镉胁迫对冬小麦根端细胞超微结构的影响

用透射电镜观察镉处理对冬小麦幼苗根端细胞超微结构的影响，结果表明，ＣｄＣｌ２２．５Ｈ２Ｏ浓度较低时（１０×１０＾－６），可见被观察的细胞表现为核膜凹陷，胞核变形，染色质稍显凝聚；同样浓度下线粒体的超微结构未见明显变化。ＣｄＣｌ２ ２．５Ｈ２Ｏ浓度较高时（８０×１０＾－６），则见细胞核膜破裂。崩解，染色质显著凝聚；线粒体内膜解体，嵴模糊或消失，表现为不可逆转性变化。     

Relationship of Integrins and Hepatocellular Carcinoma(HCC) Cells during Invasion and Metastasis

This is the first key step of carcinoma cells attachment to the extracellular matrix (ECM), which is mediated by the special receptors of cell's exterior. Integrins belong to the most important attachment molecular. A brief review on hepatocellular carcinoma (HCC) cells' integrins & ECM pertinent during invasion and metastasis is given. The recognition of integrins mediating HCC cell-cell adhesion & HCC cells attachment to ECM and integrins' expression during chemotaxis helps us to understand the significant role of integrins during the whole process. The integrins relate to the process of HCC' invasion and metastasis. People are looking forward to anti-integrins so as to interdict or weaken the reciprocity between integrins & ligands, which must bring aspiring effect to the research on anti-cancer medicine.     

山羊乳腺上皮细胞的光镜观察

采用电穿孔转化法,将EGFP(增强型绿色荧光蛋白)基因转化体外培养的山羊乳腺上皮细胞。细胞穿孔转化7d后在荧光显微镜下观察。结果显示,EGFP基因成功地转入体外培养的山羊乳腺上皮细胞,EGFP基因获得表达,6种电穿孔参数的转化效果基本相同。     

沙棘的花芽分化及花器发育进程研究

利用光学显微镜对中国沙棘花芽分化及花器发育进程进行观察研究,结果表明:沙棘花芽分化分为花芽分化开始期、花序分化期、花蕾分化期、花萼分化期、雄蕊分化期、雌蕊分化期。花粉性细胞的发育经过花粉母细胞、二分体、四分休、单核花粉粒、双核花粉粒几个阶段。胚囊发育包括孢原阶段、四分孢子、经减数分裂,形成成熟胚囊等几个阶段。该研究为合理制定沙棘的栽培技术措施和培育新品种提供了科学依据。     

Phosphoproteomics to analyze PTPLAD1-regulated tyrosine-phosphorylated proteins in colon cancer cells

AIM: To identify and analyze tyrosine-phosphorylated proteins regulated by protein tyrosine phosphatase-like A domain containing protein 1 (PTPLAD1) in colon cancer cells by phosphoproteomics. METHODS: The expression of PTPLAD1 in colon cancer cell line HCT-116 was knocked down by small interfering RNAs, and the differential expression of tyrosine-phosphorylated proteins in response to the konckdown of PTPLAD1 in HCT-116 cells was identified by stable isotope labeling with amino acid in cell culture (SILAC), coupled with the tyrosine phosphorylation antibody immunoprecipitation and LC-MS/MS analysis. The Ingenuity Pathway Analysis (IPA) software was employed for bioinformatics analysis on the differentially-expressed proteins. RESULTS: A total of 20 differentially-expressed tyrosine-phosphorylated proteins were identified by MS, including 8 markedly up-regulated and 10 evidently down-regulated proteins. IPA software suggested that these proteins were mainly associated with the disease of cancer, tissue development and function, and cell death and survival. CONCLUSION: We successfully identified PTPLAD1-regulated differentially-expressed tyrosine-phosphorylated proteins in colon cancer cell line HCT-116. Our analysis suggests that PTPLAD1-regulated proteins in colon cancer are closely correlated with colon cancer.     

Effects of iPSC-MSCs on mitochondria of PC12 cells injured by CoCl2

AIM: To investigate the effects of induced pluripotent stem cells-derived mesenchymal stem cells (iPSC-MSCs) on cobalt chloride (CoCl₂)-induced injuries of PC12 cells and its possible mechanism. METHODS: PC12 cells were exposed to CoCl₂ to set up a chemical-induced cellular injury model and were cocultured with iPSC-MSCs. The cell viability was tested by CCK-8 assay. The apoptosis was measured by flow cytometry using Annexin V/PI staining. The mitochondrial membrane potential (MMP) was analyzed by flow cytometry using JC-1 staining. Immunofluorescence was employed to observe mitochondrial transfer from iPSC-MSCs to PC12 cells. RESULTS: Apoptosis of PC12 cells was increased and MMP of PC12 cells was decreased after exposed to CoCl₂ at concentration of 400 μmol/L for 24 h. Coculture of PC12 cells with iPSC-MSCs reduced the apoptosis and recovered the MMP of the PC12 cells. Tunneling nanotubes were formed between iPSC-MSCs and PC12 cells, through which the iPSC-MSCs transferred the mitochondria to the PC12 cells. CONCLUSION: iPSC-MSCs protect PC12 cells from CoCl₂-induced injuries, which may be associated with the mitochondrial transfer from iPSC-MSCs to PC12 cells.     

Influence of histone deacetylase inhibitor romidepsin on phenotype and function of T lymphocytes in vitro

AIM: To explore the effects of romidepsin (FK228), a novel histone deacetylase inhibitor, on the effector and regulatory T cells in vitro.METHODS: As the reactive cells, lymphocytes, CD4⁺ T cells and CD8⁺ T cells were labelled with CFSE, and stimulated with anti-CD3 and anti-CD28 mAbs in the presence and absence of different levels of romidepsin (experimental group and positive control group), or PBS (placebo group).After 72 h, the proliferation of the cells was detected in different groups. The lymphocytes were stimulated with anti-CD3 and anti-CD28 mAbs in the presence and absence of different levels of romidepsin (experimental group and positive control group),or PBS (placebo group). After 72 h, the percentage of CD4⁺ Foxp3⁺ T cells and the levels of related cytokines were detected in different groups. RESULTS: The proliferation of CFSE-labelled lymphocytes, CD4⁺ T cells and CD8⁺ T cells triggered by anti-CD3 and anti-CD28 mAbs all were inhibited when cultured with romidepsin at concentrations of 1 μmol/L, 3 μmol/L and 5 μmol/L in a dose-dependent manner (P<0.05). Compared with placebo group, in the presence of anti-CD3 and anti-CD28 mAbs, 1 μmol/L romidepsin did not increase the percentage of CD4⁺ Foxp3⁺ T cells (P>0.05). When cultured with romidepsin at concentrations of 3 μmol/L and 5 μmol/L, the percentage of CD4⁺ Foxp3⁺ T cells was enhanced markedly (P<0.05). The levels of IL-10 and TNF-α in the supernatant were markedly increased in positive control group and 3 experimental groups (P<0.05), and the levels of cytokines in different experimental groups were gradually decreased with the elevation of FK228 concentration (P<0.05). The level of TGF-β was slightly increased in positive control group with no significant difference compared with placebo group (P>0.05). With the increase in the concentration of FK228 in different experimental groups, the TGF-β level was increased in a dose-dependent manner and there were significant differences in the 3 experimental groups. Meanwhile, significant differences existed between experimental groups and placebo group and between experimental groups and positive control group (P<0.05). CONCLUSION: Romidepsin inhibits the proliferation of CD4⁺ and CD8⁺ effector T cells and increases the percentage of CD4⁺ Foxp3⁺ regulatory T cells. It may be related to the increased level of TGF-β, but independent of IL-10.     

Injury effect of recombinant soluble human CD40 ligand on human umbilical vein endothelial cells

AIM: To investigate the damage in human umbilical vein endothelial cells (HUVECs) induced by recombinant soluble human CD40 ligand (rshCD40L). METHODS: The cultured HUVECs were treated with rshCD40L for 12 h. The survival activity of the HUVECs was observed by MTS assay. The expression of E-selectin, intercellular adhesion molecule (ICAM)-1, tissue factor (TF) and tissue factor pathway inhibitor (TFPI) was measured by ELISA. The activity of superoxide dismutase (SOD) and the level of malondialdehyde (MDA) were detected by the methods of thibabituric acid (TBA). RESULTS: Compared with normal group, different concentrations of rshCD40L (0.5, 1, 2, 3 mg/L) had no obvious effect on the survival activity of the HUVECs (P>0.05). rshCD40L at concentration of 0.5 mg/L promoted the secretion of E-selectin, sICAM-1, TF and TFPI in the HUVECs (P<0.01). rshCD40L at concentration of 0.5 mg/L also increased MDA content and reduced the activity of SOD in the HUVECs (P<0.05). CONCLUSION: 0.5~3mg/L rshCD40L has no obvious effect on endothelial cell survival, but already causes endothelial dysfunction by increasing endothelial inflammation and exogenous coagulation reaction, inducing lipid peroxides injury and reducing antioxidant capacity.     

Effect of DEC1 gene over-expression on proliferation and invasion abilities of human esophageal cancer ECA109 cells

AIM: To investigate the effect of DEC1 gene over-expression on the proliferation and invasion abilities of human esophageal cancer ECA109 cells.METHODS: ECA109 cells were transfected with plasmid pcDNA3.1 (-)/DEC1 (DEC1 group) or pcDNA3.1 (-) (vector group). The mRNA and protein levels of DEC1, cyclin D1 and MMP-9 were evaluated by real-time PCR and Western blot, respectively. The effects of DEC1 over-expression on the proliferation and invasion abilities of the ECA109 cells were evaluated by CCK-8 assay, colony formation assay and Transwell test respectively.RESULTS: The DEC1 expression level in ECA109 cells in DEC1 group was significantly higher than that in vector group (P<0.01), but the levels of MMP9 and cyclin D1 expression were opposite (P<0.01). However, both the proliferation and invasion abilities of ECA109 cells in DEC1 groups decreased significantly as compared with those in vector group (P<0.05).CONCLUSION: The over-expression of DEC1 significantly inhibits the proliferation and invasion of ECA109 cells, which may be involved in the expression of cyclin D1 and MMP9.     

MSC-conditioned medium activates Nrf2/ARE pathway to protect H9c2 cells against oxidative stress

AIM: To investigate the protective effect of mesenchymal stem cell (MSC)-conditioned medium (MSCCM) on myocardial cell line H9c2 and its mechanism. METHODS: Verification of MSC was performed by flow cytometry analysis, followed by MTT assay to determine the optimal incubation time of MSCCM with myocardial cells. The cells were divided into 4 groups: normal (N) group, model (M) group, M+MSCCM group and MSCCM group. The cells in M+MSCCM group and MSCCM group were pre-incubated with MSCCM for 24 h. The cells in M group and M+MSCCM group were treated with 300 μmol/L H₂O₂ for 4 h to imitate oxidative injury of myocardial cells. Mitochondrial membrane potential and apoptotic rate of injured myocardial cells were detected by flow cytometry. The ROS production was measured by fluorescence microscopy. The nuclear translocation of Nrf2 and expression of HO-1 was examined by Western blot. RESULTS: No difference of mitochondrial membrane potential, apoptotic rate or ROS production between MSCCM group and N group was observed (P>0.05). The mitochondrial membrane potential depolarization, apoptotic rate and ROS production in M+MSCCM group were significantly lower than those in M group (P<0.01). The nuclear translocation of Nrf2 and expression of HO-1 in the myocardial cells were increased with MSCCM incubation time prolonged. CONCLUSION: MSCCM protects the myocardial cells against oxidative injury induced by H₂O₂. The anti-oxidative mechanism would be associated with the activation of Nrf2/ARE pathway.