Advances in the biosynthesis of pentostatin / 生物工程学报

Pentostatin is a nucleoside antibiotics with a strong inhibitory effect on adenosine deaminase, and is widely used in the clinical treatment of malignant tumors. However, the high cost hampers its application. In the past 10 years, the biosynthesis of pentostatin were focused on strain breeding, optimization of medium composition and fermentation process. To date, there are no reviews summarizing the elucidated biosynthetic mechanism of pentostatin. This review starts by introducing the various chemical route for production of pentostatin, followed by summarizing the mechanisms of pentostatin biosynthesis in different microorganisms. Finally, challenges for biosynthesis of pentostatin were discussed, and strategies for regulating and improving the microbial synthesis of pentostatin were proposed.

Application value of single-port inflatable mediastinoscopy combined with laparoscopy in the radical resection of esophageal cancer / 中华消化外科杂志

Objective To explore the application value of single-port inflatable mediastinoscopy combined with laparoscopy in the radical resection of esophageal cancer.Methods The retrospective descriptive study was conducted.The clinicopathological data of 27 patients who underwent single-port inflatable mediastinoscopic and laparoscopic radical resection of esophageal cancer in the General Hospital of Ningxia Medical University between September 2016 and April 2018 were collected.The surgical operators were divided into neck operation group and abdomen operation group.A "Y" tube was used to inflate the abdomen and mediastinum simultaneously with CO2,and the gas pressure was 12-16 mmHg (1 mmHg =0.133 kPa).Bilateral exchange free and join forces with the esophagus and xiphoid process operating small incision,the severed esophagus cardia;residual stomach was made into a 3-5 cm tubular stomach and was sutured at the top point;at the same time,esophagus was brought up from the neck,with a pouch suture between upper esophageal and stapling head;the tubular stomach through mediastinum-esophagus bed was pulled to the left neck and then gastroesophageal anastomosis manually or instrument was performed.Observation indicators:(1) surgical and postoperative recovery;(2) follow-up and survival situations.Follow-up using outpatient examination and telephone interview was performed to detect postoperative survival up to May 2018.The measurement data with normal distribution were represented as x-±s.The measurement data with skewed distribution were described as M (range).Results (1) Surgical and postoperative recovery:all the 27 patients underwent successful single-port inflatable mediastinoscopic and laparoscopic radical resection of esophageal cancer,with complete tumor resection and without conversion to open surgery.There was no arrhythmia or myocardial ischemia through intraoperative electrocardiography.Among 27 patients,5 had intraoperative rupture of the pleura and 3 stopped intermittently inflation with CO2 due to obvious hemodynamic changes.The operation time and volume of intraoperative blood loss were (121±21)minutes and (100± 30)mL.Twenty-seven patients had no thoracic incision,obviously decreased postoperative pain and out-of-bed activity at day 1 postoperatively.The volume of postoperative mediastinal drainage was (40± 10)mL.The mediastinal drainage-tube was removed at 1 week after regular food intake.Of 27 patients,5 with pleural effusion were cured by puncture drainage;2 were complicated with anastomotic leakage,1 of them with a small amount of subcutaneous gas under neck incision at 12 days postoperatively was cured spontaneously through oral food intake,without special treatment,and the other had a small amount of subcutaneous gas under neck incision after solid food intake at 1 month postoperatively and then was cured after 1-week fluid food intake;1 with anastomotic stenosis was improved after dilation treatment.The squamous cell carcinoma was confirmed by postoperative pathological examination,without cancer cell infiltration in the upper and lower margins.The numbers of mediastinal lymph node dissected,abdominal lymph nodes dissected and positive lymph node,postoperative pathological staging and duration of hospital stay were respectively 9.5±2.2,8.2±2.5,1 (range,0-12),T1-3N0-1M0 and 13 days (range,11-21 days).(2) Follow-up and survival situations:27 patients were followed up for 1-20 months,with a median time of 10 months.During the follow-up,there was no recurrence or metastasis and death.Conclusion The single-port inflatable mediastinoscopy combined with laparoscopy in the radical resection of esophageal cancer is safe and effective,and it is especially suitable for patients with partial respiratory failure and closed thoracic cavity.

The reason of skin flap necrosis caused by vascular crisis of reverse island flap of forearm posterior interosseous artery / 中华显微外科杂志

Objective To discuss the reason of skin flap necrosis caused by vascular crisis of reverse island flap of forearm posterior interosseous artery.Methods Eight-six patients who were underwent reverse island flap of forearm interosseous posterior artery for deep tissues and skin defect on the back of hand between March,2002 and April,2014 were analyzed in this study.Eleven patients had occurred skin flap necrosis,include 5 cases had completely flap necrosis caused by circulation crisis,and 6 cases had partial necrosis at the distal of the flap.Among the necrosis cases,5 cases were injured by the machine injury,4 cases by the heavy crush and 2 cases by the traffic accident.The cause of circulation crisis was analyzed.Results In the series,75 skin flaps survived completely and 11 cases had occurred necrosis,included completely necrosis with 5 cases.The reasons of flap crisis were as follows:for the completely necrosis,2 cases with variation of perforating branch of posterior interosseous artery,1 case with absence of posterior interosseous artery,1 case with vessel pedicel entrapment in subcutaneous tunnel,and 1 case with misconduct venous congestion caused by the reverse perfusion of superficial vein.The reason of circulation crisis of completely necrosis were as follows:2 cases with artery crisis and 3 of them with distortion of entrapment at pedicel and vein crisis.One case was cured through debridement,change of medical prescription and skin grafting;and 4 cases were cured with other flap repair technique.For the partial necrosis,2 cases with variation of perforating branch of posterior interosseous artery,1 case with excessively narrow entrapment at pedicel in subcutaneous tunnel,1 case with folding vessel pedicel entrapment of skin at the back of wrist,1 case with misconduct of superficial vein trunk and 1 case with intraoperative side-injury.The symptoms of circulation crisis of completely necrosis were as follows:2 cases with artery crisis and 4 of them with distortion of entrapment at pedicel and vein crisis.Four cases were cured through debridement and skin grafting,1 case was cured by the vacuum-sealing drainage (VSD) and 1 case with skin flap repair at pedicle of abdomen.Conclusion The anatomic variation of perforator vessel of reverse island flap of forearm posterior interosseous artery;narrow entrapment at pedicel in subcutaneous tunnel and distortion of entrapment at pedicel;venous congestion caused by the reverse perfusion of superficial vein;intraoperative side-injury of the pedicel of the flap;excessively folding vessel pedicel entrapment of skin at the back of wrist after surgery will cause the circulation crisis of reverse island flap of forearm posterior interosseous artery and induce the necrosis of the skin flap.

AFLP analysis of genetic diversity of Evodia rutaecarpa / 中国中药杂志

<p><b>OBJECTIVE</b>To study the genetic background of Evodia rutaecarpa by AFLP, and analyze the genetic diversity of E. rutaecarpa from different areas.</p><p><b>METHOD</b>E. rutaecarpa genomic DNA was extracted. The AFLP reaction system was established and AFLP primer pairs were chosen for the analysis. Forty-six individuals of E. rutaecarpa which from five provinces were analyzed by AFLP. The NTSYS-pc 2.1 software was used for cluster analysis.</p><p><b>RESULT</b>Six out of the original 72 pairs of primers were optimized for the study; AFLP analysis revealed the similarity coefficient of 0.53, the samples of E. rutaecarpa var. officinalis from Zhejiang province was separated from other accessions; E. rutaecarpa var. officinalis also showed more pronounced genetic variation than the E. rutaecarpa, and strong geo-related relevance.</p><p><b>CONCLUSION</b>Variance of genetic background of E. rutaecarpa are large, AFLP analysis method can obviously identify different varieties of E. rutaecarpa, and can detect the genetic characteristics of inter-regional differences.</p>

The Novel Noncoding Small RNA: Piwi-interacting RNA(piRNA) / 生物化学与生物物理进展

piRNA is a novel class of small single strand RNA that were recently isolated from testes of the mammals. These RNAs are bigger (26～31 nt) than most previously described small RNAs (21～23 nt) and are associated with Piwi-subfamily members of the Argonaute protein family.

Effect of Catechin on Glomerular Visceral Epithelium Cells Proliferation / 中国医师杂志

catechin plus dexamethasone-treated group. Compared with nephrotic group, the renal pathologic score were significantly different among the nephrotic group and the catechin-treated group (6 80?0 84,P

EFFECT OF UNDARIA PINNATIFIDA DIETARY FIBER ON VASCULAR ENDOTHELIUM IN HYPERLIPIDEMIC RATS / 营养学报

Objective To test the effect of Undaria pinnatifida soluble dietary fiber on endothelial function in hyperlipidemic rats. Method Forty rats were divided into 4 groups(n=10) :control group,hyperlipidemic model group,low dose dietary fiber-treated group(5%) ,high dose dietary fiber-treated group(10%) . After treatment for 8 w. Endothelium-dependent vasorelaxation in isolated aortic rings,the content of plasma malondialdohyde(MDA) ,nitric oxide(NO) and endothelin-1(ET-1) were determined. The protein expression of endothelial NO synthase(eNOS) was measured by Western blotting. Results Undaria pinnatifida soluble dietary fiber treatment significantly decreased MDA and ET-1 level. It also significantly improved endothelial function and plasma NO level concomitantly with unregulation of the expression of eNOS protein. Conclusion In hyperlipidemic rats Undaria pinnatifida soluble dietary fiber could improve vascular endotheliual function,which might be explained by its action to decreasing plasma ET-1 level and increased NO production.