Using viral vectors as gene transfer tools (Cell Biology and Toxicology Special Issue: ETCS-UK 1 day meeting on genetic manipulation of cells)

In recent years, the development of powerful viral gene transfer techniques has greatly facilitated the study of gene function. This review summarises some of the viral delivery systems routinely used to mediate gene transfer into cell lines, primary cell cultures and in whole animal models. The systems described were originally discussed at a 1-day European Tissue Culture Society (ETCS-UK) workshop that was held at University College London on 1st April 2009. Recombinant-deficient viral vectors (viruses that are no longer able to replicate) are used to transduce dividing and post-mitotic cells, and they have been optimised to mediate regulatable, powerful, long-term and cell-specific expression. Hence, viral systems have become very widely used, especially in the field of neurobiology. This review introduces the main categories of viral vectors, focusing on their initial development and highlighting modifications and improvements made since their introduction. In particular, the use of specific promoters to restrict expression, translational enhancers and regulatory elements to boost expression from a single virion and the development of regulatable systems is described

Increased Surgical Duration Associated With Prolonged Hospital Stay After Isolated Posterior Cruciate Ligament Reconstruction

Hasani W Swindell,1 Venkat Boddapati,1 Julian J Sonnenfeld,1 David P Trofa,1 James E Fleischli,2 Christopher S Ahmad,1 Charles A Popkin1 1Department of Orthopedic Surgery, Columbia University Medical Center, New York, NY, USA; 2Shoulder and Elbow Center, OrthoCarolina Sports Medicine Center, Charlotte, NC, USACorrespondence: Charles A PopkinDepartment of Orthopedic Surgery, Columbia University Medical Center, 622 West 168th Street, PH – 11, New York, New York 10032, USATel +1 212-305-4787Email [email protected]: Although often performed using a variety of reconstructive techniques and strategies, no clinically significant differences presently exist between the approaches available for isolated PCL reconstructions. Given the operatively challenging nature of these procedures, there lies a potentially increased risk of postoperative complications and healthcare expenditures. Our investigation sought to identify patient and surgical risk factors associated with prolonged hospital stays following isolated PCL reconstruction and determine the incidence of 30-day complications after PCL reconstruction using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database.Method: Patients undergoing isolated PCL reconstructions between 2005 and 2016 were identified in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database using Current Procedural Terminology codes. Baseline patient and operative characteristics were evaluated as possible risk factors for overnight hospital admissions following PCL reconstruction and analyzed using multivariate analyses.Results: A total of 249 patients were identified. Multivariate analyses demonstrated that increased operative duration >120 mins (OR 5.04, CI 2.44–10.40; p <0.001) was associated with an increased risk of overnight hospital stay. Major complications occurred in 0.4% (N=1), and minor complications occurred in 0.8% (N=2) with overall complications occurring in 1.2% (N=3) of all patients. Wound dehiscence was the only major complication while superficial surgical site infection and deep vein thrombosis were the only minor complications. 34.1% (N=85) of patients required an overnight hospital stay postoperatively.Conclusion: Surgical duration >120 mins carried an increased risk of overnight hospital stay after isolated PCL reconstructions. As there are presently minimal significant clinical differences between current PCL reconstruction techniques, improved surgeon familiarity and comfort with a single technique is recommended to decrease operative time and avoid prolonged hospital stays and healthcare expenditures.Level of evidence: III, retrospective comparative study.Keywords: operative time, overnight hospital stays, healthcare expenditures, American College of Surgeons National Surgical Quality Improvement Program, NSQI

Plantar pressure in off-loading devices used in diabetic ulcer treatment

Four off-loading devices used for the treatment of diabetic forefoot ulcers were compared: a custom-molded insole shoe, a cast MABAL shoe, a prefabricated pneumatic walking brace, and a bivalved total contact cast (BTCC). It was anticipated that all devices would significantly reduce forefoot plantar pressure compared with a control shoe. Sixteen healthy volunteers participated. Plantar pressures were evaluated using the Pedar system, while walking speed was determined using an optoelectric timer. Peak pressure (PP) of ten plantar areas and pressure–time integral for the first metatarsal area were analyzed statistically using a repeated measures analysis of variance. Forefoot pressures were significantly reduced compared with the control shoe for all devices (p<0.001). PP was most reduced (by 65.8%) for the BTCC, and pressure–time integral was most reduced for the BTCC and cast MABAL shoe. Small but significant differences between devices in walking speed (p<0.05) could not explain the substantial PP differences between the different devices. Although all off-loading devices resulted in a significant reduction of forefoot plantar pressure, devices differed significantly in the magnitude of pressure reduction. Further research will have to reveal the level of off-loading sufficient for effective treatment of diabetic ulcers