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Traditional Chinese herbal medicines (Kampo) are used to improve flow characteristics of blood (Oketsu). We assumed that by preventing stagnation of blood, these medicines may be beneficial not only in venous but in arterial thrombotic conditions. The present study aimed to assess the antithrombotic effect of three Kampo, using well-established in vitro and animal models of thrombosis. Western-style highfat diet containing 1% Kampo (Shimotsuto, Juzentaihoto or Unseiin) was administered to C57BL/6 mice for 12 weeks. The effect on thrombus formation by laser irradiation of the carotid artery of mice was assessed. In addition the ex-vivo technique of shear-induced platelet reactivity measurement (haemostatometry) and the in vivo test of endothelial function (flowmediated vasodilation) were also used to assess the mechanism of antithrombotic effect. All three medicines have significantly inhibited arterial thrombus formation in mice. According to our studies, the mechanism of antithrombotic effect is based on the inhibition of shear-induced platelet reac- tivity and stimulation of endothelial function (Unseiin). It is assumed that the common ingredients Japanese Angelica Root, Cnidium Rhizome, Peony Root and Rehmannia Root could be responsible for the observed antithrombotic effect.

Homozygous jumonji (jmj(-)/jmj(-)) mice were previously shown to exhibit hepatic hypoplasia and defective hematopoiesis in the liver and die at around embryonic day 15.5 (E15.5), suggesting that jmj is essential for liver development. In order to gain insight into the mechanism of liver development, we analyzed the expression and function of jmj in fetal hepatocytes. The number of hepatocytes in jmj(-)/jmj(-) mice was markedly reduced in comparison with control mice and the expression of jmj in hepatocytes increased along with development. As jmj(-)/jmj(-) embryos die by E15.5, we employed an in vitro culture system in which fetal hepatocytes differentiate in response to oncostatin M. The proliferation potential of jmj(-)/jmj(-) hepatocytes was comparable to that of wild type cells in vitro, however maturation of hepatocytes as evidenced by the expression of liver enzymes such as tyrosine amino transferase was severely impaired by the jmj gene inactivation. These results suggested that jmj plays a pivotal role in the development of mid-fetal hepatocytes to the neonatal stage.

Embryonic stem (ES) cells effectively differentiated into primitive erythroid/mesodermal cells when grown in the absence of both a feeder layer and leukemia inhibitory factor (LIF). The formation of a three-dimensional structure, exogenous mesoderm induction factors and exogenous hematopoietic growth factors were not essential for their differentiation. Primitive erythroid cells were first detected on day 5 in the differentiation-permissive cultures. Differentiation into other mesodermal cells was always preceded by that into primitive erythroid cells. Precursor cells of erythroid cells but of other hematoid cells were also detected in this system. This model system is useful for studying the early steps of mesoderm formation in mouse embryogenesis.

A murine erythroleukemic cell line (1-2-3) which expresses only the temperature-sensitive mutant p53 gene (Ala-to-Val substitution at codon 135) was established. When these cells were cultured at 32 degrees C, the growth rate was reduced significantly and DNA fragmentation, a typical character of apoptosis, was observed. In this process, p53 migrated from cytoplasm to nucleus and protein complexes binding to the p53-responsive element were detected in nuclear extracts of the cells cultured at 32 degrees C by gel-shift assay and transactivation from the p53-responsive element was detected. The expression of the p21 (waf1/cip1/sdi1), cyclin G and gadd45 genes was increased (about 3- to 4-fold that at 37 degrees C), when the cells were cultured at 32 degrees C. However, no significant change was detected in expression of the mdm2, bax and fas genes. No change in the amount of Fas antigen was observed by flow cytometric analysis. Transcripts of the bcl-2 and fas1 gene were not detected in the cells either at 37 degrees C or 32 degrees C. These results suggest that other gene(s) than bax, fas, fas1 and bcl-2 may be important for induction of apoptosis of this erythroleukemic cell line by p53.

A multipotent immature myeloid cell population was produced from a basic fibroblast growth factor (bFGF)-dependent hematopoietic stem cell line, A-6, when cultured with stem cell factor (SCF) replacing bFGF. Those cells were positive for stem cell markers, c-kit and CD34, and a myeloid cell marker, F4/80. Some cell fractions were also positive for Mac-1, a macrophage marker or Gr-1, a granulocytic maker, but negative for an erythroid marker TER119. They also showed the expression of mRNA for the myeloid-specific PU.1 but did not that for the erythroid-specific GATA-1. Among various cytokines, interleukin-3 (IL-3) induced erythroid precursor cells that expressed the erythroid-specific GATA-1 and beta-major globin. The quantitative analysis showed that erythroid precursor cells were newly produced from the immature myeloid cells by cultivation with IL-3. SCF and IL-3 induced stepwise generation of erythroid precursor cells from an A-6 hematopoietic stem cell line.

Electric field effects on behaviors of albino rats, Mongolian gerbils (sand rats), hair-footed Djungarian hamsters, guinea pigs and red sparrows (Avadavat) have been investigated in order to determine whether seismic anomalous animal behaviors (SAABs) witnessed prior to a major earthquake are due to seismic electric signals (SES). Animals placed on a wet conductive floor initially showed grooming, nervous and field avoidance behaviors and finally ran and jumped in panic as the ground field intensity was increased from 1 to 1000 V/m. An electromagnetic model of a fault, in which piezo-compensating bound charges appear as a result of sudden reduction of the piezoelectric polarization due to the release of seismic stress, gives sufficient field intensity to produce a critical body current of a few µA. It is considered that animals showed electrophysiological responses to seismic current.