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2.
Pharmaceuticals (Basel) ; 16(7)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37513906

RESUMO

Recent media reports commented about a possible issue of the misuse of antidiabetics related to molecules promoted as a weight-loss treatment in non-obese people. We evaluated here available pharmacovigilance misuse/abuse signals related to semaglutide, a glucagon-like peptide-1 (GLP-1) analogue, in comparison to other GLP-1 receptor agonists (albiglutide, dulaglutide, exenatide, liraglutide, lixisenatide, and tirzepatide) and the phentermine-topiramate combination. To acheieve that aim, we analyzed the Food and Drug Administration's FDA Adverse Events Reporting System (FAERS) dataset, performing a descriptive analysis of adverse event reports (AERs) and calculating related pharmacovigilance measures, including the reporting odds ratio (ROR) and the proportional reporting ratio (PRR). During January 2018-December 2022, a total of 31,542 AERs involving the selected molecules were submitted to FAERS; most involved dulaglutide (n = 11,858; 37.6%) and semaglutide (n = 8249; 26.1%). In comparing semaglutide vs. the remaining molecules, the respective PRR values of the AERs 'drug abuse', 'drug withdrawal syndrome', 'prescription drug used without a prescription', and 'intentional product use issue' were 4.05, 4.05, 3.60, and 1.80 (all < 0.01). The same comparisons of semaglutide vs. the phentermine-topiramate combination were not associated with any significant differences. To the best of our knowledge, this is the first study documenting the misuse/abuse potential of semaglutide in comparison with other GLP1 analogues and the phentermine-topiramate combination. The current findings will need to be confirmed by further empirical investigations to fully understand the safety profile of those molecules.

3.
BMC Anesthesiol ; 18(1): 96, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-30053804

RESUMO

BACKGROUND: Several hypnotic drugs have been previously identified as modulators of food intake, but exact mechanisms remain unknown. Feeding behavior implicates several neuronal populations in the hypothalamic arcuate nucleus including orexigenic neuropeptide Y and anorexigenic pro-opiomelanocortin producing neurons. The aim of this study was to investigate in mice the impact of different hypnotic drugs on food consumption and neuropeptide Y or pro-opiomelanocortine mRNA expression level in the hypothalamic arcuate nucleus. METHODS: Saline control, isoflurane, thiopental, midazolam or propofol were administered to C57Bl/6 mice. Feeding behavior was evaluated during 6 h. In situ hybridization of neuropeptide Y and pro-opiomelanocortine mRNAs in the hypothalamus brain region was also performed. Data were analyzed by Kruskal Wallis test and analysis of variance (p < 0.05). RESULTS: Midazolam, thiopental and propofol induced feeding behavior. Midazolam and thiopental increased neuropeptide Y mRNA level (respectively by 106 and 125%, p < 0.001) compared with control. Propofol and midazolam decreased pro-opiomelanocortine mRNA level by 31% (p < 0,01) compared with control. Isoflurane increased pro-opiomelanocortine mRNA level by 40% compared with control. CONCLUSION: In our murine model, most hypnotics induced food consumption. The hypnotic-induced regulation of neuropeptide Y and pro-opiomelanocortine hypothalamic peptides is associated with this finding. Our data suggest that administration of some hypnotic drugs may affect hypothalamic peptide precursor and neuropeptide expression and concomittantly modulate food intake. Thus, this questions the choice of anesthetics for better care management of patients undergoing major surgery or at risk of undernutrition.


Assuntos
Anestésicos/farmacologia , Núcleo Arqueado do Hipotálamo/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Neuropeptídeo Y/biossíntese , Pró-Opiomelanocortina/biossíntese , Animais , Masculino , Camundongos
4.
Rep Prog Phys ; 79(4): 046901, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27007555

RESUMO

Collisionless shocks, that is shocks mediated by electromagnetic processes, are customary in space physics and in astrophysics. They are to be found in a great variety of objects and environments: magnetospheric and heliospheric shocks, supernova remnants, pulsar winds and their nebulæ, active galactic nuclei, gamma-ray bursts and clusters of galaxies shock waves. Collisionless shock microphysics enters at different stages of shock formation, shock dynamics and particle energization and/or acceleration. It turns out that the shock phenomenon is a multi-scale non-linear problem in time and space. It is complexified by the impact due to high-energy cosmic rays in astrophysical environments. This review adresses the physics of shock formation, shock dynamics and particle acceleration based on a close examination of available multi-wavelength or in situ observations, analytical and numerical developments. A particular emphasis is made on the different instabilities triggered during the shock formation and in association with particle acceleration processes with regards to the properties of the background upstream medium. It appears that among the most important parameters the background magnetic field through the magnetization and its obliquity is the dominant one. The shock velocity that can reach relativistic speeds has also a strong impact over the development of the micro-instabilities and the fate of particle acceleration. Recent developments of laboratory shock experiments has started to bring some new insights in the physics of space plasma and astrophysical shock waves. A special section is dedicated to new laser plasma experiments probing shock physics.

5.
Pharmacogenomics J ; 15(1): 13-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24980785

RESUMO

It is not yet known whether healthy individuals and patients with a chronic disease have similar attitudes towards pharmacogenomics. Thus we conducted a survey of 175 healthy volunteers, 175 heart failure (HF) patients and 100 heart transplant recipients to compare their opinions on this subject. Most participants (>90%) stated that they would accept pharmacogenomic testing and expressed high hopes regarding its potential applications. Overall, interest for pharmacogenomics was shared equally among the three groups. In contrast, after adjusting for age, gender, education and income, healthy individuals were more likely to voice concerns about potential employment (P=0.008 vs HF, odds ratio (OR)=2.93, confidence interval (CI)=1.33-6.47; P=0.010 vs Transplant, OR=2.46, CI=1.24-4.90) and insurance discrimination (P=0.001 vs HF, OR=5.58, CI=2.01-15.48; P<0.001 vs Transplant, OR=4.98, CI=2.03-12.21) and were possibly more worried by confidentiality issues. These findings highlight the need for strict legislation and proper educational strategies directed at the general population to facilitate the clinical implementation of pharmacogenomics.


Assuntos
Cultura , Insuficiência Cardíaca/psicologia , Transplante de Coração/psicologia , Esperança , Farmacogenética , Transplantados/psicologia , Adulto , Idoso , Estudos Transversais , Feminino , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Farmacogenética/tendências
6.
Int J Toxicol ; 31(5): 454-66, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22914890

RESUMO

Exposure to environmental contaminants induces the activation of cytochrome P450s (CYP) which lead to the hydroxylation of contaminants and endogenous hormones such as estrogens. The hydroxylation of estrogens forms catecholestrogens (CEs), one of them being the mutagenic 4-hydroxyestradiol-17ß (4-OH-E2). Catecholestrogens are transformed by catechol-o-methyltransferases (COMTs) into nonreactive methoxyestrogens. To investigate the hepatic metabolism of estradiol-17ß in female offspring at postnatal day (PND) 21, pregnant rats were dosed daily from gestation day 1 until PND 21 with 2 dose levels of organochlorine pesticides (OCPs; 0.019 or 1.9 mg/kg per d), methylmercury (MeHg; 0.02 or 2 mg/kg per d), polychlorinated biphenyls (PCBs; 0.011 or 1.1 mg/kg per d), or a mixture (M; 0.05 or 5 mg/kg per d) including all 3 groups of chemicals. Concentrations of organochlorines in the mixture M were based on their proportions in serum of the Canadian Arctic population. The messenger RNA (mRNA) expressions of CYP and COMT were analyzed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). High-performance thin layer chromatography and phosphor imaging were used to measure the transformation of (14)C substrates into estrogen metabolites. The low-dose treatments or the MeHg groups had no effect. The high-dose OCP, PCB, and M group increased the production of 2-OH-E2 and 6α-OH-E2, while only the PCB and M groups increased the 2-OH-CE/methoxyestrogen ratio. In all groups, the cytosolic COMT activity exceeded the microsomal production rate of 4-OH-E2. Although the M treatment included the PCB and OCP mixtures, it did not modify the estrogen metabolism more than did the PCB mixture alone. This endocrine disruption information contributes to our understanding of chemical interactions in the toxicology of chemical mixtures.


Assuntos
Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Estradiol/metabolismo , Hidrocarbonetos Clorados/toxicidade , Compostos de Metilmercúrio/toxicidade , Praguicidas/toxicidade , Animais , Catecol O-Metiltransferase/genética , Sistema Enzimático do Citocromo P-450/genética , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Troca Materno-Fetal , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Sprague-Dawley
7.
Water Res ; 46(20): 6857-67, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22196044

RESUMO

Many authors have observed the influence of the settling velocity distribution on the sedimentation process in retention tanks. However, the pollutants' behaviour in such tanks is not well characterized, especially with respect to their settling velocity distribution. This paper presents a phenomenological modelling study dealing with the way by which the settling velocity distribution of particles in combined sewage changes between entering and leaving an off-line retention tank. The work starts from a previously published model (Lessard and Beck, 1991) which is first implemented in a wastewater management modelling software, to be then tested with full-scale field data for the first time. Next, its performance is improved by integrating the particle settling velocity distribution and adding a description of the resuspension due to pumping for emptying the tank. Finally, the potential of the improved model is demonstrated by comparing the results for one more rain event.


Assuntos
Material Particulado , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água , Simulação por Computador , Modelos Teóricos , Fatores de Tempo
8.
Water Sci Technol ; 64(9): 1898-905, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22020485

RESUMO

Theoretical studies have shown that discharges from retention tanks could have a negative impact on the WWTP's (Wastewater Treatment Plant) effluent. Characterization of such discharges is necessary to better understand these impacts. This study aims at: (1) characterizing water quality during emptying of a tank; and (2) characterizing the temporal variation of settling velocities of the waters released to the WWTP. Two full-scale sampling campaigns (18 rain events) have been realized in Quebec City and laboratory analyses have shown a wide variability of total suspended solids (TSS) and Chemical Oxygen Demand (COD) concentrations in the water released from the tank. Suspended solids seem to settle quickly because they are only found in large amounts during the first 15 min of pumping to the WWTP. These solids are hypothesized to come from the pumping in which solids remained after a previous event. When these solids are evacuated, low TSS containing waters are pumped from the retention tank. A second concentration peak occurs at the end of the emptying period when the tank is cleaned with wash water. Finally, settling velocity studies allowed characterizing combined sewer wastewaters by separating three main fractions of pollutants which correspond to the beginning, middle and end of emptying. In most cases, it is noticed that particle settling velocities increase as the pollutant load increases.


Assuntos
Esgotos/análise , Eliminação de Resíduos Líquidos , Purificação da Água/instrumentação , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , Fracionamento Químico , Cidades , Geografia , Quebeque , Chuva , Qualidade da Água
9.
J Mol Endocrinol ; 44(5): 295-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20219854

RESUMO

In the central nervous system of mammals, the gene encoding diazepam-binding inhibitor (DBI) is exclusively expressed in glial cells. Previous studies have shown that central administration of a DBI processing product, the octadecaneuropeptide ODN, causes a marked inhibition of food consumption in rodents. Paradoxically, however, the effect of food restriction on DBI gene expression has never been investigated. Here, we show that in mice, acute fasting dramatically reduces DBI mRNA levels in the hypothalamus and the ependyma bordering the third and lateral ventricles. I.p. injection of insulin, but not of leptin, selectively stimulated DBI expression in the lateral ventricle area. These data support the notion that glial cells, through the production of endozepines, may relay peripheral signals to neurons involved in the central regulation of energy homeostasis.


Assuntos
Inibidor da Ligação a Diazepam/metabolismo , Jejum , Neuroglia/metabolismo , Neuropeptídeos/metabolismo , Fragmentos de Peptídeos/metabolismo , Animais , Regulação para Baixo , Epêndima/metabolismo , Hipotálamo/metabolismo , Injeções Intraperitoneais , Insulina/administração & dosagem , Ventrículos Laterais/metabolismo , Leptina/administração & dosagem , Masculino , Camundongos , Neuropeptídeos/genética , Fragmentos de Peptídeos/genética , Ligação Proteica , Terceiro Ventrículo/metabolismo , Transcrição Gênica
10.
Transplant Proc ; 41(8): 3337-41, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19857745

RESUMO

Induction with rabbit antithymocyte immunoglobulins (RATG) for cardiac transplantation allows reduction of calcineurin inhibitor and reduces the incidence of acute rejection episodes (ARE). We compared induction with RATG combined with either cyclosporine (CsA) or tacrolimus (FK) in regard to the number of ARE in the first year after transplantation. We transplanted 111 patients from 2000 to 2008 including 61 who received CsA-RATG, and 19, FK-RATG. At 3 months and 1 year the CsA group displayed 3.29 +/- 1.66 and 7.44 +/- 2.45 ARE per patient of grade at least 1R respectively. The FK group showed 3.21 +/- 1.71 and 8.13 +/- 2.07 episodes per patient (P = .86 at 3 months; P = .32 at 1 year). Among ARE 2R or greater, the CsA group displayed 0.51 +/- 0.70 and 0.91 +/- 0.95 episodes per patient at 3 months and 1 year, while the FK group showed 0.15 +/- 0.38 and 0.31 +/- 0.63 episodes, respectively (P = .09 at 3 months; P = .016 at 1 year). Among type 3R ARE, the CsA group showed 0.11 +/- 0.32 and 0.13 +/- 0.34 episodes, whereas the FK group experienced 0.05 +/- 0.23 and 0.05 +/- 0.23 episodes at 3 months and 1 year, respectively (P = .44 at 3 months, P = .35 at 1 year). The freedom rate from 1R, 2R, and 3R ARE was therefore similar between the two groups (P = .76, P = .14, and P = .23, respectively). Induction with FK-RATG tended to reduce the number of type 2R and greater rejection episodes per patient at 1 year after transplantation compared to CsA-RATG.


Assuntos
Soro Antilinfocitário/uso terapêutico , Ciclosporina/uso terapêutico , Transplante de Coração/imunologia , Imunossupressores/uso terapêutico , Tacrolimo/uso terapêutico , Adulto , Animais , Inibidores de Calcineurina , Cardiomiopatias/cirurgia , Quimioterapia Combinada , Feminino , Seguimentos , Rejeição de Enxerto/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Coelhos , Estudos Retrospectivos , Fatores de Tempo
11.
Food Chem Toxicol ; 47(7): 1416-24, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19328220

RESUMO

Male rats were administered one of three biodiesels - soy oil methyl ester (SoME-2), canola oil methyl ester (CaME-2), and methyl ester of animal frying oil (FrAME-1) at 5, 50 and 500 mg/kg, or ultra-low sulphur diesel (ULSD) at 500 mg/kg. Control was administered the vehicle (corn oil) only. After 4-week treatment, serum methanol and formic acid were unchanged or minimally elevated in all treatment groups. Mild histopathological changes in the liver were observed in animals receiving 500 mg/kg biodiesels and ULSD but hepatomegaly, increased phase I and II drug-metabolizing enzyme activities and urinary ascorbic acid were found only in the ULSD group. The ULSD group had increased kidney weight, changes in kidney histopathology, and increased urinary albumin and N-acetylgluocosaminidase activity. Biodiesels and ULSD caused increase in hepatic acyl-CoA oxidase activity. ULSD and FrAME-1 caused decrease in serum free fatty acid while CaME-2 caused decreases in both serum triglycerides and free fatty acids. FrAME-1 produced an increase in liver protein carbonyls and ULSD caused increased liver glutathione. The results indicated that ULSD caused more histopathological and biochemical effects than biodiesels. Biodiesels produced lipid effects and oxidative stress that were feedstock-dependent. The mechanisms and significance of increased hepatic acyl-CoA oxidase activity required further study.


Assuntos
Fontes de Energia Bioelétrica , Combustíveis Fósseis/toxicidade , Enxofre/análise , Administração Oral , Animais , Contagem de Células Sanguíneas , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Combustíveis Fósseis/análise , Hepatomegalia/induzido quimicamente , Hepatomegalia/patologia , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Testes de Função Hepática , Masculino , Metanol/análise , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Testículo/patologia
12.
Breast Cancer (Auckl) ; 3: 9-21, 2009 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-21556246

RESUMO

It is known that the steroid sulfatase (STS) and the estrogen sulfotransferase (EST1E1) are commonly expressed in human breast carcinomas. STS and EST1E1 combined action could maintain the equilibrium between sulfated (inactive) and unconjugated (active) estrogens, which might have effects on development of hormone dependent breast cancer.We studied the expression of the STS and EST1E1 in 88 breast carcinomas and 57 adjacent non-malignant tissues by immunohistochemistry. The results were correlated with the tumor expression of estrogen receptor α (ER-α) and ß (ER-ß), progesterone receptor A (PR-A) and B (PR-B) and the proliferation marker CDC47, the tumoral type and stage and the age at surgery.STS expression was higher in carcinoma specimens than in adjacent normal tissues, although not to a significant level (p = 0.064) and it was positively associated with CDC47 expression (p < 0.05). These observations support the hypothesis that STS is overexpressed in breast cancer and associated with a worse prognosis.EST1E1 was observed for the first time in the nuclei of epithelial and tumoral cells. Tumor expression of EST1E1 was positively correlated with ER-ß (p < 0.01) and PR-B (p < 0.05), two steroid receptors already associated with an improve prognosis for breast cancer.Controlling the STS overexpression in carcinomas could be a way to inhibit cancer growth. The significance of the association between EST1E1 and ER-ß or PR-B should be further studied since these two receptors are transcription activators and may regulate the expression of protective enzymes like EST1E1.

13.
J Steroid Biochem Mol Biol ; 112(4-5): 194-200, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18996480

RESUMO

Estrogens play an important role in the development and progression of breast cancer. 17beta-Hydroxysteroid dehydrogenase (17beta-HSD) type 2 and type 5 are involved in sex steroid metabolism. 17beta-HSD type 2 converts estradiol to estrone while 17beta-HSD type 5 converts androstenedione to testosterone. Using immunocytochemistry, we have studied the expression of 17beta-HSD type 2 and type 5 in 50 specimens of breast carcinoma and adjacent non-malignant tissues. The results were correlated with the estrogen receptor alpha (ERalpha) and beta (ERbeta), progesterone receptor A (PRA) and B (PRB), androgen receptor and CDC47 and with the tumor stage, tumor size, nodal status and menopausal status. 17beta-HSD type 2 was expressed in 20% and 17beta-HSD type 5 in 56% of breast cancer specimens. In adjacent normal tissues, both enzymes were highly expressed in almost all the patients. No significant association could be found between the expression of 17beta-HSD type 2 and 17beta-HSD type 5 and between the expression of each enzyme and the clinicopathological parameters studied. The decrease in 17beta-HSD type 2 and 17beta-HSD type 5 expressions in breast cancer may play a predominant role in the development and/or progression of the cancer by modifying the intratumoral levels of estrogens and androgens.


Assuntos
17-Hidroxiesteroide Desidrogenases/biossíntese , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Mama/enzimologia , 3-Hidroxiesteroide Desidrogenases , Adulto , Idoso , Membro C3 da Família 1 de alfa-Ceto Redutase , Animais , Estradiol Desidrogenases , Receptor alfa de Estrogênio/biossíntese , Receptor beta de Estrogênio/biossíntese , Feminino , Humanos , Hidroxiprostaglandina Desidrogenases , Pessoa de Meia-Idade , Coelhos , Receptores Androgênicos/biossíntese , Receptores de Progesterona/biossíntese
14.
Gastroenterol Clin Biol ; 32(2): 164-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18496891

RESUMO

We report the case of a young man who developed multiple liver cell adenomas 13 years after a mesentericocaval shunt. Radiological findings did not provide diagnosis. Histological findings of two biopsied nodules were compatible with liver cell adenoma. Our patient had no known risk factors for liver cell adenomas. We discuss the hypothesis that disturbed hepatic vascularisation could promote the development of liver cell adenomas.


Assuntos
Adenoma de Células Hepáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico , Derivação Portossistêmica Cirúrgica , Adulto , Biópsia por Agulha , Doença de Caroli/diagnóstico , Seguimentos , Humanos , Cirrose Hepática/congênito , Masculino , Rim Policístico Autossômico Recessivo/diagnóstico , Ultrassonografia de Intervenção
15.
Toxicol Lett ; 176(2): 93-103, 2008 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-18077114

RESUMO

Although human populations are continuously exposed to complex mixtures of contaminants, the effects of such exposure on the developing brain transcriptome are poorly characterized. Rats were exposed perinatally to the northern contaminant mixture (NCM) which was designed to reflect the blood contaminant profile of Canadian arctic populations, to components of the NCM administered separately (methylmercury (MeHg), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCs)) or to the goitrogen propylthiouracyl. Post-natal day (PND) 14 cerebellum global gene expression resulting from such exposures was investigated using high-density cDNA microarrays. Fifty known genes were identified as differentially expressed between the control group and at least one other treatment group. The microarray data were validated by quantitative PCR (qPCR) on a subset of 10 genes. The differentially expressed genes are involved in a variety of processes, including nerve cell differentiation, migration, myelination and synaptic transmission. The comparison of cerebellum gene expression profiles resulting from exposure to the NCM and its individual components in male and female pups revealed that (i) gender is a crucial biological variable influencing genomic response to environmental contaminants and (ii) contaminant co-exposure significantly masks the effects of individual mixture components on cerebellum gene expression.


Assuntos
Cerebelo/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Perfilação da Expressão Gênica/métodos , Praguicidas/toxicidade , Animais , Animais Recém-Nascidos , Proteínas de Ligação ao Cálcio/genética , Cerebelo/metabolismo , Análise por Conglomerados , Poluentes Ambientais/química , Proteínas da Matriz Extracelular/genética , Feminino , Fatores de Troca do Nucleotídeo Guanina/genética , Hidrocarbonetos Clorados/química , Hidrocarbonetos Clorados/toxicidade , Lactação , Masculino , Exposição Materna , Compostos de Metilmercúrio/química , Compostos de Metilmercúrio/toxicidade , Neuropeptídeos/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Praguicidas/química , Praguicidas/classificação , Bifenilos Policlorados/química , Bifenilos Policlorados/toxicidade , Gravidez , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Ribossômicas/genética , Fatores Sexuais
16.
J Steroid Biochem Mol Biol ; 108(1-2): 102-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17933518

RESUMO

Dehydroepiandrosterone (DHEA), the major steroid precursor of androgens and estrogens produced in peripheral tissues in primates, has been shown to exert chemopreventive effect on the development of carcinogen-induced rat mammary tumors. Since little is known on the effect of DHEA administration on mammary gland physiology and histology, we have studied the effect of long-term administration of DHEA to normal female monkey and rat on mammary gland histology as well as on serum DHEA, DHEA sulphate (DHEA-S), testosterone and estradiol levels. In monkeys, DHEA treatment (2 or 10 mg/(kg b.w.day)) induced a dose-related increase in serum DHEA and DHEA-S (above 20-fold) levels. At the highest dose of DHEA, serum testosterone levels were significantly increased (three- to fourfold), while serum estradiol concentration was not modified. DHEA treatment did not modify the histological characteristics of monkey mammary glands. In the rat, following DHEA administration (10 or 100 mg/(kg b.w.day)), a dose-related marked increase in serum DHEA and DHEA-S was observed. Serum testosterone was also increased in DHEA-treated animals, while no significant changes in serum estradiol levels were detected. As in the monkey, the histology of the female rat mammary gland remained unchanged following long-term treatment with any of the two doses of DHEA.


Assuntos
Desidroepiandrosterona/farmacologia , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos , Administração Oral , Animais , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/sangue , Avaliação Pré-Clínica de Medicamentos , Feminino , Macaca fascicularis , Ratos , Ratos Sprague-Dawley , Esteroides/sangue , Fatores de Tempo
17.
BMC Cancer ; 7: 214, 2007 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-18021430

RESUMO

BACKGROUND: We conducted a case-control study to evaluate the role of UDP-glucuronosyltransferase 1A7 (UGT1A7) polymorphisms in the onset of hepatocellular carcinoma (HCC). METHODS: The study included 165 patients with HCC, 134 with cirrhosis and 142 controls without liver disease, matched for age and hospital. All were men younger than 75 years. HCC and cirrhosis patients were stratified according to time since cirrhosis diagnosis. RESULTS: We found a positive association between the UGT1A7*3/*3 genotype and HCC when the comparison was restricted to patients whose disease was of viral origin [OR = 3.4 (0.3-45)] but a negative association when it included only alcoholic patients [OR = 0.1 (0.02-0.6), p = 0.01]. CONCLUSION: Our study shows that UGT1A7 may play a role in hepatocellular carcinogenesis and that this role may differ according to the primary cause of the cirrhosis.


Assuntos
Carcinoma Hepatocelular/genética , Glucuronosiltransferase/genética , Antígenos de Superfície da Hepatite B/sangue , Anticorpos Anti-Hepatite C/sangue , Neoplasias Hepáticas/genética , Polimorfismo Genético/genética , Adulto , Idoso , Consumo de Bebidas Alcoólicas , Alelos , Biomarcadores/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Estudos de Casos e Controles , Hepatite B/complicações , Hepatite B/enzimologia , Hepatite C/complicações , Hepatite C/enzimologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/enzimologia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Fatores de Risco , Testes Sorológicos
18.
Water Sci Technol ; 56(6): 57-64, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17898444

RESUMO

In this paper, two approaches to data mining of time series have been tested and compared. Both methods are based on the wavelet decomposition of data series and allow the localization of important characteristics of a time series in both the time and frequency domain. The first method is a common method based on the analysis of wavelet power spectra. The second approach is new to the applied field of urban water networks and provides a qualitative description of the data series based on the cubic spline wavelet decomposition of the data. It is shown that wavelet power spectra indicate important and basic characteristics of the data but fail to provide detailed information of the underlying phenomena. In contrast, the second method allows the extraction of more and more detailed information that is important in a context of process monitoring and diagnosis.


Assuntos
Cidades , Armazenamento e Recuperação da Informação/métodos , Abastecimento de Água/análise , Modelos Teóricos , Reprodutibilidade dos Testes , Poluição da Água/análise , Poluição da Água/prevenção & controle , Abastecimento de Água/estatística & dados numéricos
19.
J Neuroendocrinol ; 19(6): 426-31, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17388940

RESUMO

It is well documented that oestrogen suppresses food intake by an action at the hypothalamic level. Using in situ hybridisation, we studied the effect of castration (CX) and short-term administration of oestradiol (E2) in CX female mice for three neuropeptides involved in feeding behaviour: two anorexigenic peptides, (i) the pro-opiomelanocortin (POMC)-derived peptide alpha-melanocyte-stimulating hormone and (ii) corticotrophin-releasing hormone (CRH), and the orexigenic peptide, (iii) neuropeptide Y (NPY). POMC-expressing neurones were mostly laterally located in the arcuate nucleus. POMC mRNA expression was decreased following CX and a single injection of E2 induced an increase in mRNA levels at 12- and 24-h time intervals. In the parvocellular area of the paraventricular nucleus, CRH mRNA levels were similarly decreased after CX and completely restored to normal levels at 12 and 24 h following E2 injection. On the other hand, the levels of NPY mRNA expressed in neurones located in the inner zone of the arcuate nucleus were increased by CX and decreased to the levels observed in intact animals by E2 injection (3-24 h). The present data suggest that oestrogen might exert an anorexigenic action by stimulating POMC and CRH mRNA expression and decreasing NPY mRNA expression in the hypothalamus.


Assuntos
Regulação do Apetite/fisiologia , Hormônio Liberador da Corticotropina/metabolismo , Estradiol/fisiologia , Hipotálamo/metabolismo , Neuropeptídeo Y/metabolismo , Pró-Opiomelanocortina/metabolismo , Animais , Hormônio Liberador da Corticotropina/genética , Feminino , Hipotálamo/citologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Neuropeptídeo Y/genética , Pró-Opiomelanocortina/genética , RNA Mensageiro/metabolismo
20.
Neuroscience ; 145(1): 110-5, 2007 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-17207581

RESUMO

The enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) converts the inactive 11-dehydrocorticosterone into the active glucocorticoid corticosterone. There is accumulating evidence indicating widespread expression of 11beta-HSD1 in the brain. However, there is little information about regulation of 11beta-HSD1 expression in this tissue. Using in situ hybridization involving use of 35S-labeled cRNA probe, we have studied the distribution of cells expressing 11beta-HSD1 mRNA in the male mouse forebrain as well as the effects of adrenalectomy (ADX) and acute administration of corticosterone (3 and 24 h) on 11beta-HSD1 mRNA levels. Cells expressing 11beta-HSD1 mRNA were mostly detected in the cerebral cortex, hippocampus, amygdala and medial preoptic area, with the highest expression in the cerebral cortex (retrosplenial granular area) and hippocampus (CA3 and granular layer of the gyrus dentatus). Seven days following ADX, 11beta-HSD mRNA levels were increased by 50% in the gyrus dentatus, by 100% in the CA3 area, and 105% in the cerebral cortex. Administration of corticosterone to ADX mice induced a significant decrease in mRNA, in both the hippocampus and cerebral cortex so that, at the 24 h time interval, the levels were similar to those observed in intact mice. These results clearly indicate that circulating corticosterone is downregulating the expression of 11beta-HSD1 mRNA in the two forebrain areas studied. This downregulation might contribute to maintain low intracellular corticosterone levels in central regions and then prevent the deleterious effects induced by high glucocorticoid levels.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Prosencéfalo/enzimologia , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Adrenalectomia/métodos , Animais , Relação Dose-Resposta a Droga , Hibridização In Situ/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Fatores de Tempo
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