RESUMO
Attributed to the miniaturized body size and active mobility, micro- and nanomotors (MNMs) have demonstrated tremendous potential for medical applications. However, from bench to bedside, massive efforts are needed to address critical issues, such as cost-effective fabrication, on-demand integration of multiple functions, biocompatibility, biodegradability, controlled propulsion and in vivo navigation. Herein, we summarize the advances of biomedical MNMs reported in the past two decades, with particular emphasis on the design, fabrication, propulsion, navigation, and the abilities of biological barriers penetration, biosensing, diagnosis, minimally invasive surgery and targeted cargo delivery. Future perspectives and challenges are discussed as well. This review can lay the foundation for the future direction of medical MNMs, pushing one step forward on the road to achieving practical theranostics using MNMs.
RESUMO
OBJECTIVE： To study the repair effect of artificial Isaria cicadae on intestinal mucosal injury induced by 5-fluorouracil （5-FU） in rats. METHODS： Forty SD rats were randomly divided into normal group （normal saline）， model group （normal saline）， artificial I. cicadae high-dose， medium-dose and low-dose groups （3.5， 1.75， 0.875 g/kg）， with 8 rats in each group. Except for normal group， other groups were given intraperitoneal injection of 5-FU （0.25 g/10 mL） 30 mg/kg， once a day， for consecutive 5 days. At the same time， each group was given relevant medicine/normal saline intragastrically， once a day， for consecutive 8 d. After medication， body weight of rat was determined in each group. HE staining was used to observe the pathological change of small intestine. The levels of biobarrier-related factor [endotoxin （ET）， D-lactic acid （D-LA）]， immune barrier related factors （TNF-α， IFN-γ， sIgA， IL-15， G-CSF in serum and MPO， MDA in small intestine） and the levels of mechanical barrier related factors （connexin ZO-1 and Claudin-1） were detected. RESULTS： Compared with normal group， body weight of rats in model group was decreased significantly （P＜0.01）. Intestinal villus exfoliated obviously， the crypt structure was scattered， a large number of inflammatory cells gathered， and intestinal mucosa was seriously damaged. Serum levels of ET and D-LA， the levels of TNF-a， IFN-γ， MPO and G-CSF in serum， MDA level in small intestine were increased significantly （P＜0.01）. Serum levels of sIgA and IL-15 as well as the expressions of ZO-1 and Claudin-1 in small intestine were decreased significantly （P＜0.05 or P＜0.01）. Compared with model group， body weight of rats in artificial I. cicadae high-dose group was increased significantly （P＜0.01）. The pathological changes of the small intestine of rats in each administration group were improved to varying degrees. The intestine morphology of artificial I. cicadae high-dose and medium-dose groups was close to that of the normal group. The levels of and ET， D-LA， TNF-α， IFN-γ， MPO， G-CSF in serum and the level of MDA in intestinal were decreased significantly （P＜0.01）. Serum levels of sIgA and IL-15 in administration groups as well as the expressions of ZO-1 and Claudin-1 in intestinal tissue were increased significantly （P＜0.01）. CONCLUSIONS： Artificial I. cicadae can repair intestinal mucosal damage caused by 5-FU in respects of mechanical barrier， immune barrier， biological barrier.