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Biomedical subjects

S Hata

Publications and source records attributed to S Hata.

At least 181 records · Page 10Linked to original sources
PubMed1986

Atypical ocular bobbing in acute organophosphate poisoning.

Atypical ocular bobbing resulted from an intentional poisoning from dimpylate (Diazinon), an organophosphate compound. In discussing the possible foci and mechanism for atypical ocular bobbing associated with acute organophosphate poisoning, we suggest acetylcholine as a neurotransmitter substance within the ocular motor pathway. A literature review has not shown any previous reported cases with this sign.

Adult↗
PubMed1986

Effects of dietary histidine and methionine loading in rats with a portacaval shunt.

To elucidate disturbances of brain amine metabolism in hepatic coma, the effects of dietary histidine and methionine loading on the brain levels of amino acids and transmitter amines and on behavior were examined in rats with a portacaval shunt (PCS rats). Surgical construction of a portacaval shunt exaggerated the increase in brain histamine caused by dietary histidine loading 4 weeks after operation. Although the marked increase in the brain level of methionine itself did not affect on the brain levels of catecholamines, serotonin, and histamine, brain level of 5-HIAA was decreased in PCS rats on methionine-enriched diet. Diminished spontaneous activity was observed in PCS rats on either diet, which could not be related to the disturbance of brain amine metabolism caused by excess histidine and methionine. These results indicated that histamine was involved in the derangement of brain amine metabolism in PCS rats, and that direct effect of dietary methionine loading on the brain levels of transmitter amines was not observed in PCS rats. The etiological relation of these substances to hepatic coma should be further investigated.

Amino Acids↗
PubMed1986

Temporary low oxygen conditions for the formation of nitrate reductase and nitrous oxide reductase by denitrifying Pseudomonas sp. G59.

Formation of nitrate reductase (NaR) and nitrous oxide reductase (N2OR) by a Pseudomonas sp. G59 did not occur in aerobic or anaerobic conditions, but was observed in a microaerobic incubation in which an anaerobically grown culture was agitated in a sealed vessel initially containing 20 kPa oxygen in the headspace. During the microaerobic incubation, the oxygen concentration in the headspace decreased and dissolved oxygen reached 0.1-0.2 kPa. NaR activity was detected immediately and N2OR activity after 3 h of incubation irrespective of the presence or absence of NO3- or N2O. In the presence of NO3-, NO2- was accumulated as a major product, but N2O was observed in low concentrations only after N2OR appeared. After microaerobic incubation for 3 h, N2OR formation continued even anaerobically in an atmosphere of N2O. In contrast, Escherichia coli formed NaR not only microaerobically but also anaerobically. However, NaR formation by E. coli was inhibited by sodium fluoride under anaerobic, but not under microaerobic conditions. The Pseudomonas culture did not possess fermentative activity. It is suggested that the dependence on microaerobiosis for the formation of these reductases by the Pseudomonas culture was due to an inability to produce energy anaerobically until these anaerobic respiratory enzymes were formed.

Aerobiosis↗
PubMed1986

Multifocal ventricular ectopic complexes possibly related to diuretic induced hypokalemia in a woman with the long QT syndrome.

A 40-year-old housewife was observed with chief complaints of syncope and palpitation. The electrocardiogram indicated premature ventricular ectopic complexes of the torsade de pointes. Serum potassium level was low because of thiazide-induced hypokalemia for the treatment of transient hypertension. Even after the disappearance of threatening ventricular arrhythmias and normalization of serum potassium level, prolongation of QT interval was continuously persisted. Thiazide induced hypokalemia might have some roles on producing ventricular ectopic activity in prolonged QT syndrome as shown in our case.

Adult↗
PubMed1985

Fatty acid composition and Shwartzman activity of lipopolysaccharides from oral bacteria.

The composition and the nature of the linkage of fatty acids and the Shwartzman activity of lipopolysaccharide (LPS) preparations derived from oral gram-negative bacteria including Bacteroides gingivalis, Bacteroides loesheii, Eikenella corrodens, Fusobacterium nucleatum, and Actinobacillus actinomycetemcomitans were examined. 3-Hydroxylated and nonhydroxy fatty acids of various chain lengths were found in all of the LPS preparations. All nonhydroxy fatty acids were found to be ester-bound, and part of the 3-hydroxy fatty acids in the LPS of B. gingivalis, E. corrodens, F. nucleatum, and A. actinomycetemcomitans were shown to be involved in ester linkage. It was also suggested that the hydroxy group of the ester-bound 3-hydroxy fatty acid of the LPS of F. nucleatum and A. actinomycetemcomitans is at least partly substituted by another fatty acid, but in the LPS of B. gingivalis and E. corrodens it is not. The main amide-linked fatty acid of the LPS of B. gingivalis, E. corrodens, F. nucleatum, and A. actinomycetemcomitans was 3-hydroxyheptadecanoic, 3-hydroxydodecanoic, 3-hydroxyhexadecanoic, and 3-hydroxytetradecanoic acid, respectively. The results of the Shwartzman assay showed that the E. corrodens LPS was the most active among the preparations tested, and that the Shwartzman toxicity of Bacteroides LPS is extremely low.

Actinobacillus↗
PubMed1985

Density of dopa-positive melanocytes in dyschromatosis symmetrica hereditaria.

Dyschromatosis symmetrica hereditaria, one of the hereditary diseases characterized by the presence of pigmented and hypopigmented spots on the extremities, was studied by the splitting dopa stain on the hypopigmented area. There were 190 +/- 58/mm2 dopa-positive cells, i.e. less than the normal value of the Japanese population. This suggests that the pigment anomaly in this disease may be due to the small number of melanocytes.

Biopsy↗
PubMed1985

Unusual pigmentation on the skin over trunk bones and extremities.

6 young people (19-31 years old) exhibited unusual light or dark brown, ill-circumscribed or reticular pigmentation distributed over protrudent bones. 5 of them have been using nylon towels and scrub brushes for over 3-10 years. Biopsy specimens showed that the amount of melanin granules in the basal layer was increased and melanophages were scattered in the upper dermis. Inflammatory infiltrates were minimal.

Adult↗
PubMed1985

[Quantitative assessment of regurgitant fraction in aortic regurgitation: comparison of two-dimensional Doppler echocardiography with other methods].

To determine proper operative procedures for aortic regurgitation (AR), we attempted to evaluate the severity of AR by two-dimensional Doppler echocardiography (TDE), using 15 mongrel dogs with experimentally-induced AR. Furthermore, the left ventricular (LV) suction method was investigated for the significance in estimating the severity of AR, cardiac outputs were measured by the thermodilution technique, TDE, and electromagnetic flowmeter (EMF). The values obtained by each method were compared. In dogs with AR, regurgitant fraction (RF) was calculated from stroke volumes obtained by TDE and EMF, as follows: RF [TDE] = (LVO-RVO)/LVO (LVO: left ventricular output; RVO: right ventricular output) RF [EMF] = [total stroke volume (T)-effective stroke volume (E)]/T The effects of alterations in afterload and pump flow rates on regurgitant fractions and regurgitant volumes measured by the LV suction method were also studied. The following results were obtained: Good correlations were observed between RVO and LVO measured by TDE, and those measured by the thermodilution technique and EMF, respectively. In dogs with AR, regurgitant fractions measured by TDE correlated well with those measured by EMF. These results strongly suggested that the Doppler index (RF) was accurate and useful for estimating the severity of AR clinically. Regurgitant volumes measured by the LV suction method were not influenced by the pump flow rate, and they correlated well with square root values of the mean diastolic pressure in the aorta. In the LV suction method, Bernoulli's theorem held good between the regurgitant volumes and the mean diastolic pressures in the aorta of the dogs with AR. Considering the factors of mean diastolic pressure in the aorta and diastolic time, regurgitant volumes measured by EMF in the beating heart showed excellent agreement with those measured by the LV suction method in ventricular fibrillation. Therefore, to evaluate quantitatively the pathophysiological changes of the aortic valve in patients with AR, we should estimate the severity of AR using regurgitant volumes corrected for the cardiac cycle at the same mean diastolic pressure in the aorta.

Animals↗
PubMed1984

Histochemical characterization of mucosubstances in synovial sarcoma.

Six cases of synovial sarcoma were examined histochemically in order to clarify the components of mucosubstances in the tumor tissues. The tumors were classified into 1) monophasic type, 2) predominantly monophasic type with focal biphasic differentiation, and 3) biphasic type. The former two groups and sarcomatous areas in the biphasic tumors contained various amounts of hyaluronic acid, chondroitin sulfate, and, in some cases, heparitin sulfate. By contrast, the epithelioid regions in the biphasic-type tumors had periodic acid-Schiff-positive glycoproteins which contained various amounts of sialic acid, in addition to hyaluronic acid and chondroitin sulfate. The significance of the presence of glycoproteins in the mesenchymal tumors is emphasized. It seems likely that the synovial sarcomas contain various kinds of mucosubstances and that sensitivity to hyaluronidase treatment is not necessarily the diagnostic criterion of synovial sarcoma.

Adult↗
PubMed1984

Detection of left atrial thrombi in man using indium-111 labelled autologous platelets.

A scintigraphic technique using indium-111 labelled platelets to detect left atrial thrombi was used in 28 patients, 14 of whom had mitral valve disease and 14 combined valve disease. Imaging was performed in the anterior, right anterior oblique (45 degrees), and left lateral views on the day of injection and thereafter at one or two day intervals for a maximum of four days. When scintiphotos obtained in two or three views 72 or 96 hours after the platelet injection showed "hot spot areas" within the left atrial pool and indium-111 activity in these areas did not decrease with time they were interpreted as positive for thrombi. Of 28 patients, seven had positive platelet images by this criterion; of these, three underwent surgery and were found to have left atrial thrombi. One patient died, and a thrombus was found at necropsy. The remaining 21 patients had normal scintiphotos; of these, seven had no thrombi at operation and one had false negative images. The diagnostic accuracy of platelet scintigraphy by this criterion of positivity in the 12 patients in whom surgical or postmortem confirmation of thrombi could be obtained was 92%. These results indicate that this technique is a promising method for detecting active left atrial thrombi.

Adult↗