RESUMEN
BACKGROUND: Telesurgery has the potential to overcome spatial limitations for surgeons, which depends on surgical robot and the quality of network communication. However, the influence of network latency and bandwidth on telesurgery is not well understood. METHODS: A telesurgery system capable of dynamically adjusting image compression ratios in response to bandwidth changes was established between Beijing and Sanya (Hainan province), covering a distance of 3000 km. In total, 108 animal operations, including 12 surgical procedures, were performed. Total latency ranging from 170 ms to 320 ms and bandwidth from 15-20 Mbps to less than 1 Mbps were explored using designed surgical tasks and hemostasis models for renal vein and internal iliac artery rupture bleeding. Network latency, jitter, frame loss, and bit rate code were systemically measured during these operations. National Aeronautics and Space Administration Task Load Index (NASA-TLX) and a self-designed scale measured the workload and subjective perception of surgeons. RESULTS: All 108 animal telesurgeries, conducted from January 2023 to June 2023, were performed effectively over a total duration of 3866 min. The operations were completed with latency up to 320 ms and bandwidths as low as 1-5 Mbps. Hemostasis for vein and artery rupture bleeding models was effectively achieved under these low bandwidth conditions. The NASA-TLX results indicated that latency significantly impacted surgical performance more than bandwidth and image clarity reductions. CONCLUSIONS: This telesurgery system demonstrated safety and reliability. A total of 320 ms latency is acceptable for telesurgery operations. Reducing image clarity can effectively mitigate the potential latency increase caused by decreased bandwidth, offering a new method to reduce the impact of latency on telesurgery.
RESUMEN
This study aimed to determine whether aldosterone could induce vascular cell apoptosis in vivo.Thirty-two male rats were randomly divided into 4 groups: vehicle(control),aldosterone,aldosterone plus eplerenone or hydralazine.They were then implanted with an osmotic mini-pump that infused either aldosterone or the vehicle.Systolic blood pressure(SBP)was measured weekly by the tail-cuff method.After 8 weeks,plasma aldosterone concentration(PAC)and renin activity(PRA)were determined by radioimmunoassay.Aortic apoptosis was examined by TUNEL assay.The levels of cytochrome c and caspase-3 were determined by Western blotting and the expression of Bax and Bcl-2 was detected by immnuohistochemistry and Western blotting.The results showed that as compared with control group,aldosterone-infused rats exhibited:(1)an increase in SBP;(2)significantly elevated PAC with depressed PRA;(3)elevated aortic vascular cell apoptosis accompanied with higher levels ofcytochrome c and activated caspase-3; and(4)significantly up-regulated Bax protein with down-regulated Bcl-2.These effects of aldosterone were significantly inhibited after co-administration with eplerenone but not with hydralazine.It was concluded that aldosterone inducedvascular cell apoptosis by its direct effect on the aorta via mineralocorticoid receptors and independently of blood pressure,which may contribute to aldosterone-mediated vascular injury.
RESUMEN
The single needle method for urethrovesical anastomosis with strengthened posterior fixation during laparoscopic radical prostatectomy was explored. The method was initiated by performing a fixing suture with a knot at 4 o'clock of the posterior lip of bladder neck,and another suture at nearby position was performed to leave the knot outside. From 5 o'clock to 8 o'clock,sutures were performed every one o'clock to secure posterior approximation,then every two o'clock a suture.To avoid a loose anastomosis,lock sutures were performed every 3 sutures. The needle was always driven full-thickness outside-in in the bladder neck and inside-out on the urethra. After completing the full circumference,the needle was drawn near the 4 o'clock and tied at the tail end. Any leakage could be closed with additional interrupted sutures. The clinical data of 89 patients who underwent this method were retrospectively compared with those of 23 patients who underwent the single knot method. The results showed that the anastomosis,operative and catheterization time was 17.6±4.7min,134.0±10.7 min and 6.5±1.6 days respectively. There were 3 temporal urinary leakages identified in 89 cases requiring prolonged catheterization. No urinary leak and anastomotic stricture was confirmed,and 95.2% patients had total urinary control. It was concluded that this method was simple and safe for urethrovesical anastomosis.
RESUMEN
To investigate the relationship between the expression of RASSFIA protein and promoter hypermethylation of RASSFIA gene, RASSFIA protein expression was measured by Western blot- ting in 10 specimens of normal bladder tissues and 23 specimens of bladder transitional cell carci- noma (BTCC). The promoter methylation in BTCC and normal bladder tissues was detected by me- thylation-specific PCR (MSP). The results showed that the expression level of RASSFIA protein was significantly lower in BTCC tissues than that in normal bladder tissues. However, it was not corre- lated with its clinical stages and pathological grades. The frequency of promoter methylation of RASSF1A gene was higher in BTCC tissues than that in normal bladder tissues. In 14 patients with the aberrant promoter methylation, 13 showed loss or low expression of RASSF1A protein. It is con- cluded that RASSFIA gene promoter methylation may contribute to the low level or loss of RASSFIA protein expression, the inactivation of RASSFIA gene and the genesis of BTCC. But, it may bear no correlation with its clinical stages and pathological grades.