BACKGROUND:The dysfunction of bladder function caused by spinal cord injury is a difficult point in clinical treatment and a hot spot in research.Repairing the injured spinal cord and remodeling the bladder micturition reflex pathway are the fundamental treatment methods. OBJECTIVE:To summarize the reconstruction of the bladder innervation pathway after spinal cord transection injury and its related influencing factors. METHODS:The relevant literature concerning the reconstruction of bladder micturition reflex,neurogenic bladder and urinary reflex and spinal cord repair was retrieved on CNKI,WanFang Data,PubMed and Web of Science.Chinese and English search terms were"neurogenic bladder;spinal cord injury;micturition reflex;spinal cord repair". RESULTS AND CONCLUSION:In the process of reconstructing the bladder micturition reflex,there are many factors involved,including the repair and reconstruction of the injured spinal cord,the remodeling of micturition center,the changes of bladder tissue and substances and hormones in and out of the body.In this process,there are mainly the following problems:(1)As a complex process,there are many sites involved in the reconstruction of the micturition reflex,so the main sites of action can be selected for in-depth study,so as to break through the doubts existing in the reconstruction of the micturition reflex pathway.(2)The mechanism of the normal micturition reflex is complex.After spinal cord transection injury,whether the central nucleus mass controlling or participating in the micturition reflex is compensated and the corresponding compensatory mechanism needs to be further investigated.(3)Information communication between the center and the bladder is interrupted after spinal cord transection injury.Whether there is a direct information connection between the center and the bladder remains to be further investigated.(4)The relationship between reconstructing micturition reflex and body fluid after spinal cord transection injury needs further study.In the reconstruction of the bladder micturition reflex,the key treatment is to promote spinal cord repair,nerve reflex reconstruction,substance metabolism and bladder tissue structure adjustment through intervention.Chinese medicine and Western medicine have their methods.

BACKGROUND:Numerous clinical and basic studies have shown that electroacupuncture can improve the function of neurogenic bladder after suprasacral spinal cord injury. OBJECTIVE:To observe the effects of electroacupuncture on bladder function and connective tissue growth factor expression in rats with suprasacral spinal cord injury. METHODS:Forty-eight female Sprague-Dawley rats were randomly divided into four groups(n=12 per group):the blank group did not receive any treatment;the sham-operated group only exposed the T8 subvertebral spinal cord;in the model group established,a T8 subvertebral spinal cord transection injury model was established;in the electroacupuncture group,the T8 subvertebral spinal cord transection injury model was established,and electroacupuncture intervention at Ciliao(BL32),Zhongji(RN03)and Sanyinjiao(SP06)was given at 19 days after modeling,20 minutes once a day,for 10 continuous days.After the intervention,the relevant indicators were detected. RESULTS AND CONCLUSION:Urodynamics:Compared with the blank group,the leakage point pressure,maximum bladder capacity and maximum bladder pressure of rats in the model group increased(P<0.05).Compared with the model group,the leakage point pressure,maximum bladder capacity and maximum bladder pressure of rats in the electroacupuncture group decreased(P<0.05).Hematoxylin-eosin staining:Compared with the blank group,the bladder epithelial cells in the model group were arranged in a disordered manner,the lamina propria was destroyed,the detrusor muscle bundles were hypertrophied,the muscle fibers were arranged in a disordered manner,and the tissue edema was obvious.Compared with the model group,the bladder epithelial cells in the electroacupuncture group were arranged in a regular and orderly manner,and the degree of bladder fibrosis and tissue edema was relatively reduced.Masson staining:The degree of bladder detrusor muscle fibrosis was severe in the model group and it was lighter in the electroacupuncture group than in the model group.Transmission electron microscopy:Mitochondria in the bladder tissue in the model group were swollen and vacuolated,the morphology of the detrusor muscle was twisted and distorted,and the muscle gap was widened.Compared with the model group,mitochondria in the electroacupuncture group had a slightly clearer contour and were less vacuolated,and the muscle gap was narrowed.Western blot detection:The protein expression of connective tissue growth factor in the detrusor muscle of the bladder was elevated in the model group compared with the blank group(P<0.05).Compared with the model group,the protein expression of connective tissue growth factor in the bladder detrusor muscle was decreased in the electroacupuncture group(P<0.05).To conclude,electroacupuncture at Ciliao(BL32),Zhongji(RN03)and Sanyinjiao(SP06)acupoints can improve the morphology,structure and function of the bladder in rats with suprasacral spinal cord injury,and the mechanism of action may be related to the down-regulation of connective tissue growth factor protein expression in the detrusor muscle.

Objective: To evaluate the bone repair effect of 3D-printed magnesium (Mg)-loaded polycaprolactone (PCL) scaffolds in a rat skull defect model. Methods: PCL scaffolds mixed with Mg microparticles were prepared by using 3D printing technology, as were pure PCL scaffolds. The surface morphologies of the two scaffolds were observed by scanning electron microscopy (SEM), and the surface elemental composition was analyzed via energy dispersive spectroscopy (EDS). The physical properties of the scaffolds were characterized through contact angle measurements and an electronic universal testing machine. This study has been reviewed and approved by the Ethics Committee. A critical size defect model was established in the skull of 15 Sprague-Dawley (SD) rats, which were divided into the PCL group, PCL-Mg group, and untreated group, with 5 rats in each group. Micro-CT scanning was performed to detect and analyze skull defect healing at 4 and 8 weeks after surgery, and samples from the skull defect area and major organs of the rats were obtained for histological staining at 8 weeks after surgery. Results: The scaffolds had a pore size of (480 ± 25) μm, a fiber diameter of (300 ± 25) μm, and a porosity of approximately 66%. The PCL-Mg scaffolds contained 1.0 At% Mg, indicating successful incorporation of Mg microparticles. The contact angle of the PCL-Mg scaffolds was 68.97° ± 1.39°, indicating improved wettability compared to that of pure PCL scaffolds. Additionally, compared with that of pure PCL scaffolds, the compressive modulus of the PCL-Mg scaffolds was (57.37 ± 8.33) MPa, demonstrating enhanced strength. The PCL-Mg group exhibited the best bone formation behavior in the skull defect area compared with the control group and PCL group at 4 and 8 weeks after surgery. Moreover, quantitative parameters, such as bone volume (BV), bone volume/total volume (BV/TV), bone surface (BS), bone surface/total volume (BS/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N) and bone mineral density (BMD), of skull defects were better than those in the other groups, indicating the best bone regeneration effect. H&E, Goldner, and VG staining revealed more mineralized new bone formation in the PCL-Mg group than in the other groups, and H&E staining of the major organs revealed good biosafety of the material. Conclusion PCL-Mg scaffolds can promote the repair of bone defects and have clinical potential as a new scaffold material for the repair of maxillofacial bone defects.