Acta Med Okayama
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Epigenetics is an essential mechanism to control gene expression and fundamental cellular processes. DNA methylation in CpG-rich promoters correlates with gene silencing. Histone modification including histone acetylation and deacetylation determines the stability of the chromatin structure. ⋯ Histone acetylation is a dynamic process regulated by the antagonistic actions of 2 families of enzymes - the histone acetyltransferases (HATs) and the histone deacetylases (HDACs). The balance between histone acetylation and deacetylation serves as a key epigenetic mechanism for transcription factor-dependent gene expression and the developmental process. We review emerging evidence that DNA methylation, histone acetylation modified by HAT and/or HDAC, and transcription factor-associated molecules contribute to a mechanism that can alter chromatin structure, gene expression, and cellular differentiation during chondrogenesis.
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We examined whether the preoperative time required for the Timed "Up and Go" (TUG) test could predict the risk for deep venous thrombosis (DVT) in patients with hip osteoarthritis after total hip arthroplasty (THA). Eighteen patients with DVT diagnosed by venography were selected, and 18 without DVT of the same age and sex and with the same operated side as the DVT group were selected as a control group. We evaluated the 5 preoperative factors that might affect the occurrence of DVT complications, as follows:disease duration, body mass index, serum total cholesterol, subjective pain evaluated by the visual analog scale, and TUG. ⋯ The ROC curve revealed that the cut-off point of 15.3 sec in preoperative time for TUG was sensitive (83.3%) and specific (61.1%) for DVT after THA (odds ratio7.0;95% confidence interval, 1.6-30.8). These results suggested that low preoperative ambulatory ability in patients with hip osteoarthritis might be associated with DVT after THA. An improvement in TUG before surgery might contribute to a decrease in the occurrence of DVT after THA.