1.Elementary study on construction of engineered blood vessel using chitosan-fibrin gel as scaffold
Yingxin XU ; Tai YIN ; Ruixin LI ; Shihe WU ; Jinjing WANG ; Lingling E ; Xizheng ZHANG ; Rong LI
Chinese Journal of Rehabilitation Theory and Practice 2005;11(8):623-625
ObjectiveTo investigate the feasibility of construction of engineered blood vessel using chitosan tube and fibrin gel as scaffold.MethodsVascular endothelial cells and smooth muscle cells were harvested from aortas of a rat, respectively. After expansion in vitro, vascular endothelial cells were seeded onto the inner surface of chitosan tube and smooth muscle cells mixed with fibrin gel seeded onto outer surface of the scaffold to construct engineered blood vessels. Inverted microscope, immunohistochemical staining and scanning electronic microscope were used to evaluate the construct.ResultsVascular endothelial cells formed monolayer and covered the inner surface of chitosan tube. Smooth muscle cells survived in the fibrin gel and grew in a 3-dimensional manner. ConclusionChitosan-fibrin gel may be potentially used as scaffold of engineered blood vessels.
2.Experimental Study of Vascular Tissue Engineering
Tai YIN ; Yingxin XU ; Shihe WU ; Jinjing WANG ; Lingling E ; Rong LI ; Ruixin LI ; Xizheng ZHANG
Chinese Journal of Rehabilitation Theory and Practice 2007;13(6):526-527
Objective To obtain the experimental data of vascular tissue engineering.MethodsThe vascular endothelial cells (VEC) and vascular smooth muscle cells (VSMCs) were acquired and cultured, and then seeded on vascular tissue engineering materials. The porous gelatin-chitosan scaffold with VSMCs was subcutaneously implanted, followed by the observation of the cell growth ten days later.ResultsThe two kinds of cells were successfully cultured and their morpholoical and immunohistochemical characteristics were consistent with vascular endothelial and VSMCs respectively. The VSMCs could grow extensively on the scaffold after the in vivo implantation. The scaffold were wrapped by the fibrous tissue ten days later after the in vitro implantation of VSMCs. The seed cells grew in the scaffold, and the vessel cavity seen in the center of the scaffold, was quite different from the normal vessel structure.ConclusionIt is feasible to implant the VSMCs with fibrin gels into the living body. The vessels reconstructed, though different from the normal structure, is similar to the embryo of the vessels.
3.Comparative evaluation of multilocus variable-number tandem-repeat analysis and pulsed-field gel electrophoresis for genotyping Salmonella enterica serovar Typhi isolates
Weiyuan WU ; Hui WANG ; Jian LU ; Yingxia LIU ; Yuemei LU ; Jinsong WU ; Wenqing LI ; Jin′e CHENG ; Wenyuan WU
Chinese Journal of Microbiology and Immunology 2014;(4):264-268
Objective To evaluate the capability of multilocus variable-number tandem-repeat ( VNTR) analysis ( MLVA) and pulsed-field gel electrophoresis ( PFGE) for genotyping Salmonella enterica serovar Typhi (S.Typhi) isolates.Methods Five polymorphic VNTRs (SAL02,SAL11,SAL16,SAL20, and TR4699 ) that were observed in S.Typhi strains from previous studies were selected to establish MLVA . Twenty-one epidemiologically unrelated S.Typhi strains that were isolated from Shenzhen ,China from 2002 to 2007 were genotyped by the established MLVA , and the results were compared with those by PFGE . Results The Simpson′s index of diversity ( D value ) for all five different VNTRs ranged from 0.838 to 0.943 .A total of 19 MLVA profiles and 19 PFGE profiles were found , respectively .The D value for both MLVA and PFGE were 0.99 and the test results from two analyses were identical .Conclusion The five polymorphic VNTRs analysis could be used as an alternative typing scheme for epidemiologic investigation of S.Typhi infection .
4.Molecular cha ratce irs it cs of the extended-spectrum β-lactamase and/or AmpC enzyme-producing Proteus mirabilis strains prevelant in Shenzhen People′s Hospital
Weiyuan WU ; Jian LU ; Yuemei LU ; Jinsong WU ; Wenqing LI ; Jin′e CHENG ; Xunhong LIANG ; Wenyuan WU ; Yingxia LIU
Chinese Journal of Microbiology and Immunology 2014;(6):423-430
Objective To investigate the prevalence and molecular characteristics of the extended -spectrum β-lactamase ( ESBL) and AmpC enzyme-producing Proteus mirabilis ( P.mirabilis) strains isola-ted in Shenzhen People′s Hospital.Methods The production of ESBLs and AmpC enzymes by P.mirabilis isolates were detected by a screening and confirmatory test for ESBLs and AmpC disk test , respectively .The PCR assays followed by DNA sequencing of the products were employed to analyze the multiple genes inclu -ding the ESBLs genes, AmpC genes, insertion sequences (ISs) upstream of the ESBLs or AmpC genes, plasmid -mediated quinolone resistance ( PMQR ) determinants , quinolone resistance-determining region (QRDR) genes , the integrase genes, and class1 integron cassette.The epidemiological analysis of the iso-lates was performed by pulsed field gel electrophoresis .Results There were 130 P.mirabilis clinical iso-lates collected from Shenzhen People′s Hospital in China during the year 2004 to 2010.Among them, 13 isolates (10%) produced ESBLs, that accounted for 0%-9.1%in the year 2004-2009 and up to 29.4%in 2010, and 3 isolates (2.3%) produced AmpC enzymes.The predominant genotype of ESBLs -producing isolateswas b al CTX-M-14(n=7), followed by blaCTX-M-65(n=3), blaCTX-M-55(n=1), blaCTX-M-24(n=1) and blaPER-1 (n =1).The clinical isolate of PER-1-producing P.mirabilis was reported for the first time in China.Twoisolates carried an AmpC β-lactamase gene of blaCMY-2 and one isolate carried an unidentified AmpC gene .ISEcp1 located upstream of blaCTX-M and blaCMY-2 were detected in 91.7% (11/12) of CTX-M-producing isolatesand one CMY-2-producing isolate, respectively.ISPa12 was present upstream of blaPER-1 in one studiedisolate.Approximately 66.7% (10/15) of ESBL and /or AmpC-producing isolates harbored PMQR genes including2 carrying qnrD, 5 carrying aac-Ib-cr and 3 carrying both qnrD and aac-Ib-cr.Twelve ESBL and /orAmpC-producers with high level of resistance to ciprofloxacin carried the similar mutation profiles of S 83I inGyrA, S80I or S80R in ParC and among them, six strains showed E466D mutation in GyrB.Approximately86.7% (13/15) of ESBL and/or AmpC-producing isolates carried class 1 integron.Fourteen PFGE typeswere observed among 15 ESBL and/or AmpC-producers.Conclusion The prevalence of CTX-M β-lactamasesin P.mirabilis isolates contributed to the increased resistance to extended -spectrum cephalosporins.The qnrD and/or aac-Ib-cr genes were detected among the most of ESBL and /or AmpC-producing P.mirabilis clinical isolates.
6.A validation study of starting use of new freezing bags in cord blood bank
Jinsong CHEN ; JieYing WU ; Yan LU ; Gui′e XIE ; ZunPeng XU ; Yan LI ;
International Journal of Laboratory Medicine 2014;(20):2820-2822
Objective To verify whether the storage bag can reach the use requirement of cord blood freezing storage by conduc-ting a series of tests before staring use of new type cryopreservation bag for cord blood.Methods According to the standard opera-tion procedure,28 new type cryopreservation bags were extracted.The cord blood units were performed the cryostorage and thaw for rewarming according to the standard operating procedures.Then the physical integrity and various quality indicators of cord blood in bag were detected,including the nucleated cell viability,cell recovery rate,CD34-positive cell,colony-forming cultivation of stem cells,sterility test and verification of actual load volume.Results All the tested storage bags passed the integrity test,and the various testing indicators of the preserved cells conformed to the use requirements.Conclusion The new type storage bag has the same performance and effect to original bag,it is verified that the maximum loading volume of 50 mL(for 50 mL specification of storage bag)and 80mL(for 250mL specification of storage bag)is safe.
8.Synergism of As2S2 and STI 571 in inducing apoptosis of K562 cells.
Jun-e LI ; Guan-lin SUN ; Ying-li WU ; Wei-li WU
Chinese Journal of Hematology 2003;24(11):580-583
OBJECTIVETo investigate the synergistic effect of As(2)S(2) and STI 571 on K562 cells and its mechanism.
METHODSThe inhibitive effect of As(2)S(2) on the proliferation of K562 cells was determined by cell number count. Cell apoptosis was assessed by flow cytometry, DNA fragmentation and morphology. Protein expression was determined by Western-blot and gene expression by RT-PCR.
RESULTSAs(2)S(2) could significantly inhibit the proliferation and induce apoptosis of K562 cells in a dose and time-dependent manner at concentrations from 1 micromol/L to 5 micromol/L for 24 approximately 72 h. 34.4%, 21.8% and 46.0% of the treated-cells displayed apoptosis at 3 micro mol/L for 72 h, 5 micromol/L for 48 h and 5 micromol/L for 72 h, respectively. Compared to treatment with STI571 (0.25 approximately 1.00 micromol/L) or As(2)S(2) (1 approximately 5 micromol/L) alone, treatment of K562 cells with As(2)S(2) and STI571 combination induced more cell apoptosis. (18.4 +/- 1.4)% and (15.8 +/- 1.2)% cells underwent apoptosis at 1 micromol/L STI571 for 48 h and 5 micromol/L As(2)S(2) for 48 h, respectively, and (40.6 +/- 2.0)% cells did in combination treatment (P < 0.05). For U937 cells, the percentages of apoptotic cells were (6.0 +/- 1.1)% at 1 micromol/L STI571 for 48 h, (4.5 +/- 1.2)% at 5 micromol/L As(2)S(2) for 48 h, and (7.3 +/- 1.0)% in combination treatment. As(2)S(2) decreased the bcr-abl fusion protein expression and PTK activity of c-abl and bcr-abl, but not for bcr-abl expression.
CONCLUSIONCombination treatment with As(2)S(2) and STI 571 induced more apoptosis of K562 cells. The reduction of PTK activity may be involved in the mechanisms.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Benzamides ; Cell Division ; drug effects ; Dose-Response Relationship, Drug ; Drug Synergism ; Fusion Proteins, bcr-abl ; analysis ; genetics ; Humans ; Imatinib Mesylate ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; pathology ; Piperazines ; pharmacology ; Pyrimidines ; pharmacology
9.Preliminary study on the molecular mechanism of K562 cell apoptosis induced by As2S2.
Jun-e LI ; Guan-lin SUN ; Ying-li WU ; Wei-li WU
Chinese Journal of Oncology 2003;25(3):220-224
OBJECTIVETo investigate the apoptotic inducing effect of As(2)S(2) on K562 cells.
METHODSThe apoptotic inducing effect of As(2)S(2) on K562 cells was determined by flow cytometry, DNA fragmentation analysis and morphology observation. Expression of protein was determined by Western-blot. RT-PCR was used to evaluate changes in gene expression.
RESULTSApoptosis of K562 cells was induced by 48 - 72 h exposure to 5 micromol/L As(2)S(2). Apoptosis was induced in (34.4 +/- 3.3)% treated cells by 72 h exposure to 3 micro mol/L As(2)S(2), in (21.8 +/- 3.6)% treated cells by 48 h exposure to 5 micromol/L As(2)S(2) and in (46.0 +/- 5.2)% treated cells by 72 h exposure to As(2)S(2) at the same concentration. With 5 micromol/L As(2)S(2), the protein level of Bcr-Abl and JAK2 decreased, while bax expression was upregulated and c-myc was downregulated both in protein and mRNA level. The activity of caspase 3 in K562 cells was increased by As(2)S(2). As(2)S(2) also induced apoptosis of fresh mononuclear cells derived from chronic myelogenous leukemia (CML) patients.
CONCLUSIONAs(2)S(2) can induce apoptosis of CML cells. The decline of Bcr-Abl may play an important role. The upregulation of bax, increase of the activity of caspase 3, downregulation of c-myc and decrease of JAK2 may also be involved in the mechanism.
Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Caspase 3 ; metabolism ; Fusion Proteins, bcr-abl ; analysis ; Humans ; Janus Kinase 2 ; analysis ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; pathology ; Sulfides ; pharmacology ; bcl-2-Associated X Protein ; analysis
10.Expression of glucose transporter-1 and insulin receptor alpha1 in osteoblast obtained from diabetic rats' mandibles.
Xuan WU ; Hongchen LIU ; Lingling E ; Zhenchun LI
West China Journal of Stomatology 2011;29(4):348-354
OBJECTIVETo explore the expression of glucose transporter (GLUT)-1 and insulin receptor (IR) alpha1 in osteoblast obtained from diabetic rats' mandibles.
METHODSThe expression of GLUT-1 and IR alpha1 of diabetic and control groups were measured by reverse transcription polymerase chain reaction, Western blot and immunohistochemistry stain.
RESULTSThe mRNA expressions of GLUT-1 and IR alpha1 of diabetic group were significantly higher than control group (P<0.05). The protein expressions of GLUT-1 and IR alpha1 were similar to the mRNA expressions.
CONCLUSIONOsteoblasts obtained from diabetic rats' mandibles keep the adaptation changes to hyperglycemia and hypoinsulinemia, which may contribute to their dysfunction.
Animals ; Diabetes Mellitus, Experimental ; Glucose Transport Proteins, Facilitative ; Mandible ; Osteoblasts ; Rats ; Receptor, Insulin