963 resultados para Cerebral ischemia -- Animal models
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IMPORTANCE There is a high prevalence of obesity in psychiatric patients, possibly leading to metabolic complications and reducing life expectancy. The CREB-regulated transcription coactivator 1 (CRTC1) gene is involved in energy balance and obesity in animal models, but its role in human obesity is unknown. OBJECTIVE To determine whether polymorphisms within the CRTC1 gene are associated with adiposity markers in psychiatric patients and the general population. DESIGN, SETTING, AND PARTICIPANTS Retrospective and prospective data analysis and population-based samples at Lausanne and Geneva university hospitals in Switzerland and a private clinic in Lausanne, Switzerland. The effect of 3 CRTC1 polymorphisms on body mass index (BMI) and/or fat mass was investigated in a discovery cohort of psychiatric outpatients taking weight gain-inducing psychotropic drugs (sample 1, n = 152). The CRTC1 variant that was significantly associated with BMI and survived Bonferroni corrections for multiple comparison was then replicated in 2 independent psychiatric samples (sample 2, n = 174 and sample 3, n = 118) and 2 white population-based samples (sample 4, n = 5338 and sample 5, n = 123 865). INTERVENTION Noninterventional studies. MAIN OUTCOME AND MEASURE Difference in BMI and/or fat mass between CRTC1 genotype groups. RESULTS Among the CRTC1 variants tested in the first psychiatric sample, only rs3746266A>G was associated with BMI (Padjusted = .003). In the 3 psychiatric samples, carriers of the rs3746266 G allele had a lower BMI than noncarriers (AA genotype) (sample 1, P = .001; sample 2, P = .05; and sample 3, P = .0003). In the combined analysis, excluding patients taking other weight gain-inducing drugs, G allele carriers (n = 98) had a 1.81-kg/m2 lower BMI than noncarriers (n = 226; P < .0001). The strongest association was observed in women younger than 45 years, with a 3.87-kg/m2 lower BMI in G allele carriers (n = 25) compared with noncarriers (n = 48; P < .0001), explaining 9% of BMI variance. In the population-based samples, the T allele of rs6510997C>T (a proxy of the rs3746266 G allele; r2 = 0.7) was associated with lower BMI (sample 5, n = 123 865; P = .01) and fat mass (sample 4, n = 5338; P = .03). The strongest association with fat mass was observed in premenopausal women (n = 1192; P = .02). CONCLUSIONS AND RELEVANCE These findings suggest that CRTC1 contributes to the genetics of human obesity in psychiatric patients and the general population. Identification of high-risk subjects could contribute to a better individualization of the pharmacological treatment in psychiatry.
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Obesity is an increasingly serious health problem, and is highly associated with insulin-resistance and dyslipidemia. The mechanisms involved in the development of this disorder are still poorly understood, although significant progress has been recently made in the elucidation of their molecular basis. The major causes leading to obesity are defects in the regulation of fat metabolism. Several mutations identified in different animal models have unveiled the roles of a number of genes in the regulation of energy balance. These dicoveries, together with the fact that some of these mutations have been found in humans, have lead to the conclusion that obesity is due to nutritional or environmental factors, but also involves genetic factors. A number of important peripheric factors participate in the regulation processes, such as the adipocyte-specific hormone leptin, and the nuclear homone receptors PPARs. A general scheme can now be drawn which includes some key factors and their respective interactions.
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For the development of vaccine strategies to generate efficient protection against chronic infections such as parasitic diseases, and more precisely schistosomiasis, controlling pathology could be more relevant than controlling the infection itself. Such strategies, motivated by the need for a cost-effective complement to existing control measures, should focus on parasite molecules involved in fecundity, because in metazoan parasite infections pathology is usually linked to the output of viable eggs. In numerous animal models, vaccination with glutathione S-transferases of 28kDa has been shown to generate an immune response strongly limiting the worm fecundity, in addition to the reduction of the parasite burden. Recent data on acquired immunity directed to 28GST in infected human populations, and new development to draw adapted vaccine formulations, are presented.
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Background: Inhibition of the c-Jun N-terminal kinase (JNK) pathway by the TAT-coupled peptide XG-102 (formerly D-JNKI1) induces strong neuroprotection in ischemic stroke in rodents. We investigated the effect of JNK inhibition in intracerebral hemorrhage (ICH). Methods: Three hours after induction of ICH by intrastriatal collagenase injection in mice, the animals received an intravenous injection of 100 mu g/kg of XG-102. The neurological outcome was assessed daily and the mice were sacrificed at 6 h, 1, 2 or 5 days after ICH. Results: XG-102 administration significantly improved the neurological outcome at 1 day (p < 0.01). The lesion volume was significantly decreased after 2 days (29 +/- 11 vs. 39 +/- 5 mm(3) in vehicle-treated animals, p < 0.05). There was also a decreased hemispheric swelling (14 +/- 13 vs. 26 +/- 9% in vehicle-treated animals, p < 0.05) correlating with increased aquaporin 4 expression. Conclusions: XG-102 attenuates cerebral edema in ICH and functional impairment at early time points. The beneficial effects observed with XG-102 in ICH, as well as in ischemic stroke, open the possibility to rapidly treat stroke patients before imaging, thereby saving precious time.
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Glut-2 is a low-affinity transporter present in the plasma membrane of pancreatic beta-cells, hepatocytes and intestine and kidney absorptive epithelial cells of mice. In beta-cells, Glut-2 has been proposed to be active in the control of glucose-stimulated insulin secretion (GSIS; ref. 2), and its expression is strongly reduced in glucose-unresponsive islets from different animal models of diabetes. However, recent investigations have yielded conflicting data on the possible role of Glut-2 in GSIS. Whereas some reports have supported a specific role for Glut-2 (refs 5,6), others have suggested that GSIS could proceed normally even in the presence of low or almost undetectable levels of this transporter. Here we show that homozygous, but not heterozygous, mice deficient in Glut-2 are hyperglycaemic and relatively hypo-insulinaemic and have elevated plasma levels of glucagon, free fatty acids and beta-hydroxybutyrate. In vivo, their glucose tolerance is abnormal. In vitro, beta-cells display loss of control of insulin gene expression by glucose and impaired GSIS with a loss of first phase but preserved second phase of secretion, while the secretory response to non-glucidic nutrients or to D-glyceraldehyde is normal. This is accompanied by alterations in the postnatal development of pancreatic islets, evidenced by an inversion of the alpha- to beta-cell ratio. Glut-2 is thus required to maintain normal glucose homeostasis and normal function and development of the endocrine pancreas. Its absence leads to symptoms characteristic of non-insulin-dependent diabetes mellitus.
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Sleep disorders are very prevalent and represent an emerging worldwide epidemic. However, research into the molecular genetics of sleep disorders remains surprisingly one of the least active fields. Nevertheless, rapid progress is being made in several prototypical disorders, leading recently to the identification of the molecular pathways underlying narcolepsy and familial advanced sleep-phase syndrome. Since the first reports of spontaneous and induced loss-of-function mutations leading to hypocretin deficiency in human and animal models of narcolepsy, the role of this novel neurotransmission pathway in sleep and several other behaviors has gained extensive interest. Also, very recent studies using an animal model of familial advanced sleep-phase syndrome shed new light on the regulation of circadian rhythms.
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Flow cytometry has been used as a powerful technique for studying cell surface antigen expression as well as intracellular molecules. Its capability of analyzing multiple parameters simultaneously on a single cell has allowed identification and studies of functional cell subsets within heterogeneous populations. In this respect, several techniques have been developed during the past few years to study cytokine-producing cells by flow cytometry in humans and several animal models.
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Applications of flow cytometry to clinical and experimental hematopoietic stem cell transplantation (HSCT) are discussed in this review covering the following topics: diagnosis and classification of lymphohematologic disorders, quantitation of hematopoietic progenitors in the graft, lymphohematopoietic reconstitution following HSCT and animal models of human HSCT. At the end, the utilization of flow cytometry in clinical HSCT by Brazilian transplant centers is briefly reviewed.
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Resum: El pemfigoid ampul•lar és una malaltia cutània autoimmune. La majoria dels pacients presenten autoanticossos contra proteïnes de la membrana basal de la pell, concretament en contra de la col·làgena XVII, específicament envers el epítop immunodominant, l’NC16A. La patogenicitat dels anticossos ha estat demostrada mitjançant experiments in vitro i in vivo. L’escassa homologia existent entre l’NC16A i el seu homòleg murí (NC14A), ha dificultat l’el·laboració de models animals d’aquesta malaltia. En aquest treball demostrem que el sèrum de pacients amb pemfigoid ampul•lar produeix separació dermo-epidèrmica en pell de ratolí humanitzada obtinguda a partir de cèl•lules mare humanes del provinents fol·licle pil·lós
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Excitotoxic insults induce c-Jun N-terminal kinase (JNK) activation, which leads to neuronal death and contributes to many neurological conditions such as cerebral ischemia and neurodegenerative disorders. The action of JNK can be inhibited by the D-retro-inverso form of JNK inhibitor peptide (D-JNKI1), which totally prevents death induced by N-methyl-D-aspartate (NMDA) in vitro and strongly protects against different in vivo paradigms of excitotoxicity. To obtain optimal neuroprotection, it is imperative to elucidate the prosurvival action of D-JNKI1 and the death pathways that it inhibits. In cortical neuronal cultures, we first investigate the pathways by which NMDA induces JNK activation and show a rapid and selective phosphorylation of mitogen-activated protein kinase kinase 7 (MKK7), whereas the only other known JNK activator, mitogen-activated protein kinase kinase 4 (MKK4), was unaffected. We then analyze the action of D-JNKI1 on four JNK targets containing a JNK-binding domain: MAPK-activating death domain-containing protein/differentially expressed in normal and neoplastic cells (MADD/DENN), MKK7, MKK4 and JNK-interacting protein-1 (IB1/JIP-1).
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The studies of rare genetic defects, the preliminary results of population-based studies, being validated by the experimental immunocompromised animal models and the current observations accumulated in immunocompromised patients with mycobacterial diseases provide us with insights into the importance of the macrophage activation pathway in controlling human infection with pathogenic and non pathogenic intracellular multiplying mycobacteria. Initial cytokine production by infected macrophages and/or dendritic cells could be crucial in the overall regulation of self cure, acquired protection or immunopathological sequelae expressing the disease. Knowledge of molecular and genetic cross-talks between phagocytic and specialized antigen presenting cells and different mycobacterial products associated with persistence or replication of the intracellular bacteria, could provide further informations on the global immune regulation of the early host responses to infection and the following events. It seems likely that the development of mycobacterial infections in humans will turn out to be as much dependent on the genetic make up of the host as or the virulence of the bacteria.
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CD8+ T cells have been implicated as critical effector cells in protection against the pre-erythrocytic stage of malaria in mice and humans following irradiated sporozoite immunization. Immunization experiments in animal models by several investigators have suggested different strategies for vaccination against malaria and many of the targets from liver stage malaria antigens have been shown to be immunogenic and to protect mice from the sporozoite challenge. Several prime/boost protocols with replicating vectors, such as vaccinia/influenza, with non-replicating vectors, such as recombinant particles derived from yeast transposon (Ty-particles) and modified vaccinia virus Ankara, and DNA, significantly enhanced CD8+ T cell immunogenicity and also the protective efficacy against the circumsporosoite protein of Plasmodium berghei and P. yeti. Based on these experimental results the development of a CD8+ T cell inducing vaccine has moved forward from epitope identification to planning stages of safety and immunogenicity trials of candidate vaccines.
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There are several data in the literature indicating a great variety of pharmacological activities of Curcuma longa L. (Zingiberaceae), which exhibit anti-inflammatory, anti-human immunodeficiency virus, anti-bacteria, antioxidant effects and nematocidal activities. Curcumin is a major component in Curcuma longa L., being responsible for its biological actions. Other extracts of this plant has been showing potency too. In vitro, curcumin exhibits anti-parasitic, antispasmodic, anti-inflammatory and gastrointestinal effects; and also inhibits carcinogenesis and cancer growth. In vivo, there are experiments showing the anti-parasitic, anti-inflammatory potency of curcumin and extracts of C. longa L. by parenteral and oral application in animal models. In this present work we make an overview of the pharmacological activities of C. longa L., showing its importance.
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El sistema nerviós central (SNC) i el sistema immunitari (SI) estan estretament connectats. Es produeixen nombroses alteracions en el sistema immunitari després de la isquèmia i la inflamació es reconeix com una de les principals causes de la progressió de la lesió isquèmica. És molt important determinar el paper de les diferents cèl•lules implicades en la resposta immunitària i inflamatòria després de la isquèmia i el perfil de citocines que s’alliberen. A partir de l’estudi de les diferents poblacions de leucòcits en sang circulant després de la isquèmia, hem determinat que la subpoblació de monòcits (CD43high/CD11bhigh) augmenta a 48h de manera proporcional al volum d’infart. Aquesta població està formada per dos subtipus descrits de monòcits, els no clàssics (CD43high/Ly6C-) i els intermedis (CD43high/Ly6Cdim), i sembla expressar un perfil de citocines anti-inflamatòries així com una major capacitat fagocítica. Per altra banda, observem la presència de CD43 en el cervell i la seva degradació a 4 dies després de la isquèmia. També s’observa l’aparició de la fracció soluble del CD43 en el parènquima cerebral després del trencament de la barrera hematoencefàlica. Addicionalment, hem estudiat com s’alteren els canvis a nivell immunològic en ratolins deficients en CD69 i hem observat una pitjor progressió del volum d’infart en els animals CD69KO. A més a més hem volgut esbrinar el paper dels limfòcits utilitzant ratolins RAG (-/-) que tenen infarts més petits que els WT, però quan aquests careixen de CD69, tenen infarts significativament més grans. En l’estudi del procés inflamatori en la isquèmica, hem treballat amb ratolins deficient en ApoE i IL10. Pel que fa als ratolins ApoE (-/-), observem que tenen un volum d’infart més gran a les 24h i que es manté fins als 4 dies, i proposem que NFkB pot tenir un paper molt rellevant en aquest procés. Pel que fa a la IL-10, els animals deficients en aquesta citocina presenten un volum d’infart major i una expressió de citocines proinflamatòries més alt. A més a més, els ratolins IL10 KO presenten uns nivells de IL-12 més elevats de manera basal, i proposem que això és degut a la falta de la IL-10 per a inhibir la via.
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In previous studies it was shown that the recombinant molecule, r-Sm14, induces high levels of protection against Schistosoma mansoni infection in two outbred animal models and immune crossprotection against infection by Fasciola hepatica in Swiss outbred mice. r-Sm14 was derived from a living worm extract, called SE, and is being developed as the molecular basis of an anti-helminth bivalent vaccine against the two parasites, for medical and veterinary application. Present data refer to SDS-PAGE and Western Blotting analysis of four different preparations of S. mansoni adult worms focusing Sm14 identification. The extracts correspond to the initial fraction of the SE extraction process, containing products released by living worms (SEi); SE2, reextraction of adult worms in PBS; and SE of separated male and female adult worms. In all extracts it was possible to detect the component of 14 kDa, that was recognized by specific anti-rSm14 antibody raised in rabbits.