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This study was developed based on in vivo investigation of microporous granular biomaterials based on calcium phosphates, involving matrices of ß-tricalcium phosphate (ß-TCP), hydroxyapatite (HA), biphasic compositions of both phases and a control group. The physicochemical characterization of materials was carried out by X-Ray diffraction (DRX) and mercury porosimetry. Biodegradability, bioactivity and neoformation processes were investigated by Raman spectroscopy, scanning electron microscopy (SEM) and polarized light conducted on biopsies obtained from in vivo tests for periods of 90 and 180 days. These were performed to evaluate the behavior of granular microporous compositions in relation to bone neoformation. Through the performance obtained from in vivo assays, excellent osseointegration and bone tissue neoformation were observed. The results are encouraging and show that the microporous granular biomaterials of HA, ß-TCP and biphasic compositions show similar results with perfect osseointegration. Architectures simulating a bone structure can make the difference between biomaterials for bone tissue replacement and repair.

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Calcium phosphates (CAPs) can be produced from either biologically sourced materials or mineral deposits. The raw materials impart unique properties to the CAPs due to innate trace amounts of elements that affect the crystal structure, morphology and stoichiometry. Using calcium carbonate (CaCO3) precursors derived from fossilized calcareous marine sediments (FCMSs), we have synthesized a novel class of CAP biomaterials, termed fm-CaPs, with defined Ca/P molar ratios of 1.4 and 1.7 using a wet synthesis method. Compared with commercially available CAP biomaterials, such as hydroxyapatite (HA) and beta-tricalcium phosphate (ß-TCP), fm-CaP1.7 had a biphasic composition consisting of an HA phase (in a hexagonal system) and a ß-TCP phase (in a rhombohedral crystalline system), which is desirable for the current design of bone substitutes, whereas fm-CaP1.4 consisted of an HA phase and a beta-dicalcium pyrophosphate phase (in a tetragonal system). These bioceramics exhibited a fringe structure of regular crystallographic orientation with well-ordered mesoporous channels. The FCMS raw material imparted trace amounts of silicon (Si), strontium (Sr) and zinc (Zn) to fm-CaPs; these are elements that are important for bone formation. The cyto-compatibility of these biomaterials and their effects on cellular activity were evaluated using osteoblast cells. Cell proliferation assays revealed no signs of cytotoxicity, whereas cells growth was equal to or better than HA and ß-TCP controls. The SEM analysis of the cell and material interactions showed good cell spreading on the fm-CaP materials that was comparable to ß-TCP and in vitro assays suggested robust osteogenic differentiation, as seen by increased mineralization (alizarin red) and upregulation of osteogenic gene expression. Our results indicate that fm-CaP1.7, in particular, has chemical, physical and morphological properties that make this material suitable for applications that promote bone tissue regeneration.

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É apresentado um caso de paraganglioma gangliocítico da região da papila duodenal em paciente masculino de 51 anos, com queixa de dor epigástrica e empachamento pós-prandial. O paraganglioma gangliocítico é neoplasia rara no trato gastrointestinal, onde o local mais acometido é a região periampular do duodeno. A constituição por três tipos celulares permite sua identificação bem como diagnóstico diferencial com outros tumores um pouco mais comuns no local, como o carcinóide duodenal, o ganglioneuroma e o tumor estromal gastrointestinal (GIST).

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PURPOSE: To show the author's experience with percutaneous transluminal coronary angioplasty (PTCA) in patients with prior coronary bypass surgery. METHODS: Between January 1989 and January 1991, 629 PTCA in 572 patients were performed. Forty-eight had previous revascularization surgery with interval range of 4 days to 10 years. The PTCA sites were divided in three groups: A) native arterial segments, not affected by surgery (26 patients); B) native arterial segments proximal (4 patients) and distal (2 patients) to graft anastomosis; C) in the coronary vein graft (16 patients). RESULTS: The overall primary success was 78%. In groups B and C, 16 procedures were successfully dilated (72%). All failures in group C were due to unstable problems in reaching (4 patients) or crossing (2 patients) the stenosis with the balloon. There was one death in group A and another in group C. CONCLUSION: Angioplasty is an effective alternative for treatment of recurrent ischemia in patients with prior myocardial revascularization surgery and in early results are comparable to the general angioplasty population.

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The authors describe the epidemiological findings related to human taeniasis and cysticercosis, and swine cysticercosis in two small rural communities, Postinho (P) and Tigre (T), of South Brazil. The prevalence of epilepsy was 2.04% (P) and 2.25% (T). The prevalence of neurocysticercosis was 0.47% (P) and 0.93% (T), and prevalence of swine cysticercosis was 12.8% (P) and 27.8% (T). Taenia sp. infestation was detected in 4.3% (P) and 4.6% (T) of stool examinations. The hyperendemic human taeniasis and cysticercosis and swine cysticercosis seems to be related to poor hygienic habits of the population, and the free access to human excreta by the pigs.

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PURPOSE: To show the initial experience of this service with the technique of percutaneous transluminal coronary angioplasty. PATIENTS AND METHODS: Between january 1988 and december 1989, 305 coronary angioplasties were performed in 280 patients with age range of 33 to 82 years (being 49% above 60 years old) and 71% male. Among those, 212 (75%) experienced clinical picture of stable angina and 68 (25%) of unstable angina or myocardial infarction. Patients were divided in three groups: group A--those with lesions of 70% or worse in more than one vessel or in the same vessel with or without any other vessel total occlusion (multiple lesions or multiple vessels: 36 patients; group B--those with lesions of 70% or worse in one vessel with at least one occluded vessel: 64 patients; group C--those with lesions of 70% or worse isolated in a single vessel: 180 patients. RESULTS: Of the 280 treated patients, 229 were considered successful (75%). There has been 22 complications (7%) and 9 deaths (3%). The late follow-up (from 1 to 24 months), displayed 28 new procedures based on clinical suspicion of restenosis. Obstruction or occlusion were present in 16 of the later, with 10 being selected to undergo new procedure, one of those twice. The remaining 12 patients received clinical or surgical treatment. CONCLUSION: Aside from the fact that early and midterm results indeed are promising, the procedure is not safe from immediate risks, and limiting late restenosis. Nevertheless, the lesions might be redilated by the same technique, with success rates comparable to the initial one.

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Se exponen los índices infección obtenidos con paracoccidioidina y su correlación con distintas zonas climáticas de la Provincia del Chaco, República Argentina; se observaron los mayores porcentajes (21,3%) en la localidad de Juan José Castelli, del sector occidental, sub región semiárida de la provincia

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Se exponen los índices infección obtenidos con paracoccidioidina y su correlación con distintas zonas climáticas de la Provincia del Chaco, República Argentina; se observaron los mayores porcentajes (21,3%) en la localidad de Juan José Castelli, del sector occidental, sub región semiárida de la provincia (AU)

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