Taq I-generated HLA-DQ αpolymorphism in Japanese patients with narcolepsy

Taq I-generated HLA-DQrestriction fragment length polymorphism was examined in Japanese patients with narcolepsy. All patients were DR2 positive and shared a 6.0 kb fragment, although this fragment was found only in 54 % of the healthy DR2-positive Japanese. This finding added the DQ gene to the list of candidates for the possible narcolepsy-susceptibility gene. In contrast, there was no complete association between narcolepsy and DXrestriction fragment length polymorphism. These findings suggest that a narcolepsy-susceptibility gene is located closer to the DQ locus than to the DX locus.     

Establishment of a Sensitized Immunoblotting Method for Measuring Plant Tubulin Content

A sensitized immunoblotting method was established for measuringsmall amounts of plant tubulin. The method involves electrophoretictransfer of protein including tubulin from SDS-polyacrylamidegels onto nitrocellulose paper, successive incubation of thenitrocellulose paper with a mouse monoclonal antibody to - orß-tubulin of chicken brain, an antibody to mouse IgGas the second antibody and the radioactive iodinated proteinA, and determination of the radioactivities of the bands onthe nitrocellulose paper thus probed. The radioactivities werelinearly proportional to the amounts of - or ß-tubulinfrom dark-grown Vigna mungo seedlings within a range of 4 to56 ng or of 4 to 32 ng, respectively. This method was used to estimate the tubulin contents of severalplant species using Vigna tubulin as a standard. -Tubulin contentsthus estimated were 25, 9, 19 and 11 µg-equivalents ofVigna tubulin per mg protein for Vigna seedlings, Daucus suspensioncells, Catharanthus suspension cells and Mougeolia cells, respectively.ß-Tubulin contents of Vigna, Daucus, Catharanthusand Mougeotia cells were 29, 10, 13 and 5 µg-equivalentsof Vigna tubulin per mg protein, respectively. (Received August 6, 1985; Accepted December 5, 1985)     

Effects of Nutrient Limitation and {gamma}-Irradiation on Tracheary Element Differentiation and Cell Division in Single Mesophyll Cells of Zinnia elegans

The effects of nutrient limitation and -irradiation on trachearyelement differentiation and cell division were investigatedusing single cells isolated from the mesophyll of Zinnia elegans.When the phosphate concentration of the medium was reduced to10 µM (1/50 of Fukuda and Komamine's medium, 1980a), thefrequency of cell division during 4 days of culture decreased,while the frequency of tracheary element differentiation wasunaffected. -Irradiation with a dose of 92 Gy at 36 h of culturepreferentially and thoroughly suppressed cell division withoutreducing the number of tracheary elements formed. The appearanceof secondary cell wall thickenings was delayed by irradiation,but synchrony was maintained. Thus the Zinnia system previouslyreported [Fukuda and Komamine (1980a) Plant Physiol. 65: 57]was improved to give a more useful system for the study of cytodifferentiation,in which tracheary element formation occurred from single cellswithout cell division. ¹Present address: Biological Institute, Faculty of Science,Tohoku University, Sendai, Miyagi 980, Japan. (Received November 28, 1985; Accepted February 22, 1986)     

Long term treatment of congenital hypothyroidism with L-triiodothyronine: 24 year follow-up

A congenital hypothyroidism complicated by ventricular septal defects which was treated with L-triiodothyronine (L-T3) alone from 1 5/12 to 25 years, is described. The patient's growth and development was satisfactory and without side effects. It suggests that L-T3 may be a safe drug for long term treatment of congenital hypothyroidism.     

Sleep-related growth hormone release in thyrotoxic patients before and during propylthiouracil therapy

Hyporesponsiveness of GH to insulin-induced hypoglycemia has previously been reported in hyperthyroid patients. In order to clarify the GH secretion in thyrotoxic patients, sleep-related increases in the serum GH concentration were investigated. Eight thyrotoxic females ranging in age from 7 to 15 were treated with PTU. Blood samples for measurement of GH were drawn every 15 minutes during the first few hours of sleep before and during the treatment lasting about three months. The mean maximum serum GH level before the treatment was 10.0 +/- 5.5 ng/ml (mean +/- SD); this rose to 23.2 +/- 14.6 ng/ml (P less than 0.02) during the treatment. The maximum value of more than 10 ng/ml was detected in only 3 out of the 8 patients before treatment. On the other hand, serum GH levels during PTU administration rose to above 10 ng/ml in all patients except one. It was revealed that sleep-related elevations of GH occurred early in sleep and in close association with a slow-wave EEG pattern. The results show that sleep-related GH release is low in the hyperthyroid state, but becomes significantly elevated during PTU administration. However, even in the hyperthyroid state, the sleep-related secretion of GH is closely correlated with the slow-wave sleep stage as in the euthyroid condition.     

Plasma concentration of prolactin during four-day osmotic pump infusion of thyrotropin-releasing hormone and vasoactive intestinal polypeptide in rats

Pituitary prolactin (PRL) responses to 4-day continuous infusion of thyrotropin-releasing hormone (TRH) and vasoactive intestinal polypeptide (VIP) were investigated in unanesthetized male rats using Alzet osmotic minipumps. The TRH dose infused was 3.6 micrograms/day and the VIP dose was 32.8 micrograms/day. Infusion of TRH with osmotic pumps elevated the plasma PRL level compared to controls over the 4-day infusion period. However, mean levels of PRL tended to decrease during the 4-day infusion. On the other hand, continuous VIP infusion elicited a significant continuous PRL release over the 4-day infusion period. Thus, it may be said that the PRL responses to infused TRH and VIP were maintained during the 4-day infusion.     

Effect of high osmotic media on blood viscosity and red blood cell deformability

Effects of high osmotic media on the shape and deformability of RBC were examined for determining increasing factors of blood viscosity. Dog blood and Urographin (a hypertonic contrast medium) were used; the plasma osmolality was changed by Urografin suspended in blood. The viscosity was measured for normal RBC and glutaraldehyde-treated RBC suspensions with a cell volume concentration. The RBC deformability was evaluated from the difference in viscosity between the two suspensions. It was shown that normal RBC suspension increased the viscosity with increase in osmolality at high shear rate; hardened RBC suspension decreased the viscosity with increase in osmolality. It was concluded that the RBC deformability decreased with increasing osmolality.     

Hormonal regulation of translatable mRNA of glucose-6-phosphate dehydrogenase in primary cultures of adult rat hepatocytes

The quantity of translatable mRNA of glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate: NADP+ 1-oxidoreductase, EC 1.1.1.49) in primary cultures of adult rat hepatocytes subjected to different hormonal conditions was determined with a reticulocyte-lysate, cell-free system. The level of glucose-6-phosphate dehydrogenase mRNA was about 5-fold higher in the presence of insulin than in its absence. This increase of glucose-6-phosphate dehydrogenase mRNA reached a maximum 12 h after the addition of insulin. The maximum level of induction of glucose-6-phosphate dehydrogenase mRNA required 10(-8) M insulin. Glucagon and triiodothyronine had no effect on the glucose-6-phosphate dehydrogenase mRNA level. The increase of glucose-6-phosphate dehydrogenase activity correlated with the increase in level of mRNA of this enzyme. This suggests that the changes in glucose-6-phosphate dehydrogenase activity in response to the above hormonal changes are primarily due to changes in the amount of mRNA coding for this enzyme.