PubMed Health⌕ Search

Biomedical subjects

M Takeda

Publications and source records attributed to M Takeda.

At least 1,063 records · Page 59Linked to original sources
PubMed1978

Measurement of integral absorbed dose by chemical dosimeter in panoramic tomography.

As an aqueous chemical dosimeter for measuring ionizing radiation, the chemical 4,4' (5-chloro-2-thenilidene) bis [N,N-dimethylaniline], a derivative of the leuco triarylmethane compounds was used. This chemical dosimeter is an aqueous solution composed of 10(-4) M leuco compounds, 10(-4) M ferrous ammonium sulfate, 10(-4) M sodium chloride and 7 X 10(-3) M of hydrochloric acid. This solution is colourless but it becomes blue-green or bright blue after irradiation. The optical density of this solution at the main absorption peak of 635 millimicron increases linearly with the increasing x-ray dose of from 50R to 2,000 R and no dose-rate dependence is found from 13.5 R/min to 270 R/min of 60Co gamma-ray, 896 gram rads was the measured value of the integral absorbed dose per exposure in panoramic tomography (Orthopantomograph type OP-2).

Aniline Compounds↗
PubMed1978

Determination of benzo(a)pyrene in foods.

An analytical method was developed for determining benzo(a)pyrene in foods, suitable for routine use. The method consists of 4 cleanup steps: (1) alkali cleavage of sample, (2) preliminary silica gel column chromatography, (3) selective extraction with concentrated sulfuric acid, and (4) further silica gel column chromatography. Recoveries of benzo(a)pyrene added to 50 g (or 10 g) food at levels of 0.4 ppb (or 2 ppb) ranged from 70% for short-necked clam and mackeral to 85% for chicken meat. The sulfuric acid extraction step affords a simple method for isolating benzo(a)pyrene from various kinds of interfering substances which could not be separated by existing methods.

Benzopyrenes↗
PubMed1977

Azabicycloalkanes as analgetics. 3. Structure-activity relationships of 1-phenyl-6-azabicyclo[3.2.1]octanes and absolute stereochemistry of (+)-1-(3-hydroxyphenyl)-6-methyl-6-azabicyclo[3.2.1]octane and its 7-endo-methyl derivative.

A series of 53 1-phenyl-6-azabicyclo[3.2.1]octanes (1) has been tested for their analgetic and narcotic antagonist activities. Structure-activity relationships were investigated by varying the structural parameters. The most interesting compound in this series, the 1-(3-hydroxphenyl)-6,7-dimethyl derivative 8, shows the profile of a well-balanced antagonist-analgesic agent with a very mild physical dependence capacity. The absolute stereochemistry of its active enantiomer [(+)8] was established by the x-ray study and the chemical transformation to the phenylmorphan [(+)-II]. (+)-8 was stereochemically correlated also with the active enantiomer of the 7-demethyl derivatives [(+)-7] by chemical transformation and CD measurement. Certain structural and stereochemical correlations between these compounds (7 and 8) and other known antagonist-analgetics are discussed.

Analgesics↗
PubMed1977

Catecholamine metabolism in the patients with rheumatoid arthritis.

The amount of urinary catecholamine of healthy subjects and patients with rheumatoid arthritis, particularly before and after synovectomy, was studied. (1) The urinary catecholamine of patients with rheumatoid arthritis showed a lower value than that of healthy subjects. The greater the amount of intraarticularly injected steroids was and the more severe the stage and class of rheumatoid arthritis were, the lower the level of adrenaline was and the more reduced the activity of phenylethanolamine-N-methyltransferase was. (2) The level of urinary noradrenaline in patients with rheumatoid arthritis was lower than that of healthy subjects, but there was no relationship between the level of noradrenaline and the amount of intraarticularly injected steroids. Considering that noradrenaline tended to approach to the normal level as the stage of class of rheumatoid arthritis was more severe, the level of urinary noradrenaline in patients with rheumatoid arthritis seems to reflect the existence of a certain compensatory system in the enzyme system of catecholamine metabolism rather than the influence of the adrenal cortex system. (3) The urinary catecholamine was decreased after synovectomy; especially, noradrenaline level was remarkably decreased. These results suggest that catecholamine plays an important role in the appearance of pain or other clinical signs in rheumatoid arthritis.

Adult↗
PubMed1977

Uptake of 5-hydroxytryptophan by gustatory cells in the mouse taste bud.

Monoamines in the taste bud cells of the mouse circumvallate papilla were studied by fluorescence histochemistry and electron microscopy. With administration of 5-HTP (5-hydroxytryptophan) after a pretreatment with nialamide, yellow fluorescence appeared in some of the taste bud cells, while no fluorescence was observed in untreated, L-DOPA treated on serotonin treated mice. Electron microscopic study after treatment with both nialamide and 5-HTP showed small dense-cored vesicles intermingled with small clear vesicles (30-60 nm in diameter accumulated at the membranes of the gustatory cells in typical afferent synaptic contacts with nerve terminals. Definite ultrastructural change in large dense-cored vesicles (70-100 nm in diameter) could not be observed. It is suggested that the gustatory cells of the mouse take up 5-HTP and convert it to serotonin. The synaptic vesicles in the gustatory cells are believed capable of storing and releasing serotonin which presumably acts as the neurotransmitter involved in the impulse transmission from the gustatory cells to the sensory nerve fibers.

5-Hydroxytryptophan↗
PubMed1977

[Visual imagery and eye movements: effects of projective size of image on eye movements (author's transl)].

The effects of size of image on eye movements were explored. Eye movements of 18 subjects were recorded by the corneal reflection method. The subjects imagined various objects within an indicated circle of concentric circles presented externally. As the result, two types of the subjects were observed. They were as follows: (a) The majority moved their eyes within the projective angle under the 10 degrees condition and the 30 degrees condition whereas they scarcely showed eye movements under the 1 degrees condition. Asked whether a property of the stimulus belonged to the image, over 60% of the subjects, under the 30 degrees condition, showed a saccade to the proper projected part which might be considered as scanning. (b) Some subjects hardly moved their eyes under any of the conditions.

Adolescent↗
PubMed1976

Studies on the sites in histones phosphorylated by adenosine 3':5'-monophosphate-dependent and guanosine 3':5'-monophosphate-dependent protein kinases.

Adenosine 3':5'-monophosphate-dependent protein kinase (protein kinase A) purified from silkworm pupae phosphorylated five major fractions of calf thymus histone, whereas guanosine 3':5'-monophosphate-dependent protein kinase (protein kinase G) purified from the same organism reacted preferentially with H1, H2A, and H2B histones. Amino acid analysis of the phosphopeptides which were obtained by proteolytic digestion revealed that both protein kinases A and G showed the abilities to phosphorylate the same serine hydroxyl groups in H1 and H2B histones. Both protein kinases reacted with Ser-38 in H1 histone. With H2B histone as substrate protein kinase A phosphorylated Ser-32 as well as Ser-36, whereas protein kinase G reacted preferentially with Ser-32 and the reaction with Ser-36 was very slow. H3 and H4 histones were practically inactive substrates for protein kinase G. Although H2A histone has not been analyzed, the evidence has raised a possibility that protein kinase G utilizes a portion of the substrate proteins for protein kinase A.

Amino Acids↗