1.Modification and application of the third-generation adenovirus vectors
Academic Journal of Second Military Medical University 2000;0(07):-
Adenovirus as gene transfer vector is characterized by high transfection efficiency,high titer,good stability in target cells and low pathogenicity,and has been widely used in gene therapy.Compared to first-and second-generation adenovirus vectors,the third-generation adenovirus vectors have unique advantages for gene therapy because of their low immunogenicity and high capacity.However,the clinical application of the third-generation adenovirus vectors is hampered by the existance of helper contamination and difficulties in their large-scale production.
2.Histological observation of mandibular advancement in goat using tooth-borne distraction osteogenesis device
Xue FENG ; Fulin CHEN ; Zhu LIN
Journal of Practical Stomatology 1996;0(02):-
Objective:To observe the histological character of distraction osteogenesis(DO) in the mandible of goat using an intraoral tooth-supported distraction device. Methods:8 goats (7-9 months of age) were divided into 4 groups with 2 goats per group. After a bilateral mandibular corticectomy between the second and third premolars, self-produced intraoral tooth-supported distraction devices were cemented. 5 days after operation,the distraction devices were begun to be activated 0.25 mm every 12 hours to advance the anterior segment 8 mm in 16 days. The animals of 32 days group were injected with tetracycline fluorescence labeing at 10 ml/kg once perweek from the beginning of DO.The animals were sacrificed on day 8,16,32 and 48 separately post activation, and tetracycline fluorescence labeling,HE staining and Mallory's 3-color staining were performed. Results:Tetracycline fluorescence labeling showed that there was green-yellow fluorescence labeling new bone within the distraction gap; HE and Mallory's trichrome staining showed that new bone gradually formed from bilateral sides, gradually blending and remodeling. The fiber bundles and newly formed trabeculas and various cells in early phrases showed to be orientation-directed along the axis of distraction force. Conclusion: New bone can be formed and regenerated along the axis of distraction force within the distraction gap.
3.A case of neurofibroma of vocal fold.
Kai CHEN ; Huang LIN ; Xue-fen LI
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2011;46(5):428-429
Adult
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Humans
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Laryngeal Neoplasms
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Male
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Neurofibroma
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Vocal Cords
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pathology
4.Purification of Trypsin by Using AOT/Isooctane Reverse Micellar Extraction and Overcoming Denaturation and Precipitation in the Process
China Biotechnology 2006;0(01):-
Trypsin was purified from crude material of pig pancreas by AOT/isooctane reversed micellar system.The influence of the main operating parameters such as ethanol concentration in forward and backward extraction,pH,KCl and AOT concentration,temperature were investigated.Forward and backward extraction recovery of trypsin reached almost 90% and neared 100%,respectively.Finally,about 88% of total yield was obtained,and the specific activity of trypsin was increased to over 1800U/mg with purification factor of 5 folds more.In AOT-isooctane reverse micellar extraction system,denaturation or precipitation of proteins always occured due to strong electrostatic interaction between AOT-proteins molecules.It had been resolved by adding ethanol into reverse micellar system,and no denaturation was observed.Otherwise,the phase separation time was shortened significantly because of ethanol added.It was only 10 minutes or less to reach phases separation after forward and backward extraction.If this method can be applied in industry,efficiency will be greatly improved.
5.Injectable and biodegradable thermosensitive PLGA-PEG-PLGA copolymer-based hyd rogels for a controlled in vitro drug delivery
Zhikui CHEN ; Liwu LIN ; Yahfang LIN ; Ensheng XUE ; Liyun YU
Chinese Journal of Tissue Engineering Research 2008;12(49):9792-9796
BACKGROUND:Ricin possesses strong cytotoxicity but lacks of specificity.Severe adverse reactions can be caused if ricin is systemically administered.Interstitial chemotherapy with ricin coated by a sustained-release carrier can enhance local therapeutic effects of tumor,avoiding systemic-toxic occurrence.OBJECTIVE:To prepare injectable and biodegradable thermosensitive poly(D,L-lactide-co-glycolide)(PLGA)-polyethylene glycol(PEG)-PLGA copolymer-based hydrogels and to observe the in vitro drug delivery of the PLGA-PEO-PLGA copolymer hydrogel as a sustained-release carrier of ricin.DESIGN,TIME AND SETTING:A controlled observation was performed at the Center for Medical Bioengineering.Fujian Medical University between August and December 2007.MATERlALS:Ricin with a purity of 95%was purified by Fuiian Institute of Ultrasonic Medicine.DL-lactide and L-glycolide were provided by Glycolide Lactide Co.,Ltd..China.METHODS:PLGA-PEG-PLGA-copolymer was synthesized by ring-opening polymerization.MAIN OUTCOME MEASURES:Phase transition temperature was determined by test tube turnover.relativemolecular mass by high-performance gel permeation chromatography,the proportion of block copolymer by nuclear magnetic resonance spectrometry.the in vitro drug delivery of ricin coated by PLGA-PEG-PLGA copolymcr hydrogelby enzyme linked immunosorbent assay.the structural integrity of released ricin by high-performance liquid chromatography,the cytotoxicity of released ricin by methyl thiazolyl tetrazolium assay.RESULTS:The synthesized copolymer PLGA-PEG-PLGA exhibited reverse.thermosensitivity.The phase transition temperature of the copolymer was 26℃at 230 g/L.The weight-average molecular weight and number-average molecular weight of this copolymer was 8 027 and 6 643,respectively,and the multiple-dispersion toefficient was 1.17.The block ratio for PEG and PLGA was 3:2.Drug-loaded PLGA-PEG-PLGA hydrogel could release ricin in vitro for a total of 18 successive days and simultaneously well maintain cytotoxicity and the structural stability of ricin.CONCLUSION:PLGA-PEG-PLGA copolymer is an ideal carrier for sustained delivery of ricin
6.Predicting changes of fertility index after varicocelectomy on color Doppler ultrasonography
Ensheng XUE ; Rongxi LIANG ; Liwu LIN ; Xiaodong LIN ; Shun CHEN
Chinese Journal of Ultrasonography 2010;19(1):36-39
Objective To discuss color Doppler uhrasonographic (CDU) grading of varicocele (VC) in predicting the changes of the fertility index (FI) after varicocelectomy.Methods One hundred and fifty-one patients with VC were diagnosed and graded by CDU.All patients were grouped by the regurgitant volume and the maximum diameter of pampiniform plexus veins(PPV).The relation between the regurgitant volume and the maximum diameter of PPV and the changes of the FI after varicocelectomy was analyzed.Results The pathological regurgitation could be detected when the PPV diameter > 1.5 mm.The positive correlation was observed between the regurgitant volume and the diameter of PPV (r = 0.89, P <0.01).The pre- and postoperative FIs were extremely significant difference in regurgitation grade Ⅱ and regurgitation grade Ⅲ (P < 0.01) but not significant difference in regurgitation grade Ⅰ (P>0.05).The pre- and postoperative FIs were no significant difference in the group with the PPV diameter ≤ 2.0 mm (P > 0.05), but statistically significant difference in the groups with the diameters 2.1-2.5 mm and 2.6-3.0 mm (0.01 < P <0.05).FIs in the group with the diameter > 3.0 mm exhibited extremely significant difference after varicocelectomy (P < 0.01).Conclusions CDU grading of VC could be used to predict the changes of seminal quality after varicocelectomy.Varicocelectomy isn't necessary to the patients with VC that the PPV diameter ≤ 2.0 mm or pathological regurgitation being detected only on Valsalva maneuver.
7.Application of ultrasonography in diagnosing and preoperative TNM staging for neuroendocrine breast cancer
Xiaoshuang CHEN ; Liwu LIN ; Ensheng XUE ; Zhikui CHEN ; Yimi HE
Chinese Journal of Ultrasonography 2015;24(10):894-897
Objective To investigate the value of ultrasonography in diagnosis and preoperative TNM staging for neuroendocrine breast cancer(NEBC).Methods The ultrasonic characteristics of 12 NEBC and 104 invasive ductal carcinoma(IDC) confirmed by pathology,as well as the metastatic lymph nodes were analyzed retrospectively.The TNM-staging for NEBC by preoperative ultrasonography was evaluated according to pathology.And the relation between lesions size and Ki-67 was then analyzad.Results NEBC lesions mainly showed solid and heterogeneous hypoechoic(66.67%),irregular shape(66.67%),clear border (58.33 %),posterior enhancement(58.33 %) and internal blood flow(grade 0-Ⅰ) (66.67 %).The detection rate of unclear border,irregular edge,hyperechoic halos and uneven internal echo was lower than IDC(P < 0.05).Meanwhile,NEBC had a lower detection rate of calcification and internal blood flow(grade Ⅱ-Ⅲ)than IDC (P >0.05).And the detection rate of more round or oval lesions were higher in NEBC than that in IDC (P =0.001).According to pathology,the ultrasonic coincidence rate for T staging of NEBC and pathology was 75%,and for T1-staging was 100%,for T2-staging was 80%.The sensitivity,specificity,positive predictive value and negative predictive value of ultrasonic diagnosis on lymph node metastases was 66.67%,88.89%,66.67% and 88.89%,respectively.There was a positive correlation between focal maximum diameter with Ki-67 (r=0.026,P=0.004).Conclusions It shows certain value of ultrasonography in diagnosis and preoperative TNM staging for NEBC.
9.Ultrasound-guided chemical ablation using compound lauromacrogol in treatment of tumor xenograft
Zhenpeng QU ; Zhikui CHEN ; Yimi HE ; Ensheng XUE ; Liwu LIN
Chinese Journal of Ultrasonography 2014;23(1):62-65
Objective To investigate the tumor chemical ablation and analgesic effects of compound lauromacrogol,and to explore a new method for ultrasound-guided tumor ablation.Methods 18 VX2 tumorbearing rabbits were randomly divided into saline group,ethanol group and compound lauromacrogol group,and the medicine was intratumoral injected guided by ultrasonography.After 4 times treatment,tumor contrast-enhanced ultrasonography,tumor growth inhibition rate and tumor tissue pathology were performed to evaluate the antitumor effects.The analgesic effect was evaluated using the pain model induced by formaldehyde test.Results Ultrasound-guided intratumoral injection of compound lauromacrogol showed significant antitumor effects with a tumor growth inhibition rate of 63.3 %,which was higher than that of ethanol group.No apparent enhancement was found under contrast-enhanced ultrasonography,and pathology results confirmed wide necrosis.In saline,ethanol and compound lauromacrogol groups,the average accumulated points were 62.25 ± 9.79,21.00 ± 9.13 and 9.87 ± 3.10,respectively by formaldehyde test.Conclusions Ultrasound-guided chemical ablation using compound lauromacrogol showed complete antitumor and strong analgesic effects,which would be a new method for tumor ablation.