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Complete Medium (complete + medium)
Selected AbstractsEffect of Silicate-Substitution on Attachment and Early Development of Human Osteoblast-Like Cells Seeded on Microporous Hydroxyapatite Discs,ADVANCED ENGINEERING MATERIALS, Issue 1-2 2010Katharina Guth Hydroxyapatite (HA) is a well-established graft material used in bone repair. Silicon-substituted hydroxyapatite (SA; 0.8,wt% Si) has shown greater bone ingrowth and bone coverage than phase pure HA. To assess the effect of microporosity on sensitivity of cell attachment to surface physiochemistry, microporous SA and HA discs, and control Thermanox (TMX) discs were incubated with osteoblast-like cells (5,×,104 HOS-TE85 cells) under differing tissue culture conditions. To investigate early cellular attachment, organization, and differentiation, cells were also stained for integrin,,5,1, actin, and runt-related transcription factor (RUNX-2), respectively, after incubation on HA, SA, and TMX discs for 3 days. No significant differences emerged between HA, SA, and TMX discs in mean numbers of cells attached in serum free medium (SFM) over 90,min incubation. In contrast, significantly more cells were attached to SA than HA after 180,min incubation in complete medium (C-MEM) containing fetal calf serum (p,<,0.05). Cell attachment to SA and HA discs pre-conditioned in SFM supplemented with fibronectin (FN) was lower than discs pre-conditioned in C-MEM, suggesting sensitivity of an active FN conformation to the presence of co-adsorbates. Confocal microscopy demonstrated significantly more co-localization of integrin ,5,1 and actin on SA than HA. Translocalization of RUNX-2 to the nucleus was stronger in cells incubated on SA. Microporosity did not diminish the effect of surface physiochemistry on cell adhesion, and enhanced cell attachment for SA appears to be mediated by differences in the quality of adsorbed protein rather than via direct effects of substrate chemistry. [source] Mis3 with a conserved RNA binding motif is essential for ribosome biogenesis and implicated in the start of cell growth and S phase checkpointGENES TO CELLS, Issue 7 2000Hiroshi Kondoh Background In normal somatic cell cycle, growth and cell cycle are properly coupled. Although CDK (cyclin-dependent kinase) activity is known to be essential for cell cycle control, the mechanism to ensure the coupling has been little understood. Results We here show that fission yeast Mis3, a novel evolutionarily highly conserved protein with the RNA-interacting KH motif, is essential for ribosome RNA processing, and implicated in initiating the cell growth. Growth arrest of mis3-224, a temperature sensitive mutant at the restrictive temperature, coincides with the early G2 block in the complete medium or the G1/S block in the release from nitrogen starvation, reflecting coupling of cell growth and division. Genetic interactions indicated that Mis3 shares functions with cell cycle regulators and RNA processing proteins, and is under the control of Dsk1 kinase and PP1 phosphatase. Mis3 is needed for the formation of 18S ribosome RNA, and may hence direct the level of proteins required for the coupling. One such candidate is Mik1 kinase. mis3-224 is sensitive to hydroxyurea, and the level of Mik1 protein increases during replication checkpoint in a manner dependent upon the presence of Mis3 and Cds1. Conclusions Mis3 is essential for ribosome biogenesis, supports S phase checkpoint, and is needed for the coupling between growth and cell cycle. Whether Mis3 interacts solely with ribosomal precursor RNA remains to be determined. [source] Improvement of Yarrowia lipolytica lipase production by fed-batch fermentationJOURNAL OF BASIC MICROBIOLOGY, Issue 2 2009Patrick Fickers Abstract Two different types of fed-batch fermentation were investigated to improve production yields of the Lip2 extracellular lipase in Y. lipolytica mutant-strain LgX64.81 grown in a 20l bioreactor. Compare to batch cultures, culture feeding with the complete medium led to a 2-fold increased lipase production (2016 ± 76 U ml,1) whereas addition of a combination of glucose and olive oil led to a 3-fold increase. The high level of lipase production obtained on glucose media with Y. lipolytica LgX64.81 could be related to its phenotype i.e. a lower sensibility to glucose catabolite repression due to a modification in the level of HXK1 expression. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Estrogen signaling and disruption of androgen metabolism in acquired androgen-independence during cadmium carcinogenesis in human prostate epithelial cellsTHE PROSTATE, Issue 2 2007Lamia Benbrahim-Tallaa Abstract BACKGROUND Lethal prostate cancers often become androgen-independent due to androgen receptor (AR) overexpression. The role of cadmium in prostate tumor progression was determined. METHODS Control and cadmium-transformed prostate epithelial cells (CTPE) were compared for steroid-induced proliferation, steroid receptor expression, and androgen metabolism. RESULTS CTPE cells showed rapid proliferation in complete medium and sustained proliferation in steroid-reduced medium. Androgens stimulated significantly less cell proliferation and AR-related genes expression in CTPE cells. 5,-Dihydrotestosterone increased PSA expression more effectively in control cells. Flutamide reduced 5,-dihydrotestosterone-stimulated growth less effectively in CTPE cells compared to control. CTPE cells showed decreased p27 expression. Estrogen receptors were overexpressed and estradiol markedly stimulated proliferation in CTPE cells. In CTPE cells 5,-aromatase was markedly increased, while 5,-reductase was decreased. CONCLUSIONS Cadmium-induced malignant transformation stimulates androgen independence, unrelated to AR expression or activity. Increased estrogen receptor and 5,-aromatase expression suggest estrogen signaling may be critical to this process. Prostate © 2006 Wiley-Liss, Inc. [source] | ||||||||||