OBJECTIVE To optimize the formulation for sustained-release particles of matrine(MAT) and paeonol(PAE) and to primarily evaluate their quality. METHODS The sustained-release particles were fabricated by the extrusion-spheronization method. Single factor analysis was conducted on the main sustained-release materials and their dosage, auxiliary sustained-release materials, and the total amount and proportion of mixed sustained-release materials, using the cumulative release rates of MAT and PAE in vitro as evaluation indicators. By combining central composition design-response surface methodology, the formulation of sustained-release materials was optimized, and the effects of the total amount and mass ratio of ethyl cellulose(EC) and chitosan(CS) on the cumulative release rate and release synchronization of MAT and PAE were investigated. The formulation characteristics, in vitro release, and preliminary stability tests of MAT-PAE-SRPs were evaluated, and the release process kinetic equation was fitted. RESULTS The optimized formulation contained 23.5% EC and 17.1% CS as sustained-release materials. The yield, repose angle, bulk density and friability of final particles were 97.23%, 38.1°, 0.74 g·mL−1 and 0.74%, respectively. The particles showed sustained release pattern in various media and released faster in acidic media with its release percentage >90% at 12 h. The release profile of MAT was fitted best with first order equation, and that of paeonol with Higuchi equation. The formation of SRPs improved the stability of both drugs. CONCLUSION The sustained-release effect of MAT-PAE-SRPs prepared by sustained-release materials EC and CS is significant, and the cumulative release rate and release synchronization of MAT and PAE are good, which can provide reference for the research of dual loaded sustained-release formulations.

Objective To investigate the relationship between gait spatiotemporal parameters and balance function in stroke hemiplegic patients. Methods From September, 2018 to March, 2020, 76 stroke hemiplegic patients (38 in Brunnstrom Ⅳ and V, respectively) were assessed balance function with Active Balancer EAB-100 and Star Excursion Balance Test (SEBT), and gait parameters of speed, cadence and asymmetry, named step length asymmetry ratio (SLA), swing time asymmetry ratio (SWTA), stance time asymmetry ratio (STA), maximum flexion angle ratio (MFA) of hip and knee. The correlation among gait parameters and balance function was analysed. Results The balance and gait parameters were better in those in Brunnstrom V than in Brunnstrom Ⅳ (|t| > 2.268, P < 0.05). The speed and cadence correlated with the most balance indexes (|r| > 0.335, P < 0.05). SLA correlated with SEBT in Brunnstrom Ⅳ patients (r = -0.467~-0.613, P < 0.01), while it correlated with medial-lateral (M-L) stability limits in Brunnstrom V patients (r = -0.356, P = 0.028). SWTA correlated with stability limit of Anterior-Posterior (A-P) (r = -0.335, P = 0.040) and M-L (r = 0.510, P = 0.001), and most of SEBT (r = -0.330~ -0.445, P < 0.05) in Brunnstrom Ⅳ patients. MFA of hip and knee correlated with balance indexes in Brunnstrom Ⅳ patients (|r| > 0.326, P < 0.05), while MFA of knee correlated with most balance indexes in Brunnstrom V patients (r > 0.329, P < 0.05), and MFA of hip correlated with A-P stability limit (r = 0.369, P = 0.023). Conclusion Both speed and cadence of steps can well respond to the balance function in stroke hemiplegic patients. For the asymmetry, it is related with balance in patients with poorer recovery.