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Objective To explore the role and underlying mechanism of heat shock protein 27 (HSP27) in bladder smooth muscle remodeling after bladder outlet obstruction (BOO). Methods Rat BOO model was established by urethral orifice hyaluronic acid injection, and the rats from the control group were given the injection of same amount of normal saline. In 4 weeks after model establishment, the bladder wall tissues of BOO and control group were observed by HE staining. The expression of HSP27 and RhoA was detected by Western blotting in both groups. Cultured human bladder smooth muscle cells (BSMCs) were transfected with lentiviral vectors expressing either HSP27 or HSP27-shRNA (shHSP27). Western blotting was used to detect the expression of HSP27, phosphorylated HSP27, RhoA, G-actin and F-actin. Phalloidin fluorescence staining of F-actin was performed in overexpression and control group to observe actin filaments in BSMCs. Results HE staining showed evident bladder smooth muscle hypertrophy in BOO group in 4 weeks after hyaluronic acid injection, indicating the successful establishment of rat BOO model. The expression levels of HSP27 and RhoA were increased significantly compared to those in the control group (P < 0.05). BMSC cell models of HSP27 overexpression and knockdown were successfully established. The Results of Western blotting showed increased expression of HSP27, phosphorylated HSP27 and RhoA in HSP27 overexpression cells (P < 0.05), and decreased expression of these protein in shHSP27 cells (P < 0.05). Also, the F-actin/G-actin ratio was elevated in HSP27 overexpression cells (P < 0.05) and an opposite result was seen in the shHSP27 cells (P < 0.05). Phalloidin fluorescence staining showed there were less actin filaments in shHSP27 cells than the control and HSP27 overexpression cells, and more actin filaments in abnormal arrangement were observed in the overexpression cells than the control cells. Conclusion HSP27 can affect the structure of actin by regulating RhoA, and may play a critical role in bladder smooth muscle remodeling after BOO in rats.

Objective To evaluate the safety and effectiveness of retroperitoneal laparoscopic nephroureterectomy combined with transurethral resection of the ureteral orifice for the treatment of upper urinary urothelial carcinoma (UTUC). Methods We retrospectively analyzed the clinical data of 59 UTUC cases treated in our hospital from July 2013 to July 2019, who underwent retroperitoneal laparoscopic nephroureterectomy combined with transurethral resection of the ureteral orifice (n=20) or abdominal incision(n=39). Blood loss volume, time of incision drainage, recovery time of postoperative intestinal function, postoperative hospitalization time, postoperative complications and local recurrence, and distant metastasis were compared between the 2 groups. Results The transurethral resection group had significantly longer operative time (219.1±54.2 vs 178.7±60.8 min, P < 0.05), but shorter time of incision drainage, recovery time of postoperative intestinal function and postoperative hospitalization time (P < 0.05) when compared with the abdominal incision group. There were 4 cases having operative complications in the abdominal incision group, including 2 cases of pulmonary infection, 1 case of retroperitoneal effusion, and 1 case of lymphorrhagia. In the transurethral resection group, there was 1 case of postoperative bladder bleeding, and cystoscopic electrocision was performed for hemostasis. No significant differences were found in other evaluated indicators between the 2 groups. Conclusion Retroperitoneal laparoscopic nephroureterectomy combined with resection of the ureteral orifice is safe and effective for the treatment of UTUC. Compared with abdominal incision, transurethral approach has the advantage of less trauma and rapider recovery.

Objective To compare the efficacy and safety of photoselective sharp-enucleation of prostate with end-firing fibre (PSEP) and tranuretheral resection of the prostate (TURP) in the treatment of large-size benign prostatic hyperplasia (BPH). Methods According to the inclusion and exclusion criteria of the study, totally 94 BPH patients with prostate volume (PV) >80 mL admitted in our hospital from July 2018 to December 2019 were prospectively enrolled, and then randomized into TURP and PSEP group, with 47 cases in each group. Preoperative and perioperative data were collected, and maximum flow rate (Qmax), international prostate symptom score (IPSS), post-void residual urine (PVR), quality of life score (Qols), score of international consultation on incontinence questionnaire-urinary incontinence-short form (ICI-Q-SF), prostate-specific antigen (PSA) level, PV and related complications in 1 and 6 months after surgery were recorded and compared between the 2 groups. Results There were 43 and 44 patients completing the followed-up in PSEP and TURP groups respectively in 6 month postoperatively. No significant differences were found in baseline data between the 2 groups, and Qmax, PVR, PSA level, and scores of IPSS, Qols and ICI-Q-SF were significantly improved at 1 and 6 months after surgery in both groups. The operation time (71.6±21.2 vs 87.6±18.9 min, P < 0.01), bladder irrigation time (7.1±5.7 vs 19.8 ±8.6 h, P < 0.01), catheterization period (3.4±1.7 vs 4.4±1.6 d, P < 0.01), and length of hospital stay (4.3±1.0 vs 5.2±1.3 d, P < 0.01) were significantly shorter in the PSEP group than those in the TURP group. The former group also had remarkably milder haemoglobin dropping (5.5±3.2 vs 12.2±6.6 g/L, P < 0.01), and more obviously smaller PV (21.3±4.0 vs 25.2±6.1 mL, P < 0.01) in 6 months when compared with the latter group. What's more, there was no statistical difference in the incidence of postoperative complications between them. Conclusion Both PSEP and TURP show good efficacy and safety in the treatment of large-size BPH. Compared with TURP, PSEP has the advantages of high surgical efficiency, less bleeding, more thorough tissue removal, and faster postoperative recovery. It is an optional choice for the patients with large-size BPH.

Reconfigurable machine tools realize the processing conversion of each part in the part family through the exchange of its functional modules. However,due to the influence of machine structure layout and module weight,how to ensure the performance and accuracy of the machine tool under the condition that the modules are interchangeable is a difficult problem in the research field of reconfigurable machine tools. A mechanical interface device which can micro-adjust the module pose and ensure the stiffness of the machine tool is proposed in this paper. The comb-tooth joint surface and auxiliary supports used in the interface can realize the precise positioning and improve the connection stability between the machine-tool modules. The pose of the machine-tool module is adjusted slightly through the elastic-expansion-ball interface-unit deformation caused by the preload force exerted by the lock bolt on it. The preload deformation and connection stiffness of the interface unit are coordinated by different arrangement of the steel balls in it. The finite element analysis model of the mechanical interface is established,and the influence of different structure sizes and loading conditions on the stiffness characteristics of the mechanical interface is analyzed accordingly,which lays a theoretical foundation for the further application of the mechanical interface.

Objective To compare the efficacy and safety of a novel procedure, green light top-firing, sharp enucleation of the prostate (GTSEP) and the traditional procedure, photoselective vaporisation of the prostate (PVP) in the treatment of benign prostatic hyperplasia (BPH). Methods A total of 154 patients diagnosed with BPH admitted in our hospital from June 2018 to April 2019 were recruited in this study, and then randomly divided into GTSEP group (n=77) and PVP group (n=77). All patients were assessed preoperatively and followed at 1 and 6 month postoperatively. International prostate symptom score (IPSS), quality of life score (QoLs), post-void residual urine (PVR), maximum urine flow rate (Qmax), prostate volume (PV), prostate-specific antigen (PSA) and complications were recorded and compared between the 2 groups. Results There were 74 patients in each group completing the follow-up. No significant differences were found in baseline data between the 2 groups. At 1 and 6 months after surgery, both groups had their lower urinary tract symptoms significantly improved, but there were no significant differences in IPSS, QoLs, PVR, Qmax and PSA between the 2 groups. However, the GTSEP group had significantly shorter operation time (41.0±16.4 vs 50.1±18.1 min, P=0.001), and smaller prostate volume at 6 months after surgery (22.4±2.4 vs 23.3±1.9 mL, P=0.011) when compared with the PVP group. No notable differences were seen in the incidence of intraoperative and postoperative complications between the 2 groups. Conclusion Both GTSEP and PVP achieve good efficacy and safety in BPH treatment. GTSEP can remove larger hyperplastic tissue than PVP, and is superior to PVP in operation efficacy.

This paper introduces the structure and working principle of SR type steering gear, describes an example of stuck failure of the steering gear. The author uses the exclusion method and the shallow to deep method to analyze the causes of the failure from five aspects, and finally locates the failure, and then proposes two aspects of steering gear management considerations.

The causality of passive linear materials dictates both sound absorption performance and structure thickness, making it challenging in the design of thin structures that can approach the causality limits. In contrast to the traditional structure with single damping, a hybrid-damping coupling method is introduced here based on a high-order metamaterial, allowing for superior absorption performance in a thinner structure. In the hybrid-damping high-order cell, the first-order peak is applied with an over-damping impedance to shift the peak toward a lower frequency with the structure thickness unchanged, while the high-order peaks are optimized with matched-damping impedance, avoiding their rapid attenuations in absorption ability. By introducing opposite phases for two first-order peaks, 100% absorption can also be achieved at lower frequencies upon strict coupling. Owing to the near-perfect absorption, the high-order peaks allows for a more sparse arrangement and a lower peak density when coupled, which results in fewer restrictions on peak frequency and greater design flexibility. Therefore, a wider absorption band with superior performance can be achieved in the high-order metamaterial with a fixed number of peaks. By critically coupling 15 high-order cells, a broadband Helmholtz metamaterial is obtained with 95% mean absorption within 210–1860 Hz under a thickness of 135 mm, which is verified by experiments in a square impedance tube. This metamaterial can provide a new way for the low-frequency broadband absorption design and show great potential in noise control engineering applications. [ABSTRACT FROM AUTHOR]