The supercondensed DNA, a special kind of topological structure of plasmid DNA, was firstly found in E. coli SD108(topA+ gyrB225). Now, this structure is also found in E. coli DM800(topA- gyrB225). The result indicates that the formation of supercondensed DNA is related with decrease of the activity of gyrase in vivo. Topoisomerase Ⅳ was proved to relax the supercondensed DNA completely in vitro, which suggested that the supercondensed DNA and the supercoiled DNA could transform to each other in cells. The supercondensed DNA samples were analyzed by atomic force microscopy and compared to supercoiled DNA. The results showed that the length of supercondensed DNA decreased about 30% and the width and height of double-strand increased about 60%, which indicates that the structure of double-strand of supercondensed DNA is much more similar to A-DNA than B-DNA. The results also showed that chloroquine intercalation did not change the supercoiling level of supercondensed DNA, but made it knot and compact.

Objective:To investigate the short-term outcomes of robot-assisted pancreato-duodenectomy (RPD) performed by one single surgeon.Methods:The retrospective and descriptive study was conducted. The clinico-pathological data of 240 patients who were performed RPD by one single surgeon at The First Affiliated Hospital of Sun Yat-sen University from July 2016 to October 2023 were collected. There were 130 males and 110 females, aged 59(19)years. All RPD were performed by the same surgeon. Observation indicators: (1) surgical situations; (2) postoperative pathological examination and outcome of patients. Measurement data with normal distribution were expressed as Mean± SD, and measurement data with skewed distribution were expressed as M(IQR). Count data were expressed as absolute numbers or percentages. Results:(1) Surgical situations. Of 240 patients, 15 cases underwent combined vascular resection and reconstruction, and 13 patients were combined with other operations simultaneously. Of 240 patients, 4 cases converted to open surgery, with the conversion rate as 1.67%. The operation time of 240 patients was 458(152)minutes, volume of intraopera-tive blood loss was 50(50)mL, intraoperative erythrocyte transfusion was required in 17 patients. The R 0 resection rate was 99.17%(238/240), the number of lymph nodes harvested was 10(6) and duration of postoperative hospital stay was 17(12)days. (2) Postoperative pathological examination and outcome of patients. Of 240 patients, 51 cases were pancreatic ductal adenocarcinoma, 41 cases were ampullary carcinoma, 41 cases were neuroendocrine neoplasms, 35 cases were pancreatic cystic neoplasms, 28 cases were duodenal carcinoma and 44 cases were other pathologic types. Of 99 patients with major complications, there were 57 cases with clinically relevant postoperative pancreatic fistula, 44 cases with postoperative delayed gastric empty, 11 cases with postoperative biliary fistula, 8 cases with postoperative chyle fistula, 14 cases with incision infec-tion, and 24 cases with postoperative hemorrhage. Multiple complications might occur to the same patient. Reoperation was performed in 6 of the 240 patients. One patient died within 30 days after surgery. Twenty-four patients returned to hospital within 30 days after discharge. Conclusions:RPD performed by one single surgeon is safe and feasible, with favorable short-term outcomes, which can be performed in medical centers with experiences in robot-assisted pancreatic surgery.

Objective:To evaluate the safety and short-term efficacy of robotic-assisted resection for Bismuth-Corlette type Ⅲ and Ⅳ perihilar cholangiocarcinoma in Department of Pancreatobiliary Surgery,The First Affiliated Hospital,Sun Yat-sen University Methods:The clinical data of Bismuth-Corlette type Ⅲ and Ⅳ perihilar cholangiocarcinoma patients who have undergone robotic-assisted resection at The First Affiliated Hospital,Sun Yat-sen University between July 2017 and May 2023 were retrospectively studied.The clinicopathological features and perioperative outcomes of the patients were analyzed. Results:A total of 9 patients with Bismuth-Corlette type Ⅲ or Ⅳ perihilar cholangiocarcinoma,including 4 type Ⅲa patients,4 type Ⅲ b patients and 1 type Ⅳ patient,received robotic-assisted resection.1 patient converted to open surgery.The median operation time was 645 min[interquartile range(IQR):554-745 min],the median intraoperative blood loss was 300 mL(IQR:150-650 mL),and the median number of lymph node retrieval was 11(IQR:6-12).7 patients(77.8％)had R0 resection.5 patients(55.6％)had postoperative major complications(Clavein-Dindo classification was Ⅲ-Ⅴ),including intra-abdominal infection in 2 patients,liver function failure in 2 patients and upper gastrointestinal bleeding in 1 patient.1 patient underwent reoperation for the jejuno-jejunostomy bleeding 19 d after the initial operation and achieved good recovery.1 patient died within 30 d after initial operation due to liver function failure.The median length of postoperative hospital stay was 18 d(IQR:10-32 d). Conclusion:Robotic-assisted resection for Bismuth-Corlette type Ⅲ and Ⅳ perihilar cholangio-carcinoma is technically feasible and safe with good short-term efficacy,and can be performed in large-volume centers with ample experience in robotic-assisted hepatopancreatobiliary surgery.

Adipose progenitor cells(APCs) represent a prominent stromal cellular component of adipose tissue and are now identified as highly heterogenous populations. However, the role of APCs in regulating systemic metabolism remains unknown. Using single cell RNA-sequencing, we investigated the role of the APC subpopulations in regulating development of type 2 diabetes. CD9 + CD55 low APCs are the novel subset identified in this study, which is significantly increased in type 2 diabetic patients. Transplantation of these cells from type 2 diabetic patients into adipose tissue caused glycemic disturbance in mice. Depletion of pathogenic APCs improved obesity-related glycemic disturbance. Collectively, our data provide deeper insights into human APC functionality and highlights APCs as a potential therapeutic target to combat type 2 diabetes. This study has been published in Nature Communications, 2024, 15(1): 4827.