Objective To explore the analgesic effect of intra-articular botulinum neurotoxin type A (BoNTA) injection in rats with adjuvant-arthritis pain,to quantify the expression of calcitonin gene-related peptide (CGRP) in the dorsal root ganglia (DRG) associated with arthritis pain,and to investigate the retrograde axonal transport of BoNT-A into the DRG after peripheral injection.Methods Ninety Sprague-Dawley rats were randomly divided into groups A,B,C,D and E,each of 18.A murine model of adjuvant-arthritis pain was established by injecting 50 μL of complete Freund's adjuvant into the left ankle in all the mice except those in group A.The control group A was treated with intra-articular injection of 50 μL of saline solution.Three weeks later,groups A and B were treated with a 20 μL intra-articular saline injection,while groups C,D and E received an intra-articular injection of BoNT-A at 1 U/20 μL,3 U/20 μL or 10 U/20 μL respectively.Pain threshold and muscle strength were graded before and 1,5,15 and 21 days after the modelling,as well as at 1,3,5 and 14 days after the BoNT-A treatments.Protein expression and the CGRP-positive cell number were observed,as well as any BoNT-A-cleaved synaptosomal-associated 25 kDa protein (cl-SNAP-25) in the DRG using Western blotting and immunofluorescence.Results Compared with group A,there was a significant decrease in the average mechanical withdrawal threshold and muscle strength and a significant increase in the protein expression and the CGRP-positive cell number in the other 4 groups.Compared with group B,the mechanical withdrawal threshold had increased significantly more in groups D and E at 5 days after the BoNT-A injection and in group C at 14 days after the treatment.Compared with group B,the protein expression and the number of CGRP-positive cells were significantly lower in groups D and E at 3 days after the BoNT-A injection.The decrease in group C was significant after 14 days.No significant differences were found between groups D and E in any measurement at any time point.There was no significant difference among groups B,C and D in terms of muscle strength.Five days after the BoNT-A injection,significantly decreased muscle strength was observed in group E.In addition,BoNT-A cleaved-SNAP-25 was detected in the DRG.Conclusion BoNT-A can reduce arthritis pain through inhibiting the expression of CGRP in the DRG.Its analgesic effect has a dose response.A peripheral injection of BoNT-A can arrive at the DRG through retrograde axonal transport.

Objective:To investigate the predictive value of peritoneal protein clearance (Pcl) for cardiovascular events and cardiovascular mortality in peritoneal dialysis (PD) patients.Methods:Eligible PD patients were prospectively enrolled from January 2014 to April 2015 in the PD Center of Renji Hospital, School of Medicine, Shanghai Jiao Tong University. All patients were followed up until death, withdrawing from PD, transferring to other centers, or the end of study period (October 1, 2018). The patients were divided into high Pcl group and low Pcl group by the median Pcl, and the differences of related indicators between the two groups were compared. A multiple linear regression model was used to analyze the influencing factors of Pcl. The Kaplan-Meier method and Log-rank test were used to compare the cumulative survival rates of patients between the two groups. A multivariate Cox regression model was used to estimate the risk of cardiovascular events and cardiovascular mortality in relation to Pcl in PD patients.Results:A total of 271 patients were enrolled, with 135 males (49.8%), age of (56.92±0.84) years old and a median PD duration of 38.77(19.00, 63.10) months. There were 70 patients (25.8%) comorbiding with diabetes and 81 patients (29.9%) with cardiovascular diseases (CVD). The median Pcl of this cohort was 67.93(52.31, 88.36) ml/d. Compared with the low Pcl group (Pcl<67.93 ml/d), the high Pcl group (Pcl≥67.93 ml/d) had older age, and greater proportion of CVD, body mass index (BMI), pulse pressure, brain natriuretic peptide, mass transfer area coefficient of creatinine (MTACcr), and lower serum albumin (all P<0.05). There was no significant difference in gender, dialysis duration, proportion of diabetes, proportion of angiotensin converting enzyme inhibitor and angiotensin receptor blocker, proportion of continuous ambulatory PD, high sensitivity C reactive protein, fluid removal including 24 h urine volume and 24 h ultrafiltration, and residual renal function between the two groups (all P>0.05). Multiple linear regression analysis showed that serum albumin ( β=-0.388, P<0.001), BMI ( β=0.189, P<0.001), and MTACcr ( β=0.247, P<0.001) were independently related to lg(Pcl). During the study period, 55 patients experienced one or more cardiovascular events and 39 patients had cardiovascular mortality. According to Kaplan-Meier analysis, cardiovascular mortality in the high Pcl group was higher than that of low Pcl group (Log-rank χ2=6.902, P=0.009). Multivariate Cox regression analysis showed that, high lg(Pcl) was an independent influencing factor of cardiovascular events in PD patients ( HR=7.654, 95% CI 1.676-34.945, P=0.009). Conclusions:Serum albumin, BMI and MTACcr are independently associated with Pcl, and Pcl is an independent predictor of cardiovascular events in PD patients.