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1.
Brain Sci ; 14(6)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38928616

RESUMEN

Glucagon-like peptide-1 (GLP-1) is involved in a range of central and peripheral pathways related to appetitive behavior. Hence, this study explored the effects of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on substance and behavioral addictions, including alcohol, caffeine, nicotine, cannabis, psychostimulants, compulsive shopping, and sex drive/libido. Data were collected from various social platforms. Keywords related to GLP-1 RAs and substance/behavioral addiction were used to extract relevant comments. The study employed a mixed-methods approach to analyze online discussions posted from December 2019 to June 2023 and collected using a specialized web application. Reddit entries were the focus here due to limited data from other platforms, such as TikTok and YouTube. A total of 5859 threads and related comments were extracted from six subreddits, which included threads about GLP-1 RAs drugs and associated brand names. To obtain relevant posts, keywords related to potential substance use and compulsive behavior were selected. Further analysis involved two main steps: (1) manually coding posts based on users' references to the potential impact of GLP-1 RAs on substance use and non-substance habits, excluding irrelevant or unclear comments; (2) performing a thematic analysis on the dataset of keywords, using AI-assisted techniques followed by the manual revision of the generated themes. Second, a thematic analysis was performed on the keyword-related dataset, using AI-assisted techniques followed by the manual revision of the generated themes. In total, 29.75% of alcohol-related; 22.22% of caffeine-related; and 23.08% of nicotine-related comments clearly stated a cessation of the intake of these substances following the start of GLP-1 RAs prescription. Conversely, mixed results were found for cannabis intake, and only limited, anecdotal data were made available for cocaine, entactogens, and dissociative drugs' misuse. Regarding behavioral addictions, 21.35% of comments reported a compulsive shopping interruption, whilst the sexual drive/libido elements reportedly increased in several users. The current mixed-methods approach appeared to be a useful tool in gaining insight into complex topics such as the effects of GLP-1 RAs on substance and non-substance addiction-related disorders; some GLP-1 RA-related mental health benefits could also be inferred from here. Overall, it appeared that GLP-1 RAs may show the potential to target both substance craving and maladaptive/addictive behaviors, although further empirical research is needed.

3.
Pharmaceuticals (Basel) ; 16(7)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37513906

RESUMEN

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.

4.
BMC Anesthesiol ; 18(1): 96, 2018 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-30053804

RESUMEN

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.


Asunto(s)
Anestésicos/farmacología , Núcleo Arqueado del Hipotálamo/metabolismo , Conducta Alimentaria/efectos de los fármacos , Neuropéptido Y/biosíntesis , Proopiomelanocortina/biosíntesis , Animales , Masculino , Ratones
5.
Rep Prog Phys ; 79(4): 046901, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27007555

RESUMEN

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.

6.
Pharmacogenomics J ; 15(1): 13-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24980785

RESUMEN

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.


Asunto(s)
Cultura , Insuficiencia Cardíaca/psicología , Trasplante de Corazón/psicología , Esperanza , Farmacogenética , Receptores de Trasplantes/psicología , Adulto , Anciano , Estudios Transversales , Femenino , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/cirugía , Humanos , Masculino , Persona de Mediana Edad , Farmacogenética/tendencias
7.
Int J Toxicol ; 31(5): 454-66, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22914890

RESUMEN

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.


Asunto(s)
Disruptores Endocrinos/toxicidad , Contaminantes Ambientales/toxicidad , Estradiol/metabolismo , Hidrocarburos Clorados/toxicidad , Compuestos de Metilmercurio/toxicidad , Plaguicidas/toxicidad , Animales , Catecol O-Metiltransferasa/genética , Sistema Enzimático del Citocromo P-450/genética , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Intercambio Materno-Fetal , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas , Ratas Sprague-Dawley
8.
Water Res ; 46(20): 6857-67, 2012 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22196044

RESUMEN

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.


Asunto(s)
Material Particulado , Eliminación de Residuos Líquidos/métodos , Contaminantes del Agua , Simulación por Computador , Modelos Teóricos , Factores de Tiempo
9.
Water Sci Technol ; 64(9): 1898-905, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22020485

RESUMEN

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.


Asunto(s)
Aguas del Alcantarillado/análisis , Eliminación de Residuos Líquidos , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Análisis de la Demanda Biológica de Oxígeno , Fraccionamiento Químico , Ciudades , Geografía , Quebec , Lluvia , Calidad del Agua
10.
J Mol Endocrinol ; 44(5): 295-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20219854

RESUMEN

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.


Asunto(s)
Inhibidor de la Unión a Diazepam/metabolismo , Ayuno , Neuroglía/metabolismo , Neuropéptidos/metabolismo , Fragmentos de Péptidos/metabolismo , Animales , Regulación hacia Abajo , Epéndimo/metabolismo , Hipotálamo/metabolismo , Inyecciones Intraperitoneales , Insulina/administración & dosificación , Ventrículos Laterales/metabolismo , Leptina/administración & dosificación , Masculino , Ratones , Neuropéptidos/genética , Fragmentos de Péptidos/genética , Unión Proteica , Tercer Ventrículo/metabolismo , Transcripción Genética
11.
Transplant Proc ; 41(8): 3337-41, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19857745

RESUMEN

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.


Asunto(s)
Suero Antilinfocítico/uso terapéutico , Ciclosporina/uso terapéutico , Trasplante de Corazón/inmunología , Inmunosupresores/uso terapéutico , Tacrolimus/uso terapéutico , Adulto , Animales , Inhibidores de la Calcineurina , Cardiomiopatías/cirugía , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Rechazo de Injerto/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Conejos , Estudios Retrospectivos , Factores de Tiempo
12.
Food Chem Toxicol ; 47(7): 1416-24, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19328220

RESUMEN

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.


Asunto(s)
Fuentes de Energía Bioeléctrica , Combustibles Fósiles/toxicidad , Azufre/análisis , Administración Oral , Animales , Recuento de Células Sanguíneas , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Combustibles Fósiles/análisis , Hepatomegalia/inducido químicamente , Hepatomegalia/patología , Riñón/patología , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/patología , Pruebas de Función Hepática , Masculino , Metanol/análisis , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Testículo/patología
13.
Breast Cancer (Auckl) ; 3: 9-21, 2009 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-21556246

RESUMEN

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.

14.
J Steroid Biochem Mol Biol ; 112(4-5): 194-200, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18996480

RESUMEN

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.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas/biosíntesis , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Mama/enzimología , 3-Hidroxiesteroide Deshidrogenasas , Adulto , Anciano , Miembro C3 de la Familia 1 de las Aldo-Ceto Reductasas , Animales , Estradiol Deshidrogenasas , Receptor alfa de Estrógeno/biosíntesis , Receptor beta de Estrógeno/biosíntesis , Femenino , Humanos , Hidroxiprostaglandina Deshidrogenasas , Persona de Mediana Edad , Conejos , Receptores Androgénicos/biosíntesis , Receptores de Progesterona/biosíntesis
15.
Gastroenterol Clin Biol ; 32(2): 164-6, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18496891

RESUMEN

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.


Asunto(s)
Adenoma de Células Hepáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico , Derivación Portosistémica Quirúrgica , Adulto , Biopsia con Aguja , Enfermedad de Caroli/diagnóstico , Estudios de Seguimiento , Humanos , Cirrosis Hepática/congénito , Masculino , Riñón Poliquístico Autosómico Recesivo/diagnóstico , Ultrasonografía Intervencional
16.
J Steroid Biochem Mol Biol ; 108(1-2): 102-8, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17933518

RESUMEN

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.


Asunto(s)
Deshidroepiandrosterona/farmacología , Glándulas Mamarias Animales/citología , Glándulas Mamarias Animales/efectos de los fármacos , Administración Oral , Animales , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/sangre , Evaluación Preclínica de Medicamentos , Femenino , Macaca fascicularis , Ratas , Ratas Sprague-Dawley , Esteroides/sangre , Factores de Tiempo
17.
Toxicol Lett ; 176(2): 93-103, 2008 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-18077114

RESUMEN

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.


Asunto(s)
Cerebelo/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Perfilación de la Expresión Génica/métodos , Plaguicidas/toxicidad , Animales , Animales Recién Nacidos , Proteínas de Unión al Calcio/genética , Cerebelo/metabolismo , Análisis por Conglomerados , Contaminantes Ambientales/química , Proteínas de la Matriz Extracelular/genética , Femenino , Factores de Intercambio de Guanina Nucleótido/genética , Hidrocarburos Clorados/química , Hidrocarburos Clorados/toxicidad , Lactancia , Masculino , Exposición Materna , Compuestos de Metilmercurio/química , Compuestos de Metilmercurio/toxicidad , Neuropéptidos/genética , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Plaguicidas/química , Plaguicidas/clasificación , Bifenilos Policlorados/química , Bifenilos Policlorados/toxicidad , Embarazo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Ribosómicas/genética , Factores Sexuales
18.
BMC Cancer ; 7: 214, 2007 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-18021430

RESUMEN

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.


Asunto(s)
Carcinoma Hepatocelular/genética , Glucuronosiltransferasa/genética , Antígenos de Superficie de la Hepatitis B/sangre , Anticuerpos contra la Hepatitis C/sangre , Neoplasias Hepáticas/genética , Polimorfismo Genético/genética , Adulto , Anciano , Consumo de Bebidas Alcohólicas , Alelos , Biomarcadores/sangre , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/diagnóstico , Estudios de Casos y Controles , Hepatitis B/complicaciones , Hepatitis B/enzimología , Hepatitis C/complicaciones , Hepatitis C/enzimología , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/enzimología , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/diagnóstico , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos , Factores de Riesgo , Pruebas Serológicas
19.
Water Sci Technol ; 56(6): 57-64, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17898444

RESUMEN

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.


Asunto(s)
Ciudades , Almacenamiento y Recuperación de la Información/métodos , Abastecimiento de Agua/análisis , Modelos Teóricos , Reproducibilidad de los Resultados , Contaminación del Agua/análisis , Contaminación del Agua/prevención & control , Abastecimiento de Agua/estadística & datos numéricos
20.
J Neuroendocrinol ; 19(6): 426-31, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17388940

RESUMEN

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.


Asunto(s)
Regulación del Apetito/fisiología , Hormona Liberadora de Corticotropina/metabolismo , Estradiol/fisiología , Hipotálamo/metabolismo , Neuropéptido Y/metabolismo , Proopiomelanocortina/metabolismo , Animales , Hormona Liberadora de Corticotropina/genética , Femenino , Hipotálamo/citología , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismo , Neuropéptido Y/genética , Proopiomelanocortina/genética , ARN Mensajero/metabolismo
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