Differentiation and proliferation of spermatogonial stem cells using a three-dimensional decellularized testicular scaffold: a new method to study the testicular microenvironment in vitro

International Urology and Nephrology - Successful in vitro transplantation of spermatogonial stem cells (SSCs) demands effective culture systems for SSCs proliferation and differentiation. Natural...     

The application of tissue-engineered preputial matrix and fibrin sealant for urethral reconstruction in rabbit model

Background

To introduce the role of fibrin sealant and preputial acellular matrix (PAM) as a new source of inert collagen matrix for urethral reconstruction.

Methods

A ventral urethral segmental defect was created in 24 male rabbits divided into four groups. In group 1 (G1), urethrotomy was closed in layers. In group 2 (G2), closure was followed by applying fibrin sealant. In groups 3 (G3) and 4 (G4), urethroplasty was performed with a patch graft of PAM, and in G4, fibrin sealant was also applied. Serial urethrography was performed before and after the operation. Then, the animals were euthanized, and their urethra was excised 1, 3, and 9 months postoperatively for further electron microscopic examination, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) technique, and immunohistochemical (IHC) staining with CD34, CD31, desmin, SMA, and α-actin.

Results

In G1 and G2, the fistula repair failed in all the time points. In G3 and G4, serial urethrography confirmed the maintenance of a wide urethral caliber without signs of strictures or extravasations. Satisfactory vascularity was observed in G3 and G4 during the whole study, which was more significant in G4 after 9 months of follow-up. The presence of a complete transitional cell layer was confirmed over the graft in G3 and G4 in all time points. IHC staining confirmed the effectiveness of fistula repair in G3 and G4, 3 months postoperatively.

Conclusion

This rabbit model showed that PAM combined with fibrin sealant may herald a reliable option for repairing segmental urethral defects.     

Combination of calcium hydroxyapatite and autologous blood for endoscopic treatment of vesicoureteral reflux in children

Objective

To report the results of endoscopic correction of vesicoureteral reflux (VUR) with concomitant injection of pure calcium hydroxyapatite (CaHA) and autologous blood.

Patients and methods

Records of patients who underwent endoscopic correction of VUR using concomitant injection of CaHA and autologous blood from 2008 through 2010 were retrospectively reviewed. Data regarding patients’ demographics, preoperative VUR grades, febrile urinary tract infections, complications of procedure, postoperative VUR grades and cure rates were collected. Voiding cystourethrography was performed 3 months postoperatively.

Results

Total number of 23 children (9 girls and 14 boys) with 40 refluxing ureters were included. The mean age of children was 1.9 ± 0.97 (SD) years. Reflux grades were II to IV in 14, 11 and 15 renal refluxing units (RRUs), respectively. The mean follow-up period was 44 months. VUR was successfully treated in 87.5 % of RRUs after three injections. Significant statistical difference was found between VUR grades before and after the first, second and third injections (p < 0.001, p = 0.001 and p = 0.011, respectively). Moreover, there was a significant difference between primary reflux grade and treatment success (p = 0.031). Febrile UTI was resolved in 85 % of patients (17 of 20 patients with febrile UTI) after endoscopic treatment which shows significant improvement (p < 0.001). The procedure was uneventful in all patients, and no obstruction was reported during the follow-up period.

Conclusion

Concomitant injection of pure CaHA without any additives (hyaluronic acid, etc.) and autologous blood can be an effective, repeatable and cost-benefit approach for the management of children suffering VUR with a success rate of 87.5 % after three injections.

     

Decellularized human fetal intestine as a bioscaffold for regeneration of the rabbit bladder submucosa

Purpose

We aim to report a method to create a natural acellular scaffold from human fetal small intestine for augmentation cystoplasty in rabbits.

Evolution of endoscopic management of ectopic ureterocele: a new approach

PURPOSE: We report the evolution of endoscopic treatment of ectopic ureteroceles from the unroofing technique to a novel approach using concomitant ureterocele double puncture and intraureterocele fulguration. We also compare the results of different endoscopic modalities at a single center. MATERIALS AND METHODS: We reviewed the records of 46 children with ectopic ureteroceles who were treated endoscopically between 1995 and 2005. The patients were divided into 2 main groups. Group 1 included 17 patients who underwent common endoscopic treatments, including ureterocele incision (4 patients), single ureterocele puncture (4), and single puncture with insertion of a Double-J stent (9). Group 2 included 29 children who underwent ureterocele double puncture and fulguration of the anterior and posterior walls of the collapsed ureterocele after insertion of a Double-J stent into both punctured sites. We also managed concomitant vesicoureteral reflux by endoscopic injection of tricalcium phosphate ceramic into the subureteral region. RESULTS: Total success rates in group 1 were 0%, 25% and 33% in patients who underwent ureterocele incision, single ureterocele puncture and single puncture with insertion of a stent, respectively. Total success rate in group 2 was 90% (p<0.05). New onset vesicoureteral reflux developed in 8 patients (47%) in group 1, of which 6 were in ureterocele moieties, and in 8 patients (28%) in group 2, with none in a ureterocele moiety (p<0.01). A total of 13 patients (76%) in group 1 required open surgical intervention, compared to 3 (10%) in group 2 (p<0.05). CONCLUSIONS: This new endoscopic approach is highly effective in the treatment of children with ectopic ureteroceles.     

Infantile bladder rupture during voiding cystourethrography

Bladder rupture is rare during infancy and most of reported cases had urethral obstruction or neurogenic bladder. We report two cases of infantile bladder rupture during voiding cystourethrography (VCUG). This report reinforces the criteria for proper VCUG imaging procedure. Consideration of expected bladder volume for body weight, and close monitoring of bladder pressure and injection speed could prevent such complications.