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Biomedical subjects

Y Hirose

Publications and source records attributed to Y Hirose.

At least 235 records · Page 13Linked to original sources

The distribution of tissue insulin receptors in the mouse by whole-body autoradiography.

The distribution of insulin binding sites in the mouse was investigated by in vivo whole-body autoradiography. Male mice were injected intravenously with 125I-insulin in the absence of and, in the presence of, excess unlabeled insulin. Three, 6, 15, 30 and 60 minutes after injection, the animals were perfused and subjected to autoradiographic procedures. Specific insulin binding was observed in the choroid plexus, liver, gastrointestinal tract, spleen, pancreas, deferent duct, and Harderian gland. In the liver and spleen, the distribution of binding sites was heterogeneous. In the liver, the density of the binding was higher around the branches of the portal vein than around the central vein. In the spleen, the marginal zone exhibited a higher density than the white and red pulp. The kidney cortex, and the thyroid gland showed a high degree of insulin binding, but the binding was nonspecific. The binding of insulin to other tissues and organs, including the skeletal muscle and fat, was weak, and most of the binding was nonspecific.

Animals↗

[Clinical significance of carotid and ocular bruits in cerebrovascular disease].

We investigated the clinical significance of carotid and ocular bruits in 250 consecutive patients with cerebrovascular disease (CVD). The incidence of bruits was compared with that in 100 age- and sex-matched neurological controls without CVD. In the cerebrovascular disease group, carotid bruits alone were found in 12 patients, both carotid and ocular bruits in 7, and ocular bruits alone in 2. Carotid bruits were found only in 3 controls. We then evaluated cerebrovascular disease in the 25 patients (16 men and 9 women) who had bruits. The patients ranged from 55 to 81 years in age (mean: 70.6 years). The patients with carotid bruits alone constituted the largest group, and those with ocular bruits alone were the smallest group. Carotid bruits were heard and abnormal blood flow was observed in 19/28 arteries of the 21 patients who underwent echo-flow studies. Carotid artery stenosis/occlusion was detected in 24/31 arteries (77%) in 23 patients who underwent digital subtraction angiography (DSA). Thus, the sensitivity was 0.77 and specificity of a carotid bruit 0.91, respectively. In 9/10 patients with unilateral ocular bruits, ipsilateral or contralateral carotid artery stenosis/occlusion was detected. Diminished cerebral blood flow was observed in 10/15 patients with bruits who underwent SPECT. Of these 8 had reduced cerebral blood flow ipsilaterally to the bruit. Blood flow was reduced in the carotid artery territory in all of the patients, and watershed reductions were commonest. Among the 25 patients, some showed neurological semiology of the vertebrobasilar territory in addition to that of the carotid territory.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Malignant lymphoma developing from the wall of chronic empyema following artificial pneumothorax].

A 60-year-old man who had had chronic empyema following an artificial pneumothorax for pulmonary tuberculosis when he was 26 years old developed malignant lymphoma of the chest wall. The patient was admitted because of right pyothorax as a result of pseudomonas aeruginosa infection and underwent right thoracotomy. During lavage of the right thoracic cavity a tumor was found arising from the empyematic wall. Pathologic examination revealed that it was malignant lymphoma (diffuse large, immunoblastic, B cell type). Treatment with VEAP-Bleomycin elicited a good response. Seven months after chemotherapy, the patient underwent thoracoplasty in addition to packing the cavity with the latissimus dorsi and the greater omentum. Following this, the patient received chemotherapy once a month for one and a half years, after which he was kept under close observation without treatment. Complete remission has now lasted for 49 months since the initial treatment. This is the first reported lymphoma case with closure of the empyematic wall and is remarkable since this patient has remained in complete remission for the last two years without any treatment.

Empyema, Pleural↗

Microtubule organization in lymphoid malignancies.

The abnormal organization of actin-containing microfilaments and vimentin-containing intermediate filaments in neoplastic lymphocytes of T and B cell origin has been described. We investigated microtubules of pathologic cells from 34 lymphoid malignancies, by immunofluorescence microscopy, using monoclonal tubulin antibody. In most cases, apart from two cases of lymphoma, one T cell lymphoma and one B cell lymphoma, interphase leukemia cells, lymphoma cells, and myeloma cells were shown to contain well-organized microtubules which were associated with a microtubule organization center at one end. In the cells of a patient with T cell lymphoma, although microtubules were not visible in the lymphoma cells from lymph nodes, they became visible after 72 hours in culture with concanavalin A (Con A) and interferon alpha. Cap formation was observed with antitubulin monoclonal antibody in the peripheral blood lymphocytes from a chronic lymphocytic leukemia patient, but well-developed microtubules were observed on other occasions in the same patient. There were no obvious structural differences between microtubules in T and B cell lymphoid malignancies, but leukemia cells and lymphoma cells with irregularly shaped nuclei, such as adult T cell leukemia cells and B cell lymphoma cells with cleaved nuclei, had complicated microtubules surrounding their irregular nuclei. In general, after blastogenic stimuli with phytohemagglutinin-P (PHA-P), Con A, and pokeweed mitogen (PWM), the development of the microtubules was proportional to the incorporation of 3H thymidine (3H-TDR). In most cases, after incubation with granulocyte colony-stimulating factor (G-CSF) and interferon alpha, the number of intact cells decreased and the number of degenerated cells increased, but the intact cells had intact microtubules.

Adolescent↗

Microvessel and astroglial cell densities in the mouse hippocampus.

In order to study the factors responsible for glucose uptake in the mouse hippocampus, microvessel and astroglial cell densities were measured and compared in each laminal region. Microvessel density was examined on histologically prepared sections after injection of Indian ink and measured by means of an image analyser. Astroglial cell density was determined after the cells were stained immunohistochemically. Microvessel and astroglial cell densities were determined in 10 different hippocampal structures. Microvessel and astroglial cell densities were strongly correlated in all layers except the pyramidal cell layers. The highest density of perfused microvessels was found in the stratum lacunosum-moleculare, compared with other regions, and the lowest values were found in the stratum lucidum and dentate granular cell layer. Among pyramidal cell layers, microvessel density in sector CA3a was significantly higher than that in CA1.

Animals↗

[Influence of hypertensive left ventricular hypertrophy on detection of ischemic area with exercise thallium-201 myocardial scintigraphy].

Sixty-four patients with single left anterior descending artery disease having effort angina (group A: 40 patients without hypertension, group B: 10 patients with hypertrophic hypertension, group C: 14 patients with non-hypertrophic hypertension) were assessed the influence of hypertensive left ventricular (LV) hypertrophy on detection of ischemic area. The criterion of hypertrophy by two-dimensional echocardiography was > 12 mm in the wall thickness of interventricular septal or posterior wall. Population in Group B might show low detectability in ischemic area by 201Tl myocardial scintigraphy (positive thallium rate 60%, defect score 2.7 +/- 3.6), and high lung thallium uptake and high frequence of ECG positive among three groups. In semiquantitative analysis, the washout rate of the posterolateral wall and %RD (delayed %uptake-initial %uptake) of the septal wall in patients with Group B were lowest among three groups. However, the washout rate in the septal wall against the posterior wall, and the initial %uptake and the delayed %uptake of the septal wall were not significantly different among three groups. We could conclude that the decreased washout rate in nonischemic area with hypertensive LV hypertrophy might make the ischemic area masked.

Aged↗

[The efficacy of blood conservation technique for coronary artery bypass graft surgery].

To evaluate the efficacy of blood conservation technique at our center, 144 patients undergoing primary coronary artery bypass grafting were studied between Jan. 1988, and Dec. 1990. Combined intraoperative and postoperative autotransfusion technique reduced the requirement of homologous blood to a half and 24% of the patients were without homologous transfusion. With more use of dilutional autotransfusion, 41% of the patients were without homologous transfusion. Intraoperative and postoperative autotransfusion technique is effective and dilutional autotransfusion is also a relatively effective method to reduce homologous transfusion.

Aged↗

[Thallium-201 scintigraphy after dipyridamole infusion in patients with ischemic heart disease--comparison with maximal exercise].

Myocardial images after dipyridamole infusion (DIP-Tl) were compared with maximal thallium-201 images (Ex-Tl) to determine the utility for detecting coronary artery disease and the ischemic level in ischemic regions. Ex-Tl was performed in 36 patients of angina pectoris (Group 1), and DIP-Tl was performed in 22 patients of angina pectoris (Group 2), who were divided into two groups (Group 2a: 15 patients with low level exercise, Group 2b: 7 patients without low level exercise). Each group had normal controls (41, 27 and 31 people). The detectability of coronary artery by DIP-Tl was almost same with Ex-Tl (sensitivity 85% vs. 86%, specificity 80% vs. 95%). In the case of normal controls, the mean washout rate of group 2b was 44.4%, which was less than other two groups (50.6% for group 1, 48.8% for group 2a). And the mean myocardial/background (M/B) ratio of group 2b was 4.3 less than other two groups (4.7 for group 1, 4.9 for group 2a). In the case of the patients of angina pectoris, washout rate, M/B ratio, initial % uptake and delayed % uptake in the ischemic region were almost same among the 3 groups. This study demonstrates that DIP-Tl is as effective as Ex-Tl, and the ischemic level in the ischemic region is almost same among the 3 groups. But the thallium accumulation in the background of the group 2b is slightly higher than other two groups in the normal controls, so it is suggested that the image after only dipyridamole infusion becomes slightly unclear.

Coronary Disease↗

[Usefulness of 201Tl myocardial scintigraphy after dipyridamole infusion in patients with atherosclerotic vascular disease].

To determine the utility for detecting ischemic heart disease (IHD), Dipyridamole thallium myocardial images (DIP-Tl) have been performed in the 103 patients with atherosclerotic vascular disease who can't exercise fully. Of 103 patients, there were 36 patients with arteriosclerosis obliterans (ASO), 31 patients with aneurysm of the abdominal aorta (AAA), 24 patients with aneurysm of the thoracic aorta (TAA) and 12 patients with dissecting aortic aneurysm (DAA). Clinical evidence of IHD was found in 20 patients with ASO, 10 with AAA, 7 with TAA and 4 with DAA respectively. Positive evidence of DIP-Tl was identified in 66% of 41 patients who had clinical evidence of IHD, and particularly in the patients with AAA (80%) and ASO (65%). On the other hand, in the patients without clinical evidence of IHD, positive evidence of DIP-Tl was identified in 19% of 62 patients and particularly in the patients with AAA (39%). In all patients, the percentage of the positive DIP-Tl ratio was 38%. And, when the 38% patients of the positive DIP-Tl were added to the patients of the negative DIP-Tl who had clinical evidence of IHD, almost half patients (51%) were considered to be complicated with IHD. This study suggests that the atherosclerotic vascular disease is highly complicated with IHD and DIP-Tl is useful to detect IHD.

Aged↗

[Studies on magnetic resonance imaging of pancreatic cancer].

Diagnostic ability of Magnetic Resonance Imaging (MRI) was evaluated in 41 patients with pancreatic cancer who underwent surgery 1 to 43 days following MRI. MRI of surgical specimens revealed that pancreatic cancer and caudal pancreatitis showed similar intensities when compared with the normal pancreas. The usefulness of the contrast medium, Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA), was confirmed in the differentiation between cancer and caudal pancreatitis. In the diagnosis of tumor extension, portal vein invasion was better diagnosed by MRI than by angiography. (Spearman's rank correlation test showed higher correlation in MRI than in angiography, p = 0.501, 0.464, respectively.) In the diagnosis of the invasion to the anterior pancreatic capsule its sensitivity was 43%, specificity 81% and efficiency 59%. Retropancreatic invasion was diagnosed with a sensitivity of 48%, a specificity of 90% and an efficiency of 59%. Lymph-node metastasis was well demonstrated especially near the pancreas but beyond them it was difficult. The liver metastasis was correctly diagnosed in 7 of 9 cases and was confirmed by laparotomy.

Contrast Media↗

Development of monoclonal antibodies reactive with methamphetamine raised against a new antigen.

Monoclonal antibodies (McAbs) specific to methamphetamine (MA) were produced using p-amino MA coupled to bovine serum albumin (BSA) with glutaraldehyde (GA) as an immunogen and with conventional hybridoma techniques. Hybridoma clones secreting the McAbs were selected by an enzyme-linked immunosorbent assay (ELISA) system using both the above conjugate and BSA modified with GA as screening antigens. In the ELISA system were used avidin and biotinyl-alkaline phosphatase which converts nicotinamide adenine dinucleotide phosphate (NADP) into NAD. The final enzyme activity was determined using diformazan of nitroblue tetrazolium formed together with the NAD produced, alcohol dehydrogenase and phenazine methosulfate. The McAbs from 9 clones were characterized by a crossreactivity test using the ELISA. The McAbs recognized MA (100%), methoxyphenamine (8.0%), ephedrine (2.3%), but did not react with metylephedrine, amphetamine, OH-amphetamine, dimethylamphetamine, beta-phenylethylamine, norephedrine, phentermine and ranitidine. An inhibition curve for MA was obtained in the range of 0.75 to 50 ng.

Animals↗

Enzyme histochemical, immuno histochemical and electron microscopic studies of two cases of leukemic malignant histiocytosis.

Two cases of leukemic malignant histiocytosis had similar morphologic and enzyme histochemical findings. Large blasts with low nuclear/cytoplasmic ratios, occasional azurophilic granules, and immature nuclei with nucleoli were seen in peripheral blood and bone marrow smears. Case 1 had occasional erythrophagocytosis, while in Case 2 it was rare. They were peroxidase negative, and very strongly positive by alpha-naphthyl butyrate esterase stain, the latter being inhibited by sodium fluoride. Acid phosphatase stains were also very strongly positive and were inhibited with tartaric acid. They were also stained granularly with PAS. Surface marker analysis revealed myeloid surface antigens, CD11+, CD13+ and HLA-DR+ in Case 1, and CD11+, CD13+, CD33+ and HLA-DR+ in Case 2. Immunoperoxidase stains of bone marrow biopsies revealed that lysozyme was positive in both cases. S-100 protein was strongly positive in Case 1, but weakly so in the skin tumor and negative in the bone marrow of Case 2. Electron microscopy showed both cases to be myeloperoxidase negative and rich in cytoplasmic organelles, such as lysosomes, mitochondria, and endoplasmic reticuli. Nuclei were irregularly shaped and nucleoli were present in virtually all the cells. These findings suggest that the malignant histiocytes in these two cases derive from bone marrow macrophages, and S-100 protein can also be detected in monocyte-macrophage derived histiocytes.

Adenocarcinoma↗

[Effect of intensive vacuum cleaning in reducing house dust mite antigen in bed rooms of asthmatic children].

House dust mite (Dermatophagoides farinae) antigen was measured by enzyme-linked immunosorbent assay in house dust samples obtained from the bed rooms of asthmatic children and normal controls. In 37 rooms where regular vacuum cleaning was performed, the mean of D.f. antigen was 4.42 +/- 7.55 micrograms/m2. In the 24 bed rooms of asthmatic children, mean levels of D.f. antigen decreased significantly (p less than 0.05) after intensive cleaning (systematic cleaning) was continued for 4 weeks (0.78 +/- 0.93 micrograms/m2) compared to prior to initiation of systematic cleaning (4.12 +/- 6.31 micrograms/m2). Symptom scores decreased in 65% of the asthmatic children. In 8 bed rooms of normal controls, mean levels of D.f. antigen also showed a decrease after systematic cleaning (0.43 +/- 0.62 micrograms/m2) compared to before (5.59 +/- 12.46 micrograms/m2). However there was no significant difference in D.f. antigen between the bed rooms of asthmatic children and normal controls. Intensive cleaning markedly decreased the allergen in both groups, clearly suggesting effectiveness in the reduction of asthmatic attacks in patients and perhaps also in preventing sensitization of healthy children.

Animals↗

[Intramedullary high intensity lesion on T2-weighted MR images in compressive cervical myelopathy].

Magnetic resonance (MR) imaging was performed in 147 patients with compressive lesion of the cervical spinal canal. Intramedullary high intensity lesions were observed on T2-weighted or proton density spin-echo images in patients with cervical spondylotic myelopathy (20.0%) and ossification of the posterior longitudinal ligament of the cervical spine (25.7%), while such signal abnormality was not found in patients with cervical spondylotic radiculopathy. Frequency of this finding was proportional to clinical severity of myelopathy and degree of spinal cord compression. The pathophysiological basis of such signal abnormality was presumed to vary from acute edema to chronic myelomalacia. In most cases showing intramedullary high intensity lesion, the spinal cord was compressed at multiple levels, but the high intensity was usually found at a single level where the compression was maximum. There was a good correlation between the neurological level and the high intensity level on MR images. Thus the intramedullary lesion on MR images is considered to be the main site of lesion responsible for the neurological symptom.

Adult↗

[Is ventilatory anaerobic threshold useful for preoperative assessment?].

The anaerobic threshold (VAT), obtained by measurement of ventilatory volume and by expiratory gas analysis, and the anaerobic threshold (LAT), obtained directly from the lactic acid value in the blood, were compared and evaluated during exercise load in 25 patients with mitral valve disease. Exercise loading was performed with an ergometer using a multistep method of increases of 5 W (Group A, 11 cases) or 10 W (Group B, 14 cases) per minute. The oxygen uptake value at the points of 0.5 mmol.l-1 and 1.0 mmol.l-1 increase in the lactic acid values when compared with the starting values were designated as 0.5 LAT and 1.0 LAT. VAT was found in 4 of 11 (36%) patients in Group A and in 12 of 14 (86%) patients in Group B and the ratio obtained was significantly higher in Group B than in A. The 0.5 LAT values for Group A and B were 2.4 +/- 0.5 and 2.2 +/- 0.3, respectively. The 1.0 LAT values were 2.9 +/- 0.7 and 2.7 +/- 0.4, and among the two groups no significant difference was found concerning 0.5 LAT or 1.0 LAT. VAT was seen in 16 or 25 patients and the average VAT value of the 16 was roughly at the midpoint between the average values for 0.5 LAT and 1.0 LAT. Therefore in patients in which VAT was seen with the expiratory gas method, VAT and LAT values were basically equivalent. However, in Group A, VAT was seen in only 4 of 11 patients and it is a fact that it is difficult to find VAT without a suitable exercise load.

Anaerobic Threshold↗

[The relationship between ventilatory lung motion and pulmonary perfusion shown by ventilatory lung motion imaging].

Using ventilatory lung motion imaging, which was obtained from two perfusion lung scintigrams with 99mTc-macroaggregated albumin taken in maximal inspiration and maximal expiration, the lung motion [E-I)/I) of the each unilateral lung was studied in various cardiopulmonary diseases. The sum of (E-I)/I(+) of the unilateral lung showed a decrease in the diseased lung of localized pleuropulmonary diseases, including primary lung cancer and pleural thickening, and in both lungs in cases of heart diseases, diffuse pulmonary diseases including diffuse interstitial pneumonia and diffuse panbronchiolitis. The sum of (E-I)/I(+) of the both lungs, which correlated with vital capacity and PaO2, showed a decrease in diffuse interstitial pneumonia, pulmonary emphysema, diffuse panbronchiolitis, primary lung cancer, pleural diseases and so on. (E-I)/I(+), correlated with pulmonary perfusion (n = 49, r = 0.51, p less than 0.001), but not a few cases showed mismatch, which was observed in primary lung cancer, pleural diseases, pulmonary emphysema, diffuse panbronchiolitis and so on. (E-I)/I(+) better correlated with pulmonary ventilation by ventilation scintigraphy with 81mKr or 133Xe (n = 49, r = 0.61, p less than 0.001) than pulmonary perfusion. The ventilatory lung motion imaging, which demonstrates the motion of the intra-pulmonary areas and lung edges, appears useful for estimating pulmonary ventilation of the perfused area as well as pulmonary perfusion.

Heart Diseases↗

Intracellular response properties of neurons in the spinal trigeminal nucleus to peripheral and cortical stimulation in the cat.

The responses of the secondary neurons in the spinal trigeminal nucleus oralis (STNo) were recorded intracellularly to peripheral and cortical stimulation in chloralose-anesthetized cats. Electrical stimulation of the trigeminal sensory nerves (the frontal, infraorbital and inferior alveolar nerves) evoked an EPSP superimposed by one or a few spikes followed by a biphasic IPSP in one group of STNo neurons (Type I), and a prolonged EPSP superimposed by a burst of spikes in the other group of STNo neurons (Type II). Nearly half of Type I neurons were trigeminothalamic neurons projecting to the contralateral ventral posteromedial nucleus, while the remaining Type I and all the Type II neurons were non-projection neurons. A majority of Type I neurons responded with spike potentials to stimulation of only one sensory nerve, while most Type II neurons responded to stimulation of more than one nerve. Stimulation of the contralateral primary somatosensory cortex evoked IPSPs in most Type I projection neurons, and EPSPs in all Type II as well as most Type I non-projection neurons. In Type I neurons touch or pressure applied to a circumscribed area in the facial skin evoked an EPSP superimposed by one or a few spikes followed by a biphasic IPSP, and IPSPs were evoked from a wide surrounding area in the face by the same mechanical stimulation. In Type II neurons innocuous mechanical stimulation within a wide area evoked an EPSP, while IPSPs could not be induced from anywhere. The results indicate that postsynaptic inhibition is involved in the surround inhibition as well as corticofugal descending inhibition of sensory transmission in the trigeminal sensory nucleus.

Action Potentials↗