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Xiao-Mei Zhou

Publications and source records attributed to Xiao-Mei Zhou.

6 recordsLinked to original sources

Monitoring microarray-based gene expression profile changes in hepatocellular carcinoma.

AIM: To find out key genes responsible for hepatocarcinogenesis and to further understand the underlying molecular mechanism through investigating the differential gene expression between human normal liver tissue and hepatocellular carcinoma (HCC). METHODS: DNA microarray was prepared by spotting PCR products of 1 000 human genes including 445 novel genes, 540 known genes as well as 12 positive (housekeeping) and 3 negative controls (plant gene) onto treated glass slides. cDNA probes were prepared by labeling normal liver tissue mRNA and cancer liver tissue mRNA with Cy3-dUTP and Cy5-dUTP separately through reverse transcription. The arrays were hybridized against the cDNA probe and the fluorescent signals were scanned. The data obtained from repeated experiments were analyzed. RESULTS: Among the 20 couple samples investigated (from cancerous liver tissue and normal liver tissue), 38 genes including 21 novel genes and 17 known genes exhibited different expressions. CONCLUSION: cDNA microarray technique is powerful to identify candidate target genes that may play important roles in human carcinogenesis. Further analysis of the obtained genes is helpful to understand the molecular changes in HCC progression and ultimately may lead to the identification of new targets for HCC diagnosis and intervention.

Carcinoma, Hepatocellular↗

[Comparison between two methods for staining DNA of apoptotic spermatozoa].

OBJECTIVE: To compare two fluorochrome staining methods for the assessment of sperm quality. METHODS: Washed sperm cells were incubated in 0, 0.15, or 15 micromol/L camptothecin (CAM), or 0.37 or 3.7 mmol/L genistein (GEN) at 37 degrees C for 4 hours. The sperm cells were analyzed for cycle-independent apoptosis and necrosis by single-stain compared with dual-stain fluorescence microscopy to contrast the relative effectiveness of these two approaches. RESULTS: The single-stain procedure could not detect the sperm viability differences. In contrast, the dual-stain procedure identified a dosage-dependent decrease in the viability and increased necrozoospermia after topoisomerase inhibitor CAM and GEN treatments. Apoptosis was 2-fold higher with topoisomerase inhibitor treatment. CONCLUSION: The two topoisomerase inhibitors were associated with increased apoptosis and dosage-dependent necrosis. The data suggested that the dual-stain combination Hoechst 33342/PI was more sensitive than the single Hoechst 33342 stain analysis and permitted quantitative analysis of the apoptosis and necrosis in sperm.

Apoptosis↗

The physiology constant database of teen-agers in Beijing.

Physiology constants of adolescents are important to understand growing living systems and are a useful reference in clinical and epidemiological research. Until recently, physiology constants were not available in China and therefore most physiologists, physicians, and nutritionists had to use data from abroad for reference. However, the very difference between the Eastern and Western races casts doubt on the usefulness of overseas data. We have therefore created a database system to provide a repository for the storage of physiology constants of teen-agers in Beijing. The several thousands of pieces of data are now divided into hematological biochemistry, lung function, and cardiac function with all data manually checked before being transferred into the database. The database was accomplished through the development of a web interface, scripts, and a relational database. The physiology data were integrated into the relational database system to provide flexible facilities by using combinations of various terms and parameters. A web browser interface was designed for the users to facilitate their searching. The database is available on the web. The statistical table, scatter diagram, and histogram of the data are available for both anonym and user according to queries, while only the user can achieve detail, including download data and advanced search.

Adolescent↗

Influence of inoculum type, inorganic salt and nitrogen to carbon ratio on sclerotium formation and carotenoid production in surface culture of Penicillium sp. PT95.

This study examined the respective effect of inoculum type, inorganic salt and nitrogen to carbon ratio on sclerotium formation and carotenoid production in surface culture of Penicillium sp. PT95. Neither the spore inoculum nor the mycelial pellet inoculum could result in the formation of sclerotium on a modified Czapek agar medium after incubation of 28 days, whereas the inoculum in the form of sclerotium caused the formation of numerous orange, sand-shaped sclerotia after incubation of 14 days. Among four inorganic salts tested, K(2)HPO(4) was more essential to the sclerotium formation and carotenoid production of strain PT95 as compared to KCl, MgSO(4) or FeSO(4). It was also shown that the combination of K(2)HPO(4), KCl and MgSO(4) could produce the best positive cooperation and give the highest sclerotia biomass (782 mg/plate) and carotenoid content in sclerotium (420 microg/g of dry sclerotia) as well as pigment yield (328 microg/plate). The medium containing 0.24 approximately 0.48 g/l sodium nitrate-nitrogen was effective to both the sclerotium formation and carotenoid production of strain PT95 when available maltose-carbon concentrations were at 5.26 approximately 21.05 g/l. The optimal N:C ratio was found to be 1:25.

Biomass↗

Dynamic changes of type I,III and IV collagen synthesis and distribution of collagen-producing cells in carbon tetrachloride-induced rat liver fibrosis.

AIM:To find out the relationship between the gene transcription of different types of procollagen and the deposition of the relevant collagens in the liver tissue and to confirm the types of collagen producing cells in liver fibrogenesis.METHODS:Dynamic changes of the expression of alpha1(I), alpha1(III) and alpha1(IV) procollagen mRNA and relevant collagens and the distribution of collagen producing cells during liver fibrogenesis of rat induced by CCl(4) (20 weeks) were investigated with Northern blot analysis, in situ hybridization and immunohistochemical techniques.RESULTS: The increased expression of alpha 1(III) procollagen mRNA by Northern blot analysis was the most predominant one among the three mRNAs during fibrogenesis. However, the enhanced expression of alpha1(IV) procollagen mRNA occurred very early while the expression of alpha1(I) mRNA was not enhanced much until the middle stage of the experiment. Desmin (Dm) positive hepatic stellate cells (HSCs) and few myofibroblasts (MFs) in and around the necrotic areas expressed alpha1(I), alpha1(III) and alpha1(IV) procollagen mRNA signals detected by in situ hybridization at the early stage of the experiment. All the three procollagen mRNA signals thereafter mainly localized in fibroblasts (Fbs) and MFs in fibrotic septa during the middle and late stages of fibrosis, which distributed parallel to the corresponding collagens detected by immunohistochemical study. In addition, the endothelial cells of sinusoids and the small blood vessels within the septa also showed alpha1(IV) procollagen mRNA and type IV collagen expression.CONCLUSION:It is considered that "HSC-MF-Fb effect cell system is the major cellular source of collagen production in liver fibrosis, in which HSCs are collagen producing precursor cells in the early liver fibrogenesis, thereafter the synthesis of type I, III and IV collagens (Col I, Col III and Col IV) mainly derives from MFs and Fbs, which play a very important role in the progress of liver fibrosis. The endothelial cells along sinusoids, as another source of Col IV production, might participate in the capillization of liver sinusoids.

Journal Article↗