Avaliação das metaloproteinases de matriz -2 e -9 em gatos com desmineralização óssea secundária à tirotoxicose induzida

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação do potencial genotóxico do extrato bruto de Pyrostegia venusta (Ker Gawl.) Miers, Bignoneaceae, em medula óssea de camundongos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência do cetoprofeno na consolidação óssea de ulnas osteotomizadas de coelhos: estudo qualitativo e quantitativo através de programas computacionais

OBJETIVO: Acompanhar o processo de consolidação óssea de ulnas osteotomizadas de coelhos tratados com cetoprofeno, por meio de programas computacionais. MÉTODOS: Os coelhos foram submetidos a osteotomia da ulna e divididos em dois grupos. No grupo A (n=10) os animais foram tratados com cetoprofeno (2mg.kg-1) durante cinco dias. O grupo B (n=5) serviu como controle. Os animais foram radiografados um dia após a operação e a cada 7 dias até perfazer 28 dias. No ato da tomada radiográfica, junto à região a ser estudada, foram colocadas uma escada e uma cunha de alumínio que serviram como referencial de densidade óptica. As imagens radiográficas foram digitalizadas através de um scanner. O programa ODR forneceu imagens tridimensionais e coloridas. Outro programa, CROMOX, avaliou a densidade mineral óssea da região da ostetotomia. RESULTADOS: As imagens fornecidas pelo ODR proporcionaram melhor visualização da lesão e do processo de consolidação óssea. O programa CROMOX forneceu uma análise quantitativa ao calcular a densidade mineral do calo ósseo formado ao longo dos 28 dias de observação. Não houve diferença estatisticamente significante entre os valores de densidade mineral óssea das ulnas osteotomizadas dos coelhos tratados com cetoprofeno e do grupo controle, nas radiografias realizadas ao longo de 28 dias de pós-operatório. CONCLUSÃO: O cetoprofeno não interferiu no processo de formação do calo ósseo de ulnas osteotomizadas de coelhos.

Assessment of bovine biomaterials containing bone morphogenetic proteins bound to absorbable hydroxyapatite in rabbit segmental bone defects

OBJETIVO: Avaliar a capacidade osteo-regenerativa de dois biomateriais utilizando um modelo de defeito segmentar efetuado nas diáfises do rádio de coelhos. MÉTODOS: O defeito direito foi preenchido com pool de proteínas morfogenéticas ósseas (pBMPs) e hidroxiapatita em pó ultrafina absorvível (HA) combinada com matriz óssea inorgânica desmineralizada e colágeno, derivados do osso bovino (Grupo A). O defeito esquerdo foi preenchido com matriz óssea desmineralizada bovina com pBMPs e hidroxiapatita em pó ultrafina absorvível (Grupo B). em ambos os defeitos utilizou-se membrana reabsorvível de cortical bovina desmineralizada para reter os biomateriais no defeito ósseo e guiar a regeneração tecidual. Os coelhos foram submetidos à eutanásia aos 30, 90 e 150 dias após a cirurgia. Foram efetuados exames radiográficos, tomográficos e histológicos em todos os espécimes. RESULTADOS: Aos 30 dias de pós-cirúrgico, o osso cortical desmineralizado foi totalmente reabsorvido em ambos os grupos. A HA tinha reabsorvido nos defeitos do Grupo A, mas persistiu nos do Grupo B. Uma reação de corpo estranho foi evidente com ambos os produtos, porém mais pronunciada no Grupo B. Aos 90 dias os defeitos do grupo B tinham mais formação óssea que os do Grupo A. Entretanto, aos 150 dias após a cirurgia, nenhum tratamento havia promovido o completo reparo do defeito. CONCLUSÃO: Os biomateriais testados contribuíram pouco ou quase nada para a reconstituição do defeito segmentar.

Valores normais da densidade mineral óssea do acessório do carpo em eqüinos da raça Brasileiro de Hipismo (BH) determinados por meio da densitometria óptica em imagem radiográfica

Com o objetivo de estabelecer os valores normais da densidade mineral óssea (DMO) em milímetros de alumínio (mmAl) de eqüinos da raça Brasileiro de Hipismo (BH), foi radiografado o osso acessório do carpo de animais desta raça e aplicada a técnica da densitometria óptica em imagem radiográfica (DOR). Foram utilizados animais de 20 a 30 meses de idade, sendo 12 machos e 12 fêmeas. A DMO média foi de 4,7 ± 0,1mmAl para os machos e de 4,6 ± 0,1mmAl para as fêmeas, não sendo significativa a diferença entre estes valores.

Determinação da densidade mineral óssea da extremidade distal do rádio-ulna em gatos: correlação entre peso, sexo e idade

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Alguns eventos morfológicos do processo de reparo de falha óssea diafisária no rádio esquerdo de ratos tratados com fenobarbital

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Regeneração da vegetação arbórea nativa no sub-bosque de um povoamento de Eucalyptus saligna Smith. Localizado no Estado de São Paulo

This study evaluate the native species naturally regenerating in Eucalyptus saligna stand understory. This stand is located at Itatinga Experimental Station, of the Forest Sciences Department (ESALQ/USP). The experimental area encompasses two sites separated from each other around 250 m, differing 30 m in altitude. These two sites are different mainly in land slope and soil fertility and soil hydric retention capacity. Eight permanent plots of 625 m2 in each site were randomly sampled. The woody species Individuals with height equal or bigger than 1,5 m and the Eucalyptus saligna coppicings were surveyed in each plot. A total of 107 species were Identified and 7 species were common to both sites, distributed into 72 genera and 34 families. Based upon the results It is possible to conclude that the Eucalyptus saligna trees do not preclude the natural regeneration of the native species in the stand understory, however the floristic structure of the community is also influenced by edaphic factors and vicinity of seed sources.

Isolamento de células-tronco mesenquimais da medula óssea

Mesenchymal Stem Cells (MSCs) have a high ability to renew and differentiate themselves into various lineages of conjunctive tissues. This study aimed to isolate the MSCs from murine bone marrow by using two different growth media and to characterize them with immunostaining with antivimentin antibody. We used six 2-week old BALB/c mice. Bone marrow was collected from mice's tibial and femoral channels and re-suspended in a final strength of 6x105 in Knockout-DMEM and high-glucose-DMEM media, supplemented by 10% FBS, and kept in a humidified 5% CO2 incubator at 37°C for 72 h, when non-adherent cells were removed during the change of medium. The number and density of adherent fibroblast-like colonies was greater with the Knockout-DMEM medium (within 5 days of culture) versus 10-20 days in DMEM-high glucose to get the same cellular concentration. The cells in both groups were highly positive for antivimentin antibody, characterizing them as MSCs. Obtaining MSCs as quickly as possible is essential for cell therapy field, especially when those cells are intended to be used for the repair of tissues from mesenchymal sources.

Determinação de desmineralização óssea em gatos após tirotoxicose experimental

Hyperthyroidism can result in serious effects on the bone metabolism in humans as well as animals. For a better characterization of thyrotoxicosis effects, 16 cats were induced into thyrotoxicosis by intaking a dose of 150 μg/kg of sodium L-thyroxine every 24 hours during 42 days. The hormonal levels were evaluated by radioimmunoassay technique and the bone mineral density of the right distal radius extremity was measured through the radiographic optical densitometry. Was verified significant bone demineralization seven days of hormonal intake as weel as radius demineralization.

Dinâmica da regeneração do subsolo de áreas degradadas dentro do bioma Cerrado

The objective of this research was to evaluate the physical and chemical conditions of revegetated subsoil in degraded areas in a Cerrado biome and to verify which plants promote better conditions for soil recovery. The research was conducted in the remaining area of the hydroelectrical plant site at Ilha Solteira (SP). The experimental design was a completely randomized with five treatments and three replications. The treatments consisted of: natural regeneration area, brachiaria area, Pinus sp. area, exposed soil area and Cerrado grassland (used as control). The following soil characteristics were appraised: porosity; density, stability of aggregates, infiltration rate, temperature, exchangeable cations, organic matter, pH and potential acidity. The results show that Pinus is not a good species to recover the chemical attributes of the subsoil. The revegetated areas need to be improved in their physical attributes to allow a better development of the vegetation. Brachiaria and the natural regeneration were the most promising treatments, presenting results similar to natural Cerrado.

Os efeitos de um programa de atividade física de carga progressiva nas propriedades físicas e na força óssea de ratas osteopênicas

Background: Many studies have shown that physical exercises are able to stimulate bone formation and increase bone mass, constituting a therapeutic modality to treat bone loss due to osteoporosis. However, some points about the intensity, duration and frequency of the exercises remain confusing and contradictory. Thus, the aim of this study was to determine the effects of a progressive loading exercise program on femur of osteopenic rats. To induce osteopenia we used the animal model of ovariectomy (OVX). Forty animals was studied and divided into 4 groups: sham-operated sedentary (SS); ovariectomy-sedentary (OS); sham-operated training (ST) and ovariectomy training (OT). The trained groups performed jumps into water: 4 series of 10 jumps each, with an overload of 50% to 80% of the animal's body weight, during 8 weeks. Femora were submitted to a physical properties evaluation, a biomechanical test, calcium and phosphorus content measurement and a morphometric histological evaluation. Results: osteopenic animals showed a decrease of bone strength and lower values of bone weights, bone density and calcium content. The exercised osteopenic rats showed higher values of geometrical, physical properties, bone strength and calcium content compared to controls. The results of the present study indicate that the progressive loading exercise program had stimulatory effects on femora of osteopenic rats. It seems that the intensity and duration of the protocol used produced bone structural adaptations, which contributed to reverse bone loss due to ovariectomy.

Diferenciação hepatocítica de células-tronco mesenquimais da medula óssea humana

Some recent articles have reported that mesenchymal stem cells (MSCs) can be induced to express hepatocyte markers by transplanting them into animal models of liver damage, or by in vitro culture with growth factors and cytokines. In this study, the aim is to evaluate the behavior of MSCs subjected to induction of hepatocyte differentiation. The MSCs were isolated from the bone marrow of 4 normal donors, characterized and subjected to both in vitro and in vivo induction of hepatocyte differentiation. The in vitro induced cells showed morphological changes, acquiring hepatocyte-like features. However, the immunophenotype of these cells was not modified. The induced cells exhibited no increase in albumin, cytokeratin 18 or cytokeratin 19 transcripts, when analyzed by real-time RT-PCR. The expression of albumin, cytokeratin 18 and alpha fetoprotein was also unchanged, according to immunofluorescence tests. In vivo, the MSC demonstrated a potential to migrate to damaged liver tissue in immunodeficient mice. Taken together, the results suggest that bone marrow MSCs are incapable of in vitro differentiation into hepatocytes by the approach used here, but are capable of homing to damaged hepatic tissue in vivo, suggesting a role for them in the repair of the liver. This contribution to tissue repair could be associated with a paracrine effect exerted by these cells.

Efeito do cálcio na qualidade óssea e de ovos de poedeiras

The experiment was carried out, with hens of the Shaver Brown strain in production, during 27 weeks. The objective was to evaluate the mobilization of bone calcium and phosphorus for the formation of the shell eggs, as well as to follow the variations in the bone quality along the production cycle. 64 birds had been used. The experimental desing was entirely randomized with two treatments (calcium percentage in the diet) and four repetitions of eight birds each. The used diets were isoproteic and isoenergetic adequate (3.8%) and low (1.8%) calcium levels. Analysis of bone (tibiae and femurs) mineral density (DMO) were done at 16, 22, 28, 34 and 40 weeks of age were developed. After each radiographic collection, 4 birds/treatment, were abated for the analysis of bone resistance (RO), Seedor index (IS), dry matter (MS), total mineral (MIN) and calcium and phosphorus (Ca and P). The values of egg production, production of egg mass and quality of the egg shell were also evaluated. It was possible to conclude that the birds mobilized bone minerals for the egg production, independently of the treatment and the birds receiving diets with low levels of calcium had the quality of the eggs shell damaged.

Correlação entre a densidade mineral óssea e níveis séricos de cálcio, fósforo e fosfatase alcalina total em gatos após tirotoxicose experimental

Hyperthyroidism is and endocrinal dysfunction characterized by excessive serum concentrations of thyroid gland hormones, which can cause several effects on the bone tissue in humans and in animals. For a better characterization of thyrotoxicosis effects on bone metabolism, 16 cats were induced into hyperthyroid state. Results showed that, in some moments a major bone demineralization of the right distal radium estremity promoted an elevation of the serum levels of phosphorus and total alkaline phosphatase.