VALERIA DE FALCO CAPARBO
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Clínica Médica, Faculdade de Medicina
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
LIM/17 - Laboratório de Investigação em Reumatologia, Hospital das Clínicas, Faculdade de Medicina
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
LIM/17 - Laboratório de Investigação em Reumatologia, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
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- Effect of dexamethasone on human osteoblasts in culture: involvement of beta 1 integrin and integrin-linked kinase(2011) NAVES, Marcelo A.; PEREIRA, Rosa M. R.; COMODO, Andreia N.; ALVARENGA, Erika L. F. C. de; CAPARBO, Valeria F.; TEIXEIRA, Vicente P. C.Adhesive interactions play a critical role in cell biology, influencing vital processes from proliferation to cell death. Integrins regulate cell-ECM (extracellular matrix) adhesion and must associate with phosphorylating proteins such as ILK (integrin-linked kinase). Dysregulation of ILK expression is associated with anchorage-independent growth, cell survival and inhibition of apoptosis. Glucocorticoids influence differentiation and adhesion of osteoblasts and can affect bone protein synthesis. The objective of this study was to analyse the effect of DEX (dexamethasone) on the biology of osteoblasts, together with its influence on the expression of ILK and beta 1 integrin. For this, primary cultures of human osteoblasts were exposed to DEX at 10(-9) M (physiological dose) and 10(-6) M (pharmacological dose) for 24 and 48 h. Cell viability, apoptosis and cell adhesion were analysed, as well as protein expression of beta 1 integrin and ILK. It was observed that cell viability and adhesion were reduced in the cultures evaluated. In comparison with the control cultures, there was slightly less apoptosis in the cultures exposed to the physiological dose and considerably more apoptosis in those exposed to the pharmacological dose. In all treated cultures, protein expression of ILK was slightly higher than in the control cultures, whereas that of beta 1 integrin was significantly lower. Both proteins under study were co-localized at the cell periphery in all cultures. Our results suggest that DEX causes osteoblast anoikis, probably due to decreased beta 1 integrin expression, which might have had a direct influence upon ILK, reducing its activation and preventing it from playing its characteristic antiapoptotic role.
- Low bone mass in juvenile onset sclerosis systemic: the possible role for 25-hydroxyvitamin D insufficiency(2011) SHINJO, Samuel Katsuyuki; BONFA, Eloisa; CAPARBO, Valeria de Falco; PEREIRA, Rosa Maria RodriguesJuvenile onset systemic sclerosis (JoSSc) is a rare disease, and there are no studies focusing in bone mineral density and biochemical bone parameters. Ten consecutive patients with JoSSc and 10 controls gender, age, menarche age, and physical activity matched were selected. Clinical data were obtained at the medical visit and chart review. Laboratorial analysis included autoantibodies, 25-hydroxyvitamin D (25OHD), intact parathyroid hormone, calcium, phosphorus, alkaline phosphatase and albumin sera levels. Bone mineral density was analyzed by dual-energy X-ray absorptiometry, and bone mineral apparent density (BMAD) was calculated. A lower BMAD in femoral neck (0.294 +/- A 0.060 vs. 0.395 +/- A 0.048 g/cm(3), P = 0.001) and total femur (0.134 +/- A 0.021 vs. 0.171 +/- A 0.022 g/cm(3), P = 0.002) was observed in JoSSc compared to controls. Likewise, a trend to lower BMAD in lumbar spine (0.117 +/- A 0.013 vs. 0.119 +/- A 0.012 g/cm(3), P = 0.06) was also found in these patients. Serum levels of 25OHD were significantly lower in JoSSc compared to controls (18.1 +/- A 6.4 vs. 25.1 +/- A 6.6 ng/mL, P = 0.04), and all patients had vitamin D insufficiency (< 20 ng/mL) compared to 40% of controls (P = 0.01). All other biochemical parameters were within normal range and alike in both groups. BMAD in femoral neck and total femur was correlated with 25OHD levels in JoSSc (r = 0.82, P = 0.004; r = 0.707, P = 0.02; respectively). We have identified a remarkable high prevalence of 25OHD insufficiency in JoSSc. Its correlation with hip BMAD suggests a causal effect and reinforces the need to incorporate this hormone evaluation in this disease management.
- No deleterious effect of low dose methotrexate on titanium implant osseointegration in a rabbit model(2011) CARVAS, Janaina Badin; PEREIRA, Rosa Maria Rodrigues; BONFA, Eloisa; SILVEIRA, Celey Aparecida; LIMA, Luiz Lapa; CAPARBO, Valeria de Falco; MELLO, Suzana Beatriz Verissimo deOBJECTIVE: To evaluate the effect of low dose methotrexate alone or in combination with glucocorticoid treatment on titanium implant osseointegration. METHODS: Groups of 6-8 adult New Zealand White rabbits were treated for 18 weeks with saline (control), methotrexate, glucocorticoid, or methotrexate plus glucocorticoid. The animals received a titanium implant in the tibia at week 6. Lumbar spine and tibia bone mineral densities were analyzed before and after treatment. Histomorphometric analysis of bone cortical thickness, total bone area around the implant, and % of bone to implant contact was performed. RESULTS: After 18 weeks, the change in the bone mineral density in the lumbar spines and tibias in the methotrexate group was comparable to the control group (0.035 vs. 0.055 g/cm(2) and 0.021 vs. 0.041 g/cm(2), respectively). In contrast, both the glucocorticoid group and glucocorticoid plus methotrexate group had significant reductions at both sites. Histomorphometric analysis of the tibia in the control and methotrexate groups revealed no significant changes in cortical thickness (133 vs. 126 mu m), total bone area around the implant (33 vs. 30%), or bone to implant contact (40 vs. 38%). In contrast, glucocorticoid group had significant reductions compared to controls in tibia cortical thickness (99 vs. 133 mu m), total bone area around the implant (24 vs. 33%), and bone to implant contact (27 vs. 40%). Similar reductions were observed in the glucocorticoid plus methotrexate group. CONCLUSIONS: Our results demonstrate that low dose methotrexate treatment does not affect titanium implant osseointegration, suggesting that this therapy is safe for surgical procedures requiring a titanium implant.
- Prevalence and risk factors of radiographic vertebral fracture in Brazilian community-dwelling elderly(2011) LOPES, J. B.; DANILEVICIUS, C. F.; TAKAYAMA, L.; CAPARBO, V. F.; MENEZES, P. R.; SCAZUFCA, M.; KUROISHI, M. E.; PEREIRA, R. M. R.The prevalence and risk factors of radiographic vertebral fracture were determined among Brazilian community-dwelling elderly. Vertebral fractures were a common condition in this elderly population, and lower hip bone mineral density was a significant risk factor for vertebral fractures in both genders. The aim of the study was to estimate the prevalence of radiographic vertebral fracture and investigate factors associated with this condition in Brazilian community-dwelling elderly. This cross-sectional study included 943 elderly subjects (561 women and 382 men) living in So Paulo, Brazil. Thoracic and lumbar spine radiographs were obtained, and vertebral fractures were evaluated using Genant's semiquantitative method. Bone mineral density (BMD) was measured by dual X-ray absorptiometry, and bone biochemical markers were also evaluated. Female and male subjects were analyzed independently, and each gender was divided into two groups based on whether vertebral fractures were present. The prevalence of vertebral fracture was 27.5% (95% CI 23.8-31.1) in women and 31.8% in men (95% CI 27.1-36.5) (P = 0.116). Cox regression analyses using variables that were significant in the univariate analysis showed that age (prevalence ratio = 1.03, 95% CI 1.01-1.06; p = 0.019) and total femur BMD (PR = 0.27, 95% CI 0.08-0.98; p = 0.048) were independent factors in predicting vertebral fracture for the female group. In the male group, Cox regression analyses demonstrated that femoral neck BMD (PR = 0.26, 95% CI 0.07-0.98; p = 0.046) was an independent parameter in predicting vertebral fractures. Our results suggest that radiographic vertebral fractures are common in Brazilian community-dwelling elderly and that a low hip BMD was an important risk factor for this condition in both genders. Age was also significantly correlated with the presence of vertebral fractures in women.
- Osteoporotic Fractures in the Brazilian Community-Dwelling Elderly: Prevalence and Risk Factors(2011) LOPES, Jaqueline B.; FIGUEIREDO, Camille P.; CAPARBO, Valeria F.; TAKAYAMA, Liliam; MENEZES, Paulo R.; SCAZUFCA, Marcia; PEREIRA, Rosa M. R.The risk of osteoporotic fractures is known to vary among populations. There are no studies analyzing concomitantly clinical, densitometric, and lab risk factors in miscigenated community-dwelling population of Brazil. A total of 1007 elderly subjects (600 women and 407 men) from Sao Paulo, were evaluated using a questionnaire that included risk factors for osteoporotic fractures. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry at the hip and lumbar spine. Laboratory blood tests were also obtained. The prevalence of osteoporotic fractures was 13.2% (133 subjects), and the main fracture sites were distal forearm (6.0%), humerus (2.3%), femur (1.3%), and ribs (1.1%). Women had a higher prevalence (17.5%; 95% confidence interval [CI]: 14.6-20.6) than men (6.9%; 95% CI: 4.4-9.3) (p < 0.001). After adjusting for significant variables, logistic regression revealed that female gender (odds ratio [OR] = 2.7; 95% CI; 1.6-4.5; p < 0.001), current smoking (OR = 1.9; 95% CI: 1.2-3.3; p = 0.013), and the femoral neck T-score (OR = 0.7; 95% CI: 0.5-0.9; p = 0.001) remain significant risk factors for osteoporotic fractures in the community-dwelling elderly. Our findings identified that female gender, current smoking, and low hip BMD are independent risk factors for osteoporotic fractures.