Wei-Jun Fu

Vaporesection for managing benign prostatic hyperplasia using a 2-µm continuous-wave laser: a prospective trial with 1-year follow-up

To explore the safety and clinical efficacy of continuous‐wave laser vaporesection for the treatment of obstructive benign prostatic hyperplasia (BPH).

Nutcracker phenomenon: A new diagnostic method of multislice computed tomography angiography

Objective:  We evaluated 3‐D computed tomography angiography (3‐D CTA) in the diagnosis of the nutcracker phenomenon, and its significance in postoperative follow up.

Tissue engineering of ureteral grafts by seeding urothelial differentiated hADSCs onto biodegradable ureteral scaffolds

The study is aimed to evaluate the differentiation potential of human adipose-derived stem cells (hADSCs) into urothelial lineage, and to assess possibility of constructing ureteral grafts using the differentiated hADSCs and a novel polylactic acid (PLA)/collagen scaffolds. HADSCs were indirectly cocultured with urothelial cells in a transwell coculture system for urothelial differentiation. After 14 days coculturing, differentiation was evaluated by detecting urothelial lineage markers (cytokeratin-18 and uroplakin 2) in mRNA and protein level. Then the differentiated hADSCs were seeded onto PLA/collagen ureteral scaffolds and cultured in vitro for 1 week. The biocompatibility of the scaffolds was tested by scanning electron microscopy (SEM) and MTT analysis. At last, the cell/scafflod grafts were subcutaneously implanted into 4-week-old female athymic mice for 14 days. The results demonstrated that the hADSCs could be efficiently induced into urothelial lineage by indirect coculture. The differentiated cells seeded onto the PLA/collagen ureteral scaffolds survived up to 7 days and maintained proliferation in vitro, which indicated that the scaffolds displayed good biocompatibility. In vivo study showed that the differentiated cells in the grafts survived, formed multiple layers on the scaffolds and expressed urothelial lineage markers. In conclusion, hADSCs may serve as an alternative cell resource in cell-based tissue engineering for ureteral reconstruction. These cells could be employed to construct a model of ureteral engineering grafts and be effectively applied in vivo, which could be a new strategy on ureteral replacement with applicable potential in clinical research.

New ureteral scaffold constructed with composite poly(L-lactic acid)–collagen and urothelial cells by new centrifugal seeding system†

A tissue-engineered ureteral scaffold was constructed with composited poly L-lactic acid (PLLA)-collagen endoluminal stent and uroepithelial cells (UECs) using a new seeding system. The electrospun PLLA-collagen nanofibrous mesh was seeded efficiently with human ureteral epithelial cells using a modified centrifugal seeding device. The cellular nanofibrous mesh was then wound around a spiral endoluminal stent to form a cellular composited PLLA-collagen ureteral scaffold. The cellular ureteral scaffold was subcutaneously implanted into nude mice. Cell attachment, distribution, and viability in vitro were investigated along with the cell fate in vivo. (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that scaffolds seeded with centrifugal method had higher cellular activity than scaffolds seeded with static method (p < 0.05), and the metabolic activity per cell had no significant differences between the two methods (p > 0.05). Histologic analysis showed that the entrapped UECs remained in the scaffolds after 2 wk of implantation. The results of the study indicated that the composited PLLA-collagen endoluminal stent could serve as alternative cell carrier for tissue engineering ureter. In addition, the new modified centrifugal seeding system allowed rapid homogeneous distribution of cells onto the nanofibrous mesh, which will be useful to ureteral reconstruction.

Biodegradable urethral stents seeded with autologous urethral epithelial cells in the treatment of post-traumatic urethral stricture: a feasibility study in a rabbit model

To evaluate the adhesion and growth of rabbit urethral epithelial cells (UECs) on a biodegradable unbraided mesh urethral stent, and to assess the feasibility and effect of the cell‐seeded urethral stent for treating post‐traumatic urethral stricture (PTUS) in a rabbit model.

Comparison of a biodegradable ureteral stent versus the traditional double-J stent for the treatment of ureteral injury: an experimental study

Ureteral injury remains a major clinical problem; here we developed a biodegradable ureteral stent and compared its effectiveness with a double-J stent for treating ureteral injury. Eighteen dogs with injured ureters were subdivided into two groups. In group A, one injured ureter was treated with a biodegradable stent, whereas only end-to-end anastomosis was performed on the other side. In group B, one injured ureter was treated with a biodegradable stent, while a double-J stent was used on the other side. Intravenous urography, radioactive renography, histological examinations, scanning electron microscopy (SEM) and elemental composition analysis were performed at 40, 80 and 120 days postoperatively. Results showed that the biodegradable stent could effectively prevent hydronephrosis and hydroureter secondary to ureteral injury. Moreover all biodegradable stents gradually degraded and discharged completely in 120 days. SEM and elemental composition analysis of the surface of the double-J stent confirmed calcification at 80 days and calcific plaque at 120 days, while no signs of calcification were found in the biodegradable stent group. Histological studies found no difference between the biodegradable stented ureters and double-J stented ureters. It is concluded that the biodegradable ureteral stent was more advantageous than the double-J stent for treating ureteral injury in a canine model.

Introduction to biodegradable polylactic acid ureteral stent application for treatment of ureteral war injury

Study Type – Therapy (case series)

Photoselective laser vaporization prostatectomy for acute urinary retention in China.

PURPOSE To assess the clinical efficacy and safety of photoselective laser vaporization of the prostate (PVP) in the treatment of patients with acute urinary retention (AUR) secondary to benign prostatic hyperplasia (BPH). PATIENTS AND METHODS Forty-two patients (mean age 72 +/- 5 years, range 65-89) with AUR because of BPH were treated with a prospective trial of PVP with the potassium-titanyl-phosphate (KTP) laser. The treatment outcome was evaluated with subjective and objective tests at 1, 3, 6, and 12 months after PVP using the International Prostate Symptom Score (IPSS), disease-specific quality of life (QoL) score, postvoid residual (PVR) urine volume, and maximum urinary flow rate (Qmax). The International Index of Erectile Function questionnaire and a self-designed ejaculatory questionnaire were completed at different follow-up times to determine patient satisfaction and changes in sexual function. RESULTS After preliminary urine drainage and adequate preoperative preparation, PVP was performed and bladder outlet obstruction was effectively relieved. The mean prostate volume was 62.5 +/- 11.7 cc, and the mean residual volume with retention was 650 mL (range 240-1200 mL). Mean operative time was 28.6 +/- 5.7 minutes. Mean catheterization duration was 5.6 days (range 3-14 d). There was significant subjective improvement of symptoms and objective improvement in urinary flow rates at 12 months. The mean IPSS and QoL score decreased significantly (P < 0.05). Mean PVR volume also decreased. The mean Qmax was 16.2 +/- 4.6 mL/sec after treatment. Only two patients had recurrent urinary retention during follow-up. There were no intraoperative or postoperative adverse events. CONCLUSIONS The early clinical results suggest that the PVP is a promising safe, effective, and less-invasive treatment with minimal morbidity for patients with urine retention secondary to BPH.

A Tissue-Specific Scaffold for Tissue Engineering-Based Ureteral Reconstruction

Terminally differentiated somatic cells can rapidly change phenotypes when they are isolated from their native tissue and cultured in vitro. This problem may become a barrier to tissue engineering-based organ reconstruction, which utilizes somatic cells. The present study was designed to validate the feasibility of maintaining the urothelial cell phenotype in a tissue-specific ureteral scaffold. The tissue-specific scaffold was fabricated by blending poly (L-lactic acid) (PLLA) and ureteral extracellular matrix (UECM) using electrostatic spinning technology. PLLA was used to enhance the mechanical properties, and UECM was used to mimic the natural components of the ureter. Primary urothelial cells (UCs), derived from ureteral mucosa, were seeded onto the tissue-specific scaffold to assess cell adhesion, proliferation and phenotypes at designated time points. The results showed that UCs in the tissue-specific scaffold exhibited better proliferation compared to cells in pure PLLA or a PLLA-small intestinal submucosa (PLLA-SIS) scaffold (p<0.05). At different time points, the expression of a UC-specific marker (UroplakinⅢ) in the tissue-specific scaffold was significantly higher than its expression in pure PLLA or a PLLA-SIS scaffold (p<0.05). Therefore, the tissue-specific scaffold appears to be an ideal substrate for promoting UC survival and phenotype maintenance.

Biodegradable urethral stent in the treatment of post-traumatic urethral strictures in a war wound rabbit urethral model

To prevent terrorism during anti-terror war, we developed a reproducible animal model for the induction of a urethral stricture in a war wound rabbit, and to evaluate the feasibility and effect of using a biodegradable urethral stent in the prophylaxis and treatment of urethral strictures in a war wound (or traumatic) rabbit urethral model. The urethral stricture rabbit model was successfully performed by a self-control explosion destructor. New biodegradable urethral stents were placed in the urethras of 20 war wound (traumatic) rabbits, but no stent was used in the 8 rabbits which formed the control group. Follow-up investigation included assessment of procedure success, stent changes, urethrascopy and retrograde urethrography, and histological findings were obtained after sacrifice at 4, 6, 8 and 12 weeks after stent placement. The urethral stricture model owing to a war wound (trauma) was tested by tissue reactions and urethroscopy. The length of the urethral strictures was 5-10 mm; the coarctation of the urethral lumen was more than 50%. Biodegradable stent placement was technically successful in 20 rabbits. Urethral specimens obtained from the 4 week stent placement group showed diminished inflammatory cell infiltration and decreased thickness of the papillary projections of the epithelium. There was a strong tendency towards regression of the papillary projections and regeneration of urethral mucosa epithelium in the 8 week group. In particular, the injured urethra has recovered completely in the biodegradable stent groups compared with the control group at 12 weeks. The biodegradable urethral stent seems feasible for treating and preventing urethral strictures owing to a war wound (or traumatic) urethra. There are distinct advantages in terms of safe, effective and less-invasive treatment for the reconstruction of post-traumatic urethral strictures.