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 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.

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

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 investigate therapeutic efficacy and mechanisms of action of oncolytic agent derived from herpes simplex virus type 2 (oHSV2) in a xenograft mouse model bearing CT26 colorectal cancer. Methods:BALB/c mice were subcutaneously inoculated with CT26 cells to establish a xenograft mouse model of colorectal cancer. 1) After intratumoral administration of oHSV2, enzyme-linked im-munosorbent assay was used to determine granulocyte-macrophage colony-stimulating factor (GM-CSF) expression levels in the blood. 2) Model mice were divided into three groups:PBS group (negative control), oHSV2 group, and 5-fluorouracil (5-FU) group (positive control). After drug administration, drug effectiveness was evaluated on the basis of weight, tumor volume, general state, and survival time. 3) Cells from the draining lymph nodes (TDLN) and tumor were surgical y removed and used to quantify mature dendritic cel s (DCs) and T lym-phocytes by flow cytometry. Result:1) In the CT26 xenograft model, level of GM-CSF continuously elevated. At day 8, peak value was attained in the blood at concentration of 3150±327.1 pg/mL. Then, GM-CSF expression gradually reduced as time progressed. 2) In in vivo study, both oHSV2 and 5-FU exerted antitumor effects relative to PBS group (50 days vs. 36 days, P<0.01;51 days vs. 36 days, P<0.01), and oHSV2 proved to be less toxic and safer. At day 28, the 5-FU group presented highly significant difference in mouse body weight compared with that of PBS group (16.61 g vs. 22.07 g, P<0.01). However, oHSV2 group did not show statistical y significant change (al P>0.05). Skin of virus injection region did not present necrosis and ulceration. 3) In the TDLN, the frequency of DC was increased when treated with oHSV2 compared with the control group (6.49%vs. 3.73%, P<0.01). Similarly, the percentage of CD4+and CD8+T-cel s from the oHSV2-treated group was signifcantly higher than mock-treated tumors (15%vs. 8.57%, P<0.01;8.19%vs. 5.15%, P<0.01). However, number of cells in the 5-FU group were significantly reduced with respect to that of the negative group (al P<0.01). Conclusion:oHSV2 exerted potent antitumor effects in a murine colorectal cancer model. Compared with 5-FU, oHSV2 treatment caused fewer side effects. Such antitumor effect may be induced by stimulation of immune activity by GM-CSF production.

Objective To investigate the effect of CT guided percutaneous targeted coblation nucleoplasty in treatment of cervical intervetebral disc herniation.Methods Fifty patients who were diagnosed with cervical intervetebral disc herniation by CT or MRI were received the treatment of CT guided percutaneous targeted coblation nucleoplasty and the follow-up check after operation.The effects according to Macnab therapeutic criteria and VAS method were evaluated and recorded before operation and after operation at the third day,2 weeks,3 months.Results All patients accepted follow-up three months after operation.The effects were assessed by Macnab therapeutic criteria:1 9 cases were excellent (37.5%),29 cases good (58.3%),2 cases bad (4.2%),and the effective rate was 92.5%.The VAS scores in three months after operation were significantly lower than that before operation (P <0.05 ). Conclusion Computed tomography guided percutaneous targeted coblation nucleoplasty is a safe,effective and minimally invasive method for treating cervical intervetebral disc herniation.