BACKGROUND: Most reported biomechanical studies on sacroiliac joint injury and fixation use cadavers or artificial bone models to simulate the sacroiliac joint injury.OBJECTIVE: To analyze the vertical stability of anterior plate fixation for sacroiliac joint dislocation using three-dimensional finite element method. METHODS: The anterior plate fixation model of unilateral sacroiliac joint dislocation was constructed on the basis of the three-dimensional finite element model of a complete pelvis. An axial load of 500 N was applied on the model; the cloud pictures of stress, strain and displacement were obtained after calculation and compared with that of the complete pelvis under the same conditions.RESULTS AND CONCLUSION: Stress concentration occurred at the internal fixation system; the maximum stress was found at the screws near the injured sacroiliac joint, far greater than the maximum stress of the complete pelvis under the same condition. The maximum strain was found in the healthy sacroiliac joint; the fixed sacroiliac joint had no strain. The maximum displacement was found in the injured sacroiliac joint; it was about twice longer than the complete pelvis. These findings indicate that the vertical stability of pelvis is poor using anterior plate internal fixation treatment for sacroiliac joint dislocation; and stress concentration occurs at the screws and plates.

Objective To evaluate the availability and sensitivity of MR whole body diffusion weighted imaging (DWI) in searching primary tumors in patients with metastases.Methods Thirty-four patients with symptoms of metastases and unknown primary leasions were scanned by whole body DWI.All the metastases cases were diagnosed by CT,single photon emission computed tomography(SPECT) or MRL For the cases of suspected primary tumors,apparent diffusion coefficient (ADC) values of the primary and metastatic lesions were measured respectively.For the cases with primary lung cancers and metastases proved by pathology of biopsy or surgical specimens,statistics analysis of ADC values of primary and metastatic lesions was performed with paired samples t-test.The detection rate and sensitivity of this technique for screening primary tumors were evaluated.Results By whole body DWI,24 cases were found with suspected primary lesions,in which 23 cases were proved primary tumors,and 1 case was proved benign lesion.Ten cases were not identified with primary lesions on whole body DWI,but in which 2 cases were proved primary malignant tumor by biopsy later,and the other 8 cases remained unknown within follow-up of half a year to one year.For the 14 definite cases of lung cancers,the average ADC values of primary and metastatic lesions was (1.24±0.18)×10-3 and(1.16±0.27)×10-3mm2/s,respectively (t=1.28,P>0.05).The detection rate and sensitivity of whole body DWI for searching primary tumors was 67.6% (23/34) and 92.0% (23/25),respectively.Conclusion The sensitivity of whole body DWI for searching primary tumors is relatively high,and it can be used to search primary tumors in patients with metastases.

OBJECTIVETo observe the effect of sodium tanshinone II (A) sulfonate (STS) on Ang II -induced atrial fibroblast collagen synthesis and TGF-beta1 activation.

METHODAtrial fibroblasts of neonatal rats were cultured to determine the content of collagen protein. The original synthesis rate determined by the [3H]-proline incorporation method was taken as the index for myocardial fibrosis. The content of active TGF-beta1 and total TGF-beta1 in cell culture supernatants were tested and cultured by ELISA. The expression of thrombospondin-1 (TSP-1) was assessed by using Western blot.

RESULTAng II could significantly increase the content of atrial fibroblast collagen and the collagen synthesis rate, the TSP-1 expression and the concentration of active TGF-beta1, without any obvious change in total TGF-beta1. After the STS treatment, all of the indexes, apart from total TGF-beta1, were obviously down-regulated.

CONCLUSIONSTS could decrease the secretion of Ang II -induced atrial fibroblast collagen and the synthesis rate. Its mechanism is related to the inhibition of TSP-1/TGF-beta1 pathway.

Angiotensin II ; pharmacology ; Animals ; Collagen ; biosynthesis ; Fibroblasts ; cytology ; drug effects ; metabolism ; Gene Expression Regulation ; drug effects ; Heart Atria ; cytology ; Phenanthrenes ; pharmacology ; Rats ; Rats, Wistar ; Signal Transduction ; drug effects ; Thrombospondin 1 ; metabolism ; Transforming Growth Factor beta1 ; metabolism

Animals ; Carotid Arteries ; surgery ; Carotid Artery Injuries ; etiology ; Disease Models, Animal ; Female ; Mice ; Mice, Inbred C57BL ; Microsurgery ; Random Allocation

Adult ; Combined Modality Therapy ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Humans ; Infectious Disease Transmission, Patient-to-Professional ; Male ; Medicine, Chinese Traditional ; Middle Aged ; Phytotherapy ; Severe Acute Respiratory Syndrome ; therapy

Objective To study the difference of image quality and radiation dose between different exposure modes with full-field digital mammography (FFDM).Methods The Fluke18-220mammographic phantom was exposed by FFDM system with different exposure modes at automatic exposure control ( AEC ) ,including contrast mode,standard mode and dose mode,and the exposure factors and radiation dose were recorded.The images on monitor with the best window width and window level were read by four independent radiologists.The images of specks groups,nylon fibers and masses was assessed by the four experienced readers at the criterion of American College of Radiology.Results The detection of specks groups,nylon fibers and masses were statistically different at the contrast mode and standard mode (F =41.321,P ＜ 0.05),further at the contrast mode and dose mode.The detection of specks groups、nylon fibers and masses were not statistically different( P ＞ 0.05 ) at standard mode and dose mode,but the radiation doses were different.The ESD at standard mode and dose mode was 4.5 and 3.15 mGy,respectively.The AGD of standard mode and dose mode was 1.18 mGy and 0.78 mGy,respectively.Conclusions The standard mode and dose mode of FFDM might be fit for most patients,especially at the dose mode.Contrast mode of FFDM should be strictly controled in use.

AIM:To investigate the effects of pioglitazone on the quantity and function-related factors of regu-latory and effector T cells ( Treg and Teff ) of uremic apolipoprotein E knockout mice in vitro with or without the stimulation of atherosclerotic plaque-specific antigen oxidized low-density lipoprotein ( oxLDL) .METHODS:Uremic apolipoprotein E knockout mouse model was established by 2-step surgical procedure.After intervention with different concentrations ( 2μmol/L and 20μmol/L) of pioglitazone and PPARγantagonist GW9662 (5μmol/L) on splenocytes of uremic mice for 12 h in the presence or absence of oxLDL (2 mg/L), the levels of CD4 +CD25 +Foxp3 +Treg and IFNγ+CD4 +Teff were de-termined by flow cytometry.The mRNA expressions of Foxp3 and IFNγwas detected by real-time fluorescent quantitative PCR.RESULTS:In vitro, oxLDL induced a Treg/Teff imbalance in splenocytes from the uremic mice.Pioglitazone up-regulated the level of Treg and mRNA expression of Foxp3 in the presence of oxLDL, which was not antagonized by GW9662.Meanwhile, pioglitazone downregulated the level of Teff and mRNA expression of IFNγin the presence or ab-sence of oxLDL, which was reversed by GW9662.CONCLUSION:oxLDL induces a Treg/Teff imbalance in uremic apo-lipoprotein E knockout mice.Pioglitazone modulates the Treg/Teff imbalance probably through PPARγ-independent and-dependent mechanisms.

AIM: To analyze the effect of pigment epithelium derived factor (PEDF) on nitrogen monoxide (NO) and expression of cysteine-containing, aspartate-specific proteases-3 (caspase-3) in retinal tissues of model rats with optic nerve crush injury.METHODS: A total of 60 SD rats were randomly divided into the blank control group, model group and PEDF group, with 20 rats in each group.Except the blank control group, the optic nerve crush injury rat models were established in the other groups, and left eyeballs were taken as samples.After successfully modeling, the model group were treated with intravitreal injection of 5μL of balanced salt solution while PEDF group were treated with intravitreal injection of 5μL of PEDF (0.2μg/μL).Two weeks later, the retinal tissues were collected, and changes of shape were observed under microscope after HE staining.The changes of NO level were measured by colorimetry assay, the expression of caspase-3 mRNA and caspase-3 protein was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western-blot.RESULTS: HE staining showed that retinal tissues of the blank control group arranged neatly and clearly.Retinal ganglion cells (RGCs) arranged in a monolayer, and cells were oval, uniform in size and distribution, the cell nuclei were clear, closely arranged, with clear boundaries.The retinal tissues of the model group were sparse in shape, RGCs showed vacuolar changes, the overall number of cells was reduced, and cell nuclei of residual RGCs showed pyknosis and uneven staining.RGCs in PEDF group were with slightly edema and arranged closely, and the degree of injury was significantly milder than that in the model group.Levels of Caspase-3 mRNA and protein and NO levels in the three groups showed the model group > PEDF group > blank control group (all P < 0.05).CONCLUSION: The application of PEDF can down regulate the expression of Caspase-3 and NO in rates with optic nerve injury and reduce RGCs injury.

Objective To observe the clinic efficacy of open transforaminal lumbar interbody fusion (TLIF) compared with minimally invasive operation in treating lumbar spinal stenosis and instability among obese and non‐obese patients .Methods A ret‐rospective analysis was performed in these cases of mono‐segmental lumbar spinal stenosis and instability between January 2011 and January 2013 .Perioperative index ,clinical efficacy ,and imaging results were observed and compared between different groups .Re‐sults Thirty‐four obese cases and 105 non‐obese cases were divided into two groups ,including conventional posterior open TLIF and minimally invasive TLIF operation ,to compare the results .Perioperative indexes of obese patients were more than non‐obese patients undergone open TLIF operation way and there was significant difference(P<0 .01);while by minimally invasiveTLIF oper‐ation way ,comparing the results of the surgical blood loss and incision size between obese and non‐obese group ,there was signifi‐cant difference(P<0 .05) .However ,there was not significant difference in the operative time between two groups(P>0 .05) .No cases of slippage or breakage of implants were found among all these patients after 6 months of follow up .Postoperative VAS and ODI among these four groups were better than before(P<0 .01) .Undergoing open postoperative VAS in obese group and in non‐obese group ,there was significant difference(P< 0 .05);undergoing minimally invasive postoperative ODI in obese group and in non‐obese group ,there was significant difference(P< 0 .05) .But ,undergoing open postoperative ODI in obese group and in non‐obese group ,there was not significant difference(P>0 .05);undergoing minimally invasive postoperative VAS in obese group and in non‐obese group ,there was not significant difference(P>0 .05) .Conclusion Therefore ,obese may be risk factor in treating lumbar spinal stenosis and instability .

Aim To observe mesenchymal stem cell differentiation into osteoblast induced by TSPG, and explore how TSPG enhances the promotion of hemato-poiesis of osteoblast differentiation from mesenchymal stem cell. Methods MSCs were cultured by TSPG combined with osteoinductive medium. The cellular vi-ability of proliferation was detected with MTT assay. The content of alkaline phosphatase in the cultural su-pernatant was tested with pNPP assay. The ability of MSCs to form calcium nodes was also observed after a-lizarin red stain. The protein expression of RUNX2 was analyzed with Western blot. The content of cytokines associated with hematopoiesis was tested with Elisa as-say. The ability of promoting hematopoiesis was detec-ted with hematopoietic colony forming assay. Results Both MTT and pNPP assay showed that optical den-sity ( OD) values were increased in response to TSPG treatment in a dose-dependent manner. The mineraliza-tion formation ability was enhanced with TSPG-treat-ment. Meanwhile, the expression of RUNX2 protein was up-regulated in TSPG-treated cell. Moreover, the content of cytokines associated with hematopoiesis and the number of hematopoietic progenitor colony were in-creased by TSPG-treatment compared with the control group. Conclusion TSPG could induce MSCs differ-entiation in to osteoblast and enhance the effect of oste-oblast differentiation from MSCs on promoting hemato-poiesis.