Navegando por Data de Publicação, começando com "2004-06-25"

Filtrar resultados por ano ou mês

Agora exibindo 1 - 3 de 3

Contribuição ao desenvolvimento de metodologia para detecção de desintegrina recombinante produzida em cultivos de células CHO-K1
(Universidade Federal de São Carlos, 2004-06-25) Silva, Gracinda Marina Castelo da; Zangirolami, Teresa Cristina; https://lattes.cnpq.br/4546701843297248
Disintegrins are proteins present in the poison of serpents that have been calling the pharmaceutical industry attention due to their capacity to prevent the progression of cancerous cells. A receiving key-protein called integrin addresses the formation of new blood vessels instructing the tumor cells to increase and spread. The disintegrin acts as an inhibitor that blocks this interaction. In order to produce substantial amounts of disintegrin in industrial scale, its expression in CHO-K1 cells was carried out by cloning the characteristic DNA extracted from the poison producing glands of the serpent Agkistrodon contortrix laticinctus. Usually CHO-K1 cells are cultivated in medium containing bovine fetal serum. However, its presence in the cultivation medium hinders the stages of detection, extraction and purification of the protein of interest. The objective of this work was to study the CHOZMD cell growth and the desintegrin production in serum free medium, as well as to develope a methodology for the detection and quantification of the disintegrin present in the medium. The cultivations were carried in culture bottles of 25cm2, 75cm2 and 150cm2 and later in spinner flask with a volume of 500mL, incubated with an amount of CO2 controlled in 10% v/v, pH between 7.0 to 7.4, a temperature of 37 °C, under agitation conditions. The cells were cultivated in the presence of the microcarrrier Pronectin F which enables the attainment of high cell concentration. The culture media DMEM and CHO-S-SFM II were used in the cultivations by means of a gradual adaptation process for a serum free medium, through the reduction of DMEM+serum proportion at each change, until that it was totally replaced by the serum free medium. The cells were maintained in 100% serum free medium during 6h with the withdrawal of 250 ml after 3 h and of the remaining volume after 6h of cultivation. For the detection of the disintegrin, the samples were initially filtered in Milipore filter, then concentrated in ultra filter Amicon and finally centrifuged in membranes Centriprep and Centricon. The disintegrin, protein of ~70kDa, present in the treated samples was detected using Bio Dot equipment with nitrocelulose membrane incubated with specific antibodies. The samples were applied in ion exchange column and the fractions obtained applied in nitrocelulose membrane. In the cultivations carried out in serum free medium with the microcarrier Pronectin F a maximum cell concentration of 1.74.106 cel.ml-1 was reached, which is slightly inferior to the value reached in the cultivations in medium containing serum (2.7.106 cel.mL-1). However, concerning product formation, the immunodetecion results revealed the presence of the disintegrin in the cultivations carried out with serum free medium. Cultivations carried out in spinner flask, with a volume of 200mL and using microcarrier Citodex 1 and medium supplemented with 1% hemolymph (v/v) presented maximum cell concentration of 2.6.106 cel.mL-1. The detection method developed was effective in the identification of the target protein in the samples from the cultivation medium containing hemolymph. Preliminary tests demonstrated loss of protein might be related to gradual degradation in cultivation medium or retention in ion exchange column.
Incorporação da gestão dos custos do ciclo de vida ao processo de desenvolvimento do produto da EMBRAER.
(Universidade Federal de São Carlos, 2004-06-25) Freixo, Osvaldo Magno; Toledo, José Carlos de; https://lattes.cnpq.br/9421627326330417
The Product Development Process (PDP) is one of the fundamental business processes of an organization and therefore should be conducted harmonically with the other company processes, as well as with the established strategies for competitiveness and profitability. One of these strategies is to offer the market products at reduced costs, which is a result of development, manufacturing, operation, maintenance and even discarding products once they have reached the end of their life cycle. These costs, called Life Cycle Costs (LCC), are closely related to Product Development, since the decisions taken during its process define costs in each phase of the product s life cycle. A Product Development Model should include a definition of the activities, information and responsibilities regarding the impact that each engineering decision has on the product s Life Cycle Costs. This definition leads to a LCC Management Model, considered, then, a sub-model of PDP. The objectives of this research were as follows: (a) to incorporate LCC management activities into the PDP of a company, with the participation of people that work with Product Development; (b) based on the literature and the case study developed, to prepare guidelines with recommendations for companies interested in implementing a similar project. The Action-research method was used in the study, and the LCC Management Model was developed at EMBRAER Empresa Brasileira de Aeronáutica S/A (a Brazilian aeronautics company). The main conclusions of our research indicate that the involvement of the people that participate in the PDP is crucial when preparing the LCC management models. However, these people should be adequately prepared to take part in a project of this nature, enabling real management and the implementation of a company culture concerning LCC. The results have also shown that the Action-research method is effective in identifying the opportunities of improvement of the Product Development Process and in proposing Life Cycle Costs management practices.
Síntese e caracterização a nível nanométrico da fase Li2(M) Ti308, M=Zn, Co e Ni pelo método Pechini.
(Universidade Federal de São Carlos, 2004-06-25) Câmara, Maria Suely Costa da; Longo, Elson; https://lattes.cnpq.br/9848311210578810
The present work describes the preparation and characterization of the spinel phases Li2ZnTi3O8, Li2CoTi3O8 and Li2NiTi3O8 synthesized by the polymeric precursor method. Polycrystalline ceramic powders of high quality were synthesized for the Li2ZnTi3O8 and Li2CoTi3O8 phases. The desired spinel phase of the Li2NiTi3O8 compound was not obtained, however the synthesis product consisted of other crystalline phases. The chromatic and luminescent properties of the powders were investigated. The powers were calcined in temperatures between 400oC-1000oC/4h, after the obtention of the puff , in a heat treatment at 400oC/1h. The evolution of the crystalline phases with calcination temperature was investigated by means of X-ray Diffraction and Raman Spectroscopy, where it was verified that the Li2ZnTi3O8 and Li2CoTi3O8 crystalline phases could be obtained at low temperature (500oC). The Rietveld refinement method was used to observe in greater detail the crystalline structures of the spinels, and to study the occupations of the octahedric and tetrahedric lattice sites. The particle characteristics were studied by crystallite size and specific superficial area measurements, scanning electron microscopy and transmission electron microscopy. The results show that the synthesized powders present dimensions in the nanometer scale. The pigment of the Li2CoTi3O8 phase presented a green color for calcination temperatures of 400oC (amorphous) and 500oC (phase with structural defects). In temperatures above 600oC, the pigment presented a green-blue color with stability up to 1250oC. The observed pigment color transition from green to blue is due to the cobalt occupation in tetrahedric and octahedric sites. The Li2NiTi3O8 phase resulted in yellow pigments of excellent stability. The non-crystalline Li2ZnTi3O8 phase presented photoluminescent properties. The crystallization of this material provoked the quenching of the photoluminescent emission. A quantummechanical computer simulation confirms that the non-crystallinity of this material induces the formation of electronic levels, reducing the effective band gap energy when compared to the crystalline phase. This might explain the behavior of the photoluminescence in this spinel phase.