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Efeitos da pinealectomia sobre o tecido ósseo de ratos intactos e orquiectomizados
(Universidade Federal de São Carlos, 2005-12-09) Bertoncello, Dernival; Nonaka, Keico Okino; https://lattes.cnpq.br/4551036775738296
Osteoporosis is an important world s public health problem. The resulting fracture from this sickness becomes concerning, because it can start other problems. So, the mortality and morbidity that follow the osteoporosis diagnosis are concerning, once a high rate in old people can be seen. Based on evidences found in literature regarding the melatonin effects on bone tissue, the aim of this study was to check the possible consequences of the absence of melatonin, (pinealectomy) on body weight and femur of rats, from distinct bone analysis. It was used male rats of the Wistar strain (220-260g BW), bred at the Universidade Federal de São Carlos, were housed under conditions controlled for temperature (22±1oC) and light (lights on between 8 am and 6 pm daily). All rats were allowed free access to water and a pelleted standard commercial diet. The experimental protocol was divided in 8 groups (each group n=7): Basal; Pinealectomized-Sham; Pinealectomized and Intact (non-orchidectomized); Pinealectomized and Orchidectomized; Pinealectomized, Orchidectomized treated with Melatonin; Pinealectomized, Orchidectomized treated with Saline; Pinealectomized and Intact treated with Melatonin; Pinealectomized and Intact treated with Saline. Some groups of animals received hormonal replacement with subcutaneous melatonin injections at a dose of 200ug/kg, during 8 weeks (six days a week). Then, biometric, physical and biomechanical right femur analysis were done. It was also analyzed the body weight of each animal and bone quality. Bone mineral density was analysed on the left femur, as well as scanning electron microscopy of bone histomorphology. Pinealectomized animals treated with melatonin evoked a lower body weight increase in relation to their respective control groups. Pinealectomy associated with castration seems to enhance osteopeny indicators values, what isn´t corrected by hormonal replacement. Results from differents parameters were smallest to pinealectomized and orchidectomized rats, or only orchidectomized rats, in relation to Basal and Sham groups. Hormonal replacement is to pinealectomized and non-castrated animals enough to allow higher Maximum Force values in the flex test of the femur and protect from loss of bone density and avoid the formation of big spaces in cancellous bone. This study has shown for the first time that Pinealectomy seems to enhance the osteopeny effects of orchidectomy in rats.
Refrigeração evaporativa de telhados por meio de gotejamento de água. Experimento em bancada de testes
(Universidade Federal de São Carlos, 2005-12-09) Nascimento, Gustavo Rosas; Roriz, Maurício; https://lattes.cnpq.br/6355579765506588
The cooling effect of evaporation is used in dry climates buildings since ancient times. Water evaporation can remove heat of roofs, cooling the interior of buildings indirectly. This study presents the measurement results of a test bed which received two identical tiles, one of them receiving water application and the other kept dry. Its objective was to investigate the effects that the evaporation provokes on internal surface temperature of ceramic tiles and fibrocement tiles. Using regression analyses, strong correlations were found among the falls observed in tiles internal surface temperatures and the climatic conditions. The evaporation provoked reduction of until 18,7 oC in the ceramic roof and until 17ºC reduction in the fibrocement one.
Nitrosilo complexos de rutênio com ligantes bifosfínicos: espectroscopia, eletroquímica, estudo da reatividade e liberação de NO
(Universidade Federal de São Carlos, 2005-12-09) Poelhsitz, Gustavo Von; Batista, Alzir Azevedo; https://lattes.cnpq.br/6469642481998660
In this thesis some series of ruthenium nitrosyl complexes presenting as common characteristic the presence of diphosphines ligands in their structures, among them: dppm, dppe, c-dppen, dppp, dppb, dcpe and dppf were studied. It was sought in each series to evaluate the electronic properties of the coordinated NO as a function of the changes in the diphosphine ligand as well as to compare the NO properties among the series, in this case the characteristics of the other co-ligands were considered. The usual techniques were used to characterize the complexes: IR, UV/vis, NMR and for some compounds 15N{1H}NMR spectroscopies, mass spectrometry, cyclic voltammetry, differential pulse voltammetry and elemental analysis. For some compounds single crystals appropriated to X-ray diffraction analysis were obtained, leading to a valuable structural study. Specifically, in this work the mer-[RuCl3(NO)(P-P)], P-P = diphosphine, series was synthesized by the photochemical isomerization of the corresponding fac isomers in CH2Cl2 solution or in the solid state. The synthesis and NMR characterization of the mer-[RuCl3(15NO)(dppb)] allowed the correct attribution of the signal corresponding to each phosphorus in the 31P{1H} NMR spectra of the mer series. The electrochemical study shows that the oxidation/reduction processes observed in these complexes are dependent on both, the isomer (fac or mer) and the solvent. In CH2Cl2 the NO+ reduction potentials are less negative for the mer-isomers than for the fac, while in CH3CN these potentials are, in general, very close for both isomers. The reactions products of the fac-[RuCl3(NO)(P P)], P P = dppe or c-dppen, with the 4,6-dimethyl-2-mercaptopyrimidine ligand in methanol were the nitrosyl [Ru( SpymMe2 ,-N,-S)( SpymMe2 ,-S)(NO)(P P)]PF6, these were the first ruthenium complexes containing the nitrosyl and a pyrimidine derivative ligands. For these species, the cyclic voltammograms showed the first NO+ reduction reversible at @ -0.35 V and an irreversible process for the second reduction at @ -1.1 V. The trans-[RuCl(NO)(dppe)2]2+ complex had its photochemical behavior evaluated at 355 nm in CH3CN NO labilization (confirmed by a selective electrode) and formation of RuII and RuIII species identified by 31P{1H} NMR and EPR, respectively, were found. The same photochemical experiment carried out in CH2Cl2 produced species containing the RuII-NO0 unit as well as RuIII that were identified by EPR. With the same compound NO labilization was obtained with 520 nm irradiation by utilizing rhodamine B as sensitizator. The NO+ character of the trans-[RuCl(NO)(P-P)2]2+, P-P = dppe or c-dppen, complexes was evaluated by the reaction with the azide nucleophile in CH3CN forming the corresponding solvento derivatives. Complexes with general formula [RuCl(NO)(dcpe)(NN)] 2+, N-N = bipy, Me-bipy or phen, were synthesized and characterized showing an nNO close to 1890 cm-1 and a reversible pair NO+/NO0 with E1/2 close to 0.1 V. The geometry of these complexes were determined by the 31P{1H} NMR spectrum of the [RuCl(15NO)(dcpe)(bipy)]2+ species that showed one of the phosphorus trans to the NO, consequently the other one is trans to nitrogen. It was also shown that these complexes are attacked by the azide ion and that photo-induced NO labilization occurs in CH3CN when solutions are exposed to white light.