1.The effect of a biodegradable paclitaxel-eluting stent on bile duct healing after trauma in a porcine model
Chinese Journal of General Surgery 2013;28(11):842-845
Objective To evaluate the effect of a biodegradable paclitaxel-eluting biliary stent on bile duct scar formation and biliary stricture by observing the healing process after stent placement in a porcine billiary model.Methods A novel biodegradable paclitaxel-eluting biliary polylactide stent was manufactured by immersion method.The efficacy of drug release for paclitaxel-eluting biliary stent was investigated by HPLC.Paclitaxel-eluting stent were surgically inserted in the bile duct of fifteen swines in experimental group while stent without paclitaxel were placed in other fifteen swines in control group.Animals were sacrificed after 1,3,6 months.The anastomic healing of the common bile duct was observed.The size of anastomosis was measured and compared between the two groups.Result A novel biodegradable paclitaxel-eluting biliary stent was manufactured.The total amount of paclitaxel released was about 281 pg (30.4%) over a month as determined with HPLC methods.There was no death,no leakage.The diameter of anastomosis in the experimental group was significantly larger than that in control group.Cholangiography did not show obvious bile duct dilatation in experimental group.Histologic examination showed less hyperplasia of the bile duct wall in the experimental group than that in control group.Conclusion Release of paclitaxel via a biodegradable stent relieves billiary stricture in porcine model and have no obvious negative influence on wound healing of the common bile duct.
3.Endovascular repair combined with second-stage surgical debridement for ruptured femoral pseudoaneurysms due to drug injection
Yuanyuan GUO ; Bin YANG ; Hongbo CAI ; Hui JIN
Journal of Chinese Physician 2014;16(3):310-312
Objective To evaluate the feasibility,safety,and efficacy of endovascular repair combined with second-stage surgical debridement for ruptured femoral pseudoaneurysms (RFP).Methods All patients who underwent emergency repair of an RFP in our institution between 2009 and 2013 were identified.Case notes were retrieved for clinical data.Results Seven patients were identified.All the patients were treated with emergent percutaneous stent-graft implantation and secondary surgical debridement.The procedure time was (55 ± 6.32) min,blood loss was (93.33 ± 25.03) ml,hospital stay was (9.5 ± 0.84) d,and no postoperative complications occurred.Conclusions stent graft implantation for the treatment of RFPs is safe and effective in short-or middle-term outcome.It is an alternative for RFPs and may be the better option,which makes the secondary surgical debridement feasible and viable.
4.Core-crosslinked poly(N-isopropylacrylamide-co-N,N-dimethylacrylamide)-b-poly(ε-caprolactone)micelles for paclitaxel thermo-sensitive controlled release behaviors
Qing CAI ; Lei ZHANG ; Jing YANG ; Riguang JIN
Chinese Journal of Tissue Engineering Research 2010;14(29):5505-5510
BACKGROUND: Polymer micelles is a new type of drug carriers developed in recent years,with a wide range of carrying drugs,structural stability,excellent tissue permeability,long residence of drugs in vivo,and effective reaching the target.The performances of intelligent targeting and decreasing the initial burst release have become the focus of recent researches.OBJECTIVE: To obtain an intelligent targeting drug carrier of low critical solution temperature(LCST)at 40℃,to change drug release behavior through the changes of temperature,and to further improve the stability and drug release behavior of the micelles by core-crosslinking.METHODS: By radical polymerization of N-isopropylacrylamide(NIPAAm)and N,N-dimethylacrylamide(DMAAm),hydroxyl terminated poly(N-isopropylacrylamide-co-N,N-dimethyl acrylamide)[P(NIPAAm-co-DMAAm)]was synthesized.Molecular weight and LCST of P(NIPAAm-co-DMAAm)were regulated by adjusting the mercaptoethanol and monomer ratio,as well as the ratio of NIPAAm and DMAAm,Amphiphilic block copolymer P(NIPAAm-CO-DMAAm)-b-PCL was prepared via bulk ring-opening polymerization of ε-caprolactone by using the end hydroxyl group of P(NIPAAm-co-DMAAm)as initiator and stannous octoate as catalyst.The block copolymer reacted with acryloyl chloride to obtain amphiphilic block copolymers with unsaturated double bonds at the terminal.Drug loaded nano-micelles with different nuclear cross-linked degrees were prepared by dialysis method,and its release behavior was investigated.RESULTS AND CONCLUSION: Amphiphilic block copolymers,with the LCST of 42℃,were obtained with hydroxyl or acryloyl endgroup.By blending them at different ratios,thermo-sensitive drug-loaded nano-micelles with different core-cresslinking degrees were prepared.The drug release rate was faster at 43℃ than at 37℃.With the core-crosslinking degrees increasing,the release of paclitaxel gradually slowed.The results suggest that the drug release rate from micelles prepared from thermo-sensitive P(NIPAAm-co-DMAAm)-b-PCL can be regulated by the degree of cross-linking.
6.Study on Bilingual Teaching of Microbiology in Western College of China
Ming-Guo JIANG ; Li-Fang YANG ; Jin-Cai XUAN ;
Microbiology 1992;0(06):-
Bilingual teaching is one of education reform in China.The essay analyzed the necessity of bilingual teaching and clarified the reason why it can procced in microbiology.Search after the way in microbiology course according to the character of college in western China.The practice accumulated experience for bilingual teaching.
7.Isolation,Identification and Degradation Characteristics of a DMP-degrading Strain
De-Cai JIN ; Xue-Ling WU ; Ren-Xing LIANG ; Qin-Yun DAI ; Yang-Yang WANG ; Yu YANG ;
Microbiology 2008;0(09):-
A bacterial strain which could grow well on the substrate of PAEs as the sole source of carbon and energy was isolated from contaminated sludge in the river of WeiFang in ShangDong province and it was designated as JDC-3. Based on the morphology,biophysical and biochemical properties as well as molecular characteristics,this isolate was preliminarily identified as Delftia sp.. A fragment of phthalate dioxygenase gene was successfully amplified from the genus of Delftia for the first time using a set of degenerate primers. Meanwhile,the degradation capability of JDC-3 was determined by HPLC using DMP as test substrate. The results showed that the optimal pH and temperature were at 7.0~8.0 and 30?C~35?C respectively. The degradation kinetics of JDC-3 was studied in different initial DMP concentration under optimal conditions. The results indicated that the degradation dynamic equation was ln C =-0.06837 t + A when DMP concentration was lower than 300 mg/L,with half life of 12.48 h. The degradation rate decreased and half life of JDC-3 prolonged as the initial concentration kept on increasing.
8.The discrimination system of pancreatic endoscopic ultrasonography image based on M-band wavelet transfom
Minmin ZHANG ; Hua YANG ; Zhendong JIN ; Zheyuan CAI ; Jianguo YU ; Zhaoshen LI
Chinese Journal of Digestive Endoscopy 2010;27(8):419-422
Objective To develop and evaluate the digital discrimination system for pancreatic ultrasound endoscopy images. Methods EUS images of 153 pancreatic cancer and 63 non-cancer cases were selected. According to the multi-fractal feature vectors based on the M-band wavelet transform, we acquired the fractal features with lower dimension with the feature screening algorithm. With the optimal feature combination, cases were classified into pancreatic cancer group and non-pancreatic cancer group automatically.Then the sensitivity, specificity and accuracy of this method were calculated, and compared with those of traditional 9 dimension fractal feature vectors. Results Three kinds of multi-fractal dimensions were introduced to the framework of M-band wavelet transform according to the EUS images to form fractal vectors of 18 dimension. With the selection by sequence forward search (SFS) algorithm, 7 dimension of feature vectors were chosen and were combined with bi-order multi-fractal dimension to a better feature combination. The Bayes, support vector machine (SVM) and ModestAdaBoost classifiers were introduced to evaluate the classification efficiency, resulting in a classification accuracy of 97.98% and short running time of 0. 49 s with lower feature dimension. Conclusion These data suggest the feasibility, accuracy, noninvasiveness and efficacy of classification of EUS images to differentiate pancreatic cancer from normal tissue based on the Mband wavelet transform algorithm. It is a new and valuable research area in diagnosis of pancreatic cancer.
9.Explore the protective effects of the bone marrow mesenchymal stem cells on severe acute pancreatitis in rats
Yuqiang SHAN ; Liang LUO ; Zhong JIA ; Yang CAI ; Huicheng JIN ; Guanghua FENG
Chinese Journal of Emergency Medicine 2013;22(4):395-399
Objective To investigate effects of bone marrow mesenchymal stem cells (MSC) on severe acute pancreatitis (SAP) in rats.Methods A total of 60 rats were randomly divided into normal group (n =10),the model of SAP group (n =10),the transplantation of the MSC group (n =20),the combination of the MSC and the granulocyte colony-stimulating factor (G-CSF) group (n =20).The conversion rate of MSC was detected by using immunofluorescence methods,and the level of amylase in serum was assayed by using biochemical methods.Simultaneously,the level of interleukin-6 (IL-6) in serum was determined by using enzyme linked immunosorbent assay (ELISA).Results The conversion rates of the MSC increased,and consequently,the levels of amylases and interleukin-6 in serum were reduced (P < 0.05).When a small amount of the G-CSF was added to MSC,the therapeutic effects of the two different kinds of cells were synergistically strengthened.In the contrary,when a large number of the G-CSF was added to MSC,the antagonism resulted between these two different kinds of cells gives rise to harmful effects on SAP.Conclusions The bone marrow mesenchymal stem cells have therapeutic effects on SAP.When the number of the bone marrow mesenchymal stem cells increases,the protective effects are enhanced.
10.Analysis of multiple drug resistance of 2311 strains of Helicobacter pylori isolated from patients of different ages
Zizhong JI ; Xia JIN ; Feng HAN ; Chenxiao CAI ; Li WAN ; Minfang CHEN ; Ningmin YANG
Chinese Journal of Digestion 2013;33(12):826-830
Objective To investigate condition of single drug or multiple drug resistance and sensitivities of different combinations of antibiotics in Helicobacter pylori (H.pylori) infected patients of different ages in Jiaxing City,Zhejiang Province.Methods From January 2007 to December 2011,a total of 6280 patients underwent gastroendoscopy examination were enrolled,the average age of them was 50.8 years old.Among them,129 cases were less than 20 years old,1802 cases were between 20 and 40,3016 cases were between 40 and 60,and 1333 cases were over 60.The mucosa of gastric antrum was collected for H.pylori culture.Drug sensitivity of isolated H.pylori strains was tested with metronidazole,amoxicillin and gentamycin,furazolidone,clarithromycin and levofloxacin.x2 test was performed for the comparison of drug resistance among different age groups.Results Among 6280 specimens,H.pylori culture of 2311 cases was positive (positive rate 36.80%).The positive rate of patients aged between 40 and 60 was the highest (38.43%,1159/3016),and that of patients over 60 was the lowest (33.76%,450/1333).The drug resistance rate of metronidazole in patients between 20 and 40 years reached 98.02% (644/657) and was the highest.The drug resistance rate of clarithromycin in patents over 60 years old was the highest,which was 22.67%(102/450).The drug resistance rates of the levofloxacin,furazolidone,amoxicillin and gentamicin were low of all ages.Mixed resistance of two antibiotic appeared in 586 strains,mixed resistance rate of metronidazole and clarithromycin was the highest (259 strains,15.23 %).Mixed resistance of three drugs appeared in 49 strains,mixed resistance rate of metronidazole,clarithromycin and levofloxacin was the highest (32 strains,12.88%).A total of 1691 strains were sensitive to the combination of amoxicillin and gentamycin,the sensitive was rate 99.41%.The sensitive rate of the combination of amoxicillin and furazolidone,gentamycin and furazolidone was both 94.24%.Conclusions Metronidazole presented high drug resistance of all ages,and should not be chosen.The combination use of amoxicillin and gentamicin is the ideal antibiotic combination for different ages.The combination of gentamycin and furazolidone is recommended for patients who are allergic to penicillin.