Biomedical subjects

Ming Jin

Publications and source records attributed to Ming Jin.

47 records · Page 3Linked to original sources

PubMed2003

[Expression of a secreted fusion protein consisting of anti-HER2 antibody and reversed caspase-3 and its suppression on growth of SKOV3 cells].

AIM: To investigate the killing effect on SKOV3 cells by fusion protein HER2-specific antibody-reversed caspase-3 in the secreted form. METHODS: The reversed human caspase-3 gene was subcloned into pCMV-e23scFv-PEII-PEIII to construct recombinant eukaryotic expression vector pCMV-e23scFv-PEII-revcasp-3 and transfect Jurkat cells. The secreted expression of the in culture supernatant of transfected Jurkat cells was detected by ELISA. The suppression of the fusion protein on growth of SKOV3 cells was examined by co-culture with supernatant of transfected Jurkat cells. RESULTS: There was the secreted expression of the fusion protein in Jurkat cells. Expressed product had the activity of inducing SKOV3 cells to death. CONCLUSION: The fusion protein expressed in the secreted form can targeted towards SKOV3 cells and kill them.

Antibodies↗

PubMed2003

[Construction of single-chain Fv Gene of Anti-HBsAg and its expression in COS-7 cells].

AIM: To subclone the V(L) gene and V(H) genes of anti-HBsAg and construct the single-chain Fv gene and to analyse the expression of the constructed gene in COS-7 cells. METHODS: A set of oligonucleotide primers were designed and used to amplify the V(H) and V(L) genes from Fab antibodies screened from phage antibody library. The products were cloned into pUC19 vector and their sequences were analysed. The V(H) and V(L) gene fragments were linked up by a peptide linker and a leader sequence added at 5' terminus of each gene (L-V(H)-Linker-V(L)) and designated as L-ScFv. The L-ScFv genes were inserted into the eukaryotic fusion protein expression vector pEGFP-N3 and transfected into COS-7 cells to express respectively. RESULTS: The coding sequences of V(H),V(L), linker and leader in all constructs were all correct. The expression of ScFv fusion protein was detectable by fluorescence microscope after transient expression in COS-7. The secretive expression of L-ScFv was confirmed by SDS-PAGE and Western blot analysis. And the binding specificity of the ScFvs with HBsAg were proved by indirect ELISA. CONCLUSIONS: Anti-HBsAg ScFv genes have been successfully constructed and expressed in COS-7 cells.

Animals↗

PubMed2003

[Inducible expression of reconstructed human caspase-6 gene in Hela cells].

AIM: To observe the pro-apoptotic effect of RCasp-6 gene in Hela cells. METHODS: RCasp-6 gene was amplified by PCR and cloned into the pIND vector. Hela cells were transfected with pIND-RCasp-6 and then inducced with ecdyson analogue. Expression of target gene was detected by immunocytochemical staining. Changes of the morphology and growth of Hela cells subjected to transfection of target gene were observed by HE staining and viable cell counting. RESULTS: RCasp-6 gene was cloned by PCR and its eukaryotic expression vector was successfully reconstructed. Expression of RCasp-6 gene in the transfected Hela cells leads to the morphological changes of the cells. Many of the transfected Hela cells shrunk and some cells were died. CONCLUSION: The expression of reconstructed human caspase-6 gene can efficiently accelerate death of Hela cells.

Apoptosis↗

PubMed2003

[Prokaryotic expression and bioactivity identification of Fab against human gamma-seminoprotein].

AIM: To construct the expression vector containing cDNA encoding Fab against human gamma-seminoprotein and express it in E. coli. METHODS: The genes encoding K chain and Fd against gamma-seminoprotein were acquired from pUC19-K and pBluescript KS( M13-)-Fd by restrictive enzyme digestion and then cloned into the expression vector pComb3 to construct recombinant expression vector pComb3-Fab. pComb3-Fab was transfected into and expressed in XLI-Blue. RESULTS: Fab against r-semino-protein was expressed in. XLI-Blue. Western blot analysis and immunocytochemical staining demonstrated that ex-pressed Fab could specifically bind to gamma-seminoprotein. CONCLUSION: Fab against gamma -seminoprotein has been expressed successfully with biological activity, which create favourable condition for further study on targeted therapy of prostate cancer.

Animals↗

PubMed2002

[Expression of tissue inhibitors of metalloproteinase in monkey trabecular meshwork cells and ciliary muscle cells].

OBJECTIVE: To identify tissue inhibitors of metalloproteinase (TIMP) released by normal monkey trabecular meshwork cells and ciliary muscle cells in vitro and to detect the roles of matrix metalloproteinase (MMP) and TIMP playing in trabecular outflow and uveoscleral outflow in normal eyes. METHODS: The expressions of TIMP and MMP in monkey trabecular meshwork and ciliary muscle cultures were detected by the technology of reverse zymography. RESULTS: (1) TIMP-1, TIMP-2 and TIMP-3 were found in both trabecular meshwork and ciliary muscle cultured cells. (2) The ratio of MMP/TIMP in trabecular meshwork cells was much higher than that in ciliary muscle cells. CONCLUSIONS: The different ratio of MMP/TIMP in these two types of cells suggests that the capability of degrading extracellular matrix in trabecular meshwork cells be much higher than that in ciliary muscle cells, that may be one of the reasons why conventional trabecular outflow is stronger than uveoscleral outflow.

Animals↗

PubMed2002

[Experimental study of anti-vascular endothelial growth factor hairpin ribozyme gene inhibiting growth of xenografted tumor of ovarian cancer cells].

OBJECTIVE: We propose to block the autocrine and (or) paracrine pathway of vascular endothelial growth factor (VEGF) in ovarian cancer by using anti-VEGF hairpin ribozyme gene to see whether the growth of tumor cells could be inhibited and to further exploit its mechanisms. METHODS: Anti-VEGF hairpin ribozyme gene eukaryotic expression vector was introduced into ovarian cancer cells SKOV(3) by using lipofectin mediation and positive clones were screened by genticin (G418); ribozyme (RZ) expression was confirmed by RNA dot blot; the VEGF expression of SKOV(3) cells before or after transfection were detected by reverse transcription polymerase chain reaction (RT-PCR) method, transmission electron microscopy demonstrated the morphologic changes of ribozyme-generating SKOV(3) cells; the growth of transfected cells in nude mice were detected. RESULTS: VEGF expression was decreased distinctly in SKOV(3) cells transfected by RZ (SKOV(3)-RZ) cells. Apoptosis cells were observed; the formation rate and growth speed of xenografted tumor slowed down. CONCLUSIONS: Anti-VEGF hairpin ribozyme gene can inhibit the expression of VEGF mRNA and VEGF in SKOV(3) cells. The growth of xenografted tumor in nude mice was inhibited by reduced angiogenesis. This provides an experimental basis for curing human ovarian cancer with antiangiogenesis method.

Animals↗

PubMed2002

[Experimental study of anti-VEGF hairpin ribozyme gene inhibiting expression of VEGF and proliferation of ovarian cancer cells].

BACKGROUND & OBJECTIVE: Growth of solid tumor metastases are critically dependent on angiogenesis. Vascular endothelial growth factor (VEGF), also known as vascular permeability factor, has been identified as one of the most potent inducers of tumor associated angiogenesis, studies have shown that VEGF plays an important role in angiogenesis which is associated with epithelial ovarian cancer. Until now, many strategies for gene therapy have been developed. Among them is Ribozyme-based therapeutics for cancer which might be devised to inhibit tumor growth or prevent metastases. Angiogenesis is required for sustained tumor growth, making the VEGF pathway another promising target for either small molecule or nucleic acid-based therapeutics. Little is known about the role of VEGF in ovarian tumorigenecity. We propose to block the autocrine and/or paracrine pathway of VEGF in ovarian cancer using anti-VEGF hairpin ribozyme gene to see whether the growth of tumor cells could be inhibited and to further exploit its mechanisms. METHODS: Anti-VEGF hairpin ribozyme gene eukaryotic expression vector was introduced into ovarian cancer SKOV3 cells by lipofectin mediation and positive clones were screened by G418; Ribozyme expression was confirmed by RNA dot blot; The VEGF expression of SKOV3 cells before or after transfection were detected by immunohistochemical and immunofluorescence and flow cytometer immunofluorescence methods, MTT, colony forming, soft agar colony forming, and FCM were used to observe the effect of proliferation to ovarian cancer cells. RESULTS: VEGF expression decreased distinctly in SKOV3-RZ cells. The growth of transfected SKOV3-RZ cells were slower, The average colony forming efficiency and soft agar colony forming efficiency of SKOV3-RZ cells(12.7 +/- 1.4 and 9.4 +/- 2.0, respectively) decreased distinctly (P < 0.001). The SKOV3-RZ cells of G1 stage increased(P < 0.01), the SKOV3-RZ cells of S stage were reduced(P < 0.01). CONCLUSIONS: Anti-VEGF hairpin ribozyme gene can inhibit the proliferation of ovarian cancer SKOV3 cells. This provides a experimental basis for cure human ovarian cancer with antiangiogenesis method.

Cell Division↗

PubMed2002

[Antagonistic effect of hydroxysafflor yellow A on the platelet activating factor receptor].

AIM: To observe the antagonistic effect of hydroxysafflor yellow A (HSYA) on the platelet activating factor (PAF). METHODS: Washed rabbit platelet (WRP) aggregation and rabbit polymorphonuclear leukocytes (PMNs) aggregation induced by PAF were observed by turbidimetric assay in vitro. The PAF receptor antagonistic effect of HSYA was investigated by radio ligand binding assay (RLBA). RESULTS: In RLBA the specific binding inhibition effect of HSYA was found to be concentration-dependent in three different [3H]PAF concentrations. In the experiments, WRP aggregation and rabbit PMNs aggregation induced by PAF (9.55 x 10(-10), 9.55 x 10(-6) mol.L-1) were both inhibited by HSYA in a concentration-dependent manner in vitro. The IC50 of HSYA to inhibit WRP and rabbit PMNs aggregation was 0.99 and 0.70 mmol.L-1, respectively. CONCLUSION: The PAF receptor binding can be antagonized by HSYA.

Animals↗

PubMed2002

[Experimental study on inhibitory effect of rutin against platelet activation induced by platelet activating factor in rabbits].

OBJECTIVE: To explore the inhibitory effect and mechanism of rutin against platelet activating factor (PAF) induced platelet aggregation, 5-HT release and intra-platelet free calcium concentration. METHODS: The rate of washed rabbit platelet (WRP) aggregation was measured by turbidimetry and O-phthaldialdehyde (OPT) fluoro-spectrophotometry (FSPM) was used to determine 5-HT content. The intraplatelet free calcium concentration was measured with Fura-2/AM FSPM assay. RESULTS: Rutin in vitro was concentration-dependently inhibiting PAF (9.55 x 10(-9) mol/L) induced WRP aggregation, the IC50 of 5-HT release was 0.73, 1.13 mmol/L respectively and the intraplatelet free calcium concentration elevation evoked by PAF (4.78 x 10(-10) mol/L) were inhibited by 68.3, 136, 274, 545 mumol/L of rutin dose-dependently. CONCLUSION: Rutin could inhibit PAF induced platelet aggregation, 5-HT release and the increase of intraplatelet free calcium.

Animals↗

PubMed2002

[Determination of isoniazid in blood and urine samples by reversed-phase high performance liquid chromatography].

For the purpose of more accurate and rapid analysis of isoniazid in body fluid samples, a reversed-phase high performance liquid chromatographic (HPLC) method was developed. Vanillin, being as a derivatizing reagent, was added to the plasma and urine samples when they were pretreated. Isoniazid and vanillin reacted to form isonicotinoyl hydrazone which was separated and detected. The pretreatment method of sample, the linear range, the precision, and the recovery of isoniazid were investigated by using human's plasma and urine spiked with standard isoniazid. The linear range was 0.2 mg/L- 12.0 mg/L (for plasma, r =0.999 6; for urine, r = 0.999 4). The detection limit was 0.2 mg/L. The intra-day and inter-day precisions of assay for isoniazid were 2.3% - 2.6% and 3.8% - 4.0% (n = 5) for plasma, 1.3% - 4.0% and 2.1% - 3.9% (n = 5) for urine respectively. The average recoveries of isoniazid were from 96.5% to 99.8% in plasma and from 96.3% to 99.4% in urine. The HPLC method has been used to investigate the concentration of isoniazid in the volunteer's plasma. The quantitative analysis of isoniazid in plasma was not interfered by impurities, the metabolites of isoniazid and the derivatizing reagent residue. This analytical method for isoniazid is sensitive, rapid and convenient. It is suitable for the analysis of toxics in forensic samples, the detection of drug concentration in clinical medicines and pharmacokinetic studies.

Antitubercular Agents↗

PubMed1999

Inducible Expression of bcl-2 Antisense RNA Promotes Apoptosis of Human Gastric Cancer Cell Line.

A lot of molecular biological techniques was used to observe the effect of bcl-2 antisence RNA on human gastric cancer cell line SGC7901 and to detect the inducibility and promotion of MT-II promoter. The results showed that MT-II promoter could be activated by the induction with 160 &mgr;mol/L Zn(2+) and the expression of Bcl-2 plays an important role in apoptosis of SGC7901 cells.

Journal Article↗