RESUMO

In this study, derived complex carcinoma (CC) and simple carcinoma (SC) cell lines were established and cultured under two-dimensional (2D) and three-dimensional (3D) conditions. The 3D was performed in six-well AlgiMatrix™ (LifeTechnologies®, Carlsbad, CA, USA) scaffolds, resulting in spheroids sized 50-125 µm for CC and 175-200 µm for SC. Cell viability was demonstrated up to 14 days for both models. Epidermal growth factor receptor (EGFR) was expressed in CC and SC in both systems. However, higher mRNA and protein levels were observed in SC 2D and 3D systems when compared with CC (P < 0.005). The connective tissue modulators, metalloproteinases-1, -2, -9 and -13 (MMPs), relaxin receptors 1 and 2 (RXR1 and RXR2) and E-cadherin (CDH1) were quantitated. All were upregulated similarly when canine mammary tumour (CMT)-derived cell lines were cultured under 3D AlgiMatrix, except CDH1 that was downregulated (P < 0.005). These results are promising towards the used of 3D system to increase a high throughput in vitro canine tumour model.

Assuntos

RESUMO

OBJECTIVES: To evaluate bone healing in an experimental radial ostectomy in dogs treated with autologous platelet-rich plasma (PRP), through histological, densitometric, radiographic studies, as well as expression of growth factors in the ostectomy gap. METHODS: Twenty-one dogs were randomly divided into either a control or a PRP group. All underwent unilateral ostectomy of the radius to generate a gap of 2.0 mm, that was stabilized with external skeletal fixation. The ostectomy gap was either filled with PRP or left empty as a control. The radiographic and densitometric studies were performed after surgery, then at intervals until 60 days during the post-surgery period. Histological and immunohistochemical evaluations were performed at seven or 60 days post-surgery. Analyses were performed using a statistical analysis system, and the level of significance was set at p <0.05. RESULTS: The median radiographic healing score in the PRP group increased significantly between day 0 and day 60. Furthermore, at 60 days, the median healing score and the proportion of healed ostectomies in the control group (score 1; 1/6 healed) and the PRP group (score 5; 4/5 healed) were significantly different. There were differences between groups in radiographic and densitometric values at days 45 and 60. The histological evaluation showed advanced bone healing at 60 days in the PRP group and signs of delayed union in the control group. CLINICAL RELEVANCE: Platelet-rich plasma can be used as an adjuvant therapy because it may promote better bone healing of a radial ostectomy treated with external skeletal fixation in dogs.

Assuntos

RESUMO

The present article aimed to assess bone healing of experimental radial fractures, treated or not with autologous PRP (platelet-rich plasma), by means of radiographic and densitometric studies. Eleven dogs were randomly allocated in two experimental groups: control group (CG n=6) and PRP group (PRPG n=5). All dogs underwent radial osteotomy and osteosynthese (external skeletal fixation) of the right forelimb, in which a 2.0 mm defect was created. The gap was filled with PRP in the treated group (PRPG); while CG received no treatment. Radiographic and densitometric studies were performed immediately at the end the procedure and 14, 21, 28, 35, 45 and 60 days after the surgery (M0, M14, M21, M28, M35, M45 e M60). Statistical analysis was performed using analysis of variance with repeated measures (ANOVA) followed by Tukey test to compare means Friedman and Dunn post hoc tests to compare times within each group; and Mann-Whitney to compare groups at all times (p<0.05). Regarding time, radiographic scores and densitometric values changed significantly from moment 0 to moment 60 within the PRPG. The comparison of the two groups shows that radiographic scores changed significantly from M28 and densitometric values from M45 and M60. It can be concluded that under the conditions of this study; PRP can be used as an adjutant therapy to promote bone healing of experimental radial fractures (gap 2.0 mm) of dogs treated with external skeletal fixation.

O presente artigo teve como objetivo avaliar a cicatrização óssea de fraturas experimentais do radio de cães, tratadas ou não com o PRP autógeno, por meio de estudos radiográfico e densitométrico. Foram utilizados 11 cães, alocados aleatoriamente em dois grupos experimentais: o grupo controle (G-controle, n=6) e o grupo PRP (G-PRP, n=5). Todos os animais foram submetidos à osteotomia e osteossíntese (fixador esquelético externo) do rádio direito, gerando-se um gap de 2mm, que foi preenchido com PRP apenas no grupo G-PRP. Os estudos radiográficos e densitométricos foram realizados no pós-operatório imediato e aos 14, 21, 28, 35, 45 e 60 dias de pós-operatório (M0, M14, M21, M28, M35, M45 e M60). A análise estatística foi realizada por meio da Análise de Variância com Medidas repetidas (ANOVA) e teste de Tukey para comparação de médias; teste de Friedman seguido do teste de Dunn para comparar os momentos em cada grupo e o teste de Mann-whitney para comparar os grupos em cada momento (p<0,05). Referente à avaliação entre os momentos houve diferença significativa entre MO e M60 nas avaliações radiográficas e densitométricas dentro do grupo G-PRP. Na comparação entre os dois grupos houve diferença estatística na avaliação radiográfica a partir de M28; e na avaliação densitométrica nos momentos M45 e M60. Conclui-se, nas condições deste estudo, que o PRP pode ser utilizado como terapia adjuvante, pois promove cicatrização óssea precoce em fraturas experimentais (gap de 2,0 mm) do radio de cães tratadas com fixador esquelético externo.

Assuntos