To sum up the methods which can be used to prevent dislocation after total hip replacement.Recent original articles about the reasons of dislocation and methods which were used to treat or prevent dislocation were extensively reviewed,and retrospective and comprehensive analysis was performed.Dislocation after THA can be reduced by careful assessment of patients,selecting suitable prosthesis,improving the position of prosthesis and avoidance risk movements.Dislocation after THA can be reduced by careful pre-,intra-,and postoperative assessment.

Objective To explore the value of the percentage of necrotic surface area in predicting collapse of osteonecrosis. Methods 15 hips of avascular necrosis of the femoral head(ANFH) in 9 patients underwent MRI scan. On the MRI films, the percentage of necrotic surface area were calculated. While on the specimens of the 15 hips, the percentage of necrotic surface area were also measured. In 16 hips of 8 patients of ANFH with serials MRI at mean 18.9 months intervals (range, 6-41 months), the percentage of necrotic surface area were calculated and compared. In 38 hips of 27 patients without collapse, the percentage of necrotic surface area and the index of necrosis were calculated on MRI films. Follow-up was terminated when crescentic sign illustrated on X-ray film or CT demonstrated articular facet collapse. Those hips without collapse were followed up more than 24 months. The value of the percentag of necrotic surface area and the index of necrosis in predicting collapse of osteonecrosis was observed. Results The percentage of necrotic surface area were 63.23%?10.16% on specimens and 63.60%?7.78% on MRI films respectively. There were no significant differences between them. The percentage of necrotic surface area on specimens were coincidence with those on MRI. In the 16 hips with serials MRI; the percentage of necrotic surface area were 52.37%?19.91% on the first MRI films, 51.70%?21.29% on the second. There were no significant differences between them. This result revealed that the percentage of necrotic surface area did not vary with the extension of course of disease. In the 38 cases of early necrosis, 28(73.7%) hips collapsed and 10(26.3%) hips did not. The relative risk of the percentage of necrotic surface area was 1.043, and the relative risk of the index of necrosis was 1.020. No significant difference was found in ARCO staging for patients with or without femoral head collapse. It demonstrated that whether ischemic necrotic femoral head collapse or not had no relation with its ARCO stage. Conclusion The percentage of necrotic surface area can be used as more accurate predictor for future collapse.

[Objective]To explore the causes and treatments of recurrent dislocation after total hip replacement.[Method]From July 1999 to January 2007,there were 47 cases of dislocation after total hip replacement.Thirteen cases were recurrent.CT and serial X-rays were taken to observe the position of prosthesis.The strength of their hip abductor was also tested.Stability test was used to value the stability of hip.Closed reduction,modular adjustments and revision were adopted according to patients,willingness,prosthesis and stability.[Result]All of the 13 patients had malposition.Eleven cases were tested with instability.Five cases were successfully treated by closed reduction.Despite dislocation reoccurred 1～2 times every year in 3 patients treated by closed reduction,patients felt satisfactory.In the 4 cases with modular revision procedure,2 cases changed the neck length,1 case used elevated liner and larger neck length,1 cases treated by using larger offset and adjusting abnormal liner.Another one treated by revision.[Conclusion]Malposition is the major causes of recurrent dislocation.The prosthesis test whowed instability.The treatments of recurrent dislocation after THA should use different ways according to the causes of dislocation,stability of prosthesis and the willingness of patients.

Objective By virtual screening in MDL,to search for a novel γ-secretase inhibitor.Methods A series of compounds were designed,synthesized,and evaluated based on pharmacophore model of γ-secretase inhibitors by virtual screening in MDL.Results The drug-likeness analytic data synthesized indicated that target compounds had drug-likeness.Each svnthesized compound was checked by IR spectroscopy,~1H and ~(13)C-NMR spectroscopy.Conclusion The designed compounds had better activity by model prediction.And the optimal compound showed a significant estimated activity value of 0.025 nmol/L and can be used as a lead for further drug development.

Objective: To use vertical and humidity correcting method to calibrate aerosol optical depth (AOD), and to explore the feasibility of calibrated-AOD as exposure index to measure the level of air pollutants from the ground and to establish the exposure-response relationship between calibrated-AOD and people's health outcomes.Methods: First of all, we interpolated AOD, PM2.5, relative humidity and planetary boundary layer height using Kriging method to obtain data at different locations and matched different data with respiratory death in Beijing by geographical coordinates.Then, the planetary boundary layer height and aerosol hygroscopic growth factor calculated based on relative humidity was used to calbrate the AOD.To compare the effects of calibrated-AOD and PM2.5, we used standardization method to get non dimensionless calibrated-AOD and PM2.5.At last, we used the generalized additive mixed model (GAMM) to estimate the acute effects of calibrated-AOD and PM2.5 on respiratory death and chronic obstructive pulmonary disease (COPD) death, after controlling the time trend, temperature and humidity effects, days of the week effect and holiday effects.Results: The correlation coefficient between calibrated-AOD and PM2.5 was 0.72.The effects of calibrated-AOD on respiratory death and COPD death was the strongest at lag 0-3, one unit of calibrated-AOD increases was associated with 3.64% (95%CI: 0.58%-6.78%) increase of respiratory death and 4.92% (95%CI: 1.81%-8.14%) increase of COPD death.As for PM2.5, the strongest effects appeared at lag 0-1, one unit of PM2.5 (about 155 μg/m3) increases was associated with excess risks of 3.96% (95%CI: 0.82%-7.19%) and 6.12% (95%CI: 1.44%-11.02%) for respiratory death and COPD death respectively.Compared with PM2.5, the effects of calibrated-AOD on respiratory death and COPD death had narrower confidence intervals.The calibrated-AOD was sensitive to capture the lag effects, and the cumulative lag effects of calibrated-AOD were all significant on multiple lag days which indicated that the calibrated-AOD was sensitive to capture cumulative lag effects of air pollutants on respiratory death and COPD death as well.Conclusion: We believe that calibrated-AOD can be used as an index to reflect the effects of air pollutants on respiratory death in Beijing.In the absence of ground monitoring, calibrated-AOD can be used to mea-sure the relationship between air pollutants and some health outcomes.

Objective:To establish a method for the determination of trace nickel in agomelatine. Methods:An inductive coupled plasma atomic emission spectrometry method was applied in the determination at 221. 648 nm. The sample solution was prepared by the ignited residue of agomelatine. The content of nickel was determined using the standard curve. Results:The linear range was 0. 025-1. 000 μg·ml-1(r=0. 999 8). The RSD of precision was 0. 63%. The detection limit was 0. 000 8μg·ml-1. The quantitative limit was 0. 003μg·ml-1 . The average recovery was 99. 4% with RSD of 2. 20%. The RSD of repeatability was 1. 33%. Conclusion:The method is simple, sensitive and accurate in the determination of trace nickel in agomelatine.

Objective To explore the roles of PKCθ(protein kinase Cθ)signaling pathway on the activation,proliferation and TH1/TH2 cytokines production of the γδT lymphocytes stimulated by Mycobacterium tuberculosis antigen(Mtb-Ag) in vitro.Methods Peripheral blood mononuclear cells(PBMC)were pretreated with or without Rottlerin at 5.0 μmol/L,and stimulated with Mtb-Ag and cultured in rhIL-2 containing medium.After different time of culture,activation molecules and cytokines production of γδT cells were measured by flow cytometry.The proliferation proportion and the percentage of each generation of γδT cells were determined by carboxylfluoreseein diacetate succinmidyl ester(CFSE)labeling technique and flow cytometry.Results After 3d of stimulation with Mtb-Ag,the expression rates of CD69 and CD25 of γδT cells were 46.2%and 45.6%,respectively.Pretreatment of 5.0 μmol/L Rottlerin markedly inhibited the both expressions of CD69 and CD25 in γδT cells(P＜0.01).After stimulation and expansion in vitro for 5,10,and 15 d,the percentages of the γδT cell were 9.6%,54.6%and 82.4%,respectively.There was a few γδT cells in propagation on the 5th day of culture,and almost all γδT cell divisions were above 6 generations on the 10th and 15th day of culture.Pretreatment of the Rotflerin significantly suppressed the γδT cell proliferation,but after 10 d culture,there were still a few parts of γδT cells in propagation.Meanwhile,after 7,14,and 21d of culture,upon stimulation with PMA+Ionomycin,the IFN-γ producing-γδT cells were about 80%at all times.But only after 21d culture,IL-4-producing γδT cells was 2.6%.,The percentage of IFN-γ producing γδT cells markedly reduced in Rottlerin group(P＜0.01).IL-4 secretion of the γδT cells was almost completely blocked.Conclusion PKCO signal pathway involves in activation,proliferation and differentiation of the γδT lymphocytes stimulated by Mtb-Ag.

Objective To explore changes of metabolites in APP/ PS1 double transgenie mice of Alzbeimer disease (AD) by 1H-MR spectroscopy (1H-MRS) and the application value of in early diagnosis of AD.Methods 1H-MRS was performed in 35 APP/PS1 transgenie mice of AD ( study group) and 20 wild type mice ( control group) at age of 3, 6 and 9 months using a 7.0 T MR system.Sub-peak areas of N-acetyl aspartate (NAA), myo-inositol (mI) and creatine (Cr) in the cerebral cortex and hippocampus were measured, and the NAA/Cr and mI/Cr ratios were calculated.The changes in pathology between the two groups were compared.Using the lower limit of 95% confidence interval (CI) of the ml/Cr ratio and the upper limit of 95% CI of the NAA/Cr ratio of AD mice as the threshold, their influences on sensitivity,specificity and accuracy of various age groups of AD animals were compared.Comparison of the 1H-MRS indexes between study mice and wild type mice at each time point were conducted by a two-sample t test.Results The mean mI/Cr ratios of AD mice were 0.68± 0.03, 0.72± 0.04, and 0.77 ± 0.04 respectively at 3, 6 and 9 months of age; while they were 0.63 ± 0.04, 0.64 ± 0.03, and 0.64 ± 0.04 respoetively in control group, the difference was significant ( t = 2.814, 5.146, 14.437, P < 0.01 ).Compared with the control group, the mI/Cr ratio of the 3-month-old AD mice of the study group was significantly increased,and histological examination showed proliferation and activation of neuroglial cells in the cerebral cortex and hippoeampus.The mean NAA/Cr ratio were 1.17 ±0.08, 1.04 ±0.05, and 0.90 ±0.05 respectively at 3,6 and 9 months of age in study group, while they were 1.18 ±0.07, 1.16 ±0.07, and 1.18 ±0.08respectively in control group.There were no significant difference ( t = 0.752, P > 0.05 ) between the study group and control group at 3 months of age, and the NAA/Cr ratio decreased significantly only at 6 and 9 months of age ( t = - 8.514, - 5.646, P < 0.01 ).The immunohistochemical exam demonstrated the appearance of Aβ plaque.According to threshold of mI/Cr, the sensitivity of AD mice of 3, 6 and 9 months of age was 80% (28/35), 84% ( 26/31 ) and 85% ( 23/27 ), and the specificity was 85% ( 17/20 ),94% (17/18) and 100% ( 16/16), and the accuracy was 82% (45/55), 88% (43/49) and 91% (39/43),respectively.For NAA/Cr, the sensitivity of AD mice of 6 and 9 months of age was 84% (26/31) and 89% (24/27), and the specificity was 89% (16/18) and 100% (16/16), and the accuracy was 86% (42/49) and 93% (40/43), respectively.Conclusions NAA and mI are the most sensitive and specific markers for early assessment of AD, and change of mI is earlier than that of NAA.Quantitative analysis of mI may provide important clues for early diagnosis of AD.

Objective To evaluate the efficacy and safety of total knee arthroplasty (TKA) with 3D printing guild plate by comparing with conventional TKA. Methods From May 2014 to September 2014, 40 patients suffered primary unilateral TKA were received, in which there were 11 males and 29 females, aged from 57 to 82 years with an average age of 68.5±6.3 years. The subjects were divided into two groups randomly. One group was treated with TKA with 3D printing guild plate while the other group was treated with the conventional TKA. The blood loss, operation time, post?operative Hospital for Special Surgery (HSS) score, range of motion (ROM), lower limb mechanical alignment and incidence of complication were compared with insignificant differences. Results The operation time in the 3D printing TKA group (103.4±11.7 min) was lower than that in the conventional TKA group (124.5±21.6 min), which was statistically significant (t=3.838, P=0.000). The blood loss in the 3D printing TKA group (370.2±96.0 ml) was lower than that in the conventional TKA group (510.0±235.9 ml), which was statistically significant (t=2.454, P=0.019). The post?operative ROM of knee in the 3D printing TKA group was 104.3° ± 15.5° and that in the conventional TKA group was 103.5° ± 12.5° (t=0.169, P=0.867). HSS scores in the 3D printing TKA group and in the conventional TKA group were 88.5±5.7 and 89.4±4.8, which was statistically insignificant (t=-0.633,P=0.530). Mechanical alignment in the 3D printing TKA group was 2.9°±1.1° and that in the conventional TKA group was 3.0°±0.9°, which was not statistically significant (t=-0.317, P=0.753). No obvious complication occurred in two groups. Conclusion TKA with 3D printing guild plate has similar results to conventional TKA in HSS score, mechanical alignment and ROM of knee, but it shortens operation time and decreases the blood loss.