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1.
Nat Neurosci ; 27(2): 319-327, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38182834

RESUMEN

Pregnancy is a unique neuroplastic period in adult life. This longitudinal study tracked brain cortical changes during the peripartum period and explored how the type of childbirth affects these changes. We collected neuroanatomic, obstetric and neuropsychological data from 110 first-time mothers during late pregnancy and early postpartum, as well as from 34 nulliparous women evaluated at similar time points. During late pregnancy, mothers showed lower cortical volume than controls across all functional networks. These cortical differences attenuated in the early postpartum session. Default mode and frontoparietal networks showed below-expected volume increases during peripartum, suggesting that their reductions may persist longer. Results also pointed to different cortical trajectories in mothers who delivered by scheduled C-section. The main findings were replicated in an independent sample of 29 mothers and 24 nulliparous women. These data suggest a dynamic trajectory of cortical decreases during pregnancy that attenuates in the postpartum period, at a different rate depending on the brain network and childbirth type.


Asunto(s)
Madres , Periodo Posparto , Adulto , Embarazo , Femenino , Humanos , Estudios Longitudinales , Periodo Posparto/psicología , Madres/psicología
2.
Schizophr Bull ; 49(5): 1269-1280, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37467351

RESUMEN

BACKGROUND: Use of illegal stimulants is associated with an increased risk of psychotic disorder. However, the impact of stimulant use on odds of first-episode psychosis (FEP) remains unclear. Here, we aimed to describe the patterns of stimulant use and examine their impact on odds of FEP. METHODS: We included patients with FEP aged 18-64 years who attended psychiatric services at 17 sites across 5 European countries and Brazil, and recruited controls representative of each local population (FEP = 1130; controls = 1497). Patterns of stimulant use were described. We computed fully adjusted logistic regression models (controlling for age, sex, ethnicity, cannabis use, and education level) to estimate their association with odds of FEP. Assuming causality, we calculated the population-attributable fractions for stimulant use associated with the odds for FEP. FINDINGS: Prevalence of lifetime and recent stimulant use in the FEP sample were 14.50% and 7.88% and in controls 10.80% and 3.8%, respectively. Recent and lifetime stimulant use was associated with increased odds of FEP compared with abstainers [fully adjusted odds ratio 1.74,95% confidence interval (CI) 1.20-2.54, P = .004 and 1.62, 95% CI 1.25-2.09, P < .001, respectively]. According to PAFs, a substantial number of FEP cases (3.35% [95% CI 1.31-4.78] for recent use and 7.61% [95% CI 3.68-10.54] for lifetime use) could have been prevented if stimulants were no longer available and the odds of FEP and PAFs for lifetime and recent stimulant use varied across countries. INTERPRETATION: Illegal stimulant use has a significant and clinically relevant influence on FEP incidence, with varying impacts across countries.


Asunto(s)
Cannabis , Estimulantes del Sistema Nervioso Central , Trastornos Psicóticos , Humanos , Trastornos Psicóticos/epidemiología , Trastornos Psicóticos/psicología , Cannabis/efectos adversos , Europa (Continente) , Etnicidad , Incidencia
3.
Sci Rep ; 12(1): 4643, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35301397

RESUMEN

Vulnerability to addiction may be given by the individual's risk of developing an addiction during their lifetime. A challenge in the neurobiology of drug addiction is understanding why some people become addicted to drugs. Here, we used positron emission tomography (PET) and statistical parametric mapping (SPM) to evaluate changes in brain glucose metabolism in response to chronic morphine self-administration (MSA) in two rat strains with different vulnerability to drug abuse, Lewis (LEW) and Fischer 344 (F344). Four groups of animals were trained to self-administer morphine or saline for 15 days. 2-deoxy-2-[18F]-fluoro-D-glucose (FDG)-PET studies were performed on the last day of MSA (acquisition phase) and after 15 days of withdrawal. PET data were analyzed using SPM12. LEW-animals self-administered more morphine injections per session than F344-animals. We found significant brain metabolic differences between LEW and F344 strains in the cortex, hypothalamus, brainstem, and cerebellum. In addition, the different brain metabolic patterns observed after the MSA study between these rat strains indicate differences in the efficiency of neural substrates to translate the drug effects, which could explain the differences in predisposition to morphine abuse between one individual and another. These findings have important implications for the use of these rat strains in translational morphine and opiate research.


Asunto(s)
Glucosa , Morfina , Animales , Encéfalo/metabolismo , Glucosa/metabolismo , Humanos , Morfina/farmacología , Neuroimagen , Ratas , Ratas Endogámicas F344 , Ratas Endogámicas Lew , Especificidad de la Especie , Tomografía Computarizada por Rayos X
4.
J Pept Sci ; 26(12): e3282, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32840040

RESUMEN

Biomineralization is a highly regulated process where proteins/peptides-crystal interactions contribute to the shaping, phasing and aggregation of minerals. We have identified and synthesized a cementum attachment protein-derived peptide (CAP-pi), which corresponds to amino acids 40-53 of the N-terminal CAP domain (MASSDEDGTNGGAS) and its phosphorylated variant (MASpSpDEDGTNGGASp) (CAP-pip). The peptide is composed of polar and negatively charged amino acids, which are disordered, according to in silico analysis. Our results show that CAP-pi inhibits hydroxyapatite (HA) formation and growth. However, it possesses low capacity to inhibit calcium oxalate crystal growth. CAP-pip showed a stronger inhibitory effect on the formation and growth of HA. As well as a high capacity to inhibit calcium oxalate monohydrate growth, mainly due to adsorption on specific growth faces. Small peptides have many advantages over the full-size protein, including low-cost production and modulation characteristics that allow for structural changes. Our findings suggest that CAP-pip-derived peptide could possess therapeutic potential to prevent or treat pathological calcifications such as renal stones and vascular calcification.


Asunto(s)
Biomineralización/efectos de los fármacos , Durapatita/química , Péptidos/farmacología , Secuencia de Aminoácidos , Dicroismo Circular , Cristalización , Humanos , Péptidos/química , Péptidos/genética , Fosforilación
5.
Int J Mol Sci ; 21(4)2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32075221

RESUMEN

Human cementum protein 1 (CEMP1) is known to induce cementoblast and osteoblast differentiation and alkaline phosphatase (ALP) activity in human periodontal ligament-derived cells in vitro and promotes bone regeneration in vivo. CEMP1's secondary structure analysis shows that it has a random-coiled structure and is considered an Intrinsic Disordered Protein (IDP). CEMP1's short peptide sequences mimic the biological capabilities of CEMP1. However, the role and mechanisms of CEMP1's C-terminal-derived synthetic peptide (CEMP1-p4) in the canonical Wnt/ß-catenin signaling pathway are yet to be described. Here we report that CEMP1-p4 promotes proliferation and differentiation of Human Oral Mucosa Stem Cells (HOMSCs) by activating the Wnt/ß-catenin pathway. CEMP1-p4 stimulation upregulated the expression of ß-catenin and glycogen synthase kinase 3 beta (GSK-3B) and activated the transcription factors TCF1/7 and Lymphoid Enhancer binding Factor 1 (LEF1) at the mRNA and protein levels. We found translocation of ß-catenin to the nucleus in CEMP1-p4-treated cultures. The peptide also penetrates the cell membrane and aggregates around the cell nucleus. Analysis of CEMP1-p4 secondary structure revealed that it has a random-coiled structure. Its biological activities included the induction to nucleate hydroxyapatite crystals. In CEMP1-p4-treated HOMSCs, ALP activity and calcium deposits increased. Expression of Osterix (OSX), Runt-related transcription factor 2 (RUNX2), Integrin binding sialoproptein (IBSP) and osteocalcin (OCN) were upregulated. Altogether, these data show that CEMP1-p4 plays a direct role in the differentiation of HOMSCs to a "mineralizing-like" phenotype by activating the ß-catenin signaling cascade.


Asunto(s)
Mucosa Bucal/crecimiento & desarrollo , Osteogénesis/genética , Ligamento Periodontal/crecimiento & desarrollo , Proteínas/química , Células Madre/citología , Regeneración Ósea/genética , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Cemento Dental/metabolismo , Durapatita/metabolismo , Regulación del Desarrollo de la Expresión Génica/genética , Glucógeno Sintasa Quinasa 3 beta/genética , Humanos , Sialoproteína de Unión a Integrina/genética , Mucosa Bucal/citología , Mucosa Bucal/metabolismo , Osteoblastos/metabolismo , Osteocalcina/genética , Péptidos/química , Péptidos/genética , Ligamento Periodontal/citología , Ligamento Periodontal/metabolismo , Estructura Secundaria de Proteína , Proteínas/genética , Proteínas/ultraestructura , Factor de Transcripción Sp7/genética , Células Madre/metabolismo , Vía de Señalización Wnt/genética
6.
J Pept Sci ; 25(10): e3211, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31410920

RESUMEN

A cementum protein 1-derived peptide (CEMP1-p1) consisting of 20 amino acids from the CEMP1's N-terminus region: MGTSSTDSQQAGHRRCSTSN, and its role on the mineralization process in a cell-free system, was characterized. CEMP1-p1's physicochemical properties, crystal formation, and hydroxyapatite (HA) nucleation assays were performed. Crystals induced by CEMP1-p1 were analyzed by scanning electron microscopy, Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and atomic force microscopy. The results indicate that CEMP1-p1 lacks secondary structure, forms nanospheres that organize into three-dimensional structures, possesses affinity to HA, and induces its nucleation. CEMP1-p1 promotes the formation of spherical structures composed by densely packed prism-like crystals, which revealed a Ca/P ratio of 1.56, corresponding to HA. FTIR-ATR showed predominant spectrum peaks that correspond and are characteristic of HA and octacalcium phosphate (OCP). Analysis by XRD indicates that the crystals show planes with a preferential crystalline orientation for HA and for OCP. HRTEM showed interplanar distances that correspond to crystalline planes of HA and OCP. Crystals are composed by superimposed lamellae, which exhibit epitaxial growth, and each layer of the crystals is structured by nanocrystals. This study reveals that CEMP1-p1 regulates HA crystal formation, somehow mimicking the in vivo process of mineralized tissues bioformation.


Asunto(s)
Durapatita/química , Péptidos/química , Proteínas/química , Humanos
7.
FASEB J ; 33(1): 1167-1178, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30113883

RESUMEN

The use of recombinant proteins has revolutionized the development of biologic pharmaceuticals; however, they are not free of complications. Some have very high molecular weight, some demonstrate in vivo instability, and the high cost of producing them remains a major problem. On the other hand, it has been shown that peptides derived from active domains keep their biologic activity and can trigger events, such as osteogenesis and bone regeneration. Small peptides are advantageous because of their ease of synthesis and handling and their low immunogenic activity. The purpose of this study was to investigate the functions of a synthetic peptide, cementum protein 1-peptide1 (CEMP-1-p1), both in vitro and in vivo. Our results show that CEMP-1-p1 significantly enhanced the proliferation and differentiation of human periodontal ligament cells toward a mineralizing-like phenotype, as evidenced by increasing alkaline phosphatase (ALP)-specific activity and osterix, runt-related transcription factor (RUNX)-2, integrin binding sialoprotein, bone morphogenetic protein-2, osteocalcin, and cementum protein (CEMP)-1 expression at mRNA and protein levels. In vivo assays performed through standardized critical-size calvarial defects in rats treated with CEMP-1-p1 resulted in newly formed bone after 30 and 60 d. These data demonstrate that CEMP-1-p1 is an effective bioactive peptide for bone tissue regeneration. The application of this bioactive peptide may lead to implementing new strategies for the regeneration of bone and other mineralized tissues.-Correa, R., Arenas, J., Montoya, G., Hoz, L., López, S., Salgado, F., Arroyo, R., Salmeron, N., Romo, E., Zeichner-David, M., Arzate, H. Synthetic cementum protein 1-derived peptide regulates mineralization in vitro and promotes bone regeneration in vivo.


Asunto(s)
Regeneración Ósea/fisiología , Calcificación Fisiológica/fisiología , Péptidos/farmacología , Proteínas/fisiología , Animales , Biomarcadores/metabolismo , Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Humanos , Masculino , Modelos Animales , Ligamento Periodontal/citología , Ligamento Periodontal/metabolismo , Proteínas/química , Ratas , Ratas Wistar , Cráneo/anomalías
8.
Bone ; 69: 154-64, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25263524

RESUMEN

Cementum extracellular matrix is similar to other mineralized tissues; however, this unique tissue contains molecules only present in cementum. A cDNA of these molecules, cementum attachment protein (hrPTPLa/CAP) was cloned and expressed in a prokaryotic system. This molecule is an alternative splicing of protein tyrosine phosphatase-like A (PTPLa). In this study, we wanted to determine the structural and functional characteristics of this protein. Our results indicate that hrPTPLa/CAP contains a 43.2% α-helix, 8.9% ß-sheet, 2% ß-turn and 45.9% random coil secondary structure. Dynamic light scattering shows that this molecule has a size distribution of 4.8 nm and aggregates as an estimated mass of 137 kDa species. AFM characterization and FE-SEM studies indicate that this protein self-assembles into nanospheres with sizes ranging from 7.0 to 27 nm in diameter. Functional studies demonstrate that hrPTPLa/CAP promotes hydroxyapatite crystal nucleation: EDS analysis revealed that hrPTPLa/CAP-induced crystals had a 1.59 ± 0.06 Ca/P ratio. Further confirmation with MicroRaman spectrometry and TEM confirm the presence of hydroxyapatite. In vivo studies using critical-size defects in rat cranium showed that hrPTPLa/CAP promoted 73% ± 2.19% and 87% ± 1.97% new bone formation at 4 and 8 weeks respectively. Although originally identified in cementum, PTPLa/CAP is very effective at inducing bone repair and healing and therefore this novel molecule has a great potential to be used for mineralized tissue bioengineering and tissue regeneration.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Durapatita/metabolismo , Proteínas Tirosina Fosfatasas/química , Proteínas Tirosina Fosfatasas/farmacología , Animales , Dicroismo Circular , Humanos , Técnicas In Vitro , Masculino , Microscopía de Fuerza Atómica , Microscopía Electrónica , Nanosferas , Conformación Proteica , Ratas , Ratas Wistar , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacología
9.
J Clin Periodontol ; 40(1): 73-81, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23137193

RESUMEN

AIMS: To characterize the mineralized tissue formed constitutively in the supracalvarial region of scid mice by a primitive stem cell population (hOMSC) derived from the lamina propria of the human oral mucosa and gingiva. MATERIAL AND METHODS: Fibrin-hOMSC constructs were cultured for 14 days at which time point they were analysed for the expression of osteoblastic/cementoblastic markers and implanted between the skin and calvaria bones into scid mice. After 8 weeks, the animals were sacrificed and the implantation sites analysed. RESULTS: Two-week-old cultures of fibrin-hOMSC constructs expressed osteogenic/cementogenic markers at the gene level. Macroscopic and radiographic examinations revealed mineralized masses at the implantation sites of fibrin-hOMSC constructs. Histology, histochemistry and immunofluorescence showed mineralized masses consisting of avascular cellular and acellular matrices that stained positively for collagen, Ca, cementum attachment protein, cementum protein 1, bone sialoprotein, alkaline phosphatase, osteocalcin, amelogenin and ameloblastin. Positive anti-human nuclear antigen indicated the human origin of the cells. Atomic force microscopy depicted long prismatic structures organized in lamellar aggregates. CONCLUSIONS: Within the limitation of this study, the results indicate for the first time that fibrin-hOMSC constructs are endowed with the constitutive capacity to develop into mineralized tissues that exhibit certain similarities to cementum and bone.


Asunto(s)
Regeneración Ósea , Cemento Dental/fisiología , Encía/citología , Mucosa Bucal/citología , Células Madre , Fosfatasa Alcalina/biosíntesis , Amelogenina/biosíntesis , Animales , Colágeno/biosíntesis , Cemento Dental/metabolismo , Fibrina , Humanos , Sialoproteína de Unión a Integrina/biosíntesis , Ratones , Ratones SCID , Osteocalcina/biosíntesis , Proteínas Tirosina Fosfatasas/biosíntesis , Proteínas/metabolismo , Regeneración , Trasplante de Células Madre
10.
Eur J Pharmacol ; 698(1-3): 220-7, 2013 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-23142371

RESUMEN

Endomorphin-1 (EM-1) and endomorphin-2 (EM-2) are two endogenous tetrapeptides with very high affinities for the µ-opioid receptor. Until recently, the precise neuroanatomical localization of the binding sites for these peptides was unknown. However, the recent synthesis of tritiated forms of these molecules has permitted these binding sites to be analysed with a very high degree of neuroanatomical specificity. Preliminary studies demonstrated a superior binding profile for EM-2, with less non-specific binding than EM-1. As the endogenous cannabinoid and opioid systems interact at several levels, we investigated how deletion of the CNR1 gene, which encodes the cannabinoid receptor 1 (CB(1)R) protein, affects the brain distribution of EM-2 binding sites. Our results revealed no differences in the average density of EM-2 binding sites in CB(1) receptor knockout (CB(1)R KO) and WT mice. However, when both hemispheres were analysed separately, we detected specific alterations in the distribution of EM-2 binding sites in the right hemisphere of CB(1)R KO mice. While, the density of EM-2 binding sites in CB(1)R KO mice was higher in the CA3 hippocampal field and in the pontine tegmental nuclei, it was lower in the superior colliculus and ventral tegmental area than in WT controls. No differences were observed in the left hemisphere for any of the regions analysed. For the first time these findings demonstrate a lateralization effect on cerebral opioid binding sites that may be mediated by the central cannabinoid system.


Asunto(s)
Cerebro/metabolismo , Eliminación de Gen , Oligopéptidos/química , Oligopéptidos/metabolismo , Receptor Cannabinoide CB1/deficiencia , Receptor Cannabinoide CB1/genética , Animales , Sitios de Unión , Masculino , Ratones
11.
Mol Imaging Biol ; 13(3): 411-415, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20680479

RESUMEN

PURPOSE: To analyze brain metabolic response to acute cocaine in male and female Wistar rats with or without a history of cannabinoid exposure during periadolescence. PROCEDURES: The synthetic cannabinoid agonist CP 55,940 (CP) or its vehicle (VH), were administered to male and female rats during periadolescence. When these animals reached adulthood, saline and cocaine-induced changes in 2-deoxy-2-[¹8F]fluoro-D-: glucose (FDG) uptake were studied by positron emission tomography. RESULTS: The baseline (post-saline) metabolism in the septal nuclei was higher in CP-females than in VH-females, although septal metabolism was lower in CP-females after cocaine, reaching similar values to those of VH-females at baseline. Cocaine did not affect metabolism in VH-females. Periadolescent cannabinoid treatment did not influence baseline metabolism in males although cocaine reduced the FDG uptake in the dorsal striatum of males that received the VH but not CP. CONCLUSIONS: These results suggest that cannabinoids during periadolescence modify baseline and cocaine-evoked brain metabolism in a sex-dependent manner. In the case of CP-females, the involvement of septal metabolic alterations in their susceptibility to the rewarding effects of cocaine should be further investigated.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Cannabinoides/administración & dosificación , Cannabinoides/farmacología , Cocaína/administración & dosificación , Cocaína/farmacología , Envejecimiento/efectos de los fármacos , Animales , Femenino , Imagen por Resonancia Magnética , Masculino , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Ratas , Ratas Wistar , Núcleos Septales/efectos de los fármacos , Núcleos Septales/metabolismo
12.
Eur Neuropsychopharmacol ; 20(12): 895-906, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20655181

RESUMEN

In a previous work, we have shown that chronic administration of the cannabinoid agonist CP 55,940 (CP) during periadolescence increases cocaine self-administration in adult female rats, while it produces no such effect in males (Higuera-Matas et al., 2008). To extend these findings, we have analysed here the brains of the rats used as subjects in this previous work to evaluate the impact of the interaction between CP exposure and cocaine self-administration on dopaminergic parameters. We evaluated the levels of the dopamine transporter (DAT), and the D1- (D1R) and D2-type (D2R) dopaminergic receptors, as well as tyrosine hydroxylase (TH) mRNA in dopaminergic areas of the adult, cocaine self-administered, rat brain that had been chronically exposed to CP or vehicle (VH) during periadolescence. Control groups with CP/VH exposure and no self-administration experience were also included. In adult females, CP administration induced an up-regulation of DAT in the caudate-putamen that was maintained after cocaine self-administration. In males, CP induced an increase in the D1Rs content in the nucleus accumbens shell, which was not evident after cocaine self-administration. CP also reduced the expression of D2Rs in CA1 irrespective of sex. Finally, an increase in D1Rs was observed in the substantia nigra following cocaine self-administration. These findings suggest that a dopaminergic component modulated by cannabinoids may underlie the enhanced cocaine self-administration previously observed in adult female rats.


Asunto(s)
Cannabinoides/administración & dosificación , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/fisiología , Dopamina/fisiología , Hipocampo/efectos de los fármacos , Hipocampo/fisiología , Factores de Edad , Animales , Animales Recién Nacidos , Cannabinoides/efectos adversos , Cuerpo Estriado/metabolismo , Ciclohexanoles/administración & dosificación , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/fisiología , Femenino , Hipocampo/metabolismo , Masculino , Ratas , Ratas Wistar , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D1/fisiología , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D2/fisiología , Factores Sexuales
13.
Neuropharmacology ; 55(5): 771-9, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18634806

RESUMEN

Although dopamine and glutamate transmission has been implicated in cocaine dependence, the effects of the extinction of cocaine self-administration on protein transporters in both of these neurotransmitter systems remain unknown. We have used a yoked-box procedure to simultaneously test rats in triads, one rat that actively self-administered cocaine (CONT), while the other two received yoked injections of either cocaine (NON-CONT) or saline (SALINE). The brains in each triad were removed and processed for quantitative autoradiography immediately after the last session of cocaine self-administration (Day 0), or after 1, 5, or 10 days of extinction, and excitatory amino acid transporters (EAATs) and dopamine transporter (DAT) binding was examined. When compared to NON-CONT and SALINE animals, binding of radioligand to EAATs was significantly lower in the hippocampal CA1 field and the cerebellar cortex of CONT rats on Day 0, although it was significantly higher after 1 day of extinction in the infralimbic cortex. No differences in EAAT binding were observed after 5 or 10 days of extinction in any of the brain regions analyzed. In contrast and at all the time points of extinction, binding to DAT was significantly enhanced in CONT animals when compared to SALINE and NON-CONT rats in different forebrain and mesencephalic regions, including the nucleus accumbens, ventral tegmental area or caudate putamen. These results suggest that changes in protein transporter binding after cocaine self-administration and extinction are transient for EAAT while they are more enduring for DAT, and that they depend on the type of access to cocaine.


Asunto(s)
Sistema de Transporte de Aminoácidos X-AG/metabolismo , Cocaína/farmacología , Condicionamiento Operante/efectos de los fármacos , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Inhibidores de Captación de Dopamina/farmacología , Extinción Psicológica/fisiología , Animales , Ácido Aspártico/farmacología , Autorradiografía , Conducta Animal/efectos de los fármacos , Cocaína/administración & dosificación , Cocaína/análogos & derivados , Extinción Psicológica/efectos de los fármacos , Masculino , Análisis Multivariante , Unión Proteica/efectos de los fármacos , Distribución Aleatoria , Ratas , Ratas Endogámicas Lew , Refuerzo en Psicología , Autoadministración , Factores de Tiempo , Tritio/metabolismo
14.
Rev. mex. anestesiol ; 15(2): 62-8, abr.-jun. 1992. tab
Artículo en Español | LILACS | ID: lil-118486

RESUMEN

Se estudiaron 40 pacientes de ambos sexos, los cuales fueron divididos aleatoriamente en 2 grupos de 20 cada uno. Todos los pacientes fueron sometidos a diferentes procedimientos de cirugía mayor bajo anestesia general o regional. Se calculó el volumen sanguíneo de los pacientes, y se cuantificó la hemorragia y el porciento del volumen sanguíneo perdido en el transoperatorio. En un grupo se usó dextrán 40 y en otro pentalmidón como parte del régimen de líquidos para restituir la volemia. Se midieron los TP, TPT y proteínas totales antes de iniciar la administración de los expansores del plasma y a las 12, 24 y 36 horas posteriores al uso de dichos coloides, así como el 5o. día o el día de alta de los pacientes. Se tipificó la sangre, se calculó la presión oncótica, y se cuantificaron las plaquetas en los mismos tiempos. La prueba de t para muestras independientes mostró que el pentalmidón mantiene una presión oncótica significativamente mayor que la que produce el dextrán 40 (P<0.02 a P<0.001). No se encontraron diferencias significativas entre ambos grupos en los TP, TPT y cuenta de plaquetas (P>0.02). No se obserbaron cambios en la tipificació de la sangre.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Recuento de Plaquetas , Sangre , Sustitutos del Plasma , Anestesia General , Pérdida de Sangre Quirúrgica , Presión Sanguínea , Pruebas de Coagulación Sanguínea , Volumen Sanguíneo
15.
Rev. argent. anestesiol ; 48(4): 232-4, oct.-dic. 1990. tab, ilus
Artículo en Español | LILACS | ID: lil-101291
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