Artificial bone replacement has made an important contribution to safeguard human health and improve the quality of life. The application requirements of rapid prototyping technology based on reverse engineering in individualized artificial bone with individual differences are particularly urgent. This paper reviewed the current research and applications of rapid prototyping and reverse engineering in artificial bone. The research developments and the outlook of bone kinematics and dynamics simulation are also introduced.
Biomedical Engineering ; Bone Substitutes ; Bone and Bones ; Humans

Objective To evaluate the diagnostic value of different sequences of magnetic resonance imaging (MRI) in repaired meniscus.Methods From September 2002 to December 2008,118 patients (130 menisci) underwent arthroscopic meniscus suture in our hospital,including 94 males and 24 females,aged from 15 to 50 years (average,25.7t7.5 years).All patients underwent MRI and second-look arthroscopy postoperatively.Different sequences of MRI were taken to evaluate the grade of meniscal signal at repaired site and the slices involved by grade 3 signal.The diagnostic sensitivity,specificity,accuracy,positive predict value (PPV) and negative predict value (NPV) were calculated for each sequence by using second-look arthroscopy as the gold standard.Results The total healing rate was 80.8％ (105/130) by second-look arthroscopy,which was higher than that by different sequences of MRI.The integrated T2 sequence held the highest diagnostic value,and the sensitivity,specificity,accuracy,PPV and NPV were 76.0％,71.4％,72.3％,38.8％ and 92.6％,respectively.According to the second-look arthroscopy result,the menisci were divided into the healed group and unhealed group.In the healed group,28.6％ of cases (30/105) showed grade 3 signal in MRI,which was less than that (76.0％) in the unhealed group.The rate of the new grade 3 signal (8.6％) and the slices involved by grade 3 signal (0.8±1.0) in the healed group were less than those (16.0％ and 3.0±2.0) in the unhealed group.Conclusion The diagnostic value of the integrated T2 sequence is encouraging with high sensitivity,specificity and accuracy.The new grade 3 signal in the repaired meniscus usually implies that the meniscus is not healed.

Objective To study the feasibility of the Fe3O4-loaded lipid perfluorooctylbromide nanoparticles (Fe3O4-PFOB) for enhanced ultrasound imaging.Methods The Fe3O4-PFOB nanoparticles,incubated with RAW264.7 macrophage cells,were monitored by microscope and ultrasound.Twelve SD rats were randomized into two groups,Fe3O4-PFOB group and PFOB group.Ultrasound imaging of rats' liver was performed before and after intravenous injection of the contrast agents.The liver echogenic intensity was quantified by DFY ultrasound quantified system analysis.Results Incubation of the Fe3O4-PFOB nanoparticles with macrophages resulted in the uptake of Fe3O4-PFOB by macrophages.Macrophages loaded with Fe3O4-PFOB exhibited enhanced echogenicity in vitro.In in vivo imaging,Fe3O4-PFOB produced better and prolonged ultrasound enhancement of rats' liver compared to PFOB nanoparticles.Conclusions Fe3O4-PFOB nanoparticles could enhance ultrasound imaging and may potentially serve as a multimodal probe for ultrasound,CT and MR imaging.

Objective To evaluate the clinical application value of the PPH in the treatment of severe prolapsed hemorrhoids.Method Forty cases with severe prolapsed hemorrhoids underwent improved PPH with homemade stapler.Results The operating period of time was 10～20min and the mean hospitalization period of time was 4 days.All the 40 cases were cured,of whom bleeding in 2 cases,postoperative malaise at the lower abdomen in lO cases,urinary retention in 11 cases,slight pain in 20 cases.After following-up for 3～15 months,there were no such complication as prolapse again,and no anal stricture,fecal incontinence,etc happened.Conclusion The improved PPH is a safe and effective new method in the treatment of severe prolapsed hemorrhoids.

Objective This study has explored the role of antibody against annexin A2 in patients with antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE). Methods Using purified recombinant annexin A2, IgG anti-annexin A2 antibody was measured by ELISA in 101 APS patients, 41 SLE patients with thrombosis, 124 SLE patients without thrombosis and 120 healthy controls. Results The positive rate of IgG anti-annexin A2 antibody in APS patients and SLE patients with thrombosis was 21.8%, 26.8%, respectively, they were all significantly higher than in SLE patients without thrombosis (6.5%). IgG anti-annexin A2 antibody was associated with thrombosis and/or pregnancy morbidity (P<0.01). Conclusion Anti-annexin A2 antibody is associated with thrombosis and/or pregnancy mnrbidity. It suggests that anti-annexin A2 antibody may be helpful in identifying in some potential AIRS.

Objective To find the effect of alter-expressed PER2 on proliferation,apoptosis and other clock genes expression in human oral squamous cell carcinoma SCC15 cells.Methods Short hairpin RNA interference was used to knockdown PER2 in SCC15 human oral squamous cell carcinoma cells.Flow cytometry analysis was used to testify the cell proliferation and apoptosis.Quantitative real-time PCR was used to testify the mRNA expressions of PER3,BMAL1,DEC1,DEC2,CRY2,TIM,RORα,NPAS2,PER1 and REV-ERBα.Results The proliferation was enhanced and apoptosis was decreased after PER2 knockdown in SCC15 cells (P<0.05).The mRNA expression of PER3,BMAL1,DEC1,DEC2,CRY2,TIM,RORα and NPAS2 was significantly down-regulated,and the mRNA expression of PER1 and REV-ERBα was significantly up-regulated (P<0.05).Conclusions Clock gene PER2 plays an important role in regulating other clock genes of the clock gene network in cancer cells,PER2 knockdown can enhance proliferation and recede apoptosis of cancer cell.

Aim: To search for new compounds with stronger anti-inflammatory activities and less gastrointestinal side effects. Methods: 2-(2, 4-Dichlorophenyl) -3-(3, 5-dimethoxyphenyl) - propenoic acid(Ⅰ) was converted to amides(Ⅱ). Their anti-inflammatory activities against xylene-induced mice ear swelling were evaluated. Results: Twelve target compounds (Ⅱ_(1-12)) were synthesized, and their structures were confirmed by IR,~1H NMR and HR-MS.Ⅱ_3 exhibited significant anti-inflammatory activity compared with CMC-Na ( P < 0. 01) and aspirin ( P < 0. 05). Conclusion: Compound Ⅱ_3 deserves further investigation.

Objective To explore the relationship between maternal pre-pregnancy body mass index (BMI) and neonatal birth weight in women with gestational diabetes mellitus (GDM). Methods From the pregnant women who received prenatal care and delivered at the Department of Obstetrics and Gynecology of Peking University First Hospital between May 1, 2012 and November 1, 2013, 550 GDM women aged 20-49 years and with single gestation were enrolled in this study. According to the pre-pregnancy BMI, the GDM women were divided into overweight group (BMI ≥ 24.0, n=145) and non-overweight group (BMI < 24.0, n=405). Gestational weight gain, glucose level of 75 g oral glucose tolerance test, glucose control, delivery mode and neonatal birth weight were compared between the two groups. The influencing factors for macrosomia and the relationship between maternal pre-pregnancy BMI and neonatal birth weight were analyzed. Independent sample t-test, Chi-square test, multivariate Logistic regression and Pearson correlation analysis were used for statistical analysis. Receiver operating characteristic (ROC) curve was used to determine the optimal threshold of pre-pregnancy BMI to predict macrosomia. Results Compared with the data of non-overweight group, fasting glucose level [(5.1±0.5) vs (5.3±0.5) mmol/L, t=-4.599], 1 h glucose level [(9.4±1.7) vs (9.8±1.6) mmol/L, t= - 2.742], proportion of poor glucose control [20.5% (83/405) vs 33.1% (48/145), χ2=8.281], proportion of cesarean delivery [37.8% (153/405) vs 55.2% (80/145), χ2=13.160], neonatal birth weight [(3 306±424) vs (3 476±545) g, t=-3.374], and ratio of macrosomia [5.4% (22/405) vs 16.6% (24/145), χ2=16.291] were all higher in overweight group (all P < 0.01). The mean gestational weight gain per week in overweight group was significantly lower than in non-overweight group [(336±123) vs (402±131) g, t=5.136, P < 0.01]. Pre-pregnancy overweight (OR=4.009, 95%CI:2.039-7.881), gestational weight gain per week (OR=1.003, 95%CI:1.001-1.005) and fasting glucose level (OR=2.285, 95%CI: 1.326-3.938) were the influencing factors for macrosomia (all P < 0.01). Pre-pregnancy BMI of GDM women was positively related with neonatal birth weight (r=0.179, P < 0.01). Pre-pregnancy BMI ≥ 22.8 was defined as the optimal threshold to predict macrosomia (ROC area under curve=0.691). Conclusions Maternal pre-pregnancy overweight is a significant risk factor for macrosomia in women with GDM. GDM women with pre-pregnancy overweight should control glucose level and weight gain during pregnancy in order to reduce the risk of macrosomia.

Objective To investigate the association between serum ferritin(SF) level at early and mid trimester of pregnancy and gestational diabetes mellitus (GDM) and insulin resistance (IR).Methods A total of 192 cases of women who were accepted antenatal examination from the first trimester of pregnancy at Yueqing People Hospital from July,2012 to October,2013 was prospectively analyzed and followed up.All cases were divided into two groups:96 cases of GDM pregnant women who were diagnosed as GDM at mid trimester of pregnancy as GDM group,and 96 cases of pregnant women with normal glucose tolerance at the same time as the control,normal glucose tolerance (NGT group).The differences in clinical data were compared between two groups.The relationship between SF level and fasting plasma glucose (FPG),fasting insulin (FINS),homeostasis model assessment insulin resistance (HOMA-IR),and C-peptide was investigated with Spearman rank correlation analysis.The predictive values of SF and relative variables to GDM were calculated by receiver operating characteristic curve (ROC) or Logistic regression analysis.Results (1) There was statistically significant difference in body weight and body mass index (BMI) at prepregnancy and mid trimester of pregnancy,Hb,FPG,FINS,SF,and C-peptide at the first trimester of pregnancy,SF level and FPG and HOMA-IR and C-peptide at mid trimester of pregnancy between two groups (P ＜ 0.01 or P ＜ 0.05).(2) As showed by Spearman rank correlation analysis,there was statistical correlation between SF at mid trimester of pregnancy,and FPG,FINS,HOMA-IR and C-peptide (P ＜0.01 or P ＜ 0.05);while no statistical correlation was found between SF at the first trimester of pregnancy and the same factors above (P ＞ 0.05).(3) The area under the ROC curve of SF at mid trimester of pregnancy for GDM was 0.653.The sensitivity and specificity were 68.8％ and 59.4％ in predicting GDM at the cut-off value of 16.61 ng/ml.As showed by Logistic regression analysis,high level of SF at mid trimester of pregnancy was a independent risk factor for GDM.Odds ratio (OR) was 1.032 (95％ CI:1.008 ～ 1.058,P ＜ 0.01).Conclusions The relationship between SF at different trimester of pregnancy and GDM is variant.There is relationship between high level SF of mid trimester of pregnancy in GDM pregnant women and IR.The level of SF might predict the occurrence of GDM.

Objective To investigate the distribution of the prevalence of albuminuria in elderly population of a community in Tianjin and analyze the situation of their early renal injury and its clinical and environmental risk factors.Methods The morning spot urine sample and the clinical data from 2 050 old population (aged ≥ 60 years)who took part in healthy examination were collected.The concentration of urine albumin and creatinine were tested,and the albumin/creatinine ratio(ACR)was calculated.We analyzed the prevalence of albuminuria,and used logistic regression to analyze the odd ratio(OR) of risk factors.Results In the 2 050 participants,the prevalence was 1162 cases (56.69％) for hypertension,264 cases (12.86％) for diabetes and 568 cases (27.71％) for albuminuria.The prevalence of ACR ＞ 30 mg/g was lower in men than in women (21.61％ vs.32.55％,P＜0.001).The OR for increased ACR was 1.45 in 70-79y subjects as compared with 60-69y subjects,and the OR was 1.89 in ＞80y old people.The OR of increased ACR was 2.03 in ＞80y old people after adjusting gender.Body mass index and waist circumference were not the risk factors of increased ACR after adjusting confounding factors.There was an association between the prevalence of albuminuria and triglycerides(OR=1.19),hypertension(OR=1.68),diabetes(OR=1.95).ACR value was increased along with increased number of cigarettes,however,there was also no association between smoking and albuminuria(P＞ 0.05).Physical activity could reduce the risk of albuminuria,the OR of ACR＞30 mg/g in those undertaking a activity once daily was 0.52 (P =0.027) Conclusions There is a high prevalence of albuminuria in elderly population(higher in female than in male) in a community of Tianjin.Hypertension and diabetes have the greatest influence on ACR.Additionally,the physical activity once daily can reduce the risk of albuminuria.