R.F Silva
Universidade Federal de Minas Gerais
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Veterinary and Comparative Orthopaedics and Traumatology | 2013
R.F Silva; Jorge U. Carmona; Cleuza Mf Rezende
OBJECTIVES The objective of this study was to evaluate by clinical, radiographic, and force plate gait analyses the effect of post-surgical intra-articular injections of autologous platelet concentrates (PC) in a small group of dogs with cranial cruciate ligament (CCL) rupture. METHODS The ten dogs used in this study were initially presented with CCL rupture and underwent ligament replacement surgery by fascia lata autograft guided by arthroscopy. Six dogs received three intra-articular injections of PC (PC group); one dose was injected immediately after surgery, and two additional doses were injected at two-week intervals. The remaining four dogs received only nutraceuticals (control group). All dogs were evaluated by clinical examination, serial radiography, and force plate gait analyses at monthly intervals up to 90 days. RESULTS The clinical follow-up of the PC-treated group indicated a better outcome than the control group. Radiographic evaluation was not conclusive. Values of peak vertical reaction force and vertical impulse of the affected limbs were only significantly larger on the 90th postoperative day in the PC group compared to the control group. CLINICAL SIGNIFICANCE Our results indicate that autologous PC might improve functional outcome after intra-articular cranial cruciate ligament repair. The effect of PC when using other repair procedures warrants additional studies.
Archivos De Medicina Veterinaria | 2011
R.F Silva; Cleuza Mf Rezende; F.O Paes-Leme; Jorge U. Carmona
SUMMARY The aim of this study was to evaluate a manual method for concentrating canine platelets and consequently produce autologous platelet concentrates (APCs) for clinical and experimental proposals. The APCs were obtained by venous blood collection in tubes with ACD solution and were spun at 191 g for 6 minutes. The cell counts of whole blood and APCs, were statistically different (P < 0.01) between the values for platelets, leukocytes, granulocytes, monocytes, but not for lymphocytes. A strong negative correlation (ρ = -0.702 P = 0.011) between the number of lymphocytes and platelets in the APCs was found. The collection efficiency of platelets was 29.9% and the concentration of platelets was 49.4% higher in APCs when compared to the whole blood samples. The results indicated that this simple centrifugation method allows concentrating canine platelets.
BMC Veterinary Research | 2012
R.F Silva; Jorge U. Carmona; Cleuza Mf Rezende
BackgroundThe clinical use of autologous platelet concentrates (also known as platelet-rich plasma) on the field of regenerative therapy, in the last decade has been the subject of several studies especially in equine medicine and surgery. The objectives of this study was: 1) to describe and compare the cellular population in whole blood, lower fraction (A) and upper fraction (B) of platelet concentrates, 2) to measure and compare the transforming growth factor beta 1 (TGF-β1) concentration in plasma and both platelet concentrates after be activated with calcium gluconate or batroxobin plus calcium gluconate and, 3) to determine correlations between cell counts in platelet concentrates and concentrations of TGF-β1. Blood samples were taken from 16 dogs for complete blood count, plasma collection and platelet concentrates preparation. The platelet concentrates (PC) were arbitrarily divided into two fractions, specifically, PC-A (lower fraction) and PC-B (upper fraction). The Platelet concentrates were analyzed by hemogram. After activated with calcium gluconate or batroxobin plus calcium gluconate, TGF-β1 concentration was determined in supernatants of platelet concentrates and plasma.ResultsThere were differences statistically significant (P < 0.05) for the platelet count and leukocyte count and TGF-β1 concentration between whole blood, plasma and both platelet concentrates. A significant correlation was found between the number of platelets in both platelet concentrates and TGF-β1 concentration. Platelet collection efficiency was 46.34% and 28.16% for PC-A and PC-B, respectively. TGF-β1 concentration efficiency for PC activated with calcium gluconate was 47.75% and 31.77%, for PC-A and PC-B, respectively. PC activated with batroxobin plus CG showed 46.87% and 32.24% for PC-A and PC-B, respectively.ConclusionsThe methodology used in this study allows the concentration of a number of platelets and TGF-β1 that might be acceptable for a biological effect for clinical or experimental use as a regenerative therapy in dogs.
BMC Veterinary Research | 2012
R.F Silva; María E. Álvarez; Diana L. Ríos; Catalina López; Jorge U. Carmona; Cleuza Mf Rezende
BackgroundThere are not reported regarding the protocols for obtaining platelet concentrates (PC) in cats for medical purposes. The objectives of this study were: 1) to describe a manual method for producing two kinds of PC in cats (PC-A and PC-B), 2) to describe the cellular population of the PC, 3) to measure and compare the effect of calcium gluconate (CG) and bovine thrombin (BT) on the temporal release of transforming growth factor beta 1 (TGF-β1) and platelet-derived growth factor type BB (PDGF-BB) at 3 and 12 hours post-activation and 4) to establish correlations between the cellular population of both PCs and the concentration of growth factors (GF). Blood samples were taken from 16 cats for complete blood count, plasma collection and PC preparation. The PC were arbitrarily divided into two fractions, specifically, PC-A (lower fraction) and PC-B (upper fraction).ResultsThe platelet counts were significantly different (P<0.05) between the PC and whole blood but not between the PC fractions. The TGF-β1 concentration efficiencies for PC-A and PC-B activated with CG were 42.86% and 46.54%, and activated with BT were 42.88% and 54.64%, respectively. The PDGF-BB concentration efficiencies for PC-A and PC-B activated with CG were 61.36% and 60.61%, and activated with BT were 65.64% and 72.12%, respectively. The temporal release of GFs showed no statistically significant difference (P>0.05) between the activating substances at the time or for any PC fraction.ConclusionsWhatever the activation means, these preparations of cat PC provide significant concentrations of platelets and GFs for possible clinical or experimental use.
Arquivo Brasileiro De Medicina Veterinaria E Zootecnia | 2012
R.F Silva; Jorge U. Carmona; C.M.F. Rezende
We report the case of a dog that received intra-articular injections of platelet-rich plasma (PRP) during the postoperative period of surgical treatment of cranial cruciate ligament (CCL) rupture. Clinical, and gait analysis by the force plate in this patient might suggest the use of intra-articular injections of PRP as a post-surgical therapy in the treatment of CCL rupture.
BMC Veterinary Research | 2013
R.F Silva; Jorge U. Carmona; Cleuza Mf Rezende
BackgroundThe aim of this study was to use transmission electron microscopy to describe the ultrastructural characteristics of clots obtained from canine and feline platelet concentrates (PC) that had been activated with calcium gluconate (CG) or CG plus batroxobin (CGB). Platelets from fibrin clots were classified according their morphological changes. The area of the intercellular space (μm2), the area of the fibrin fibers (μm2), and the width of the fibrin fibers (μm) were determined for the dog clots. The platelet area (μm2), the area of fibrin fibers (μm2), the ratio of the minor and major axes of platelets, the ratio of the major and minor axes of platelets, and the number of α-granules found within platelets were measured for the cat clots.ResultsCat platelets displayed full activation. Dog platelets displayed lysis with loss of normal architecture. In both species, a statistically significant difference was found (P < 0.01) between the fibrin fiber measurements in the PC clots activated with CG and CGB.ConclusionsThe findings suggest that activation with CG caused platelet alpha granules to release their contents. In cats, fibrin production was greater when the PC was activated with CG. In dogs, activation with CG produced thick fibrin fibers.
Arquivo Brasileiro De Medicina Veterinaria E Zootecnia | 2013
J.S. Lara; H.P. Oliveira; E.G.L. Alves; R.F Silva; C.M.F. Resende
The epidemiological profile, clinical signs, and surgical techniques used and the recovery of dogs presented for treatment of patellar luxation in the Veterinary Hospital of UFMG in the period from 2000 to 2010 were evaluated through a retrospective study. The clinical and surgical records of dogs and the data recorded for each animal were used. 342 joints in the records of 210 animals were studied. The congenital bilateral medial luxation was the most frequent occurrence and females were more affected. The age of the animals ranged from 32 days to 16 years, with higher incidence of luxation in animals under one year of age and body mass below 9.1kg. In 11.7% of the members had grade I luxation, 39.8% were grade II, 20.5% were grade III and 28% were grade IV. The frequency of preoperative claudicating was higher in dogs with luxation grades III and IV. Of the 342 joints, 218 underwent surgery. In the postoperative evaluation of animals, those with grade IV luxation showed higher claudicating frequency. The patellar luxation mainly affects females, and the bilateral congenital luxation is the most common occurrence, and young and small animals are more likely to have it. Functional recovery postoperative luxation in grade IV is slow and partial.
Archivos De Medicina Veterinaria | 2013
R.F Silva; Jorge U. Carmona; Cleuza Mf Rezende
Resumen es: Los objetivos de este estudio fueron describir los signos clinicos asociados con alteraciones de la marcha, y correlacionar los resultados del examen rad...
Archivos De Medicina Veterinaria | 2013
R.F Silva; Jorge U. Carmona; Cleuza Mf Rezende
RESUMEN La displasia del codo canino (CED) es un complejo de enfermedades que resultan en (OA) osteoartritis. CED incluye la no union del proceso anconeo (UAP), fragmentacion del proceso coronoides medial (FMCP), osteocondritis (OC) del condilo medial del humero e incongruencia del codo. Una perra con OC del condilo medial del humero y FMCP fue tratada por artroscopia mediante microfracturas del hueso subcondral y remocion, respectivamente, y recibio dosis intra-articulares de concentrados autologos de plaquetas (APC). La paciente fue evaluada mediante examen clinico, citologia del liquido sinovial, evaluacion radiografica y evaluacion en plataforma de fuerza, antes de la cirugia y a los 15, 30, 60 y 90 dias postoperatorios. La paciente alcanzo recuperacion clinica completa al 60 dia postoperatorio, acompanado de mejoria en la citologia del liquido sinovial y en los resultados cinematicos. Sin embargo, la evaluacion radiologica mostro un leve desarrollo de OA. Los resultados de este informe pueden sugerir el potencial de uso de APC como una terapia de accion modificadora sintomatica en el tratamiento de OA secundaria a la displasia de codo en el perro.
Archivos De Medicina Veterinaria | 2013
R.F Silva; G.C Santana; F.O.P Leme; Jorge U. Carmona; Cleuza Mf Rezende
Los objetivos de este estudio fueron: 1) medir las concentraciones del factor de crecimiento transformante beta 1 (TGF-β1 y factor de crecimiento derivado de las plaquetas tipo AB (PDGF-AB) en plasma y gel de plaquetas (PG) activados con sales de calcio (gluconato o cloruro) en caninos, y 2) determinar las correlaciones entre los resultados celulares y la concentracion de factores de crecimiento (GF). Se colectaron muestras de sangre de catorce perros Fila brasilero. Para obtener sangre entera y plasma se utilizo EDTA y para preparar los concentrados de plaquetas (PC) se utilizo solucion ACD-A. Los PC fueron sometidos a gelificacion por la adicion de sales de calcio. Antes de la activacion de los PC se realizo conteo de plaquetas y leucocitos. La concentracion de los factores de crecimiento fue determinada mediante ELISA en los sobrenadantes de los PG y plasma. Se observo diferencias estadisticamente significativas (P < 0,01) entre los valores de plaquetas y leucocitos en sangre entera y los PC. No se encontraron diferencias estadisticamente significativas entre las concentraciones de TGF-β1 y PDGF-AB en los PC y plasma en funcion de la sal de calcio empleada para la activacion de los PC. La concentracion de TGF- β 1 estuvo altamente correlacionada con el numero de plaquetas presente en el PC. La metodologia descrita permite producir PG con potencial terapeutico en medicina regenerativa canina.