Identification of novel non-peptide CXCR4 antagonists by ligand-based design approach

The design and synthesis of novel non-peptide CXCR4 antagonists is described. The peptide backbone of highly potent cyclic peptide-based CXCR4 antagonists was entirely replaced by an indole framework, which was expected to reproduce the disposition of the key pharmacophores consistent with those of potential bioactive conformations of the original peptides. A structure–activity relationship study on a series of modified indoles identified novel small-molecule antagonists having three pharmacophore functional groups through the appropriate linkers.     

Development of high-throughput screening system for osteogenic drugs using a cell-based sensor

To effectively treat osteoporosis and other bone-loss disorders, small compounds that potently induce bone formation are needed. The present study initially attempted to establish a monitoring system that could detect osteogenic differentiation easily, precisely, and noninvasively. For this purpose, we established pre-osteoblastic MC3T3E1 cells stably transfected with the GFP reporter gene driven by a 2.3 kb fragment of rat type I collagen promoter (Col1a1GFP-MC3T3E1). Among these cells, we selected a clone that fluoresced upon osteogenic stimulation by BMP2. The GFP fluorescence intensity corresponded well to the intensity of alkaline phosphatase (ALP) staining and to the level of osteocalcin (Oc) mRNA. Using this system, we screened natural and synthetic compound libraries and thus identified an isoflavone derivative, glabrisoflavone (GI). GI induced ALP staining and Oc mRNA in a dose-dependent manner. The Col1a1GFP-MC3T3E1 system may be useful for identifying novel osteogenic drugs.     

Postnatal changes in sublobular distribution of NADPH-cytochrome P-450 reductase in rat liver

Summary Immunohistochemical distribution of NADPH-cytochrome P-450 reductase (NADPH-ferrihaemoprotein reductase; EC 1.6.2.4.) in the liver lobule was examined during development of the rat. From the 19th day of gestation to 4 days after birth, the enzyme was distributed uniformly throughout the lobule. The immunostaining for the enzyme was weak before birth, and became slightly stronger after birth. A slightly uneven distribution of immunoreactivity, stronger in perivenular zones, appeared at 5 days after birth. Then, the staining intensity in perivenular zones became progressively stronger with age, except for a slight increase between 10 and 20 days of age. The intensity in periportal zones also increased gradually, although it remained weaker than that in perivenular zones. Around 30 days of age, the distribution of the immunostaining, stronger in perivenular than in periportal zones, was similar to that seen in the lobules of adult animals. thus, heterogeneity among hepatocytes with respect to the enzyme content is not present in fetal and newborn rats but develops gradually during postnatal development; the postnatal growth of the liver is accompanied by a change in the pattern of the distribution of this enzyme within the lobule.     

Immunohistochemical localization of type II and type I collagens in articular cartilage of the femoral head of dexamethasone-treated rats

The immunohistochemical localization of type II and type I collagens was examined in the articular cartilage of the femoral head of growing rats injected systemically with 5 mg kg−1 dexamethasone for 2 weeks every other day. The intensities of immunostaining for type II collagen, measured by microphotometry, was highest in the flattened cell layer and high in the hypertrophic cell layer, moderate in the proliferative cell and transitional cell layers and low in the superficial layer. After dexamethasone administration, the intensities decreased markedly in the flattened cell layer and slightly in the hypertrophic cell layer, although the decreases in other layers were negligible. The staining intensities for type I collagen were highest in the flattened cell layer, low in the superficial and transitional cell layers and very low in the proliferative and hypertrophic cell layers. After dexamethasone administration, the intensities increased markedly in the flattened cell layer and slightly in the superficial and proliferative cell layers, but did not change in the transitional and hypertrophic cell layers. Thus, dexamethasone administration caused a decrease in type II collagen and an increase in type I collagen in the matrix of the surface portion of articular cartilage. The composition of isoforms of collagen in the matrix changed after the steroid administration. The results strongly suggest that the shift in collagen composition from type II to type I predominance is a cause of the degeneration of the articular cartilage after glucocorticoid administration. This revised version was published online in November 2006 with corrections to the Cover Date.     

Rapid extraction of high-quality genomic DNA from Porphyra yezoensis (Bangiales, Rhodophyta)

We developed a simple, rapid and stable method for extraction of high molecular weight DNA from the marine red alga Porphyra yezoensis Ueda using both guanidium treatment and QIAGEN? kit (Funakoshi, Tokyo, Japan). The method does not require expensive equipment and complex steps. The DNA yield averaged 1.5 μg 100 mg^?1 of Porphyra tissue and the A260/A280 and A230/A260 ratios of the DNA were approximately 1.8 and 0.4, respectively. It was of sufficient quality to be used for not only polymerase chain reactions but also other DNA manipulation techniques such as restriction digestion and construction of genomic libraries.     

Resurrection of Rabdophaga salicivora Shinji (Diptera: Cecidomyiidae), a Japanese gall midge formerly misidentified as a North American species, Rabdophaga rigidae (Osten Sacken), with observations on the phylogenetic relationships of its populations in Japan and the Russian Far East

Intercontinental biotic connections between Eurasia and North America are common in many gall midge genera (Diptera: Cecidomyiidae), but only a few species have been recorded from both continents. In Japan, four gall midge species had been previously considered to be identical to North American species, but three of these cases have already been disproved. We examined the remaining species, Rabdophaga rigidae, which had been originally described from Japan as Rabdophaga salicivora in 1938, later recorded from the Russian Far East in 1967, and synonymized with a North American species, R. rigidae, in 1982. Morphological features and partial sequence data of the mtDNA cytochrome oxidase subunit I (COI) region suggested that the Japanese species is a distinct species and is identical to the species recorded from the Russian Far East. We therefore apply the original name, R. salicivora, to the Japanese and the Russian species. In addition, on the basis of a molecular phylogenetic analysis, we conclude that R. salicivora possibly came to the Japanese Archipelago through the Korean Peninsula and established itself first in the southern parts of Japan. Then, it expanded its distribution range to northern parts of Honshu, but could not reach Hokkaido, probably because of the Tsugaru Strait between Honshu and Hokkaido.