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Biomedical subjects

T Tamura

Publications and source records attributed to T Tamura.

At least 1,387 records · Page 77Linked to original sources

Proton nuclear magnetic resonance identification and discrimination of side chain isomers of phytosterols using a lanthanide shift reagent.

Proton nuclear magnetic resonance (1H-NMR) spectra at 90 MHz were measured for a number of side chain isomers of phytosterols (sterols with a C8H17 side chain, and delta 24-, 24-methylene, delta 22-, 24-ethylidene, 24-methly, 24-ethyl, 24-methyl-delta 22-, 24-ethyl delta 22-, and 24-ethyl-delta 22,25(27)-sterols) with or without a lanthanide shift reagent, tris[1,1,1,2,2,3,3 - heptafluoro - 7,7 - dimethyloctane - 4,6 - dionato]ytterbium, Yb(fod)3, and the effect of Yb(fod)3 on the side chain methyl protons is discussed. The change of the chemical shifts induced Yb(fod)3 for the side chain methyls was expressed in terms of the induced shift ratios (ISR values), i.e., the ratios of the induced chemical shifts of the respective side chain methyls to that of the fastest moving side chain methyl. The ISR values were sentitive to minor structural and stereochemical differences, but almost independent of ring structures and of substrate concentrations, thus providing confirmatory evidence for the side chain structures. Also, the Yb(fod)3-induced spectral patterns observed in the high-field methyl region bore the fingerprints of the side chain structures. Several isomeric pairs of sterols, which differ only in the geometry of double bonds or the absolute configuration at C-24 in the side chain, i.e., cis- and trans-isomers of delta 22-and 24-ethylidene sterols, 24R/alpha- and 24S/beta-methyl sterols, 24R/alpha- and 24S/beta-ethyl sterols, and 24S/alpha- and 24R/beta-ethyl-delta 22-sterols, could be differentiated from each other under the influence of Yb(fod)3, even though they were measured at 90 MHz.

Chemical Phenomena↗

Sequential changes of orthogonal electrocardiograms in progressive muscular dystrophy of the Duchenne type.

Sequential changes of orthogonal electrocardiograms in 70 patients with progressive dystrophy of the Duchenne type (PMD) were investigated. The patients were classified into eight stages from the mildest, S(1), to the severest, S(8), according to Swinyard-Deaver's criteria. The most prominent finding was a progressive reduction in R wave amplitude in Lead X (Rx) with advancing severity. It was considered that loss of electrical activity in the left ventricular free wall might be mainly responsible for the reduction in the Rx amplitude. An abnormal Q wave was frequently observed in each stage. Its occurrence remained essentially unchanged with the progression of PMD. Thus, the presence of a deep Q wave cannot serve as an index for assessing the heart involvement, but rather, we conclude that a reduction of the Rx amplitude can be a useful criterion for estimating the extent of cardiac involvement in PMD.

Activities of Daily Living↗

Orthogonal electrocardiographic study on progressive muscular dystrophy of the Duchenne type.

An attempt was made to investigate the incidence and significance of high frequency notches and slurs on the QRS complex in patients with progressive muscular dystrophy of the Duchenne type (PMD). The patients were classified into eight stages from the most mild, S(1), to the most severe, S(8), according to Swinyard-Deaver's criteria. Cases where the sum of high frequency notches in the combined leads exceeded none were generally limited to those more advanced than stage S(4). Also, the sum of the notch count tended to be higher in S(5) to S(6) than in the remaining groups and to be lower in the milder cases, S(1) to S(4), and most severe cases, S(7) and S(8). It should be emphasized that cases in groups S(7) and S(8) who had a history of congestive heart failure and/or developed congestive heart failure during the observation period, tended to show a smaller number of notches. High frequency slurs showed almost the same tendencies as the high frequency notches. It is thus anticipated that a significant increase or decrease in the number of notches and slurs on the QRS complex may be suggestive of more intense myocardial derangement.

Adolescent↗

IgM and IgG response to sheep red blood cells in mouse hepatitis virus-infected nude mice.

In nude mice which originally had no ability to respond to sheep red blood cells, an enhanced response to the same antigen with IgM-IgG switching was demonstrated during subacute infection with mouse hepatitis virus. IgM antibody-producing cells in the spleen were detected at days 2 to 6 after the antigen injection and IgG antibody-producing cells appeared at day 6 or later. The secondary IgG response, though not remarkable, was recognized after reinjection of the antigen 10 days after the first injection.

Animals↗

The role of macrophages in the early resistance to mouse hepatitus virus infection in nude mice.

Nude mice which had received intraperitoneal injection of silica simultaneously with infection of mouse hepatitis virus, NuU strain, died of severe necrotic hepatitis within 2 weeks postinfection, whereas those having received no silica survived for 3 weeks or more after challenge. Silica given day 4 postinoculation had no effect. The virus titers of the liver and spleen at day 4 as well as serum interferon levels at day 2 were much higher in silica-treated mice than those without silica treatment. At day 2 or 3 postinoculation, silica-treated mice were found to have a considerable number of necrotic foci in the liver with some neutrophil and lymphocyte infiltration, and viral antigen was present in the cytoplasm of some hepatocytes around necrotic foci. In contrast, those without silica treatment showed only some necrotic foci with some lymphocyte infiltration. Viral antigen was detected only in a few littoral cells but not in hepatocytes. The role of macrophages in the resistance at early stage of inection in nude mice is discussed.

Animals↗

Study of respiratory influence on the intensity of heart sound in normal subjects.

The amplitudes of the first and second heart sounds were recorded during quiet natural breathing in 31 normal subjects. A total of 3,656 and 3,016 heart beats were available at the apex and pulmonic areas respectively. The intensities of the first and second heart sounds were found to be increased during expiration. This respiratory tendency in the heart sounds was less prominent during the transitional phase between expiration and inspiration. Therefore we suggest that respiratory changes in heart sounds should be evaluated with a heart beat located at or close to the center of each inspiration and expiration. Respiratory alteration in the intensity of heart sounds is one of the commonest auscultatory pitfalls. Auscultatory evaluation of the intensity of heart sounds should thus be performed carefully, with the respiratory changes kept in mind.

Adolescent↗

Immunohistologic findings in the glomerular crescents in various renal diseases.

Renal tissues from 37 patients with glomerulopathies involving glomerular crescents were investigated using an immunofluorescence technique. Immunohistologic findings revealed two kinds of crescents, those with fibrinogen deposits (active), and those without (inactive). The degree of IgG deposition in glomeruli with active crescents was much higher than in glomeruli with inactive crescents in acute glomerulonephritis (AGN) and chronic glomerulonephritis (CGN). Active crescents were observed only in biopsy specimens taken within three months after the onset of acute glomerulonephritis or the acute exacerbation of chronic glomerulonephritis. These findings suggest that in AGN and CGN active crescents occur in an earlier stage of glomerular lesions and a more active stage in the immunological process than inactive crescents. The significance of active crescents in SLE, diabetic nephropathy and nephropathy associated with rheumatic arthritis was not evaluated due to the small number of patients.

Acute Disease↗

Deleterious effect of short-term exposure to Coca-Cola on rats.

Semiacute toxicity of cola fluid, Coca-Cola, conducting for approximately a month in rats, was studied. A trend of cariogenicity of Coca-Cola was strongly indicated. When the fluid was given ad libitum, decarbonized Coca-Cola and carbohydrate solution, consisted 8% of glucose and 3.5% of sugar and then adjusted pH to 2.4 with oxalic acid, were consumed 2 to 3 times greater than the control (water). A hyperuresis was observed as the result of great consumption of liquid, but no liver nor kidney degeneration was observed by histopathological examination. The diet consumption of the groups of Coca-Cola and carbohydrate solution was approximately a half of the control, water. However, when a complete diet was given, no physiological difference in time was observed, except in diarrhea and depression of hair gloss in Coca-Cola group.

Animals↗

Etiological relation between Korean hemorrhagic fever and epidemic hemorrhagic fever in Japan.

The first case of epidemic hemorrhagic fever in Japan was seen in Osaka in 1960. The etiologic agent of this disease has not yet been isolated, but a close etiologic relation between Korean hemorrhagic fever and epidemic hemorrhagic fever in Japan has been suspected because of similarities in the clinical and pathological pictures of the two diseases. This relation has now been confirmed serologically by demonstrating specific immunofluorescent antibodies to Korean hemorrhagic fever virus in 19 of 20 sera obtained from subjects 7 to 17 years after an acute attack of epidemic hemorrhagic fever.

Adolescent↗