In the study of oral orthodontics, the dental tissue models play an important role in finite element analysis results. Currently, the commonly used alveolar bone models mainly have two kinds: the uniform and the non-uniform models. The material of the uniform model was defined with the whole alveolar bone, and each mesh element has a uniform mechanical property. While the material of the elements in non-uniform model was differently determined by the Hounsfield unit (HU) value of computed tomography (CT) images where the element was located. To investigate the effects of different alveolar bone models on the biomechanical responses of periodontal ligament (PDL), a clinical patient was chosen as the research object, his mandibular canine, PDL and two kinds of alveolar bone models were constructed, and intrusive force of 1 N and moment of 2 Nmm were exerted on the canine along its root direction, respectively, which were used to analyze the hydrostatic stress and the maximal logarithmic principal strain of PDL under different loads. Research results indicated that the mechanical responses of PDL had been affected by alveolar bone models, no matter the canine translation or rotation. Compared to the uniform model, if the alveolar bone was defined as the non-uniform model, the maximal stress and strain of PDL were decreased by 13.13% and 35.57%, respectively, when the canine translation along its root direction; while the maximal stress and strain of PDL were decreased by 19.55% and 35.64%, respectively, when the canine rotation along its root direction. The uniform alveolar bone model will induce orthodontists to choose a smaller orthodontic force. The non-uniform alveolar bone model can better reflect the differences of bone characteristics in the real alveolar bone, and more conducive to obtain accurate analysis results.
Biomechanical Phenomena ; Computer Simulation ; Finite Element Analysis ; Humans ; Models, Biological ; Periodontal Ligament ; Stress, Mechanical ; Tooth Movement Techniques

Objective To study the effects of different root control attachment on root control and periodontal ligament （PDL） stress during canine distal translation in plastic aligner-based orthodontic treatment. Methods Through three-dimensional (3D) finite element technology, 11 models composed of 4 attachments and 3 kinds of loading were established. Namely, attachment A: no attachments; attachment B: traditional vertical rectangular attachment; attachment C: 1/4 spherical double optimized attachment; attachment D: double optimized door arch attachment; load a: 0.15 mm distal translation of the canine; b: load a+ application of 30 N·mm counterclockwise torque to stress surface of the attachment; load c: load a+ application of 30 N·mm counterclockwise torque to the entire crown. The root control effect of distal translation of the right maxillary canine was simulated with plastic aligner under different loads. Results Displacement modes of all models were distally tipped translation. The double optimized door arch attachment showed the optimal root control effect during canine distal translation. The root control effect for two groups of double optimized attachment was better than that of traditional rectangular attachment. The effect of adding attachments on root control of the canine was better than that of applying only counterclockwise couple. The PDL stress mainly appeared in distal alveolar ridge and root apex without attachment, while the PDL stress mainly appeared in distal alveolar ridge with attachment. Conclusions The most suitable measure to improve the effect of root control during canine distal translation is to use the double optimized door arch attachment in clinic.

Objective:To evaluate the efficacy of orthogonal low profile double-plate osteosynthesis (DPO) in the treatment of Neer type IIB distal clavicular fractures.Methods:A retrospective case-control study was carried out to analyze the clinical data of 31 patients with Neer type IIB distal clavicular fractures admitted to Second Affiliated Hospital of Zhejiang University School of Medicine from June 2016 to October 2017. There were 23 males and 8 females, aged 45-76 years(mean, 61.8 years). The left side was involved in 24 patients and right sidein 7. Out Of them, 7 patients were treated with hook plate osteosynthesis (HPO) (HPO group), 13 patients with precontoured distal clavicular locking plate osteosynthesis (LPO) (LPO group), and 11 patients with DPO (DPO group). The Constant-Murley shoulder functional outcomes, clavicle-coracoids distance (CCD), complications and hardware related symptomswere compared between groups.Results:All the patients were followed up for 10-27months(mean, 15.1 months). At the latest follow-up, Constant-Murley score was (93.8±5.1)points in LPO group and (94.8±5.8)points in DPO group, better than (84.3±13.2)points in HPO group ( P<0.05), while there was no significant difference between DPO and LPO groups ( P>0.05). CCD was increased(1 patient in HPO group, 5 in LPO group, 3 in DPO group), but there was no significantdifference between groups( P>0.05). No infection or implant breakage occurred in each group. One patient had nonunion in HPO group, 1 had malunion at trapezoid ligament bony end in LPO group and all had bone union in DPO group, showing no significant difference between groups ( P>0.05). Two patients had acromial bone corrosion and 1 had distal clavicle osteolysisin in HPO group, but not in LPO and DPO groups ( P<0.05). Three patients had hardware related symptoms in HPO group, 6 in LPO group, and none in DPO group ( P<0.05). Conclusion:Orthogonal low profile DPO can be a good choice for the treatment of distal clavicle Neer type IIB fractures, for it has advantages of good functional outcomes, lower complications and less hardware related symptoms.

Objective To investigate the effect of Shanzha Xiaozhi Capsules (SXC) on body weight, metabolic indexes, body fat accumulation and distribution of obesity patients with phlegm-dampness constitution. Methods Fifty obesity patients with phlegm-dampness constitution were randomized into control group and medicine group, 25 cases in each group. The control group was given lifestyle instructions for diet and exercises, and the medicine group was treated with SXC orally besides the instructions for lifestyle. The treatment for both groups covered 12 weeks. Before and after treatment, we observed the outcomes including scores of phlegm-dampness, body weight, waist circumference, hip circumference, blood pressure, fasting blood glucose, serum lipid profile, urine acid, body fat accumulation and distribution, and visceral fat accumulation. Results(1) The scores of phlegm-dampness were decreased significantly in both groups after treatment (P<0.05 or P<0.01), and the decrease was obvious in the medicine group(P<0.01).(2) Body weight and BMI were decreased significantly in both groups after treatment(P<0.01), and the decrease was obvious in the medicine group(P<0.05). Waist circumference was decreased significantly in the medicine group(P <0.05) but stayed unchanged in the control group(P>0.05). Hip circumference was decreased significantly in both groups(P <0.05 or P<0.01) , but the difference between the two groups was insignificant(P>0.05).(3) Systolic pressure and diastolic pressure were decreased significantly in both groups (P<0.01). But the difference of blood pressure decrease between the two groups was insignificant(P > 0.05).(4) Fasting blood glucose, 2-hour blood glucose after oral glucose tolerance test, serum lipid profile and urine acid remained unchanged in both groups after treatment (P>0.05). (5) The general body fat accumulation of both groups was decreased significantly after treatment (P <0.05 or P<0.01), and the decrease was obvious in the medicine group(P<0.01). Body fat accumulation in legs, trunk and gynoid region were decreased significantly in both groups after treatment(P<0.05 or P<0.01), but the difference of fat accumulation decrease between the two groups was insignificant(P>0.05). Waist fat accumulation had no significant decrease in the control group (P > 0 . 05), but was decreased in the medicine group (P<0.01). Visceral fat accumulation was decreased significantly in both groups after treatment(P<0.01), and the decrease was obvious in the medicine group (P<0.01). Conclusion In addition to its contribution to body weight loss, SXC also contribute to the reduction of visceral fat accumulation in obesity patients with phlegm-dampness constitution .

BACKGROUND:Basic fibroblast growth factor (bFGF) plays an important role in the ligament tissue healing process, and bone marrow mesenchymal stem cel s transfected with growth factors can be used as seed cel s in ligament tissue engineering.
OBJECTIVE:To observe biological effect of bone marrow mesenchymal stem cel s transfected with recombinant adenovirus vectors carrying bFGF in three-dimensional co-culture with ligament fibroblasts.
METHODS:Passage 3 bone marrow mesenchymal stem cel s were divided into three groups:control group, Ad-EGFP group and Ad-bFGF group. Under a phase contrast microscope, the changes in cel morphology were observed and the rate of transfection was analyzed by flow cytometry. Proliferation of bone marrow mesenchymal stem cel s and ligament fibroblasts was analyzed by MTS, the expression of bFGF protein in bone marrow mesenchymal stem cel s was determined by ELISA. Scleraxis, col agen type I, col agen type III, decorin and cartilage oligomeric matrix protein levels were detected in BMSCs and ligament fibroblasts using real-time fluorescent quantitative PCR.
RESULTS AND CONCLUSION:Recombinant adenovirus-mediated bFGF gene could transfect bone marrow mesenchymal stem cel s efficiently. After co-culture for 3, 6 days, compared with the control group and Ad-EGFP group, in the Ad-bFGF group, the proliferation ability of bone marrow mesenchymal stem cel s and ligament fibroblasts was enhanced (P<0.01), the expression of bFGF protein in supernatant was obviously higher (P<0.01), the col agen type I, col agen type III, decorin and cartilage oligomeric matrix protein mRNA expression decreased in the ligament fibroblasts (P<0.01), but the mRNA expression of Scleraxis, col agen type I, col agen type III in bone marrow mesenchymal stem cel s increased (P<0.01). The results suggest that the co-culture of Ad-bFGF-transfected bone marrow mesenchymal stem cel s with ligament fibroblasts promotes the proliferation of ligament fibroblasts while decreases the col agen synthesis at the same time, and stimulates the proliferation and differentiation of bone marrow mesenchymal stem cel s into ligament fibrolasts.

Objective:To study the relationship between the levels of serum insulin,C-reactive protein(CRP),Tumor Necrosis Factor(TNF-?),insulin resistance index,blood fat,and phlegm-stagnation stasis syndrome of metabolic syndrome(MS),so as to discuss the signifi cance of phlegm-stagnation stasis syndrome in treatment based on syndrome differentiation of MS,in order to fi nd the objective evidence of differentiation of symptoms and signs of TCM of MS.Methods: In this study,54 cases with MS were divided into groups of phlegm-stagnation stasis syndrome and non-phlegm-stagnation stasis syndrome according to the clinical symptoms,tongue demonstration and pulse tracings.There were 25 cases in phlegm-stagnation stasis group,29 cases in non-phlegm-stagnation stasis group.The levels of serum insulin,CRP,TNF-?,blood fat were checked,the insulin resistance index was calculated.Results:The levels of serum insulin,CRP,TNF-? of the two groups of metabolic syndrome were signifi cantly higher than those of the healthy persons(P

Partial fibulectomy is widely used in fibula transplantation and the treatment of fibular tumor and injury. After follow-up surveys and biomechanical experiments, many authors believe it is important to pay attention to the postoperative complications in leg，which now still remains in dispute. For the first time finite element analysis is used to find out the mechanical characteristics of crural bone before and after partial fibulectomy. Our results show that resection would alter significantly the stress distribution in tibia, fibula and the medial & lateral parts of talus, so influent the ankle joint stability. Causes of postoperative complications were also discussed.

Objective To investigate the clinical and pathological features of limb-girdle muscular dystrophy type 2B(LGMD2B).Methods The clinical data and the pathological result of skeletal muscle in five patients with LGMD2B were analyzed retrospectively.Results Five patients presented muscle atrophy and weakness(four limbs in three patients and both lower limbs in two patients),and the chronic onset,and the progressive deterioration.The pathological examination showed that the muscle fibers degenerating,necrotic and regenerating in different extents were observed,and the infiltration of inflammatory cells were appeared on all of cases.Immunohistochemical stains showed that the expression of anti-dysferlin monoclonal antibody was negative,anti-Dystrophy,Sarcoglycan and dystroglycan monoclonal antibodies were positive normaly,anti-CD8+T cell monoclonal antibody was negative,and anti-MHC-1 monoclonal antibody was up-regulated in five patients.Conclusions The clinical characters of LGMD2B are chronic onset,progressive muscle atrophy and weakness in four limbs or both lower limbs.The pathological characters of LGMD2B are similar to the changes of polymyositis.

Objective To investigate the relationship between the expression of PDGF and PDGFR and MVC in human gastric carcinoma. Methods The expression of PDGF and PDGFR in 57 cases with gastric carcinoma was detected by immunohistochemical method of avidin-biotin complex in formalin-fixed and routinely paraffin-embedded tissue sections. Results The expression of PDGF and PDGFR was significantly related to the infiltrative depth and regional lymph nodes metastasis of gastric carcinoma. The positive rates of PDGF and PDGFR in the cases with invasive depth over 2/3 muscular layer were 61 8% and 58 8% respectively, which were obviously higher than those(26 1%, 26 1%) in the ones with invasive depth less 2/3 muscular layer(P

0.05). The positive rates of PDGF and PDGFR in the HCC patients with the tumor emboli of portal vein and/or biliary duct were 76.9% and 76.9%, respectively, which were significantly higher than those(25.0% and 16.7%, respectively) in the ones without(P