Objective To make a comparative study on the effects of whole bone marrow culture method and density gradient centrifugation method in isolating hBMSCs. Methods hBMSCs were obtained from healthy adult volunteers and isolated by whole bone marrow culture method and density gradient centrifugation method. Primary cell morphology was observed using inverted phase contrast microscope and the cells in the 2nd passage were stained with HE after being cultured for 7 days. And then, the generation time of the primary, 2nd and 3rd passage hBMSCs was comparedbetween two methods and the surface markers were detected by flow cytometer. In addition, the ALP expression inosteoinductive hBMSCs were evaluated by ALP activity kit at 3, 6 and 9 days and ALP staining was used for osteoinductivehBMSCs with Kaplow method at 9 days. Results Primary cells isolated with whole bone marrow culture method showedaggregation growth while cells isolated with density gradient centrifugation method showed diffusion growth. HE stainingshowed no significant difference in the morphology of the 2nd passage cells between these two methods. The generationtime of primary cells isolated by whole bone marrow culture method (15.36 ± 1.67) days was significantly shorter than that of cells isolated by density gradient centrifugation method [(18.57 ± 1.05) days] (P lt; 0.01), while the generation time of the 2nd and 3rd passage cells showed no statistically significant differences between these methods (P gt; 0.05). The concent of positive surface markers (CD29, CD44, CD71, CD105, CD166) and negative surface marker CD34 in the 2nd cells showed no significant difference between these two isolation methods (P gt; 0.05); however, negative markers CD14 and CD45 showed significant difference (P lt; 0.01). The ALP expression in osteoinductive cells showed no statistical significant (P gt; 0.05) at 3, 6 and 9 days; and the ALP staining positive cell ratio of whole bone marrow culture method was basically in accordance with that of density gradient centrifugation method at 9 days. Conclusion hBMSCs could be isolated by whole bone marrow culture method, and the cell isolation effects of whole bone marrow culture method are equivalent with density gradient centrifugation method.
Objective To investigate the change of vasa vasorum in vessel wall of varicose vein of the lower extre-mity. Methods Thirty-two patients with varicose vein of the lower extremity were collected， in which of 12 patients with simple varicose veins （varicose group）， 9 patients with recurrent varicose veins （recurrent group）， 11 patients withthrombophlebitis of varicose vein （thrombophlebitis group）， 9 patients with normal venous tissue as control group. HE staining was performed to observe the distribution of vasa vasorum and detect the vasa vasorum density. Results The increasing vasa vasorums were observed in the adventitia and media， but few was observed in the intima in the varicose， recurrent， and thrombophlebitis groups. The distribution of vasa vasorum was in the adventitia in the control group. The vasa vasorum densities （/mm2） in the varicose， recurrent， and thrombophlebitis groups （5.65±1.45，6.20±1.73， and 5.94±1.63， respectively） were greater than those in the control group （2.87±0.54）， the difference wasstatistically significant （P＜0.05）， but there was no significant difference of the vasa vasorum density among the varicosevein， recurrent， and thrombophlebitis groups （P＞0.05）. Conclusion Change of vasa vasorum is an important pathol-gical change with the nosogenis of varicose vein of the lower extremity.
The rapid development of high-throughput chromatin conformation capture (Hi-C) technology provides rich genomic interaction data between chromosomal loci for chromatin structure analysis. However, existing methods for identifying topologically associated domains (TADs) based on Hi-C data suffer from low accuracy and sensitivity to parameters. In this context, a TAD identification method based on spatial density clustering was designed and implemented in this paper. The method preprocessed the raw Hi-C data to obtain normalized Hi-C contact matrix data. Then, it computed the distance matrix between loci, generated a reachability graph based on the core distance and reachability distance of loci, and extracted clustering clusters. Finally, it extracted TAD boundaries based on clustering results. This method could identify TAD structures with higher coherence, and TAD boundaries were enriched with more ChIP-seq factors. Experimental results demonstrate that our method has advantages such as higher accuracy and practical significance in TAD identification.