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1.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-823991

RESUMEN

Synthetic cathinones are new psychoactive substances that represent a health risk worldwide. For most of the 130 reported compounds, information about toxicology and/or metabolism is not available, which hampers their detection (and subsequent medical treatment) in intoxication cases. The principles of forensic analytical chemistry and the use of powerful analytical techniques are indispensable for stab-lishing the most appropriate biomarkers for these substances. Human metabolic fate of synthetic cathinones can be assessed by the analysis of urine and blood obtained from authentic consumers;however, this type of samples is limited and difficult to access. In this work, the metabolic behaviour of three synthetic cathinones (4-CEC, 4-CPrC and 5-PPDi) and one amphetamine (3-FEA) has been evalu-ated by incubation with pooled human hepatocytes and metabolite identification has been performed by high-resolution mass spectrometry. This in vitro approach has previously shown its feasibility for obtaining excretory human metabolites. 4-CEC and 3-FEA were not metabolised, and for 4-CPrC only two minor metabolites were obtained. On the contrary, for the recently reported 5-PPDi, twelve phase I metabolites were elucidated. Up to our knowledge, this is the first metabolic study of an indanyl-cathinone. Data reported in this paper will allow the detection of these synthetic stimulants in intoxi-cation cases, and will facilitate future research on the metabolic behaviour of other indanyl-based cathinones.

4.
Peptides ; 31(2): 284-90, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19944725

RESUMEN

We have previously demonstrated that pregnant ovine endometrium expresses the gastrin-releasing peptide (GRP) gene at a high level following conceptus implantation. Here we report the isolation, characterization and biological activity of ovine GRP 1-46, the primary product of this gene in the pregnant endometrium. Full thickness 125-140-day pregnant sheep uterus (term is 145 day) was homogenized in 80% acetonitrile/2% trifluoroacetic acid (1:7 ACN/TFA), concentrated on reverse-phase C18 cartridges and chromatographed successively on gel filtration (Sephadex G-50) and reverse-phase HPLC (C18 muBondapak). Purification was monitored by RIA. Purified GRP peptide was analysed by mass spectrometry giving a major mass ion at 4963 which corresponds exactly to GRP 1-46. Other mass ions from pro-GRP did not contain a biologically active N-terminus or antigenic determinant. Proteolytic cleavage of pro-GRP to give rise to GRP(1-46) would require preferential cleavage at the Glu-Glu bond by a Glu-C2-like enzyme, rather than the trypsin-like and C-terminal amidation enzymes (PAM) that produce GRP(18-27) and GRP(1-27) in other tissues. GRP 1-46 was synthesized and receptor binding and biological activity tested on a range of rodent and human cell lines that express GRP-related receptors GRPR, NMBR and BRS3. GRP 1-46 bound GRPR and NMBR with low affinity, and mobilized inositol phosphate in cell lines expressing the GRPR and NMBR, but not BRS-3. This study describes a new processed product of the GRP gene, GRP 1-46, which is highly expressed in the pregnant sheep endometrium and which acts as a weak agonist at the GRPR and NMBR.


Asunto(s)
Endometrio/química , Péptido Liberador de Gastrina/aislamiento & purificación , Péptido Liberador de Gastrina/farmacología , Secuencia de Aminoácidos , Animales , Línea Celular , Línea Celular Tumoral , Femenino , Péptido Liberador de Gastrina/análisis , Péptido Liberador de Gastrina/metabolismo , Humanos , Indoles/farmacología , Fosfatos de Inositol/metabolismo , Ratones , Datos de Secuencia Molecular , Peso Molecular , Péptidos/genética , Embarazo , Unión Proteica/fisiología , Precursores de Proteínas/genética , Piridinas/farmacología , Ratas , Receptores de Bombesina/antagonistas & inhibidores , Receptores de Bombesina/genética , Receptores de Bombesina/metabolismo , Ovinos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Transfección , Fosfolipasas de Tipo C/metabolismo
5.
Horm Metab Res ; 40(7): 459-66, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18393174

RESUMEN

Long-term exposure of normal rats to a fructose-enriched diet or drinking water is currently used as an animal model for experimental insulin resistance. The present study deals with a comparison between rats given access to either a fructose-enriched diet or fructose-enriched drinking water. In both situations, a decrease in food intake and body weight gain, and the induction of insulin resistance with intolerance to D-glucose despite increased secretory response to the aldohexose of insulin-producing cells were documented. Moreover, the rats exposed to exogenous D-fructose displayed a lesser sensitivity to overnight fasting than control animals, in terms of the alteration of glucose homeostasis and reduction of the ratio between plasma insulin and D-glucose concentration. It is also shown that the fructose-induced insulin resistance, as assessed in a hyperinsulinemic-euglycemic clamp, represents a phenomenon reversed within 15-30 days after removal of the keto-hexose from the drinking water.


Asunto(s)
Fructosa/efectos adversos , Resistencia a la Insulina , Animales , Glucemia/análisis , Glucemia/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Dieta/efectos adversos , Ingestión de Líquidos/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Alimentos/fisiología , Fructosa/farmacología , Prueba de Tolerancia a la Glucosa/métodos , Insulina/sangre , Resistencia a la Insulina/fisiología , Masculino , Ratas , Ratas Wistar , Inanición/metabolismo , Factores de Tiempo , Aumento de Peso/efectos de los fármacos
6.
Horm Metab Res ; 38(12): 789-98, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17163352

RESUMEN

Presently an insufficient supply of long-chain polyunsaturated omega3 fatty acid is prevalent in Western populations leading to potential metabolic consequences. Based on this fact, this study deals mainly with various aspects of lipid metabolism in second generation female omega3-depleted rats. The parametrial fat and body weights were higher in omega3-depleted than control animals. This coincided with liver steatosis but did not alter heart triglyceride/phospholipid ratio. The net uptake of [U-14C] palmitate by adipocytes was also higher in omega3-depleted rats than in control animals. The uptake of D-[U- 4C] glucose or [1,2 (-14)C] acetate by adipocytes was lower, however in omega3-depleted than control animals and was unaffected by insulin in the former as distinct from latter animals. Despite comparable basal lipolysis, the increase in glycerol output from adipocytes provoked by theophylline was higher in omega3-depleted than control rats. The fatty acid pattern of lipids in adipose tissue was characterized in the omega3-depleted rats by a much lower omega3 content, higher apparent Delta 9-saturase and elongase activities, lower efficiency for the conversion of C18:2omega6 to C20:4omega6 and higher efficiency for the conversion of C18:3omega3 to C20:5omega3. These features were compared to those prevailing in liver and plasma lipids. The present study thus extends knowledge on the alteration of lipid metabolism resulting from a deficiency in long-chain polyunsaturated omega3 fatty acids.


Asunto(s)
Adipocitos/metabolismo , Ácidos Grasos Omega-3/fisiología , Acetatos/farmacocinética , Animales , Distribución de la Grasa Corporal , Peso Corporal , Ácidos Grasos Omega-3/metabolismo , Femenino , Glucosa/farmacocinética , Metabolismo de los Lípidos , Lipólisis , Hígado/química , Miocardio/química , Palmitatos/farmacocinética , Fosfolípidos/análisis , Ratas , Triglicéridos/análisis
7.
Horm Metab Res ; 37(5): 275-80, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15971149

RESUMEN

Several protein kinases were recently proposed for involvement in GLP-1-stimulated D-glucose transport in skeletal muscle from both normal subjects and type 2 diabetic patients. This study was mainly aimed at investigating the effect of potential inhibitors of distinct protein kinases and protein phosphatase-1 upon insulin- and GLP-1-stimulated 2-deoxy-D-glucose net uptake by normal rat skeletal muscle. The basal uptake of the D-glucose analog was decreased by wortmannin--a phosphatidylinositol-3-kinase inhibitor--, PD98059--a mitogen-activated protein kinases inhibitor--, and TNFalpha--a protein phosphatase-1 inhibitor--, but not by either rapamycin--a p70s6 kinase inhibitor--, or H-7--, a protein kinase C inhibitor--. The enhancing action of both insulin and GLP-1 upon 2-deoxy-D-glucose transport was abolished by PD98059 and H-7, but largely unaffected by TNFalpha. Wortmannin and rapamycin preferentially affected the response to GLP-1 and insulin, respectively. These findings thus document both analogies and dissimilarities in the participation of the concerned enzymes in the stimulant action of insulin versus GLP-1 upon D-glucose transport in normal rat skeletal muscle.


Asunto(s)
Desoxiglucosa/metabolismo , Glucagón/farmacología , Músculo Esquelético/metabolismo , Fragmentos de Péptidos/farmacología , Proteínas Quinasas/metabolismo , Precursores de Proteínas/farmacología , Animales , Transporte Biológico/efectos de los fármacos , Diabetes Mellitus Tipo 2/metabolismo , Inhibidores Enzimáticos/farmacología , Péptido 1 Similar al Glucagón , Técnicas de Cultivo de Órganos , Ratas , Ratas Wistar
8.
J Endocrinol ; 180(3): 389-98, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15012593

RESUMEN

Glucagon-like peptide-1 (GLP-1), an incretin with glucose-dependent insulinotropic and insulin-independent antidiabetic properties, has insulin-like effects on glucose metabolism in extrapancreatic tissues participating in overall glucose homeostasis. These effects are exerted through specific receptors not associated with cAMP, an inositol phosphoglycan being a possible second messenger. In rat hepatocytes, activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB), protein kinase C (PKC) and protein phosphatase 1 (PP-1) has been shown to be involved in the GLP-1-induced stimulation of glycogen synthase. We have investigated the role of enzymes known or suggested to mediate the actions of insulin in the GLP-1-induced increase in glycogen synthase a activity in rat skeletal muscle strips. We first explored the effect of GLP-1, compared with that of insulin, on the activation of PI3K, PKB, p70s6 kinase (p70s6k) and p44/42 mitogen-activated protein kinases (MAPKs) and the action of specific inhibitors of these kinases on the insulin- and GLP-1-induced increment in glycogen synthase a activity. The study showed that GLP-1, like insulin, activated PI3K/PKB, p70s6k and p44/42. Wortmannin (a PI3K inhibitor) reduced the stimulatory action of insulin on glycogen synthase a activity and blocked that of GLP-1, rapamycin (a 70s6k inhibitor) did not affect the action of GLP-1 but abolished that of insulin, PD98059 (MAPK inhibitor) was ineffective on insulin but blocked the action of GLP-1, okadaic acid (a PP-2A inhibitor) and tumour necrosis factor-alpha (a PP-1 inhibitor) were both ineffective on GLP-1 but abolished the action of insulin, and Ro 31-8220 (an inhibitor of some PKC isoforms) reduced the effect of GLP-1 while completely preventing that of insulin. It was concluded that activation of PI3K/PKB and MAPKs is required for the GLP-1-induced increment in glycogen synthase a activity, while PKC, although apparently participating, does not seem to play an essential role; unlike in insulin signaling, p70s6k, PP-1 and PP-2A do not seem to be needed in the action of GLP-1 upon glycogen synthase a activity in rat muscle.


Asunto(s)
Glucagón/farmacología , Músculo Esquelético/metabolismo , Fragmentos de Péptidos/farmacología , Precursores de Proteínas/farmacología , Proteínas Serina-Treonina Quinasas , Transducción de Señal/fisiología , Androstadienos/farmacología , Animales , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Glucagón/metabolismo , Péptido 1 Similar al Glucagón , Glucógeno Sintasa/metabolismo , Técnicas In Vitro , Indoles/farmacología , Insulina/farmacología , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Músculo Esquelético/efectos de los fármacos , Ácido Ocadaico/farmacología , Fragmentos de Péptidos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Fosfoproteínas Fosfatasas/metabolismo , Proteína Fosfatasa 1 , Precursores de Proteínas/metabolismo , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Ratas , Ratas Wistar , Proteínas Quinasas S6 Ribosómicas 70-kDa/antagonistas & inhibidores , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Sirolimus/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Wortmanina
9.
Cir Pediatr ; 14(3): 129-31, 2001 Jul.
Artículo en Español | MEDLINE | ID: mdl-11547636

RESUMEN

An acute gastric volvulus in a 10 years old boy with Smith-Lemli-Opitz syndrome is reported. He was immediately operated on and an organoaxial volvulus secondary to spleen agenesia was found. No other visceral malformation was present. Because of gastric ischemia, a second-look procedure was performed 48 hours later in order to asses necrosis extent. Gastric fundus had to be resected and the stomach was definitively fixed to the abdominal wall. Clinical, radiological and therapeutic characteristics of this unusual pathology are reviewed.


Asunto(s)
Síndrome de Smith-Lemli-Opitz/fisiopatología , Bazo/anomalías , Vólvulo Gástrico/etiología , Vólvulo Gástrico/cirugía , Enfermedad Aguda , Niño , Humanos , Masculino , Vólvulo Gástrico/diagnóstico
10.
Cir. pediátr ; 14(3): 129-131, jul. 2001.
Artículo en Es | IBECS | ID: ibc-14231

RESUMEN

Presentamos un caso de vólvulo gástrico agudo en un niño de 10 años con síndrome de Smith-Lemli-Opitz. El paciente fue intervenido con carácter urgente hallando un vólvulo organoxial secundario a una agenesia de bazo en ausencia de otras alteraciones viscerales. Ante el importante compromiso vascular se realizó una revisión quirúrgica 48 horas más tarde para valorar la extensión de la necrosis gástrica procediendose a la resección del fundus y a la fijación definitiva del estómago. Se revisan las características clínicas, radiológicas y terapéuticas de esta infrecuente patología (AU)


Asunto(s)
Niño , Masculino , Humanos , Vólvulo Gástrico , Bazo , Síndrome de Smith-Lemli-Opitz , Enfermedad Aguda
11.
Artículo en Es | IBECS | ID: ibc-20923

RESUMEN

La brucelosis es una zoonosis cuyo reservorio lo constituyen los animales domésticos, en particular cabras, ovejas, vacas y cerdos. La enfermedad en nuestro medio se adquiere tras la ingestión de productos lácteos no controlados. La mujer embarazada no escapa a esta infección. En la comarca de Jerte la incidencia asciende a unos 300 casos por 105 habitantes, lo que la convierte en la zona de mayor endemia del país. Analizamos 16 casos de brucelosis asociados a la gestación en los dos últimos años, con los siguientes resultados: una gestante fue diagnosticada tras ingresar de urgencias por feto muerto intraútero a las 19 semanas y síndrome febril, resultando la serología y hemocultivos positivos. En otra se advirtió enfermedad aguda (hemocultivos positivos) a las 13 semanas y se instauró tratamiento con 600 mg/día de rifampicina, tras lo que se produjo un aborto espontáneo a las 16 semanas. La tercera paciente con infección activa se diagnosticó a las 24 semanas. Se le administró monoterapia con rifampicina a dosis de 600 mg/día durante 45 días, con lo que se negativizaron los hemocultivos posteriormente y evolucionaron favorablemente la gestación y el recién nacido. Los 13 casos restantes sin bacteriemia (hemocultivos negativos) fueron seguidos muy de cerca con serología y hemocultivos mensuales hasta finalizar la gestación, sin que aparecieran complicaciones ni se aplicara tratamiento médico a ninguna paciente (AU)


Asunto(s)
Adulto , Embarazo , Femenino , Humanos , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/etiología , Complicaciones del Embarazo/fisiopatología , Tetraciclinas/uso terapéutico , Brucelosis/diagnóstico , Brucelosis/complicaciones , Brucelosis/tratamiento farmacológico , Doxiciclina/uso terapéutico , Rifampin/uso terapéutico , Vacunación/métodos , Vacunación/veterinaria , Vacunación Masiva/métodos , Vacunación Masiva/veterinaria , Brucelosis/epidemiología , Brucelosis/fisiopatología , Brucelosis/microbiología , Brucelosis/virología , Rifampin/administración & dosificación
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