Evaluation of parameters for efficient purification and long-term storage of herpes simplex virus-based vectors.

Replication competent oncolytic herpes simplex virus (HSV) vectors have been used extensively to treat solid tumors with promising results. However, highly defective HSV vectors will be needed for applications that require sustained therapeutic gene expression in the absence of vector-related toxicity or inflammation. These vectors require complementing cell lines for their manufacture, creating significant challenges to achieve high yields of infectious virus particles. We recently described an improved upstream process for the production of a non-cytotoxic HSV vector for gene therapy applications. Here, we sought to optimize the downstream conditions for purification and long-term storage of the same vector, JΔNI5. We compared different methods to remove cellular impurities and concentrate the vector by monitoring both physical and biological titers, resulting in the establishment of optimal conditions for vector production. To optimize the long-term storage parameters for non-cytotoxic HSV vectors, we evaluated vector stability at low temperature and sensitivity to freeze-thaw cycles. We report that suboptimal purification and storage methods resulted in loss of vector viability. Our results describe effective and reproducible protocols for purification and storage of HSV vectors for pre-clinical studies.

Förster resonance energy transfer (FRET)-Labeled nanoprobe enables real-time diagnosis of pancreatic juice activation due to postoperative pancreatic fistula.

OBJECTIVES: Postoperative pancreatic fistula (POPF) subsequent to pancreatectomy often causes activation of pancreatic juice, resulting in serious complications. In POPF, the types of pancreatic juices found are active and inactive, and the identification of these two types of pancreatic juice greatly contributes to the development of postoperative management after pancreatectomy. This study reports favorable results of the clinical application of the Förster resonance energy transfer (FRET) nanoprobe that was independently developed to distinguish between the active and inactive types of pancreatic juice. METHODS: The FRET nanoprobe developed was a nanoprotein capsule. It exuded a red color when the capsule structure was maintained. When activated protease in the pancreatic juice acts on it, the capsules are reduced quantitatively and FRET is abolished, resulting in a change in color from red to green. Pancreatic juice activation can be measured by the FRET signal. A total of 117 drainage fluid samples from 16 postpancreatoduodenectomy cases were obtained and evaluated. RESULTS: The diagnosis of pancreatic juice activation was possible using the FRET signal with a cut-off value of 1.6. Pancreatic juice activation was not associated with drainage fluid amylase (AMY) levels. The results demonstrated that pancreatic juice was activated when drainage fluid was infected. CONCLUSION: The use of a FRET nanoprobe enabled real-time detection of the presence or absence of pancreatic juice activation in pancreatic fistula after pancreatic surgery. There was an adequate correlation between infection and pancreatic juice activation regardless of drain AMY levels.

Absorbable barbed suture device for laparoscopic peritoneal closure after hernia repair via the transabdominal preperitoneal approach: A single-center experience with 257 cases.

INTRODUCTION: The laparoscopic transabdominal preperitoneal approach requires peritoneal closure and technically skilled knotting. We have started to use a barbed running suturing device (V-Loc 180) without knotting for transabdominal preperitoneal repair of hernias. This study aimed to determine whether using V-Loc 180 was safe and shortened the time for laparoscopic peritoneal closure. METHODS: Between December 2010 and February 2017, 3-0 V-Loc 180 and a multifilament absorbable running suture (3-0 Vicryl) were used for three-port transabdominal preperitoneal repair of inguinal hernia in 363 cases. Data including peritoneal closure time and the complications were retrospectively recorded. RESULTS: Factors identified as significantly prolonging the peritoneal closure time were the hernia side (P = 0.0269), the type of hernia (P = 0.001), the suture device used (P < 0.0001), and the surgeon's experience (P < 0.0001). Use of the barbed suture was associated with a significantly shorter peritoneal closure time than the multifilament suture (mean closure time: 10.2 and 12.7 min, respectively). While there were no postoperative complications in the barbed suture group, there were two cases (1.9%) of postoperative complications in the multifilament suture group (P = 0.0272). CONCLUSION: We demonstrated that the use of the barbed suturing device for laparoscopic peritoneal closure was safe and feasible.

Is the Laparoscopic Approach Feasible for Reduction and Herniorrhaphy in Cases of Acutely Incarcerated/Strangulated Groin and Obturator Hernia?: 17-Year Experience from Open to Laparoscopic Approach.

Purpose: Management strategies for acutely incarcerated/strangulated groin and obturator hernias may differ from institution to institution, although, conventionally, the open approach has been used. Recently, laparoscopic transabdominal preperitoneal (TAPP) repair and totally extraperitoneal (TEP) repair have become commonly used operative procedures for the repair of groin hernias. It is unclear whether laparoscopic reduction and herniorrhaphy can be successfully accomplished in all cases. This study was aimed at assessing the effectiveness of laparoscopic treatment. Methods: We conducted a prospective clinical trial of the laparoscopic approach from December 2011 and comparatively analyzed the surgical outcomes between the open and laparoscopic approaches for incarcerated/strangulated hernias seen from December 2000 to March 2017. Results: The open approach for repair was used in 54 patients (50.9%) and the laparoscopic approach in 52 patients (49.1%). There was 1 case in which from the laparoscopic approach to laparotomy (1.9%) was required. The operation time treated by the laparoscopic approach was significantly longer than the open approach (126.4 minutes versus 104.6 minutes; P = .0079); however, the incidence of postoperative complications and the postoperative length of hospitalization were also less in the former group than in the latter group (3.9% versus 18.5%; P = .0172 and 5.6 days versus 14.7 days; P = .0096). Second-stage TAPP herniorrhaphy was performed in 7 patients (15.2%) after bowel resection or closure of bowel perforation, and first-stage TEP herniorrhaphy was performed in 1 patient after bowel resection. There was no case of mesh infection in the group treated by the laparoscopic approach, and there was 1 case of mesh infection in the group treated by the open approach. The mortality rate was 0% in the group treated by the laparoscopic approach. Conclusions: Laparoscopic reduction and herniorrhaphy for acutely incarcerated/strangulated groin and obturator hernias is effective, safe, and feasible.