Effect of DNA on the conformational dynamics of the endonucleases I-DmoI as provided by molecular dynamics simulations.

The conformational behavior of the wild-type endonucleases I-DmoI and two of its mutants has been studied in the presence and in the absence of DNA target sequences by means of extended molecular dynamics simulations. Our results show that in the absence of DNA, the three protein forms explore a similar essential conformational space, whereas when bound to the same DNA target sequence of 25 base pairs, they diversify and restrain the subspace explored. In addition, the differences in the essential subspaces explored by the residues near the catalytic site for both the bound and unbound forms are discussed in background of the experimental protein activity.

Robotics in general surgery: personal experience in a large community hospital.

HYPOTHESIS: Robotic technology is the most advanced development of minimally invasive surgery, but there are still some unresolved issues concerning its use in a clinical setting. DESIGN: The study describes the clinical experience of the Department of General Surgery, Misericordia Hospital, Grosseto, Italy, in robot-assisted surgery using the da Vinci Surgical System. RESULTS: Between October 2000 and November 2002, 193 patients underwent a minimally invasive robotic procedure (74 men and 119 women; mean age, 55.9 years [range, 16-91 years]). A total of 207 robotic surgical operations, including abdominal, thoracic and vascular procedures, were performed; 179 were single procedures, and 14 were double (2 operations on the same patient). There were 4 conversions to open surgery and 3 to conventional laparoscopy (conversion rate, 3.6%; 7 of 193 patients). The perioperative morbidity rate was 9.3% (18 of 193 patients), and 6 patients (3.1%) required a reoperation. The postoperative mortality rate was 1.5% (3 of 193 patients). CONCLUSIONS: Our preliminary experience at a large community hospital suggests that robotic surgery is feasible in a clinical setting. Its daily use is safe and easily managed, and it expands the applications of minimally invasive surgery. However, the best indications still have to be defined, and the cost-benefit ratio must be evaluated. This report could serve as a basis for a future prospective, randomized trial.