Ischemic stroke (IS) ranks as a leading cause of death and disability globally. The blood-brain barrier (BBB) poses significant challenges for effective drug delivery to brain tissues. Recent decades have seen the development of targeted nanomedicine and biomimetic technologies, sparking substantial interest in biomimetic drug delivery systems for treating IS. These systems are devised by utilizing or replicating natural cells and their derivatives, offering promising new pathways for detection and transport across the BBB. Their multifunctionality and high biocompatibility make them effective treatment options for IS. In addition, the incorporation of engineering techniques has provided these biomimetic drug delivery systems with active targeting capabilities, enhancing the accumulation of therapeutic agents in ischemic tissues and specific cell types. This improvement boosts drug transport and therapeutic efficacy. However, it is crucial to thoroughly understand the advantages and limitations of various engineering strategies employed in constructing biomimetic delivery systems. Selecting appropriate construction methods based on the characteristics of the disease is vital to achieving optimal treatment outcomes. This review summarizes recent advancements in three types of engineered biomimetic drug delivery systems, developed from natural cells and their derivatives, for treating IS. It also discusses their effectiveness in application and potential challenges in future clinical translation.
Humans ; Drug Delivery Systems/methods* ; Ischemic Stroke/drug therapy* ; Animals ; Blood-Brain Barrier/metabolism* ; Stroke/drug therapy*

ObjectiveTo establish the characteristic sugar spectrum of polysaccharides， oligosaccharides and monosaccharides of wild-simulated and transplanted Astragali Radix， and find out the difference of the sugar spectrum between the two， so as to provide a basis for quality evaluation of Astragali Radix. MethodThe relative molecular weight distribution of polysaccharides from 18 batches of wild-simulated Astragali Radix and 12 batches of transplanted Astragali Radix were characterized by high performance liquid chromatography-evaporative light scattering detection（HPLC-ELSD） to establish the characteristic chromatograms of two kinds of polysaccharides. The difference in the peak area ratio of APS-Ⅱ， a polysaccharide component with a relative molecular weight of 10 kDa， in two kinds of Astragali Radix was analyzed， and the critical value of peak area ratio of APS-Ⅱ was determined by receiver operating characteristic（ROC） curve. At the same time， APS-Ⅱ was partially acid-hydrolyzed by trifluoroacetic acid（TFA） to establish characteristic spectra of two kinds of oligosaccharides from Astragali Radix based on HPLC-ELSD， and the characteristics of differential oligosaccharides were found by principal component analysis（PCA） and orthogonal partial least squares-discriminant analysis（OPLS-DA）. Two kinds of APS-Ⅱ were completely acid-hydrolyzed by TFA and derivatized to establish characteristic spectra of two kinds of monosaccharides from Astragali Radix based on HPLC， PCA and OPLS-DA were performed on the peak area ratio of two kinds of monosaccharides to explore the differences in the composition of two kinds of APS-Ⅱ monosaccharides. ResultThe characteristic sugar spectrum of polysaccharides from Astragali Radix showed that the peak area ratio of APS-Ⅱ was the main difference， and the peak area of APS-Ⅱ of wild-simulated and transplanted Astragali Radix were 89.17%-97.17% and 80.14%-91.96%， respectively. The ROC curve determined the critical value of 92.28% for the difference of APS-Ⅱ peak area ratio of the two kinds of Astragali Radix. The multivariate analysis of APS-Ⅱ oligosaccharides revealed that the peak area ratio of oligosaccharides with polymerization degree≥10 was the main difference， which ranged from 11.835%-19.092% for wild-simulated products and 2.778%-7.017% for transplanted products. The results of monosaccharide characteristic sugar spectrum analysis showed that both Astragali Radix species consisted of six monosaccharides， and glucose and arabinose were the differential monosaccharide fractions. The peak area ratios of glucose and arabinose in wild-simulated products were 85%-93.9% and 2.7%-5.8%， respectively， while those of transplanted products were 74.3%-87.3% and 5.3%-10.7%， suggesting that the structures of the two polysaccharide fractions APS-Ⅱ of Astragali Radix may be different. ConclusionThe difference of sugar spectrum between two kinds of Astragali Radix may be related to the content and structure of APS-Ⅱ， and this study may provide a reference for the study of carbohydrates in Astragali Radix and the quality evaluation of medicinal materials.

Objective Analysis of roadblocks found in the reform of performance-based salary mechanism in public hospitals, along with recommendations for the implementation strategies. Methods Both the historical document method and qualitative method are called into play to identify the characteristics and measures for performance-based salary mechanism in public hospitals. Results Such roadblocks are mostly found in value measurement of the hospital services of welfare nature, criteria of appraisal and establishment of the indicator system, job evaluation and the extent of incentives to use. The authors hold that such reforms should go in parallel with the reform, development, management level upgrading, and cultural building of the hospitals, and should call into play roles of intermediacies. Conclusion Reform for performance-based salary mechanism will be inevitable in public hospitals, as it has a direct bearing on the mission and functionality of public hospitals. In spite of the difficulties met, appropriate strategies may powerfully push forward reforms and development of such hospitals.