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1.
Pharmazie ; 70(2): 74-80, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25997245

RESUMO

This study was conducted to evaluate the pharmacokinetics of loxoprofen (LX) and its active metabolite (trans-OH form) after a single dermal application of LX gel (LX-G) to rats. In the skin at the treated site, generation of the trans-OH form was detected and both LX and the trans-OH form remained at high concentrations for 24 h after dermal application. Furthermore, both LX and the trans-OH form also remained in the skeletal muscle over 24 h after the single dermal application, while they eliminated rapidly after the single oral administration. The area under the curve up to the last measurable point (AUC(0-t)) for plasma concentrations of LX or the trans-OH form after dermal application of LX-G was less than 11% of that after oral administration of LX. In addition, C(max) and AUC(0-t) increased in a saturable manner while increasing the dose. Overall, these results demonstrated that the trans-OH form was generated at the treated site with the process of dermal absorption of LX and it remained at the target site for a long period with low systemic exposure compared to oral administration.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Fenilpropionatos/administração & dosagem , Fenilpropionatos/farmacocinética , Administração Oral , Administração Tópica , Animais , Géis , Meia-Vida , Injeções Intravenosas , Masculino , Pomadas , Ratos , Ratos Wistar , Absorção Cutânea , Distribuição Tecidual
2.
Braz J Med Biol Res ; 43(11): 1127-34, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21049245

RESUMO

Bone mass loss is a major complication of chronic cholestatic liver disease (CCD). However, the long-term impact of CCD on bone mass acquisition is unknown. We longitudinally assessed bone mineral density (BMD) and factors involved in bone remodeling in 9 children and adolescents with CCD Child-Pugh A (5 boys/4 girls) and in 13 controls (6 boys/7 girls). The groups were evaluated twice, at baseline (T0) and after 3 years (T1), when osteocalcin, deoxypyridinoline, 25-hydroxyvitamin-D, parathyroid hormone, insulin-like growth factor-I (IGF-I), and BMD (L1-L4, proximal femur and total body) were determined. Serum levels of receptor activator for nuclear factor kB ligand (RANKL) and osteoprotegerin were measured only at T1. Lumbar spine BMD was reanalyzed twice: after adjustment for bone age and to compensate for the height factor. Volumetric density was also estimated mathematically in L2-L4. The BMD of L1-L4 was lower in the CCD group (Z-score at T0: control = -1.2 ± 0.8 vs CCD = -2.2 ± 1.4, P < 0.05; T1: control = -0.7 ± 0.8 vs CCD = -2.1 ± 1.1, P < 0.05). Osteocalcin and deoxypyridinoline were similar for the two groups. The CCD group presented lower IGF-I (Z-score at T1: control = 1.4 ± 2.8 vs CCD = -1.5 ± 1.0, P < 0.05) and RANKL (control = 0.465 ± 0.275 vs CCD = 0.195 ± 0.250 pM, P < 0.05) than control. Children with compensated CCD Child-Pugh A showed early impairment of bone acquisition, with the impact being more severe in an initial phase and then tapering in a slowly progressive way. Reduction in endocrine IGF-I has a crucial role in this process.


Assuntos
Doenças Ósseas Metabólicas/etiologia , Colestase Intra-Hepática/complicações , Adolescente , Densidade Óssea , Doenças Ósseas Metabólicas/sangue , Remodelação Óssea , Estudos de Casos e Controles , Criança , Colestase Intra-Hepática/sangue , Doença Crônica , Feminino , Humanos , Estudos Longitudinais , Masculino , Osteoprotegerina/sangue , Ligante RANK/sangue
3.
Braz. j. med. biol. res ; 43(11): 1127-1134, Nov. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-564127

RESUMO

Bone mass loss is a major complication of chronic cholestatic liver disease (CCD). However, the long-term impact of CCD on bone mass acquisition is unknown. We longitudinally assessed bone mineral density (BMD) and factors involved in bone remodeling in 9 children and adolescents with CCD Child-Pugh A (5 boys/4 girls) and in 13 controls (6 boys/7 girls). The groups were evaluated twice, at baseline (T0) and after 3 years (T1), when osteocalcin, deoxypyridinoline, 25-hydroxyvitamin-D, parathyroid hormone, insulin-like growth factor-I (IGF-I), and BMD (L1-L4, proximal femur and total body) were determined. Serum levels of receptor activator for nuclear factor kB ligand (RANKL) and osteoprotegerin were measured only at T1. Lumbar spine BMD was reanalyzed twice: after adjustment for bone age and to compensate for the height factor. Volumetric density was also estimated mathematically in L2-L4. The BMD of L1-L4 was lower in the CCD group (Z-score at T0: control = -1.2 ± 0.8 vs CCD = -2.2 ± 1.4, P < 0.05; T1: control = -0.7 ± 0.8 vs CCD = -2.1 ± 1.1, P < 0.05). Osteocalcin and deoxypyridinoline were similar for the two groups. The CCD group presented lower IGF-I (Z-score at T1: control = 1.4 ± 2.8 vs CCD = -1.5 ± 1.0, P < 0.05) and RANKL (control = 0.465 ± 0.275 vs CCD = 0.195 ± 0.250 pM, P < 0.05) than control. Children with compensated CCD Child-Pugh A showed early impairment of bone acquisition, with the impact being more severe in an initial phase and then tapering in a slowly progressive way. Reduction in endocrine IGF-I has a crucial role in this process.


Assuntos
Adolescente , Criança , Feminino , Humanos , Masculino , Doenças Ósseas Metabólicas/etiologia , Colestase Intra-Hepática/complicações , Densidade Óssea , Remodelação Óssea , Doenças Ósseas Metabólicas/sangue , Estudos de Casos e Controles , Doença Crônica , Colestase Intra-Hepática/sangue , Estudos Longitudinais , Osteoprotegerina/sangue , Ligante RANK/sangue
4.
J Pediatr Gastroenterol Nutr ; 31(4): 391-4, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11045836

RESUMO

BACKGROUND: Celiac disease (CD) is a permanent gluten intolerance disorder characterized by malabsorption, intestinal mucosa villus atrophy, and crypt hyperplasia. Clinical and histologic features improve in persons consuming a gluten free diet. The pathogenesis of CD involves environmental, genetic, and immunologic factors. METHODS: The frequencies of human leukocyte antigen (HLA) class II alleles were evaluated in white Brazilian patients who had CD and compared with those observed in healthy individuals from the same geographical area (Ribeirão Preto, São Paulo) and of similar ethnic background. Twenty-five patients with CD, 11 females and 14 males, and 91 control individuals were studied. The HLA class II alleles were typed using amplified DNA hybridized with sequence-specific primers. Statistical analysis was performed using the two-tailed Fisher exact test. The relative risk (RR), etiologic fraction (EF), and preventive fraction (PF) were also estimated. The EF represents the attributable risk for the development of CD at the population level, whereas PF represents the protective risk. RESULTS: The frequency of the HLA-DRB1*03, HLA-DRB1*07, and HLA-DQB1*02 alleles was significantly increased in patients. The RR conferred by these alleles was 5.35, 7.15, and 10.6, respectively, and the EF was 48.7%, 44.7%, and 76%, respectively. The frequency of HLA-DQB1*06 alleles was significantly decreased in CD patients, conferring an RR of 0.08 and a PF of 48%. CONCLUSIONS: The results show that HLA-DRB1*03, HLA-DRB1*07, and HLA-DQB1*02 alleles conferred susceptibility to CD in Brazilian patients. In contrast, HLADQB1*06 alleles conferred protection against development of the disease.


Assuntos
Alelos , Doença Celíaca/genética , Antígenos HLA-D/genética , População Branca/genética , Brasil , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genes Recessivos , Predisposição Genética para Doença , Genótipo , Antígenos HLA-D/imunologia , Humanos , Masculino
5.
Biol Pharm Bull ; 23(5): 669-71, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10823688

RESUMO

Azole antifungal agents (azoles) have inhibitory effects on the cytochrome P450. However, the effect of azoles on conjugative metabolism has not been given much attention. Lorazepam (LZP), a benzodiazepine sedative agent, is known to be metabolized by uridine 5'-diphosphate (UDP)-glucuronyltransferase. Herein we report investigation of the effect of azoles on the enzyme-kinetics of glucuronidation of lorazepam using rabbit liver microsomes in vitro. The Km and Vmax for LZP glucuronidation were determined to be 0.26+/-0.08 mM and 1.25+/-0.21 nmol/min/mg protein, respectively, when evaluated in the presence of a detergent 3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate (CHAPS) (0.8 mg/mg protein). Azoles fluconazole, miconazole, and ketoconazole competitively inhibited the glucuronidation of LZP, with Ki values of 7.17+/-4.78 mM, 0.17+/-0.08 mM, and 0.092+/-0.026 mM, respectively. These results are comparable to the previously reported Ki values of azoles with zidovudine (AZT) glucuronidation (1.4, 0.18, and 0.08 mM for fluconazole, miconazole, and ketoconazole, respectively) [Sampol et al., Br. J. Clin. Pharmacol., 40, 83-86, 1995]. Therefore, in order to avoid possible side effects of LZP, the concomitant administration of LZP and azoles should be carefully evaluated.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Lorazepam/metabolismo , Microssomos Hepáticos/metabolismo , Animais , Ansiolíticos/metabolismo , Ligação Competitiva , Detergentes/farmacologia , Fluconazol/farmacologia , Ácido Glucurônico/metabolismo , Técnicas In Vitro , Cetoconazol/farmacologia , Cinética , Masculino , Miconazol/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Coelhos , Uridina Difosfato Ácido Glucurônico/farmacologia
6.
Am J Trop Med Hyg ; 61(4): 642-7, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10548302

RESUMO

Capillaria hepatica is a helminth that may cause an extremely rare condition of parasitic hepatitis. Only 29 cases have been published, 2 of them in Brazil. We report here 3 cases of children in Brazil with massive hepatic capillariasis who presented the characteristic triad of this type of infection, i.e., persistent fever, hepatomegaly, and eosinophilia. The diagnosis was made by liver biopsy. All children responded well after treatment with thiabendazole (case 1), albendazole (case 3), and albendazole in combination with a corticoid (case 2). Case 1 has been followed-up for 24 years, an event not previously reported in the literature.


Assuntos
Capillaria/patogenicidade , Infecções por Enoplida/diagnóstico , Hepatite/diagnóstico , Hepatopatias Parasitárias/diagnóstico , Fígado/parasitologia , Albendazol/uso terapêutico , Animais , Anti-Helmínticos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Biópsia , Brasil , Pré-Escolar , Infecções por Enoplida/tratamento farmacológico , Eosinofilia , Feminino , Febre , Seguimentos , Hepatite/tratamento farmacológico , Hepatite/parasitologia , Hepatomegalia , Humanos , Lactente , Fígado/patologia , Hepatopatias Parasitárias/tratamento farmacológico , Masculino , Contagem de Ovos de Parasitas , Prednisona/uso terapêutico , Tiabendazol/uso terapêutico
8.
Arq Gastroenterol ; 34(1): 55-61, 1997.
Artigo em Português | MEDLINE | ID: mdl-9458961

RESUMO

Persistent diarrhea, a condition highly prevalent in developing countries, causes different morphological and functional alterations of the mucosa of the small intestine, including increased permeability to different test molecules. In the present study we investigate for the first time the intestinal permeability to 51Cr-EDTA of Brazilian children with persistent diarrhea. The test of 51Cr-EDTA absorption was performed in 13 control children and in 14 children with persistent diarrhea by offering 50 microCi of the test substance by the oral route, with later detection of radioactivity excreted in 24-hour urine. There was a statistically significant difference between the control group (median = 1.26; range = 0.20-3.31%) and the group with persistent diarrhea (median = 4.68; range = 1.40-10.29%). Using the minimum and maximum values detected in the control group as the normal reference standard for the test of urinary 51Cr-EDTA absorption, we observed that 61.5% of the patients with persistent diarrhea showed altered results. Among the patients with persistent diarrhea, 51Cr-EDTA excretion was significantly higher in the group fed a protein hydrolysate diet and/or total parenteral nutrition than in the group that did not receive this diet. In four patients with persistent diarrhea, the test was performed after clinical recovery, with a fall in the excretion levels in all cases. On the basis of these data, we may conclude that: 1) in persistent diarrhea there must be alteration of intestinal permeability that might permit an increased entry of local alimentary antigens, with subsequent sensitization and allergic enteropathy, contributing to the perpetuation of the diarrhea, malabsorption and malnutrition cycle; 2) the 51Cr-EDTA test may be useful as an indicator of severity in persistent diarrhea; 3) alteration of intestinal permeability is a secondary phenomenon in persistent diarrhea, with normalization occurring after reconstruction of the intestinal barrier.


Assuntos
Diarreia Infantil/metabolismo , Ácido Edético/farmacocinética , Intestino Delgado/metabolismo , Absorção , Criança , Pré-Escolar , Radioisótopos de Cromo/farmacocinética , Radioisótopos de Cromo/urina , Doença Crônica , Feminino , Humanos , Lactente , Masculino , Permeabilidade
9.
Arq Gastroenterol ; 33(3): 179-81, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9201332

RESUMO

Two children with Budd-Chiari syndrome were successfully submitted to thrombolytic therapy. This study suggests that streptokinase is safe and effective in the treatment of this syndrome and should be considered as primary treatment in case of early diagnosed acute disease in view of the poor prognosis and the aggressiveness of surgical treatment currently available.


Assuntos
Síndrome de Budd-Chiari/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Estreptoquinase/uso terapêutico , Terapia Trombolítica , Criança , Seguimentos , Humanos , Masculino
10.
J Pediatr (Rio J) ; 72(3): 159-63, 1996.
Artigo em Português | MEDLINE | ID: mdl-14688949

RESUMO

Cytomegalovirus infection is symptomatic in only 10% of cases. The most frequent findings are cholestasis and hepatosplenomegaly. Ten patients who presented neonatal cholestasis associated with cytomegalovirus infection were studied. The majority had elevation of serum aminotransferases and mild abnormality of hepatic function. The histopathologic findings were: normal, giant cell hepatitis, bile duct proliferation (confused with extrahepatic biliary atresia) and ductopenia. The clinical course of the patients varied from disappearance of the symptoms (2 cases) to death (2 cases). Because of the possibility of confusing the histologic findings with extrahepatic biliary atresia, the etiology of neonatal cholestasis, including cytomegalovirus infection, should be determined as soon as possible.

12.
Arq Gastroenterol ; 32(3): 146-51, 1995.
Artigo em Português | MEDLINE | ID: mdl-8728790

RESUMO

We studied 20 children with a clinical picture and laboratory study suggestive of hepatic glycogenosis. The age of the beginning of symptoms varied from birth to 24 months and the age at the diagnosis varied from 2 to 81 months. Hepatomegaly was found in all patients, diarrhea in 65% (13/26), "doll-face" in 55% (11/20) and convulsions in 50% (10/20). Nutritional evaluation showed more height deficiency than weight deficiency. Laboratory tests showed elevation of hepatic transaminases (12/19), hypercolesterolemia (8/14), hyperuricemia (6/17) and hypoglycemia (6/20). Liver function was not compromised in most of the cases. The results of glucagon tolerance test were variable. The histoenzymology study performed in 15 patients revealed the following results: Type VI (liver phosphorylase deficiency) in seven, Type I (glucose-6-phosphatase deficiency) in two, Type IV (brancher enzyme) in one and no conclusion could be drawn in five patients. The finding of hypoglycemia in few cases of this study can be justified by the few number of glycogenosis Type I, probably due to the fact that this type is the most easily diagnosed, with less necessity of referring them to specialized centers.


Assuntos
Doença de Depósito de Glicogênio/diagnóstico , Estatura , Peso Corporal , Pré-Escolar , Feminino , Doença de Depósito de Glicogênio/fisiopatologia , Humanos , Lactente , Masculino , Estado Nutricional , Estudos Retrospectivos , Transaminases/sangue
13.
Arq Gastroenterol ; 32(2): 85-90, 1995.
Artigo em Português | MEDLINE | ID: mdl-8540806

RESUMO

We evaluated 51 tests of 99mTc-DISIDA excretion by the biliary tree in patients with neonatal cholestasis. The aim of the present study was to verify the value of this test in the differentiation of this syndrome, correlating it to the clinical and laboratory data. The case studied were divided into two groups: extrahepatic biliary atresia, 26 patients (50.9%) and no-extrahepatic biliary atresia, 25 patients (49.1%). Analyzing the results, we concluded that this test had 96% sensitivity, 56% specificity, 69% positive predictive value, 93% negative predictive value and 76.5% accuracy. The accuracy of this test was only lower than that of hepatic biopsy. We conclude that the hepatobiliary scintigraphy was very useful in the definition of extrahepatic biliary atresia, with less value in the group of neonatal hepatitis, perhaps due to the delayed referral of the patients, short time of the scintigraphy study or factors related to the etiology of cholestasis itself.


Assuntos
Colestase Extra-Hepática/diagnóstico por imagem , Iminoácidos/metabolismo , Icterícia Neonatal/etiologia , Compostos de Organotecnécio/metabolismo , Colestase Extra-Hepática/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Icterícia Neonatal/diagnóstico , Masculino , Cintilografia , Estudos Retrospectivos , Disofenina Tecnécio Tc 99m
14.
Biol Pharm Bull ; 18(2): 256-61, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7742794

RESUMO

Using primary cultured mouse hepatocytes, in vitro study was performed to discuss the effect of Cr(III) and several other trace metals, Cr(VI), Mn(II), Zn(II), Co(II), Cu(II), Ni(II), and Ga(III) on acute liver damage induced by CCl4 exposure. 1) The LDH activity 60 min after CCl4 exposure increased dose-dependently with CCl4 concentrations in all of the trace metal pretreatment groups, except for the Cr(VI) pretreatment group, which showed a significant protective effect even after 30 min of CCl4 exposure. 2) LDH leakage was not observed 10 min after CCl4 exposure at 3 or 5 mM, while lipid peroxidation was increased dose-dependently with CCl4 concentrations in all groups except the Cr(VI) pretreatment group, in which the production of peroxidated lipid was significantly inhibited. 3) Similarly to the pretreatment with Cr(VI), LDH leakage 30 min after exposure to 5 mM CCl4 was inhibited by pretreatment with such antioxidants as N,N'-diphenyl-p-phenylenediamine or DL-alpha-tocopherol. 4) The Cr(VI) uptake was about 50% of the added amount, whereas the Cr(III) uptake was only 5% of the added amount. 5) 90% or more of the intracellular chromium was reduced to Cr(III) 10 min after Cr(VI) treatment. The results suggested that the in vitro protective effect of pretreatment with Cr(VI) was due to a rapid reduction of Cr(VI) to Cr(III), and the radical scavenger-like effect of the produced Cr(III) was the same effect as in vivo Cr(III); it therefore suggests that Cr(III) contributes to protective effect on CCl4-induced hepatotoxicity.


Assuntos
Tetracloreto de Carbono/toxicidade , Cromo/toxicidade , Fígado/efeitos dos fármacos , Oligoelementos/toxicidade , Animais , Antioxidantes/farmacologia , Tetracloreto de Carbono/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromo/metabolismo , Peroxidação de Lipídeos , Fígado/citologia , Fígado/metabolismo , Masculino , Camundongos
15.
Arq Gastroenterol ; 32(1): 8-14, 1995.
Artigo em Português | MEDLINE | ID: mdl-7575185

RESUMO

We studied yogurts and industrialized curdled milk in three different storage times, as well as homemade and Syrian curdled milk and cheeses. Lactose content (gm%) and beta-galactosidase activity were determined in these products. Lactose content was elevated in yogurts and curdled milk with a lactose reduction of about 22% compared to the lactose of cow milk, with a mean and standard desviation (M +/- SD) of 3.81 +/- 0.47 gm%. In the cheeses lactose content was low, between 1.91 and 0.03 g%. beta-galactosidase activity was present in yogurts and curdled milk, with values between 0.58 and 3.61 U in time I and M +/- SD of 0.15 +/- 0.23 U. A significant decrease of beta-galactasidase activity was observed during the storage time. By analyzing and comparing these findings with the literature, we conclude that the products studied, by their low content of lactose (cheeses and yakult) or by the presence of beta-galactasidase activity (yogurts and curdled milk at time I) probably would be tolerated by most hipolactasic persons.


Assuntos
Queijo/análise , Laticínios/análise , Galactose/análise , Lactose/análise , Iogurte/análise , beta-Galactosidase/metabolismo , Brasil , Fermentação , Manipulação de Alimentos , Fatores de Tempo
16.
Arq Gastroenterol ; 31(1): 30-8, 1994.
Artigo em Português | MEDLINE | ID: mdl-8085953

RESUMO

The authors present an updated review of intestinal permeability with emphasis on permeability pathways, test substances and the techniques most commonly employed for the study and quantification of this process. They also point out certain pediatric conditions associated with abnormal intestinal permeability.


Assuntos
Absorção Intestinal , Enteropatias/fisiopatologia , Mucosa Intestinal/fisiopatologia , Criança , Dissacarídeos/farmacocinética , Ácido Edético/farmacocinética , Epitélio/fisiopatologia , Feminino , Humanos , Masculino , Monossacarídeos/farmacocinética , Polietilenoglicóis/farmacocinética
17.
Carcinogenesis ; 13(3): 391-3, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1547528

RESUMO

Dimethylarsinic acid (DMAA) administration induced the preferential increase of the heterochromatic area forming the inside of the interphase nucleus. A histopathological study of the lung and liver in mice after DMAA administration was carried out by transmission electron microscopy. Ultrastructural alterations in the endothelial nuclei of the alveolar wall were observed 12-48 h after administration. Heterochromatin tended to collect in a dense, compact mass lining the inner walls of the nucleus. A significant increase in heterochromatin induced by DMAA administration was observed by morphometric analysis. However, no substantial differences appeared in the sinusoidal endothelium of the liver. This study suggests that the much greater induction of morphological alterations, such as increased heterochromatin, in lung endothelial nuclei than in the liver might explain the high risk of lung cancer by arsenics, and that there may be a close relationship between heterochromatin alteration and DNA damages.


Assuntos
Ácido Cacodílico/toxicidade , Endotélio Vascular/efeitos dos fármacos , Heterocromatina/efeitos dos fármacos , Pulmão/irrigação sanguínea , Animais , Endotélio Vascular/ultraestrutura , Fígado/irrigação sanguínea , Fígado/ultraestrutura , Pulmão/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microscopia Eletrônica
18.
Arch Environ Contam Toxicol ; 21(1): 146-51, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1898113

RESUMO

Freshwater and seawater acclimated (FWA and SWA) killifish (Oryzias latipes) were exposed to pentachlorophenol (PCP) for 3-10 days. Uptake and clearance rates of FWA and SWA killifish were determined. The estimated bioaccumulation factors (BCF) of PCP for FWA and SWA killifish were 1680 and 370, respectively. The smaller uptake rate and faster clearance rate resulted in the lower BCF for SWA killifish. Fresh- and seawater killifish excreted the PCP metabolites, the glucuronide and sulfate conjugates of PCP; the major metabolite of freshwater killifish was PCP sulfate; for seawater acclimated fish, it was PCP glucuronide. The greater excretion of PCP glucuronide by seawater killifish may be responsible for the rapid elimination of PCP. PCP accumulation in killifish decreased with higher pH levels in both freshwater and seawater environments, but these differences were less than the effect of salinity. The results indicate that salinity can affect the accumulation and elimination of environmental pollutants in killifish.


Assuntos
Peixes Listrados/metabolismo , Pentaclorofenol/farmacocinética , Poluentes Químicos da Água/farmacocinética , Animais , Água Doce , Vesícula Biliar/metabolismo , Concentração de Íons de Hidrogênio , Pentaclorofenol/metabolismo , Água do Mar , Distribuição Tecidual
19.
Toxicol Appl Pharmacol ; 108(2): 205-13, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2017750

RESUMO

Oral administration of dimethylarsinic acid (DMAA), a major metabolite of inorganic arsenics, induces DNA damage in the mouse and rat lung due to both active oxygens and dimethylarsenic peroxyl radical produced in the metabolism of DMAA. Our paper describes the cellular response to DMAA in the mouse lung. In male ICR mice given a single po dose (1500 mg/kg) of DMAA-Na, the activities of mitochondrial superoxide dismutase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase significantly increased at 6 hr or longer after dosing, while cytosolic superoxide dismutase and catalase did not. With regard to cellular sulfhydryls after DMAA dosing, levels of reduced glutathione and nonprotein sulfhydryl decreased, while mixed disulfides significantly increased. Further, NADPH markedly decreased at 6-9 hr after DMAA dosing. These cellular variations suggest that the mouse pulmonary cell produced active oxygens, i.e., superoxide anion radical, hydrogen peroxide, and subsequent radicals in the metabolism of DMAA and that these and also the dimethylarsenic peroxyl radical were responsible for pulmonary DNA damage.


Assuntos
Arsênio/metabolismo , Ácido Cacodílico/toxicidade , Pulmão/efeitos dos fármacos , Administração Oral , Animais , Ácido Cacodílico/administração & dosagem , Catalase/metabolismo , Dano ao DNA , Glucosefosfato Desidrogenase/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Pulmão/citologia , Pulmão/enzimologia , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , NADP/metabolismo , Oxirredução , Superóxido Dismutase/metabolismo
20.
Biochem Biophys Res Commun ; 168(1): 58-64, 1990 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-2158319

RESUMO

To reveal the mechanisms of previously reported lung-specific DNA strand scissions in murine after oral administration of dimethylarsinic acid (DMAA), a main metabolite of inorganic arsenics in mammals, the ultimate substance causing DNA lesion was investigated using dimethylarsine which was a further metabolite of DMAA. The alkaline elution assay using 3H-labeled DNA showed that a major portion of the strand breaks was not suppressed by SOD and catalase, suggesting an ultimate substance other than active oxygen participated in the DNA damage. By ESR analysis, a radical estimated to be (CH3)2AsOO. was detected as a reaction product of dimethylarsine and molecular oxygen. This peroxyl radical, rather than active oxygen, was assumed to play a major role in DNA damage.


Assuntos
Intoxicação por Arsênico , Arsenicais , Dano ao DNA , DNA/efeitos dos fármacos , Fenômenos Químicos , Química , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Humanos , Técnicas In Vitro , Células L , Oxigênio , Superóxidos
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