H.P. Oliveira

Comparison of the osteogenic potential of mesenchymal stem cells from the bone marrow and adipose tissue of young dogs

BackgroundThe aim of the present study was to compare the osteogenic potential of mesenchymal stem cells extracted from the bone marrow (BM-MSCs) and adipose tissue (AD-MSCs) of young dogs. The following parameters were assessed: dimethyl thiazolyl diphenyl tetrazolium (MTT) conversion, alkaline phosphatase (ALP) activity, collagen and mineralised matrix synthesis, and the expressions of osterix, bone sialoprotein (BSP), and osteocalcin (OC).ResultsMTT conversion was greater in BM-MSCs compared to AD-MSCs after 14 and 21 days of differentiation; ALP activity was greater in differentiated AD-MSCs on day 7; collagen synthesis was greater in BM-MSCs on days 14 and 21; the percentage of mineralized area per field was greater in BM-MSCs compared to AD-MSCs; osterix expression was greater in BM-MSCs in days 14 and 21, and BSP and OC expression levels were greater in BM-MSCs at all the investigation time-points.ConclusionsIt was concluded that the osteogenic potential was greater in BM-MSCs than AD-MSCs when extracted from young dogs.

Emprego experimental da placa de compósito poli-hidroxibutirado/hidroxiapatita na fixação femoral em gatos

The composite of polyhydroxybutyrate (PHB) 70% and hydroxyapatite (HA) 30% was evaluated as plate for bone fixation in cats. The employed composite plates presented six orifices and measured 60 x 10mm, length and width, respectively, with thickness ranging from 3 to 5mm according to the region. The composite plate was used in the fixation of femoral osteotomy in four cats, in a total of six interventions. There were ruptures in five plates (83.3%) until day 4 and in one plate (16.7%) on the day 21, when it was possible to observe an exuberant osseous callus. The result of the plate deployment in the cat showed that the composite does not have sufficient strength to be used as plate of femoral fixation in cats.

Cortisol sérico e glicemia em cadelas tratadas com tramadol e submetidas à ovário-histerectomia

Tramadol is an opiate analgesic used in veterinary medicine, although few studies exist on this drug. The objective of this work was to evaluate the analgesic effect promoted by the administration of tramadol, determined the serum cortisol and blood glucose concentrations of female dogs. For that, 15 animals were used, submitted to the ovaryhysterectomy under general anesthesia with isofluorane. The animals were assigned into three groups. Group 1 (Tep): received epidural tramadol (1.0mg kg-1 diluted in bi-distilled water at 3.0mL final volume), followed by 3.0mL of bi-distilled water applied intravenously fifteen minutes later. Group 2: (Tiv) 3.0mL of bi-distilled water applied via epidural, following intravenous tramadol (1.0mg kg-1 diluted in bi-distilled water at 3.0mL final volume) applied fifteen minutes later. Group 3 (CT): 3.0mL of bi-distilled water applied via epidural, followed by 3.0mL of bi-distilled water applied intravenously fifteen minutes later. The efficacy of each analgesia regimen was evaluated for 12 hours after epidural. There were no significant differences among the experimental groups to the studied variables (P(0.05). Significant differences were observed in each treatment. In the Tep group, there was a serum cortisol increase in the 25 minutes of the transoperatory (M3), in relation to the obtained value right after the anesthesia induction (M2) (P<0.05). In the Tiv and CT groups, we could check an elevation of the variables two (M4) and four (M5) hours of the epidural injection, when compared to the pretreatment (M1) (P<0.05). In these periods, the variables that were studied in the Tep treatment were statistically similar to the pretreatment (M1). According to the results it can be concluded that 1) used methods were sensitive to determine the most stressful surgical moments as well as and, 2) epidural tramadol seems to produce longer analgesia when compared to the intravenous administration.

Avaliação mecânica da placa de compósito de poli-hidroxibutirato e hidroxiapatita em modelos ósseos de gato

Fixation bone plates made of 70% polyhydroxybutyrate and 30% hydroxyapatite composite were mechanically evaluated. The fifteen composite plates employed presented six holes and measured 60 x 10mm, length and width, respectively, with thickness ranging from 3 to 5mm according to the region. The plates were fixed in acrylic models of cat femur, then were subjected to tests of four-points bending, axial compression, and torsion, using as reference 2mm stainless steel plates. The means of the maximum force in flexion and compression tests were, respectively, 323.20N and 617,70N for the composite plates and 352.33N and 547.70N for the steel plates. In the torsional test, the means of torque were 1.01Nm for the composite plates and 1.15Nm for steel plates. There were no statistical differences between the plates of composite and steel. The physical behavior of the material was different once the composite plates broke up while the stainless steel ones only presented deformation, revealing the low ductility of the composite plates

Efeitos da solução salina hipertônica a 7,5% em glicose a 5% nas concentrações séricas de sódio, cloreto e potássio de eqüinos com hipovolemia induzida

The effect of isotonic and hypertonic solutions on serum levels of sodium, chloride and potassium and cardiac (CR) and respiratory rates (RR) of hypovolemic horses were studied. Fifteen horses weighting from 390 to 475kg, aging from four to 18-years-old were submitted to bleeding of 2% of body weight and divided in three groups: 7.5% NaCl hypertonic saline in 5% glucose (GSH), 0.9% NaCl isotonic saline and control group (GC). Serum electrolytes were evaluated before (T0) and after bleeding (T1) and after the administration of the solutions between 20 and 30 minutes (T2), 60 and 70 minutes (T3) and 120 and 130 minutes (T4). After T0, CR and RR increased while serum sodium, chloride, potassium were not affected. After the treatment, the clinical variables improved in GSI and GSH as compared to GC. The Na levels increased in GSH at T2 being higher than T3 and T4 while chloride and potassium concentrations did not change. The hypertonic and isotonic solutions safely corrected the hypovolemia of the horses, without altering significantly the electrolyte balance.

Efeito do produto iônico do biovidro 60S na diferenciação osteogênica de células-tronco mesenquimais do tecido adiposo de cães

The aim was to evaluate the ionic product of 60S bioglass (BV60S) in osteogenic differentiation of mesenchymal stem cells from adipose tissue (ADMSCs) in dogs. ADMSCs were differentiated without the ionic product (OST) and with the ionic product (PI-OST) for 7, 14 and 21 days. We evaluated the MTT, alkaline phosphatase (ALP), collagen mineralization and expressions of osterix (OSX), bone sialoprotein (BSP), osteonectin (ON) and osteocalcin (OC). The PI-OST group had a lower MTT conversion to 7days and higher conversion at 21 days. The ALP activity was higher in the OST group at 14 and 21 days. Collagen synthesis was higher in the OST group at 7 and 21 days. A higher mineralized area in the PI-OST group was observed at all times. There were no differences in expressions of OSX and OC between groups. We observed increased expression of BSP in the PI-OST group at 14 and 21 days. The expression of ON was higher in the OST group at 14 days. It was concluded that the ionic product of BV60S promotes in vitro osteogenesis of MSC-AD from dogs.

Aspectos clínicos e radiográficos do pericárdio bovino como substituto do ligamento cruzado cranial de cães

Avaliaram-se os aspectos clinicos e radiograficos do enxerto de pericardio bovino, preservado em glicerina, como substituto do ligamento cruzado cranial. Quinze caes machos, sem raca definida, pesando entre 17,4 e 31,6 kg, foram submetidos a ruptura experimental do ligamento cruzado cranial e a substituicao por pericardio, via videoartroscopia. Os caes foram divididos em tres grupos de cinco e avaliados aos 30, 90 e 120 dias. O membro operado foi imobilizado por duas semanas e procederam-se avaliacoes clinicas semanais. Radiografias foram feitas mensalmente e foram realizadas colheita de liquido sinovial nos tempos descritos. Clinicamente, os caes mostraram claudicacao acentuada a moderada, hipotrofia muscular no membro operado e acentuado deslocamento cranial da tibia em relacao ao femur. As alteracoes degenerativas foram observadas nas radiografias. Observou-se instabilidade acentuada em todos os animais. O liquido sinovial tinha caracteristicas de inflamacao. Concluiu-se que o enxerto rompeu precocemente, provocou reacao inflamatoria persistente e fenomenos de rejeicao, nao sendo, portanto, recomendado para substituicao do ligamento cruzado cranial de caes.

Fraturas odontomaxilares e mandibulares em eqüídeos tratados por diferentes técnicas de osteossíntese

Eight equines and one mule with odontomaxillaries and mandibularies fractures were treated with different osteosynthesis modified techniques, consisting of cerclages with or without tension bands, neutralization plates, and intraosseous pin applied by a methodology which was not found in the literature. The surgery procedures in equides were performed with the animals in stand position under physical contention, sedation, or neuroleptoanalgesy and regional nerve block. All animals were able to eat voluntarily in the immediate post-operatory time and had good bone recuperation.

Uso de dilatador temporário em papilas mamárias de vacas, submetidas a lesões experimentais

Thirty two mammary teats of Holstein cows, in the dry period, were submitted to histological examination. Lateral thelostomy was performed in all teats, producing a linear defect on the mucous membrane of the lactiferous sinus (MMLS). The teats were also submitted to a standard rectangular excision on the mucous membrane of MMLS, on the opposite side of thelostomy. All thelostomies were sutured and then the teats were divided in 2 groups. One group received Foleyss catheter of 2.7mm in diameter and was designed teat distention group. The 16 remain teats formed the no teat distention group. The Foleyss catheter balloon distention produced MMLS dilatation and also a 7 days maintenance period on the mammary teat. The scar evaluation of the linear and rectangular defects, performed trough morphologic and histological examinations showed that the dilatation on MMLS contributes on the scar orientation, keeping the lactiferous sinus patency in a greater number of teats, when both groups were compared. The MMLS dilatation interferes with telothomies healing, can observe so more alterations on the mucous membrane of lactiferous sinus.

Estudo comparativo da diferenciação osteogênica das células tronco mesenquimais da medula óssea e do tecido adiposo de cães adultos

O objetivo deste estudo foi comparar o potencial osteogenico das celulas tronco mesenquimais extraidas da medula ossea (CTM-MO) com as do tecido adiposo (CTM-AD) de caes adultos. As celulas foram caracterizadas fenotipicamente quanto a expressao de CD29, CD90, CD34 e CD45 e submetidas a diferenciacao adipogenica e condrogenica por 21 dias e osteogenica por 7, 14 e 21 dias. Foram constituidos quatro grupos: 1) CTM-MO em meio osteogenico, 2) CTM-MO em meio basal, 3) CTM-AD em meio osteogenico e 4) CTM-AD em meio basal. Aos 7, 14 e 21 dias de diferenciacao osteogenica as culturas foram submetidas as avaliacoes da conversao de MTT em formazan, da atividade da fosfatase alcalina (FA), da sintese de colageno e de matriz mineralizada, avaliacao do numero de celulas por campo e foram quantificados os transcritos genicos para osterix, sialoproteina ossea (BSP), osteonectina (ON) e osteocalcina (OC). Tanto as celulas extraidas da medula ossea quanto do tecido adiposo mostraram elevada expressao de marcadores para celulas tronco e baixa expressao de marcadores de celulas hematopoieticas (menor que 2%). Alem disso, foram capazes de se diferenciar em osteoblastos, condrocitos e adipocitos. As CTM-AD submetidas a diferenciacao osteogenica mostraram maior conversao do MTT em formazan que as CTM-MO, sob mesmas condicoes aos 7 e 21 dias. O numero de celulas por campo, a atividade da FA, a sintese de colageno e de matriz mineralizada foram superior nas CTM-AD em diferenciacao, em relacao as CTM-MO sob as mesmas condicoes, em todos os tempos estudados. As expressoes de osterix, BSP e OC foram predominantemente superiores nas CTM-MO diferenciadas, mas a expressao de ON foi superior nas CTM-AD diferenciadas aos 7, 14 e 21 dias. Conclui-se que as CTM-AD apresentam maior potencial osteogenico que as CTM-MO quando extraidas de caes adultos.