ObjectiveTo review the characteristics of human defensin 5 (HD-5), including molecular structure, antibacterial activity and gene expression, and to show its development prospect as a new drug in the treatment of enterogenic infection. MethodsThe published papers about HD-5 were reviewed to summarize its research progress. ResultsBeing a 3-5 KDa cationic peptide rich in cysteine and arginine, especially without glycosylated side-chain, HD-5 plays its antibacterial role against positive and negative Gram’s bacterium, fungi, spirochete, protozoan and enveloped virus with the special active center composed of three disulfide bonds. HD-5 encoding gene alpha defensin 5 (DEFA5) localizes at the 8th chromosome P21-pter with 449 bp, which includes five pieces of sequence: 5′ untranslated region (1-40)，signal peptide (41-97), propiece (98-226), mature peptide (227-322)，and Poly A (433-438).ConclusionAs a broad-spectrum and effective endogenous antimicrobial peptide, HD-5 would be a promising alternative peptide against enterogenic infection if the accessibility to its mass production is settled.
Five fresh human forearms removed from cadavers were used to study the vascular concentration of the flexor digital tendons by stereology method. The results showed: (1) The Vv is 0.45%, and Lv is 1.9; (2) The vascular concentration of the flexor digital tendons of different fingers showed no significance statistically; (3) The vascular concentration of the tendons within the digital sheath was less than that outside the digital sheath (plt;0.01); (4) The vascular concentration of the tendons were decreasing gradually form the thum dto litter finger.
ObjectiveTo explore the effects of exogenous estrogen receptor β1 (ERβ1) gene on the expression of human telomerase reverse transcriptase (hTERT) as well as the changes of proliferation ability in MDA-MB-231 cell line by transfecting recombinant eukaryotic expressing vector containing ERβ1 cDNA into human breast cancer MDA-MB-231 cell. MethodsRecombinant eukaryotic expressing vector containing ERβ1 cDNA was transfected into human breast cancer MDA-MB-231 cell by using cationic liposome as transfecting agent (acted as pcDNA3.1ERβ1 transfection group), empty vector group and non-transfection group acted as controls. The expression levels in both the mRNA and protein of both the ERβ1 and hTERT were tested by real-time PCR and Western blot, respectively. The change of proliferation ability in MDA-MB-231 cell was displayed by cell growth curve, and the change of cell apoptosis was detected by flow cytometry. ResultsThe expression level of ERβ1 mRNA in the pcDNA3.1-ERβ1 transfection group (0.449±0.077) significantly increased as compared with the nontransfection group (0.153±0.035) or the empty vector group (0.160±0.020), P=0.001 or P=0.000. The expression level of ERβ1 protein in the pcDNA3.1-ERβ1 transfection group (0.847±0.065) significantly increased as compared with the non-transfection group (0.356±0.050) or the empty vector group (0.390±0.030), P=0.001 or P=0.000. The expression level of hTERT mRNA in the pcDNA3.1-ERβ1 transfection group (0.127±0.020) significantly decreased as compared with the non-transfection group (0.283±0.025) or the empty vector group (0.283±0.049), P=0.001 or P=0.002. The expression level of hTERT protein in the pcDNA3.1-ERβ1 transfection group (0.147±0.023) significantly decreased as compared with the non-transfection group (0.783±0.025) or the empty vector group (0.802±0.019), P=0.001 or P=0.002. The rate of cell apoptosis in the pcDNA3.1-ERβ1 transfection group 〔(6.15±0.94)%〕 was higher than that in the non-transfection group 〔(1.41±0.42)%〕， P=0.001. Cell proliferation curve showed that proliferation ability significantly decreased in the pcDNA3.1-ERβ1 transfected groups as compared with the non-transfection group (Plt;0.05). ConclusionERβ1 could inhibit cell growth of human breast cancer MDA-MB-231 cell by down-regulating the expression of hTERT.
Objective To investigate the memory amelioration of the Alzheimer disease (AD)model rat after being transplanted the single neural stem cells(NSC) and NSC modified with human brain-derived neurotrophic factor（hBDNF） gene. Methods Forty SD rats were divided evenly into 4 groups randomly. The AD model rats were made by cutting unilaterallythe fibria fornix of male rats. Ten to twelve days after surgery, the genetically modified and unmodified NSC were implanted into the lateral cerebral ventricle of group Ⅲ and group Ⅳ respectively. Two weeks after transplantation, theamelioration of memory impairment of the rats was detected by Morris water maze. Results The average escaping latency of the group Ⅲ and group Ⅳ (41.84±21.76 s,25.23±17.06 s respectively) was shorter than that of the group Ⅱ(70.91±23.67 s) (Plt;0.01). The percentage of swimming distance inthe platform quadrant in group Ⅲ (36.9%) and in group Ⅳ(42.0%) was higherthan that in the group Ⅱ(26.0%) (Plt;0.01). More marginal and random strategies were used in group Ⅱ.The percentage of swimming distance in the platform quadrant in group Ⅳ was also greater than that in group Ⅲ(Plt;0.05). There were no significant differences in the average escaping latency, the percentage of swimming distance in the platform quadrant and the probe strategy between group Ⅳ and group Ⅰ(Pgt;0.05).More lineal and oriented strategies were used in group Ⅳ. Conclusion The behavioral amelioration of AD model rat was obtained by transplanting single NSC and hBDNF-gene-modified NSC. The effect of the NSC group modified with hBDNF gene is better than that of the groupⅢ.
Objective To investigate the method and conditions of isolation，proliferation of multipotent mesenchymal stem cells（MSCs）from human umbilical cord blood in vitro, and to induce osteogenic and adipogenic differentiation directly for identification. Methods Human umbilical cord blood was collected in asepsis condition, isolated by density gradient centrifugation,or sedimented red cell with methylcellulose, and then the same centrifugation was done, or obtained by negative immunodepletion of CD34+. These isolated mononuclear cells were used to carry on plastic adherent culture. To obtain single cellderived colonies, these cells were proliferated clonally in medium which consists of L-DMEM orMesencultTM medium and 10% fetal calf serum（FCS） respectively, then their differentiation potentiality to osteoblasts and lipoblasts was tested. Results The mononuclear cells isolated by sedimented and centrifugated way cultured in MesencultTM medium and 10%FCS were most available. These adhesive cells could become obviously short rodshape or shuttle-shape cells after 5-7 days.The colonies form well in 3rdpassage cells. The mononuclear cells obtained by onlycentrifugalized in density gradient were hard to form colony, isolated by immunomagnetic beads were hard to culture. The surface antigens of these colonies cells presented CD29, CD59, CD71 but not CD34,CD45 and HLADR etc. The colony cells differentiating into osteoblasts that produce mineralized matrices, stained by alizarin red, and differentiating into adipocytes that accumulate lipid vacuoles, stained by oil red. Conclusion MSCs can be isolated from human umbilical cord blood and proliferate it in vitro. The way that mononuclear cells are sedimented red cell by methylcellulose and cultured by MesencultTM medium and 10% FCS is the valid method of isolation. Proliferation colonies cells present matrix cell immunophenotypes, and candifferentiate into osteoblasts and adipocytes.
OBJECTIVE This paper was to study the biological characteristics of the transformed human embryonic tendon cells, the relation between cell growth and culture conditions, and to compare these features with that of human embryonic tendon cells. METHODS The pts A58H plasmid had successfully used to transform a tendon cell line from human embryo in our past work. The human embryonic tendon cells and the transformed human embryonic tendon cells were cultured in vitro. In different culture conditions, the growth curve were drawn respectively. Population dependence and proliferation capability of the cells were investigated through plate cloning test and soft agar culture. The collagen secreted by cells was identified by immunohistochemical method. RESULTS In routine culture condition, the growth properties of the human embryonic tendon cell and transformed cells were almost identical. The growth properties of the transformed cells were not changed when the cells were frozen storage. There were changes of growth characteristics of the transformed cells when the culture temperature was changed. The transformed cells could subcultured continually and permanently. The proliferation capability of the transformed cells were ber than that of the human embryonic tendon cells. Moreover, the growth of the transformed cells was serum-dependent, and the phenomenon of contact inhibition was observed. The transformed cells were not able to grow on soft agar culture. They had the capacity of secreting collagen type I. CONCLUSION The transformed human embryonic tendon cells could be subcultured continually and permanently, and their growth could be controlled by changing their culture conditions and they had no malignant tendency in biological characteristics. They could be taken as an ideal experimental material for tendon engineering.
OBJECTIVE: To construct a plasmid which has a reporter gene for exploring the role of human telomerase reverse transcriptase(hTRT) in in-vitro cell cultivation. METHODS: hTRT was cut by restricted enzyme from plasmid pGRN145 and inserted to plasmid pEGFP-C1 (enhanced green fluorescent protein). RESULTS: Restricted enzyme analysis and DNA sequencing showed that the sequence of the pEGFP -hTRT transgenic plasmid was correct. CONCLUSION: The recombinant vector pEGFP-hTRT has been successfully constructed, and it can be used as a transgenic plasmid in generating immortalized cell lines.
Objective To establ ish a new induction method from human embryonic stem cells (hESCs) differentiating into hepatocyte-l ike cells using an adherent culture system with single-step induction. Methods Undifferentiated hESCs were cultured on Matrigel-coated culture plates for 4 days, hepatic differentiation was initiated at 60%-70% confluence by adding Activin A for 5 days. Then the induction medium was replaced by hepatocyte induction medium (HIM) supplemented with fibroblast growth factor 1 (FGF-1) and bone morphogenetic protein 4 (BMP-4) for another 6 days. Finally, the cells were treated with HIM adding hepatocyte growth factor (HGF) and Oncostatin M (OSM) for 5-7 days. The characteristics of differentiated cells were determined by morphology, immunofluorescence staining, RT-PCR, and Periodicacid- Schiff (PAS) test. Results Differentiated cells treated with Activin A, FGF-1, BMP-4, HGF, and OSM sequentially were morphologically larger and became spherical, oval or polygon. Some cells had 2 or 3 nuclei, suggesting that the cells have a hepatocyte-l ike morphology. Differentiated cells at first induction stage could be stained positive by SOX17 and Forkhead (FOX)A2 after induction by Activin A. Then they turned to be α fetoprotein (AFP) and α1 antitripsin positive cells at second induction stage after induction by FGF-1 and BMP-4. Finally, the differentiated cells treated with HGF and OSM showed PAS possitive for glycogen detection. The differentiated cells at various stages also expressed at early (SOX17, FOXA2, and GATA-4),middle (AFP, albumin, and cytokeratin 18), and mature (alcohol dehydrogenase 1C and Cytochrome P4501B1) stage hepatic genes, respectively. Conclusion Using a simple-step induction method and by suppl ied with cytokines consequently, hESCs can be induced to differentiate into hepatocyte-l ike cells. The differentiation method can provide seed cells for hepatic tissue engineering or cell-therapy.
ObjectiveTo study the mechanism of reducing the intratumoral microvessel density (MVD) by Ginsenoside Rg3 (Rg3) combined with cytotoxic agent in xenotransplanted human breast infiltrating duct carcinoma in nude mice. MethodsSixteen female nude mice were randomly divided into 4 groups to receive cyclophosphamid (16 mg/kg,qd) combined with Rg3 (10 mg/kg, qd),Rg3(10 mg/kg,qd) alone,cyclophosphamid (16 mg/kg,qd) alone and 0.5% sodium carboxymethyl cellulose (0.5 ml,qd) respectively for 55 days. Breast cancer mass were weighed and sampled for light microscopic observation. The intratumor MVD was examined by immunohistochemical staining. ResultsThe tumor weight of treated group was significantly lower than that of control group. The tumor weight of the Rg3 combined with CTX group was lower than that of Rg3 group. The MVD value of Rg3 group was significantly lower than that of CTX group and control group. The MVD was significantly reduced in the Rg3 combined with CTX group than that in the others.ConclusionRg3 combined with CTX can inhibit the growth of xenotransplanted human breast infiltrating duct carcinoma, and reduce the intratumoral MVD.
To evaluate the biological tolerance of the human liver to prolonged warm ischemia, 20 patients who underwent liver resections with hepatic inflow occlusion are reported. Biopsy of liver were performed during and after consecutive periods of hepatic ischemia, and speciments were observed under light and electron microscope. The results showed that hepatic vascular occlusion for ＜30 min, resulted in atotissular temporary but reversible pathologic and ultrastructural changes in liver, even patients with liver cirrhosis had better recovery from the operation when the hepatic ischemia was lengthen up to 40 min.