It has been reported that PTH exerts bone-forming effects in vivo when administered intermittently. In the present study, the anabolic effects of PTH(1-34) on osteoblast differentiation were examined in vitro. Osteoblastic cells isolated from newborn rat calvaria were cyclically treated with PTH (

The mechanisms controlling the initiation of mineralization of bone matrix are not clear. To examine this process, we established a cell line called MLO-A5 that mineralizes in sheets, not nodules, within 3 days of culture in the presence of ␤-glycerophosphate (␤-GP) and ascorbic acid and within 7 days in the absence of ␤-GP and ascorbic acid. The mineral formed in both cases was shown to be bonelike apatite by Fourier transformed infrared (FTIR) spectroscopy. Mineral-to-matrix ratios (min/matrix) calculated from the FTIR data, which are related directly to ash weight, were approximately 0.4 in the absence of ␤-GP and ascorbic acid and approximately 1.2 in the presence of ␤-GP and ascorbic acid. By comparison, these ratios in fetal rat calvarial cells without ␤-GP equal 0 and with ␤-GP 1.9. This cell line and three others (MLO-A2, -D1, and -D6) were isolated from the long bones of transgenic mice expressing the large T-antigen driven by the osteocalcin promoter, the same mice from which the osteocyte-like cell line MLO-Y4 was isolated.(

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We present a liquid chromatography–mass spectrometry (LC-MS)-based method for comprehensive quantitative identification of post-transcriptional modifications (PTMs) of RNA. We incorporated an in vitro-transcribed, heavy isotope-labeled reference RNA into a sample RNA solution, digested the mixture with a number of RNases and detected the post-transcriptionally modified oligonucleotides quantitatively based on shifts in retention time and the MS signal in subsequent LC-MS. This allowed the determination and quantitation of all PTMs in Schizosaccharomyces pombe ribosomal (r)RNAs and generated the first complete PTM maps of eukaryotic rRNAs at single-nucleotide resolution. There were 122 modified sites, most of which appear to locate at the interface of ribosomal subunits where translation takes place. We also identified PTMs at specific locations in rRNAs that were altered in response to growth conditions of yeast cells, suggesting that the cells coordinately regulate the modification levels of RNA.

The number of MAIT cells in the peripheral blood and inflamed mucosae of patients with UC and CD was lower than that in non-IBD controls. Also, MAIT cells from patients with IBD exhibited proapoptotic features. These data suggest the pathological involvement and the potential for therapeutic manipulation of these cells in patients with IBD.