40 research outputs found
Religião, literatura e a dinâmica colonial na África
Este artigo analisa os elementos de religiosidade e colonização nos romances pós-coloniais da literatura africana, com o intuito de refletir sobre os efeitos da aproximação da Europa cristã das populações tradicionais africanas, e as práticas de representação literária desse encontro secular. Como corpus de investigação comparada, foram analisadas as obras O Outro Pé da Sereia (2006) e Um rio chamado tempo, uma casa chamada terra (2003) de Mia Couto, A Gloriosa Família: o tempo dos flamengos (1999) de Pepetela e A flecha de Deus (2011) de Chinua Achebe. Os textos apresentam interpretações particulares sobre o encontro cultural histórico decorrente da colonização europeia a partir de concepções ficcionais atuais sobre o processo de hibridismo cultural e sincretismo religioso das nações africanas por meio da releitura da história
Moderate exercise changes synaptic and cytoskeletal proteins in motor regions of the rat brain
Physical exercise is known to enhance brain function in several aspects. We evaluated the acute effects of a moderate forced exercise protocol on synaptic proteins, namely synapsin 1 (SYN) and synaptophysin (SYP), and structural proteins (neurofilaments, NFs) in rat brain regions related to motor function and often affected by neurodegenerative disorders. Immunohistochemistry, Western blotting and real-time PCR were used to analyze the expression of those proteins after 3, 7 and 15 days of exercise (EX3, EX7 and EX15). In the cerebellum, increase of SYN was observed at EX7 and EX15 and of NF68 at EX3. In the substantia nigra, increases of protein levels were observed for NF68 and NF160 at EX3. In the striatum, there was an increase of SYN at EX3 and EX7, of SYP at EX7 and of NF68 at EX3. In the cortex, decreased levels of NF68 and NF160 were observed at EX3, followed by an increase of NF68 at EX15. In the reticular formation, all NF proteins were increased at EX15. The mRNA data for each time-point and region also revealed significant exercise-related changes of SYN, SYP and NF expression. These results suggest that moderate physical exercise modulates synaptic and structural proteins in motor brain areas, which may play an important role in the exercise-dependent brain plasticity. (C) 2010 Elsevier B.V. All rights reserved.FAPESPFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq (Brazil)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Tyrosine hydroxylase immunoreactivity as indicator of sympathetic activity: simultaneous evaluation in different tissues of hypertensive rats
Burgi K, Cavalleri MT, Alves AS, Britto LRG, Antunes VR, Michelini LC. Tyrosine hydroxylase immunoreactivity as indicator of sympathetic activity: simultaneous evaluation in different tissues of hypertensive rats. Am J Physiol Regul Integr Comp Physiol 300: R264-R271, 2011. First published December 9, 2010; doi: 10.1152/ajpregu.00687.2009.-Vasomotor control by the sympathetic nervous system presents substantial heterogeneity within different tissues, providing appropriate homeostatic responses to maintain basal/stimulated cardiovascular function both at normal and pathological conditions. The availability of a reproducible technique for simultaneous measurement of sympathetic drive to different tissues is of great interest to uncover regional patterns of sympathetic nerve activity (SNA). We propose the association of tyrosine hydroxylase immunoreactivity (THir) with image analysis to quantify norepinephrine (NE) content within nerve terminals in arteries/arterioles as a good index for regional sympathetic outflow. THir was measured in fixed arterioles of kidney, heart, and skeletal muscle of WistarKyoto rats (WKY) and spontaneously hypertensive rats (SHR) (123 +/- 2 and 181 +/- 4 mmHg, 300 +/- 8 and 352 +/- 8 beats/min, respectively). There was a differential THir distribution in both groups: higher THir was observed in the kidney and skeletal muscle (similar to 3-4-fold vs. heart arterioles) of WKY; in SHR, THir was increased in the kidney and heart (2.4- and 5.3-fold vs. WKY, respectively) with no change in the skeletal muscle arterioles. Observed THir changes were confirmed by either: 1) determination of NE content (high-performance liquid chromatography) in fresh tissues (SHR vs. WKY): +34% and +17% in kidney and heart, respectively, with no change in the skeletal muscle; 2) direct recording of renal (RSNA) and lumbar SNA (LSNA) in anesthetized rats, showing increased RSNA but unchanged LSNA in SHR vs. WKY. THir in skeletal muscle arterioles, NE content in femoral artery, and LSNA were simultaneously reduced by exercise training in the WKY group. Results indicate that THir is a valuable technique to simultaneously evaluate regional patterns of sympathetic activity.FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[06/50548-9]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[08/53961-0]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP Fundacao de Amparo a Pesquisa do Estado de Sao Paulo[07/53320-1]Conselho Nacional de Pesquisa (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Transdural motor cortex stimulation reverses neuropathic pain in rats: A profile of neuronal activation
Motor cortex stimulation (MCS) has been used to treat patients with neuropathic pain resistant to other therapeutic approaches; however, the mechanisms of pain control by MCS are still not clearly understood. We have demonstrated that MCS increases the nociceptive threshold of naive conscious rats, with opioid participation. In the present study, the effect of transdural MCS on neuropathic pain in rats subjected to chronic constriction injury of the sciatic nerve was investigated. In addition, the pattern of neuronal activation, evaluated by Fos and Zif268 immunolabel, was performed in the spinal cord and brain sites associated with the modulation of persistent pain. MCS reversed the mechanical hyperalgesia and allodynia induced by peripheral neuropathy. After stimulation, Fos immunoreactivity (Fos-IR) decreased in the dorsal horn of the spinal cord and in the ventral posterior lateral and medial nuclei of the thalamus, when compared to animals with neuropathic pain. Furthermore, the MCS increased the Fos-IR in the periaqueductal gray, the anterior cingulate cortex and the central and basolateral amygdaloid nuclei. Zif268 results were similar to those obtained for Fos, although no changes were observed for Zif268 in the anterior cingulate cortex and the central amygdaloid nucleus after MCS. The present findings suggest that MCS reverts neuropathic pain phenomena in rats, mimicking the effect observed in humans, through activation of the limbic and descending pain inhibitory systems. Further investigation of the mechanisms involved in this effect may contribute to the improvement of the clinical treatment of persistent pain. (c) 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Hospital Sirio-LibanesHospital Sirio-LibanesConselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Modulation of Adhesion Molecules Expression by Different Metalloproteases Isolated from <i>Bothrops</i> Snakes
Snake venom metalloproteinases (SVMP) are involved in local inflammatory reactions observed after snakebites. Based on domain composition, they are classified as PI (pro-domain + proteolytic domain), PII (PI + disintegrin-like domains), or PIII (PII + cysteine-rich domains). Here, we studied the role of different SVMPs domains in inducing the expression of adhesion molecules at the microcirculation of the cremaster muscle of mice. We used Jararhagin (Jar)—a PIII SVMP with intense hemorrhagic activity, and Jar-C—a Jar devoid of the catalytic domain, with no hemorrhagic activity, both isolated from B. jararaca venom and BnP-1—a weakly hemorrhagic P1 SVMP from B. neuwiedi venom. Toxins (0.5 µg) or PBS (100 µL) were injected into the scrotum of mice, and 2, 4, or 24 h later, the protein and gene expression of CD54 and CD31 in the endothelium, and integrins (CD11a and CD11b), expressed in leukocytes were evaluated. Toxins induced significant increases in CD54, CD11a, and CD11b at the initial time and a time-related increase in CD31 expression. In conclusion, our results suggest that, despite differences in hemorrhagic activities and domain composition of the SVMPs used in this study, they behave similarly to the induction of expression of adhesion molecules that promote leukocyte recruitment
Reactive adsorption of methylene blue on montmorillonite via an ESI-MS study
Catalytic and adsorptive behaviors of montmorillonite to remove methylene blue were investigated. The clay mineral showed high activity for the oxidation of methylene blue in presence of H2O2 and on removing the organic substrate through reactive adsorption as evidenced from Electrospray Ionization Mass Spectrometry (ESI-MS) data. Montmorillonite was characterized by atomic absorption, powder X-ray diffractometry, scanning electron microscopy coupled with energy dispersive spectroscopy, infra-red spectroscopy and surface area analyses. Results indicated a highly reactive surface with can be regenerated by H2O2, promoting heterogeneous catalytic reaction to oxidize organic compounds from aqueous medium without any previous treatment of the montmorillonite.Fil: Nogueira, Francisco Guilherme Esteves. Universidad Federal de Lavras; BrasilFil: Lopes, João Henrique. Universidad Federal de Lavras; BrasilFil: Silva, Adilson C.. Universidad Federal de Lavras; BrasilFil: Gonçalves, Maraisa. Universidad Federal de Lavras; BrasilFil: Anastácio, Alexandre S.. Universidad Federal de Lavras; BrasilFil: Sapag, Manuel Karim. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich"; ArgentinaFil: Alves de Oliveira, Luiz Carlos. Universidad Federal de Lavras; Brasi