Objective To investigate the biocompatibility of acellular urinary bladder submucosa (AUBS). Methods The acellular collagen matrix of human urinary bladder submucosa was developed using freeze-thawed enzymatic treatment and freeze-drying technique. Human oral keratinocytes were cultured and seeded on AUBS at a density of 2×106/ml in vitro.The proliferation of the cells were observed. Pockets were created in the abdominal muscle wall of 18 SD rats. AUBS in size 1 cm×1 cm was implanted into the pocket. The grafts were observed by light microscope 3, 6, 10, 14, 21 and 28 days after operation. Results AUBSmainly consisted of collagen fibers with a three-dimensional network structure. After the oral keratinocytes were seeded, continous oral epithelium layer was formed on the surface of AUBS after 10 days in vitro. Histological observation of the grafted AUBS showed progressive cell infiltration at 6 days. New capillaries formed at 14 days. The collagen fibers arranged regularly at 28 days after implantation. Conclusion Freeze-dried AUBS may be used as a suitable scaffold for tissue regeneration, which can induce cell proliferation both in vivo and in vitro and has good biocompatibilty.
Objective To investigate the feasibil ity of establ ishment of physiological micturition reflex arc by simultaneously reconstructing the sensory and the motorial nerve of atonic bladder after spinal cord injury. Methods Eight 1-year-old Beegle male canine were selected, weighing 7-12 kg. The left side was the experimental side, while the right side wasthe control side. Epidural microanastomosis of vertebral canal of the left L7 ventral root to S2 ventral root and L7 dorsal root to S2 dorsal root was performed to reconstruct the sensory and the motorial function of atomic bladder. The right side was used as a control without treatment. The new motor-to-motor, and sensory-to-sensory physiological bladder reflex pathway were establ ished after 12 months of axonal regeneration. Then S1-4 segmental spinal cord was destroyed for preparation of complete paraplegia. The electrophysiological examination and the bladder pressure were detected before and after paraplegia. The canine micturition was observed for 3 months after paraplegia. Nurohistological observation was performed after canine sacrifice. Results Of 8 canine, 7 canine survived. After paraplegia, canines displayed urinary incontinence and frequent micturition at first, nocturnal continence was achieved gradually without frequent micturition after 1 month. Urinary infection at different degrees occurred in 3 canines and was controlled after Norfloxacin was administered orally. The bladder pressure increased to (1.00 ± 0.13) kPa, (0.90 ± 0.12) kPa after trains of stimulation (300 mV, 0.3 ms, 20 Hz, 5 seconds) of S2 dorsal root at the experimental side before and after paraplegia respectively, showing no significant difference (P gt; 0.05). It increased to (1.90 ± 0.10) kPa after the same train of stimulation of S2 dorsal root at control side. There was significant difference between the experimental side and the control side (P lt; 0.01). Single stimulation (300 mV, 0.3 ms) of the S2 dorsal root at the experimental side resulted in evoked potentials recorded from the left S2 ventral root before and after paraplegia. Before and after paraplegia, the ampl itudes of the evoked potentials were (0.68 ± 0.11) mV and (0.60 ± 0.08) mV respectively, showing no significant difference (P gt; 0.05). It was (1.21 ± 0.13) mV while stimulating at the control side. There was significant difference between the experimental side and the control side (P lt; 0.01). Neurofibra of L7 dorsal and ventral root grew into S2 dorsal and ventral root on tissue sl ice under l ight microscope. Conclusion Reconstruction of the bladder physiological micturition reflex arc is feasible by anastomosis of sacral dorsal and ventral root below injured spinal plane with the suprasacral survival dorsal and ventral root above the plane respectively for restoration of atonic bladder after spinal cord injury.
Objective To evaluate the cytocompatibility of collagenmembraneswith transitional cells of rabbit in vitro and to discuss the possibility of the collagen membranes as urologic tissue engineering scaffolds. Methods Primary cultured transitional cells isolated from New Zealand rabbits were implantedon collagen membranes at 1×105 cells/cm2. The changes of cell adhering were observed by inverted microscope and scanning electron microscope 2, 12 and 24hours later. The experiment was divided into 4 groups: non-cell group (black control) culture medium group(negative control), extract medium from Polyvinyl chloride group(positive control) and extract medium from collagen membranes group(experimental group). The cells of generations 2 to 4 were implanted in 96-hole-plank at 1×104 cells every hole. And every group had 5 holes. Then absorption coefficient were detected at the wave length of 490 nm by MTT assay. Then the cytotoxicity and cytocompatibility were evaluated by comparison of the numbers of absorptioncoefficient.Results The bladder transitional cells began to adhere to the collagen membrane 2 hours after implanting, and the number of the adhered cells increased with time.The actual absorption coefficient of experimental groups was 0.590±0.024,1.065±0.040 and 1.129±0.074 after 24, 72 and 120 hours. The actual absorption coefficient of negative control group was 0.639±0.068,1.022±0.044 and 1.087±0.111. The actual absorption coefficient of positive control group was 0.302±0.029,0.653±0.083 and 0.694±0.031. There was significantdifference between the experimental group and positive control (Plt;0.01), and no significant difference between the experimental group and negative control(Pgt;0.05).Conclusion Collagen membrane has good cytocompatibility withtransitional cells and no cytotoxity. It can be used as scaffolds of urologic tissue engineering.
Twenty cases of hypospadiasundergone urethro-plasty with blad-der mucosa and correction of cordein one stage surgery are reported.Sixteen of 20 cases had satisfactoryresults .Two cases with structureof anastomosis have been improvedby urethral dilatation and the othertwo cases complicated with urethral-cutaneous fistula have gradually heal-ed with prolonged diversion of cysto- tomy. The indication and techniqueof this surgery are discussed indetail.
Twenty - three cases of hypospadiaswere treated by primary cystomucoso - ure-throplasty。Twenty cases had the success inthe first operation with the success rate of86.9%。The external urethral orifice was re-constructed to the coronary groove in 17 cas-es ,and to the glans in 6 cases。The early re-sults were satisfactory。This operative tech-nique had the advantages of convenient forobtaining the materials, reasonable physiolog-ical needs, high success rate, satisfactory ex-ternal feature, and useful in various type of hypospadias.
