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Orientador: Adil Muhib Samara / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-12T15:20:38Z (GMT). No. of bitstreams: 1 Mardegan_LucianaCalvo_M.pdf: 1133557 bytes, checksum: 3724bd20274a4ec0c0d6a02b0da7547d (MD5) Previous issue date: 2008 / Resumo: No Brasil, a prevalência da osteoartrite é de cerca de 16,2%, sendo que aos 75 anos, 85% das pessoas apresentarão evidências clínica ou radiológica da doença. A condrocalcinose é a segunda principal causa de doença por deposição de cristais. Estudos recentes têm demonstrado uma prevalência de 8-10% de condrocalcinose radiológica em pacientes com 60 anos ou mais. Nosso objetivo é avaliar a influência dos cristais de pirofosfato de cálcio na osteoartrite inflamatória de joelhos. Foram avaliados vinte pacientes do Ambulatório de Ortopedia do Hospital de Clínicas da Unicamp, com critérios diagnóstico de osteoartrite em joelhos. Realizaram-se exames de imagem (radiografia, tomografia computadorizada e ressonância nuclear magnética), colheita do líquido sinovial com posterior análise por microscopia de luz compensada e polarizada, além da dosagem de cálcio no dia da colheita e noventa e seis horas após. Os achados foram correlacionados com a presença ou não de osteoartrite inflamatória. Entre os vinte pacientes estudados, onze apresentavam osteoartrite inflamatória, sendo que a condrocalcinose foi evidenciada na radiografia, tomografia e na ressonância de um paciente e apenas na tomografia de outro. Entre os nove que não apresentavam osteoartrite inflamatória, apenas um apresentou imagem de condrocalcinose na tomografia. Foi dosado o cálcio no LS de quinze pacientes, sendo que não houve diferença significativa entre a média do cálcio 1 e cálcio 2. Não foi possível estabelecer a relação entre a presença de cristais de pirofosfato de cálcio e a osteoartrite inflamatória de joelhos / Abstract: Objective: Osteoarthritis prevalence in Brazil is around 16, 2%, and, by the age of 75, 85% of the individuals will present with clinical or radiological signs of the disease. Chondrocalcinosis is the second cause of crystal deposition pathology. Recent studies show 8-10% of radiologic evidence of chondrocalcinosis in people older than 60 years. Our goal is to evaluate the impact of calcium pyrophosphate crystals on inflammatory knee osteoarthritis. Methods: Twenty patients from UNICAMP Clinical Hospital, Orthopedic clinic, with complains of knee joint pain were assessed. Image exams (Radiography, TC scan and Magnetic Resonance Imaging), synovial liquid exam (polarized compensated light microscopy and calcium quantification at the same day of synovial liquid aspiration and after 96 hours) were performed. The diagnosis of inflammatory osteoarthritis was given according to these findings. Results: Eleven patients, among the initial twenty, presented inflammatory osteoarthritis and chondrocalcinosis was observed in two of them. Chondrocalcinosis was detected by Rx, TC scan and MRI in one and just by TC in the other. As for the other nine subjects, just one presented chondrocalcinosis on TC scan. There was no difference regarding synovial liquid calcium measurements. Conclusion: It was not possible to establish a correlation between calcium pyrophosphate crystals and knee osteoarthritis / Mestrado / Clinica Medica / Mestre em Clinica Medica

Ph.D. (Chemistry) / The effect of crystal defects on the adsorption and flotation properties of zinc sulphides was examined. Flotation experiments were restricted to collectorless flotation, that is to the flotation of untreated and copper-activated samples. The effect of cyanide treatment was examined only so that an explanation could be found for the bonding characteristics of the adsorbed copper on regions where the crystallography was undisturbed and on those where it was distorted. The electrochemical method for the determination of copper permitted continuous and highly sensitive monitoring of the copper adsorption on the sphalerites. The first part of the thesis concerns the adsorption of copper on synthetic zinc sulphide crystals and natural sphalerites. It is stated that the degree of adsorption depends on the defect structure. Structure etching, gamma-ray irradiation, and selective grinding experiments are shown to justify the conclusions reached. The second part of the thesis describes the flotation of the samples. The adsorption characteristics of the samples are defined in the first part and the adsorption and flotation properties are correlated.

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The introduction contains introductory remarks on scintillation counters together with a brief description of the exciton theory believed to be the means of primary energy migration within organic crystals. Part I contains a review of the data published on the reletive responses of different organic crystals and the attempted correlations of these results with the molecular structures of the different phosphors. From data which may be accepted as being both reliable and suitable for comparison it is concluded that theories involving correlations between phosphor efficiencies and molecular structures may be tested only if the efficiency data has (i) been extrapolated to give results for crystals of very small thickness and {ii) been obtained at very low temperatures. Part II contains accurate calculations based on the exciton theory proposed by Birks (1951 ) to account for the response of crystals to different types of ionising radiations. Satisfactory agreement is obta1ned with all the avalable experimental data in the literature. In part III an account is given of the response of organic crystals observed by the author for low-energy ⋉particles, and of the similar behaviour found by Taylor et al, (1951 ) for low-energy electrons. A possible extension of the theory described in part II, allowing for the escape of excitons through the crystal surface is given accounting for this behaviour. An exciton mean free path in anthracene, terphenyl and stilbene of about 3 - 7/u is obtained. Results were obtained with strong ⋉-particle sources which could not be explained. in terms ot normal response of the phosphor used. This effect was inventigatea as described in part IV, and it is shown that photons are produced in air, glass and quartz when these materials are irradiated by ⋉particles. This luminescence was probably responsible for the "scintillations" which Richards and Cole (1951) have ascribed to thin films of various materials. Problems requiring further investigation are indicated.

The work described in this thesis was performed at the Physics Department, Rhodes University during 1958 and 1959 under the supervision of Professor J.A. Gledhill. Use was made of a vacuum ultra-violet spectrograph which had been constructed in the Physics Department (1.1) and modifications to be described were made to this instrument. The instrument was used for studying the effects of oxygen on the fluorescence excitation spectrum of Anthracene.

A nonuniform annealing rate of color centers in LiF is attributed to a nonuniform density of dislocations which, in turn, is a direct consequence of the cleaving process. The tensile deformation properties of annealed LiF crystals were determined over the temperature range – 196 ⁰C. to +60 ⁰C. Several tests were also carried out on ɣ - irradiated specimens at ambient temperatures. A transition occurs in the work hardening rate during stage II deformation. Experiments involving both strain-rate and temperature cycling were performed over the limited temperature range of - 60 to +60 ⁰C. The results were analyzed in terms of rate theory expressions and indicated that the rate controlling mechanism for dislocation motion in stage IIA is probably the nonconservative motion of jogs in screw dislocations. Stage IIB hardening is more likely controlled by dislocation intersections. Evidence is presented which indicated that stress relaxation experiments may provide an extremely easy technique for the determination of the internal flow stress. Values obtained from such experiments on LiF agree remarkably well with those obtained from rate theory experiments. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate