862 resultados para Migratory locust.
Resumo:
Little is known about insect intestinal sugar absorption, in spite of the recent findings, and even less has been published regarding water absorption. The aim of this study was to shed light on putative transporters of water and glucose in the insect midgut Glucose and water absorptions by the anterior ventriculus of Dysdercus peruvianus midgut were determined by feeding the insects with a glucose and a non-absorbable dye solution, followed by periodical dissection of insects and analysis of ventricular contents. Glucose absorption decreases glucose/dye ratios and water absorption increases dye concentrations. Water and glucose transports are activated (water 50%, glucose 33%) by 50 mM K(2)SO(4) and are inhibited (water 46%, glucose 82%) by 0.2 mM phloretin, the inhibitor of the facilitative hexose transporter (GLUT) or are inhibited (water 45%, glucose 35%) by 0.1 mM phlorizin, the inhibitor of the Na(+)-glucose cotransporter (SGLT). The results also showed that the putative SGLT transports about two times more water relative to glucose than the putative GLUT. These results mean that D. peruvianus uses a GLUT-like transporter and an SGLT-like transporter (with K(+) instead of Na(+)) to absorb dietary glucose and water. A cDNA library from D. peruvianus midgut was screened and we found one sequence homologous to GLUT1, named DpGLUT, and another to a sodium/solute symporter, named DpSGLT. Semi-quantitative RT-PCR studies revealed that DpGLUT and DpSGLTs mRNA were expressed in the anterior midgut, where glucose and water are absorbed, but not in fat body, salivary gland and Malpighian tubules. This is the first report showing the involvement of putative GLUT and SGLT in both water and glucose midgut absorption in insects. (C) 2010 Elsevier Inc. All rights reserved.
Resumo:
Squamous cell carcinoma is a prevalent head and neck tumor with high mortality. We studied the role played by laminin alpha 1 chain peptide AG73 on migration, invasion, and protease activity of cells (OSCC) from human oral squamous cell carcinoma. Immunohistochemistry and immunofluorescence analyzed expression of laminin alpha 1 chain and MMP9 in oral squamous cells carcinoma in vivo and in vitro. Migratory activity of AG73-treated OSCC cells was investigated by monolayer wound assays and in chemotaxis chambers. AG73-induced invasion was assessed in Boyden chambers. Invasion depends on MMPs. Conditioned media from cells grown on AG73 was subjected to zymography. We searched for AG73 receptors related to these activities in OSCC cells. Immunofluorescence analyzed AG73induced colocalization of syndecan-1 and beta 1 integrin. Cells had these receptors silenced by siRNA, followed by treatment with AG73 and analysis of migration, invasion, and protease activity. Oral squamous cell carcinoma expresses laminin alpha 1 chain and MMP9. OSCC cells treated with AG73 showed increased migration, invasion, and protease activity. AG73 induced colocalization of syndecan-1 and beta 1 integrin. Knockdown of these receptors decreased AG73-dependent migration, invasion, and protease activity. Syndecan-1 and beta 1 integrin signaling downstream of AG73 regulate migration, invasion, and MMP production by OSCC cells.
Resumo:
We studied the expression pattern of cell adhesion molecules associated to transendothelial migration of leukocytes in different lung`s vascular compartments after administration of a magnetic fluid sample containing maghemite nanoparticles surface-coated with meso-2,3-dimercaptosuccinic acid. The analyses were conducted in mice 4 and 12 h after endovenous administration of the magnetic fluid in control mice. Firstly, the migratory activity of leukocytes after magnetic fluid surface-coated with meso-2,3-dimercaptosuccinic acid administration was confirmed using broncho-alveolar lavage and light microscopy. Then, the expression of cell adhesion molecules in the lung`s vascular compartments was investigated by immunofluorescence microscopy of frozen sections, using antibodies against L-selectin, P-selectin, E-selectin, macrophage antigen-1, and leukocyte function associated antigen-1. L- and P-selectin showed similar pattern of expression in the pulmonary vasculature in animals treated with magnetic fluid and in the control group. In contrast, macrophage antigen-1 and leukocyte function associated antigen-1 were found in capillary only in animals treated with magnetic fluid surface-coated with meso-2,3-dimercaptosuccinic acid administration. In addition, after magnetic fluid administration E-selectin was found in post-capillary sites. Our findings demonstrated that magnetic fluid surface-coated with meso-2,3-dimercaptosuccinic acid administration exhibits modulation effects on expression patterns of E-selectin, macrophage antigen-1, and leukocyte function associated antigen-1 in the lung`s vascular compartments. These findings are very important in a strategy to reduce the potential toxicity of magnetic fluid surface-coated with meso-2,3-dimercaptosuccinic acid administration for medical applications.
Resumo:
Fecundity and oocyte development in Salminus hilarii female brood stock were analyzed with the aim of investigating the impact of migration impediment on oogenesis. Histological analyses of the ovaries were performed in adult females caught in two different environments-the TietA(a) River (natural) and captivity-and the gonadossomatic index, oocyte diameter and fecundity determined. Five germ cell development stages (oogonium, perinucleolar, cortical alveoli, vitellogenic, ripe) and two other structures (postovulatory follicles and atretic oocytes) were observed in females caught in the river. Captive animals lacked the ripe oocytes and postovulatory follicles and had a relatively higher number of atretic oocytes. Females in captivity are known to produce larger oocytes, and they release fewer eggs in each spawn (absolute fecundity) when compared with animals that are able to migrate. Our results suggest that the TietA(a) River is undergoing alterations which are being reflected in the reproductive performance of S. hilarii, mainly due to the presence of atretic oocytes in females caught in the river. The lack of postovulatory follicles and ripe oocytes in captive animals reveals that migratory impediment negatively impacts final oocyte maturation. However, the stage of maturation reached is adequate for ovulation induction with hormone manipulation.
Resumo:
RNA binding proteins regulate gene expression at the posttranscriptional level and play important roles in embryonic development. Here, we report the cloning and expression of Samba, a Xenopus hnRNP that is maternally expressed and persists at least until tail bud stages. During gastrula stages, Samba is enriched in the dorsal regions. Subsequently, its expression is elevated only in neural and neural crest tissues. In the latter, Samba expression overlaps with that of Slug in migratory neural crest cells. Thereafter, Samba is maintained in the neural crest derivatives, as well as other neural tissues, including the anterior and posterior neural tube and the eyes. Overexpression of Samba in the animal pole leads to defects in neural crest migration and cranial cartilage development. Thus, Samba encodes a Xenopus hnRNP that is expressed early in neural and neural crest derivatives and may regulate crest cells migratory behavior. Developmental Dynamics 238:204-209, 2009. (C) 2008 Wiley-Liss, Inc.
Resumo:
o presente trabalho resulta de uma pesquisa de campo realizada na cidade de Porto Velho / RO, em 1990, junto a técnicos da área agrícola e da utilização de outras fontes de informações (secundárias), com o objetivo de conhecer as Políticas Públicas para o setor agrícola do Estado, identificar e analisar o seu resultado e apresentar sugestões para mudanças, considerando a população migrante. o estudo descreve e analisa as Políticas Públicas do Estado, apresenta uma visão histórica de sua formação econômica, fazendo uma reconstituição de seu passado das Fases do Extrativismo e Moderna. Analisamos a evolução de sua economia, ficando evidente que os fatos econômicos e sociais condicionaram o direcionamento de fluxos migratórios para Porto Velho, desde os seus primórdios, até hoje em proporções crescentes. Evidenciaram-se os problemas decorrentes da crescente urbanização das cidades afetadas pelo processo migratório, principalmente a população rural, as dificuldades encontradas por essa população, motivadas pela falta de políticas agrícolas adequadas. Constatou-se que as políticas agrícolas do Estado não estão sendo viáveis, face a diversos fatores, os quais são apontados no trabalho. Por fim, apontamos sugestões para uma proposta de reformulação da política para o Setor Agrícola, com vistas a superar grandes problemas na área, vividos principalmente pela população rural que migra para aquele Estado.
Resumo:
A divulgação dos primeiros blocos de resultados do Censo Demográfico de 2000 traz importantes oportunidades de constatação sobre os padrões de evolução e distribuição demográfica brasileira nos anos 90. Nesse sentido, ao tratar do comportamento reprodutivo, destaca a continuidade do declínio dos níveis de fecundidade, associando-o a mudanças na organização econômica e espacial. Quanto á mortalidade, ressalta-se sua queda sistemática nas últimas décadas. Por último, em relação ás migrações e redistribuição espacial da população, enfatizam -se as alterações nos fluxos migratórios recentes, a desaceleração do crescimento de algumas regiões metropolitanas e áreas do Sudeste , enquanto aumentam relativamente a retenção populacional no Nordeste e o deslocamento para o Norte e para o Centro-Oeste.
Resumo:
The town of Nova Friburgo, in Brazil, was founded in 1820 by swiss immigrants who, as often happens in the majority of migratory flows, crossed the ocean in search of better life conditions. The scope of this paper is to trail the path of a swiss immigrant called Marianne Joset Salusse and then follow on to investigate the mechanisms involved in elaborating family memory and public memory around this woman who would become a symbol of immigration to this town. Thus a series of interviews were held with her descendants, which were fundamental for the understanding of current representations and the main elements which constitute the collective memory around Marianne. Besides oral sources, we had recourse to written documents which allowed a retrieval of relevant information about her life. More than simply adding information, written sources allowed for a more profound analysis of oral accounts, unravelling as well as unveiling selective procedures peculiar to memory construction (Pollak, 1989;1992).
Resumo:
o presente trabalho resulta de uma pesquisa de campo realizada na cidade de Porto Velho / RO, em 1990, junto a técnicos da área agrícola e da utilização de outras fontes de informações (secundárias), com o objetivo de conhecer as Políticas Públicas para o setor agrícola do Estado, identificar e analisar o seu resultado e apresentar sugestões para mudanças, considerando a população migrante. o estudo descreve e analisa as Políticas Públicas do Estado, apresenta uma visão histórica de sua formação econômica, fazendo uma reconstituição de seu passado das Fases do Extrativismo e Moderna. Analisamos a evolução de sua economia, ficando evidente que os fatos econômicos e sociais condicionaram o direcionamento de fluxos migratórios para Porto Velho, desde os seus primórdios, até hoje em proporções crescentes. Evidenciaram-se os problemas decorrentes da crescente urbanização das cidades afetadas pelo processo migratório, principalmente a população rural, as dificuldades encontradas por essa população, motivadas pela falta de políticas agrícolas adequadas. Constatou-se que as políticas agrícolas do Estado não estão sendo viáveis, face a diversos fatores, os quais são apontados no trabalho. Por fim, apontamos sugestões para uma proposta de reformulação da política para o Setor Agrícola, com vistas a superar grandes problemas na área, vividos principalmente pela população rural que migra para aquele Estado.
Resumo:
Na década de 80 teve início o Programa de Desenvolvimento Integrado para o Noroeste do Brasil. Financiado pelo Governo Federal e o Banco Mundial sob coordenação do Governo Federal e execução de institutos federais e estaduais. Seria através do POLONOROESTE que as instituições chaves do Estado seriam criadas e/ou fortalecidas. O objetivo do POLONOROESTE era absorver o fluxo migratório de maneira coordenada e sustentável. E principalmente concluir o asfaltamento da BR-364. Na visão dos ambientalistas vários problemas surgiram a partir do POLONOROESTE. O próprio Banco Mundial chegou ã conclusão que o plano foi aplicado de forma precipitada, embora tivesse seus pontos positivos. Realizou-se em 1984 uma revisão de meio termo no programa. Apresentou, inicialmente, em versão preliminar o Zoneamento Sócio-Econômico-Ecológico que seria o instrumento básico de planejamento e ordenamento territorial. A partir de estudos feitos pelo Zoneamento Sócio-Econômico-Ecológico teve início o PLANAFLORO. O Brasil não pode estagnar seu desenvolvimento em nome da questão ambiental. O foco não é somente estratégico, mas uma questão de sobrevivência dos povos da floresta amazônica. Entendendo-se como povos da floresta todos os cidadãos que lá habitam. Inúmeros países formaram Comitês Internacionais de Defesa da Amazônia com o pensamento de que a posse da floresta amazônica pela Guiana inglesa, BrasiL Venezuela, Colômbia, Peru e Bolívia era meramente circunstancial. Que a floresta na verdade era patrimônio da humanidade. Esse nível de consciência pelo resto do mundo tem transcendido os limites da tranqüilidade dos países a que pertence a Amazônia. Problemas sociais como a denominada "chacina dos yanomamis" em Roraima, servem para que as ONG's procurem mostrar a incompetência do Brasil em administrar esse rico território.
Resumo:
The object theme of the present study is a population of caboclos that absorbed as manual workers in the saw-mills which were mounted in the highland region of Santa Catarina since 1950. The abundance of araucaria (native kind of pine) the opening of markets, and the corroboration of other industrial exploration conditions encouraged a great crowd of small en.- trepreneurs, coming basically from the state of Rio Grande do Sul, to migrate and settle down, building up a lot of saw-mills near rich forests and fields. The saw-mills started aprosperous production of timber sawn in planks. The process of industriali zation was so intensive, the destruction of pine woods soviolent that, in less than three decades, the forests ran out of tree reserves. The caboclos, absorbed as manual workers in production of timber, lived traditionally in an system of subsistense, either from the cultivation of pine the economic their land (planter caboclo) or as labourers in cattle-growing farms (farm hand caboclos). Nevertheless, the 'advantages' that were offered them by the new-comer entrepreneurs (a salary paid in money, a new house in a village, and other favours) helped the great majority of caboclos to abandon their traditional work and enlist as "workmen" in saw-mills. The new job, besides being a novelty, was an opportunity for a change in status. Subsequently, the running out of forests of araucaria and the resultant progressive shut-down of saw-mills caused the crowd of workmen to be out of imployment and to form to form a migratory flood toward the most important town of the region, Lages. The town of Lages, however, having made of the timber i ts main economic support wi thout the implantation of an alternative industry, was unable to offer the migrantssufficient 'work places'. In this way, the 'marginal crowd' began to settle down in the suburbs of the city. This study, in the context of the object theme, analyses two main questions related to the reality 'WOlLQ' and to the economic exploitation forms: ~) the relations of production in the economic regime of subsistence and in the capitalist regime of industrial production with the consequent 'positions' of the workman in the productive processj ~~) the deriving educative effects of the productive process, either in the economic regime of subsistence, or in the capitalist industrial regime. The two questions are theoretically debated andconfro~ ted with the proposed reality, giving origin to conclusions that, in a general formulation, can be summarized as follows: a) the caboclos of the highland region of Santa Catari na, when under an economic regime of subsistence, held in fee the productive processj there was a social division of the work and aclimate of freedom which made possible the development of knowledge from their life and work experience, the production of most of their tools, and the making of necessary manufactures adapted to their own surrounding ditionsi -- - --- other con- ------ b) however, these same caboclos, when absorbed by the capitalist industrial process of production - tipified by the work in saw-mills - lost the control of the productive processj this was caused by the technologic division of the work, since each man began to perform a dull and repeti tive action, directed by the speed of the 'major-saw' j man resigned form his skill and inventive power and surrendered to an executive authority which turned him into a 'collective worker'j the new productive process, besides rnaking each rnan a copy of a pattern, put the caboclos in a situation in which the daily work experiencedidn't add anything in terrns of autogenesis of knowledgei and even the environrnental educative rneans were reduced to new forrns of adaptation to the productive process, relegating rnan's inventive power to inertia.
Resumo:
The transformations economical, social and politics in you finish them decades of the century XX brought changes that didn't just limit to the production system. The flexible accumulation took many workers lost her/it their workstations and they look for her/it new survival forms, migrating for administrative activities, of services rendered and for the tourist activity of small and medium load. The State has been investing in the implantation of plans of tourist development in order to create favorable conditions for the reproduction of the tourist activity in Brazil, mainly in the Northeast. A space when it starts to present a predominant economical activity suffers a restructuring in their social and economical relationships. The restructuring of these relationships takes to the construction of a new espacialidade. In the city of Christmas, in Rio Grande do Norte, the neighborhood of Black Tip is the most representative of the public investments for the tourist development. After intense process of tourist urbanization, Black Tip passed interfering in the global context consolidating as the tourist locus in the city. The tourist urbanization of the neighborhood took to the transformation of the space in merchandise that is sold and consumed as such. The recreation of fragments of other cultures brought by social actors, resulting from migratory processes stimulated by the tourist development, it has been presenting ruled social relationships in the informational technology, consumption of global goods and in the fragmentation of the urban space characterized by the internationalization and cosmopolitização. That process has been masking the inequalities partners and cultural as well as the territorial appropriation for an economical elite. The spaces are being appropriate for investors of the tourist section, private investors, agents and real estate producers, where the inequality is not just economical, but also cultural. The local population, mainly of the urban fraction of the Town of Black Tip, it doesn't participate of the productive process in function of the little or any professional qualification and he/she doesn't also have access to the consumption process. To the native ones it remains the fight for the preservation of his/her cultural identity and for the survival
Resumo:
In recent years the heparin has been the subject of several studies that aim to expand its use as a therapeutic agent, due to its ability to modulate the activity of various proteins that play important roles in the regulation of pathophysiological processes. In several experiments and preclinical trials, heparin has demonstrated an anti-inflammatory role. However, its clinical use is limited, due to its strong anticoagulant activity and hemorrhagic complications. For this reason, considerable efforts have been employed in discovery of heparin analogous (heparinoid) with reduced side effects, that retain the anti-inflammatory properties of heparin. In this context, a heparinoid obtained from the head of Litopenaeus vannamei shrimp, which presents a structural similarity to heparin, showed, in previous studies, anti-inflammatory activity in a model of acute peritonitis with reduced anticoagulant effect in vitro and low hemorrhagic activity. Thus, the present work had as objective to evaluate the effect the heparinoid of the cephalothorax of gray shrimp on the acute inflammatory response in different times (3 or 6 hours after the induction of inflammatory stimulus), using the model of acute peritonitis induced in mice. It was also analyzed the HL effect over the activity of elastase, an enzyme involved in leukocyte recruitment. Furthermore to check if the different doses of heparin and heparinoid change the hemostatic balance in vivo, was assessed the effect of these compounds on the plasma clotting time in animals submitted to inflammation. The results show that in 3 hours, all doses of heparinoid were able to prevent efficiently in the acute inflammatory process without any anticoagulant effects, unlike the extrapolation dose of heparin, which has induced a large hemorrhage due its high anticoagulant activity. However, 6 hours after induction of inflammation, only the dosages of 0.1 and 1.0 μg/Kg of heparin and 1.0 μg/Kg of heparinoid kept anti-migratory effect, without changing of the hemostatic balance. These results indicate that the anti-migratory effect of theses compounds depends on the dosage and time of inflammatory stimulus. The HL and heparin were also able to inhibit the activity of the enzyme elastase. The discovery of this bioactive compound in the cephalothorax of shrimps can arouse great interest in biotechnology, since this compound could be useful as a structural model interesting for the development of new therapeutic agents for peritonitis
Resumo:
Piracanjuba (Brycon orbignyanus) is a Brazilian migratory fast-growing omnivore, very appreciated as a sport fish, which is threatened to extinction in Southern Brazil due to stock over exploitation and dam building. Therefore, efforts have been made to raise this fish in captivity for reintroduction and aquaculture purposes. In the present study, the effects of different dietary protein and lipid concentrations on piracanjuba fingerlings growth performance, feed utilization, body composition, hepatosomatic index (HSI) and activity of the lipogenic enzymes fatty acid synthetase (FAS), glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme (ME) were investigated using a 2 x 3 factorial experiment. Six casein-gelatin based diets were prepared combining two protein (30% and 32%) and three lipid concentrations (5.5%, 8.8% and 12.1%). Eleven fish, average weight 11.30 +/- 0.1 g, were held in each of 18 100-1 aquaria, supplied with recirculating freshwater. Each diet was randomly assigned to triplicate groups of fish and fed to apparent satiation, twice a day for 100 d. Piracanjuba fingerlings' daily weight gain (0.36-0.40 g), specific growth rate (1.43-1.51%), feed utilization and HSI were not influenced by dietary protein or lipid concentration. However, body composition was directly affected by dietary treatment. An increase in body fat and dry matter was observed as dietary lipid increased, for both dietary protein concentrations tested. The activity of FAS was depressed by increasing dietary fat levels but the G6PD activity did not differ among dietary treatments, although ME activity showed some regulation by dietary protein. These results indicate that an increase from 5.5% to 12.1% in the dietary lipid, at a dietary protein concentration of 30% or 32%, promotes body fat accumulation in piracanjuba fingerlings with no improvement in growth, suggesting that the lipid requirement for this species should be 5% or less, when raised for commercial purposes. However, the additional energy reserve from body fat accumulation could be desirable for piracanjuba fingerlings produced for stock enhancement. (C) 2003 Editions scientifiques et medicales Elsevier SAS and Ifremer/IRD/Inra/Cemagref. All rights reserved.
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)