Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Steroids ; 153: 108526, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669061

RESUMO

Nandrolone decanoate (ND) is one of the most commonly abused anabolic androgenic steroids compounds in the world owing to its ability to improve physical performance but its abuse is associated with several adverse effects. The current study was performed to evaluate the effect of recommended and overdose of nandrolone decanoate (ND) for short and long term on the alterations of biochemical markers related to kidney, liver, adrenal, thyroid gland functions and oxidant and antioxidant activities. Sixty male rats were randomly assigned into two major groups. The first was treated with ND for 6 weeks and the second was treated with same drug for 12 weeks. Each of these groups was further subdivided into three sub groups: 1-Control (untreated rats), 2- Rats intraperitoneally injected with ND 3 mg/kg weekly, 3- Rats intraperitoneally injected with ND 15 mg/kg weekly. Administration of high ND dose for either short or long term significantly elevated kidney function biomarkers, liver enzymes both in serum, cytosol and mitochondria, insignificantly increased thyroid function, significantly increased adrenal function while, decreased ACTH. Moreover, oxidative stress biomarkers were significantly upregulated associated with depression in antioxidants activities. Administration of high ND dose for either short or long term as well as the repeated use of recommended ND dose for long term proved to have harmful effects manifested in impairing the functions of kidneys, liver, thyroid and adrenal glands as well as oxidant antioxidant balance.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Anabolizantes/farmacologia , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Decanoato de Nandrolona/farmacologia , Glândula Tireoide/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Anabolizantes/administração & dosagem , Animais , Antioxidantes/metabolismo , Biomarcadores/análise , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Rim/metabolismo , Fígado/metabolismo , Masculino , Decanoato de Nandrolona/administração & dosagem , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Glândula Tireoide/metabolismo
2.
BMJ Open ; 8(5): e019273, 2018 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-29730618

RESUMO

OBJECTIVES: Aiming to validate the use of a single poststimulus sampling protocol for cosyntropin test short standard high-dose test (SST) in our institution, our primary objectives were (1) to determine the concordance between 30 and 60 min serum cortisol (SC) measurements during SST; and (2) to evaluate the diagnostic agreement between both sampling times when using classic or assay-specific and sex-specific SC cut-off values. The secondary objectives included (1) estimating the specificity and positive predictive value of 30 and 60 min sampling times while considering the suspected origin of adrenal insufficiency (AI); and (2) obtaining assay-specific cut-off values for SC after SST in a group of subjects with normal hypothalamic-pituitary-adrenal (HPA) axis. DESIGN AND SETTING: This is a retrospective chart review study conducted at a Spanish academic hospital from 2011 to 2015. PARTICIPANTS AND INTERVENTIONS: Two groups were evaluated: (1) a main study group including 370 patients in whom SC was measured at 30 and 60 min during SST; and (2) a confirmative group that included 150 women presenting with a normal HPA axis in whom SST was conducted to rule out late-onset congenital adrenal hyperplasia. Diagnostic agreement between both sampling times was assessed by considering both classic (500 nmol/L) and assay-specific SC cut-off concentrations. RESULTS: Diagnostic agreement between both sampling times was greater when applying sex-specific and assay-specific cut-off values instead of the classic cut-off values. For suspected primary AI, 30 min SC determination was enough to establish a diagnosis in over 95% of cases, without missing any necessary treatment. When central AI is suspected, 60 min SC measurement was more specific, establishing a diagnosis in over 97% of cases. CONCLUSIONS: Sex-specific and assay-specific SC cut-off values improve the diagnostic accuracy of SST. For primary disease, a subnormal SC response at 30 min is a reliable marker of adrenal dysfunction. On the contrary, when central AI is suspected, 60 min SC measurement improves the diagnostic accuracy of the test.


Assuntos
Testes de Função do Córtex Suprarrenal/métodos , Glândulas Suprarrenais/fisiopatologia , Insuficiência Adrenal/diagnóstico , Cosintropina/farmacologia , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/fisiologia , Insuficiência Adrenal/sangue , Insuficiência Adrenal/fisiopatologia , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Idoso , Feminino , Hospitais de Ensino , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/fisiologia , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Fatores Sexuais , Espanha
3.
Clin Biochem ; 56: 26-32, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29673814

RESUMO

BACKGROUND: Inhaled corticosteroids (ICS) are the recommended long-term control therapy for asthma in children. However, concern exists regarding potential adrenal suppression with chronic ICS use. Our pilot study reported that hair cortisol in children was 50% lower during ICS therapy than prior to therapy, suggestive of adrenal suppression. OBJECTIVE: To evaluate hair cortisol concentration (HCC) as a potential biomarker for possible adrenal suppression from ICS use in children with asthma. METHODS: A retrospective observational study was performed at asthma clinics in Vancouver, Winnipeg, and Toronto, Canada. Children (n = 586) were recruited from July 2012 to December 2014 inclusive of those without asthma, with asthma not using ICS, and with asthma using ICS. The most recent three-month HCC was measured by enzyme immunoassay and compared among the groups. Quantile regression analysis was performed to identify factors potentially affecting HCC. RESULTS: The median HCC was not significantly different among the children: No ICS (n = 47, 6.7 ng/g, interquartile range (IQR) 3.7-9.8 ng/g), ICS Treated (n = 360, 6.5 ng/g, IQR 3.8-14.3 ng/g), and Controls (n = 53, 5.8 ng/g, IQR 4.6-16.7 ng/g). 5.6% of the children using ICS had hair cortisol <2.0 ng/g compared to none in the control groups (P < .05, comparing ICS Treated (20/360) to all Controls combined (0/100)) and only half had been exposed to systemic corticosteroids. Age, sex, BMI, and intranasal corticosteroid use were significantly associated with HCC. CONCLUSIONS: Results suggest HCC may be a potential biomarker for adrenal suppression as a population of children using ICS with HCC < 2.0 ng/g was identified compared to none in the control groups. Further research is needed to determine if those children have or are at risk of adrenal suppression or insufficiency.


Assuntos
Corticosteroides/efeitos adversos , Glândulas Suprarrenais/efeitos dos fármacos , Insuficiência Adrenal/induzido quimicamente , Anti-Inflamatórios/efeitos adversos , Asma/tratamento farmacológico , Cabelo/metabolismo , Hidrocortisona/metabolismo , Administração Intranasal , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Glândulas Suprarrenais/metabolismo , Insuficiência Adrenal/epidemiologia , Insuficiência Adrenal/metabolismo , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Asma/metabolismo , Biomarcadores/metabolismo , Canadá/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Ambulatório Hospitalar , Projetos Piloto , Análise de Regressão , Estudos Retrospectivos , Risco
4.
Oncology ; 90(5): 248-54, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27070835

RESUMO

OBJECTIVE: We performed this prospective study to identify both the incidence of adrenal insufficiency (AI) and health-related quality of life (HRQOL) in advanced gastric cancer (AGC) patients who were treated with the S-1 plus cisplatin (SP) regimen as a first-line palliative chemotherapy. METHODS: We assessed adverse events (AEs) observed in 52 patients who received the SP regimen for AGC between January 2009 and June 2010 using the Common Toxicity Criteria Adverse Events (CTCAE) version 3.0. Adrenal function was assessed at baseline and 12 weeks after chemotherapy using the low-dose adrenocorticotropic hormone stimulation test. HRQOL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire version 3.0 (EORTC-QLQ C30). RESULTS: The incidence of AI was 30.8% (n = 16) and of AE observed 55% (n = 29) among 52 patients after 12 weeks of chemotherapy. Of 29 patients with AE, 34.4% (n = 10) were diagnosed with AI, and of 23 patients without AE, 26.1% (n = 6) were diagnosed with AI. CONCLUSION: The incidence of secondary AI in AGC patients was not rare and was not correlated with the presence of nonspecific AEs. Although patients diagnosed with AI did not show any related symptoms, they are at risk of potentially life-threatening consequences. Thus, the evaluation of AI could be suggested for patients who received chemotherapy.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Insuficiência Adrenal/sangue , Insuficiência Adrenal/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Qualidade de Vida , Neoplasias Gástricas/tratamento farmacológico , Insuficiência Adrenal/fisiopatologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Biomarcadores/sangue , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Intervalo Livre de Doença , Combinação de Medicamentos , Feminino , Gastrectomia , Nível de Saúde , Humanos , Hidrocortisona/sangue , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Ácido Oxônico/administração & dosagem , Ácido Oxônico/efeitos adversos , Projetos Piloto , Estudos Prospectivos , Neoplasias Gástricas/fisiopatologia , Tegafur/administração & dosagem , Tegafur/efeitos adversos , Resultado do Tratamento
5.
Methods Mol Biol ; 1366: 149-161, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26585133

RESUMO

In the field of protein biology, immunology-based techniques have been evolving for detection and quantification of protein levels, protein-protein interaction, and protein modifications in cells and tissues. The proximity ligation assay (PLA), a method of detection that combines immunologic and PCR-based approaches, was developed to overcome some of the drawbacks that are inherent to other detection methods. The PLA allows for very sensitive and discretely quantifiable measures of unmodified, native protein levels, and protein-protein interaction/modification complexes in situ in both fixed tissues and cultured cells. We describe herein the PLA method and its applicability to quantify the effects of estrogen on expression of angioregulatory factors, e.g., angiopoietin-1 (Ang-1) in the endometrium, vascular endothelial growth factor (VEGF) in the placenta, and melanocortin 2 receptor (MC2R)/accessory protein (MRAP) in the fetal adrenal of the nonhuman primate.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Endométrio/efeitos dos fármacos , Estrogênios/farmacologia , Placenta/efeitos dos fármacos , Mapeamento de Interação de Proteínas , Proteínas/metabolismo , Proteômica/métodos , Glândulas Suprarrenais/embriologia , Glândulas Suprarrenais/imunologia , Glândulas Suprarrenais/metabolismo , Angiopoietina-1/metabolismo , Animais , Anticorpos/imunologia , Anticorpos/metabolismo , Especificidade de Anticorpos , Endométrio/imunologia , Endométrio/metabolismo , Feminino , Imunofluorescência , Microscopia de Fluorescência , Oligonucleotídeos/metabolismo , Papio , Placenta/imunologia , Placenta/metabolismo , Reação em Cadeia da Polimerase , Gravidez , Ligação Proteica , Proteínas/imunologia , Receptor Tipo 2 de Melanocortina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fluxo de Trabalho
6.
Z Gastroenterol ; 47(7): 671-3, 2009 07.
Artigo em Inglês | MEDLINE | ID: mdl-19606410

RESUMO

Measurement of chromogranin A (CgA) level in blood can be used to monitor neuroendocrine tumours. However CgA level may also be elevated in several other endocrine and non-endocrine diseases. Here, we report on a patient with an incidental left-sided adrenal tumour and elevated CgA level. Adrenalectomy did not confirm clinically suspected diagnosis of pheochromocytoma. Postoperative follow-up was remarkable for a persistently elevated CgA level suspecting another neuroendocrine tumour which could not be detected despite extensive investigations. Finally, it was discovered that continuous proton-pump inhibitor administration for gastro-oesophageal reflux disease had caused a falsely elevated CgA level.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Cromogranina A/sangue , Inibidores da Bomba de Prótons/administração & dosagem , Humanos , Masculino , Taxa de Depuração Metabólica/efeitos dos fármacos , Pessoa de Meia-Idade
7.
Altern Med Rev ; 11(1): 40-6, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16597193

RESUMO

The impact of the synthetic glucocorticoid prednisone on adrenal steroid hormone production was examined using 24-hour urinary steroid hormone profiling. Five women, who were chronically taking low-dose prednisone, were tested, and the relevant literature was reviewed. As expected, adrenal glucocorticoid production, measured by urinary terminal cortisol and cortisone metabolites, was markedly suppressed compared to reference range values (p=0.03). Urinary cortisol and cortisone, reflecting circulating glucocorticoids, were decreased to a lesser extent than their terminal metabolites. Urinary dehydroepiandrosterone (DHEA) excretion was dramatically suppressed (p=0.03), while the downstream androgen metabolites androsterone and etiocholanolone were suppressed to a lesser extent. Aldosterone and tetrahydrocorticosterone production demonstrated modest suppression after prednisone administration, but allo-tetrahydrocorticosterone, which is highly sensitive to adrenocorticotropic hormone (ACTH) secretion, was suppressed to a greater extent. Prednisone administration results in a decrease in ACTH secretion by the anterior pituitary, suppressing synthesis of glucocorticoids, DHEA, and DHEA metabolites. Decreased glucocorticoid synthesis is adaptive, because prednisone is active at the glucocorticoid receptor, but suppression of DHEA synthesis is not mitigated by prednisone. DHEA is an important sex hormone precursor, neurosteroid, and endocrine and immune modulator; therefore, DHEA depletion may have significant adverse consequences in terms of sex hormone production, bone health, endocrine and immune system function, and neuropsychiatric status. Studies of DHEA replacement in patients taking prednisone for lupus demonstrate amelioration of some of these adverse effects.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Insuficiência Adrenal/induzido quimicamente , Anti-Inflamatórios/efeitos adversos , Prednisona/efeitos adversos , Glândulas Suprarrenais/metabolismo , Insuficiência Adrenal/urina , Adulto , Aldosterona/urina , Androsterona/urina , Anti-Inflamatórios/administração & dosagem , Cortisona/urina , Desidroepiandrosterona/urina , Etiocolanolona/urina , Feminino , Humanos , Hidrocortisona/urina , Pessoa de Meia-Idade , Prednisona/administração & dosagem
8.
Int J Toxicol ; 25(2): 119-26, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16597550

RESUMO

4'-Thio-beta-D-arabinofuranosylcytosine (OSI-7836) is a nucleoside analogue with structural similarity to gemcitabine and cytarabine (ara-C). Myelosuppression, reversible transaminase elevations, and flu-like symptoms are common side effects associated with human use of gemcitabine and ara-C. Fatigue is also associated with the use of gemcitabine and OSI-7836 in humans. To better understand the toxicity of OSI-7836, subchronic studies were conducted in dogs. OSI-7836 was administered on days 1 and 8 or on days 1, 2, and 3 of a 21-day dose regimen. These schedules attempted to match clinical trial dosing regimens. Routine toxicity study end points demonstrated that OSI-7836 was primarily cytotoxic to the gastrointestinal tract, bone marrow, and testes; the myelotoxicity was mild and reversible. Plasma pharmacokinetics were dose-linear with an elimination half-life of 2.2 h. Follow-up single dose experiments in dogs assessed drug effects on lymphocyte subpopulations and on adrenal and thyroid function. Populations of T and B cells were equally reduced following OSI-7836 administration. There were no adverse effects on thyroid function, but there were marked reductions in circulating cortisol and adrenocorticotropic hormone concentrations suggesting a centrally mediated impairment of the hypothalamic-pituitary-adrenal axis. These findings show a toxicological profile with OSI-7836 similar to other nucleoside analogues and suggest that the beagle is a model for studying one possible cause of OSI-7836-related fatigue, impaired function of the hypothalamic-pituitary-adrenal axis.


Assuntos
Antineoplásicos/toxicidade , Arabinonucleosídeos/toxicidade , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Hormônio Adrenocorticotrópico/sangue , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Arabinonucleosídeos/administração & dosagem , Arabinonucleosídeos/sangue , Arabinonucleosídeos/farmacocinética , Contagem de Células Sanguíneas , Cães , Avaliação Pré-Clínica de Medicamentos , Feminino , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Sistema Hipófise-Suprarrenal/metabolismo , Testículo/efeitos dos fármacos , Testículo/patologia , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Tiroxina/sangue
9.
Food Chem Toxicol ; 42(4): 625-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15019187

RESUMO

Increased human use of annatto (Bixa orellana L), a red yellow food colorant, demands generation of toxicity data. The toxic effects of annatto powder (bixin 27%) have been assessed following administration of a subacute regimen (4 weeks, 20 doses) in Wistar male and female rats. A full study with three dose levels was considered unnecessary since no sign of toxicity had been noted in a preliminary experiment with 1000 mg/kg body weight/day as was recommended by the OECD guideline. In this study, annatto administered by gavage at a dose level of 2000 mg/kg/day decreased male body weight gain, but had no effect on either food intake or food conversion efficiency. Haematological and plasma biochemical examination as well necropsy performed at the end of administration (29th day) and observation (43rd day) periods revealed no alterations related with annatto administration. Kidney apoptosis occurred in 20% treated female rats in restricted areas without proliferation or tubular segments modification. The precise nature of apoptosis was not investigated in the present study. These findings suggest that annatto was no toxic to the rat.


Assuntos
Corantes de Alimentos/toxicidade , Extratos Vegetais/toxicidade , Administração Oral , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/patologia , Animais , Apoptose/efeitos dos fármacos , Bixaceae , Carotenoides , Testes de Química Clínica , Feminino , Corantes de Alimentos/administração & dosagem , Testes Hematológicos , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Ratos , Ratos Wistar , Testes de Toxicidade
10.
Aquat Toxicol ; 67(1): 13-21, 2004 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-15019247

RESUMO

Rainbow trout (Oncorhynchus mykiss) and yellow perch (Perca flavescens) have a different sensitivity to cadmium (Cd) in vivo (trout < LC50 < perch). Metals and particularly Cd impair cortisol secretion by adrenocortical cells in both species. The purpose of the present study was to assess in vitro the effect of Cd on cortisol secretion by adrenocortical cells of trout and perch, to compare the sensitivity of adrenal steroidogenesis in these two teleosts. Adrenocortical cells were exposed to Cd for 60 min, then stimulated with ACTH, dbcAMP or with pregnenolone, a cortisol precursor. Cd inhibited ACTH-stimulated cortisol secretion in a dose-dependent manner in both fish species, however, the EC50s (concentration resulting in 50% inhibition of cortisol secretion) was significantly lower in trout (EC50 = 0.09 mM) than perch (EC50 = 0.26 mM). To test the specificity of Cd to act as an endocrine disrupter, the LC50 (concentration that kills 50% of the cells) was also evaluated to determine the LC50/EC50 ratio ( LC50/EC50(O.mykiss) = 175.6 > LC50/EC50(P.flavescens) = 37.7). Adrenocortical cells of trout were more sensitive than those of perch and Cd had a higher endocrine-disrupting potential and specificity in trout than in perch. However, in both species, Cd had the same effect on ACTH, dbcAMP and pregnenolone-stimulated cortisol secretion, with pregnenolone maintaining cortisol secretion until cell viability was impaired. These results confirm that for both species, Cd interferes in the signalling pathway of cortisol synthesis in a step prior to the pregnenolone formation. Data provided by the present study revealed important differences in vulnerability of adrenal steroidogenesis between rainbow trout and yellow perch.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Cádmio/toxicidade , Hidrocortisona/metabolismo , Oncorhynchus mykiss/metabolismo , Percas/metabolismo , Glândulas Suprarrenais/metabolismo , Hormônio Adrenocorticotrópico , Animais , AMP Cíclico , Concentração Inibidora 50 , Dose Letal Mediana , Pregnenolona , Transdução de Sinais/efeitos dos fármacos
12.
J Aerosol Med ; 16(1): 31-6, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12737682

RESUMO

Assessment of adrenal suppression via systemic cortisol levels provides an indirect measure of the lung delivery of inhaled corticosteroids. This randomized, placebo-controlled, double-blind, double-dummy crossover study compared urinary and plasma cortisol levels in healthy adult volunteers following single 1,000-microg doses of budesonide from two multiple dose dry powder inhalers (DPIs). Two new formulations of budesonide (lactose and PassCal) delivered from the Clickhaler were compared with Pulmicort from the Turbuhaler. An open dose (2,000 microg) of Pulmicort Turbuhaler was included to validate the experimental model. Overnight (22:00-07:00 h) and early morning (07:00-08:00 h) urine and 08:00 h plasma samples were collected after each treatment and cortisol levels analyzed by radioimmunoassay. Combined overnight and early morning urinary cortisol values for PassCal Clickhaler and Pulmicort Turbuhaler (1,000 microg) were statistically significantly lower than placebo (p < 0.05). The lactose budesonide Clickhaler showed a non-significant urinary cortisol reduction compared with placebo. Differences between the three 1,000-microg budesonide treatments were not significant. The Pulmicort Turbuhaler 2,000 microg showed significant urinary cortisol suppression compared with placebo. Plasma cortisol showed similar effects, with significance between the two Pulmicort doses. These results suggest that adrenal suppression can be used to assess the pulmonary bioavailability of different formulation.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Anti-Inflamatórios/administração & dosagem , Budesonida/administração & dosagem , Anti-Inflamatórios/farmacocinética , Disponibilidade Biológica , Budesonida/farmacocinética , Estudos Cross-Over , Método Duplo-Cego , Humanos , Hidrocortisona/sangue , Hidrocortisona/urina , Radioimunoensaio
14.
J Toxicol Sci ; 27(2): 107-22, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12058447

RESUMO

The water-soluble azole, 4-[1-[(3-methylaminoacetoxymethyl-pyridin-2-yl)-methyl-carbamoyloxy]- ethyl]-1-[(2R,3R)-3-[4-(4-cyano-phenyl)-thiazol-2-yl]-2- (2,5-difluoro-phenyl)-2-hydroxy-butyl]-1H-[1,2,4]triazol-4-ium chloride hydrochloride (hereinafter referred to as WSA), is a new water-soluble triazole anti-fungal compound. WSA is rapidly converted into its active metabolite after administration by either the intravenous or oral route. The clinical effects of WSA are expected to be consistent whether it is administered by injection (intravenous) or orally. To evaluate and compare the toxicities of WSA via oral and intravenous administration, repeated toxicity studies of WSA were conducted in cynomolgus monkeys (oral dosage levels: 0, 10, 30 and 90 mg/kg/day over a 4-week period; intravenous infusion dosage levels: 0, 10, 30 and 60 mg/kg/day over a 2-week period). In addition, a 2-week oral toxicity study of the active metabolite of WSA was conducted with similar dosages (0, 10, 30 and 90 mg/kg/day). From the results obtained from the evaluation, hepatotoxicity (liver) and endocrinological toxicity (adrenals) were the major toxicities, a finding which is comparable to other previously tested azole compounds. In the 4-week oral toxicity study, the lethal dose of WSA was determined to be 90 mg/kg. However, no animal mortality was observed during the 2-week intravenous continuous infusion study. The toxicokinetics (TK) profile of WSA at 10 and 30 mg/kg dosages illustrated a rapid, dose-dependent conversion of WSA to its active metabolite, and the plasma levels of Cmax and AUC were well correlated to their toxicities. However, at high dosages (60 and 90 mg/kg), WSA demonstrated high exposure beyond the dose-proportional manner. Overall, the results obtained indicate that maintaining an effective concentration and a non-toxic dosage level would be manageable by utilizing an initial intravenous continuous infusion followed by oral administration.


Assuntos
Antifúngicos/toxicidade , Azóis/toxicidade , Macaca fascicularis , Administração Oral , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/patologia , Animais , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Área Sob a Curva , Azóis/administração & dosagem , Azóis/farmacocinética , Relação Dose-Resposta a Droga , Feminino , Injeções Intravenosas , Fígado/efeitos dos fármacos , Fígado/patologia , Longevidade/efeitos dos fármacos , Masculino , Solubilidade , Testes de Toxicidade , Água
16.
Vopr Pitan ; 68(4): 45-8, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10509457

RESUMO

Characteristics of the product obtained by the authors from coriander cake, basic results of evaluation of its toxicological properties, basic stages of the experiment on white rats and its results are described. The conclusion about positive influence of the product on metabolism in white rats and perspectives of introduction of the new product from coriander cake as an additive for manufacture of food products is made.


Assuntos
Apiaceae/toxicidade , Aditivos Alimentares/toxicidade , Glândulas Suprarrenais/efeitos dos fármacos , Ração Animal , Animais , Análise Química do Sangue , Medula Óssea/química , Aditivos Alimentares/análise , Análise de Alimentos , Coração/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Masculino , Ratos , Baço/efeitos dos fármacos
17.
Hum Exp Toxicol ; 13(9): 581-97, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7986570

RESUMO

1. The methods used to evaluate the toxicological effects of PCBs in animals have been reviewed. 2. The data show that Toxic Equivalency Factors (TEFs) could be developed to assess the potential toxicity of PCB mixtures for certain specific target organ effects (such as the liver and immune system) but would be inappropriate for other effects (e.g. thyroid function and neurochemical effects). More data on a wider range of individual PCB congeners and a method for systematically balancing toxicodynamic and toxicokinetic data are required before the TEF approach can be fully evaluated. 3. With the exception of the teratogenic effects seen in mice and the anti-oestrogenic effects reported in in vitro studies, there are insufficient data on individual PCB congeners to evaluate the structure-activity relationships for the effects of PCBs on reproduction. The data also show that individual PCBs may have opposing effects on a particular aspect of reproduction (for example individual PCB congeners may have either oestrogenic or anti-oestrogenic effects). Studies with individual PCB congeners have shown both enhancement and antagonism of the teratogenic effects of 2, 3, 7, 8-tetrachloro dibenzo-p-dioxin (TCDD) in the mouse. It is not possible to use TEFs to evaluate the reproductive effects of PCBs. 4. The mechanism(s) responsible for the effects of PCBs on postnatal neurobehavioural development in rodents and monkeys have not been elucidated. At least two groups of PCBs which might be responsible for the observed effects have been identified in this review, one affecting the dopaminergic system and the other group affecting thyroid hormone levels. Considerably more research would be required before the TEF approach could be applied to the effects of PCBs on postnatal neurobehavioural development. This would include research on an appropriate animal model to determine whether the critical toxicological mechanism is mediated through the Ah receptor. 5. The reproductive toxicity of complex PCB mixtures such as those found in foods will depend on the identifies and relative proportions of individual PCB congeners in the mixture. It is not possible to give an accurate estimate of a NOAEL or LOAEL from the reproduction studies using commercial PCB mixtures which could be readily applied to the safety assessment of PCBs present as contaminants in food. 6. It is concluded that the data presented in this paper support the hypothesis that there is no satisfactory method derived from the available studies in laboratory animals for evaluating the potential risk of adverse effects on reproduction posed by contamination of foods with PCBs.


Assuntos
Bifenilos Policlorados/toxicidade , Reprodução/efeitos dos fármacos , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Estrogênios/metabolismo , Feminino , Contaminação de Alimentos , Humanos , Sistema Imunitário/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Pele/efeitos dos fármacos , Relação Estrutura-Atividade , Glândula Tireoide/efeitos dos fármacos
18.
Arch Toxicol ; 67(9): 622-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8311689

RESUMO

The effects of daily administration of phenobarbitone on the mitotic rates of several tissues were investigated by bromodeoxyuridine (BrdU) immunocytochemistry. Phenobarbitone (80 mg/kg per day) was dosed to AP Wistar male rats for up to 7 days and BrdU (10 mg/ml) was given by infusion at a rate of 10 microliters/h via subcutaneously implanted osmotic minipumps for 2 days prior to necropsy on days 1, 2, 3, 5 and 7. BrdU-labelled nuclei were visualised by peroxidase-antiperoxidase immunocytochemistry and counts of the numbers of labelled cells (labelling index, LI%) made from at least 1000 cells per tissue section(s). The LIs of several tissues (testis, adrenal cortex and medulla, kidney distal convoluted tubule and exocrine pancreas) showed no statistical difference by comparison with controls. Several tissues exhibited characteristic responses to phenobarbitone administration. Pituitary and endocrine pancreas LIs were decreased while those of thyroid, liver and kidney proximal convoluted tubule were increased. The pattern of LI increase was unique to each tissue with liver (median and lateral lobes) increased two-fold on day 3 and returning to control levels thereafter while kidney proximal tubule LI rose gradually with time and remained elevated on day 7. Thyroid LI on day 1 was almost double that of day 0 control and increased steadily thereafter. These data illustrate the varied responses of different tissues to phenobarbitone exposure, namely, depression and stimulation of mitosis. The causation of these functional changes is discussed in relation to direct and indirect effects on functional parameters, especially enzyme induction, alterations in hormonal and growth factor status and receptor regulation.


Assuntos
Bromodesoxiuridina , Fenobarbital/toxicidade , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Divisão Celular/efeitos dos fármacos , Imuno-Histoquímica , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Pâncreas/efeitos dos fármacos , Fenobarbital/farmacologia , Hipófise/efeitos dos fármacos , Ratos , Ratos Wistar , Testículo/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos
19.
Rev. Hosp. Clin. Fac. Med. Univ. Säo Paulo ; 47(2): 61-4, mar.-abr. 1992. tab
Artigo em Português | LILACS | ID: lil-120802

RESUMO

Hormonios da glandula supra-renal tem sido apontados como reguladores da homeostase extra-renal do potassio. O presente estudo avaliou o efeito do Florinef na modulacao dos mecanismos extra-renais de adaptacao ao potassio em ratos adrenalectomizados. Observou-se que os ratos tratados com Florinef apresentaram potassio plasmatico normal, provavelmente devido a entrada deste cation na celula por aumento da atividade da Na-K-ATPase.


Assuntos
Ratos , Animais , Masculino , Fludrocortisona/farmacocinética , Potássio/metabolismo , Glândulas Suprarrenais/efeitos dos fármacos , Adrenalectomia , Transporte Biológico Ativo , Homeostase/efeitos dos fármacos , Potássio/análise , Sódio/análise , Sódio/metabolismo
20.
Fertil Steril ; 57(3): 495-500, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1531463

RESUMO

OBJECTIVE: To examine the possible impact of abnormal adrenal steroidogenesis on the ovarian dysfunction seen in polycystic ovarian disease (PCOD). DESIGN: Prospective analysis of blood sampling monthly for 6 months, then three times weekly for 90 days. SETTING: Tertiary institutional outpatient care. PARTICIPANTS: Six anovulatory women with a diagnosis of PCOD. INTERVENTION: Six-month suppression with gonadotropin-releasing hormone agonist (GnRH-a) followed by suppression with dexamethasone (DEX) for 90 days. MAIN OUTCOME MEASURES: Serum levels of testosterone (T), androstenedione (A), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), cortisol, estradiol (E2), progesterone (P), follicle-stimulating hormone (FSH), luteinizing hormone (LH) and bioactive LH. RESULTS: Gonadotropin-releasing hormone agonist administration suppressed greater than 60% of the circulating levels of T and A, suggesting an ovarian origin. Minimal changes of DHEA, DHEAS, and cortisol were seen. With the addition of DEX, there was greater than 90% suppression of the total circulating A, T, DHEA, DHEAS, and cortisol, supporting the adrenal origin of the non-GnRH-a suppressible androgens. Excessive ovarian T and A secretion returned during the 90-day recovery study period in spite of rises of FSH concentrations that changed the ratio of FSH to LH in all subjects. Four of the six women failed to ovulate. In comparison of the women who did and did not ovulate during recovery, no differences in absolute levels or changes in concentrations of steroids or gonadotropins could be detected. CONCLUSIONS: Using sequential and simultaneous administration of GnRH-a and DEX, we were able to delineate the contributions of the ovaries and adrenals to the abnormal steroidogenesis seen in PCOD. Despite prolonged suppression of ovarian and then adrenal steroidogenesis, ovarian dysfunction, evidenced by abnormal androgen production, returned with cessation of agonist administration.


Assuntos
Glândulas Suprarrenais/metabolismo , Dexametasona/uso terapêutico , Hormônio Liberador de Gonadotropina/análogos & derivados , Síndrome do Ovário Policístico/tratamento farmacológico , Pamoato de Triptorrelina/análogos & derivados , Glândulas Suprarrenais/efeitos dos fármacos , Adulto , Androstenodiona/sangue , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Preparações de Ação Retardada , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/uso terapêutico , Humanos , Hidrocortisona/sangue , Hormônio Luteinizante/sangue , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/fisiopatologia , Progesterona/sangue , Estudos Prospectivos , Testosterona/sangue , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA