BACKGROUND:Usual mechanics experiment approach cannot be applied directly to human body and the inter-comparability of models is low.Therefore finite element numerical simulation to mechanical behavior of human body has become an effective method for better understanding of the human body.OBJECTIVE:To establish a three-dimensional finite element model of femoral osteoporosis.METHODS:According to the average Chinese femur parameters,1 male patient with severe osteoporosis,aged 86 years,with no hip joint diseases,was selected.The data of femoral osteoporosis was obtained by means of spiral CT scanning.The graphical data were processed by the Mimics 11.1 (a graph processing software),and the outline curve data of femoral bone cortex inside and outside surface were obtained.The curve data were imported into the Unigraphic NX4.0 for solid modeling.The femur three-dimensional model composed of the cortical bone,cancellous bone and medullary canal was obtained.The model data were imported into the Ansys 11.0 for operations such as assigning,meshing,and contact interactions to establish three-dimensional finite element model of osteoporotic femur.RESULTS AND CONCLUSION:Three-dimensional finite element model of femur of osteoporosis was successfully established,which provides a reliable method for the construction of finite element model of femoral osteoporosis,and creates conditions for investigating femoral osteoporosis fracture fixation method and joint replacement.

BACKGROUND:Alendronate is a new generation of diphosphate,which is the second generation of osteoporosis drugs.It is widely used to treat diseases related to increase of bone absorption in clinic.OBJECTIVE:To observe the effect of alendronate on the proliferation and the mRNA expression of osteoprotegerin(OPG) and receptor activator of nuclear factor kappa B ligand(RANKL) of human osteoblasts.DESIGN,TIME AND SETTING:A single sample observational experiment was performed at the Basic Research Institute of Chongqing Medical University from November 2007 to March 2008.MATERIALS:Osteoblasts were isolated from cancellous bone in a surgical operation.Alendronate was the product of Merck Sharp & Dohme S.p.A.METHODS:Osteoblasts were cultured with various concentrations of alendronate(1?10-9,1?10-8,1?10-7,1?10-6,1?10-5,1?10-4 mol/L).Osteoblasts cultured without alendronate were assigned as controls.MAIN OUTC0ME MEASURES:①The morphology and growth of osteoblasts were observed.②Effect of alendronate on the proliferation of osteoblasts were detected by MMT method.③The effect of various concentrations of alendronate on the mRNA expression of OPG and RANKL were detected by using RT-PCR.RESULTS:1?10-5 and 1?10-4 mol/L alendronate inhibited the proliferation of osteoblasts.1?10-9-1?10-6 mol/L alendronate promoted the proliferation of osteoblasts,and the 1?10-8 mol/L alendronate had the strongest effect.Alendronate inhibited RANKL mRNA expression in a concentration-dependent manner,1?10-5 mol/L alendronate had a strongest effect at 72 hours after culture(P

Objective To investigate the clinical application of fast track surgery in patients undergoing elective colorectal carcinoma surgery. Methods Seventy patients with colorectal carcinoma requiring colorectal resection were randomized into two groups: fast-track group (35 cases) and conventional care group (35 cases). Results Sixty-two patients finished the study, 32 cases in fast-track group and 30 cases in conventional care group. The median and average time to the first passage of flatus (2±1 vs. 4±2, P<0.01), the first passage of stool (3.8±1.6 vs. 6.4±2.5, P=0.0007), resumption of normal diet [(4±2) vs. (8.2±2.2), P<0.01] and the length of postoperative stay (6±1 days vs. 11.7±3.8 days, P<0.01) were much shorter in the fast-track group than in the conventional care group. The preoperative incidence of thirst (2/32 vs. 23/30, P<0.01), hunger (5/32 vs. 20/30, P<0.01) and postoperative infectious complications (2/32 vs. 8/30, P=0.04) were much lower in the fast-track group than in the conventional care group. Conclusion Fast track surgery in patients undergoing elective colorectal resection was safe and effective.

Objective To investigate the prognostic significance of extended resection for locally advanced colorectal carcinoma. Methods Clinical data of 960 cases of colorectal cancer hospitalized for surgery between Jan 1995 and Dec 2002 were reviewed, and complication rates, perioperative mortality, 5-year survival were calcualated, prognostic factors were analyzed using Cox regression model. Results Sixty-six patients with locally advanced colorectal carcinoma were treated with extended resection, accounting for 6.9% of the total cases. Surgical complication rate in this subgroup was 27.3% (18/66), relatively higher than that of conventional resection for colorectal carcinoma (?~2 =8.82, P=0.002). The perioperative mortality was zero. Pathology showed that carcinoma invasion into the adjacent organs resected en bloc was 31% (27/88), the 5-year survival rate was 62%. The tumor spreading into the adjacent organ (Wald=7.42,P=0.005) and lymph node status (Wald=4.55, P=0.035) were found to be the independent prognostic factors. Conclusions Extended resection for locally advanced colorectal carcinoma resulted in a favorable prognosis. Postoperative complication was relatively high, but still acceptable.

Objective To investigate the clinicopathological difference and prognosis of colorectal adenocarcinomas including mutinous, Signet-ring cell, papillary and tubular carcinomas. Methods Two thousand and eighty-nine patients with colorectal cancer underwent colorectal operation between August 1994 and April 2007. The clinicopathological characteristics of mucinous adenocarcinoma (n=144), signet-ring cell carcinoma (n=25), papillary and tubular carcinomas (n= 1837) were compared expect of other types of cancer (n = 83). The single factor and Logistic regression methods were used to analyze the clinicopathological parameters that influence the prognosis of colorectal cancer such as age, location of the tumor, staging, peritoneum and pathological typing. The survival rates of patients with above three types of adenocareinomas were analyzed. Results The mean age of onset was lowest in patients with mutinous adenocarcinomas [(54. 20 ± 16.25) years] compared with that in patients with signet-ring cell cancer [(40.43 ± 12.88)years] or papillary and tubular carcinomas [(58. 73 ±13.62)]. There were significant differences in gender, size and location of the tumor, TNM staging, peritoneal metastasis, lymph node involvement and adjacent organ invasion among three groups (all P values <0.05). The single factor and Logistic regression analysis revealed that both mucinous adenocarcinoma and signet-ring cell carcinoma were risk factors ot prognosis. The patients with mucinous adenocarcinoma or signet-ring cell tumor were poor in long-term overall survival in comparison with patients with papillary and tubular carcinoma (P<0. 001). Conclusions The colorectal mucinous and signet-ring cell adenocarcinomas are risk factors for prognosis of colorectal cancer, which imply the poor outcome.

Objective To investigate the effects of estrogen on mismatch repiar gene expression in colonic mucosa in vivo. Methods A total of 42 healthy individuals underwent colonoscopy were enrolled in the study. Half an hour before colonoscopy examination, blood sample was taken for determining the serum estradiol (E2) level. N ormal colonic mucosal tissues determined by naked eye under colonoscopy examination were taken in the right hemi colon to detect HMLH1 and hMSH2 gene expression by semi-quantitative RT-PCR and immunohistochemistry staining. Then the correlation of serum E2 levels with hMLH1 and hMSH2 expression in colonic mucosa was analyzed. Results A bimodal curve was presented for the correlation between serum E2 level in healthy individuals and hMLH1 expression in colonic mucosa. A strong positive correlation of E2 level with hMLH1 expression in normal colonic mucosa was observed when serum E2 level was more than 45 pg/ml (For mRNA, P=0. 003, r=0. 701; for immunohistochemistry positivity index, P=0. 000, r=0. 874).However there was no correlation between E2 level and hMSH2 expression. Conclusion High serum E2 level might increase the hMLH1 gene expression in colonic mucosa in vivo.

Objective To explore clinical features,prognosis and study related cancer types in patients with familial gastric carcinoma. Methods Nine families of ICG-HGC and 3 families of suspected-ICG-HGC according with International Collaborative Group on Hereditary Gastric Cancer standard were collected and their pedigree trees were drawn.Clincial features and prognosis of ICG-HGC and suspected-ICG-HGC families were analyzed.and the related cancer types of ICG-HGC and suspected-ICG-HGC kindreds were investigated. Resuits The morbidity of ICG-HGC and suspected-ICG-HGC was 0.99%;The age of patients among the propositi of 12 kindreds were 29～65 years old with the mean age of 56 years old.Among 11 kindreds,there were 45 cases of cancers including 2 cases of multiple cancers.There were 30 foci of gastric cancer,most of which were located in lower and middle third of the stomach,with pathologic type of adenocarcinoma in poor to moderate differentiation.There were totally 15 extrastomach tumors including 7 colorectal cancers.Four cases of 11 kindreds had survived for 3 years including 1 case surviving for more than 10 years. Conclusion The familial gastric cancers in southern China have special characteristics such as poorly pathologic differentiation,advanced cancer stage,early age of onset,distal end of the stomach in location and high incidence of related tumors in colorectum.

Objective To investigate the application of computer-aided 3D reconstruction and rapid prototyping(RP) technique in the correction of prominent mandibular angle.Methods Computer tomography scanning and 3D reconstruction were performed on 15 square face patients with prominent mandibular angles,then their actual mandible models were made by RP techniques.Surgical programs were made according to the model,including partial mandibular angle osteotomy,outer mandible table sagittal splitting osteotomy,chin augmentation with autogenous mandibule bones,and so on.In 15 cases,mandibular angle partial cutting was performed in 5 cases,sagittal splitting osteotomy in 6 cases,and mandibular angle partial cutting combined with splitting osteotomy in 4 cases.The autogenous mandibule bones were transplanted for chin augmentation in 3 chin microsomia patients.All the cases were treated according to the position and range set by the RP model.Results All the mandibular models produced by RP techniques were real and complete,which could directly and precisely show the state of the mandible.The operations completed smoothly and accomplished with the expected outcomes designed before operation.In all cases,the width of lower face was efficiently reduced and the face was symmetrical after operation.The follow-up period ranged from 3 months to 1 year in 12 patients,during which their facial appearances were in good condition and the results were satisfactory.Conclusion RP techniques is helpful in precise representation of the state of mandible,which providing ideal surgical models for accurate evaluation of prominent mandibular angle,design of surgical procedures as well as surgery instruction.It can provide good assistance to facial contour plastic surgery.

Objective To analyze mutations in the ATP2A2 gene in a Kazakh family with Darier's disease.Methods Clinical data were collected from 49 members from a family with Darier's disease,and peripheral blood samples were obtained from 44 family members and 100 unrelated healthy people.Genomic DNA was extracted from these blood samples.PCR and DNA sequencing were performed to detect mutations in the ATP2A2 gene.Results Darier's disease was inherited in an autosomal dominant manner in this family.A G→A heterozygous mutation (1288-1G→A) was identified at position 1288-1 at the splice site in exon 12 of the ATP2A2 gene in 11 patients in this family,but not in 33 healthy members or 100 healthy controls.Conclusion Darier's disease in this family may be caused by the heterozygous mutation (1288-1G→A)at the splice site in exon 12 of the ATP2A2 gene.

Objective To explore the correlation between COX-2 and Ki-67 expression and microvessel density in primary gastric cancer tissue and clinicopathological parameters and to investigate their effect on postoperative gastric cancer recurrence. Methods Forty-eight postoperative recurrent gastric cancer patients were enrolled in this study, their clinicopathologic characters of primary tumors were analyzed retrospectively and compared with 48 cases without recurrence. Expression of COX-2 and Ki-67 and microvessel density ( MVD) in gastric cancer tissue were detected by immunohistochemical method. Risk factors correlated with tumor recurrence were studied by univariate and multivariate analysis. Results Expression of COX-2, Ki-67 label index (LI) and MVD were correlated with each other, and they were all correlated with depth of invasion and TNM stages in gastric cancer tissue. Patients with pelvic metastatic lymph node, cancer invasion to serosa, of Borrmann III or IV, high COX-2 and MVD expression are on high risk of recurrence (P