Two-Photon Polymerized Shape Memory Microfibers: A New Mechanical Characterization Method in Liquid.

Two-photon polymerization (TPP) has been widely used to create 3D micro- and nanoscale scaffolds for biological and mechanobiological studies, which often require the mechanical characterization of the TPP fabricated structures. To satisfy physiological requirements, most of the mechanical characterizations need to be conducted in liquid. However, previous characterizations of TPP fabricated structures were all conducted in air due to the limitation of conventional micro- and nanoscale mechanical testing methods. In this study, we report a new experimental method for testing the mechanical properties of TPP-printed microfibers in liquid. The experiments show that the mechanical behaviors of the microfibers tested in liquid are significantly different from those tested in air. By controlling the TPP writing parameters, the mechanical properties of the microfibers can be tailored over a wide range to meet a variety of mechanobiology applications. In addition, it is found that, in water, the plasticly deformed microfibers can return to their pre-deformed shape after tensile strain is released. The shape recovery time is dependent on the size of microfibers. The experimental method represents a significant advancement in mechanical testing of TPP fabricated structures and may help release the full potential of TPP fabricated 3D tissue scaffold for mechanobiological studies.

[Intraoperative complications and morbidity of laparoscopic radical prostatectomy (LRP) during the learning curve]. / Complicaciones intraoperatorias y morbilidad de la prostatectomía radical laparoscópica (PRL) durante el periodo de aprendizaje.

OBJECTIVES: To analyze the complications and morbidity during our learning curve of laparoscopic radical prostatectomy (LRP) and compare them with other published series. METHODS: We review the 25 first laparoscopic radical prostatectomies performed in our department, evaluating the operative technique and other features such as surgical time, blood loss, complications and conversion to open surgery. We also evaluate morbidity, postoperative hospital stay, and functional features such as potency and continence. RESULTS: LRP was completed in 22 patients. Overall intraoperative complication rate was 32%. 3 cases were converted to open surgery due to technical difficulties or intraoperative complications. We had complications in 4 patients, that were not severe (bladder injury 2 cases, and epigastric artery injury another 2) and where solved without difficulties during the operation. The most severe intraoperative complication was related to the anesthesia procedure at the time of extubation of a patient who required tracheotomy. There were no severe postoperative complications, being leakage from the anastomosis the most common (7 cases). All of them were managed conservatively, although this resulted in a mean hospital stay of 10.8 days. 2 patients required endoscopic procedures in the immediate postoperative time for bladder catheter repositioning. All patients suffered erectile dysfunction and the continence rate at 3 months was 77.2%. CONCLUSIONS: Although LRP is a long operation and difficult during the learning curve, its complication rate is acceptable because they are not severe and can be managed in a relatively easy way.

[Ureteroscopy in the follow-up protocol for upper urinary tract urothelial tumors treated endoscopically]. / La ureteroscopia en el protocolo del seguimiento del tumor del urotelio superior tratado por via endoscópica.

OBJECTIVES: To evaluate the role of ureteroscopy (rigid and flexible) in the follow-up protocol for transitional cell tumors treated conservatively in our department by endourological procedures, and to review the articles on this topic available in the literature. METHODS: From February 1997 to June 2003, 10 patients (12 renal units) with upper urinary tract urothelial tumor treated conservatively by endourological procedures were followed by cytology, cystoscopy, retrograde ureteropyelography, and ureteroscopy (rigid and flexible), quarterly during the first year, semi-annually during the second year, and yearly thereafter in order to detect tumor recurrence. RESULTS: Mean follow-up was 31.9 months (R 14-65). Two patients died: one because of a previous metacronous bladder tumor and the other after distant progression. One patient was lost to followup. A total of 42 ureteroscopies were performed (31 flexible and 11 rigid). Flexible ureteroscopy was performed in 6 patients and rigid ureteroscopy in three; neither was feasible in one patient so that follow-up was done by cytology, cystoscopy and urography. Tumor recurrence was detected in 2 patients but ureteroscopy did not inform about tumor stage. Flexible ureteroscopy failed in another patient in which rigid ureteroscopy was feasible. Although this latter was technically easier to perform, procedure discomfort was worse. CONCLUSIONS: The follow-up of transitional cell tumors of the upper urinary tract should be very strict because of the high risk of tumor relapse. Ureteroscopy, mainly flexible, is standing out as the most effective procedure to watch these tumors.

[Laparoscopic pyeloplasty. Our experience]. / Pieloplastia laparoscópica. Nuestra experiencia.

OBJECTIVES: To report our experience with laparoscopic pyeloplasty in the treatment of pyeloureteral junction obstruction. METHODS: Between August 2001 and August 2004 14 patients with the diagnosis of pyeloureteral junction obstruction underwent laparoscopic repair. Seven cases had the obstruction on the left side and the other seven on the right side. We describe the technique of laparoscopic dismembered Anderson-Hynes type pyeloplasty, performed to 12 patients in our series. The remainder 2 patients underwent Foley's Y-V plasty and the Fenger's technique. RESULTS: Mean operative time was 199.7 minutes (r: 126-290). There were not intraoperative complications. Mean hospital stay was 4.63 days (r: 3-9). One case of double J catheter obstruction can be cited as late postoperative complication. Only one of the 14 cases suffered a recurrence of the stenosis after double J catheter retrieval. CONCLUSIONS: Laparoscopic pyeloplasty has become the operation of choice in cases of hydronephrosis secondary to crossing vessel, when there is great pyelic dilation, and for the treatment of failures of previous endopyelotomy.

[Radical cystectomy. Bladder substitution (in women)]. / Cistectomía radical. Sustitución vesical (en mujer).

OBJECTIVES: To report our experience with a series of 10 patients undergoing radical cystectomy with bladder substitution. We were supported by a better knowledge of the female continence anatomical mechanisms and the demonstration of the oncological viability of the urethral remnant. METHODS: From 1994 to 2002 10 women underwent radical cystectomy with bladder substitution by means of a modified anterior pelvic exanteration; technical modifications to achieve continence preservation are based on: preservation of the distal 2/3 of urethra, pubourethral ligaments and endopelvic fascia, and limitation of lateral vaginal dissection to avoid damage to the striated sphincter innervation. To avoid the neocystocele effect the vagina is fixed to the uterosacral ligaments and to the sacral promontory. RESULTS: Bladder capacity is 332.9 +/- 35.6 ml with a flow of 17.7 ml/sec. Complete continence wax achieved in 8 patients, the remainder 2 present grade II urinary stress incontinence. All of them empty their neobladder satisfactorily; only one patient needed a bladder re-education program. One bladder fistula and diarrhoea in one patient are the complications to be highlighted. CONCLUSIONS: The results obtained with orthotopic neobladder in females, achieving a high satisfaction level and quality of life, stimulate us to continue with this technique.