Viabilidade técnica de uma rota não convencional para a produção de leite de cabra em pó em cooperativas do Rio Grande do Norte

Nowadays, Brazil has both the greatest goat herd and the greatest goat milk production of South America. The state of Rio Grande do Norte, located in northeast of Brazil, has an average year production of three thousand cubic meters of goat milk in natura. Part of this milk production is homemade and it comes from small farms, which unite in rural cooperatives created to encourage the production and implementation of industrial processes for preservation and processing of milk. Results presented by literature and obtained from preliminary essays in this thesis show that non conventional dryer of spouted bed with inert particles is able to produce powder milk from in natura milk (cattle or goat), with the same quality of spray dryer, however, operating at low cost. The method of drying in spouted bed consists of injecting milk emulsion on the bed of inert particles gushed by hot air. This emulsion covers the particles with a thin film, which dries and is reduced to powder during the circulation of inerts inside the bed. The powder is dragged by exhaustion air and separated in the cyclone. The friction among particles resulted from the particles circulation, encourages high taxes of shear in the thin film of emulsion, breaking the cohesive forces and making this process possible. Studying the drying process and the powder goat milk production in one unit of spouted bed with inert particles, seeing the development of a low cost technological route for powder milk production is the aim of this thesis. The powder milk produced by this route must attend the local demand of food industries which need an intermediate product to be used as a food ingredient (ice-cream, milk candy). In order to reach this aim, this thesis approaches the aspects related to physical, thermodynamics and physic-chemicals characteristics of goat milk, whose complete data are still inexistent in the literature. The properties of materials are of great importance to the project of any process which involves the operations of transportation of movement, heat and mass quantity, such as the dryers which operate in fluid dynamically active regime, like the spouted bed. It was obtained new data related to the goat milk properties in function of concentration of solids and temperature. It is also important to mention the study developed about the kinetic of solids retention in the bed of inert particles during the drying of goat milk. It was found more adequate processes conditions to the proposed technological route to be implemented in small and micro-industries, with simplifications in the system of milk injection as well as in the form of operation of the dryer. Important data were obtained for a posterior stage of this research which involves the v modeling, simulation, control and optimization of the process. The results obtained in this thesis, in relation to process performance as well as to the quality of produced powder milk validate the proposal of using the spouted bed dryer in the production of powder goat milk

Caracterização genética de vacas leiteiras por meio de marcadores moleculares e suas implicações na composição e qualidade do leite

The objective of this study was to identify DNA polymorphisms at the genes leptin, β-lactoglobulin and pituitary-specific transcription factor in three genetic groups of Holstein x Guzerat dairy cows and investigate the relationship between their genotypes and the composition and quality of milk of dairy cows. Samples were collected in August 2009, being 113 blood samples from lactating crossbred cows and 58 milk samples. For analysis of DNA polymorphisms blood samples were collected, analyzed later in the Genetic Laboratory affiliated to the Zootechny Institute of São Paulo and individual milk samples were collected according to standards established by the laboratory of Management Program of Northeast Dairy Herds (PROGEN), at Federal Rural University of Pernambuco (UFRPE) for analysis of milk composition and quality. The characterization of genotypes was performed by PCR-RFLP, for which were designed specific primers for each studied gene and restriction enzymes Kpn2I, HaeIII and HinfI that cut the DNA of the following genes: leptin, β-lactoglobulin and a PIT, respectively. The leptin estimate genotypic frequence were CC 0.112, TT 0.225 and CT 0.661, for β-lactoglobulin were AA 0.136, AB 0.323 and BB 0.539, and for PIT were ++ 0.655, -- 0.311 and +- 0.032. The results show that the population is in Hardy-Weinberg disequilibrium for leptin, β-lactoglobulin and a PIT due to excess of heterozygotes in the population, however, as these genes are associated with the milk production it is considered that the animals have genetic potential for milk production in the Brazilian semi-arid conditions. Through the characterization of the studied herd there were not found implications of the polymorphism of leptin, β-lactoglobulin and PIT in the composition and quality of milk from cows in the different genetic groups 1/2, 3/4 and 7/8 Holstein x Guzerat. Key words: β-lactoglobulin, crossbred cows, leptin, PCR-RFLP, PIT1, semi-arid.

Efeito do tratamento com as drogas antipsicóticas haloperidol e clozapina sobre a infecção de toxoplasma gondii em cultura de células retinianas embrionárias

T. gondii is an obligate intracellular protozoan and the main cause of retinochoroiditis in humans. The aim of this study was to evaluate the effect of the antipsychotic drugs haloperidol and clozapine on the course of infection by T. gondii of cultured embryonic retinal cells. Embryo retinas of Gallus gallus domesticus (E12) were used for the preparation of mixed monolayer cultures of retinal cells. Cultures were maintained on plates of 96 and 24 wells by 37°C in DMEM medium supplemented with 5% fetal bovine serum for 2 days. After this period, cultures were simultaneously infected with tachyzoites of T. gondii and treated with the antipsychotics haloperidol and clozapine for 48 hours. Treatment effects were determined by both assessing cell viability with the MTT method and evaluating infection outcomes in slides stained with Giemsa. The treatment with haloperidol and clozapine cells infected with T. gondii resulted in higher viability of these cells, suggesting a possible prevention of neuronal degeneration induced by T. gondii. Additionally, intracellular replication of this protozoan in cells treated with haloperidol and clozapine were significantly reduced, possibly by modulation of the parasite s intracellular calcium concentration

Influência da laserterapia na proliferação de células-tronco do ligamento periodontal humano

Low level laser irradiation (LLLI) has been used in Dentistry to promote wound healing and tissue regeneration. The literature shows a positive effect of LLLI on cell proliferation, but little is known about their effectiveness in promoting stem cells proliferation. The aim of this study was to evaluate the effect of LLLI on the proliferative rate of human periodontal ligament stem cells. Extracts of periodontal ligament were isolated from two third molars removed by surgical and/or orthodontic indication. After enzymatic digestion, the cells were grown in α-MEM culture medium supplemented with antibiotics and 15% fetal bovine serum. On the third subculture, the cells were irradiated with a InGaAlP-diode laser, using two different energy densities (0,5J/cm 2 - 16 seconds and 1,0J/cm² - 33 seconds), with wavelength of 660nm and output power of 30mW. A new irradiation, using the same parameters, was performed 48h after the first. A control group (non irradiated) was kept under the same experimental culture conditions. The Trypan blue exclusion test and the mitochondrial activity of the cells measured by MTT [3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide] essay were performed to assess the cell proliferation in the intervals of 0, 24, 48 e 72 h after irradiation. The data of cell counts were submitted to nonparametrical statistical tests (Kruskal-Wallis and Mann-Whitney), considering a confidence interval of 95%. DAPI (4 -6-Diamidino-2-phenylindole) staining of the cells was performed at 72h interval to evaluate possible nuclear morphological changes induced by LLLI. The results of this study show that the energy density of 1,0 J/cm² promoted greater cell proliferation compared to the other groups (control and 0,5 J/cm²) at intervals of 48 and 72h. The mitochondrial activity measured by MTT essay showed similar results to the Trypan blue cell counting test. The group irradiated with 1,0J/cm² exhibited a significantly higher MTT activity in the intervals of 48 and 72h, when compared to the group irradiated with 0,5J/cm². No nuclear morphological change was observed in the cells from the three groups studied. It is concluded that LLLI has stimulatory effects on the proliferation of human periodontal ligament stem cells. Therefore, the use of laser irradiation in this cell type may be important to promote future advances in periodontal regeneration

Atividade biológica de células-tronco da polpa de dentes decíduos humanos submetidas à criopreservação

Dental pulp stem cells have been widely investigated because of their ability to differentiate into both dental and non-dental cells, with potential use in therapies involving tissue engineering. The technique of cell cryopreservation represents a viable alternative for the conservation of these cells, since it stops reversibly, in a controlled manner, all of cell biological functions in an ultra low temperature. The present study aimed to evaluate, using in vitro experiments, the influence of a cryopreservation protocol on the biologic acti vity of stem cells from human exfoliated deciduous teeth (SHED). Cells obtained from the pulp of three deciduous teeth on end-stage exfoliation or with indicated extraction were expanded in α-MEM culture medium supplemented with antibiotics and 15% fetal bovine serum. At second subculture (P2), a group of cells were submitted to cryopreservation for 30 days in 10% DMSO diluted in fetal bovine serum, at -80º C, while the remind cells continued under normal conditions of cell culture. Cell proliferation was evaluated in both groups (not cryopreserved or cryopreserved) by Trypan blue stain essay at intervals of 24, 48 and 72h after plating. Cell cycle analysis of SHEDs submitted or not to the cryopreservation protocol was performed in the same intervals. Events related to cell death were studied by Annexyn V and PI expression under flow cytometry at the intervals of 24 and 72h. The presence of nuclear morphological changes was evaluated by DAPI staining at 72h interval. It was observed that both groups exhibited an upward cell proliferation curve, without considerable changes in cell viability throughout the experiment. The distribution of cell in the cell cycle phasis was consistent with cell proliferation in both groups. There were no nuclear morphological damages in the end range of the experiment. therefore, it is concluded that the proposed cryopreservation protocol is efficient for storing the studied cell type, allowing its use in future experimental studies