The structure of a local population and dispersal pattern in the Styan's grasshopper warbler,Locustella pleskei

The breeding sites of Styan's grasshopper warblers are restricted to small islands and distributed discretely. The study on the marked population was conducted on two islets, Okitsu-jima and Ohtsukue-jima, located near Fukuoka, Japan, from 1981 to 1989. About 20 and 70 birds bred on the two islets, respectively, and the mean density of breeding pairs was 25.5 ha⁻¹. The dispersal pattern and population, structure were examined. Adult birds returned to the same breeding site. Males always reoccupied the same territory as in previous years but females not. Males were more philopatric and only female yearlings dispersed over long distances and moved between the breeding sites in Hakata Bay. The returning rate was 0.57 for adults, and 0.21 for juveniles. The age distribution of birds at Ohtsukue-jima was almost stable, while that at Okitsu-jima was unstable because it was a marginal habitat for the birds. Estimating from the dispersal pattern and age structure of this warbler the population near Fukuoka consists of only four islets and is almost stable.     

Elevated serum α-fetoprotein level of nude mice bearing hepatoma cells by treatment with monoclonal antibodies to α-fetoprotein

This study was carried out to clarify the reason for elevation of serum α-fetoprotein (AFP) level of nude mice bearing hepatoma cells after treatment with monoclonal antibodies (MoAbs) to AFP. MoAbs to AFP showed no effect on the cumulative amounts of AFP secreted from human hepatoma cell line, HuH-7, in vitro. However, the treatment of nude mice bearing HuH-7N cells (HuH-7 xenograft) with MoAbs to AFP led to elevation of the serum AFP level in spite of the fact that the growth curve of HuH-7N cells was similar to that for PBS treatment. This apparent elevation of the serum AFP level is thought to be due to the slow elimination of AFP-MoAb immune complexes with little lattice structure from circulation, but not the enhancement of AFP secretion of HuH-7N cells. Thus, when using a MoAb alone or MoAb-drug conjugate, the serum AFP level should only be cautiously used as a tumor marker for evaluating the targeting immunotherapy.     

Phylogeography of the temperate grassland plant Tephroseris kirilowii (Asteraceae) inferred from multiplexed inter-simple sequence repeat genotyping by sequencing (MIG-seq) data

Journal of Plant Research - A group of temperate grassland plant species termed the “Mansen elements” occurs in Japan and is widely distributed in the grasslands of continental East...     

A pathway through interferon-gamma is the main pathway for induction of nitric oxide upon stimulation with bacterial lipopolysaccharide in mouse peritoneal cells.

Production of nitric oxide (NO) in response to bacterial lipopolysaccharide (LPS) was investigated using cultures of mouse peritoneal exudate cells (PEC) and the macrophage cell line RAW264.7. In the presence of anti-(interferon-gamma) (IFN-gamma), NO production was markedly suppressed in the PEC culture but not in the RAW264.7 culture. In the PEC culture, LPS induced both IFN-gamma production and activation of IFN response factor-1, which leads to the gene expression of inducible NO synthase, but neither was induced in the culture of RAW264.7 cells. In addition to anti-(IFN-gamma), antibodies against interleukin (IL)-12 and IL-18 showed a suppressive effect on LPS-induced NO production in the PEC culture, and these antibodies in synergy showed strong suppression. Stimulation of the PEC culture with IL-12 or IL-18 induced production of IFN-gamma and NO, and these cytokines, in combination, exhibited marked synergism. Stimulation of the culture with IFN-gamma induced production of NO, but not IL-12. The macrophage population in the PEC, prepared as adherent cells, responded well to LPS for IL-12 production, but weakly for production of IFN-gamma and NO. The macrophages also responded well to IFN-gamma for NO production. For production of IFN-gamma by stimulation with LPS or IL-12 + IL-18, nonadherent cells were required in the PEC culture. Considering these results overall, the indirect pathway, through the production of intermediates (such as IFN-gamma-inducing cytokines and IFN-gamma) by the cooperation of macrophages with nonadherent cells, was revealed to play the main role in the LPS-induced NO production pathway, as opposed to the direct pathway requiring only a macrophage population.     

Genetic markers distinguishing between the two subspecies of the rosy bitterling,Rhodeus ocellatus (Cyprinidae)

Eleven populations of the rosy bitterling,Rhodeus ocellatus, from different localities in Japan, were genetically compared at 16 protein-coding loci using starch-gel electrophoresis. Two loci,Ldh-2 andPgdh, were demonstrated as diagnostic markers for the identification of two subspecies;R. ocellatus kurumeus, which is native to Japan, andR. ocellatus ocellatus, which was introduced from China. The two subspecies were distinguished by the complete substitution of different alleles between them. Population ofR. ocellatus kurumeus occurring in Yao City, Osaka, and in Kanzaki, Saga Prefecture were genetically closely related to each other (genetic distance: D=0.056) but distantly so toR. ocellatus ocellatus from Saitama Prefecture (D=0.202 or 0.265). Electrophoretic analyses also elucidated the existence of hybrid populations of the two subspecies. The populations ofR. ocellatus kurumeus in Yao City had lower genetic variability and a lower incidence of white coloration on the ventral fins than populations of the same in Saga Prefecture. The present study strongly implies that the introduction of the foreign freshwater fishes with subspecific differentiation, into the original range of indigenous subspecies, should be averted not to bring the genetic pollution.     

Glutamate-Induced Loss of Ca2+/Calmodulin-Dependent Protein Kinase II Activity in Cultured Rat Hippocampal Neurons

Abstract: The exposure of cultured rat hippocampal neurons to 500 µ M glutamate for 20 min induced a 55% decrease in the total Ca²⁺/calmodulin-dependent protein kinase II (CaM kinase II) activity. The Ca²⁺-independent activity and autophosphorylation of CaM kinase II decreased to the same extent as the changes observed in total CaM kinase II activity, and these decreases in activities were prevented by pretreatment with MK-801, an N -methyl- d -aspartate (NMDA)-type receptor antagonist, and the removal of extracellular calcium but not by antagonists against other types of glutamate receptors and protease inhibitors. Similarly, the decrease in the CaM kinase II activity was induced by a Ca²⁺ ionophore, ionomycin. Immunoblot analysis with the anti-CaM kinase II antibody revealed a significant decrease in the amount of the enzyme in the soluble fraction, in contrast with the inverse increase in the insoluble fraction; thus, the translocation was probably induced during treatment of the cells with glutamate. These results suggest that glutamate released during brain ischemia induces a loss of CaM kinase II activity in hippocampal neurons, by stimulation of the NMDA receptor, and that inactivation of the enzyme may possibly be involved in the cascade of the glutamate neurotoxicity following brain ischemia.