Discussions are given to a step-wise discontinuity between Nd and Gd observed in acid extraction or dissolution of REE from silicate rock powder. It is concluded that, aside from polymorphism of REE sesquioxides, the change of hydration number from 9 to 8 in the primary hydration sphere surrounding lanthanide cations is a significant parameter responsible for the observed fact, although attention has been paid only to effect of polymorphism of sesquioxides of REE in the previous communication. There appears to be a parallel relationship between these two parameters.
The circadian rhythm of eclosion in the house fly, Musca domestica, was measured using new apparatus, designed for large populations. The rhythm of eclosion was found to depend upon separate biological clocks in the pupal and larval stages. A comparison of the wild type and triple mutant wbp (white eyes, brown body and pointed wings) showed that the mutant has a short periodicity of eclosion. Cross breeding analysis suggested that a single gene controls the short periodicity of the eclosion rhythm in the triple mutant (wbp).
A pseudo-point group D6h and its subgroups are applied to the symmetry characterization of tri- and tetra-substituted cyclohexane derivatives under flexible and fixed conditions. After the subgroups are classified into chiral and achiral ones as well as into isoenergetic and anisoenergetic ones, the conformational changes of the derivatives are categorized into isoenergetic-achiral (Types I and I'), isoenergetic-chiral (Type II), anisoenergetic-achiral (Type III), and anisoenergetic-chiral cases (Type IV). These cases are rationalized by the subduction from D6h to D3d.
Previous study showed that synovial fibroblasts derived from patients with rheumatoid arthritis (RA) and osteoarthritis (OA) express β-preprotachykinin (PPT)-A mRNA and release substance P (SP). In this study, we examined the presence of an isoform of PPT-A mRNA in synovial and normal skin fibroblasts by reverse transcription-polymerase chain reaction (RT-PCR) analysis. RA synovial fibroblasts, but not OA synovial and skin fibroblasts, expressed α-isoform PPT-A mRNA together with β-PPT-A mRNA. However, expression of γ- and δ-PPT mRNAs was not observed in synovial and skin fibroblasts. Levels of both α- and β-PPT-A mRNAs were increased in RA fibroblasts treated with transforming growth factor (TGF)-β and basic fibroblast growth factor (bFGF). Treatment with TGF-β and bFGF strongly increased the expression of α- and β-PPT-A mRNAs compared to the individual treatment. Peak levels of α-PPT-A mRNA were reached at 8h whereas those of β-PPT-A mRNA were maximal at 12h after treatment with TGF-β and bFGF. These findings suggest that SP production by synovial fibroblasts in RA is regulated through signaling pathways that lead to the generation of both α- and β-PPT-A mRNAs.
Methyl-CpG binding domain column chromatography enables the separation of DNA fragments on the basis of the number of methylated CpG sites within the fragment. However, the exact elution profile of a specific DNA fragment is unpredictable. In order to address this problem, we have investigated the methylation status of genomic DNA fragments having similar elution profiles. We found that genomic DNA fragments that had high affinity to the column included those with high-density methylation, moderate methylation, and monoallelic methylation. Some DNA fragments associated with both bona fide CpG islands, which are methylation-free, and methylated Alu repeated sequence had high affinity to the column. These results suggest that methylation status of DNA fragments having high affinity to the column is heterogeneous and caution is required for the interpretation of the results.