1.Preparation and characterization of PLGA microspheres containing a staphylokinase variant (K35R)
Jintian HE ; Xianmei TAO ; Wei MO ; Houyan SONG
Acta Pharmaceutica Sinica 2006;41(1):12-18
Aim To produce poly (lactic-co-glycolic acid) (PLGA) microspheres, containing a staphylokinase variant (K35R, DGR) with reduced immunogenecity and antiplatclet aggregation activities,which allowed the preservation of protein stability during both particle processing and drug release.Methods DGR-loaded microspheres were fabricated using a double emulsion-solvent evaporation technique. The effects of preparative parameters, such as stirring rate, polymer concentration, and the excipients of both internal and external aqueous phase (W2 ), on DGR encapsulation efficiency and microsphere characteristics were investigated. In vitro and in vivo release of DGR were conducted and the cause for instability of DGR during release was also investigated. Results Moderate ultrasonic treatment of aqueous DGR/dichloromethane mixtures caused approximately. Eighty four per cent DGR denaturation.However, the activity recovery of DGR almost amounted to 100% when 2% polyvinyl alcohol (PVA) was added into the aqueous phase. It was found that NaCl in the external water phase significantly increased DGR encapsulation efficiency. Furthermore, NaCl in the external water phase played a role in determining size and surface morphology of microsphere. In vitro release test showed a burst release of DGR from microspheres, followed by sustained release of 50% total activity over 15 days. In vivo experiments showed that DGR released from microspheres sustained 5 days. Denaturation of DGR within microspheres might be resulted from acidic microclimate. Conclusion The stability of DGR was effectively protected during microencapsulation and a relatively high encapsulation efficiency of DGR was obtained. PLGA microspheres could be an effective carrier for DGR.
2.Preparation and characterization of poly (lactic-co-glycolic acid) microspheres containing RGD-hirudin
Qin YU ; Jintian HE ; Wei MO ; Yanling ZHANG ; Longsheng WANG ; Yingjun WU ; Houyan SONG
Fudan University Journal of Medical Sciences 2006;33(1):17-23
Purpose The main purposes of our research were to: 1. set up the method of the RGDHirudin microsphere preparation; 2. set up the method to test the activity and the content of the medicine contained in the microsphere; 3. analyse the key factors on the quality of the microsphere preparation. Methods Co-poly lactic acid glycolic acid (PLGA) microsphere was prepared by a modified solvent evaporation method by a double emulsion with the use of polyvinylalcohol (PVA) as emulsification; PLGA was used as biodegradable material and dichloromethane as organic solvent. The influence of formulation factors including the W1/O on microsphere diameter distribution and yield coefficient;PVA concentration on microsphere appearance, encapsulation and yield coefficient; ultrasound on spherulization average and medicine activity; stirring speed on spherulization average and microsphere appearance; PLGA on microsphere appearance and microsphere dispersity; concentration of NaCl on encapsulation efficiency, yield coefficient and medicine content etc were studied. Results The size of all the fabricated microsphere was measured according to the several factors that affect the particle size. The average diameter was 81.38 μm, which is good for further research. The medicine content and the percent yield of all the microsphere was high, which ranged from 83. 92% - 96. 3% and 79.93% - 95.05% respectively. The encapsulation efficiency was about 23.95% - 65. 13%. We found that the concentration of the NaCl and PVA were the very important factors to the encapsulation efficiency. Physiological activity of RGD-Hirudin containing in the microsphere and the release rate of the microsphere were controlled. Furthermore, the release rate was stable. Conclusions The physiologic activity of RGD-Hirudin released from the microspheres was stable. PLGA-RGD-Hirudin microspheres were controlled released by the in vitro studies. Therefore, the in vivo experiment was well grounded.
3.Emergency treatment of large amputated ear defect with auricular cartilage replantation.
Tun LIU ; Ge SONG ; Qingguo ZHANG ; Xu ZHOU ; Xuefeng HAN ; Yue WANG ; Jin QIAN ; Jintian HU
Chinese Journal of Plastic Surgery 2014;30(4):245-248
OBJECTIVETo investigate the emergency treatment for large amputated ear defect.
METHODSFrom Feb. 2010 to Oct. 2013, 5 cases with large unilateral amputated ear defects were treated. The amputated auricular cartilage was replanted subcutaneously in mastoid area at the first stage. Cranioauricular sulcus was reconstructed and skin grafting was performed at the second stage.
RESULTSAll cases were followed up for 3-6 months with satisfactory result. The reconstructed helix, scapha and cavity of auricular concha had similar color and elasticity as the ear at healthy side. Scar at donor sites, such as inguinal region and armpit, was inconspicuous.
CONCLUSIONSThe method of auricular cartilage replantation is an effective way for emergency treatment of large amputated auricular defect with less morbidity at donor site.
Adolescent ; Adult ; Ear Cartilage ; transplantation ; Ear, External ; injuries ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Replantation ; Treatment Outcome ; Young Adult
4.Long-term effect of neoadjuvant imatinib for locally advanced gastrointestinal stromal tumor
Zhenmeng LIN ; Mingfang YAN ; Yi WANG ; Shenghong WEI ; Jintian SONG ; Qilin GONG ; Luchuang CHEN ; Huizhe ZHENG
Chinese Journal of General Surgery 2019;34(4):315-318
Objective To explore the safety and long-term results of preoperative imatinib mesylate administration (IM) in patients with locally advanced gastrointestinal stromal tumors (GIST).Methods From Sep 2009 to Nov 2016,locally advanced GIST patients treated in Fujian Medical University Cancer Hospital were analysed retrospectively.Result 34 patients were included.Preoperative median IM treatment was 27 weeks(range 12-71 weeks).65% patients had a partial response to IM,35% showed stable disease.All patients underwent surgical R0 resection.The complication rate was 9% and no death occurred within 30 days post operation.The median follow-up time was 62.2 months (range of 13-89 months).20 patients continued to take imatinib orally,14 patients did not.The 3 year survival rate of patients undergoing surgery was 67%.Univariate analysis showed that tumor location,preoperative imatinib effect,pathology,targeted therapy after surgery were factors affecting prognosis.Multivariate analysis show that the independent risk factors affecting prognosis were tumor location,pathology,targeted therapy after surgery.Conclusion In locally advanced GISTs,preoperative IM is useful and safe that can effectively decrease tumor size,facilitating resection.