The aims of this study were to compare the proliferation and mineralization ability of CFU-F selected dental pulp cellsderived from primary and permanent teeth. Those cells were isolated by enzyme ...digestion and analyzed for their colonyformingcapacity. The cell proliferation was measured by the MTT assay on day 1, day 7, and day14. Alizarin Red S stainingwas used to detect mineralized nodule formation of the cells on day 7, 14, 21, and 28. Proliferation of CFU-F selected pulpcells from primary teeth was significantly higher than that of CFU-F selected pulp cells from permanent teeth in all periods ofthe experiment. Upon cultured cells in mineralization inducing media, the mineralized nodules appeared as early as day 14 inCFU-F selected pulp cells from primary teeth and MG-63, whereas those of CFU-F selected pulp cells from permanent teethcan be found at day 21. On day 21 and day 28, the mineralized nodules of the CFU-F selected pulp cells from the primaryteeth group were more than those in the CFU-F selected pulp cells from the permanent teeth group. Mineralized noduleformation in the CFU-F selected pulp cells from the permanent teeth group appeared later and were less than those ofCFU-F selected pulp cells from primary teeth. However, mineralized nodules in CFU-F selected pulp cells from the permanentteeth group increased very fast after their appearance. Those results suggest that CFU-F selected pulp cells from primaryteeth had a higher proliferation rate and mineralization rate when compared to CFU-F selected pulp cells from permanentteeth.
Effects of soil compaction on the microbial populations of melon and maize rhizoplane were investigated in quantity and quality. The numbers of culturable bacteria and fluorescent pseudomonads on the ...rhizoplane were higher when plants were grown in more compacted soil and the relative increase was larger in fluorescent pseudomonads. Total bacterial counts, however, did not appear to be affected by soil compaction, resulting in the increase in the culturable bacteria among total counts in more compacted soil. The determination of extracellular enzymatic properties (pectinase, α-glucosidase, ß-glucosidase and α-galactosidase) of each 100 isolates from bulk soil and root samples suggested that the microbial populations on the rhizoplane, especially when plants were grown in highly, compacted soil, were composed of high ratios of bacteria with abilities to utilize root exudates efficiently. The microbial community structure estimated from the colony forming curves of bulk soil and root samples suggested that the microbial populations on the rhizoplane, especially when plants were grown in compacted soil, were likely to be composed of more r-strategists which were defined as those who formed colonies within 2 days.
It remains unknown whether the life span of systemic sclerosis (SSc) skin fibroblasts (FB) and that of normals are the same or not, though SSc skin FB have been shown to present abnormalities such as ...elevated collagen synthesis.
To find out whether the life span of SSc skin FB and that of normals are the same or not.
Cell generation and colony-forming efficiency were calculated in 10 normal and 7 SSc FB, and total life spans were studied.
Colony-forming efficiency decreased from 30 to 5% until the cells reached senescence. The cell generations of normal and SSc FB showed no significant difference.
SSc FB is senescent and may indicate that the senescence of SSc FB is independent of its abnormal features.
To analyze the effects of sorbitol accumulation on the survival and growth of epithelial cells from rabbit renal inner medulla, cloning efficiency (an index of cell viability) was measured at normal ...and high glucose and NaCl concentrations and when sorbitol accumulation was prevented by Tolrestat and Sorbinil, which inhibit aldose reductase. With PAP-HT25 cells grown to near confluence, high NaCl increases aldose reductase activity, causing enough rise in cell sorbitol concentration to balance most of the increased osmolality of the high extracellular NaCl. Inhibition of aldose reductase prevents both the increased enzyme activity and sorbitol accumulation in a dose-related manner. Paralleling this, colony-forming efficiency is not affected by the inhibitors at a normal NaCl concentration but is greatly reduced when extracellular NaCl is high. On the other hand, high glucose levels, as occur in diabetes, increase sorbitol content well above the concentration required for osmotic balance and inhibit colony-forming efficiency. Under those conditions, aldose reductase inhibitors lower cell sorbitol and reverse (at 300-350 mosmol/kgH2O) or reduce (at 500-550 mosmol/kgH2O) the decrease in colony-forming efficiency caused by high glucose. Thus sorbitol accumulation is necessary for osmoregulation when induced by high osmolality but is harmful when induced by high glucose.
The effect of pretreatment with aldehydes on the subsequent colony forming efficiency (CFE) of Saccharomyces cerevisiae was investigated. All 21 aldehydes tested inhibited CFE in a dose-dependent ...manner. The effective doses, however, differed markedly from 300 mM to 0.07 mM depending on the functional groups and chain length of the aldehydes. Amongst the nine representatives of n-alkanals, formaldehyde was the most potent inhibitor, reducing CFE to 50 per cent at a dose of 0.3 mM (IC50). In the series of 2-trans-alkenals, acrolein was most effective with an IC50 of 0.08 mM and amongst the 4-hydroxy 2-trans-alkenals, 4-hydroxynonenal was most effective with IC50 of 0.07 mM. In general, effectiveness decreased in the order: 4-hydroxyalkenals > 2-alkenals >> n-alkenals. It is proposed that S. cerevisiae is a promising target cell to elucidate further the molecular mechanisms by which aldehydes, particularly the lipid peroxidation product 4-hydroxynonenal, inhibits cell proliferation.
Optimum forming conditions of electromagnetic tube bulging using direct electrode contact methods are analytically and experimentally investigated. In this paper, the effects of changing the forming ...conditions such as the length of electrode, the capacitance of capacitor bank and charged energy are simulated by FEM for deformation and forming efficiency, and these results are in good agreement with the experimental ones. The forming mechanism is clarified. As the capacitance of capacitor bank and the length of electrode increase, the amplitude of current waves decrease and the period of current increase. The bulge height is reduced when the electrode length increase, but the forming efficiency increase with the electrode length increasing. The larger the capacitance of capacitor bank, the longer the electrode length, the higher the forming efficiency.
![B[a]P-DNA adduct formation ...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/0893-6692/small "B[a]P-DNA adduct formation and induction of human epithelial lung cell transformation")
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