Objective To investigate the effects of caveolin-1 scaffolding domain peptide ( CSD-p)on expressions of extracellular matrix and Smads in human fetal lung fibroblasts. Methods Human fetal lung fibroblasts were cultured in vitro and divided into four groups. A control group: the cells were cultured in DMEMwithout TGF-β1 or CSD-p. A CSD-p treatment group: the cells were cultured in DMEMcontaining 5 μmol /L CSD-p. A TGF-β1 treatment group: the cells were cultured in DMEMcontaining 5 μg/L TGF-β1 .A TGF-β1 + CSD-p treatment group: the cells were cultured in DMEM containing 5 μg/L TGF-β1 and 5 μmol /L CSD-p. Caveolin -1 mRNA was detected by RT-PCR. Caveolin-1, collagen-Ⅰ, α-SMA, p-Smad2,p-Smad3 and Smad7 proteins were measured by Western blot. Results Compared with the control group,the Caveolin -1 mRNA and protein expressions in the cells of TGF-β1 group significantly reduced ( mRNA:0. 404 ±0. 027 vs. 1. 540 ±0. 262; protein: 0. 278 ±0. 054 vs. 1. 279 ±0. 085; P lt; 0. 01) , and the expression levels of collagen-Ⅰ and α-SMA proteins significantly increased ( collagen-Ⅰ: 1. 127 ±0. 078 vs.0. 234 ±0. 048; α-SMA: 1. 028 ±0. 058 vs. 0. 295 ±0. 024) . Meanwhile, the expression levels of p-Smad2 ( 1. 162 ±0. 049 vs. 0. 277 ±0. 014) and p-Smad3 proteins ( 1. 135 ±0. 057 vs. 0. 261 ±0. 046) increased with statistical significance ( P lt; 0. 01) , but the expression level of Smad7 protein significantly reduced( 0. 379 ±0. 004 vs. 1. 249 ±0. 046, P lt;0. 001) . In the CSD-p group, CSD-p had no significant effects on the expressions of above proteins compared with the control group. But in the TGF-β1 +CSD-p group, the overexpressions of collagen-Ⅰ, α-SMA, p-Smad2 and p-Smad3 induced by TGF-β1 were obviously inhibited by CSD-p ( collagen-Ⅰ: 0. 384 ±0. 040 vs. 1. 127 ±0. 078; α-SMA: 0. 471 ±0. 071 vs. 1. 127 ±0. 078;p-Smad2: 0. 618 ±0. 096 vs. 1. 162 ±0. 049; p-Smad3: 0. 461 ±0. 057 vs. 1. 135 ±0. 057; P lt; 0. 01) .Otherwise, the up-regulation of Smad7 ( 0.924 ±0. 065 vs. 0.379 ±0. 004) was found. Conclusions CSD-p can reduce fibroblast collagen-I and α-SMA protein expressions stimulated by TGF-β1 , possibly through regulation of TGF-β1 /Smads signaling pathway. It is suggested that an increase in caveolin -1 function through the use of CSD-p may be an intervention role in pulmonary fibrosis.
The kinematic model parameter deviation is the main factor affecting the positioning accuracy of neurosurgical robots. To obtain more realistic kinematic model parameters, this paper proposes an automatic parameters identification and accuracy evaluation method. First, an identification equation contains all robot kinematics parameter was established. Second, a multiple-pivot strategy was proposed to find the relationship between end-effector and tracking marker. Then, the relative distance error and the inverse kinematic coincidence error were designed to evaluate the identification accuracy. Finally, an automatic robot parameter identification and accuracy evaluation system were developed. We tested our method on both laboratory prototypes and real neurosurgical robots. The results show that this method can realize the neurosurgical robot kinematics model parameters identification and evaluation stably and quickly. Using the identified parameters to control the robot can reduce the robot relative distance error by 33.96% and the inverse kinematics consistency error by 67.30%.
In order to calibrate the hand-eye transformation of the surgical robot and laser range finder (LRF), a calibration algorithm based on a planar template was designed. A mathematical model of the planar template had been given and the approach to address the equations had been derived. Aiming at the problems of the measurement error in a practical system, we proposed a new algorithm for selecting coplanar data. This algorithm can effectively eliminate considerable measurement error data to improve the calibration accuracy. Furthermore, three orthogonal planes were used to improve the calibration accuracy, in which a nonlinear optimization for hand-eye calibration was used. With the purpose of verifying the calibration precision, we used the LRF to measure some fixed points in different directions and a cuboid’s surfaces. Experimental results indicated that the precision of a single planar template method was (1.37±0.24) mm, and that of the three orthogonal planes method was (0.37±0.05) mm. Moreover, the mean FRE of three-dimensional (3D) points was 0.24 mm and mean TRE was 0.26 mm. The maximum angle measurement error was 0.4 degree. Experimental results show that the method presented in this paper is effective with high accuracy and can meet the requirements of surgical robot precise location.