Objective To investigate current status in knowledge,attitude and practice(KAP)of transitional care among the nurses in Shaanxi province,identify the influencing factors that hinder the transitional care and carry out training of transitional care for the nurses in different specialties in order to provide a theoretical basis for establishing a transitional care model for discharged patients.Methods A total of 2 288 nurses were selected to participate the survey from 41 hospitals in Shaanxi province by the stratified two-stage random sampling method.A self-designed questionnaire for general information,an obstacle factor scale,and a KAP of transitional care questionnaire were used as the survey instruments.The data acquired from the survey were processed by Cluster analysis to identify potential categories and the influencing factors.Results Totally 2085 nurses finished the study.Total score of KAP of transitional care among the nurses in Shaanxi province was found at(134.96±23.75),which was at a medium level.The scores of knowledge,attitude and practice were 77.24%,80.64%and 76.98%respectively.Cluster analysis showed that all the nurses could be categorised into either a lower scored group(n=1 596,76.5%)or a higher scored group(489,23.5%),with a best potential category number of 2 for the 2 085 nurses who participated the survey.There were statistically significant differences between the groups in terms of care training,telephone follow-up,network platform,outpatient service of nursing experts,family visits,patient club and hospital categories(all P＜0.05).Logistic regression analysis on even factors above showed that care training,telephone follow-up,network platform and patient club could significantly affect the potential categorisation of KAP of the nurses in transitional care(all P＜0.05).The main factors that hindered the transitional care included insufficient human resources(93.81%),insufficient supply of community services(93.57%)and lack of a standardised flowchart for transitional care(93.09%).Conclusions Levels of KAP about the transitional care are at a medium level among the nurses of 41 hospitals in Shaanxi province,which indicates that the nurses are active in attitude,but the knowledge and practice are required to be further improved and standardised.The results of cluster analysis indicate that it is necessary for nursing managers to carry out targeted trainings in transitional care for the nurses in different categories.This study provides a theoretical basis to establish a diversified transitional care mode for discharged patients in Shaanxi province.

Objective To investigate corneal biomechanical differences in different geometric design parameters of orthokeratology lenses(OK lenses)and to further reveal the corneal shaping mechanism of OK lenses.Methods A coupled finite element model of the aspheric OK lens corneosclera was established for various geometric design parameters of the OK lens,corresponding to different degrees of myopia correction.The distribution trends of the profile and curvature of the corneal anterior surface,as well as the von Mises stress(VMS)and eye axis displacement on both the corneal anterior surface and superior corneal stroma surface were analyzed numerically.Results The stress concentration of the corneal anterior surface was observed in the mid-peripheral and peripheral zones,whereas that of the superior corneal stroma surface appeared in the mid-peripheral zones.The sagittal height of the base curve of the OK lens decreased with increasing degree of myopia correction.At myopia correction degrees of-2.0,-3.0,-4.0,-5.0,and-6.0 D,the maximum corneal VMS increased by 0.81%,1.86%,2.84%,3.81%,and 7.04%,respectively,compared with that at-1.0 D;the curvature of the corneal central zone was reduced by an average of 2.59,3.78,4.51,4.99,5.33,and 6.41 D compared with that without OK lenses.Conclusions The sagittal height of the base curve of the OK lens decreased with increasing degree of myopia correction,resulting in a flatter central curvature of the cornea.The base curve of the OK lens plays a crucial role in both correction and control of myopia.

Objective To investigate biomechanical differences of two posterior occipitocervical internal fixation techniques for treating basilar invagination with atlantoaxial dislocation (BI-AAD). Methods Intra-articular cage + posterior occipital plate+C2 pedicle screw (Cage+C2PS+OP), and intra-articular cage+C1 lateral mass screw+C2PS (Cage+C1LMS+C2PS) models were established based on occipitocervical CT data of the BI-AAD and clinical operation scheme, and the stability of atlantoaxial joint and stress distribution characteristics of C2 endplate and implanted instruments under different motion states were analyzed. Results Compared with the Cage+C1LMS+C2PS model, the atlantoaxial range of motion ( ROM) under flexion, extension, lateral bending and axial rotation in the Cage+C2PS+OP model were reduced by 5. 26% , 33. 33% , 43. 75% , -5. 56% , and stress peak of screw-rod fixation system were reduced by 47. 81% , 60. 90% , 48. 45% , 39. 14% , respectively. Under two internal fixation modes, stresses of C2 endplate and cage were mainly distributed on the compressive side during the motion, and both the screw-bone interface and the caudal side of screw subjected to large loading. Conclusions Two internal fixation methods could provide similar stability. However, the stress concentration of screw-rod system was more obvious and the possibility of screw loosening and fracture was greater under Cage+ C1LMS+C2PS fixation.

Objective To establish a mathematical model of tumor growth and invasion under radiotherapy, so as to numerically simulate the effect of radiotherapy on tumor growth and make sensitivity analysis.Methods The mathematical model of tumor growth and invasion with time evolution before and after radiotherapy was established. The model included four key variables in the process of tumor invasion: tumor cells, extracellular matrix (ECM), matrix-degradative enzymes (MDEs) and oxygen. The linear quadratic (LQ) model was used to simulate the survival probability of tumor cells after radiotherapy, and the effects of different radiotherapy schemes and radiotherapy coefficients on the treatment effect were discussed. Traditional radiotherapy and intraoperative targeted radiotherapy were compared.Results Under the premise of constant total dose, the results of radiotherapy were directly proportional to the radiotherapy coefficient, but not related to the radiotherapy frequency; the therapeutic effect of intraoperative targeted radiotherapy was better than that of standard treatment.Conclusions Simulation results are basically consistent with clinical experimental results. As a more efficient treatment method, intraoperative targeted radiotherapy can provide new ideas for clinical tumor treatment.

Objective To establish the finite element model of upper cervical vertebrae C0-3 with Jefferson fracture, and to analyze the influence of posterior atlantoaxial fusion (PSF) and occipitocervical fusion (OCF) on biomechanical properties of the vertebral body and mechanical conduction of the screw-rod system. Methods Based on CT images, the C0-3 segment Jefferson fracture model of human upper cervical spine was established. PSF, OCF1 and OCF2 internal fixation were performed according to surgical plan in clinic, and 50 N concentrated force and 1.5 N·m torque were applied to bottom of the occipital bone. The stress distribution and range of motion (ROM) of the cervical vertebral body, the maximum stress of the screw-rod system and the stress distribution of the intervertebral disc for C0-3 segment during flexion, extension, bending and rotation of the upper cervical spine were studied. Results Compared with PSF, the ROM of OCF1 and OCF2 vertebral bodies increased, and the stress of the nail rod decreased. OCF had a better fixation effect. Conclusions PSF, OCF1 and OCF2 fixation method can reduce the upper cervical ROM and restore stability of the upper cervical spine, which make stress distributions of the vertebral body and intervertebral disc tend to be at normal level. The research result can provide a theoretical basis for clinical surgery plan.

Objective To establish the three-dimensional (3D) finite element model of unicompartmental knee arthroplasty (UKA) with 3° and 7° posterior tibial slope at different knee flexion angles, and to study biomechanical properties and prosthetic wear of the knee joints with two types of posterior tibia slope and their effects on knee function. Methods Combining CT and MRI images of human knee joints with the 3rd-generation Oxford prosthesis, the finite element UKA model with 3° and 7° posterior tibia slope were established. The 1 kN load was applied to center point of the medial and lateral condyles of the femur to simulate the standing load of human body. The maximum stresses and distributions of the prosthesis and articular cartilage at different knee flexion angles were analyzed. ResultsThe maximum stress of the meniscus liner with 3° posterior tibia slope at 0°, 30°, 60°, 90°, 120° knee flexion angles increased by 28.06%, 68.99%, 19.45%, 21.06% and 53.38%, the distribution area was concentrated from the side of the meniscus liner to the central area, and the stress concentration was obvious at 120° knee flexion. The maximum stress of prosthesis with 3° posterior tibia slope was greater than that with 7 ° posterior tibia slope. The expansion of stress concentration area would cause wear and loosening of the prosthesis, contact stress and concentration area of the articular cartilage would subsequently increase with posterior tibia slope increasing, and stress concentration would be more obvious at high knee flexion angles. Conclusions Tibial prosthesis has the higher stress and greater wear under the condition of 3° posterior tibia slope than 7° posterior tibia slope. The research findings provide theoretical basis for the UKA design in clinic.

Department of Orthopedics, Yang Pu Hospital Affiliated to Tongji University,

Objective To investigate the influence of ROI-C cervical implantation in the C5-6 segment on the C3-7 range-of-motion (ROM), biomechanical properties of the intervertebral disc and the vertebral body, and the mode of force transmission. Methods Two types of surgeries, ROI-C implantation and autograft fusion with plate fixation, were considered to establish the finite element model of cervical C5-6 segment degeneration. The ROM of C3-7 during flexion, extension, lateral bending, and axial rotation, as well as stress distributions on the adjacent discs, vertebral body, and implanted devices under two procedures, were analyzed. Results ROI-C implantation had a relatively small influence on the ROM of the adjacent segment. The stress on the vertebral discs was reduced, but the stress on the vertebral body increased significantly, with the C5 vertebral body stress increasing by 251%. In the fusion surgery model, the ROM of the surgical segment was reduced by 86%-91%, while the ROM of the adjacent segments and the stress on the vertebral disc and vertebral body increased significantly. Conclusions ROI-C implantation surgery has a relatively small influence on the cervical ROM and the intervertebral disc, and it has a greater impact on the vertebral body. The research findings provide a theoretical basis for the design of operation plans and clinical studies on ROI-C implantation and autograft fusion with plate fixation.

Objective: To investigate the comprehensive nutritional status and diet behavior of middle aged and elderly women with osteoporosis, and thereby to explore the relationship between diet behavior and comprehensive nutritional status. Methods: 311 middle-aged and elderly women with osteoporosis in Chengdu were included in this study. Mini Nutritional Assessment (MNA) was applied to assess their comprehensive nutritional status. Information of social-demographic characteristics and diet behavior (about meals, snacks and water drinking, etc.) of the subjects was collected by questionnaire. Chi square test was used to assess the differences in nutritional status among patients who have different eating behaviors. Logistic regression analysis was performed to evaluate the relationship between diet behaviors and comprehensive nutritional status. Results: The mean MNA score of subjects was 25.8±2.5. 20.3% (63/311) of the subjets were at risk of potential malnutrition, but there was no malnourished subjects found. 46.9% (46/311) of the subjects were in good appetite. 95.2% (296/311) of them had a fixed food intake each meal. 65.8% (198/311) of them had snacks every day, and the most common choice was fruit (86.4% (248/287)). 54.8% (165/311) of them had initiative drinking water habits, and the most common choice was plain boiled water (79.9%, 246/308). 76.5% (238/311) of them had daily portable water less than 1 500 ml. After adjusting the effects of age, occupation and education level, bad appetite (OR=3.50, 95%CI: 1.18-10.62), unfixed food intake (OR=7.27, 95%CI: 1.40-35.83), and seldom or never intake of snack (OR=3.71, 95%CI: 1.42-9.72) were risk factors for malnutrition risk, while tea drinking was protective factor(OR=0.31, 95%CI: 0.11-0.93). Conclusion Risk of potential malnutrition and unhealthy diet behavior among the middle aged and elderly women with osteoporosis should be paid more attention. Unhealtghy diet behavior has a negative effect on their comprehensive nutritional status.

Objective_To study the effect of human insulin on cell cycle progression and apoptosis of rat liver cell line BRL-3A in vitro.Methods_MTT method was used to observe the effect of insulin on cell activity, and flow cytometry was used to detect cell apoptosis and cell cycle.qRT-PCR was used to evaluate the expression of related genes.Results_Human insulin induced the proliferation of BRL-3A cells in a dose-dependent manner ( P<0.05 or P<0.01);After 3 days treated by human insulin (500 nmol/L), the proportion of cells in G0/G1 phases re-markably decreased (P<0.05).Moreover, pro-apoptotic BAX was down-regulated (P<0.05), while cell prolif-eration-related gene CCNA2 was up-regulated (P<0.05).Conclusions_Human insulin may inhibit the apoptosis of BRL-3 A cell line and induce proliferation due to the down-regulated expression of BAX and up-regulated expres-sion of CCNA2 .