[Safety and efficacy of a new domestic distal perforated stent graft in the treatment of Stanford type B aortic dissection].

Objective: To evaluate the safety and efficacy of a new domestic distal perforated stent graft (Talos stent) in the treatment of Stanford type B aortic dissection (TBAD). Methods: Twenty-five patients with TBAD treated with Talos stent in Yan'an Hospital Affiliated to Kunming Medical University from February 2018 to December 2019 were selected as the research subjects. Intraoperative angiography was performed to determine the number of branch arteries that remained after stent release. On postoperative day 5 (POD5), the pain intensity of the patients was evaluated by visual analog scale (VAS). The computed tomography angiography (CTA) of the patients before operation, 6 months and 12 months after operation were compared including aortic diameter, true lumen diameter, and false lumen diameter at the level of tracheal bifurcation. Follow-up was performed 1 month, 6 months, 12 months, and 24 months after surgery, and the occurrence of stent-related adverse events, reoperation and survival rate were recorded. Results: The enrolled patients included 19 males and 6 females, aged (52.6±11.1) years. Intraoperative angiography showed that 4 (1, 7) branch arteries were preserved, and the VAS score was 1 (0, 1) on POD5. The aortic diameters at the level of the tracheal bifurcation were (34.9±1.1) mm, (34.6±0.9) mm and (34.8±1.0) mm before surgery, 6 months and 12 months after surgery, and there was no significant difference (P=0.926); the diameters of the main true lumen at the level of the tracheal bifurcation were (13.3±1.6) mm, (21.8±1.0) mm and (22.3±1.1) mm before surgery, 6 months and 12 months postoperatively, while the diameters of the main false lumen at the level of the tracheal bifurcation were (20.8±2.2) mm, (4.5±1.5) mm, and (4.6±1.7) mm, respectively. Compared with before surgery, the diameter of true lumen increased significantly 6 months and 12 months after surgery (both P<0.001), while the diameter of false lumen decreased (both P<0.001). No stent-related adverse events occurred within 30 days after surgery, no secondary operations occurred within 12 months after surgery, no type Ⅰ and type Ⅲ endoleaks, no deaths or cases of paraplegia were reported, and the stent structure and position remained good. There were no deaths or paraplegia cases 24 months postoperatively, and no stent-related adverse events occurred. Conclusion: Using Talos stent in the treatment of TBAD can effectively help remodel the aorta, while preserve the intercostal artery and spinal artery, with good clinical effect and safety.

High resolution bands in maize chromosomes by G-banding methods.

It was demonstrated that G-bands are unequivocally present in plant chromosomes, in contrast to what had been formerly believed by plant cytologists. Maize chromosomes prepared by an enzymatic maceration method and treated with trypsin or SDS showed clear G-bands spreading along the chromosomes. The most critical point during the G-banding procedures was the post-fixation with glutaraldehyde solution. Banding patterns were processed by using the chromosome image analyzing system and a clearer image was obtained. Gbanding technique and the image manipulation method described here can be applied to many plant species, and would contribute new information in the field of plant cytology and genetics.