Mechanisms in practice: A methodological approach.

In this paper, we offer a minimal characterization of the concept of mechanism in biomedicine, according to which a mechanism is a theoretically described causal pathway. We argue that this conception can be drawn from scientific practice, as illustrated by how a central biological and biomedical mechanism, the mechanism of apoptosis, was first identified and characterized. We will use the example of cytological and biochemical theoretical descriptions of the mechanism of apoptosis to draw lessons about the meaning of the concept of mechanism in biomedical contexts and to contrast our preferred account of mechanism with some prominent accounts within the philosophical literature. The main outcome of our discussion will be that commitment to mechanism is first and foremost a methodological stance.

Comparison Between Ambulatory and Conventional Urodynamics of the Modified Orthotopic Hautmann Neobladder / 대한배뇨장애요실금학회지

PURPOSE: The aim of the present study was to determine the diagnostic accuracy of conventional and ambulatory urodynamic studies (UDS) in estimating neobladder function. METHODS: We evaluated 32 patients who underwent radical cystectomy and orthotopic Hautmann W neobladder with Abol-Enein-Ghoneim uretero-intestinal anastomosis for bladder cancer. The patients were initially examined by using both conventional and ambulatory UDS. RESULTS: Conventional UDS detected a very high mean intravesical pressure at maximum capacity (53.7+/-17.5 cm H2O). By contrast, the mean intravesical pressure detected by using ambulatory UDS (which reflects the dominant pattern of pressure variation during filling) was significantly lower (34.4+/-5.2 cm H2O, P<0.001). The comparison between intravesical pressure at half of maximum capacity in conventional UDS and the mean value in ambulatory UDS did not show significant difference (P=0.152). The mean voided volume in conventional UDS was greater than both the mean voided volume (P<0.001) and the mean maximum voided volume in ambulatory UDS (P=0.001). However, this difference did not affect the postvoid residual urine volume measured in both studies (P=0.207). Moreover, incontinence episodes recorded in ambulatory UDS were more frequent but not statistically significantly different from those recorded in conventional UDS (P=0.332). CONCLUSIONS: The estimation of neobladder function by means of ambulatory UDS seems to provide interesting research data for the mode of lower urinary tract function in patients with orthotopic substitution after radical cystectomy. The great high value in ambulatory UDS, in cases in which conventional UDS had failed, is due to the exposure of daily and nocturnal incontinence episodes, confirming our patients' complaints.

Dermal scarification versus intramuscular diclofenac sodium injection for the treatment of renal colic: a prospective randomized clinical trial.

The aim of the study is to determine whether dermal scarification is equally effective for treating acute renal colic compared to diclofenac sodium intramuscular therapy. A prospective, randomized controlled study was conducted with methodologic rigor based on CONSORT criteria. A total of 291 patients, aged ≥ 18 years, suffering from acute renal colic were included in this trial and randomly assigned in two groups. Patients in the first group (A) received endodermal injection (dermal scarification) of 1 ml normal saline at the area of intensity of pain. The second group (B) received 75 mg diclofenac sodium by intramuscular injection. The success of each method defined the primary end point. Pain intensity before and after treatment was assessed using a visual analog scale. The time onset and the duration of analgesia were also recorded. There was no significant difference between the two groups regarding hematuria (p = 0.158), stone identification at KUB (p = 0.751) and mean pain intensity (p = 0.609) before treatment initiation. The method was successful in 75.5 % of patients in group A and 74.3 % of patients in group B (p = 0.812). Mean pain reduction was comparable, 5.65 ± 3.05 in group A and 5.34 ± 2.99 in group B (p = 0.379), with dermal scarification eliciting its effect considerably faster, whereas the duration of analgesia was longer in the diclofenac group (p < 0.05). In conclusion, dermal scarification could constitute an alternative method for treating renal colic as it is equally effective compared to the standard treatment of diclofenac sodium.

High patient satisfaction after inflatable penile prostheses implantation correlates with female partner satisfaction.

INTRODUCTION: Patient and female partner satisfaction after implantation of an inflatable penile prosthesis (IPP) assessed by objective means, and the correlation between the partners, is important for determining postoperative sexual life. AIM: The primary goal was to evaluate patients' erectile function and patients' and their partners' satisfaction after IPP implantation. A secondary aim was to investigate potential determinative factors of satisfaction according to device characteristics, demographics, and cause of erectile dysfunction (ED). METHODS: Ninety patients, who underwent IPP implantation as an alternative to refractory or undesirable medical treatment for ED, were evaluated. Patients who could not or refused to participate, or were out of a relationship, were excluded. The 69 remaining patients were evaluated for their pre- and postoperative erectile function and posttreatment satisfaction for themselves and their partners. MAIN OUTCOME MEASURES: Preoperative and postoperative scores on the International Index of Erectile Function Questionnaire-five items (IIEF-5) were compared. The Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) was given to males and their female partners. Patient demographics, etiology of ED, and implant characteristics were correlated also with patients' EDITS scores. RESULTS: Mean IIEF-5 scores demonstrated a significant improvement after IPP implantation: from 8.88±3.75 to 20.97±4.37 (P<0.001). The mean patients' EDITS score was 75.48±20.54, whereas mean female partners' score was 70.00±22.92, highlighting high posttreatment satisfaction for both. Regression analysis suggested a direct linear correlation of satisfaction between the sexual partners as a degree of satisfaction. There were no statistically significant differences according to level of education or implant characteristics. Concerning the etiology of ED, no conclusions could be made. CONCLUSIONS: Overcoming previous limitations in determining post-IPP implantation satisfaction, our study reiterates high rates of patient and partner satisfaction. Of particular note, patient satisfaction appears independent of prosthesis type and cylinder length.

Papillary cystadenoma of epididymis: Is there a need for further investigation in unilateral cases?

INTRODUCTION: The presence of a mass in the epididymis is not a common entity. The papillary cystadenoma of epididymis is a benign tumor which may occur sporadically or as a characteristic of von Hippel-Lindau disease. PRESENTATION OF CASE: We present a case of a 27-year-old man with a right scrotal mass who was treated with surgical excision. Histopathological examination revealed a clear cell epididymal papillary cystadenoma. A computed tomography scan that was performed later showed no other abnormality or any signs of von Hippel-Lindau disease. DISCUSSION: In this report, a case of a young man suffering from this rare tumor is discussed, focusing on the need of further evaluation in order to determinate if it occurs as a feature of VHL disease or as a sporadic form. CONCLUSION: In unilateral cases of papillary cystadenoma of epididymis such as our patient's, literature advocates that no further examinations and expensive genetic testing is required.

Unilateral urinothorax can occur contralateral to the affected kidney.

Urinothorax is a rare cause of transudative pleural effusion with biochemical characteristics of urine, usually secondary to obstructive uropathy. Urine usually moves into the pleural space from the retroperitoneal or peritoneal space via diaphragmatic lymphatics or an anatomical diaphragm defect. A total of approximately 70 cases have been previously described in the literature, and in the vast majority of cases urinothorax is unilateral and ipsilateral to the side of obstructive uropathy, trauma or malignancy. This report describes a rare case of unilateral urinothorax occurring contralateral to the side of obstruction.

Our experience with salvage genitourinary fistulae repair: technique and outcomes.

OBJECTIVES: The objectives are to present the long-term results of vaginal reconstructive operations using the labial fat pad flap (Martius flap) interposition. PATIENTS AND METHODS: Eight women, 27-65 years old (mean 40), suffering from urinary fistulae (five urethrovaginal and three vesicovaginal) who failed primary repair underwent salvage vaginal reconstruction for damaged urethra or bladder. Urethral or bladder and vaginal defect was closed and a Martius fat flap was interposed between urethra or bladder and vaginal wall flap to secure a watertight separation of the structures. A Martius flap was also used successfully for salvage vaginal reconstruction in three more women, two with extensive injury of their urethra and bladder neck and one with vaginal leakage, after a rectosigmoid neobladder diversion following cystectomy. RESULTS: The repair was successful in all eight patients with urinary fistulae and in the one with rectovaginal leakage. The patient with the traumatically injured urethra and bladder neck developed an anastomotic stricture treated with urethral dilatations and internal urethrotomy. The older one developed a vesicovaginal fistula due to bladder neck closure, and this was repaired with a second transvaginal closure. CONCLUSION: Martius labial fat flap is an easy to prepare, well-vascularized tissue that can be most helpful in achieving a long-lasting favorable outcome in vaginal reconstructive surgery.

Dorsal on-lay preputial graft urethroplasty for anterior urethra strictures repair.

OBJECTIVES: To report the long-term results and evaluate the effectiveness of the dorsal on-lay preputial graft urethroplasty in patients suffering from anterior urethra strictures. METHODS: A total of 21 male patients, mean age 46.3 years (range 17-67), with anterior urethral strictures, underwent the dorsal on-lay preputial graft urethroplasty during the last 8 years, from October 1997 to September 2005. Strictures were located in bulbar urethra in 16 patients and in penile urethra in the remaining 5. The aetiology the stricture was traumatic injury of the anterior urethra in 12 patients and iatrogenic in 9 patients. A direct vision dorsal urethrotomy and the insertion of an urethral Foley catheter right before the procedure, facilitated the corpus spongiosum dissection and the preparation for urethroplasty. A voiding cystogram was performed on the day of urethral catheter removal to exclude extravasation and estimate the postoperative result. RESULTS: Mean follow-up time has been 49.9 months (range 6-95) and the outcome was favourable in 15 patients (71.43%). There were 3 recurrences in penile urethra strictures managed conservatively and three in bulbar urethroplasties, treated with internal urethrotomy followed by urethral dilatations. CONCLUSION: Our results indicate that dorsal on-lay urethroplasty using preputial graft is an easy to learn and perform procedure, and offers the patient durable results with rather minimal complications.