This paper is to report our study in which the differences between prosthetic restoration and surgical reconstruction using traditional clasp retention technology were analyzed based on three-dimensional finite element methods in our laboratory. Firstly, the maxillary unilateral defect model was developed using medical image processing software MIMICS. Secondly, the prosthesis was generated by mirroring technology. The clasp was designed according to the methods raised by Aramany. Then, the stress distribution of maxilla was calculated by simulating occlusion. According to the results, after osseointegration of surgical reconstruction, stresses of unaffected abutments were reduced significantly, and less stress of junction occurred near zygoma of affected side, which were all less than stresses of prosthesis restoration. Thus, removing the clasp of surgical reconstruction increased the stresses of unaffected abutments. The stress trends of maxillary components were different between prosthetic restoration and surgical reconstruction. Surgical reconstruction is better than prosthesis restoration in protection of the abutments. Clasp can alleviate the occlusal burden of maxilla. Varieties of retentive technologies can be considered in prosthesis restoration. The surgical reconstruction is more conducive to rehabilitate unilateral maxilla biomechanically in clinic.
Biomechanical Phenomena ; Finite Element Analysis ; Humans ; Image Processing, Computer-Assisted ; Mandibular Reconstruction ; methods ; Maxilla ; surgery ; Maxillofacial Prosthesis ; Osseointegration ; Zygoma

Objective To evaluatate the impact of different anastomotic location and preventive ileostomy on postoperative anastomotic fistula in rectal cancer patients.Methods The clinical data of 316 cases of rectal cancer patients after total mesorectal excision from January 2015 to January 2016 were analyzed retrospectively.Patients were divided into anterior resection (AR) group,low anterior resection (LAR) group,uhra-low anterior resection (ULAR) group according to the anastomotic location.There were 33 cases of anastomotic fistula with preventive ileostomy or without and anastomotic leakage varied from mild to severe as grade A,B,C.Results There was no statistically significant difference in the incidence of anastomotic fistula between the different anastomotic location (x2 =3.829,P =0.147).In anterior resection group and low anterior resection group,there was no statistically significant difference in the incidence of anastomotic fistula whether or not a preventive ileostomy was performed (x2 =0.606,1.096,P =0.436,0.326).While in uhralow anterior resection group,preventive ileostomy helped dicrease the incidence of anastomotic fistula (x2 =11.667,P =0.001),and once happened the severity of the anastomotic fistula tended to be less severe.Conclusion The incidence of anastomotic fistula does not vary with anastomotic level in our study.Preventive ileostomy reduces the incidence of anastomotic fistula in patients with ultralow anterior resection.

Observation revealed the abnormalities (increased CD 4 and Th, decreased Tc) in patients of Graves′ disease, and these abnormalities were not significantly adjusted after 6 weeks of treatment with methimazole (MMI), or with MMI and methotrexate (MTX), though the soluble interleukin-2 receptor and thyroid autoantibodies slightly decreased in both groups. However, the addition of MTX did not show any better effects than MMI alone in the treatment.

Objective To compare the efficacy and safety between mono-chemotherapy and targeted therapy as first-line regimen for patients over 80 years old with advanced non-small cell lung cancer (NSCLC).Methods 108 NSCLC patients aged ≥80 years in our hospital were divided into two groups according to the therapeutic program,of which group A was mono-chemotherapy group (n =60) and group B was targeted therapy group (n =48).The primary endpoint was overall survival (OS) and progression free survival (PFS),while secondary endpoint was objective response rate (RR),disease control rate (DCR) and safety.Results The median PFS,and median OS in group B were significantly longer than those in group A (P =0.013,0.025).The 1-year survival rate of group B was significantly higher than that of group A (P =0.001),and there was no significant difference between the two groups (P =0.605).There was also no statistically significant difference in RR between the two groups (P =O.408).DCR in Group B was significantly higher than that in group A (P =0.043).The incidence of skin rash in group B was significantly higher than that in group A,and the incidence of adverse reactions and hematological toxicity in group A was significantly higher than that in group B.Conclusions Compared with single-agent chemotherapy,epithelial growth factor receptor-tyrosinekinase (EGFR-TKI) targeted therapy has longer PFS and OS benefits for patients ≥ 80 years with advanced NSCLC,and was well tolerated by patients.

Objective To assess the effects of early correction of anemia with recombinant human erythropoietin (rHuEPO) on the development and progression of left ventricular hypertrophy (LVH) in patients with mild-to-moderate chronic renal insufficiency (CRI) who are not on hemodialysis. Methods A total of 158 patients with serum creatinine from 147μmol/L to 400μmol/L were nrolled in this prospective, multicenter study. Eighty-six patients with hemoglobin (Hb)＜110g/L received rHuEPO treatment with a target Hb of ≥110g/L (Group A). Forty patients with comparable Hb concentration (＜110g/L) but did not receive rHuEPO (Group B) and 32 patients with Hb≥110g/L and without rHuEPO treatment (Group C) were served as controls. Left ventricular mass index (LVMI) was evaluated by echocardiography at baseline and every 3 months for 2 years. Results There was no difference in age, gender, etiology of renal failure, blood pressure and cardiovascular risk factors among the 3 groups. At baseline, the prevalence of LVH was 72.1% in group A,72.5% in group B and 59.4% in group C. LVMI was inversely correlated with Hb levels (r=0.70, P＜0.01). During the 2-year period, the mean LVMI decreased from 142.6±25.7g/m2 to 132.4±18.5 g/m2 in group A, while increased significantly in both group B and group C. The mean Hb concentration increased from 93.8±14.6g/L to 111.2±10.3g/L (P＜0.05) in group A, but tended to decrease in group B and group C. There was no significant change of the mean blood pressure, number of anti-hypertensive drugs and serum creatinine concentrations in all 3 groups. However, patients' serum creatinine doubled more often in group B and group C than in group A.Conclusions LVH was common in predialysis CRI patients and was associated with the severity of anemia. Early intervention with rHuEPO may reverse LVH in these patients.

Objective: To analyze the epidemiological and etiological characteristics of aggregation epidemics of infectious diarrhea induced by norovirus, and to provide the scientific basis for the prevention and control. Methods: A descriptive epidemiological analysis of aggregation epidemics events occurred during 2016-2018 in Longhua District of Shenzhen was carried out, with subtypes identified by real-time fluorescence quantitative PCR, Region B and Region C fragment sequence determination. Results: There were 34 aggregation epidemic events,including 448 cases, the mean attack rate was 18.26%(448/2 454). The median duration of aggregation epidemic was 3 days. The peak season appeared in autumn and winter, and the peak of epidemic emerged from December 2016 to April 2017. About 91.18% (31/34) of the epidemics occurred in schools and child care centers, and among children aged 3-6 years (78.79%, 353/448). The clinical symptoms were mainly nausea and vomiting (95.77%, 408/426) in children and adolescents but diarrhea in adult group (95.45%, 21/22). The differences between vomiting and diarrhea were both statistically significant in the two age groups (χ2=98.89，99.61，P<0.01). 29 cases were transmitted through interpersonal network, of which 21 cases were found to have unregulated treatment of vomit on campus. The detection rate of biological samples was 49.15% (203/413), all of which were G Ⅱ norovirus. The genotype was mainly GⅡ.P16-G Ⅱ.2(n=49)from November 2016 to April 2017. Conclusion Norovirus can cause large-scale outbreaks in child care centers and schools easily. Early standardized patient isolation and proper management of vomit and diarrhea are the key steps in prevention and control measures.

Objective:To calculate the relative biological effectiveness (RBE) value of the released low-energy electrons in gadolinium neutron capture therapy ( 157GdNCT) based on microdosimetry. Methods:The Monte Carlo (MC) code Geant4-DNA package was used to simulate the energy deposition distribution and microdosimetry parameters of low-energy electrons released during gadolinium neutron capture treatment in different sensitive target volumes and physical models on track structures. On this basis, RBE value was obtained based on the microdosimetry kinetic model (MKM).Results:The low-energy electron RBE value was highly variable in different sensitive target volumes and decreases with increasing sensitive target volumes. With 6-nm-diameter sensitive target as reference, RBE value was 1.77 for 6-nm diameter, 1.53 for 10 nm diameter with percentage difference 13%, and 1.40 for 15-nm diameter with percentage difference of 21%, respectively. The effect of different Geant4-DNA physical models on the RBE of low-energy electrons was small. Using the RBE value of 1.53 for physical model option2 as reference, the RBE values of option6 and option7 were 1.49 and 1.52, respectively, with the percentage differences of 2.6% and 0.6%, respectively.Conclusions:The RBE values of low energy electrons released by 157GdNCT in different sensitive target volumes and physical models were calculated by MKM to be 1.40-1.77.

Objective To improve the clinical application of using rehabilitation robot for hand rehabilitation and solve the current shortcomings of rigid hand rehabilitation robot, such as complex structure, heavy weight, potential safety hazard, a new soft and wearable robotic glove was proposed. Methods The robotic glove was driven by McKibben pneumatic artificial muscles (PAMs). The tendon drive system was designed based on simulation of human hand anatomy and physiology structure, which could transmit forces and torques through the user’s own skeleton and joints. The normal hand movement could be simulated and this design pattern highly reduced the weight of the robotic glove. Meanwhile a surface electromyogrphy (sEMG) collecting circuit was developed to acquire sEMG signals from the forearm. User intent could be detected by measuring the sEMG of flexor digitorum superficialis and extensor digitorum communis on the forearm. Results The results of the experiment investigation on characteristics of the soft robotic glove showed that the robotic glove could effectively assist people completing daily activities and grasping daily necessities. The feasibility and scientificity of the robotic glove was validated. Conclusions The soft and wearable robotic glove has an advantage of light weight, easy operation and high comfortableness, and it can provide references for the study and design of similar hand rehabilitation devices.

Objective To investigate the structure and mechanical properties of pods after dehydration and the biomechanical mechanism of spreading pod seed injection due to torsion crack. Methods The layered pods, the cell size and direction at different cellular layers were analyzed by histology, microstructure observation, mechanical property test and high-speed photography. The process of pod ejection was observed, and the principle of pod ejection was summarized. Results The ejection of pods started from the crack of the bottom, and cracked gradually from the bottom to the top. The cell arrangement of two parts of the same pod was opposite. Each pod was divided into 4 layers wherein the first exterior layer and the middle layer were orthogonal to each other. There was a layer of cells between the first exterior layer and the middle layer, of which the cell wall was broken. In the process of dehydration, fibers in the outer layer shrank and fibers in the middle layer stretched. Conclusions Pod fiber will be contracted in the orthogonal direction after dehydration to accumulate elastic performance and generate pre-stress, and finally the pod is cracked to release the pre-stress.

OBJECTIVE：To compare the content changes of active/toxic ingredient genkwanin in ethanol extract from Wikstroemia indica before and after processing with “sweat soaking method ”and the effects of processing method on its anti-oxidation ability. METHODS ：HPLC method was adopted to determine the content of genkwanin in W. indica before and after processing with “sweat soaking method ”. The separation was performed on Diamonsil C 18 column with 0.2％ phosphoric acid solution-methanol as mobile phase （gradient elution ）at the flow rate of 1 mL/min. The column temperature was 30 ℃ and detection wavelength was set at 346 nm. The sample size was 20 µL. SD rats were randomly divided into blank group ，W. indica raw product ethanol extract group （317.52 mg/kg，called“raw-product group ”as short ）and W. indica processed product ethanol extract group （317.52 mg/kg，called“processed-product group ”as short ），with 6 rats in each group. Blank group was given constant volume of 1.0％CMC-Na solution intragastrically ，and administration groups were given relevant medicine suspension intragastrically；all of them were given 20 mL/kg，once a day ，for consecutive 14 days. The contents of serum oxidant stress indexes（MDA，CAT，SOD）in rats were determined by ELISA. RESULTS ：The linear range of genkwanin were 0.147-27.360 μg （r＝0.999 9）；RSDs of precision ，reproducibility and stability tests were all lower than 3％ ；average recoveries were 98.64％-98.92％（RSD＜1％，n＝3）. Before and after processing with “sweat soaking method ”，average contents of genkwanin in W. indica were 0.377 6 and 0.234 0 mg/g. Compared with blank group ，the serum content of SOD in raw-product group was increased significantly ，while CAT content was decreased significantly （P＜0.05 or P＜0.01）；the serum content of MDA was decreased significantly in processed-product group ，while SOD content was increased significantly （P＜0.05 or P＜0.01）. MDA content of processed-product group was significantly lower than that of raw-product group ，while SOD content was significantly higher than raw-product group （P＜0.05）. CONCLUSIONS ：After proce ssing with “sweat soaking method ”，the content of genkwanin in W. indica is decreased ，and antioxidant activity is increased .“Sweat soaking method ”processes certain function of “reducing toxicity and increasing efficiency ”.