Inhibition of tumor-induced edema by antisense VEGF is mediated by suppressive vesiculo-vacuolar organelles (VVO) formation.

Vascular endothelial growth factor (VEGF) is an important regulator of angiogenesis, vasculogenesis and vascular permeability. Edema in glioma tumors is considered one of the most pathological characteristics, but the mechanism of regulating vascular permeability is still unclear. In the present study, tumorigenic mice were generated by subcutaneous injection of glioma cell lines, C6-null cells and stable transfected-C6 cells overexpressing mock vector (C6-mock) and antisense VEGF (C6-VEGF(-/-)). Overexpression of antisense VEGF (C6-VEGF(-/-) mice) significantly suppressed tumor growth, decreased angiogenesis and reduced tumoral edema. Further studies by electron microscope revealed that tumor-induced hyperpermeability was mediated by formation of vesiculo-vacuolar organelles (VVO), specifically reducing the number of vesicle and caveolae in VVO, and this effect was blocked, at least partially, by antisense VEGF. These data show a possible mechanism of tumor-induced hyperpermeability and indicate that blockage of VEGF might contribute to therapeutical strategies for tumor edema.

[The changes of gene expression in multiple myeloma treated with thalidomide].

OBJECTIVE: To investigate the effect of thalidomide on bone marrow cells gene expression in multiple myeloma (MM) patients with suppression subtractive hybridization (SSH) and explore the molecular mechanism of thalidomide therapy for MM. METHODS: In a MM patient receiving thalidomide therapy and bone marrow cell from himself, total RNA extraction, mRNA isolation and cDNA synthesis were carried out respectively with routine procedures. SSH were performed in A and B group respectively. The subtracted cDNA was selectively amplified by suppression PCR. The product was inserted into T vector, and then transfected into the competent host JM109. So two subtractive libraries were constructed. After blue-white screening, colonies were selected and plasmids extracted. Homologous comparation was conducted in GenBank. RESULTS: In group A, seven clones were isolated, including ribosomal protein L19 (HUMAN), IgG lambda chain v-v region (HUMAN), contains Alu repetitive element, NADH-ubiquinone oxidoreductase chain 2, elongation factor 1-gamma, human beta globin region, and 40S ribosomal protein S4 (HUMAN). In group B, six clones were isolated, including cytochrome B, up-regulated by 1,25-dihydroxyvitamin D(3) (VDUP1), NADH- ubiquinone oxidoreductase 20 Kd subunit, mu-calpain large subunit, tumor protein, translationally-controlled 1 (TPT1) and COATOMER alpha subunit. CONCLUSION: Thalidomide induces apoptosis and antiangiogenesis by down-regulating some genes and up-regulating some others genes.

[Application of fetal DNA in maternal plasma for non-invasive prenatal diagnosis of fetal sex].

To investigate the feasibility and possibility of application of fetal DNA from maternal plasma for noninvasive prenatal diagnosis of fetal sex, plasma DNAs in blood samples of 73 pregnant women at the gestational period of 26 to 41 weeks were extracted by column separation and nested polymerase chain reaction were employed to amplify the SRY gene. A comparison was made between the amplification results and the real sex of the fetus after their delivery. The concordance rate of SRY gene amplification results of plasma free DNA with real fetal sex was 91.78% (67/73), the sensitivity rate was 97.37% (37/38), and the specific rate was 85.71% (30/35). The cell-free fetal DNA in maternal blood can be one of the valuable material sources for noninvasive prenatal diagnosis and the method of nested PCR could be useful for fetal sex determination. The specific rate of the test was 91.78%. It is of significance to prevent sex-linked inheritant diseases.

[Genetic polymorphisms of five STR loci on chromosome 21 in Chinese Han population].

To elucidate the genetic polymorphisms of five STR loci on chromosome 21 in Chinese Han population and construct a preliminary database, EDTA-blood specimens were collected from unrelated individuals in Beijing. The DNAs were extracted with Chelex method and were amplified by PCR. The PCR products were analyzed by the PAG electrophoresis or by the approach of the automated fluorescent detection. The five STR loci consist of simple repeat motif and its distributions of genotypes are agreement with Hardy-Weinberg equation. Its polymorphism information content is all over 0.50. The obtained data can not only be used as evidences for genetic diagnosis of Down Syndrome, but also for calculating the probabilities in the paternity test and individual identification.

MMTCA recognition by molecular imprinting in interpenetrating polymer network hydrogels based on poly(acrylic acid) and poly(vinyl alcohol).

A novel IPN hydrogel designed to recognize MMTCA is prepared by applying the molecular-imprinting method. The IPN is characterized by FT-IR, DSC, and SEM. Langmuir analysis shows that an equal class of adsorption is formed in the hydrogel. The adsorption equilibrium constant and the maximum adsorption capacity are evaluated, and the effect of the pH on MMTCA adsorption is discussed. The selectivity of the imprinted polymer for MMTCA is studied in aqueous solutions of MMTCA/aspirin/riboflavin. The results suggest that the MMTCA-imprinted polymer shows superior selectivity for MMTCA as compared to riboflavin and aspirin. The reproducibility of the imprinted polymer to MMTCA is also studied.