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Trehalase is widely used in industrial fermentation, food, medicine and other fields. There is a lack of industrial varieties of trehalase with excellent performance in China. Moreover, the applied research on trehalase was not well conducted. In this study, a strain of Pectobacterium cypripedii was screened from nature, and the gene PCTre encoding an acidic trehalase was cloned and expressed in E. coli BL21(DE3). The highest enzyme activity reached 4130 U/mL after fermenting in a 5 L fermenter for 28 h. The enzymatic properties study showed that PCTre hydrolyzed trehalose specifically. The optimum pH and temperature were 5.5 and 35 ℃, respectively. 80% of the enzyme activity was retained after being treated at pH 4.0, 4.5, and 5.0 for 8 h, showing good acid tolerance. Moreover, it has good tolerance to organic solvents, 60% enzyme activity was retained after being treated with 20% (V/V) ethanol solution for 24 h. Furthermore, trehalose could be completely hydrolyzed within 16 h in a simulated fermentation system containing 20% (V/V) ethanol and 7.5% trehalose, with 500 U/L PCTre added. This indicated a good application potential for industrial ethanol fermentation.
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Trehalase/metabolism , Trehalose/metabolism , Escherichia coli/metabolism , Ethanol/metabolism , Cloning, MolecularABSTRACT
Objective:To evaluate the safety and efficacy of endoscopic ultrasound (EUS)-guided iodine-125 seed implantation to treat dysphagia in patients with advanced esophageal cancer.Methods:Data of 4 patients with dysphagia of advanced esophageal cancer who received EUS-guided iodine-125 seed implantation in Chinese PLA General Hospital between December 2017 and November 2018 were collected in the retrospective study. The evaluation contents included technical success rate of seed implantation, complication, dysphagia grade, tumor size and other follow-up results.Results:Four patients successfully completed EUS-guided iodine-125 seed implantation. No haemorrhage, chest pain, fever, cough or other postoperative complications were reported. Three months after treatment, dysphagia grade reduced from Ⅱ-Ⅳ to 0-Ⅰ, and the tumor size in all patients showed a decrease. After 12-23 months of follow-up, 3 patients were alive, and 1 died due to advance of the cancer.Conclusion:EUS-guided iodine-125 seed implantation is a safe and effective palliative treatment method for dysphagia in patients with advanced esophageal cancer.
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Objective To evaluate the feasibility and safety of the robot - assisted system YunSRobot for remote manipulation endoscopy. Methods When the master of YunSRobot was installed in the gastroenterology office in Chinese PLA General Hospital, the robot slave and upper gastrointestinal simulation model (Takahashi Lm103,Japan) were installed at the same time in the State Key Laboratory of Robotics, Shenyang Institute of Automation. Three physicians were trained to operate the master robotics and performed gastroscopy on the simulation model based on network cloud. Each physician performed 3 procedures of oesophagogastroduodenoscopy (EGD) by YunSRobot using traditional manual endoscopy, on-site operating mode, and remote manipulation mode, respectively. The operating time, lumenal anatomic exposure,man-machine interaction and other parameters were recorded. Results The number of standard pictures obtained by traditional manual endoscopy group, on-site operating group and remote manipulation group were 39.9±0.3, 39.8±0.4, 39.9±0.3, respectively. The images of all five lesions could be obtained by each operation. The operating time in the duodenum of remote group was longer than that of on-site group, with average time (78.2±16.0)s vs. (68.9±15.8)s (P=0.021) respectively. As to the operating time on other parts or total time, all three groups were comparable. Although there was a mean delay of (572.1±48.5) ms in remote operation group, the operation was still smooth. However, compared with on-site group, the percentage of clear view time in the duodenum was significantly shortened in remote group: [(77.8±8.2)% vs. (83.9 ± 6.4)% , P=0.024]. Statistically significant difference was detected in percentage of clear view time neither in other sites, nor was in the total operating time between two groups. The operating time in each part of remote group was obviously longer than that of manual group as followings, pharyngeal (27.3±4.2) s vs. (9.2±1.3)s (P<0.001), esophageal (29.7±6.4)s vs. (19.3±1.6)s (P=0.004), stomach (56.7±17.0)s vs. (40.3±7.0)s (P=0.003), pylorus (20.2±5.5)s vs. (9.3±1.3)s (P<0.001), duodenum (78.2±16.0)s vs. (29.3±5.6)s (P<0.001). Thus the total operating time was also longer in remote group as (559.0±87.2)s vs. (253.1±16.6)s (P<0.001). The respective time in pharynx, esophagus, stomach, pylorus, duodenum, or the overall time was all longer in remote group than that in manual group. Conclusions The soft endoscopy robot YunSRobot has satisfactory safety and stability. Remote upper gastrointestinal endoscopy can be completed based on common network and an endoscope simulation model with smooth operation. The inspection time by YunSRobot robot per part and the overall time are longer than those of manual operation on site, still, remote operating time meets the standard of upper gastrointestinal endoscopy.
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Objective To investigate the feasibility and safety of trans-gastric route combined with trans-colonic or trans-vaginal route endoscopic salpingectomy and liver biopsy, as methods of natural orifice translumenal endoscopic surgery (NOTES). Methods Endoscopic salpingectomy and liver biopsy were per-formed in 4 female porcine models, in 2 of which the procedure was achieved via trans-gastric and trans-co-Ionic route (Group A), while in other 2 was via trans-gastric and trans-vaginal route (Group B). The ani-mals were sacrificed after the procedure and the related complications were observed. Results Abdominal cavity exploration, salpingectomy and liver biopsy could be performed successfully through two combined routes. Perforation of adjacent colon was found in 1 animal with the trans-colonic route NOTES. Conclusion NOTES via trans-gastric and trans-colonic routes or via trans-gastric and trans-vaginal for salpingectomy and liver biopsy are both feasible, while trans-vaginal route seems to be safer than trans-colunic route.
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Objective To investigate the causes of success or failure of natural orifice translumenal endoscopic surgery(NOTES)in animals.Methods Data were collected from animal studies of NOTES carried out between August 2007 and September 2009.The studies were divided into acute phase and survival phase.In the studies,simple NOTES and laparoscopic-assisted NOTES were performed on female miniswines or adult mongrel dogs.Diagnostic abdominal exploration,liver biopsy,cholecystectomy,tubal ligation,oophorectomy,gastrojejunal anastomosis,and splenectomy were made in the animals.The intra-and post-operative complications and technical difficulties were recorded during the procedures.Results Totally 37 miniswines and 16 mongrel dogs were enrolled in the studies of NOTES procedures(91 procedures),including 22 acute experiments and 31 survival experiments.Simple NOTES was conducted through the transgastric route in 25 cases,transcolonic route in 8 cases,and combinations of transgastric and transcolonic routes in 16 cases,and combinations of transgastric and transvaginal routes in 6.In Laparoscopic-assisted cases,36 animals were treated via the transgastric route by traditional(26 cases)or single-port transumbilical laparoscopy(10 cases).Diagnostic exploration was carried out in 33 cases,liver biopsy was done in 11 cases,tubal ligation was made in 11,and oophorectomy was performed on 6;the procedures were all completed in these cases showing a success rate of 100%.Cholecystectomy was completed in 27 cases with a success rate of 44.4%(12/27).One case of splenectomy,and two cases of gastrojejunal anastomosis failed.The totally complication rate in the studies were 39.6%(21/53).The complications included perforation(8 cases),organ injury(5 cases),bleeding(4 cases),infection(3 cases)and pneumoperitoneum with hypertonia(1 case).Conclusions NOTES is feasible,safe and effective in diagnostic abdominal exploration and simple abdominal surgeries,but does not suit difficult abdominal surgeries.By using laparoscopy,the technique may be further developed and used in the future.