ABSTRACT
The eukaryotic RNA polymerases Pol I, Pol II, and Pol III are the central multiprotein machines that synthesize ribosomal, messenger, and transfer RNA, respectively. Here we provide a catalog of available structural information for these three enzymes. Most structural data have been accumulated for Pol II and its functional complexes. These studies have provided insights into many aspects of the transcription mechanism, including initiation at promoter DNA, elongation of the mRNA chain, tunability of the polymerase active site, which supports RNA synthesis and cleavage, and the response of Pol II to DNA lesions. Detailed structural studies of Pol I and Pol III were reported recently and showed that the active center region and core enzymes are similar to Pol II and that strong structural differences on the surfaces account for gene class-specific functions.
Subject(s)
DNA-Directed RNA Polymerases , Models, Chemical , Models, Genetic , RNA/biosynthesis , RNA/chemistry , Transcription, Genetic/genetics , Animals , DNA-Directed RNA Polymerases/chemistry , DNA-Directed RNA Polymerases/genetics , DNA-Directed RNA Polymerases/ultrastructure , Enzyme Activation , Humans , Models, Molecular , RNA/geneticsABSTRACT
We reviewed our experience with 17 cases of posterior urethral disruption due to traumatic pelvic injuries. In all cases, a suprapubic cystostomy was performed at first. For blunt injuries, urethroplasty was delayed for 6 months in average. For most of the penetrating injuries (3/4), we performed immediate debridement and primary repair. Resulting bulbous or membranous strictures less than 3 cm long were treated with one-stage perineal excision-reanastomosis urethroplasty. Membranous strictures longer than 3 cm were managed with a combined transpubic-perineal repair, while bulbous defects longer than 3 cm were treated with a scrotal pedicled island flap. The overall restricture rate was 25%. Those having had initial repeated urethrotomies displayed a 100% restenosis rate. Incontinence rate was 12.5% Erectile dysfunction occurring in 42% of our patients is a sequela of the pelvic injury and was found to be directly related postoperatively to its presence at the time of surgery.
Subject(s)
Pelvis/injuries , Urethra/injuries , Urethra/surgery , Accidents, Traffic , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Urethral Stricture/surgery , Wounds, Gunshot/complications , Wounds, Nonpenetrating/complicationsABSTRACT
During the last 4 years, 12 patients had an implantation of the AMS Ultrex2 penile prosthesis : 4 of these patients were impotent after a cystoprostatectomy, 4 patients had vascular insufficiency, 2 patients had psychogenic impotency, one patient was diabetic and one patient had a spinal cord injury. The complication rate was low (16%): one patient necessitated a surgical revision of the prosthesis after disconnection of the tubulure. A second patient had a urethral stenosis treated by dilation. The degree of satisfaction of both patient and partner was satisfactory.
Subject(s)
Erectile Dysfunction/surgery , Penile Prosthesis/standards , Adult , Aged , Equipment Design , Erectile Dysfunction/etiology , Humans , Male , Middle Aged , Patient Satisfaction , Penile Prosthesis/adverse effects , Penile Prosthesis/classification , Reoperation , Treatment OutcomeABSTRACT
A total of 1500 patients underwent treatment with the Wolf Piezolith 2300 extracorporeal shockwave lithotripter for renal, ureteral, and bladder stones. Follow-up data were available at 3 months for 1435 patients. At that time, the overall stone-free rate was 82.7%: 82.4% for patients with renal stones, 81.0% for those with ureteral stones, and 100% for those with bladder stones. The overall success rate was 92.3%: 93.8% for patients with renal stones, 87.1% for those with ureteral stones, and 100% for those with bladder stones. The auxiliary treatment rate was 14.9%, and the retreatment rate was 53%. The effectiveness quotient was 49.2%. The Wolf Piezolith 2300 is an effective treatment for most stones smaller than 30 mm.
Subject(s)
Kidney Calculi/therapy , Lithotripsy/instrumentation , Ureteral Calculi/therapy , Urinary Bladder Calculi/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Follow-Up Studies , France , Hospitals , Humans , Male , Middle AgedABSTRACT
This study describes the results of 50 consecutive cases of varicocelectomy by the inguinal approach. The testicle is delivered through a small inguinal incision, and all external spermatic and gubernacular veins are ligated. The testis is returned to the scrotum and the spermatic cord is dissected under optical magnification. The testicular artery, the lymphatics and the vas deferens are identified and preserved. All internal spermatic veins are ligated. 94 varicocelectomies were performed in 50 men. Follow-up period extended from 12 months to 24 months. No hydroceles, no clinical recurrences and no wound infection were found. One scrotal hematoma occurred and resolved progressively. Preoperative and postoperative semen analysis were obtained. The changes in sperm count mean value (million/cc) (20 to 28.6) (p < 0.005), per cent normal forms (42.9 to 52.1%) (p < 0.005) and per cent motility (31.5 to 39.2%) (p < 0.005) were significant. The pregnancy rate was 10 of 21 couples available for follow-up (47.6%). This technique results in a significant decrease in the incidence of hydrocele formation, testicular artery injury and varicocele clinical recurrence.
