Structural changes of deoxyribonucleoprotein fibres following γ-irradiation under aerobic and hypoxic conditions

Summary The DNP fibres -irradiated under aerobic condition showed a reduction of their diameter, while no remarkable changes were observed in the DNP fibres irradiated under hypoxic condition by scanning electron microscopy.     

Antitumor activity of the Isodon diterpenoids: structural requirements for the activity.

A significant antitumor activity of oridonin (1) and lasiokaurin (2), the kaurene-type diterpenoids of Isodon species, was shown by their i.p. injection to the test mice inoculated by Ehrlich ascites carcinoma. Enmein (8), compounds 9 and 3 were also active under larger dose. Subsequently, the relationship between their chemical structure and antitumor activity was investigated, and the activity of oridonin (1) and lasiokaurin (2) was rationalized in terms of their structural feature.     

3-Hydroxy-3-Methylglutaric acid and triton-induced hyperlipidemia in rats

Summary 3-Hydroxy-3-methylglutaric acid (HMG) significantly decreased cholesterol, triglyceride and phospholipid levels in whole serum, serum -lipoproteins and liver of Triton-induced hyperlipidemic rats. Therapeutically 50 mg HMG/kg is equivalent to 200 mg nicotinic acid/kg in lowering all these lipid parameters. HMG may exert its hypolipidemic effect through inhibition of lipoprotein synthesis.Acknowledgments. We are grateful to Dr.M. Saleemuddin for encouragement, Dr.P. E. Schurr, Upjohn Co. USA for generous gift of Triton W. R 1339 and Lady Tata Memorial Trust (India) for financial assistance to one of us (SYKY).     

3-Hydroxy-3-methylglutaric acid and experimental atherosclerosis in rats

Summary In rats 3-hydroxy-3-methylglutaric acid effectively counteracts the lipemic and atherosclerotic response of massive doses of vitamin D₂. It regressed the formation of atheromatous arterial lesions. Furthermore the significant decrease in serum -lipoprotein levels on HMG treatment could be due to decrease in VLDL triglyceride and cholesterol levels.Acknowledgments. The authors are indebted to Dr.W. Drell, President, Calbiochem, San Diego, California, USA, for generous gift of HMG and Lady Tata Memorial Trust, India, for providing financial assistance to one of us (S.Y.K.Y.).     

Hymenin,a novel α-adrenoceptor blocking agent from the Okinawan marine spongeHymeniacidon sp.

Summary A novel bromine-containing alkaloid, hymenin, has been isolated from the Okinawan marine spongeHymeniacidon sp. as a potent -adrenoceptor blocking agent and its structure determined to be1 on the basis of the spectral data.     

Enzyme-linked immunosorbent assay for measuring serum IgE

Summary Serum IgE was measured by a sandwich method using polystyrene beads coated with anti-IgE -globulin and peroxidase labelled anti-IgE -globulin. The method was simple, and as sensitive as the radioimmunoassay.We are grateful for the skillful assistance of Mrs K. Kobayashi.     

Effects of thyrotrophic-releasing hormone (TRH) on thermoregulation in the rat

Summary At ambient temperatures (T_a) of both 8 and 22°C, intraventricular administration of TRH (10–80 g) produced a dose-dependent hypothermia in rats. The hypothermia was due to both decreased metabolic heat production and cutaneous vasodilatation. In contrast, at 30°C T_a, TRH increased metabolic heat production (due to behavioral excitation) and led to hyperthermia.This work was supported by the grants from the National Science Council of Republic of China and the Pjing-Ling Neurological Foundation (VGH, Taipei, Taiwan).     

Anti-oxidative effect of coenzyme Q10

Summary Coenzyme Q₁₀ is effective as an anti-oxidant like -tocopherol, especially in the heart.