Objective:To eveluate and study the anatomic basis of the posterior contour sign of lumbar intervertebral disc.Methods:The most protruding length of the soft tissue mass behind intervertebral spase on lumbar plain film were measured in 100 cases and compared with CT or MR findings.Results:41 posterior contour sign of the interlumbar disc were fined in 39 cases,of which there were 25 in L4/5(61.0%),15 in L3/4(15.6%)and 1 in L2/3(2.4%).The protruding was less than 0.2 cm in 26 and larger than 0.2 cm in 15,there were 10 lumbar disc protruding confirmed by CT or MR ,7 of which the pesterior contour ≥0.2 cm,and 3＞0.3 cm,none was ≤0.2 cm.Conclusion:The adipose tissue in the posterior border of lumbar body and disc was the anatomic basis of the sign,and it was an importent sign for diagnosing of lumbar disc hernia on plain film.

Objective To observe the effects of pretreatment with dimethyloxalylglycine (DMOG) on the survival of multi-territory perforator flap and the vessels of choke zone (CZ) 2 in rat,and to explore related mechanism.Methods Sixty adult SD rats were divided into group DMOG and normal saline group (NS) according to the random number table,with 30 rats in each group.Perforator flap with three angiosomes was made on the right dorsal side of rat,including deep iliac circumflex artery perforator,intercostal artery perforator,thoracodorsal artery perforator,as well as CZ 1 and CZ 2.Rats in group DMOG were intraperitoneally injected with 2 mL NS containing DMOG (40 mg/kg) 2 days before operation,2 hours before operation,and 2 days after operation.Rats in group NS were intraperitoneally injected with equivalent volume of NS at the same time point.On post operation day (POD) 7,gross observation was conducted,and the survival rate of flap was calculated.On POD 7,the vascularity in CZ 2 and potential zone of flap was observed using angiography.On POD 7,new vessel in CZ 2 of flap was observed with HE staining,and the microvessel density (MVD) was calculated.On POD 7,the expression of vascular endothelial growth factor (VEGF) in CZ 2 of flap was detected by immunohistochemistry and Western blotting (respectively denoted as integral absorbance values and ratio of gray value),and blood flow volume of vessel in CZ 2 of flap was examined by laser Doppler perfusion imager.The sample number of each index was 6 in each group.Data were processed with t test.Results (1) On POD 7,rats in two groups all survived,and the flaps were not infected.In group DMOG,the necrotic area of flaps of rats with dark yellow crust and soft texture was observed approximately at the distal end of skin entry point of thoracodorsal artery perforator.In group NS,the necrotic area of flaps of rats with brownish black crust and hard texture was observed approximately at the distal end of CZ 2.The survival rate of flap of rats in group DMOG was (88 ± 3) ％,which was significantly higher than that in group NS [(82 ± 3) ％,t =3.38,P ＜ 0.01].(2) On POD 7,there were clear vascular structure and many new vessels in CZ 2 of flaps of rats in group DMOG,with intact vascular structure in potential zone.On POD 7,there were unclear vascular structure and few new vessels in CZ 2 of flaps of rats in group NS,with disorder vascular structure in potential zone.(3) On POD 7,MVD in CZ 2 of flaps in rats of group DMOG was (29.2 ± 2.2)/mm2,which was significantly higher than that of group NS [(20.3 ± 3.6)/mm2,t =5.10,P ＜0.01].(4) On POD 7,the expressions of VEGF in CZ2 of flaps in rats of group DMOG detected by immunohistochemistry and Western blotting were 5 060 ± 432 and 0.48 ± 0.04 respectively,which were significantly higher than those of group NS (2 811 ± 382 and 0.26 ± 0.06,with t values respectively 9.54 and 5.67,P values below 0.01).(5) On POD 7,blood flow volume of vessel in CZ 2 of flaps in rats of group DMOG was (58 ±4) perfusion units (PU),which was significantly more than that of group NS [(46 ± 4) PU,t =5.20,P ＜ 0.01].Conclusions DMOG can increase the survival rate of multi-territory perforator flap through promoting angiogenesis in CZ 2 of flap on the back of rat and improving blood supply of flap.

Objective : To explore the molecular mechanisms of immunosuppressive activity of soluble CD83 (sCD83) . Methods : Bone marrow⁃derived dendritic cells ( DCs) and CD4 + T cells in the spleen were isolated from bone marrow progenitor cells of 6 - 8 ⁃week⁃old C57B/6 mice. DCs and CD4 + T cells were treated with 10 μl PBS (Control group) or 10 μl 10 μg/ml soluble CD83 (sCD83 group) , respectively. Immature DCs (imDCs) in DCs and CD4 + CD25 + FOXP3 + T cells (Treg cells) in CD4 + T cells were determined by flow cytometry. Western blot was used to determine the expression levels of indoleamine 2 ,3 ⁃dioxygenase (IDO) in imDCs and the expression levels of phosphatase and tensin homolog (PTEN) , phosphorylated⁃Akt serine/threonine kinase 1 ( p⁃Akt) , Akt , nucleus NF⁃κB subunit (RelB) , cytoplasm RelB and programmed cell death 1 ( PD⁃1) in Treg cells. ELISA was used to determine the level of kynurenine in DCs culture supernatant , and the levels of interleukin⁃10 ( IL⁃10) , transforming growth factor⁃β (TGF⁃ β) and IL⁃12 in imDCs and CD4 + T cells co⁃culture system. Results: Compared with Control group , the percentage of DCs cell counts expressing the surface markers of CD40 , CD83 , CD86 and major histocompatibility complex class⁃ Ⅱ (MHC Ⅱ ) in sCD83 group decreased (P < 0. 05) , with the level of kynurenine in DCs culture supernatant increased (P < 0. 05) . Compared with Control group , the percentage of Treg cell counts in sCD83 group increased ( P < 0. 05) , with the expression levels of PTEN and cytoplasm RelB enhanced (P < 0. 05) , while the expression levels of p⁃Akt , nucleus RelB and PD⁃1 decreased (P < 0. 05) . There was no significant difference in the expression level of Akt between the two groups. In the imDCs and CD4 +T cells co⁃cultured supernatants , compared with Control group , the levels of IL⁃10 and TGF⁃ β increased , and the level of IL⁃12 decreased in sCD83 group (P < 0. 05) . Conclusion sCD83 can inhibit CD4 + T cells nucleus RelB levels and regulate cytokines secretion so as to have an effects on cellular crosstalk of imDCs and Treg cells and promote imDCs and Treg cells proliferation.