The diffusion of gibberellins into agar and water during early germination of Pharbitis nil Choisy

Agar diffusion of imbibed seeds yielded significant amounts of diffusible Gibberellin-like substances. An analysis of the extractable and diffusible gibberellin-like substance, including an analysis of the remaining imbibition water of the seeds, indicated that a significant part of these gibberellin-like substances could be attributed to a net biosynthesis of these substances in the imbibing seeds. At the same time it was found that water diffusion yielded considerably more gibberellin-like activities than comparable agar diffusions i.e. 10 to 12 fold in general.Agar as well as water diffusion showed a temperature effect with regard to the yield of gibberellin-like substances particularly during the first 6 h of diffusion. The yield of these substances is lower at 10°C, and remains lower as shown with consecutive diffusions, in comparison with the yields at 20°C or 30°C.With both agar and water diffusion the sum of activities obtained with consecutive diffusions is always higher, often considerably higher, than equal periods of continuous diffusion which is probably due to inactivation and/or interference of inhibitory substances with the bioassay responses. Finally, water diffusates of both seeds and seedlings of the normal growing cv. Violet of Japanese morning glory contained considerably more gibberellin-like activities than those of the dwarf cv. Kidachi which indicated that normals synthesize more gibberellins than dwarfs.     

Goiter in Tibetan Medicine

The visit of two Tibetan physicians provided a unique opportunity to gain insight into a practice of medicine very different from that of Western civilization. Initial discussions indicated that the practice of medicine and mysticism were inextricably interwoven in the Tibetan culture. Accordingly, the focus of the study was directed to goiter, which is both common in the Himalayas and easy to define.In Tibetan medical practice, illness is considered to be derived from both proximate and distant causes. Three humors, “wind,” “bile,” and “phlegm” are thought to be responsible for normal mental and physical functions when in balance, but disease when out of balance. Goiter was thought to be due to an imbalance of these humors. The Western discovery that endemic goiter in the Himalayas was due to iodine deficiency explained the proximate cause but did not explain why some individuals have goiter and others do not in the same iodine deficient village.     

Heterogeneity of urinary oligosaccharides from mannosidosis: Mass spectrometric analysis of permethylated Man9, Man8, and Man7 derivatives

Three oligosaccharides isolated from the urine of a patient suffering from mannosidosis, a Man₉GlcNAc, a Man₈GlcNAc, and a Man₇GlcNAc, were analyzed by electron impact mass spectrometry at 20 eV after reduction with NaB²H₄ and permethylation. Molecular ions were observed at $\text{m}\text{e}$ 2144, 1940, and 1736, respectively. In the high-mass range very intense ions were found at M-45. The mass spectrum of the homogenous decasaccharide Man₉GlcNAc_1D contains ions that could be attributed to specific parts of each of the three antennae of the molecule. Thus characteristic key ions were recognized. With the aid of these key ions the spectra of the nona- and octasaccharide mixtures could be evaluated in a qualitative and a semiquantitative way. In the nonasaccharide all three possible isomers that can be produced by cleavage of one of the three terminal α-mannoses are present, although in differing amounts. However, only five of the six possible isomers of the octasaccharide could be detected.     

Chronic and acute effects of thyrotropin on phosphatidylinositol turnover in cultured porcine thyroid cells

The 32P incorporation into phospholipids of isolated porcine thyroid cells, cultured for 1-4 days, has been studied in subsequent 2-h incubations. Along with culture ageing, decreased 32P incorporation into total phospholipid of control cells was observed. The presence of 40 munits/ml TSH during the 2 h incubation yielded a relative increase in labelling of phosphatidylinositol, named 'acute phospholipid effect'. A chronic treatment of the cells with TSH concentration ranging from 0.1 to 10 munits/ml ensured the maintenance of a high turnover rate of total phospholipids. The analysis of individual phospholipids revealed that 1-day culture cells in the presence of 0.1 munits/ml TSH presented a strong increase of phosphatidylinositol labelling. This 'chronic phospholipid effect' of TSH can be reproduced by a chronic treatment with dibutyryl cyclic AMP (10(-3)M) or prostaglandin E2 (10(-6)M), which did not evoke a classical phospholipid effect in a 2 h incubation. If TSH (40 munits/ml) is added to the cells in a 2 h incubation, control cells show the classical phospholipid effect whereas cells chronically treated with TSH, dibutyryl cyclic AMP or prostaglandin E2 presented a 'reverse phospholipid effect' i.e. a relative decrease in phosphatidylinositol labelling. 10(-4)M cycloheximide presence during the last 12 h of culture prevented the establishment of the 'chronic phospholipid effect' and of its consequence, 'the reverse phospholipid effect'. On the basis of these results a scheme is proposed in keeping with current hypotheses concerning phosphatidylinositol metabolism.     

Evidence that the hypothermic response of mice to delta-9-tetrahydrocannabinol is not mediated by changes in thermogenesis in brown adipose tissue.

Delta 9-Tetrahydrocannabinol (20 mg/kg i.p.) and propranolol (20 and 50 mg/kg i.p.) produced marked falls in the rectal temperatures of mice kept at an ambient temperature of 22 degrees C. Propranolol (50 mg/kg i.p.) also decreased the thermogenic activity of brown fat, as measured by a decrease in the level of [3H]GDP binding to mitochondria obtained from mouse interscapular brown adipose tissue. In contrast, delta 9-tetrahydrocannabinol (20 mg/kg i.p.) did not affect mitochondrial GDP binding even though the dose used was one shown previously to depress heat production. GDP binding was also unaffected by this cannabinoid in brown adipose tissue taken from mice that had been kept at 13 degrees C instead of 22 degrees C. In mice kept at 34 degrees C, isoprenaline (0.25 and 1.0 mg/kg s.c.) induced a marked rise in rectal temperature and increased the level of GDP binding to brown fat mitochondria. Propranolol (50 mg/kg i.p.) prevented the hyperthermic response to isoprenaline, the mice becoming hypothermic instead. Delta 9-Tetrahydrocannabinol (20 mg/kg i.p.) had no effect on isoprenaline-induced hyperthermia. We conclude from these data that there is no significant involvement of brown adipose tissue in the hypothermic response of mice to delta 9-tetrahydrocannabinol.