Methods, Mechanisms, and Application Prospects for Enhancing Extracellular Vesicle Uptake.

Extracellular vesicles (EVs) are considered to be a new generation of bioinspired nanoscale drug delivery systems due to their low immunogenicity, natural functionality, and excellent biocompatibility. However, limitations such as low uptake efficiency, insufficient production, and inhomogeneous performance undermine their potential. To address these issues, numerous researchers have put forward various methods and applications for enhancing EV uptake in recent decades. In this review, we introduce various methods for the cellular uptake of EVs and summarize recent advances on the methods and mechanisms for enhancing EV uptake. In addition, we provide further understanding regarding enhancing EV uptake and put forward prospects and challenges for the development of EV-based therapy in the future.

[Case-control study on the treatmentof the fifth metatarsal base fractures by cardboard compression pad versus short leg plaster].

OBJECTIVE: To compare the effect,safety,and advantage of flexible fixation with paperboard and pad versus short leg plaster in treating the fifth metatarsal base fracture,and establish the standard of diagnosis and treatment of the fifth metatarsal base fractures in flexible fixation with paperboard and pad. METHODS: From June 2010 to March 2013,59 patients with the fifth metatarsal base fracture were treated with paperboard and pad fixation or short leg plaster. Patients were enrolled and divided into paperboard and pad treatment group (paperboard group) and short leg plaster treatment group (plaster group) randomly according to the random number table. In paperboard group,there were 29 cases including 9 males and 20 females with an average age of (51.79±11.40) years old; the average course of injury was (11.59±6.58) hours. In plaster group, there were 30 cases including 9 males and 21 females with an average age of (52.13+17.34) years old ;the average course of injury was (11.03±7.06) hours. According to whether the fracture line across the articular surface, in paperboard group there were 14 cases of type A,15 of type B; in plaster group,16 of type A, 14 of type B. According to the degree of dislocation,in paperboard group there were 16 cases of degree I ,13 of degree II ; in plaster group,20 were degree I ,10 were degree II. Fracture was restored according to the type in manual. Patients in paperboard group were treated with paperboard and pad, and patients in plaster group were treated with short leg plaster. Fracture was fixed for 4 to 6 weeks according to fracture healing. On the 2nd, 4th,6th, 8th week and 3rd, 6th month after fixation, patients were followed up, and the foot function score was used to evaluate the function of injured foot. X-ray of injured foot was taken on the 2nd, 4th, 6th and 8th week were used to assess fracture healing. RESULTS: All patients got complete follow-up. The X-ray result showed that all fracture reached at clinical healing on the 8th week after fixation without skin ulcer,nonunion and displacement of fracture. From the 4th to 8th week after fixation, paperboard group had a higher X-ray score than plaster group, but the difference between two groups had no statistically significance. Repeated analysis result showed that there was interact at different time point and between groups,the difference had statistically significance (P<0.01). The foot function score showed that at all time point, paperboard group had a higher score than plaster group, and on the 2nd, 4th, and 6th week, it had statistically significant difference(P<0.01) between two groups. On the 6th months after fixation,the excellent and good rate of paperboard group was 93.10%, higher than that of plaster group, which was 86.67%. But it had no statistically difference(P=0.483) between two groups. CONCLUSION: Using paperboard and pad fixation to treat the fifth metatarsal base fracture has the advantage of simplicity operating,reliable fixation, satisfactory effects, easily obtainable material.

[Clinical observation of jianpi bushen formula to prevent collapse of osteonecrosis of femoral head].

To observe the clinical effect of Jianpi Bushen formula to prevent the collapse of osteonecrosis of femoral head (ONFH) of type phlegm and blood stasis obstructing the collaterals. 50 cases (including 73 hips) of non-collapse ONFH (ARCO I, II, III a) were selected from the out-patient department of orthopedic in Guang'anmen Hospital attached to China Academy of Chinese Medical Science. All the cases fit for diagnostic criteria were given Jianpi Bushen formula and followed up. Staging criteria was ARCO classification. Harris score evaluated the hip function. The mean follow-up time was 4.2 years (3-5.4 years). After a mean of 4.2 years (3-5.4 years) followed-up, 12 hips collapse occurred while 61 hips not (the non-collapse rate was 83.56%). Collapse did not occurred among the all 7 hips at stage ARCO I (the non-collapse rate was 100%). Among the 49 hips at stage ARCO II, 9 hips collapse occurred while 40 hips not (the non-collapse rate was 81.63%). Among the 17 hips at stage ARCO III a, 3 hips collapse occurred while 14 hips not (the non-collapse rate was 82.35%). Kaplan-Meier analysis showed the average survival time of non-collapse was 5 years (4. 8-5.2 years). The 3 year survival rate of non-collapse was 92.5%. The 4 year survival rate was 74% and the condition tended to be stability trend. The Harris score was 71.93 +/- 11.25 before treatment and 81.63 +/- 12.16 after treatment, significantly different. These results suggest that: Jianpi Bushen formula is an effective method for treating ONFH of type phlegm and blood stasis obstructing the collaterals. It can delay or prevent the collapse of femoral head and significantly improve the hip function.

[Meta-analysis on efficacy and safety of external use of tradition Chinese medicines and western medicines in treating knee osteoarthritis].

OBJECTIVE: To assess the efficacy and safety of the external use of tradition Chinese medicine (TCM) in treating knee osteoarthritis. METHOD: By computer retrieval of MEDLINE, CNKI and VIP database on data from the establishment of database to May 2011,all of the randomized controlled trials on the external use of TCMs in treating knee osteoarthritis with western medicines as the control drugs were collected to screen out literatures in line with the inclusion standards. The quality of the included literatures was strictly assessed, and a meta-analysis was conducted by RevMan 5.1 software. RESULT: Totally 25 RCTs involving 2 159 patients were included [1152 patients in the TCM group (TCMG), 1007 patients in the western medicine group (WMG)], in which 21 articles were brought into the analysis on efficacy. The results of meta-analyses showed that the efficient rates of the TCMG and the WMG were 92.35% (941/ 1019) and 81.19% (712/877), respectively, OR = 2.88 [2.16-3.83], with a hypothesis testing on total effect of Z = 7.20 (P < 0.00001)], suggesting that the external use of TCMs had a better efficacy than the WMG. A total of 25 literatures were brought into the analysis on adverse effect. The adverse effects rate of the TCMG and the WMG were 1.30% (15/1 152) and 5.36% (54/1007), respectively, OR = 0.40 [0.11-1.38], Z = 1.46 (P = 0.15)], indicating no significant difference between them. The sub group analysis shows that compared with the external use of western medicines,the adverse effect rate of the two groups are similar [(1.87% (11/589): 1.60% (9/564)], OR = l.12 [0.48-2.58], Z = 0.26 (P = 0.80). But as for inhibitors NSAIDS and COX-2 for oral,the adverse effect rate of the TCMG was lower than that of the WMG [(1.07% (4/375): 15.46% (45/291)], OR = 0.11 [0.01-0.87], Z = 2.09 (P = 0.04). CONCLUSION: The efficacy of the external use of TCMs in treating OA is better than that of western medicines. The adverse effect rates of the external use of TCMs is equivalent to that of western medicines, and significantly lower than that of oral western medicines. But because of the poor quality of the included literatures, the final conclusion for the efficacy of TCMs in treating knee osteoarthritis could not be reached only based on this Meta-analysis and remain to be proved with the results of high-quality clinical studies.

[Effects on VEGF and VEGF mRNA expression of the tissues of periosteum in three-period treatment of TCM for the fractures in rabbit].

OBJECTIVE: To observe the effects of the three-period treatment theory of bone fracture in TCM (Traditional Chinese Medicine) on VEGF and VEGF mRNA expression in the issues of outer periosteum, endosteum and bone marrow of rabbits, and to explore the rationality of phasing method in TCM in treating fracture. METHODS: 3 mm bone defection were made at lower one third part of both radius in 140 male healthy rabbits. The rabbits were randomly divided into four groups, including three-period treatment group (TTG), one-period treatment group(OTG), positive medicine treatment group(PTG) and model control group (MCG). The rabbits in TG were treated with three-period treatment, rabbits in OTG were treated with one-period treatment, rabbits in PTG were fed by Guzhe-Cuoshangsan (a Chinese patent medicine which was used to treat bone fracture), rabbits in model control group were given no prescription or drug but distilled water as same dose as that of other groups. At day 3, 6, 9, 14, 28, 42 and 56, five rabbits from every group were randomly selected and were killed by aeroembolism. The left radiuses were taken out as the research object. Immunohistochemistry stain and in situ hybridization stain were performed to examinate the VEGF and VEGF mRNA expression in the outer periosteum, endosteum and bone marrow. RESULTS: The VEGF and VEGF mRNA expression of all TCM treatment groups were enhanced in the outer periosteum, endosteum and bone marrow at different time points in fracture healing. The VEGF and VEGF mRNA expression in the three tissues of TTG had the tendency of higher than that of the other groups at the most time points after operation. CONCLUSION: Treating fracture in stages has more predominant effect on the expression of VEGF and VEGF mRNA in the outer periosteum, endosteum and bone marrow than that of treating fracture with single prescription or drug.

[Effects on VEGF and VEGF mRNA expression in issues of callus in treating fracture of rabbit with three-period treatment theory of bone fracture in traditional Chinese medicine].

OBJECTIVE: To observe the effects of the three-period treatment theory of bone fracture in traditional Chinese medicine (TCM) on VEGF and VEGF mRNA expression in the issues of callus of rabbits. And to explore the rationality of phasing method in TCM in treating fracture. METHOD: one hundred and forty male and healthy rabbits were made 3 mm wide bone defection at lower one third part of both radius as fracture healing model. Then those rabbits were divided into four groups randomly, which are three-period treatment group (TTG), one-period treatment group (OTG), positive medicine treatment group (PTG) and model control group (MCG). Those rabbits in TTG were treated with three-period treatment. Those in OTG were treated with one-period treatment. Those in PTG were feed by guzhecuoshangsan, a Chinese patent medicine which is used to treat bone fracture. Those in model control group were given no prescription or drug but distilled water as same dose as that of other groups. At day 3, 6, 9, 14, 28, 42 and 56, five rabbits were selected from every group randomly and were killed by aeroembolism respectively. Their radius were taken out and the left one was taken as the research object. Immunohistochemistry stain and in situ hybridization stain were performed to examinate the VEGF and VEGF mRNA expression in the haematoma, fibrous callus and soft callus. RESULT: All TCM treatment groups can enhance the VEGF and VEGF mRNA expression in the haematoma, fibrous callus and soft callus at different time points in fracture healing. The VEGF and VEGF mRNA expression in the three issues of TTG had the tendency of higher than that of the other groups at the most time points after operation. CONCLUSION: TCM can promote the VEGF and VEGF mRNA expression in the haematoma, fibrous callus and soft callus. Different Chinese medicines play various roles on VEGF and VEGF mRNA expression at different stage of fracture healing. Treating fracture in three-period treatment has more predominant effect on the expression of VEGF and VEGF mRNA in the haematoma, fibrous callus and soft callus than that of treating fracture with single prescription or drug. It is necessary to treat fracture in stages.