Clinical experience with near-infrared ray catheter, a fluorescent ureteral catheter, on laparoscopic surgery for colon diverticulitis: A case report.

RATIONALE: As the world's population ages, the number of surgical cases of colovesical fistulas secondary to colon diverticulitis is also expected to increase. The key issue while performing laparoscopic surgery for these fistulas is the avoidance of iatrogenic ureteral injury. There are no reports of Near-infrared Ray Catheter being used in surgery for diverticulitis, which is one of the diseases with the highest risk of ureteral injury. We present a case of a male patient with colovesical fistulas secondary to sigmoid colon diverticulitis who underwent laparoscopic surgery with visualization of the ureter using a new surgical technique in laparoscopic surgery. PATIENTS CONCERN: An 82-year-old man presented to our urological department with general fatigue and air and fecal matter in the urine. DIAGNOSES: Cystography showed delineation of the sigmoid colon. Abdominal computed tomography findings revealed multiple sigmoid colon diverticula with thickened walls as well as large stones and a small amount of air in the bladder. He was diagnosed with a urinary tract infection with colovesical fistulas and bladder stones due to sigmoid diverticulitis. INTERVENTIONS: After the creation of a transverse colostomy, we scheduled a laparoscopic anterior resection and cystolith removal. OUTCOMES: Severe inflammatory adhesions around the sigmoid colon and a high risk of ureteral injury were expected preoperatively. After induction of anesthesia, we inserted a Near-infrared Ray Catheter, a fluorescent ureteral catheter, which allowed us to easily identify and visualize the ureter in real-time. This allowed bowel dissection without concerns of ureteral injury. The operative time for the gastrointestinal part of the procedure was 150 minutes, and the patient was in a good general condition after the operation and was discharged on postoperative day 7. LESSONS: The course of the ureter was easily and quickly identified by the green fluorescence from the ureteral catheter during laparoscopic surgery for fistulas associated with diverticulitis, where severe inflammation and dense fibrosis were present. Our technique is an easy and feasible approach that provides real-time urethral navigation during surgery for colovesical fistulas secondary to colon diverticulitis.

Closure of enterotomy after side-to-side ileocolic anastomosis with two barbed sutures in totally laparoscopic colectomy for right-sided colon cancer.

Good short-term outcomes of intracorporeal ileocolic anastomosis (IIA) in totally laparoscopic colectomy for right-sided colon cancer (TLRC) have been shown in many reports, but no standardized technique for enterotomy closure after stapled side-to-side ileocolic anastomosis has so far been established. We retrospectively compared the short-term outcomes between 13 consecutive patients receiving either TLRC with IIA by conventional enterotomy closure (n = 6) or closure of the enterotomy using two barbed sutures (CEBAS) (n = 7) from July 2019 to April 2020. No anastomotic bleeding or leakage was observed in either group. Time to enterotomy closure was significantly shorter with the CEBAS method (16.5 ± 3.7 min) than with the conventional method (24.5 ± 4.7 min, p = 0.0059). The CEBAS method in TLRC with IIA was thus found to be technically feasible and it might reduce the stress associated with intracorporeal enterotomy closure.

A new spray-type adhesion barrier (AdSpray) improves condition for surgical treatment in the reversal of Hartmann procedure: A case report.

RATIONALE: Hartmann procedure (HP) often causes severe postoperative adhesions in the pelvic space; therefore, the reversal of Hartmann procedure (RHP) is a challenging surgery. A new spray-type antiadhesion agent, AdSpray, has been reported to be useful in three-dimensional fields such as the liver. However, there are no reports of its use in HP. We present a case of a male patient with rectal cancer who underwent laparoscopic HP with AdSpray to prevent postoperative adhesions. PATIENT CONCERNS: A 52-year-old man presented with melena and constipation. DIAGNOSIS: Colonoscopy revealed an almost obstructive type II tumor at the rectosigmoid colon, and histopathological examination revealed moderately differentiated adenocarcinoma. Enhanced abdominal computed tomography revealed slightly enlarged regional lymph nodes but no ascites around the tumor, and there was no metastasis to the liver or lungs. Therefore, we diagnosed clinical stage T4aN1bM0 rectosigmoid colon cancer. Intraoperatively, a metastatic tumor of the liver surface and a high degree of valve retention in the oral colon were identified. INTERVENTIONS: After performing laparoscopic HP with AdSpray, we scheduled a laparoscopic RHP with staged hepatic surgery for synchronous liver metastasis from colorectal cancer 1 month later. OUTCOMES: No postoperative inflammatory adhesions were observed in the pelvis or around the rectal stump, allowing us to perform RHP by a single-incision laparoscopic surgery from the stoma site without any problem. The operation time for RHP was 80 minutes; the patient was in good general condition after the operation, and he was discharged on postoperative day 7. LESSONS: In laparoscopic HP, Adspray was easy to use for three-dimensional fields such as the pelvis and effectively prevented postoperative inflammatory adhesions. Thus, RHP may become less risky and be performed more as a minimally invasive surgery.

A Lynch syndrome-associated mutation at a Bergerat ATP-binding fold destabilizes the structure of the DNA mismatch repair endonuclease MutL.

In humans, mutations in genes encoding homologs of the DNA mismatch repair endonuclease MutL cause a hereditary cancer that is known as Lynch syndrome. Here, we determined the crystal structures of the N-terminal domain (NTD) of MutL from the thermophilic eubacterium Aquifex aeolicus (aqMutL) complexed with ATP analogs at 1.69-1.73 Å. The structures revealed significant structural similarities to those of a human MutL homolog, postmeiotic segregation increased 2 (PMS2). We introduced five Lynch syndrome-associated mutations clinically found in human PMS2 into the aqMutL NTD and investigated the protein stability, ATPase activity, and DNA-binding ability of these protein variants. Among the mutations studied, the most unexpected results were obtained for the residue Ser34. Ser34 (Ser46 in PMS2) is located at a previously identified Bergerat ATP-binding fold. We found that the S34I aqMutL NTD retains ATPase and DNA-binding activities. Interestingly, CD spectrometry and trypsin-limited proteolysis indicated the disruption of a secondary structure element of the S34I NTD, destabilizing the overall structure of the aqMutL NTD. In agreement with this, the recombinant human PMS2 S46I NTD was easily digested in the host Escherichia coli cells. Moreover, other mutations resulted in reduced DNA-binding or ATPase activity. In summary, using the thermostable aqMutL protein as a model molecule, we have experimentally determined the effects of the mutations on MutL endonuclease; we discuss the pathological effects of the corresponding mutations in human PMS2.