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Li-Mei Liu

Publications and source records attributed to Li-Mei Liu.

6 recordsLinked to original sources
PubMed2005

Research progress on Helicobacter pylori outer membrane protein.

Helicobacter pylori (H pylori), one of the most common bacterial pathogens on human beings, colonizes the gastric mucosa. In its 95 paralogous gene families, there is a large outer membrane protein (OMP) family. It includes 32 members. These OMP are important for the diagnosis, protective immunity, pathogenicity of H pylori and so on. They are significantly associated with high H pylori density, the damage of gastric mucosa, high mucosal IL-8 levels and severe neutrophil infiltration. We introduce their research progress on pathogenicity.

Bacterial Outer Membrane Proteins↗
PubMed2005

[Clinical significance of survivin expression in colorectal cancer and its relationship with cell apoptosis and angiogenesis].

BACKGROUND & OBJECTIVE: Expression of survivin, an apoptosis suppressor gene, in colorectal cancer(CRC), and its relationship with pathologic factors, cell apoptosis, and angiogenesis are unclear. This study aimed to investigate the effect of survivin on cell apoptosis, and its relation with angiogenesis, and to further explore the effects of survivin on development and prognosis of CRC. METHODS: Protein expression of survivin, and vascular endothelial growth factor (VEGF) in 91 specimens of CRC was detected by immunohistochemistry, apoptosis index (AI) of tumor cells was detected by TUNEL method. RESULTS: Positive rate of survivin in CRC with distant metastasis was 56.0% (14/25), significantly higher than that in CRC without metastasis (48.5%, 32/66) (P<0.05); and that in 5-year survival patients(42.9%,30/70) was lower than that in patients died within 5 years (76.2%,16/21) (P<0.01). The average survival time of patients with positive expression of survivin was 91.3 months, and that of patients with negative expression of survivin was 116.4 months; 5-year survival rate of the former (65.2%, 30/46) was significantly lower than that of the latter (88.9%, 40/45) (P<0.01). The average AI of patients with positive expression of survivin was lower than that of patients with negative expression of survivin [(0.74+/-0.19)% vs. (1.07+/-0.24)%, P<0.01]; the expression of survivin significantly correlated with that of VEGF (pearson: 0.721). CONCLUSION: Survivin may promote metastasis, and affect prognosis of CRC through inhibiting cell apoptosis, and regulating angiogenesis of CRC.

Adult↗
PubMed2005

[Role of Bcl-xL in the cathepsin D-associated apoptosis of K562 cells].

The purpose of study was to explore the possible functions of Bcl-xL in the glucosamine sulfate-induced apoptosis of chronic myeloid leukemia K562 cells. Light microscopy and Wright-Giemsa staining were used to investigate the morphologic evidences for apoptosis of K562 cells induced by glucosamine sulfate (GS); immunofluorescence was used to observe the translocation of cathepsin D and cytochrome C during the apoptosis; Western blot was performed to detect the expression of Bcl-xL, Bid, Bax in K562 cells treated by GS. The results showed that many vacuoles were observed in the cytoplasma of the K562 cells treated by GS; fluorescent signals of cathepsin D and cytochrome were fransformed from granules to disperse form by using immunofluorescence; the expression of Bcl-xL was found down-regulated in K562 cells treated by GS, but not in the cells pre-treated with pepstatin A; the significant changes were not detected in expression of Bax and Bid protein before or after apoptosis. It is concluded that Bcl-xL protein may mediate relationship between cathepsin D and mitochondia pathway, Cathepsin D may play an important role in the GS inducing apoptosis of K562 cells through downregulation of Bcl-xL expression.

Apoptosis↗
PubMed2005

[Reversion of multidrug resistance in HL-60/VCR cells by down-regulation of bcl-2 with bcl-2 siRNA].

To evaluate the feasibility of gene therapy using bcl-2 as target in multiple drug resistance of leukemia, the small interfering RNA eukaryotic expression vector specific to human bcl-2 gene was constructed by gene recombination, then transfected into HL-60/VCR cells. Stable transfectants were obtained by G418 screening. The growth curve and drug sensitivity were detected by using MTT. The expression of Bax and ZNRD1 was analyzed by Western blot. The results showed that mU6pro-bcl-2 siRNA was successfully constructed and transfected into HL-60/VCR cells. The IC(50) of transfected cells to vincristine and adriamycin was significantly reduced as compared with that of the control. The expression of ZNRD1 in transfected cells was decreased as compared with that of the control, while Bax not. It is concluded that the bcl-2 siRNA restores the sensitivity of HL-60/VCR cells to conventional chemotherapeutic agents to a certain degree.

Blotting, Western↗
PubMed2003

[Role of tumor metastasis suppressor gene KAI1 in development of colorectal cancer].

BACKGROUND & OBJECTIVE: The study of tumor metastasis suppressor gene KAI1 in colorectal cancer (CRC) is limited nowadays. There are some controversies about the expression of KAI1 and its relationship with pathologic classification of CRC, and up today, the reports of the correlation between KAI1 and the prognosis of CRC still be few. This study was designed to investigate the role of KAI1 in development of CRC and its value in predicting the prognosis of CRC. METHODS: The expression of KAI1 in 91 cases of primary CRC and 25 cases of lymph node metastases were determined using immunohistochemistry. RESULTS: The positive cases of KAI1 in primary CRC were 54 (59.3%), the weak positive cases were 22 (24.2%), the negative cases were 15 (16.5%). KAI1 expression reduced significantly in the cases with low differentiation, lymph node metastasis and distant metastatic tumor (P< 0.01). The positive expression rate of KAI1 in the patients who survived more than 5 years (67.14%) was higher than that in the patients who survived less than 5 years (33.33%) (P< 0.05). The 5-year survival rates of the patients with positive, weak positive, and negative expression of KAI1 decreased in turn (87.04%, 63.34%, 60.00%; P< 0.05). KAI1 expression in lymph node metastases was lower than that in primary locus (P< 0.05). CONCLUSION: The abnormal expression of KAI1 participates in malignant progression of CRC. Detecting the expression of KAI1 probably possesses clinical significance in evaluating the differentiation, lymph node metastasis,and distant metastasis of CRC, and predicting the prognosis of CRC.

Adult↗