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Biomedical subjects

M Usui

Publications and source records attributed to M Usui.

At least 217 records · Page 12Linked to original sources

Autonomic nervous system activity in idiopathic dilated cardiomyopathy and in hypertrophic cardiomyopathy.

To assess autonomic nervous activity in patients with cardiomyopathies, analysis of heart rate variability was performed using 24-hour ambulatory electrocardiograms in 14 patients with idiopathic dilated cardiomyopathy (IDC), 15 with hypertrophic cardiomyopathy (HC) and 18 healthy subjects. Heart rate variability during the night and daytime was calculated using fast-Fourier transform, and power spectra were quantified in 2 frequency bandwidths: 0.00 to 0.15 Hz (low-frequency power [LF]) and 0.15 to 0.50 Hz (high-frequency power [HF]). Log(HF) was used as an index of parasympathetic nervous activity, and log(LF/HF), of sympathetic nervous activity. Log(HF) was significantly lower and log(LF/HF) was significantly higher in IDC. These changes were related to ejection fraction. In HC, lower log(HF) and higher log(LF/HF) were recognized only during the night, and these changes were independent of the degree of myocardial hypertrophy. Our results indicated attenuation of parasympathetic activity and enhanced sympathetic activity in HC during the night, and also in IDC. Assessment of autonomic imbalance by analysis of heart rate variability may be useful for understanding the pathophysiology of cardiomyopathies.

Autonomic Nervous System↗

Horizontal component of electro-oculogram as a parameter of arousal in dementia: relationship between intellectual improvement and increasing arousal under pharmacotherapy.

Although nootropics and metabolically active compounds sometimes attenuate intellectual deficits of dementia patients, this mechanism has not been discussed or investigated. The authors hypothesized that these compounds act to enhance attention and/or concentration by increasing the arousal level, and then improve intellectual functions. Based on this hypothesis, the authors investigated the arousal level and the improvement of intellectual functions in ten patients with Alzheimer type dementia and ten patients with multi-infarct dementia before and after 3 months pharmacotherapy using bifemelane hydrochloride. They then analyzed whether the increases in arousal level involves or relates to the improvement of intellectual functions. On the 20 patients, psychological tests were carried out, and the arousal level was evaluated using the frequency of rapid eye movements in the electro-oculogram (EOG) before and after 3 months administration of bifemelane hydrochloride. As a result, a significant positive correlation was observed between the improvement on the Hasegawa's dementia scale and the rate of increase in rapid eye movements in the EOG. The EOG monitoring can be a great help in establishing an objective evaluation method on drug efficacy.

Aged↗

Epitopes on Cry j I and Cry j II for the human IgE antibodies cross-reactive between Cupressus sempervirens and Cryptomeria japonica pollen.

Forty sea from French patients allergic to Cupressus sempervirens pollen were tested for cross-reactivities against Cry j I, Cry j II (major allergens of Cryptomeria japonica pollen) and other pollen allergens from botanically related plants. Seventy-three per cent of the sera reacted with either Cry j I or Cry j II, or with both of them. These IgE cross-reactions were blocked effectively by mAb 046 (anti-Cry j I) or N26, T27 (anti-Cry j II), and weakly by mAbs 052, 027 and 026 (anti-Cry j I). Furthermore, the IgE antibodies in two sera, #40 and #11, bound to peptide fractions obtained from enzyme-digested Cry j I, and mAb 027 could also bind to the fractions. Analyses of the amino acid sequences of the peptides revealed that reactive peptides contained "NGNATPQLTKNAGVLTCSLSKR" sequence and the third residue N3 was glycosylated, however, when the N3 was not glycosylated, the IgE antibodies did not react, but mAb 027 could. The glycosylation of the N3 might be required for IgE-binding to the peptides. Sugar component on the N3 residue was found to be 0.4 mol galactose, 1.3 mol mannose, 0.8 mol fucose and 2.0 mol N-acetyl-glucosamine. Cross-reactivities against other pollen allergens from botanically related plants were found in most of the sera. However, many of these reactivities were detected by sandwich ELISA but not by an ELISA using allergen-coated plates, indicating that it is important to select an appropriate ELISA procedure in order to detect an allergen or an IgE antibody to an allergen.

Allergens↗

Hypothenar hammer syndrome in workers occupationally exposed to vibrating tools.

Among 330 vibration-exposed workers, 24 cases of hypothenar hammer syndrome in 29 hands were diagnosed by arteriography. The right hand was involved in 13, the left hand in six, and both hands in five cases. The mean age was 55 years, mean duration of vibration exposure 19.4 years, and mean duration of episodic Raynaud's phenomenon 6.4 years. The vascular lesions of the ulnar arteries were classified into three major types with subtypes. Type 1: stenosis of the superficial palmar arch around the hook of the hamate. Type 2a: occlusion of the superficial palmar arch around the hook of the hamate. Type 2b: occlusion of both superficial and deep palmar arches around the hook of the hamate. Type 3a: occlusion of the ulnar artery at the proximal part of the wrist. Type 3b: occlusion of the ulnar artery near the wrist with the occlusion of the dorsal carpal branch of the ulnar artery.

Adult↗

Parasympathetic activity is a major modulator of the circadian variability of heart rate in healthy subjects and in patients with coronary artery disease or diabetes mellitus.

Autonomic heart rate control was assessed by power spectral analysis of heart rate variability in 24-hour ambulatory electrocardiographic recordings from 23 healthy subjects, 14 patients with coronary artery disease without cardiac dysfunction, and 14 patients with diabetes mellitus. The log value of the ratio of the low-frequency component (LF = 0.04 to 0.15 Hz) to the high-frequency component (HF = 0.15 to 0.5 Hz) and logHF were employed as indexes of sympathetic and parasympathetic activity, respectively. Diurnal and nocturnal logLF, logHF, and log(LF/HF) values were calculated for heart rates of 60, 70, and 80 beats/min. Intergroup differences among these three variables were not significant at any heart rate. Although a heart rate-related decrease in logHF was generally observed, the relationship between log(LF/HF) and heart rate was not consistent. The correlation between diurnal and nocturnal logHF values was significant at all three heart rates (r = 0.63, 0.87, and 0.59), whereas the diurnal log(LF/HF) was correlated with the nocturnal value only at 70 beats/min (r = 0.77). These results suggest that the heart rate during normal daily activities is a reliable indicator of parasympathetic tone, if not sympathetic tone, in healthy subjects and patients with coronary artery disease or diabetes mellitus.

Aged↗

Relationship between distribution of hypertrophy and electrocardiographic changes in hypertrophic cardiomyopathy.

To assess the relationship between the distribution of hypertrophy and electrocardiographic changes in patients with hypertrophic cardiomyopathy, magnetic resonance imaging and ECG findings were correlated in 25 patients with apical hypertrophy (group I), 15 patients with both apical and basal hypertrophy (group II), and 11 patients with hypertrophy localized to the basal left ventricle (group III). The number of precordial leads with negative T waves (-0.5 mV or more) was greater in group I than in groups II and III (I = 3.0 +/- 1.5, II = 1.7 +/- 1.5, III = 0.3 +/- 0.6; p < 0.01). Giant negative T waves (-1.0 mV or more) in precordial leads were found in 13 patients (52%) in group I and five patients (33%) in group II but were not found in group III. In contrast, tall positive T waves (> or = 1.0 mV) in precordial leads were found in two patients (13%) in group II and five (45%) in group III but were not found in group I. These results suggest that the distribution of hypertrophy in patients with hypertrophic cardiomyopathy produces a particular T wave polarity in precordial leads.

Adult↗

Microsurgical reconstruction in limb-salvage procedures: comparison between primary and secondary reconstruction.

Limb-salvaging procedures after malignant tumor resection in the extremities were performed in 22 cases, utilizing microsurgical tissue transplantation. Five patients had soft-tissue tumors and 17 had bone tumors. Thirteen cases were primarily and nine were secondarily reconstructed. The advantages and disadvantages of both primary and secondary reconstructions were compared: as to technical difficulty, primary reconstruction was much easier. Chemotherapy was necessary just before and/or after reconstruction in eight of 13 cases of primary reconstruction. Delayed union or non-union occurred more frequently in patients who required chemotherapy, but eventual union was achieved in all cases by adding a conventional bone graft. As for oncologic and functional status, there was no difference in oncological status between the primary and secondary groups, but the primary reconstructions showed better functional results. Although individualized treatment is of utmost importance when utilizing microsurgical reconstruction to save limbs, primary reconstruction can be done most successfully when there is a wide surgical margin after tumor resection and when attention is paid to the avoidance of such complications as delayed union or non-union.

Adolescent↗

Responders and non-responders to bifemelane hydrochloride in Alzheimer-type and multi-infarct dementia.

Although metabolically active compounds sometime attenuate cognitive deficits of dementia patients, this mechanism has not been discussed or investigated. We hypothesized that these compounds improve cognitive disorders not by directly acting on this cognitive function, but by increasing the arousal level. Based on this hypothesis, we investigated the change of arousal levels and the improvement of intellectual functions in 10 patients with Alzheimer-type dementia (ATD) and 10 patients with multi-infarct dementia (MID) before and 3 months after pharmacotherapy using bifemelane hydrochloride. For each patient, a psychological test battery was carried out and the arousal level was evaluated using the frequency of rapid eye movements in the electro-oculogram (EOG) and the frequency analysis of electroencephalogram (EEG) before and after the treatment. Evaluation of the cognitive improvement was made and eight out of the 20 patients were regarded as responders to the treatment. The frequency of small rapid eye movements (SREM) in the EOG increased significantly only in responders and the rate of change in SREM appearance in responders was significantly different from that in non-responders. This finding suggests that a part of the intellectual improvement in ATD and MID results from the increased level of arousal.

Aged↗

Antifibrillatory effects of class III antiarrhythmic drugs: comparative study with flecainide.

The antifibrillatory effects of flecainide 1 mg/kg + 0.05 mg/kg/min intravenously (i.v.), bretylium 6 mg/kg i.v., D-sotalol 2 mg/kg + 0.1 mg/kg/min i.v., and E-4031, a new class III drug, 50 micrograms/kg + 5 micrograms/kg/min i.v. were compared with three different methods of determining ventricular fibrillation threshold (VFT) in anesthetized open-chest dogs. In protocol 1, VFT was determined with 2-S, 50-Hz continuous pulses. Flecainide (n = 7) prolonged intraventricular conduction time (CT) and ventricular effective refractory period (ERP) and increased VFT significantly. Bretylium (n = 6) prolonged ERP slightly, but did not increase VFT significantly. Both D-sotalol (n = 6) and E-4031 (n = 6) prolonged ERP and increased VFT. In protocol 2, VFT was determined with the extrastimulus technique in dogs, with localized ventricular necrosis produced with protease. Flecainide (n = 10), D-sotalol (n = 8), and E-4031 (n = 8) restored VFT, which had been decreased by protease injection, to the baseline level, whereas bretylium (n = 8) did not. In protocol 3, the train pulse method with 100-Hz train pulses covering the vulnerable period was used in the same dogs used for protocol 2. Flecainide, bretylium, and D-sotalol increased VFT, but E-4031 did not. The antifibrillatory effects of class III drugs differ depending on the method of VFT determination. The present data suggest that the antifibrillatory effects of antiarrhythmic drugs should be assessed by different methods of VFT determination.

Analysis of Variance↗

Suppression of murine IgE responses with ovalbumin-pullulan conjugates: comparison of the suppressive effect of different conjugation methods and different molecular weights of pullulan.

Ovalbumin (OVA)-pullulan conjugates were made using four different conjugation methods and eight different molecular weights of pullulan ranging from 4,200 to 600,000. Pretreatment of mice by the administration of conjugates made by using cyanulic chloride or cyanogen bromide and pullulan of molecular weight 40,000 or more, anti-OVA IgE antibody response was suppressed completely and anti-OVA IgM and IgG antibody response was enhanced. In contrast, by the administration of conjugates made by using an oxidation or thiol activation method, only partial suppression of anti-OVA IgE antibody response was achieved and no enhancement of anti-OVA IgM and IgG antibody production was observed.

Animals↗

Dandy-Walker syndrome forming a giant occipital meningocele--case report.

A boy was born with Dandy-Walker syndrome associated with a giant occipital meningocele, cleft lip, and cleft palate. The meningocele was actually a component of the giant posterior fossa cyst which communicated with the fourth ventricle. A cyst-peritoneal shunt achieved a considerable decrease in the size of the meningocele, but decubital ulcers developed due to restricted head movement caused by the occipital lesion. Cranioplasty removed a wide area of the inferior occipital bone, and the boundary between the superior occipital and parietal bones was thinned to allow free bending of the bone flap. The meningocele was removed totally in the third operation, but infection of the wound and pneumonia developed, causing death. The coexistence of Dandy-Walker syndrome and occipital meningocele, together with midline facial anomalies, may suggest a later pathogenesis of Dandy-Walker syndrome than previously believed.

Cerebrospinal Fluid↗

[Immunological and physicochemical properties of Cry j II, the second major allergen of Japanese cedar pollen (Cryptomeria japonica)].

Cry j II, the second major allergen of Japanese cedar (sugi, Cryptomeria japonica) pollen was examined for the allergenicity by intradermal test and RAST. Nineteen of the 25 allergic patients examined, showed positive reaction to the Cry j II. Contents of Cry j II in the extracts of the pollen collected in various regions from 1977 to 1991 showed yearly variation ranging from 2.9 to 14 mg/100 g pollen, whereas the amount of Cry j I in the extract was comparatively stable at about 35 mg/100 g pollen. Physicochemical treatments of Cry j I and Cry j II suggested that specific human IgE antibodies and some mAbs bind to conformational epitopes which are denatured and destroyed by certain treatments.

Allergens↗

[A case of pleomorphic adenocarcinoma of the ciliary body].

We performed local resection of a ciliary body tumor, which was diagnosed as pleomorphic adenocarcinoma arising from nonpigmented epithelium of the ciliary body. The patient was a 57-year-old male, and the tumor was found incidentally at an ophthalmologic examination. Since the possibility of malignant tumor could not be ruled out, local resection of the tumor was performed. The tumor developed from the pars plicata and the size was 5.5 x 6.0 x 7.5 mm. Histologically, the tumor cells displayed heteromorphism and revealed tubular and glandular structures which continued to the ciliary body epithelium. Melanin pigment was not observed, except in one small area of the tumor. The interstitium of the tumor tissue was stained with alcian blue, and a immunohistochemical study showed that tumor cells were positive for epithelial membrane antigen (EMA) and vimentin, but negative for S-100 protein and carcinoembryonic antigen (CEA). Electron microscopy revealed desmosomes between cells, and microvilli were observed at the margin of the glandular cavity structure. In this case, no severe complications occurred even after local resection and good visual function was maintained.

Adenocarcinoma↗

[A case of pulmonary alveolar microlithiasis].

The patient was a 42-year-old man. When he was a third grade pupil of elementary school, he was diagnosed as having miliary tuberculosis. He was absent from school for 2 years for the treatment of the disease. However, miliary tuberculosis did not improve in spite of 2 years of treatment. At that time he was diagnosed as having pulmonary alveolar microlithiasis. He did not receive any treatment for the following 30 years. Recently, he visited our department because of occasional chest pain. The following tests were performed; chest CT, tomography, respiratory function test, RI test (99mTc bone scintigram and 67Ga scintigram) and bronchoscopy. Bronchoalveolar lavage (BAL) was performed of B5b, and transbronchial lung biopsy (TBLB) of left B5b, B8b, B9b and B10b to make the accurate diagnosis of pulmonary alveolar microlithiasis. This case of pulmonary alveolar microlithiasis with a protracted course of 30 years (in which chest X-ray films taken 27 years ago were available) is reported together with a discussion of the literature.

Adult↗

Usefulness of a novel monoclonal antibody against human osteocalcin in immunohistochemical diagnosis.

A novel monoclonal antibody against human osteocalcin, recently established in our laboratory, was shown by immunoblotting and immunohistochemistry to react specifically with human osteoblasts. In the present study, the antibody was applied to the immunohistochemical diagnosis of human bone tumours, especially osteoblastic tumours. The antibody reacted with all 27 osteosarcomas. No positive reaction was found either in chondrosarcoma, giant cell tumours of bone, soft tissue tumours or epithelial tumours. A positive reaction was found preferentially in the cytoplasm of most of the osteosarcoma cells, but not in the extracellular matrix. Since the antibody reacted with formalin-fixed and paraffin-embedded tissues, it will be a useful tool for routine immunohistochemical diagnosis of osteoblastic lesions.

Animals↗