The stability and aggregation properties of the GTPase domain from human SEPT4

The septins are a family of conserved proteins involved in cytokinesis and cortical organization. An increasing amount of data implicates different septins in diverse pathological conditions including neurodegenerative disorders, neoplasia and infections. Human SEPT4 is a member of this family and its tissue-specific ectopic expression profile in colorectal and urologic cancer makes it a useful diagnostic biomarker. Thermal unfolding of the GTPase domain of SEPT4 (SEPT4-G) revealed an unfolding intermediate which rapidly aggregates into amyloid-like fibers under physiological conditions. In this study, we examined the effects of protein concentration, pH and metals ions on the aggregation process of recombinant SEPT4-G using a series of biophysical techniques, which were also employed to study chemical unfolding and stability. Divalent metal ions caused significant acceleration to the rate of SEPT4-G aggregation. Urea induced unfolding was shown to proceed via the formation of a partially unfolded intermediate state which unfolds further at higher urea concentrations. The intermediate is a compact dimer which is unable to bind GTR At 1 M urea concentration, the intermediate state was plagued by irreversible aggregation at temperatures above 30 degrees C. However, higher urea concentration resulted in a marked decay of the aggregation, indicating that the partially folded structures may be necessary for the formation of these aggregates. The results presented here are consistent with the recently determined crystal structure of human septins and shed light on the aggregation properties of SEPT4 pertinent to its involvement in neurodegenerative disease. (C) 2008 Elsevier B.V. All rights reserved.

Mg(2+) Ions Bind at the C-Terminal Region of Skeletal Muscle alpha-Tropomyosin

Tropomyosin (Tm) is a dimeric coiled-coil protein that polymerizes through head-to-tail interactions. These polymers bind along actin filaments and play an important role in the regulation of muscle contraction. Analysis of its primary structure shows that Tm is rich in acidic residues, which are clustered along the molecule and may from sites for divalent cation binding. In a previous study, we showed that the Mg(2+)-induced increase in stability of the C-terminal half of Tin is sensitive to imitations near the C-terminus. In the present report, we study the interaction between Mg(2+) and full-length Tin and smaller fragments corresponding to the last 65 and 26 Tin residues. Although the smaller Tin peptide (Tm(259-284(W269))) is flexible and to large extent unstructured, the larger Tm(220-284(W269)) fragments forms a coiled coil in solution whose stability increases significantly in the presence of Mg(2+). NMR analysis shows thin Mg(2+) induces chemical shift perturbations in both Tm(220-284(W269)) and Tm(259-284(W269)) in the vicinity of His276, in which are located several negatively charged residues. (C) 2009 Wiley Periodicals, Inc. Biopolymers 91: 583-590, 2009.

Spectroscopic study of the polymerization of intercalated anilinium ions in different montmorillonite clays

The polymerization of the intercalated aniline ions was studied in three different clays, Swy2-montmorillonite (MMT), synthetic mica-montmorillonite (Synl) and pillarized Swy2-montmorillonite (PILC). PANI is formed between the MMT and Syn1 clay layers, being confirmed by the shift of d(001) peak in the X-ray pattern. X-ray Absorption near to Si K edge (Si K XANES) data show that the structures of clays are preserved after the polymerization process and in addition to the SEM images show that morphologies of the clays are maintained after polymerization, indicating no polymerization in their external surface. UV-vis-NIR and resonance Raman data display that the PANI formed in Syn1 galleries has higher amount of phenazinic rings than observed for PANI intercalated in montmorillonite (MMT) clay. No polymer formation was detected in the PILC. N K XANES and EPR spectroscopies show the presence of azo and radical nitrogen in intercalated PAN! chains. Hence, the results are rationalized considering the structural differences between the clays for understanding the role of the anilinium polymerization within the clays galleries. (C) 2011 Elsevier B.V. All rights reserved.

Sistemas de controle de vendas no setor têxtil: um estudo exploratório

Esta dissertação estuda os sistemas de controle de vendas praticados pela indústria têxtil brasileira diante das mudanças ambientais ocorridas nas últimas duas décadas. O pressuposto básico para a utilização de sistemas de controle para a equipe de vendas é que através deles é possível dirigir e influenciar as atitudes e os comportamentos dos empregados para conseguir atingir seus objetivos, havendo uma estreita relação entre a forma como a gerência comercial monitora, dirige, avalia e recompensa as atividades dos seus vendedores e a efetividade da área comercial, sendo diferenciais decisivos para atender a pressão por competitividade e as exigências do mercado quanto ao posicionamento da equipe comercial frente ao novo cenário de negócios. Da revisão teórica foram levantados os oito principais modelos de sistemas de controle e aspectos importantes que devem ser considerados para a composição do sistema de cada empresa. A pesquisa foi conduzida entre os responsáveis por equipes de vendas no segmento têxtil nos elos onde vendas industriais são realizadas. Empregaram-se técnicas empíricas para o levantamento das freqüências de incidência dos aspectos estudados e foi possível constatar que os elos de fibras e filamentos, fiação, tecelagem, malharia e beneficiamento do segmento têxtil possuem sistemas de controle pertinentes com as características de venda industrial. Os controles formais estão ligados a resultados e os controles informais estão relacionados com o acompanhamento das atividades e capacidades do vendedor. Adicionalmente buscou-se captar a percepção dos responsáveis por equipes comerciais sobre sua efetividade nos aspectos de volume de vendas, lucratividade, participação de mercado e também satisfação do cliente.

Ecologia do fitoplâncton impactado por cultivo de tilápia do Nilo, oreochromis niloticus, em tanques-rede no açude Ministro João Alves, Parelhas, Rio Grande do Norte

The dams are limnic ecosystems of great importance for its multiple uses, among them, water supply for the public and to culture of artisanal fish are most relevant. The aim of the present study is to evaluate the physical-chemical characteristics and the phytoplankton community in two chosen sites (Point 1 littoral zone of point source; Point 2 pelagic zone of non-point source) of the Minister João Alves dam, which is also known as Boqueirão de Parelhas/RN. This represents the spatial distribution of the phytoplankton species in order to understand any possible alterations of the water quality and the phytoplankton composition in relation to the water quality originating from the impact of the tilapia, Oreochromis niloticus, culture. The study period also encompasses temporal variations exhibited in two seasons of an annual cycle, one during the dry season (Oct, Nov and Dec of 2008 and Jan of 2009), and the other rainy season (Mar, Apr, May and June of 2008) to extend the observation. The physicalchemical parameters, such as pH, temperature, electrical conductivity, concentration of dissolved oxygen were measured in situ and the values of the inorganic nutrients (nitrate, ammonium and orto-phosfato) and chlorophyll in the laboratory. The quali-quantitative analyses of the phytoplankton had been carried through sedimentation technique and the enumeration of the random of 400 cells, colonies and filaments counted using Sedgwick-Rafter counting chamber. The results of pH varied widely from the acidic to alkaline range with the minimum of 5.8 (± 0.8) and the maximum of 9.2 (± 0.7-0.8), at point 1 and 2. The dissolved oxygen content was higher in the rainy period than that in the dry period. The maximum electrical conductivity was of 1409 μScm-1 in point 1 and 431 minim of μScm-1, in point 2. There was a considerable alteration in the levels of inorganic nutrients such as nitrate-nitrogen, ammoniacal nitrogen and orthophosphate during the two cycles of study period. Phytoplankton assemblages presented a picture of alternate dominance among species Cyanobacteria, Bacillariophyceae and Chlorophyceae. The trophic state index diagnosed to the category of mesotrophic, which is based on the values of chlorophyll, total phosphorus and Secchi-disc measurements. The wind driven turbulence of the water column and the fresh inflow of water (flushing and dilution) during rainy season acted as constraint and did-not allow an exaggerated growth of the species of cyanobacteria. On the basis of the present we conclude that the culture of tilapias in cage-culture fails to produce pollution load that could compromise the quality of the water of the dam, probably be due to small dimension of the culture in relation to the size, volume of the water and the reservoir capacity support its own environment

Estudo comparativo da variação temporal da comunidade fitoplanctônica do açude Cruzeta inserido no bioma caatinga, Rio Grande do Norte

The Cruzeta impoundment, situated in the city of Cruzeta, hinterland of the state of the Rio Grande do Norte state has significant importance to the municipality as it represents the only source of supplying water to the region. It was hypothesized that the regional consequence of the global warming and the warming of surface water could substantially contribute the significant growth of the aquatic macrophytes in the years 2008-2009. The growth of these vegetation believed to be improved the degree of water transparency and as a consequence of the improved growth of phytoplankton species and chlorophyll biomass. At the same time the aquatic macrophyte could interact and compete potentially for the dissolved inorganic nutrients resources and the phytoplankton community. This study presents a comparison of years 2004-2005 when it did not have the expressive presence of the aquatic macrophyte community or restricted to the littoral region. In contrast, the years 2008-2009 showed a significant growth of the aquatic macrophyte in the Cruzeta/RN impoundments. The present study is an attempt to elucidate the significant presence of the aquatic macrophyte, Eichhornia crassipes, Ceratophyllum submersum, Nymphea sp and Pistia sp, and its interference on the ecology of phytoplankton. The samplings had been carried out from September of 2008 to April of 2009 and consistently between 10:00 h and 12:00 h with the aid of Van Dorn bottle and the plankton net of mesh size 20 Qm. The collections were made in three depths ie., surface, mid-column and bottom. The Physical-Chemical parameters such as pH, temperature, electrical conductivity and dissolved oxygen had been analyzed in situ. The samples for analysis of nutrients and chlorophyll were kept under refrigeration for posterior analysis in the laboratory. Phytoplankton samples were preserved in Lugol-iodine and kept for sedimentation for quali-quantitative analysis of phytoplankton. Enumeration of cells, colonies and filaments was done with the aid of Sedgwick-Rafter counting chamber and expressed as numbers/ml. Chlorophyll a was analyzed as a functional component of phytoplankton biomass and extracted with cold 90% acetone. The results indicate that the chlorophyll concentration varied between 5,65-8,08 Qg.L-1 for the dry period and 5,09-6,23 Qg.L-1 for the rainy period and showed considerable reduction when compared to the values to the 2004-2005 study period. The temperature was always presented higher in relation to the 2004-2005 study. Phytoplankton species showed a relative abundance of the Cyanophyceae for both the period of dry and rainy. The predominance species are filamentous Leptolymbya geophila Borzi (Planctolyngbya sp), Anabaena plankctônica Brunnthaler, Oscillatória limosa Ag. and Cylindrospermopsis raciborskii (Wolosz). The concentration of the nutrients such as nitrate and orto-phosfato had always presented higher values during the rainy period and the ammoniacal nitrogen retained moderate values in the dry period and a slight increase in rainy season. The main conclusions are the reduction of the concentration of chlorophyll, diversity of phytoplankton, and the increase in temperature and transparency of the water during the period of the study

Pre-emptive epidural ketamine or S(+)-ketamine in post-incisional pain in dogs: A comparative study

Objective-To compare the pre-emptive analgesic effects of epidural ketamine or S(+)-ketamine on post-incisional hyperalgesia.Study Design-Prospective randomized study.Animals-Twenty-four mongrel dogs (1-5 years, weighing 11.9 +/- 1.8 kg).Methods-Dogs were anesthetized with propofol (5 mg/kg intravenously) and a lumbosacral epidural catheter was placed. Dogs were randomly allocated to 3 groups, each with 8 dogs. The control group (CG) was administered saline solution (0.3 mL/kg); the ketamine group (KG) ketamine (0.6 mg/kg); and the S(+)-ketamine group (SG) S(+)-ketamine (0.6 mg/kg). The final volume was adjusted to 0.3 mL/kg in all groups. Five minutes after the epidural injection a surgical incision was made in the common pad of the right hind limb and was immediately closed with simple interrupted nylon suture. Respiratory (RR) and heart (HR) rates, rectal temperature (7, sedation (S), lameness score, and mechanical nociceptive threshold by von Frey filaments were evaluated before the propofol anesthesia and at 15, 30, 45, 60, 75, and 90 minutes and then at 2, 4, 6, 8, 12, and 24 hours after epidural injection.Results-There were no differences in RR, HR, T, or S between groups. Motor blockade of the hind limbs was observed during 20 +/- 3.6 minutes in KG and during 30.6 +/- 7.5 minutes in SG (mean SD). Mechanical force applied to obtain an aversive response was higher from 45 minutes to 12 hours in KG and from 60 to 90 minutes in SG, when compared with CG.Conclusions-Pre-emptive epidural ketamine induced no alterations in RR and FIR, and reduced post-incisional hyperalgesia for a longer time than did S(+) ketamine.Clinical Relevance-Although anesthetic and analgesic potency of S(+) ketamine is twice that of ketamine, the racemic form is seemingly better for post-incisional hyperalgesia. (C) Copyright 2004 by the American College of Veterinary Surgeons.

Efeitos comportamental, clínico e analgésico promovidos pela injeção epidural preventiva de morfina, xilazina ou clonidina, em equinos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Astrócitos imunorreativos à proteína glial fibrilar ácida (GFAP) em sistema nervoso central de equinos normais e de equinos com leucoencefalomalácia

A proteína glial fibrilar ácida (GFAP), subunidade dos filamentos intermediários do citoesqueleto celular, está presente no citoplasma de astrócitos. Técnicas imunohistoquímicas com anticorpos primários anti-GFAP são geralmente empregadas para identificar astrócitos no sistema nervoso, permitindo verificar também sua hipertrofia. Vários estudos mostram a distribuição, a morfologia e a citoarquitetura de astrócitos em várias regiões do SNC do homem e de animais de laboratório. No entanto, em animais domésticos e, especialmente em equinos, poucas informações estão disponíveis. No presente trabalho, verificou-se a densidade e a morfologia de astrócitos imunorreativos à GFAP na substância branca da córtex cerebral de equinos com leucoencefalomalácia (LEM) comparando-se esses aspectos com o de equinos normais. Animais com LEM apresentaram hipertrofia de astrócitos em áreas próximas às lesões, representada pelo aumento do corpo celular, do núcleo e dos prolongamentos citoplasmáticos. O número de astrócitos apresentou-se reduzido e a imunorreatividade foi mais acentuada. Nos animais normais, verificou-se distribuição constante de astrócitos imunorreagentes com características de fibrosos. Alterações vasculares nos animais com LEM, como por exemplo degeneração de endotélio vascular, também foram observadas, podendo estar associadas às alterações astrocíticas.

Caracterização morfológica e química de frutos de rambutan

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Aplicação de danos mecânicos em abacates e seus efeitos na qualidade dos frutos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fabricação de malha de trama utilizada como pré-formas na indústria de compósitos e avaliação das propriedades mecânicas

In the manufacture of composite, textile materials are being used as reinforcement. Generally, the combination of the matrix with the textile material in the form of fibres or yarns is used depending on their distribution in the web. In the present work, in place of fibres or yarns, a knitted structure in the form of the final product which is defined as preform. The preform is weft knit manufactured with polyester filaments. In the manufacture of composite, polyester resin was used as matrix. The physical and mechanical properties as well as the formability of the weft knit were analysed. The physical and mechanical properties as well as the formability of the knitted structure were analysed. The results obtained on the analysis show that the courses and wales of the weft knit structure and the tensile properties help the formability of the structure and the impregnation of the resin. It could be clearly observed that composite structure in the direction of the courses support more tension than in the direction of the wales. In relation to the three points flexural tests it was possible to note that there was more flexion in the direction of wales, what was expected. It was also possible to note that there are other advantages such as reduction in the loss of materials used, homogeneity in the distribution of the knitted structure in the mould, reduction in the preparation time and also in the reduction in the cost of manufacture

Resistência genética em genótipos de feijoeiro a Curtobacterium flaccumfaciens pv. flaccumfaciens

Curtobacterium flaccumfaciens pv. flaccumfaciens (Cff) agente causal da murcha-de-curtobacterium em feijoeiro (Phaseolus vulgaris), é um patógeno vascular de difícil controle. A doença foi detectada pela primeira vez no Brasil na safra das águas de 1995, no Estado de São Paulo. Por se tratar de uma doença de difícil controle, a resistência genética tem sido a melhor opção. O objetivo deste trabalho foi avaliar a reação de genótipos de feijoeiro à murcha-de-curtobacterium, frente a 333 acessos pertencentes ao banco de germoplasma de feijoeiro do Instituto Agronômico de Campinas (IAC). Oportunamente, foram selecionados genótipos de feijoeiro altamente resistentes e suscetíveis, com a finalidade de comparar a colonização de Cff no vaso do xilema a partir da visualização sob microscopia eletrônica de varredura. Os resultados da triagem da resistência genética em genótipos de feijoeiro indicaram a existência de variabilidade genética nas amostras dos 333 genótipos avaliados, ao isolado de Cff Feij 2634. Os materiais foram classificados em 4 grupos de resistência: 29 genótipos (8,7%) comportaram-se como altamente resistentes, 13 genótipos (3,9%) como resistentes, 18 genótipos (5%) como moderadamente resistentes e 273 genótipos (81%) suscetíveis. A partir dos resultados obtidos, cerca de 18% dos genótipos de feijoeiros, desde altamente resistentes à moderadamente resistentes, poderão ser úteis para o programa de melhoramento genético como fonte de genes para resistência a Cff. Através da microscopia eletrônica de varredura, foram observadas em genótipos altamente resistentes, várias aglutinações da bactéria envolvidas por filamentos e estruturas rendilhadas sob pontuações da parede do vaso do xilema, não verificados em genótipos suscetíveis, o que sugere a ativação de mecanismos de defesa estruturais e bioquímicos nas plantas resistentes.

Distribuição de macroalgas lóticas de uma bacia de drenagem no Parque Nacional da Serra da Canastra, Minas Gerais, Brasil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ecological distribution of stream macroalgae in different spatial scales using taxonomic and morphological groups

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)