Alterations in cellular characteristics associated with transformation were compared among various agents, including simian virus 40, mouse polyoma virus, adenovirus type 12, the E1A region of adenovirus type 12, Rous sarcoma virus, v-H-ras oncogene, and N-methyl-N’-nitro-N-nitrosoguanidine. To avoid the difficulty in interpretation due to differences in the original cellular characteristics, all transformed lines (three to four independent lines for each agent) were derived from the same parental line, i.e. rat clonal diploid fibroblasts 3Y1. Doubling time, saturation density, serum requirement, efficiency of colony formation, Ca dependency, anchorage dependency, cell volume, density-dependent inhibition of proliferation, and alteration of morphology were examined. In the lines transformed either by DNA virus, RNA virus, or transforming oncogene, the characteristics were similar among the lines induced by the same transforming agent but distinguishable between the lines induced by different agents. In such cases, a transformed line displayed phenotypes specific to each transforming agent. In contrast, nitrosoguanidine-transformed lines showed different properties. Only one characteristic was shared by all the transformed lines: the ability to attain a higher saturation density than that of the untransformed parent. The fact that (cellular) densitydependent inhibition of DNA synthesis became weak may be responsible for this characteristic.

A 45 K M, G-actin-binding protein was isolated from bovine aorta. This protein had an amino acid composition very similar to that of 84 K M, gelsolin and cross-reacted with anti-gelsolin antibodies. The 45 K M, protein consisted of two isoforms, I and II, as revealed by isoelectric focusing. Isoform I was slightly more acidic than isoform II and more abundant. Isoform II was not distinguishable from a chymotrypic peptide, CT47, of gelsolin in chain weight and isoelectric point values. The 45 K M, protein is shown to bind to G-actin by chemical cross-linking. It considerably lowered the initial rate of actin polymerization, but the inhibition became much less marked at a steady state, suggesting that the binding of this protein to actin was not so tight as CT47. Both isoforms of the 45 K M, protein were detected in a guanidine-HCl extract of freshly obtained bovine aorta. It is suggested that the 45 K M, protein derived from 84 K M, gelsolin exists in viva.

High titer of autoantibody against glial fibrillary acidic protein (GFAP) was found in the serum from patients with Alzheimer’s disease. This was shown by 1) positive immunostaining of GFAP by Western blotting, 2) histochemical immunostaining of astrocytes of human brain, and 3) determination of autoantibody levels by enzyme-linked immunosorbent assay with GFAP as antigen. High anti-GFAP IgG level (quantity of IgG higher than that of 500 ng/ml monoclonal mouse IgG against GFAP) was found in 80% of Alzheimer patients (20/25), but only in 9.1% (3/33) of multi-infarct dementia patients and in 3% (4/126) of the control subjects. Determination of the autoantibody level against GFAP can be useful for diagnosing Alzheimer’s disease in the elderly population with dementia.

1) Amphotericin B (AMB) was found to suppress the chemotactic function of macrophage-like cell lines, CANS and HINS, in a dose-dependent manner. Marked suppression was observed 1 h after the AMB treatment. Nystatin and filipin also showed similar but weaker effect. 2) Spontaneous cytotoxicity to EL4 target by macrophage cell lines 2-6 h after the treatment with AMB differed among the cell lines; AMB enhanced the activity in CANS-31a, had no effect in CANS-83, and suppressed the activity in CANS-196 and HINS-B3 cells. However, the cytotoxic activity of all the macrophage cell lines was suppressed 12 h after the treatment. Less marked but similar effects were observed with nystatin and filipin. 3) Incubation with mouse interferon γ (IFN_γ) followed by lipopolysaccharide (LPS) markedly enhanced the expression of both H-2^ｄ and I-A^d antigens in CANS-31a and CANS-196 cell lines. AMB also induced a significant enhancement of H-2^d and I-A^d antigen expression. 4) Incubation with IFN_γ followed by LPS enhanced transcription of H-2 and β2-microglobulin (β2-m) genes in CANS-31a cells as the time of IFN_γ-treatment was lengthened. AMB also showed a less marked but similar effect in the same cell line. 5) AMB induced enhanced and prolonged transcription of c-fos and macrophage-specific MS2 and MS7 genes in CANS-31a cells. 6) The results suggest that AMB enhances the expression of various genes after forming complexes with sterols in the cell membrane ofmacrophage cell lines while inhibiting receptor-ligand interaction, leading to enhancement or suppression of the macrophage function.

A monoclonal antibody raised against a crude myosin preparation from human soleus muscle was shown to react with rabbit skeletal muscle connectin, and also with the NF-H (200 K) and NF-M (160 K) subunits of neurofilament of the rabbit. In human neurofilament proteins, the antibody reacted with NF-H but not with NE-M. Immunofluorescence studies using the antibody revealed that it stained not only human skeletal and cardiac muscles but also nerve axon and central nerve cell body. Thus, the present work demonstrates an immunological homology between connectin, an elastic filamentous protein in striated muscles, and two subunits (NF-H and NF-M) of neurofilament, an intermediate filament in the nerve cells.

Prepubertal male Mongolian gerbils (Meriones unguiculatus) were exposed to short photoperiods (10L : 14D) for up to 15 weeks to determine the photoperiodic involvement in the onset of reproductive activity. Gerbils were killed at the beginning of the experiment and after 3, 4, 7, 8, 11 or 15 weeks of photoperiodic exposure. Short photoperiod-exposed gerbils were compared to age-matched long photoperiod-exposed (14L : 10D) animals. Serum testosterone levels were depressed after 3, 4 and 8 weeks of short photoperiod exposure but were not different from long photoperiod exposed gerbils after 7, 11 or 15 weeks of photoperiod exposure. Testes weights increased throughout the pubertal period with a slight depression observed after 4 weeks of short photoperiod exposure. These data indicate that short photoperiod exposure alters the testosterone surge which occurs during pubertal development in the gerbil without major modifications in testicular development. It appears that short photoperiod exposure depresses or modifies the rhythm of pubertal testosterone production in male gerbils.

Streptozotocin-induced experimental diabetes significantly lowered both basal and ACTH-stimulated corticosterone production in rats, whose hypothalamo-hypophyseal-adrenal axis had been pharmacologically interrupted. Basal and ACTH-stimulated activity of two key enzymes of steroid synthesis (⊿⁵-3β-hydroxysteroid dehydrogenase and 11β-hydroxylase) were also notably reduced in the zona fasciculata of diabetic rats. Insulin infusion completely reversed all these streptozotocininduced effects. The conclusion is drawn that the chronic lowering in the level of circulating insulin impairs the steroidogenic capacity of rat zona fasciculata.

When intramuscular pH was raised from 7.0 to 7.2, the contractile system became more sensitive to Ca, resulting in a larger tension. The process of Ca-induced Ca release in the sarcoplasmic reticulum was also facilitated. With a slight increase in the intracellular pH, sustained muscle contracture could easily be introduced.