ABSTRACT
Objective:To investigate the application value of P-loop digestive tract recons-truction in pancreaticoduodenectomy (PD).Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 21 ampullary disease patients undergoing PD in the Liuzhou People′s Hospital Affiliated to Guangxi Medical University from April to December 2020 were collected. There were 13 males and 8 females, aged from 35 to 76 years, with a median age of 60 years. All the 21 patients underwent PD and digestive tract reconstruction using P-loop method based on the Child reconstruction. Observation indicators: (1) surgical situations; (2) postoperative situations; (3) follow-up. Follow-up was conducted using outpatient examination or telephone interview to detect survival and discomfort symptoms of patients up to December 2020. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range). Count data were described as absolute numbers or persentages. Results:(1) Surgical situations: all the 21 patients underwent PD successfully. The operation time, time of P-loop anastomosis and volume of intraoperative blood loss of 21 patients were (317±74)minutes, (14±3)minutes and 375 mL(range, 100-800 mL), respectively. Of the 21 patients, 17 cases had pancreatic texture as soft, 4 cases had pancreatic texture as hard, 3 cases had diameter of pancreas ≤3 mm, 18 cases had diameter of pancreas >3 mm, 14 cases were placed pancreatic duct stent, 7 cases were not placed pancreatic duct stent. (2) Postoperative situations: 2 of the 21 patients had grade A pancreatic fistula, and none of patient had grade B or grade C pancreatic fistula. One case had hepaticojejunal anastomotic fistula, 2 cases without pancreatic fistula had delayed gastric emptying and none of patient had abdominal infection or bleeding. The duration of postoperative hospital stay of 21 patients was (16±5)days, and none of patient died during postoperative 30 days. Results of postoperative histopathological examination showed there were 10 cases with duodenal papillary carcinoma, 4 cases with lower bile duct carcinoma, 3 cases with pancreatic head ductal adenocarcinoma, 1 case with duodenum stromal tumors, 1 case with gastric antrum carcinoma, 1 case with mass in the head of the pancreas of IgG4 and 1 case with choledochal cyst of type 3. (3) Follow-up: all 21 patients were followed up for 1.0 to 7.0 months, with a median follow-up time of 4.3 months. None of patient died. There was no abdominal pain, distension or dyspepsia during follow-up. One case was diagnosed as tumor liver metastasis at postoperative 5 months.Conclusion:P-loop digestive tract reconstruction in PD is safe and effective, with good short-term effect.
ABSTRACT
Structures of crystals of Mycobacterium tuberculosis RecA, grown and analysed under different conditions, provide insights into hitherto underappreciated details of molecular structure and plasticity. In particular, they yield information on the invariant and variable features of the geometry of the P-loop, whose binding to ATP is central for all the biochemical activities of RecA. The strengths of interaction of the ligands with the P-loop reveal significant differences. This in turn affects the magnitude of the motion of the ‘switch’ residue, Gln195 in M. tuberculosis RecA, which triggers the transmission of ATP-mediated allosteric information to the DNA binding region. M. tuberculosis RecA is substantially rigid compared with its counterparts from M. smegmatis and E. coli, which exhibit concerted internal molecular mobility. The interspecies variability in the plasticity of the two mycobacterial proteins is particularly surprising as they have similar sequence and 3D structure. Details of the interactions of ligands with the protein, characterized in the structures reported here, could be useful for design of inhibitors against M. tuberculosis RecA.