Fever induction pathways: evidence from responses to systemic or local cytokine formation

Abstract The immune and central nervous systems are functionally connected and interacting. The concept that the immune signaling to the brain which induces fever during infection and inflammation is mediated by circulating cytokines has been traditionally accepted. Administration of bacterial lipopolysaccharide (LPS) induces the appearance of a sotermed cytokine cascade in the circulation more or less concomitantly to the developing febrile response. Also, LPS-like fever can be induced by systemic administration of key cytokines (IL-1ß, TNF-a, and others). However, anti-cytokine strategies against IL-1ß or TNFa along with systemic injections of LPS frequently lead to attenuation of the later stages of the febrile response but not of the initial phase of fever, indicating that cytokines are rather involved in the maintenance than in the early induction of fever. Within the last years experimental evidence has accumulated indicating the existence of neural transport pathways of immune signals to the brain. Because subdiaphragmatic vagotomy prevents or attenuates fever in response to intraperitoneal or intravenous injections of LPS, a role for vagal afferent nerve fibers in fever induction has been proposed. Also other sensory nerves may participate in the manifestation of febrile responses under certain experimental conditions. Thus, injection of a small dose of LPS into an artificial subcutaneous chamber results in fever and formation of cytokines within the inflamed tissue around the site of injection. This febrile response can be blocked in part by injection of a local anesthetic into the subcutaneous chamber, indicating a participation of cutaneous afferent nerve signals in the manifestation of fever in this model. In conclusion, humoral signals and an inflammatory stimulation of afferent sensory nerves can participate in the generation and maintenance of a febrile response. Key words Humoral signals and fever: the relation between circulating cytokines and the febrile response After a challenge with an infectious or inflammatory stimulus somewhere at the periphery of the body a number of responses are generated within the CNS. These brainmediated signs of illness include changes in neuroendocrine activities including activation of the hypothalamic-pituitary-adrenal (HPA) axis, anorexia and adipsia, changes i

Levantamento e avaliação da literatura econômica sobre o BNDES

Projeto executado com o apoio financeiro do Banco Nacional do Desenvolvimento Econômico e Social (BNDES), por meio de refinanciamento não reembolsável com recursos do Fundo de Estruturação de Projetos do BNDES (FEP): Pesquisa Científica nº 03/2011 - FEP/BNDES Literatura Econômica.Créditos : Pesquisadores: Anne Hanley, Júlio Manuel Pires, Maurício Jorge Pinto de Souza, Renato Leite Marcondes, Rosane Nunes de Faria, Sérgio Naruhiko SakuraiA nossa pesquisa objetiva realizar uma sistematização e avaliação da literatura econômica produzida a respeito do BNDES desde o seu início. Para tanto, na primeira parte do projeto, a qual se refere esse relatório, realizamos uma revisão dos argumentos teóricos para a atuação de um banco de desenvolvimento, bem como, uma discussão da perspectiva histórica associada à criação e evolução dos bancos de desenvolvimento, em especial do BNDES. Nas próximas etapas da pesquisa, tal arcabouço teórico e histórico possibilitará avaliar não apenas o conjunto da produção por meio de uma análise bibliométrica, mas também os argumentos e evidências utilizados nos trabalhos acadêmicos de maior impacto que analisam o papel do BNDES

Self–Organizing Maps #

BioChem Press 21