67 resultados para Masaryk, T. G. (Tomáš Garrigue), 1850-1937
Resumo:
The idea that a receptor can produce signalling without agonist intervention and that several antagonists can be 'active' in repressing such spontaneous activity is contained in the concept of ligand-induced conformational changes. Yet, this idea was neglected by pharmacologists for many years. In this article, we review the events that brought inverse agonism and constitutive activity to general attention and made this phenomenon a topic of current research. We also suggest a classification of antagonists based on the cooperativity that links their primary site of interaction with other functional domains of the receptor.
Resumo:
Switzerland appears to be a privileged place to investigate the urban political ecology of tap water because of the specificities of its political culture and organization and the relative abundance of drinking water in the country. In this paper, we refer to a Foucauldian theorization of power that is increasingly employed in the social sciences, including in human geography and political ecology. We also implement a Foucauldian methodology. In particular, we propose an archaeo-genealogical analysis of discourse to apprehend the links between urban water and the forms of governmentality in Switzerland between 1850 and 1950. Results show that two forms of governmentality, namely biopower and neoliberal governmentality, were present in the water sector in the selected period. Nonetheless, they deviate from the models proposed by Foucault, as their periodization and the classification of the technologies of power related to them prove to be much more blurred than Foucault's work, mainly based on France, might have suggested.
Le risque fracturaire, comment prédire le risque de fracture ostéoporotique chez le patient âgé?
Resumo:
Decreasing perinatal morbidity and mortality is one of the main goals of obstetrics. Prognosis of preterm births depends on gestational age and birthweight. Multidisciplinary management is discussed with the parents according to these two parameters. In other circumstances, a suspected macrosomy will influence the management of the last weeks of pregnancy. Induction of labor or Cesarean delivery will be considered to avoid shoulder dystocia, brachial plexus injury or perinatal asphyxia. Birthweight needs to be estimated with accuracy, and this article describes the efficiency of various ultrasound weight estimation formulae for small and large fetuses.
Resumo:
Since the first reports of induction of adipose-derived stem cells (ASC) into neuronal and glial cell phenotypes, expectations have increased regarding their use in tissue engineering applications for nerve repair. Cell adhesion to extracellular matrix (ECM) is a basic feature of survival, differentiation, and migration of Schwann cells (SC) during nerve regeneration, and fibronectin and laminin are two key molecules of this process. Interaction between ECM and SC-like differentiated ASC (dASC) could potentially improve the neurotrophic potential of the stem cells. We have investigated the effect of ECM molecules on SC-like dASC in terms of proliferation, adhesion, and cell viability. Fibronectin and laminin did not affect the proliferation of dASC when compared with cell adherent tissue culture plastic, but significantly improved viability and cell attachment when dASC were exposed to apoptotic conditions. To assess the influence of the ECM molecules on dASC neurotrophic activity, dASC were seeded onto ECM-coated culture inserts suspended above dorsal root ganglia (DRG) sensory neurons. Neurite outgrowth of DRG neurons was enhanced when dASC were seeded on fibronectin and laminin when compared with controls. When DRG neurons and dASC were in direct contact on the various surfaces there was significantly enhanced neurite outgrowth and coculture with laminin-conditioned dASC produced the longest neurites. Compared with primary SCs, dASC grown on laminin produced similar levels of neurite outgrowth in the culture insert experiments but neurite length was shorter in the direct contact groups. Anti β1 integrin blocking antibody could inhibit baseline and dASC evoked neurite elongation but had no effect on outgrowth mediated by laminin-conditioned dASC. ECM molecules had no effect on the levels of nerve growth factor and brain-derived neurotrophic factor secretion from dASC. The results of the study suggest that ECM molecules can significantly improve the potential of dASC for nerve regeneration.
Resumo:
There is evidence of associations between social functioning and theory of mind performance and between social functioning and negative symptoms in chronic psychosis. This study investigates these associations in those with first episode psychosis who are unaffected by factors related to long-term mental illness. Our first hypothesis states that there is an association between theory of mind and social functioning. The second hypothesis states that there is no association between symptoms of psychosis and social functioning. Methods. Fifty-two individuals with first episode psychosis were assessed for social functioning, theory of mind ability (using the Hinting test with verbal stimuli and the Visual Cartoon test with pictorial stimuli), and symptoms of psychosis. Multivariable logistic regression was used to examine associations. Results. Social functioning and theory of mind were associated when measured by the Hinting test (OR 1.70, 95% CI 1.08, 2.66), but not with the Visual Cartoon test (ToM jokes OR 0.61, 95% CI 0.15, 2.53). There was no association between social functioning and symptoms (psychotic symptoms; OR 0.95, 95% CI 0.81, 1.12; selected negative symptoms; OR 1.33, 95% CI 0.78, 2.25). Conclusions. Theory of mind assessed by verbal stimuli is associated with social functioning in a population with first episode psychosis. These findings may be related to language disorders in psychosis.
Resumo:
In response to pathological stresses, the heart undergoes a remodelling process associated with cardiac hypertrophy. Since sustained hypertrophy can progress to heart failure, there is an intense investigation about the intracellular signalling pathways that control cardiomyocyte growth. Accumulating evidence has demonstrated that most stimuli known to initiate pathological changes associated with the development of cardiac hypertrophy activate G protein-coupled receptors (GPCRs) including the αl-adrenergic- (αl-AR), Angiotensin II- (AT-R) and endothelin-1- (ET-R) receptors. In this context, we have previously identified a cardiac scaffolding protein, called AKAP-Lbc (Α-kinase anchoring protein), with an intrinsic Rho specific guanine nucleotide exchange factor activity, that plays a key role in integrating and transducing hypertrophic signals initiated by these GPCRs (Appert-Collin, Cotecchia et al. 2007). Activated RhoA controls the transcriptional activation of genes involved in cardiomyocyte hypertrophy through signalling pathways that remain to be characterized. Here, we identified the nuclear factor-Kappa Β (NF-κΒ) activating kinase ΙΚΚβ as a novel AKAP-Lbc interacting protein. This raises the hypothesis that AKAP-Lbc might promote cardiomyocyte growth by maintaining a signalling complex that promotes the activation of the pro-hypertrophic transcription factor NF-κΒ. In fact, the activation of NF- κΒ-dependent transcription has been detected in numerous disease contexts, including hypertrophy, ischemia/reperfusion injury, myocardial infarction, allograft rejection, myocarditis, apoptosis, and more (Hall, Hasday et al. 2006). While it is known by more than a decade that NF-κΒ is a critical mediator of cardiac hypertrophy, it is currently poorly understood how pro-hypertrophic signals controlling NF-κΒ transcriptional activity are integrated and coordinated within cardiomyocytes. In this study, we show that AKAP-Lbc and ΙΚΚβ form a transduction complex in cardiomyocytes that couples activation of αl-ARs to NF-κB-mediated transcriptional reprogramming events associated with cardiomyocyte hypertrophy. In particular, we can show that activation of ΙΚΚβ within the AKAP-Lbc complex promotes NF-κB-dependent production of interleukine-6 (IL-6), which, in turn, enhances foetal gene expression. These findings indicate that the AKAP-Lbc/ΙΚΚβ complex is critical for selectively directing catecholamine signals to the induction of cardiomyocyte hypertrophy.