BACKGROUND:Early knee ioint prosthesis is used to relieve severe pain of patients．With continuous modification，the knee joint prosthesis with high flexion has developed．OBJECTIVE：To compare the clinical outcome between fixed platform high—flexion prosthesis and rotating platform high-flexion prosthesis following total knee arthroplasty．DESIGN：Non-randomized concurrent control trial of patients．PARTICIPANTS：Thirty-four patients(50 knees)with severe osteoarthritis underwent total knee replacement in Department of Bone and Joint,Tianjin Union Medicine Center from January to December 2006．METHODS：Of 34 patients，16(25 knees)underwent fixed platform high-flexion prosthesis replacement(LPS flexion，Zimmer，USA)，and 18(25 knees)underwent rotating platform high-flexion prosthesis replacement(PFC sigma RPF prosthesis．Johnson & Johnson,USA)．MAIN OUTCOME MEASURES：Knee joint function was evaluated using Hospital for Special Surgery Knee Score (HSS)before and 2 weeks，1，3 and 6 months after surgery．In addition，range of flexion of the knee was observed at 6 months postoperatively．RESULTS：Thirty-four cases completed the treatment and were followed up for 6 months．HSS scores of patients undergoing rotating platform high-flexion prosthesis replacement were higher than fixed platform high·flexion prosthesis replacement group at 2 weeks postoperatively(P<0．05)，while no differences were found in HSS scores at 1，3 and 6 months after surgery(P>0．05)．In addition，there were no significant differences in the range of flexion of the knee at 6 months postoperatively[(130．4±15．2)°，(129．9±13．8)°，P>0．05]．CONCLUSION：Fixed platform and rotating platform high-flexion prosthesis replacement exhibit similar early effects on severe osteoarthritis．

Objective To investigate the risk factors for mild cognitive impairment (MCI) in elderly people in Beijing.Methods Using multistage cluster random sampling,129 elderly people aged 60-80 years living around Dongzhimen communities were interviewed by mini-mental state examination (MMSE) and National Institute of Neurological and Communicative Diseases and Stroke/ Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria for screening MCI and Alzheimer's disease (AD).Results Thirty-seven cases (28.7%) had amnestic MCI (aMCI),thirty-six cases (27.9%) had AD,and fifty-six cases (43.4%) were with normal cognitive state (NCS).The age was older in aMCI patients or AD patients than in NCS[(67.6±7.5)y vs.(62.5±7.9)y,(67.6±7.5)y vs.(62.5±7.9)y,both P<0.01],Andthe aMCI or AD patients had low level of education (P<0.05).The blood pressure was higher in the patients suffered from aMCI or AD than in people with NCS more or less (P<0.05).The prevalence of aMCI was related to the body mass index (BMI) (P<0.05),while that of AD had no significant relation with BMI (P>0.05).The prevalence of aMCI or AD was not significantly different between male and female or between different birth months.(all P>0.05).Conclusions The prevalence of aMCI increases with age,lower level of education,higher level of blood pressure and BMI,while it has no significant relations with gender or birth month.

Objective To investigate the upper limit of plasma′s alanine aminotransferase (ALT ) donated by volunteers in Chongqing city ,utmost avoid blood discarding due to ALT unqualified and provide a scientific basis for the improvement measures . Methods Checking 115 530 blood donors′ALT by rate method ,the activity of ALT value was normal distribution ,deem x ± 1 .96s as the upper limit of ALT of blood donors ,the upper limit of ALT and the unqualified rate was analyzed according tomonth ,age , gender .Results 95% upper limit of blood donors′ ALT reference range to less than 47 .88 U/L .From June to September ,ALT value unqualified rate compared with other months of the year have significant difference (P<0 .05) .Between different age groups , the upper limit and the unqualified rate had no significant difference(P>0 .05) .There was obvious difference about unqualified rate and upper limit between different sex group ,there was statistical significance (P<0 .05) .Conclusion The quantitative blood agen‐cies should increase propagandist strength ,optimize ALT screening strategy ,gender‐specific blood donors screening measures should be taken ,re‐establish a more scientific ALT Elimination standard ,the maximum reduct blood ALT′s failure rate .To ensure the safety and clinical local blood supply at the same time ,the maximum to avoid waste of blood .

Objective To investigate the effects of lovastatin alone or combined with calcitonin on fracture repair in osteoporotic rats. Methods Forty 4-month-old female SD rats were randomized into 5 groups(8 rats in each group):normal fractured group (A), osteoporotic fractured group (B), lovastatin treatment group(C), calcitonin treatment group (D) and lovastatin combined with calcitonin treatment group. All rats except group A received bilateral ovariectomy. The midshaft femur fracture model was established in all rats 8 weeks after operation. The serum level of procollagen amino-terminal propeptide (PINP) was assessed by ELISA. X-ray and bone mineral density detection was used to observe the fracture healing process. The maximal loading of femoral fractures was analyzed by biomechanical method. Results (1) The serum level of PINP was significantly lower in group A than that of other groups. There was a significantly higher level of PINP in group C and group E than that of group B, and the level of PINP was significantly lower in group D than that of group C. (2) The X-ray showed more progressed fracture healing in group A and group E. The accordingly score indicated that there was a markedly higher score in groups A and group E compared to that of other three groups. (3) There was a highest bone mineral density in the full-length and in the middle of femur bone in group A, followed by group E, group D and group C. The lowest bone mineral density was found in group B. (4) The biomechanical test showed that the maximal loading in femur fracture side was significantly higher in group A than that of other four groups, in which it was higher in group E than that of group B. Conclusion The osteoporosis decreased bone mass and delayed fracture healing process in rat model. The treatment of lovastatin combined with calcitonin showed more positive effect on preventing bone loss and promoting fracture repair than lovastatin alone.

Objective To identify the significance of neuropsychological single-item scales in the diagnosis of mild cognitive impairment (MCI) and Alzheimer's disease (AD).Methods A total of 676 elderly people living around Dongzhimen district in Beijing were recruited using multistage sampling method.Cognitive function was assessed by minimum mental state examination (MMSE)and other scales.MCI was diagnosed based on the criteria proposed by Petersen (1999),and AD was diagnosed based on the NINCDS-ADRDA.Subjects were divided into normal cognitive group (n=213 cases,31.5％),Alzheimer's disease (AD) group (n=167 cases,24.7％),amnestic mild cognitive impairment (aMCI) group (n=186 cases,27.5 ％) and non-AD dementia group (110 cases,16.3 ％).Results The MMSE scores in AD,aMCI and normal groups were 23.0 ± 5.9,25.9±2.6,8.1 ± 1.7,respectively.There were significant differences in MMSE scores between AD,aMCI and NC groups separately (all P＜0.01).Compared with MCI and NC group,th scores of time orientation,attention,calculation and immediate recall and delayed recall were significantly decreased in AD group (all P＜0.01).Comparing with normal group,the scores of attention and calculation were reduced in aMCI group (both P＜0.01).The delayed story recall (DSR) scores in AD,aMCI and NC groups were 15.7 ± 11.7,7.6 ± 4.9,26.5 ± 9.3,respectively.There were significant differences in mean DSR scores between AD,aMCI and NC groups separately (all P＜0.01).Compared with normal group,the clinical dementia rating (CDR) scores were higher and the mean clock drawing task (CDT)scores were lower in AD and aMCI groups (both P＜0.01).Conclusions Both neuropsychological assessment tools such as MMSE and single-item scales such as delayed story recall have the certain significance in the diagnosis of MCI and AD.

OBJECTIVE:To compare the effects of strontium ranelate and PTH(1-34)on bone quality of ovariectomized rats. METHODS:80 SD rats were randomly divided into sham operation group(group A,n=10)and dual ovariectomy(group B,n=70). 3 months after operation,group B were randomly divided into 7 groups,with 10 rats in each group. B0 group were given nor-mal saline [0.9 g/(kg·d)] subcutaneously;B1-B3 groups were given low-dose,medium-dose and high-dose of strontium ranelate [0.45,0.9,1.35 g/(kg·d)] intragastrically;B4-B6 groups were given low-dose,medium-dose and high-dose of PTH(1-34)[30, 60,90 μg/(kg·d),treated for 5 days,rested for 2 days] subcutaneously. Group A was same to group B0 in therapy regimen. All rats were sacrificed 8 weeks later. The contents of P1NP and CTX-1 in serum of rats were determined by ELISA assay;bone densi-ty of 4th lumbar vertebrae was detected by bone densitometer;BV/TV,Tb.Th,Tb.N and Tb.Sp were detected by CT;maximal load and elastic modulus of 5th lumbar vertebrae were measured by compression test. RESULTS:Compared with group A,the se-rum levels of P1NP and CTX-1 in B0-B6 groups increased significantly,while bone density of 4th lumbar vertebrae,maximal load and elastic modulus of 5th lumbar vertebrae decreased significantly in B0-B3 groups(P<0.05);BV/TV level of 4th lumbar verte-brae decreased significantly,while Tb.Sp level increased significantly in B0 group(P<0.05). Compared with B0 group,bone den-sity of 4th lumbar vertebrae,maximal load and elastic modulus of 5th lumbar vertebrae increased significantly in B1-B3 groups (P<0.05);P1NP content,BV/TV,Tb.N level,bone density of 4th lumbar vertebrae,maximal load and elastic modulus of 5th lumbar vertebrae increased significantly in B4-B6 groups,and were higher than in B1-B3 groups(P<0.05). Tb.Sp level of B1-B6 groups decreased significantly and were lower than those of B1-B3 groups(P<0.05). There was no statistical significance in Tb.Th level among 8 groups and CTX-1 content among B0-B6 groups (P>0.05). CONCLUSIONS:PTH(1-34) is better than strontium ranelate in inhibiting bone loss,improving vertebral bone micro-structure and biomechanical properties of ovariectomized rats.

Objective To investigate the preventive effect of Strontium ranelate on stress-absence induced osteoporo?sis in tail-suspended rat. Methods A total of 30 SD rats with average age of 6 month were randomly divided into 3 groups (n=10 in each group):Group A was normal control group while rats in group B and C were subjected to tail suspension test to establish stress absence models. Rats in group C were administered with Strontium ranelate [1 g/(kg·d)]. All rats were sacri?ficed 4 weeks later. Left femurs were harvested for bone mineral density (BMD) test and prepared for undecalcified tissue sec?tion and thereby bone histomorphometry assessment. Bone marrow from right femurs and tibias were cultured and induced to?wards osteogenic-differentiation. The expression levels of osteocalcin in the fourth-passage cultured bone marrow cells and in blood serum were detected separately. Results Rats in group B showed markedly decreased BMD comparing to those in group A and C(P<0.05). Trabecular volume (BV/TV), number (Tb.N) and thickness (Tb.Th) in group B were lower than those in group A and C;erosion percentage (Er.Pm) and osteoclast number (Oc.N) in group B and C were higher than those in group A;comparing to those in group B, bone formation rate (BFR/BV), labeled percentage (L.Pm), were higher in group C, coupled with decreased Er.Pm and Oc.N(P<0.05). mRNA expression levels of OCN in group B and C were higher than those of group A. But its level in plasma were lower in group B than those in group A and C(P<0.05). Conclusion Tail suspension could induce osteosporosis. Strontium ranelate prevent bone loss in stress-absence osteoporosis in rat induced by tail-suspension for 4 weeks, which might be partially through upregulating the expression of OCN, thereby promoting bone formation.

Objective To evaluate the clinical effects of medial patellofemoral ligament reconstruction using the semitendinosus tendon autograft for the treatment of the patellar dislocation.Methods From January 2007 to January 2010,16 cases of patellar dislocation were included in this group.Lysholm score was averaged preoperatively.Arthroscopic-assisted in the semitendinosus tendon autograft reconstruction of the medial patellofemoral ligament,the central graft were fixed on the inner edge of the patellar in the upper 1/3 and the mid-point location,the end were fixed on the channel of femoral epicondyle and adductor tubercle.Results All the patients that lined progressive knee rehabilitation after operation,returned to normal walking for 3 months,6 months could be sports.Followed up for 7-54( 26.36 ± 20.48 ) months,all of patients incision were healed as grade Ⅰ,knee function were normal.Postoperative Lysholm score (93.21 ± 4.68) scores compared with preoperative ( 76.53 ± 8.35 ) scores was significant difference (P ＜ 0.05 ).Conclusions Using the semitendinosus tendon autograft for the treatment of the patellar dislocation method is simple and can effectively restore normal patellar trajectory.At the same time,which is an effective surgical method to treat recurrentdislocation of the patellar.

Objective To investigate the expression of cyclooxygenase-2 (COX-2) and epidermal growth factor receptor (EGFR) in astrecytomas, as well as the correlation between them. Methods The expression of COX-2, EGFR and PCNA were respectively detected by immunohistochmical (S-P) method in 68 astrocytomas and 5 cases normal brain tissue. Proliferation index (PI) was calculated and the correlation of COX-2, EGFR and PI was analyzed. Results COX-2 and EGFR were negative expression in normal brain tissue. The positive expression rate of COX-2 and EGFR in high grade astrocytomas was significantly higher than that in low grade astrocytomas(73.53% vs 44. 18% ,67.65% vs 38.24%, P <0. 01 ), and the PI was significantly higher than that in low grade astrocytumas as well as normal brain tissue(46.11 ± 10. 68vs 23. 04±6. 25,4. 52±0. 95, P <0. 01 ). The PI in COX-2 positive group was higher than that in negative group( P <0. 01 ). The positive expression rate of COX-2 in the group with EGFR positive expression was higher than that in the negative group. Conclusions The expression of COX-2 and EGFR was related to pathological feature of astrocytomas. COX-2 may promote the proliferation of tumor cells. There was a static correlation between the expression of EGFR and COX-2 in astrocytomas. EGFR signal transduction probably modulated the expression of COX-2 in astrocytomas cells.

Objective To establish an indirect immunofluorescence assay for detection of murine norovirus ( MNV) .Methods Mouse leukaemic monocyte macrophage cell line RAW 264.7 cells were infected with MNV-1 and cultured for 36 hours to collect the virus and uninfected cells , and to make antigen glass slides .BALB/c mice were gavaged with MNV-1 (107 TCID50) and infected sera were collected as positive control .The serum was 1:10 diluted and used for measuring MNV antibody by immunofluorescence assay ( IFA ) .80 serum samples were tested using the two methods , IFA and ELISA, and the discrepant samples were validated by Western blotting .Results RAW264.7 cells were infected with MNV-1 for 36-48 h, showing an infection rate of 60% of the cells, and the cells infected for 36 h were preferred.IFA method was used to detect the serum with MNV-1 infection and showed that the antibody content was gradually increased at one week after infection , reaching a maximum antibody concentration at 4 weeks after infection , and maintained a stable level later .The mouse serum at four weeks after MNV-1infection was used as positive quality control . Among the 80 serum samples , 27 positive and 53 negative cases were detected by IFA method , and 32 positive and 48 negative cases were detected by ELISA .The five discrepant samples were verified by Western blotting , resulted in 3 positive and 2 negative cases . The coincidence rate of IFA was 96.0% and that of ELISA methods was 97.5%. Conclusions Basically, immunofluorescence assay can be used to detect the MNV-1 infection in mice, although false negative result may occur occasionally .IFA and ELISA detection can be selected as initial screening measures , and use Western blot assay to verify the discrepant samples .