In vitro calcium deposition by rachitic rat matrix vesicles: nucleoside triphosphate supported calcium deposition.

The present study was designed to test whether ATP at serum levels can support matrix vesicle-mediated Ca deposition while the final Ca x P ion product is maintained at or below serum or cartilage fluid levels. Rachitic rat epiphyseal cartilage matrix vesicles (40 micrograms protein/ml) in a simple calcifying solution (without exogenously added Pi) containing 50 mM Tris, pH 7.6 at 37 degrees C, 0.1 M NaCl, 1.35 mM CaCl2, 1 mM ATP, deposited about 500 nmol Ca/mg protein after 5 h. The amount of Ca deposited increased with increases in incubation time, concentrations of ATP, Ca2+, hydroxide, and matrix vesicle protein. UTP, GTP, and CTP were equally effective in supporting Ca deposition by matrix vesicles. ATP-alpha,beta-methylene and ATP-beta,gamma-methylene were inhibitory for ATP-dependent Ca deposition. Experiments with limiting amounts of ATP and Ca2+ available in the calcifying solution indicated that ATP concentration at serum levels, in the presence of Ca x P ion products at serum or cartilage fluid levels, can support matrix vesicle-mediated Ca deposition.     

Identification of a high molecular weight nervous system specific cell surface glycoprotein on murine neuroblastoma cells

An antiserum to N18 neuroblastoma cells has been used to identify a glycoprotein of apparent molecular weight greater than 200 000 D in SDS-polyacrylamide gels. This glycoprotein (Band 1) is found in culture medium of N18 cells. An immunologically similar component can be immunoprecipitated from detergent extracts of enzymatically iodinated or biosynthetically labelled viable cells. Anti-band 1 activity can be adsorbed from the antiserum by intact N18 cells but not four other cultured murine cell lines. Normal adult murine brain also adsorbs anti-band 1 activity but adult murine adrenal, heart, kidney, liver, lung, and spleen do not. Several experiments indicate that band 1 is not myosin heavy chain or the fibroblast LETS protein. Thus band 1 is a newly identified high molecular weight nervous system specific glycoprotein.     

Effects of sodium intake on renal cortical blood flow distribution.

Renal cortical blood flow and superficial cortical blood flow were measured in chronic sodium-loaded, sodium-deprived and normal rats. Neither total renal cortical blood flow was different among the three groups of animals. Alterations in the amount of sodium excreted, therefore, are not related to alterations of renal cortical blood flow distribution.     

Differential rates of sister chromatid exchanges between euchromatin and heterochromatin

In two rodent species, the Chinese hamster and the montane vole (Microtus montanus), the rate of sister chromatid exchange was lower in constitutive heterochromatin than in euchromatin.     

Measurement of renal blood flow in the rat.

The radioactive microsphere technique is a simple method for measurement of RBF and intrarenal blood flow distribution in the rat that does not require surgical manipulation of the kidney or general anesthesia. The results are reproducible and compatible with other established techniques.     

Effects of Luteolin on Human Breast Cancer Using Gene Expression Array: Inferring Novel Genes

Taraxacum officinale (dandelion) is often used in traditional Chinese medicine for the treatment of cancer; however, the downstream regulatory genes and signaling pathways mediating its effects on breast cancer remain unclear. The present study aimed to explore the effects of luteolin, the main biologically active compound of T. officinale, on gene expression profiles in MDA-MB-231 and MCF-7 breast cancer cells. The results revealed that luteolin effectively inhibited the proliferation and motility of the MDA-MB-231 and MCF-7 cells. The mRNA expression profiles were determined using gene expression array analysis and analyzed using a bioinformatics approach. A total of 41 differentially expressed genes (DEGs) were found in the luteolin-treated MDA-MB-231 and MCF-7 cells. A Gene Ontology analysis revealed that the DEGs, including AP2B1, APP, GPNMB and DLST, mainly functioned as oncogenes. The human protein atlas database also found that AP2B1, APP, GPNMB and DLST were highly expressed in breast cancer and that AP2B1 (cut-off value, 75%) was significantly associated with survival rate (p = 0.044). In addition, a Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the DEGs were involved in T-cell leukemia virus 1 infection and differentiation. On the whole, the findings of the present study provide a scientific basis that may be used to evaluate the potential benefits of luteolin in human breast cancer. Further studies are required, however, to fully elucidate the role of the related molecular pathways.     

Resistin induces monocyte-endothelial cell adhesion by increasing ICAM-1 and VCAM-1 expression in endothelial cells via p38MAPK-dependent pathway

Resistin, firstly reported as an adipocyte-specific hormone, is suggested to be an important link between obesity and diabetes. Recent studies have suggested an association between resistin and atherogenic processes. The adhesion of circulating monocytes to endothelial cells is a critical step in the early stages of atherosclerosis. The purpose of the present study was to investigate the effect of resistin on the adhesion of THP-1 monocytes to human umbilical vein endothelial cells (HUVECs) and the underlying mechanism. Our results showed that resistin caused a significant increase in monocyte adhesion. In exploring the underlying mechanisms of resistin action, we found that resistin-induced monocyte adhesion was blocked by inhibition of p38MAPK activation using SB203580 and SB202190. Furthermore, resistin increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by HUVECs and these effects were also p38MAPK-dependent. Resistin-induced monocyte adhesion was also blocked by monoclonal antibodies against ICAM-1 and VCAM-1. Taken together, these results show that resistin increases both the expression of ICAM-1 and VCAM-1 by endothelial cells and monocyte adhesion to HUVECs via p38MAPK-dependent pathways.     

Winter spatial distribution of fish larvae assemblages relative to the hydrography of the waters surrounding Taiwan

The aim of this study was to investigate the species composition and distribution of fish larvae in relation to hydrographic conditions in the waters surrounding Taiwan Island (TI) in February 2003. In total, 242 kinds of fish larvae belonging to 127 genera and 75 families were recognized. Among these, 109 taxa were identified to the family or genus level, others to the species level. The 12 predominant types, which constituted 71% of the total fish larvae, were Engraulis japonica, Scomber sp., Diaphus spp., Benthosema pterotum, Carangoides ferdau, Embolichthys mitsukurii, Maurolicus sp., unidentified Myctophidae, Gonostoma gracile, Trichiurus lepturus, unidentified Gobiidae, and Myctophum asperum. The distribution of fish larvae showed a clear association with water masses around TI, with higher abundances and lower species richness northwest of TI where the China Coastal Current prevails, and lower abundances and higher species diversity east of TI where the Kuroshio Current dominates. Cluster analysis distinguished three station groups and four species groups, and the distribution patterns of fish larvae also corresponded to hydrographic conditions. The total abundances of fish larvae and eight of the 12 predominant taxa showed significant and positive correlations with zooplankton abundance, which suggests that food source might be a key factor determining the abundance and distribution of fish larvae during the winter.