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T Goto

Publications and source records attributed to T Goto.

At least 919 records · Page 51Linked to original sources
PubMed1977

Source of oxygen in the CO(2) produced in the bioluminescent oxidation of firefly luciferin.

Incorporation of (18)O into the CO(2) produced in the bioluminescent oxidation of firefly luciferin was studied. In H(2) (16)O medium with (18)O(2) gas, the product CO(2) contained up to 75% C(16)O(18)O, showing that one O of the product CO(2) arose from the O(2) that oxidized luciferin. This result is consistent with a dioxetane mechanism. Analysis of the mass spectral data of the CO(2) obtained in high-enrichment H(2) (18)O medium with (16)O(2) gas indicated the presence of about 20% contaminating CO(2), which contributes approximately 70% of the total incorporated (18)O. Thus the values of incorporated (18)O in H(2) (18)O medium with (16)O(2) gas have no significance in the present context. Data obtained with luciferases of the American firefly Photinus and Japanese firefly Luciola were similar.

Journal Article↗
PubMed1977

Dihydrodipicolinate reductases from Bacillus cereus and Bacillus megaterium.

Dyhydrodipicolinate reductases were purified 100-fold from crude extracts of B. cereus and B. megaterium and their properties were compared with those of the reductase from B. subtilis. The molecular weights of the reductases of B. cereus and B. megaterium were fount to be 155,000 and 150,000, respectively. These reductases were shown to be free of flavin, unlike the B. subtilis enzyme, which contains flavin. Both NADPH and NADH acted as coenzymes for these two reductases. NADPH being three or four times more effective than NADH. The Km values for NADPH and dihydrodipicolinate were 8 micrometer and 62 micrometer, respectively, with B. cereus reductase, and 13 micrometer and 59 micrometer with B. megaterium reductase. The pH optima of the enzymes from B. cereus and B. megaterium were pH 7.4 and 7.2, respectively. The reductases were inhibited by dipicolinate noncompetitively with respect to dihydrodipicolinate and the Ki values were 85 micrometer and 140 micrometer, respectively. Lysine and diaminopimelate were not inhibitory. The properties of the reductases from B. cereus and B. megaterium were similar, but they differed considerably from those of the B. subtilis enzyme. However, all three Bacillus reductases were markedly inhibited by dipicolinate, unlike the enzyme from E. coli.

Bacillus cereus↗
PubMed1976

Structure of wye (Yt base) and wyosine (Yt) from Torulopsis utilis phenylalanine transfer ribonucleic acid.

A fluorescent base wye (Yt base) was isolated from Torulopsis utilis tRNAPhe. The structure was established as 4,9-dihydro-4,6-dimethyl-9-oxo-1H-imidazo[1,2-alpha]purine based on ultraviolet (uv), nuclear magnetic resonance (NMR), and mass spectra, and by direct comparison with synthetic material. The nucleoside, wyosine (Yt), was isolated from purified tRNAPhe by enzymatic degradations followed by column and thin-layer chromatographies. The structure of wyosine is proposed as 3-ribofuranosyl-4,9-dihydro-4,6-dimethyl-9-oxo-1H-imidazol[1,2-alpha]purine (the ribosyl group is attached to the N-9 position of guanine nucleus) on the basis of comparison with model compounds.

Candida↗
PubMed1976

Surgical treatment of tricuspid insufficiency in patients undergoing mitral valve replacement.

During the past eight years, 46 of the 106 patients who underwent mitral valve replacement were associated with tricuspid insufficiency. No surgical correction was performed (14 cases) in cases of slight tricuspid insufficiency. Tricuspid annuloplasty (11 cases) or valve replacement (21 cases) was employed according to the severity of insufficiency. In the non-repair group, the mortality rate was fairly low (21 per cent), but the postoperative status was the least satisfactory by the NYHA classification. Tricuspid insufficiency was significantly reduced only in two of these 14 cases after the mitral valve replacement. In the tricuspid annuloplasty group, although the technique of tricuspid annuloplasty did not always correct insufficiency completely, only one patient died of residual insufficiency. The cardiac output measured with Minnesota Impedance Cardiograph increased postoperatively in proportion to stress in this group. In the tricuspid valve replacement group, cardiac catheterization studies revealed hemodynamic improvement at rest in all, but cardiac output during exercise remained unchanged or decreased in some cases. Now we consider that tricuspid insufficiency with advanced mitral valve disease, even of a slight degree, should be surgically treated and that annuloplasty has more obvious hemodynamic benefits than valve replacement.

Adult↗
PubMed1976

[An epidemiologic study on vibration hazards among workers at the state forests in Kyushu (author's transl)].

There are only very few reports of epidemiologic analysis on vibration hazards among the workers at the state forests of Japan since 1970. It was necessary to perform investigations on the state of vibration hazards anew, through some labor hygienic policies on the prevention of the hazards, such as regulation of the time of using vibrating tools, had been executed to some extent since 1970. From the data of physical check-ups of 861 chain saw users of 24 District Forestry Offices in Kumamoto, Miyazaki and Kagoshima Prefectures in the south of Kyushu, the transition of vibration hazards was studied by using the incidence and prevalence of Raynaud's phenomenon and paresthesia of the fingers as indices. From the yearly transition of the hazards, a tendency was observed of increasing patients with vibration syndrome during the period from 1962 to 1970 when countermeasures on vibration hazards were not sufficient. However, since 1970 the occurrence of Raynaud's Phenomenon has shown a tendency to decrease among the workers with short history of using chain saw and the occurrence of paresthesia of the fingers as indices. From the yearly transition of the hazards, a tendency was observed of increasing patients with vibration syndrome during the period from 1962 to 1970 when countermeasures on vibration hazards were not sufficient. However, since 1970 the occurrence of Raynaud's Phenomenon has shown a tendency to decrease among the workers with short history of using chain saw and the occurrence of paresthesia of the fingers to increase among those with long history. The results are suggestive of making clear the pathophysiology of vibration hazards.

Fingers↗
PubMed1976

[A new modified wick catheter for measurement of the brain tissue pressure-an evaluation of static and dynamic properties of the catheter (author's transl)].

The interstitial pressure of the brain was measured with wick catheter by Lassen in 1972. But original wick catheter inserted into the brain tissue does not always measure the real interstitial pressure as indicated by experimental results of Brodersen, because, the interstitial pressure is always affected by solid pressure such as cells in the brain tissue, in the condition of which surrounded by positive CSF pressure in the semiclosed skull box. It is not yet clarified what kinds of the pressure are measured by wick catheter method in the brain tissue. The size of wick catheter is 300-500 times as large as the width of interspace of the brain tissue and the catheter is easily obstructed by brain tissue. Therefore, a new, modified wick catheter is made for improvement of these problems which is observed by using original wick catheter. The new, modified catheter has 0.4 mm inside diameter and 10 cm length. The tip of catheter is closed and 6 small side holes(0.1 mm0)are made. Inside the catheter, several pieces of 0.04 mm diameter nylon threads are inserted as shown in figure 1, and the catheter is filled up with the cerebrospinal fluid. In this paper, the structure of the new, modified catheter is demonstrated, and the brain tissue pressure is measured, comparing with the results of the original wick catheter to test the function of the new, modified catheter. The results of measurement of the brain tissue fluid pressure with the new, modified catheter are as follows; 1) The brain tissue fluid pressure is relatively constant and shows a positive pressure of 5.2 mmHg. 2) As there are few blocking effects in the catheter, the new, modified catheter is useful for the measurement of the brain tissue fluid pressure for a long time. 3) The brain tissue fluid pressure is not altered by the number's of nylon threads in the catheter at static condition, but movement of brain tissue fluid pressure with respiration is a little dumped by the increased conductancy with the numbers of nylon threads in the catheter. 4) The tissue fluid pressure affected by the viscosity and osmolarity of the fluid in the catheter, CSF should be used for correct measurement. According to these results, it might be concluded that the new, modified wick catheter is better than the original wick catheter regarding prevention of obstruction of the catheter by brain tissue fragments, artifacts which causet by movement of wick fibers, measurement of brain tissue fluid pressure for a long time and clarify the resistance of catheter to pressure conductancy.

Animals↗