeated-dose toxicity of chemical substances. Quantitative metabolic information on the related chemicals was then considered, and seventeen chemicals were finally obtained from the inventory as a shortlist for the category. Available data in the literature shows that chemicals for which information is available on the metabolic formation of EGME, ethylene glycol ethyl ether, methoxy- or ethoxyacetic acid do in fact possess testicular toxicity, suggesting that testicular toxicity is a concern, due to metabolic activation, for the remaining chemicals. Our results clearly demonstrate practical utility of AOP-based category approach for predicting repeated-dose toxicity of chemicals.


Asunto(s)
Glicoles de Etileno/toxicidad , Testículo/efectos de los fármacos , Acetatos/metabolismo , Animales , Bases de Datos Factuales , Glicoles de Etileno/farmacocinética , Masculino , Ratones , Ratas , Medición de Riesgo/métodos
5.
Regul Toxicol Pharmacol ; 65(1): 108-14, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23137930

RESUMEN

The available toxicity information for boron was reevaluated and four appropriate toxicity studies were selected in order to derive a tolerable daily intake (TDI) using newly proposed uncertainty factors (UFs) presented in Hasegawa et al. (2010). No observed adverse effect levels (NOAELs) of 17.5 and 8.8 mgB/kg/day for the critical effect of testicular toxicity were found in 2-year rat and dog feeding studies. Also, the 95% lower confidence limit of the benchmark doses for 5% reduction of fetal body weight (BMDL(05)) was calculated as 44.9 and 10.3 mgB/kg/day in mouse and rat developmental toxicity studies, respectively. Measured values available for differences in boron clearance between rats and humans and variability in the glomerular filtration rate (GFR) in pregnant women were used to derive chemical specific UFs. For the remaining uncertainty, newly proposed default UFs, which were derived from the latest applicable information with a probabilistic approach, and their subdivided factors for toxicokinetic and toxicodynamic variability were applied. Finally, overall UFs were calculated as 68 for rat testicular toxicity, 40 for dog testicular toxicity, 247 for mouse developmental toxicity and 78 for rat developmental toxicity. It is concluded that 0.13 mgB/kg/day is the most appropriate TDI for boron, based on rat developmental toxicity.


Asunto(s)
Boro/toxicidad , Medición de Riesgo/métodos , Animales , Benchmarking , Boro/administración & dosificación , Boro/farmacocinética , Perros , Relación Dosis-Respuesta a Droga , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Ratones , Nivel sin Efectos Adversos Observados , Embarazo , Ratas , Especificidad de la Especie , Incertidumbre
6.
Regul Toxicol Pharmacol ; 65(2): 189-95, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23246603

RESUMEN

We tested a category approach to predict the hepatotoxic effects of repeated doses of allyl esters using a new database for repeated-dose toxicity. Based on information on hepatotoxic mechanism of allyl acetate, the category was defined as allyl esters that are hydrolyzed to allyl alcohol. Allyl alcohol is readily oxidized to acrolein in the liver, causing hepatotoxicity. Seventeen marketed allyl esters were obtained and grouped into category by identifying or predicting allyl alcohol formation. Allyl esters with a saturated straight alkyl carboxylic acid moiety (allyl acetate, hexanoate and heptanoate as tested species, and allyl butyrate, pentanoate, octanoate, nonanoate and decanoate as untested species) are likely similar in rate of ester hydrolysis, thereby defining subcategory 1. NOAEL and LOAEL for the hepatotoxic effects were estimated at 0.12 and 0.25 mmol/kg/d for the untested species, based on those of allyl acetate. The remaining nine allyl esters with other alkyl or aromatic carboxylic acid moieties were placed in subcategory 2: their hepatotoxicity levels were not predictable due to an unclear match between their degree of structural complexity and rate of hydrolysis. Our results demonstrate the usefulness of the category approach for predicting the hepatotoxicity of untested allyl esters with saturated straight alkyl chains.


Asunto(s)
Compuestos Alílicos/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Bases de Datos Factuales , Hígado/efectos de los fármacos , Compuestos Alílicos/química , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Relación Dosis-Respuesta a Droga , Ésteres , Predicción , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Humanos , Hígado/patología , Nivel sin Efectos Adversos Observados , Relación Estructura-Actividad
7.
Mol Genet Metab ; 102(1): 91-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20855224

RESUMEN

P-glycoprotein (P-gp), the product of the MDR1 gene, shows large interindividual variations in expression, which leads to differences in the pharmacokinetics of the substrate drugs. The functions of single nucleotide polymorphisms located in the nuclear receptor-responsive element of the 5'-flanking region in the human MDR1 gene were analyzed in order to clarify the mechanism underlying the interindividual variation in P-gp expression. Electrophoretic mobility shift assays revealed that the -7833C>T substitution in the nuclear receptor-responsive region of MDR1 decreases the binding affinities of four nuclear receptors to their responsive elements: vitamin D receptor (VDR), thyroid hormone receptor (TR), constitutive androstane receptor (CAR), and pregnane X receptor (PXR). A reporter gene assay revealed that the C-to-T substitution at -7833 also reduces the transcriptional activation of MDR1 by VDR, TRß, CAR, and PXR. However, another SNP (-1211T>C substitution), which results in the formation of a xenobiotic responsive element-like sequence and a hypoxia responsive element-like sequence, failed to affect the aryl hydrocarbon receptor-dependent and hypoxia-induced transcriptional activation of MDR1. Although the frequency of the -7833C>T substitution in MDR1 is relatively low, the SNP is crucial because it may alter the pharmacokinetics of P-gp substrates in a small subset of the population.


Asunto(s)
Región de Flanqueo 5'/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Polimorfismo de Nucleótido Simple , Subfamilia B de Transportador de Casetes de Unión a ATP , Secuencia de Bases , Receptor de Androstano Constitutivo , Ensayo de Cambio de Movilidad Electroforética , Genes Reporteros , Humanos , Datos de Secuencia Molecular , Polinucleótidos/metabolismo , Receptor X de Pregnano , Unión Proteica , Receptores de Calcitriol/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Receptores beta de Hormona Tiroidea/metabolismo , Transcripción Genética , Células Tumorales Cultivadas
8.
Drug Metab Dispos ; 38(12): 2100-4, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20847137

RESUMEN

CYP3A4, the major form of cytochrome P450 (P450) expressed in the adult human liver, is involved in the metabolism of approximately 50% of commonly prescribed drugs. Several genetic polymorphisms in CYP3A4 are known to affect its catalytic activity and to contribute in part to interindividual differences in the pharmacokinetics and pharmacodynamics of CYP3A4 substrate drugs. In this study, catalytic activities of the two alleles found in East Asians, CYP3A4*16 (T185S) and CYP3A4*18 (L293P), were assessed using the following seven substrates: midazolam, carbamazepine, atorvastatin, paclitaxel, docetaxel, irinotecan, and terfenadine. The holoprotein levels of CYP3A4.16 and CYP3A4.18 were significantly higher and lower, respectively, than that of CYP3A4.1 when expressed in Sf21 insect cell microsomes together with human NADPH-P450 reductase. CYP3A4.16 exhibited intrinsic clearances (V(max)/K(m)) that were lowered considerably (by 84-60%) for metabolism of midazolam, carbamazepine, atorvastatin, paclitaxel, and irinotecan compared with CYP3A4.1 due to increased K(m) with or without decreased V(max) values, whereas no apparent decrease in intrinsic clearance was observed for docetaxel. On the other hand, K(m) values for CYP3A4.18 were comparable to those for CYP3A4.1 for all substrates except terfenadine; but V(max) values were lower for midazolam, paclitaxel, docetaxel, and irinotecan, resulting in partially reduced intrinsic clearance values (by 34-52%). These results demonstrated that the impacts of both alleles on CYP3A4 catalytic activities depend on the substrates used. Thus, to evaluate the influences of both alleles on the pharmacokinetics of CYP3A4-metabolized drugs and their drug-drug interactions, substrate drug-dependent characteristics should be considered for each drug.


Asunto(s)
Biocatálisis , Citocromo P-450 CYP3A/genética , Alelos , Animales , Atorvastatina , Camptotecina/análogos & derivados , Camptotecina/metabolismo , Carbamazepina/metabolismo , Citocromo P-450 CYP3A/metabolismo , Docetaxel , Asia Oriental , Ácidos Heptanoicos/metabolismo , Humanos , Irinotecán , Midazolam/metabolismo , Modelos Moleculares , Paclitaxel/metabolismo , Pirroles/metabolismo , Spodoptera , Especificidad por Sustrato , Taxoides/metabolismo , Terfenadina/metabolismo
9.
Epilepsia ; 51(12): 2461-5, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21204807

RESUMEN

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but life-threatening severe cutaneous adverse reactions. Recently, strong associations of HLA-B*1502 with carbamazepine-induced SJS/TEN have been found in Han Chinese patients. These associations have been confirmed in several Asian populations, excluding Japanese. SJS patients carrying HLA-B*1508, HLA-B*1511, or HLA-B*1521, which are members of the HLA-B75 type along with HLA-B*1502, were detected in studies in India and Thailand. In the current study, we genotyped the HLA-B locus from 14 Japanese typical and atypical SJS/TEN patients in whom carbamazepine was considered to be involved in the onset of adverse reactions. Although there were no HLA-B*1502 carriers, four patients had HLA-B*1511. Our data suggest that HLA-B*1511, a member of HLA-B75, is a risk factor for carbamazepine-induced SJS/TEN in Japanese.


Asunto(s)
Pueblo Asiatico/genética , Carbamazepina/efectos adversos , Antígenos HLA-B/genética , Síndrome de Stevens-Johnson/genética , Adolescente , Adulto , Anciano , Carbamazepina/uso terapéutico , Niño , Familia , Femenino , Genotipo , Antígeno HLA-B15 , Humanos , India , Masculino , Persona de Mediana Edad , Farmacogenética , Factores de Riesgo , Tailandia
10.
Regul Toxicol Pharmacol ; 58(2): 237-42, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20561553

RESUMEN

We propose new uncertainty factors (UFs) and a new subdivision of default factors in chemical risk assessment using a probabilistic approach based on the latest applicable information. Rounded values of 150 for mice, 100 for hamsters and rats, and 40 for rabbits, monkeys and dogs for inter- and intra-species differences (UF(AH)) were derived from the probabilistic combination of two log-normal distributions. Further calculation of additional UFs when chronic data (UF(S)) or NOAEL (UF(L)) are lacking was conducted using available log-normal distribution information. The alternative UF(S) and UF(L) values of 4 are considered to be appropriate for both cases where data are lacking. The default contributions of inter-species difference (UF(A)) and intra-species difference (UF(H)) to the UF(AH) of 100 for hamsters and rats as an example are considered to be 25 and 4, respectively. The UF(A) of 25 was subdivided into 25(0.6) (i.e., 7.0) for pharmacokinetics (PK) (UF(A,PK)) and 25(0.4) (i.e., 3.6) for pharmacodynamics (PD) (UF(A,PD)), and the UF(H) of 4 was evenly subdivided into 4(0.5) (i.e., 2) (UF(H,PK) and UF(H,PD)), to account for chemical-specific difference data between humans and laboratory animals for PK and/or PD. These default UFs, which come from actual experimental data, may be more appropriate than previous default UFs to derive tolerable daily intake values.


Asunto(s)
Antineoplásicos/toxicidad , Modelos Estadísticos , Incertidumbre , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Cricetinae , Perros , Haplorrinos , Humanos , Ratones , Nivel sin Efectos Adversos Observados , Conejos , Ratas , Medición de Riesgo/métodos , Especificidad de la Especie
12.
Drug Metab Dispos ; 37(9): 1895-903, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19541829

RESUMEN

CYP2C9 is a polymorphic enzyme that metabolizes a number of clinically important drugs. In this study, catalytic activities of seven alleles found in Japanese individuals, CYP2C9*3 (I359L), *13 (L90P), *26 (T130R), *28 (Q214L), *30 (A477T), *33 (R132Q), and *34 (R335Q), were assessed using three substrates (diclofenac, losartan, and glimepiride). When expressed in a baculovirus-insect cell system, the holo and total (apo and holo) CYP2C9 protein expression levels were similar among the wild type (CYP2C9.1) and six variants except for CYP2C9.13. A large part of CYP2C9.13 was present in the apo form P420. Compared with CYP2C9.1, all variants except for CYP2C9.34 exhibited substrate-dependent changes in K(m), V(max), and intrinsic clearance (V(max)/K(m)). For diclofenac 4'-hydroxylation, the intrinsic clearance was decreased markedly (by >80%) in CYP2C9.13, CYP2C9.30, and CYP2C9.33 and variably (63-76%) in CYP2C9.3, CYP2C9.26, and CYP2C9.28 due to increased K(m) and/or decreased V(max) values. For losartan oxidation, CYP2C9.13 and CYP2C9.28 showed 2.5- and 1.8-fold higher K(m) values, respectively, and all variants except for CYP2C9.34 showed >77% lower V(max) and intrinsic clearance values. For glimepiride hydroxylation, the K(m) of CYP2C9.13 was increased 7-fold, and the V(max) values of all variants significantly decreased, resulting in reductions in the intrinsic clearance by >80% in CYP2C9.3, CYP2C9.13, CYP2C9.26, and CYP2C9.33 and by 56 to 75% in CYP2C9.28 and CYP2C9.30. These findings suggest the necessity for careful administration of losartan and glimepiride to patients bearing these six alleles.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Alelos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/metabolismo , Animales , Western Blotting , ADN Complementario/biosíntesis , ADN Complementario/genética , Diclofenaco/metabolismo , Variación Genética , Humanos , Hipoglucemiantes/metabolismo , Insectos , Japón , Cinética , Losartán/metabolismo , Microsomas/metabolismo , Ratas , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato , Compuestos de Sulfonilurea/metabolismo
13.
Artículo en Japonés | MEDLINE | ID: mdl-20306701

RESUMEN

Serious adverse events (SAEs) induced by drugs occur rarely, but the symptoms are very critical and generally not related to their pharmacological activities. Although SAEs should be avoided wherever possible, their occurrence is unpredictable at this time. In this article, we describe the clinical condition, figures on reported occurrence in Japan and studies on genetic markers related to serious cutaneous adverse reactions (SCARs), drug induced liver injury (DILI and rhabdomyolysis among SAEs. Then we introduce our last 3 years' approach of exploratory study on genetic markers for Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN), two of SCARs, useful for Japanese patients, including construction of a new case collection system, study methodology and progress. As the result at this moment, no Japanese SJS/TEN patients including 12 carbamazepine-related and 23 aromatic anti-epileptic agent-related ones carried HLA-B 1502 that was reported to have a strong association with carbamazepine-induced SJS/TEN in Han Chinese patients. On the other hand, 5 in 15 allopurinol-related SJS/TEN patients were found to have HLA-B 5801 that was detected as a genetic marker for allopurinol-induced SCARs in Han Chinese and Caucasians. Hereafter, we have a plan to begin the new exploratory studies on genetic markers for DILI and rhabdomyolysis, in addition to SJS/TEN patients.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Erupciones por Medicamentos/etiología , Erupciones por Medicamentos/genética , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Marcadores Genéticos , Antígenos HLA-B , Rabdomiólisis/etiología , Rabdomiólisis/genética , Síndrome de Stevens-Johnson/inducido químicamente , Síndrome de Stevens-Johnson/etiología , Síndrome de Stevens-Johnson/genética , Pueblo Asiatico , Humanos
14.
J Toxicol Pathol ; 22(2): 125-31, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22271985

RESUMEN

In this study, we investigated the sequential changes in the development of renal tubular cysts in newborn rats treated with p-cumylphenol (PCP). Fifteen animals per sex were treated orally with 300 mg/kg/day of PCP for up to 18 days from postnatal day (PND) 4 and were sacrificed on PNDs 8, 12, 19 and 22 and after a 7 day recovery period. On PNDs 8 and 12, slight dilatation of the collecting ducts was frequently observed in the medulla and slight papillary necrosis was also noted in some cases. These dilated collecting ducts were lined with slightly hyperplastic epithelial cells. On PNDs 19 and 22, multiple large cystic changes arising from the collecting ducts in the outer medulla were seen. These cystically dilated ducts were also lined with hyperplastic epithelial cells. During the dosing period, the labeling index of proliferating cell nuclear antigen in the collecting duct epithelium was higher in the PCP-treated group than in the control group at all time points. After a 7 day recovery period, the cystic change still remained, although the cell density was decreased and the epithelial cells became flattened. On the other hand, basophilic tubules with peritubular lymphoid cell infiltration were multifocally observed in the cortex. In conclusion, PCP induced multiple renal cysts that developed in the collecting ducts of the outer medulla in neonatal rats, and it is suggested that epithelial cell proliferation may play some roles in the induction of cystic lesions.

15.
J Rural Med ; 14(2): 165-175, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31788138

RESUMEN

Objectives: Increasing activity levels in older people is important for maintaining quality of life and ameliorating the risks of morbidity related to falls, depression, and dementia. This study aimed to clarify the seasonal variation effects on total energy expenditure, number of steps, time spent in low- and moderate- or high-intensity physical activities, and daily activities performed. Patients and Methods: This was a cross-sectional study of 22 community-dwelling older individuals (3 men, 19 women; mean age, 75.1 ± 7.3 years) living in three districts of Gero, Gifu, who participated in the Gero Salon Project hosted by the Social Welfare Councils. Evaluations were conducted in each season from September 2016 to August 2017. We used a uniaxial accelerometer, the Lifecorder device, which measures physical activity, and the Physical Activity Scale for the Elderly to evaluate activities of daily living. Data were analyzed using the multiple comparisons (Bonferroni correction) method. Results: Total energy expenditure and time spent in moderate- or high-intensity activities did not show seasonal variations. However, the lowest number of steps was taken during the winter, and the number of steps increased significantly from winter to spring. The time spent in low-intensity physical activities was significantly longer in the spring and summer than in the winter. There was no significant seasonal difference in total Physical Activity Scale for the Elderly score, leisure activities, domestic activities, or work-related activities. However, there was a significant difference between the summer and winter scores in "outdoor gardening," with the lowest score observed during the winter. Conclusions: With climate changes in the winter months, "outdoor gardening" becomes difficult, thus decreasing the number of steps taken. Therefore, it is necessary to identify other ways for older people to maintain physical activity during the winter season.

16.
Arch Biochem Biophys ; 474(1): 82-90, 2008 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-18395509

RESUMEN

P-glycoprotein, encoded by the MDR1 gene, is a drug efflux transporter that is expressed in various tissues and plays an important role in the absorption and elimination of many drugs and xenobiotics. Induction of the MDR1 gene affects drug disposition and the efficacy of drug treatment. In this study, we demonstrated that the thyroid hormone receptor (TR) induces MDR1 gene expression in a thyroid hormone (TH)-dependent manner. The 5'-upstream region of the human MDR1 gene was examined for the presence of TH-responsive elements. Luciferase-reporter gene assays revealed that the TH response region is located between -7.9 and -7.8kb upstream from the transcription start site of MDR1. The region contains two TH response clusters, one of which includes a direct repeat with a three-nucleotide spacer (DR3) and a four-nucleotide spacer DR4(I), and the other of which includes two DR4s (II and III). Mutation analyses indicated that every direct repeat has a unique contribution to the TH response. In particular, DR4(I) was shown to be the most important element. Chromatin immunoprecipitation assays revealed that TR and retinoid X receptor (RXR) bind to the TH response region, and gel mobility shift assays confirmed that one molecule of TR/RXR heterodimer binds to each of the clusters in this region, with preferential binding to the upstream one. We furthermore demonstrated that two molecules of TR/RXR could bind simultaneously to the TH response region. The order of binding affinity to the direct repeats was DR4(I)>DR4(II)>DR4(III) approximately DR3. Our results indicate that these two closely spaced TR/RXR-binding clusters are both required for the maximal induction of MDR1 gene expression mediated by TR.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Regulación de la Expresión Génica/fisiología , Receptores de Hormona Tiroidea/fisiología , Secuencia de Bases , Sitios de Unión , Línea Celular , Inmunoprecipitación de Cromatina , Cartilla de ADN , Dimerización , Humanos , Receptores de Hormona Tiroidea/metabolismo , Receptores X Retinoide/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
J Intensive Care ; 6: 7, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29435330

RESUMEN

BACKGROUND AND PURPOSE: The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 and published in the Journal of JSICM, [2017; Volume 24 (supplement 2)] 10.3918/jsicm.24S0001 and Journal of Japanese Association for Acute Medicine [2017; Volume 28, (supplement 1)] http://onlinelibrary.wiley.com/doi/10.1002/jja2.2017.28.issue-S1/issuetoc.This abridged English edition of the J-SSCG 2016 was produced with permission from the Japanese Association of Acute Medicine and the Japanese Society for Intensive Care Medicine. METHODS: Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ) and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (> 66.6%) majority vote of each of the 19 committee members. RESULTS: A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation, and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty-seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for five CQs. CONCLUSIONS: Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

18.
Acute Med Surg ; 5(1): 3-89, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29445505

RESUMEN

Background and Purpose: The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 in Japanese. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. Methods: Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ), and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (>66.6%) majority vote of each of the 19 committee members. Results: A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for 5 CQs. Conclusions: Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

19.
Drug Metab Pharmacokinet ; 22(2): 129-35, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17495421

RESUMEN

An ATP-binding cassette transporter, multidrug resistance-related protein 3 (MRP3), is encoded by the ABCC3 gene. The MRP3 protein is expressed in several tissues, and functions as an efflux transporter for conjugated as well as unconjugated substrates. In this study, the 31 ABCC3 exons and their flanking introns were comprehensively screened for genetic variations in 89 Japanese subjects. Forty-six genetic variations, including 21 novel ones, were found: 8 were located in the 5'-flanking region, 14 in the coding exons (8 synonymous and 6 nonsynonymous variations), and 24 in the introns. Of these 46 variations, five novel nonsynonymous variations, 2221C>T (Gln741Stop), 2395G>A (Val799Met), 2798_2799delAG (Gln933ArgfsX64), 3657C>A (Ser1219Arg), and 4217C>T (Thr1406Met), were found as heterozygous variations. The allele frequencies were 0.011 for Ser1219Arg and 0.006 for the other four variations. Gln741Stop induces a stop codon at codon 741. Gln933ArgfsX64 causes a frame-shift at codon 933, resulting in early termination at codon 997. Both variations result in loss of 6 transmembrane helices (from the 12th to 17th helices) in the C-terminus and all regions of nucleotide binding domain 2. Thus, both variant proteins are assumed to be inactive. These data provide fundamental and useful information for pharmacogenetic studies on MRP3-transported drugs in Japanese.


Asunto(s)
Pueblo Asiatico/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Polimorfismo de Nucleótido Simple , Adenina , Citosina , Análisis Mutacional de ADN , Exones , Frecuencia de los Genes , Genotipo , Guanina , Heterocigoto , Humanos , Intrones , Japón , Desequilibrio de Ligamiento , Reacción en Cadena de la Polimerasa , Timina
20.
Drug Metab Pharmacokinet ; 22(1): 48-60, 2007 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-17329911

RESUMEN

Multidrug resistance-related protein 1 (MRP1), an ATP-binding cassette transporter encoded by the ABCC1 gene, is expressed in many tissues, and functions as an efflux transporter for glutathione-, glucuronate- and sulfate-conjugates as well as unconjugated substrates. In this study, the 31 exons and their flanking introns of ABCC1 were comprehensively screened for genetic variations in 153 Japanese subjects to elucidate the linkage disequilibrium (LD) profiles and haplotype structures of ABCC1 that is necessary for pharmacogenetic studies of the substrate drugs. Eighty-six genetic variations including 31 novel ones were found: 1 in the 5'-flanking region, 1 in the 5'-untranslated region (UTR), 20 in the coding exons (9 synonymous and 11 nonsynonymous variations), 4 in the 3'-UTR, and 60 in the introns. Of these, eight novel nonsynonymous variations, 726G>T (Trp242Cys), 1199T>C (Ile400Thr), 1967G>C (Ser656Thr), 2530G>A (Gly844Ser), 3490G>A (Val1164Ile), 3550G>A (Glu1184Lys), 3901C>T (Arg1301Cys), and 4502A>G (Asp1501Gly), were detected with an allele frequency of 0.003. Based on the LD profiles, the analyzed regions of the gene were divided into five LD blocks (Blocks -1 and 1 to 4). The multiallelic repeat polymorphism in the 5'-UTR was defined as Block -1. For Blocks 1, 2, 3 and 4, 32, 23, 23 and 13 haplotypes were inferred, and 9, 7, 7 and 6 haplotypes commonly found on > or = 10 chromosomes accounted for > or = 91% of the inferred haplotypes in each block. Haplotype-tagging single nucleotide polymorphisms for each block were identified to capture the common haplotypes. This study would provide fundamental and useful information for the pharmacogenetic studies of MRP1-dependently effluxed drugs in Japanese.


Asunto(s)
Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Regiones no Traducidas 3'/genética , Regiones no Traducidas 5'/genética , ADN/genética , Diabetes Mellitus/genética , Exones/genética , Variación Genética , Haplotipos , Humanos , Intrones/genética , Japón , Desequilibrio de Ligamiento/genética , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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