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Among the events that control cellular differentiation, the acetylation of histones plays a critical role in the regulation of transcription and the modification of chromatin. Jun dimerization protein 2 (JDP2), a member of the AP-1 family, is an inhibitor of such acetylation and contributes to the maintenance of chromatin structure. In an examination of Jdp2 ‘knock-out’ (KO) mice, we observed elevated numbers of white adipocytes and significant accumulation of lipid in the adipose tissue in sections of scapulae. In addition, mouse embryo fibroblasts (MEFs) from Jdp2 KO mice were more susceptible to adipocyte differentiation in response to hormonal induction and members of the CCAAT/enhancer-binding proteins (C/EBP) gene family were expressed at levels higher than MEFs from wild-type mice. Furthermore, JDP2 inhibited both the acetylation of histone H3 in the promoter of the gene for C/EBPδ and transcription from this promoter. Our data indicate that JDP2 plays a key role as a repressor of adipocyte differentiation by regulating the expression of the gene for C/EBPδ via inhibition of histone acetylation.Cell Death and Differentiation (2007) 14, 1398–1405; doi:10.1038/sj.cdd.4402129; published online 20 April 2007 [ABSTRACT FROM AUTHOR]

The behavior of Zn and other trace elements in mice fed with Zn-deficient diet during the growing period (Zn-dcf. mice) was investigated. A correlation between Zn concentration and Co concentration was found in the liver of Zn-def. mice. Two types of correlation between Zn and Mn concentrations were also recognised for the same livers. These facts suggest that Zn and Co, and also Mn are antagonistic, and that Co- and Mn-substitution for Zn-proteins and other Zn-bound compounds may occur, and/or the substituted compounds may be synthesized in the liver of Zn-def. mice. [ABSTRACT FROM AUTHOR]

Eleven elements in ten organs and tissues of mice fed with Zn-deficient diet (Zn-def. mice) and those fed with control diet (control mice) were determined by INAA. Zinc concentrations in the organs of Zn-def. mice were not distinctly lower than those of control mice except for bone and pancreas, as similar to the predecessors' reported results. However, the Co content increased significantly in all the organs and tissues of Zn-def. mice compared with control mice. The organs and tissues observed were histologicaly normal and no typical symptoms of Zn deficiency disease were recognised. The results suggest that the change of Co-concentration may be regarded as a mark of the prestage for a Zn deficiency disease. [ABSTRACT FROM AUTHOR]

Three cases with small traumatic haematomas in the midline structures of the brain are reported. The neurological examinations of these three patients showed decreased mental activity, and motor disturbances. In spite of their small size, the functional prognosis of these haematomas is very poor. The mechanisms of bleeding and the relevant literature are discussed. [ABSTRACT FROM AUTHOR]

In vitro mRNA synthesis by Sendai virus is almost entirely dependent on the addition of cellular proteins (positive host factors), one of which could be tubulin. In this study, we investigated the distribution of host factors in various rat organs. Extracts from the brain, thymus, heart, lung, testis, ovary, and uterus all supported in vitro Sendai virus transcription, among which the highest activity was obtained with the brain extract. On the other hand, little or no activity was detected in the liver, spleen, and kidney extracts. An inverse correlation between the apparent host factor activity to stimulate mRNA synthesis and RNase activity that hydrolyzes Sendai virus mRNAs was found, except in the liver extract. However, when a transcription initiation complex was isolated and subjected to RNA chain elongation reaction, all of the extracts including those from liver, spleen and kidney, were active. Immunoblotting showed that tubulin molecules were integrated in these initiation complexes, supporting the notion that tubulin is involved in the initiation complex formation. We also identified a transcription inhibitory activity without any detectable RNase activity in the liver extract. This negative host factor seemed to act on RNA chain elongation. It is likely that Sendai virus transcription is regulated by both positive and negative regulatory factors. [ABSTRACT FROM AUTHOR]

Six elements in several organs of mice fed with Zn deficient diet (Zn-def. mice) and those fed with control diet (control mice) were analyzed by INAA. Zinc concentrations in the organs of Zn-def. mice were not distinctly lower than those of control mice except for bone and pancreas. However, Ce content increased significantly in all organs of Zn-def. mice compared with control mice, indicating the partial substitution of Co with Zn in metal proteins or other materials for the Zn-def. mice. [ABSTRACT FROM AUTHOR]