Surgical skills in the prevention of anastomotic leakage after rectal neoplasm surgery / 中华胃肠外科杂志

For colorectal surgeons, how to reduce anastomotic leakage after laparoscopic rectal cancer surgery remains to be challenging. We provide a brief discussion regarding the surgical skills required to prevent anastomotic leakage after rectal cancer surgery, such as the following: 1) Low ligation of inferior mesenteric vessel during laparoscopic total mesorectal excision can improve anastomotic tension and blood supply, thus reducing the risk of anastomotic leakage.While high ligation of inferior mesenteric artery resultsin poor blood supply and high tension in atastomotic site, thus increasing the risk of anastomotic leakage. 2) Protective enterostomy is recommended for patients with high risk of developing anastomotic leakage. 3) Use of abdominal/pelvic drains after colorectal anastomosis is recommended to decrease the incidence of anastomotic leakage, early detect anastomotic leakage, and conservativdy manage anastomotic leackage through drainage of pelvic effusion. 4) Laparoscopic reinforcing sutures should be used if anastomotic tension and blood supply are unsatisfactory, including continuous suture with 3-0 or 4-0 absorbable suture and 2-needle interrupted suture in the weak anastomosis. However, these sutures should be performed by experienced surgeons. For male patients with narrow pelvis and those with low rectal cancer, laparoscopic reinforcing sutures should be performed carefully due to the limited operative space. 5) Intraoperative air leak test is recommended to identify the anastomotic integrity for those with suspicious mechanically insufficient rectal anastomosis. 6) Experienced surgeon can reduce the incidence of anastomotic leakage after rectal cancer operation.

Transanal endoscopic microsurgery for treatment of rectal neuroendocrine tumors / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To assess the efficacy of full-thickness excision using transanal endoscopic microsurgery (TEM) in the treatment of rectal neuroendocrine tumors (NET).</p><p><b>METHODS</b>Clinicopathological and follow-up data of 90 rectal NET patients who underwent TEM between December 2006 and December 2016 at our department were retrospectively analyzed. TEM was performed as primary excision in 66 patients and as the second complete surgery because of suspected positive margin of samples after colonoscopic polypectomy in 24 patients.</p><p><b>RESULTS</b>TEM was successfully performed in all the rectal NET patients, and in 10 patients(41.7%,10/24) among those undergoing the second excision, postoperative pathologic results showed remnant tumor. The mean diameter of all the tumors was (1.03±0.46) cm, and the mean tumor diameter of primary excision and secondary excision was (1.10±0.50) and (0.84±0.23) cm respectively (t=2.454, P=0.016). The mean distance from tumor low margin to anal verge was (7.7±1.8) cm for all the patients, and such distance for those undergoing primary excision and secondary excision was (7.4±1.7) cm and (8.4±1.8) cm respectively (t=2.233, P=0.028). Of all the patients, the mean intra-operative blood loss was (13.7±5.1) ml, and the mean operation time was (56.6±12.1) min. The intra-operative blood loss and operative time were similar in primary excision and secondary excision (both P>0.05). Histopathologically, both fundus and lateral margins of all the samples were negative. Of the 76 samples, cancer tissue developed outside the mucosal layer in 37 samples, infiltrated into the submucosal layer (pT1 stage) in 33 samples, and infiltrated into the muscular layer (pT2 stage) in 6 samples; 57 samples were classified as grade G1 and 19 samples were classified as grade G2, respectively. The operative complication rate was 6.7%(6/90). The mean postoperative hospital stay was (3.0±1.5) d. No recurrence was noted during the follow-up (median 3.9, 0.4 to 10.0 years).</p><p><b>CONCLUSIONS</b>TEM can be the preferred option for complete removal of middle-upper small (<2 cm) rectal NET(G1-2). For rectal NET with incomplete resection by colonoscopic polypectomy, the secondary TEM can still obtain ideal efficacy even though operative difficulty increases.</p>

Hypoxia regulates osteopontin expression of mature dendritic cells via adenosine 2 receptor / 中华微生物学和免疫学杂志

Objective To investigate the mechanism of hypoxia regulate osteopontin (OPN) secreting by mature dendritic cells (mDCs). Methods CD14 + cells were enriched using anti-CD14 immunomagnetic beads, for inducing to mDCs, CD14 + cells were cultured with GM-CSF and IL-4 in hypoxia or normoxiain vitro. Concentration of OPN and TGF-β1 in supernatant were detected by sandwich ELISA, OPN mRNA detected by RT-PCR. Approach regulating function of A2 R in expressing of OPN by mDCs by using NECA (surrogate of adenosine), A2R agonist (CGS21680), A2R antagonist (SCH58261) and investigate role of TGF-β1 in this process by using rhTGF-β1 and anti-TGF-β1 Ab. Results Hypoxia inreased the level of OPN and OPN mRNA in mDCs, and this effect could be reversed by A2 R antagonist. Under normoxia,both NECA and A2R agonist (CGS21680) could upregulate the level of OPN and OPN mRNA in mDCs significantly, but this positive effect could be reversed by A2 R antagonist. A2 R played a role in regulating TGF-β1, and confirmed TGF-β1 involved in regulation of OPN by using rhTGF-β1 and anti-TGF-β1 Ab. Conclusion High adenosine induce the generation of TGF-β1 through the A2R on mDCs, and then TGF-β1 raise the OPN secreting by mDCs.