BACKGROUND:The design of proximal femoral locking compression plate existed defects. Therefore, our team designed triangle truss locking plate with hyper-short arm according to proximal femoral locking compression plate (patent No. 201220051751.2).
OBJECTIVE:To design and make triangle truss locking plate and evaluate its biomechanical properties.
METHODS:Triangle truss locking plate with hyper-short arm was designed based on the support of two proximal screws of proximal femoral locking compression plate. Five pairs of fresh adult femur specimens were prepared, and the model of A3.1 (AO classification) reverse intertrochanteric fracture was established. Experimental group (right side) was fixed with triangle truss locking plate. Control group (left side) was fixed with proximal femoral locking compression plate. Stress distribution of the screws of proximal end of the plate, stress distribution of the fracture ends, the opening angle of fracture, and maximum load were detected.
RESULTS AND CONCLUSION:(1) Stress distribution of the four screws of the proximal femoral locking compression plate was average in the experimental group, and the stress distribution of the two screws of triangle truss locking plate was close. Stress distribution of the four screws was not average in the control group. The proximal screw bearing stress was bigger in the control group than in the experimental group (P < 0.05). (2) Open angle under different loads were significantly smaler in the experimental group than in the control group (P < 0.05). (3) Maximum load was higher in the experimental group than in the control group (P < 0.05). Moreover, the position of damage was different between the two groups. The fixation in the experimental group was reasonable. These findings suggest that various biomechanic properties of the triangle truss locking plate with hyper-short arm were better than that of proximal femoral locking compression plate. Its fixation was reliable. Triangle truss locking plate could effectively reduce or avoid breakage of the plate and screw or coxa vara.

Objective: To observe the interface bonding between the coral and new bone. Methods: The block coral was implanted on rabbit calvaria subperiosteally. The specimens were observed by the scanning electron microscopy 2, 4, 8, 12 weeks after operation respectively. Results: The coral was progressively absorbed and replaced by new bone. The coral bond to bone directly. No intervening layer was found between coral and bone. Conclusion: The coral bond to bone by direct mechanical way. [

[Objective]To analyze the causes of perioperative periprothetic fracture with hip arthroplasty and discuss the prevention and treatment of the fracture.[Method]18 of 640 THR cases occurred femoral fracture from July 1995 to August 2006,11 with intraoperative fracture and 7 with postoperative fracture,12 were and 6 female,the mean age 68 years(range:51 to 79 years).According to AAOS'standard,18 cases were divided into 6 types:1 of I type,6 of II type,4 of III type,4 of IVa type,2 of IVb type,1 of V type and 2 of VI type.10 of 11 cases of intraoprative fracture were operated immediately with internal fixation,and one of II type was treated with conservative method.4 of 7 cases of postoperative fracture were operated with open reduction and internal fixation in two weeks,2 cases with loosen stem were operated by revision hip,and one of V type was treated with conservative method because of other disease.[Result]The mean followed up perioid were 15.2 months(rang:6 to 42 months),15 fractures united,2 delayed united and 1 dead after 8 months postoperatively.The average scores were 80 according to Harris'standard(range:67 to 92).[Conclusion]Violence、abnormal of femur cannal、osteoprosis and bigger prothesis are the main causes of intraoperatively peri-prothetic femur fracture after THA,and loosening、 osteoperosis and outside injury are the main causes of postoperatively periprothetic femoral fracture,different treatment should be used according to the different types.

[Objective]To study the reason of loosening prothesis by observing the interface membranes harvested during the hip revision operation.[Method]Thirty eight specimens of interface membranes around the loosening prothesis were harvested from thirty eight patients who underwent the revision of total hip replacement.All the specimens were underwent outer observation,light and scanning electronic microscopic observation.[Result]All the gap of the loosening prothesis were filled with interface membranes with different thickness.A large number of the foreign pelletand bone pieces were found under scanning electronic microscope.[Conclusion]Interface membranes growed and filled in the gap between the loosening prothesis and bone(or bone cement).The wear debris stimulated the interface membrane to release bone resorption factors which caused the prothesis loosening,and the more loosening,the more large gap appeared,and the more resorption factors released from the interface membranes due to the debris stimulating,which formed vicious circle.Cutting the link of the circle could decrease the loosening rates.

Objective: To develop and optimize a self-microemulsifying drug delivery system (SMEDDS) formula for improving the dissolution of atorvastatin calcium.Methods: Solubility and pseudo-ternary phase diagram were used to select the suitable type and amount range of oil phase, surfactant and co-surfactant.D-optimal mixture design was used to optimize the formula of atorvastatin calcium SMEDDS.The morphology, particle size distribution and zeta potential of the microemulsion were determined by a dilution method.The in vitro drug release profiles of the marketed atorvastatin calcium tablets and the self-made SMEDDS were compared.Results: The formula of atorvastatin calcium SMEDDS was as follows: Capmul MCM as the oil phase, Labrasol as the surfactant and Transcutol P as the co-surfactant with the optimal weight ratio of 13.0∶43.5∶43.5.The self-made SMEDDS was a clear and transparent microemulsion solution with homogeneous small spheres as seen under a transmission electron microscope.The particle size, PdI and zeta potential of the self-made SMEDDS was (34.2±13.6) nm, (0.169±0.04) and (-21.1±1.3) mV, respectively.The in vitro release profile indicated that the accumulated release of the self-made SNEDDS reached up to nearly 100% in 45 min.Conclusion: The optimal formula of atorvastatin calcium SMEDDS optimized by D-optimal mixture design can improve the drug dissolution rate effectively.

BACKGROUND:Some studies have showed that the accuracy and surgery outcome of the percutaneous pedicle screw implantation was superior to open surgery, but the relationship between the angle of pedicle screws and screw stability is stil unclear in previous studies. OBJECTIVE:To investigate the effect of different angles of implanted screws on the stability of pedicle screw. METHODS:A total of 30 vertebral specimens of adult pigs were selected and screws were implanted respectively according to different coronal and sagittal angles. The maximum pul-out strength of screws from each specimen was tested by machine. Load-displacement curves were drew and statistical y analyzed. RESULTS AND CONCLUSION:The maximum pul-out strength and maximum energy of screw with 10° and 15° coronal and sagittal angles implantation were significantly better than those of 0° angle group (P<0.05). When the stress exceeded the maximum pul-out strength, the pul-out strength of screw decreased gradual y. The curves in coronal and sagittal 10° and 15° angle groups was similar, and the slope was better than 0° angle group (P<0.05). These results confirm that the angle of the implanted screw provides effective assistance to the stability of percutaneous pedicle screw. After the looseness of the screws, the pul out strength shows a steady downward trend.

Objective To explore the relationship between serum cardiac troponin I (cTnI) and high sensitivity C-reactive protein (hs-CRP),tumor necrosis factor-alpha (TNF-α ) in patients with acute organophosphorus pesticide poisoning (AOPP) and their clinical significance.Methods One hundred and twelve patients with AOPP (without sudden death ) were as AOPP group.One hundred and twelve healthy controls were as control group.Serum cTnI,hs-CRP and TNF-α levels were determined by ELISA and compared between two groups.The relationship between serum cTnI and hs-CRP,TNF-α was analyzed.Time for atropinization and acetylcholinesterase activity recovery and days of hospitalization were observed.The effectiveness of AOPP patients in different serum cTnI levels was compared.Results Serum cTnI,hs-CRP and TNF- α levels in AOPP group[0.75 (0.26,0.99) μ g/L,11.57(5.13,21.62) mg/L,( 12.36 ±5.22) μ g/L] were higher than those in control group[0.01 (0,0.03) μ g/L,3.62(2.31,6.80) mg/L,(7.33 ±4.31 ) μ g/L] (P ＜ 0.01 ).Serum cTnI levels were positive correlation with serum hs-CRP and TNF- α levels in AOPP patients (r =0.53,0.62,P ＜ 0.01 ).Time for atropinization and acetylcholinesterase activity recovery and days of hospitalization in higher serum cTnI levels patients ( 56 cases ) [(7.31 ± 1.96),( 15.29 ± 3.66 ),(17.23 ± 3.62) d] was longer than that in lower serum cTnI levels patients (56 cases)[(5.32 ± 1.03),( 11.32 ± 2.59),( 13.66 ± 3.03) d](P＜ 0.01).Conclusions Cardiac insults in AOPP patients are related to inflammation.Sudden death-free AOPP patients with higher cTnI levels have less response to treatments.

The clinical thought is the core and the foundation of clinical ability.The logical teaching strengthens the students'clinical thought most directly and effectively.Through the thought training,the inference thought training and the basic thought rule training the medical students' clinical thought ability can be effectively strengthened.

Objective To identify and investigate B(A)02 allele in a patient. Methods Serological tests were performed with standard serological methods in a patient with B(A)02 allele. DNA sequences of all seven exons and exon-intron boundaries of ABO gene were analyzed by polymerase chain reaction (PCR), direct DNA sequencing and sequencing after gene cloning. In order to analyze the allele, PyMOL software was used to establish 3D model of Glycosyltransferases B (GTB). Results The serological results showed the characteristics of B(A) phenotype. DNA analysis revealed that ABO gene of the individual was heterozygous of B(A)02/O01 allele. 700C>G mutation was identified in B101 allele, which resulted in the amino acid substitution P234A in GTB. Through the analysis of the 3D structure of GTB, it was speculated that the P234A replacement affected the intermolecular forces of the 234 amino acid and Met-266, thus changed the conformation of the donor-binding pocket of GTB,that made GTB capable of recognizing and tranferring the GalNac to the H antigen, which can lead to the formation of the weak A antigen on membrane of red blood cells. Conclusion The P234A replacement can affect the spatial conformation of the specific recognition region conformed by Met-266 and Ala-268 residues, which leads to the antigenicity change of the ABO blood group.

Background As a main cellular component of retinal microvascular,retinal vascular endothelial cells (RVECs) play critical roles in the occurrence and development of diabetic retinopathy (DR) by proliferating,migrating and angiogenesis.Apolipoprotein A-Ⅰ (ApoA-Ⅰ) is the major apolipoprotein of high density lipoprotein.ApoA-Ⅰ is overexpressed in the retina of diabetic patients and plays different effects on RVECs upon different microenvironments,but its relationship with RVECs in high glucose environment is still not elucidated.Objective This study was to investigate the effects of ApoA-Ⅰ on proliferation,migration,tubulogenesis and vascular endothelial growth factor (VEGF) expression in human RVECs (hRVECs) in high glucose environment.Methods hRVECs were cultured with DMEM containing 10％ fetal bovine serum and passaged,and the cells at generation 3 to 6 were used in the study.The cells were divided into low-glucose group,low-glucose+ApoA-Ⅰ group,high-glucose group and high-glucose+ApoA-Ⅰ group,and the low concentration glucose (5 mmol/L),high contration glucose (25 mmol/L)and ApoA-Ⅰ (30 μg/ml) was added separately according to grouping.The proliferation and migration rate of the cells were evaluated by cell counting kit-8 (CCK-8) assay and scratch wound test respectively.The tubulogenesis of the cells was examined by tube formation test.The mRNA and protein expression of VEGF in the cells was detected by using real-time fluorescence quantitative PCR and Western blot.Results The prolifative value (absorbancy) and migration rate of the cells in the high-glucose group were significantly higher than those in the low-glucose group,and those in the high-glucose+ApoA-Ⅰ group were significantly reduced in comparion with the high-glucose group (A value:P =0.001,0.033;migration rate:P =0.001,0.010).The number of tubes in the low-glucose group,low-glucose+ ApoA-Ⅰ group,high-glucose group and high-glucose+ApoA-Ⅰ group was 7.250±2.217,9.250±2.630,19.000± 3.916 and 11.500±3.697,showing a significant difference among the groups (F=10.335,P=0.001).The number of tubes in the high-glucose group was more than that in the low-glucose group,and the number of tubes in the highglucose+ApoA-Ⅰ group was less that that in the high-glucose group (P=0.001,0.037).The relative expression levels of VEGF mRNA were 0.944 ± 0.083,1.117 ± 0.204,1.768 ± 0.164 and 1.301 ± 0.077,and those of V EGF protein were 1.000±0.130,1.217±0.152,1.871 ±0.101 and 1.609±0.087 in the low-glucose group,low-glucose+ ApoA-Ⅰ group,high-glucose group and high-glucose+ApoA-Ⅰ group,respectively,with significant differences among the groups (mRNA:F =18.640,P =0.001;protein:F =10.335,P =0.001),and the expressions of VEGF mRNA and protein in the high-glucose group were significantly higher than those in the low-glucose group and high glucose+ ApoA-Ⅰ group (mRNA:P=0.000,0.004;protein:P=0.000,0.029).Conclusions ApoA-Ⅰ plays inhibitory effects on the proliferation,migration and tubulogenesis of hRVECs in high glucose environment,which may be associated with the downregulation of VEGF expression.