Can pirfenidone prevent tendon adhesions? An experimental study in rats.

OBJECTIVES: In this experimental study, we aimed to investigate the effectiveness of oral pirfenidone (PFD) treatment on preventing tendon adhesion and tendon healing in rats. MATERIALS AND METHODS: A total of 21 rats were assigned into three groups including seven rats in each group. In Group 1 (sham group), no surgical procedure was performed. In Group 2 (control group), tendon repair was performed following right achillotomy. In Group 3 (treatment group), the rats also underwent tendon repair after right achillotomy. Additionally, 30 mg/kg of oral PFD was initiated from the postoperative Day 1 and administered via gavage for 28 days. At the end of the study, tendon healing and fibrosis levels in the tendon repair site were compared macroscopically, histopathologically, and immunohistochemically among the groups. RESULTS: Macroscopically, moderate and severe adhesions were observed in four and three rats, respectively in the control group, while no adhesion was found in four rats and filmy adhesions were observed in three rats in the treatment group (p<0.01). Microscopically, there was moderate adhesions in three rats and severe adhesions in four rats in the control group, while three rats had no adhesions and four rats had slight adhesions in the treatment group (p<0.01). Microscopically, tendon healing was good in six rats and fair in one rat in the control group, while five rats showed excellent tendon healing and two rats showed good tendon healing in the treatment group (p<0.01). Immunohistochemically, expressions of collagen I (p<0.01), collagen III (p<0.001), vascular endothelial growth factor (VEGF) (p<0.001), and proliferating cell nuclear antigen (PCNA) (p<0.001) significantly decreased in the treatment group compared to the control group. CONCLUSION: Our study results indicated that PFD decreased collagen synthesis and prevented the formation of peritendinous adhesion in rats; however, it did not impair tendon healing.

The prediction of live weight of hair goats through penalized regression methods: LASSO and adaptive LASSO.

The least absolute selection and shrinkage operator (LASSO) and adaptive LASSO methods have become a popular model in the last decade, especially for data with a multicollinearity problem. This study was conducted to estimate the live weight (LW) of Hair goats from biometric measurements and to select variables in order to reduce the model complexity by using penalized regression methods: LASSO and adaptive LASSO for γ = 0.5 and γ = 1 . The data were obtained from 132 adult goats in Honaz district of Denizli province. Age, gender, forehead width, ear length, head length, chest width, rump height, withers height, back height, chest depth, chest girth, and body length were used as explanatory variables. The adjusted coefficient of determination ( R adj 2 ), root mean square error (RMSE), Akaike's information criterion (AIC), Schwarz Bayesian criterion (SBC), and average square error (ASE) were used in order to compare the effectiveness of the methods. It was concluded that adaptive LASSO ( γ = 1 ) estimated the LW with the highest accuracy for both male ( R adj 2 = 0.9048 ; RMSE  =  3.6250; AIC  =  79.2974; SBC  =  65.2633; ASE  =  7.8843) and female ( R adj 2 = 0.7668 ; RMSE  =  4.4069; AIC  =  392.5405; SBC  =  308.9888; ASE  =  18.2193) Hair goats when all the criteria were considered.