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Biomedical subjects

T Ochi

Publications and source records attributed to T Ochi.

At least 289 records · Page 16Linked to original sources
PubMed1986

Quantitative analysis of acute myocardial infarction using single photon emission computed tomography using technetium-99m pyrophosphate.

The usefulness of single photon emission computed tomography (SPECT) using technetium-99m pyrophosphate (99mTc-PPi) was evaluated in 15 patients with acute myocardial infarction. SPECT was performed with a rotating gamma camera after conventional planar images were made. Infarct size was measured from transaxial images of myocardial pyrophosphate uptakes. In each slice, the boundary was defined by subtracting 70 percent of the maximal counts and the number of voxels automatically counted. This subtraction rate was determined by phantom study and by comparing SPECT using 99mTc-PPi with thallium-201-gated myocardial scintigraphy (201Tl gated SPECT). The planar images showed diffuse uptakes in two of the 15 patients, and in these cases it was difficult to detect the infarct site. In contrast, SPECT images clearly imaged the infarct site consistent with the electrocardiographic findings, and they were definitely separated from the uptakes in the bones in all cases. Infarct size, ranging from 3.4 ml to 78.3 ml, correlated well with cumulative creatine kinase release (r = 0.84, p less than 0.01, y = 772x + 13900). Correlation of infarct size with peak serum creatine kinase level was also significant (r = 0.66, p less than 0.01, y = 10.6x + 693). In conclusion, SPECT with 99mTc-PPi is a useful means of investigating the spatial distribution of pyrophosphate uptake and of evaluating the size of myocardial infarction.

Aged↗
PubMed1985

Adverse effects of atrial fibrillation and syncope induced by calcium-channel blockers in hypertrophic cardiomyopathy.

Calcium-channel blockers are useful for the treatment of hypertrophic cardiomyopathy (HCM), but, their adverse effects, especially, those of diltiazem, have not been of much concern. Forty patients with HCM were treated with calcium-channel blockers such as nifedipine, diltiazem, and verapamil. Atrial fibrillation was induced by diltiazem in two patients and verapamil induced syncope in one patient. The clinical and hemodynamic characteristics of the patients were as follows. All of them had the obstructive type of HCM (HOCM). One of them had a high pressure gradient of the left ventricular outflow tract and the others had earlier onset. In these patients, the left atrial overload seemed to be severe. The vasodilating action of calcium-channel blockers decreases the systemic pressure and in turn, may increase the pressure gradient and the left ventricular end-diastolic pressure. The elevated left ventricular end-diastolic pressure causes the left atrial overload which could be at risk of atrial fibrillation in patients with HCM. Therefore, calcium-channel blockers should be used carefully in peculiar cases of HOCM.

Adult↗
PubMed1985

The effects of cell cycle position on the cytotoxicity and mutagenicity of benzo(a)pyrene in cultured Chinese hamster cells.

The induction of cytotoxicity and mutation to 6-thioguanine resistance (6TGr) by S9-activated benzo(a)pyrene (B(a)P) was studied in asynchronized and synchronized Chinese hamster V79 cells. After treatment of asynchronized populations with B(a)P (0.25-2 micrograms/ml) in the presence of S9 for 3 h, the number of 6TGr cells increased. The increase was concentration-dependent up to 2 micrograms/ml, and was accompanied by a concomitant concentration-dependent decrease in cell survival. Synchronized cells were treated with B(a)P for 2 h at 2-h intervals after release from the G1/S block by hydroxyurea (HU). The cytotoxicity of 2 micrograms/ml of B(a)P was maximal at 0 h after HU release, i.e., G1/S phase, and also at 2 h after HU release, i.e., early S phase. Thereafter, it decreased with the progression of the cell cycle. Similarly, treatment with B(a)P at 0 h and 2 h after HU release resulted in the maximum incidence of 6TGr mutants, after which the incidence showed a decrease from 4-10 h after HU release. These results indicate that the cells in G1/S and early S phase are highly susceptible to cytotoxic and mutagenic damage induced by B(a)P and suggest the presence of a specific hot spot in the cell cycle for mutagenesis by the carcinogen B(a)P in cultured hamster cells.

Animals↗
PubMed1985

Participation of active oxygen species in the induction of chromosomal aberrations by cadmium chloride in cultured Chinese hamster cells.

The effect of various scavengers of active oxygen species on the induction of chromosomal aberrations by cadmium chloride (CdCl2) was investigated in cultured Chinese hamster V79 cells. Incidences of chromosomal aberrations by CdCl2 were partially or fully reduced by the presence of catalase, mannitol (a scavenger of hydroxyl radicals) and butylated hydroxytoluene (BHT, an antioxidant). These findings may indicate participation of the active oxygen species such as hydrogen peroxide (H2O2) or hydroxyl radicals in the clastogenicity of cadmium. In contrast, superoxide dismutase (SOD) and dimethylfuran (a scavenger of singlet oxygen) did not influence incidences of chromosomal aberrations by CdCl2. These results suggest that superoxide anion and singlet oxygen are not directly involved in the clastogenicity of the metal. The presence of aminotriazole (an inhibitor of catalase) increased incidences of chromosomal aberrations by CdCl2. This emphasizes participation of H2O2 in the clastogenicity of cadmium.

Animals↗
PubMed1985

Difference in myocardial characteristics between hypertrophic cardiomyopathy and myocardial hypertrophy due to essential hypertension.

To investigate the qualitative difference in myocardial hypertrophy that exists between hypertrophic cardiomyopathy (HCM) and essential hypertension (HT), we measured the mean wall thickness (MWT), the early diastolic time intervals (IIA-MVO time: from the second heart sound to the point of mitral valve opening, MVO-O time: from MVO to the O point of apexcardiogram) and the MVO-O/IIA-MVO ratio. The MWT in HCM and HT was measured by biventriculogram and echocardiogram, respectively. The MWT showed no significant difference between HT (13.1 +/- 3.0 mm) and non-obstructive type of HCM (14.8 +/- 3.7), but the MWT in obstructive type (1.08 +/- 0.24) was significantly thinner than that in HT. As the MWT increased, both IIA-MVO and MVO-O time were prolonged in both groups. But the mode of prolongation was quite different. In HT, the prolongation of the IIA-MVO time was almost always greater than that of the MVO-O time. In HCM, the prolongation of the latter was greater than that of the former. The MVO-O/IIA-MVO ratio in HT was significantly less than that in normal subjects, but those in HCM were significantly greater. These findings suggest that the differences in the early diastolic time intervals between HCM and HT are not due to the magnitude of the left ventricular hypertrophy, but due to myocardial characteristics.

Adult↗
PubMed1985

[The antiinflammatory effect of budesonide].

The systemic and topical antiinflammatory activities of budesonide (B) were studied in rats and mice and compared with those of commercially available steroids. Betamethasone 17-valerate (BV) was used as the main reference compound, and fluosinolone acetonide (FA), hydrocortisone 17-butyrate (HB) and hydrocortisone 21-acetate (HA) were also used. B given systemically had stronger antiinflammatory effect than BV on carrageenin edema, cotton pellet granuloma, adjuvant arthritis, croton oil edema, PCA reaction, Arthus reaction, contact hypersensitivity and histamine or serotonin skin reaction. The potency of antiinflammatory activity of the 5 compounds in carrageenin edema, croton oil edema and contact hypersensitivity tests was in the order of FA, B, BV, HB and HA. B given locally also produced stronger antiinflammatory effects than BV on carrageenin edema, cotton pellet granuloma, croton oil edema and contact hypersensitivity. The order of potency of the 5 compounds in carrageenin edema, croton oil edema and contact hypersensitivity tests was the same as by systemic application. In general, the ratio of the dose required to cause atrophy of the thymus and adrenals to the dose required to produce the antiinflammatory effect was the greatest with B by both systemic and local application. The results suggest that B has a stronger antiinflammatory activity with fewer systemic side effects than conventional steroid compounds.

Adrenal Gland Diseases↗
PubMed1985

[The anti-inflammatory effect of auranofin].

The anti-inflammatory effects of auranofin were studied and compared with those of indomethacin, gold sodium thiomalate (GST) and D-penicillamine. Auranofin was active as indomethacin in inhibiting carrageenan induced paw edema in rats, but was less potent than indomethacin in inhibiting UV-induced erythema in guinea pigs. Auranofin inhibited Arthus type paw edema and reverse PCA reaction in rats, on which indomethacin was ineffective. The inhibitory activity of auranofin on adjuvant arthritis was weaker than that of indomethacin. In in vitro experiments, auranofin did not show any suppression of cyclooxygenase activity, but was capable of suppression of lysosomal enzyme release and chemotaxis of neutrophils and macrophages. In addition to these anti-inflammatory activities, auranofin had almost equal anti-analgesic and anti-pyretic activity to that of indomethacin. The above results indicated that the anti-inflammatory profiles of auranofin and indomethacin differ, so we can expect new therapeutic activities of auranofin. GST had similar anti-inflammatory and anti-analgesic profiles to those of auranofin; however, the activities were less potent than auranofin and devoid of anti-pyretic activity. D-penicillamine did not show any anti-inflammatory, anti-analgesic or anti-pyretic activity.

Animals↗
PubMed1985

The analysis of systolic and diastolic time intervals: a more sensitive non-invasive method in the assessment of left ventricular dysfunction in the patients with essential hypertension.

Time indices and volumetric parameters were investigated in patients with essential hypertension subdivided into three groups according to the WHO stage classification. The ratio of ejection time (ET) and pre-ejection period (PEP), ET/PEP remained within normal range in WHO-I but decreased significantly in WHO-II and reached extremely low values in WHO-III. ET did not change in WHO-I and WHO-II but became significantly reduced in WHO-III. Prolongation of PEP in WHO-II and WHO-III increased with progression of hypertensive stage. Isovolumic relaxation time (IRT) showed the same pattern as the prolongation of PEP; positive correlation between PEP and IRT was observed (r=0.55). On the other hand, significant changes of volumetric parameters were only observed in WHO-III. These results indicated that the time indices were a more sensitive parameter than the volumetric ones in the assessment of left ventricular dysfunction in the patients with essential hypertension.

Adult↗
PubMed1985

Release of hydrogen peroxide from polymorphonuclear leukocytes stimulated with lambda-carrageenan.

The production of hydrogen peroxide (H2O2) by polymorphonuclear leukocytes (PMNs) that are exposed to lambda-carrageenan (100 micrograms/ml) and 12-0-tetradecanoylphorbol-13-acetate (TPA, 100 ng/ml) was measured by a colorimetric method. After a lag period of 15 min the release of H2O2 by carrageenan-stimulated PMNs increased until a plateau level was reached at 60 min. The amount of H2O2 released was dependent on the number of cells in well or the concentration of carrageenan, reaching a maximum production of H2O2 at 5 X 10(6) cells per 3-cm dish and 100 micrograms/ml of carrageenan, respectively. The maximum amount of released H2O2 from carrageenan-treated PMNs was approximately 11 n moles/hr/10(6) cells. In contrast, TPA-stimulated PMNs released H2O2 linearly for 60 min without a lag period and produced a maximum of 60 n moles/hr/10(6) cells. These results show that lambda-carrageenan stimulates an oxidative burst from in vitro PMNs and furthermore suggest that these carrageenan-stimulated PMNs release sufficient H2O2 to induce DNA damage in mammalian cells.

Animals↗
PubMed1984

Serum C1q levels as a prognostic guide to articular erosions in patients with rheumatoid arthritis.

C1q was measured serially by single radial immunodiffusion in 54 rheumatoid arthritis (RA) patients over a period of more than 5 years, and values were correlated with laboratory, radiographic, and clinical findings. The number of joints with erosion (NJE) was determined retrospectively from radiographs of patients who had RA of greater than 7 years duration. In patients with clinically "burned out" RA, C1q levels were not statistically different from those of healthy adults. During the period of active disease, each patient's C1q level remained very constant, irrespective of erythrocyte sedimentation rate, C-reactive protein (CRP) level, or whether the RA was active or in remission. No sustained correlation was found between the C1q level and the other 2 acute phase reactants, but patients with C1q levels of at least 250 micrograms/ml showed a positive CRP over a period of years, in contrast to those with C1q levels below 250 micrograms/ml. Patients with an initial C1q above 250 micrograms/ml had more erosive RA when compared with those having C1q levels below 250 micrograms/ml. These data suggest that active RA can be classified into two subsets by C1q levels, one with persistent inflammation and a high NJE and another without persistent inflammation and with a low NJE.

Adolescent↗
PubMed1984

Noninvasive evaluation of left ventricular function by systolic time intervals in essential hypertension with angina pectoris.

In order to clarify the hemodynamic characteristics in essential hypertension (HT) with angina pectoris (AP), systolic time intervals (STIs) were measured in 13 normal subjects (N), 23 patients with AP, 43 HT (WHO stage I: 13, WHO stage II: 23, WHO stage III: 7) and 19 HT with AP (WHO I: 9, WHO II: 10). The ET/PEP ratio was 2.41 +/- 0.24 in N, 2.70 +/- 0.34 in AP (p less than 0.02, vs N), 2.25 +/- 0.29 in WHO I, 2.13 +/- 0.25 in WHO II (p less than 0.01, vs N), 1.54 +/- 0.37 in WHO III (p less than 0.001, vs N), 2.68 +/- 0.32 in WHO I with AP (p less than 0.05, vs N: p less than 0.005, vs HT) and 2.71 +/- 0.30 in WHO II with AP (p less than 0.02, vs N: p less than 0.001, vs HT). Ejection time index (ETI) was 385 +/- 15 msec in N, 399 +/- 16 in AP (p less than 0.05, vs N), 387 +/- 13 in WHO I, 385 +/- 15 in WHO II, 363 +/- 25 in WHO III (p less than 0.05, vs N), 393 +/- 16 in WHO I with AP and 402 +/- 15 in WHO II with AP (p less than 0.05, vs N: p less than 0.01, vs HT). Pre-ejection period index (PEPI) was 142 +/- 10 msec in N, 135 +/- 11 in AP, 148 +/- 12 in WHO I, 156 +/- 13 in WHO II (p less than 0.005, vs N), 192 +/- 24 in WHO III (p less than 0.001, vs N), 134 +/- 13 in WHO I with AP (p less than 0.05, vs HT) and 136 +/- 9 in WHO II with AP (p less than 0.001, vs HT). These results showed that the ET/PEP ratio in HT with AP was significantly higher than that in HT alone, and this increase in ET/PEP ratio was mainly due to the shortening of PEP interval in WHO stage I and the lengthening of ET in addition to it in WHO stage II.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

[Acinic cell carcinoma of the trachea--a case report].

A 27-year-old woman was admitted to our hospital complaining of dyspnea. Bronchoscopic examination revealed an endotracheal mass in the lower trachea. Endoscopic removal of the lesion was done by the electrocoagulation method followed by wide circumferential excision and reconstruction of the trachea three days later. The patient made an uneventful recovery and has had no recurrence in two years of follow-up. The diagnosis of acinic cell carcinoma was made by light microscopy. This is the first description, to our knowledge, of a primary neoplasma of the intrathoracic trachea having the histological appearance of a salivary gland acinic cell tumor.

Adult↗
PubMed1984

A catheter-induced syncopal attack in a case of hypertrophic obstructive cardiomyopathy.

A 48-year-old man with hypertrophic obstructive cardiomyopathy (HOCM) was studied by serial cardiac catheterization during incidentally induced syncope. His hospital admission was for repeated syncopal attacks and chest pain. His electrocardiogram showed giant negative T waves (greater than 10 mm) in V3, V4 and V5 leads, and his M-mode echocardiogram disclosed typical asymmetric septal hypertrophy, systolic anterior movement of the mitral valve, and a midsystolic semiclosure of the aortic valve. During cardiac catheterization, we incidentally induced syncope and recorded the serial pressure changes. During syncope, systemic blood pressure dropped without appreciable changes in pulmonary arterial and right ventricular pressures. Although blood pressure was maintained by administering etilefrine and hydrocortisone, syncope persisted. After administration of propranolol, he recovered from syncope. He was on sinus rhythm throughout the examinations. The ejection time (ET) obtained from the aortic pressure curve was extremely short (160 msec) during syncope and prolonged (300 msec) after recovery without significant change in the heart rate. We believe that the prompt intravenous administration of propranolol was very effective in relieving myocardial spasm as a possible cause of syncope.

Cardiac Catheterization↗