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T Maeda

Publications and source records attributed to T Maeda.

At least 829 records · Page 46Linked to original sources
PubMed1992

Arterial blood ketone body ratio as a possible indicator for predicting fulminant hepatitis in patients with acute hepatitis.

Encephalopathy and severe coagulopathy in patients with acute hepatitis (AH) are good markers for the diagnosis of fulminant hepatitis (FH), which occurs in only about 1% of AH patients. However, even if patients show severe coagulopathy, it is quite difficult to predict FH before the onset of encephalopathy. The ratio of acetoacetate/beta-hydroxybutyrate in arterial blood (KBR) has been reported to reflect the cellular energy charge level in hepatocytes. In our previous report, KBR was quite low in FH patients and was an excellent marker for predicting the prognosis. KBR of normal subjects is distributed in a range of 1.0-2.1 (1.54 +/- 0.26, mean +/- SD). In this study, we assessed KBR serially in 15 AH patients with severe coagulopathy (hepaplastin test (HPT) < 40%), including seven patients who developed FH, to see if we could predict FH by using KBR as a marker. Seven patients with KBR < 0.6 of long duration (4 days or more) were complicated with hepatic encephalopathy (HE) and it took 3 or more days of KBR below 0.6 before HE appeared. The other eight patients with KBR < 0.6 of short duration (less than 4 days) were not complicated with HE. These data suggest that AH patients with HPT < 40% and a 3-day duration of KBR < 0.6 are at serious risk of FH.

Acute Disease↗
PubMed1992

Predominant expansion of V gamma 9/V delta 2 T cells in a tularemia patient.

We describe a 58-year-old man with tularemia and expanding gamma delta T cells in his peripheral blood lymphocytes (PBL) (32.7% of total PBL). In the present work, we analyzed the T-cell receptor V gamma/V delta repertoire of these cells by making use of the polymerase chain reaction and flow cytometry and found that they were mostly CD4- CD8- CD3+ V gamma 9/V delta 2+. The sequence analysis of 16 cDNA clones encoding the V gamma 9-J region revealed that the V gamma 9-Jp combination was strikingly overrepresented but that the junctional (N) region was heterogeneous. This suggested that the gamma delta T cells in PBL from a patient with tularemia were polyclonally expanded.

Base Sequence↗
PubMed1992

Changes in the Ki-67 labeling rates of head and neck squamous cell carcinomas during preoperative radiation therapy.

Immunostaining with Ki-67 monoclonal antibody was performed on frozen sections of biopsy specimens obtained before and during preoperative radiation therapy from 21 patients with head and neck squamous cell carcinoma. The Ki-67 labeling rates before radiation therapy and at radiation doses of 10 and 20 Gy ranged from 21 to 71% (mean: 35.0%), from 7 to 49% (mean: 25.8%) and from 1 to 44% (mean: 14.8%), respectively. One of the 2 patients whose tumors showing Ki-67 labeling rates of greater than 48% (mean +1 SD) before radiation therapy suffered local relapse shortly after the treatment. Moreover, tumors with rapidly decreased Ki-67 labeling rates (lower than 3%) at radiation doses of 20 Gy were related to poor clinical outcome: 4 out of 6 patients whose tumors showed Ki-67 labeling rates below 3% (mean -1 SD) at 20 Gy of irradiation had local relapses or showed distant metastases. These findings indicate that immunostaining with Ki-67 monoclonal antibody of biopsy specimens of head and neck squamous cell carcinoma, before and during radiation therapy, is very useful in assessing the clinical outcome of the patients.

Adult↗
PubMed1992

T cell receptor repertoire of infiltrating T cells in lips of Sjögren's syndrome patients.

Infiltrating T cells around salivary glands in the lips of Sjögren's syndrome (SjS) patients are crucial in the pathogenesis of this disease. To analyze the nature of infiltrating T cells, their T cell receptor repertoire was examined with quantitative polymerase chain reaction. The repertoire of V beta transcripts in lips of SjS was not restricted; however, the V beta 2 and V beta 13 genes were predominantly expressed on the T cells of lip specimens in six and four of seven lips, respectively. Predominance of these genes was specific in lips because no predominant V beta transcripts were found in lips from healthy subjects and PBLs from SjS patients. These results indicated that the V beta 2- and V beta 13-positive T cells expanded specifically and preferentially in SjS lips, thereby suggesting the possible role in triggering the autoimmunity of this disease.

Base Sequence↗
PubMed1992

Combined use of silver staining of the retrograde tracer WGAapoHRP-Au and pre-embedding immunocytochemistry for electron microscopy: demonstration of dopaminergic terminals in synaptic contact with striatal neurons projecting to the substantia nigra in the rat.

We investigated the applicability of the pre-embedding immunoperoxidase technique to WGAapoHRP-Au retrograde tracing. After injection of the tracer into the substantia nigra of rat, the brain was fixed and cryostat sections were immunostained for dopamine. The sections were osmicated and silver-stained to amplify the colloidal gold particles. Products of both the immunoperoxidase staining and the silver staining could be detected and distinguished by electron microscopy at low magnification. The ultrastructure was so well preserved that synaptic characteristics could be investigated. Dopaminergic terminals were demonstrated to synapse with striatal neurons projecting to the substantia nigra.

Animals↗
PubMed1992

Fragmentation hemolysis in a patient with hypertrophic obstructive cardiomyopathy and mitral valve prolapse.

We encountered a 65-year-old female with hypertrophic obstructive cardiomyopathy and mitral valve prolapse who had infective endocarditis and hemolytic anemia. The infecting organism of endocarditis was group A streptococci. With regard to the etiology of the hemolytic anemia, fragmentation hemolysis was considered because fragmented red cells and elevated lactic dehydrogenase were observed. Haptoglobin was markedly decreased. Coombs' test, Ham's test and abnormal hemoglobin were negative. She had not had a hemolytic attack in the past. Ultrasonic cardiography showed asymmetrical septal hypertrophy, mitral valve prolapse and 285 mmHg of calculated pressure gradient in the left ventricle. Cardiac catheterization showed 115 mmHg of left intraventricular pressure gradient and mitral regurgitation (grade 2). Hemolysis was slightly improved after treatment with propranolol. Thus, fragmentation of the normal red cells seemed to be due to shear stress.

Aged↗
PubMed1992

Negative washout rate of myocardial thallium-201--a specific marker for high grade coronary artery narrowing.

A decline is usually observed in the myocardial uptake of thallium-201 in delayed imaging compared with initial imaging. In patients with severe coronary artery disease (CAD), the uptake is sometimes higher in the delayed than in the initial imaging, which is expressed as negative washout rate. To evaluate the diagnostic implications of this negative washout rate the findings of dipyridamole thallium scintigraphy in 582 patients with coronary artery disease were evaluated. The negative washout rate was present in 201 of 582 patients (35%). It had a significant association with high grade coronary artery narrowing of > or = 90%. Sensitivity in detecting patients with this high grade narrowing by negative washout rate was 48%, its specificity was 93%, and its positive predictive value was 94%. Sensitivity to detect individual coronary artery narrowing of > or = 90% did not decrease according to the extent of CAD, with the highest detection in the left anterior descending coronary artery and the lowest in the left circumflex coronary artery. Since patients with high grade coronary narrowing often require coronary intervention, the results of this study suggest the diagnostic importance of negative washout rate in the identification of the particular subset of patients with CAD.

Adult↗
PubMed1992

Mexiletine and disopyramide suppress ventricular premature contractions (VPC) irrespective of the relationship between the VPC and the underlying heart rate.

The effects of mexiletine (300 mg/day, 24 patients) and disopyramide (300 mg/day, 20 patients) on ventricular premature contractions (VPCs) were studied using a 24-hour ambulatory electrocardiogram. The VPC frequency was evaluated as a function of the underlying heart rate (HR). The VPC-HR correlation was classified into 2 major types, depending on whether the frequency of the VPC increased with the increased HR (positive type) or not (nonpositive type). The effects of the drugs were assessed based on the VPC-HR correlation and on the percent reduction of the VPC frequency. Mexiletine and disopyramide significantly decreased the frequency of the VPCs of both the positive and nonpositive types. Each drug was assumed to be effective when the percent reduction of the VPC frequency exceeded 70%. Mexiletine (300 mg/day) was 58.5% effective in positive type patients and 33.3% effective in nonpositive type patients, with a total efficacy of 45.8%. Disopyramide was effective in 50% of total cases with 44.4% in positive type patients and 54.5% in nonpositive type patients. However, the efficacy of these drugs on the 2 different types of VPCs was the same statistically. The findings strikingly contrasted those obtained with diltiazem and atenolol, which predominantly suppressed VPCs of the positive type which share similar characteristics with a triggered activity in vitro. We conclude that the mode of action of class I antiarrhythmics on the VPCs differs from that of class II or IV antiarrhythmics, as viewed from the VPC-HR relationship, and that the difference probably comes from the different arrhythmogenesis for positive and nonpositive types of VPCs, in addition to the different electrophysiological actions of mexiletine and disopyramide.

Cardiac Complexes, Premature↗
PubMed1992

Innervation of the periodontal ligament in the dog with special reference to the morphology of Ruffini endings.

The distribution and terminal formation of nerves in the periodontal ligament of dog incisors and canines were investigated by immunohistochemistry for neurofilament protein (NFP) and by electron microscopy. The NFP-immunoreactive nerve fibers were found to be densely distributed in the apical third of the periodontal ligament, while they were sparse in the coronal two thirds. Most of the nerve endings in the periodontal ligament showed a tree-like appearance and resembled those nerve endings demonstrated in the periodontal ligament of human and monkey under the category of free nerve endings. Presumable axon terminals of these were slightly thicker than preterminal portions, running along periodontal collagen fibers and tapering within them. In light microscopic images, at least, they differed from the Ruffini endings which are commonly seen in rodents, displaying a glove-like configuration with extremely expanded tips. Under the electron microscope, however, the tree-like endings of the dog appeared similar to the Ruffini endings of rodents: their terminals were filled with mitochondria, covered with a cytoplasmic process of a Schwann cell, and surrounded by collagen fibers. These ultrastructural findings, combined with the results of previous physiological studies suggest that the nerve endings demonstrated in the present study can be identified as Ruffini endings. It is even stressed that the dog-type of Ruffini ending can be regarded as a representative of the sensory receptors in the mammalian periodontal ligament. In addition to these endings, knobbed endings, corpuscular (lamellated and glomerular) endings, and free nerve endings were rarely encountered in the periodontal ligament of incisors and canines of the dog.

Animals↗
PubMed1992

Histochemical and immunohistochemical demonstration of macrophages and dendritic cells in the lingual periodontal ligament of rat incisors.

The distribution of macrophages in the lingual periodontal ligament of rat incisors was surveyed by histochemical and immunohistochemical methods. Numerous macrophages showing intense ACPase reactions were located primarily in the shear zone of the periodontal ligament. Immunostaining with an ED1-monoclonal antibody that recognizes various subpopulations of macrophages revealed plentiful positive cells showing flamelike profiles throughout the periodontal ligament, in addition to regular macrophages associated with sinusoidal blood vessels. A similar distribution of flamelike cells expressing Ia antigens was demonstrable with immunostaining using an OX6-monoclonal antibody. A consecutive staining of sections for ACPase histochemistry followed by immunoreactions for Ia antigens revealed the presence of two types of the flamelike cells in the periodontal ligament: one with and the other without distinct ACPase activity, corresponding to the macrophage and the dendritic cell, respectively. Either type of flamelike cells was located in the bone-related and shear zones, whereas only dendritic cells without ACPase activity were restricted to the tooth-related zone. OX6-immunonegative cells showing ACPase reactions were also found in the periphery of the sinusoidal blood vessels. Our data are the first to demonstrate the abundance of macrophages and dendritic cells expressing Ia antigens throughout the lingual periodontal ligament of rat incisors. In addition to regular macrophages, an exclusive localization of macrophages with flamelike extensions has been demonstrated in the bone-related and shear zones of the ligament. The region-specific arrangement of macrophages and dendritic cells with various histochemical and immunological features suggests that the periodontal ligament of rat incisor is a useful model for analyzing the process of differentiation of antigen-presenting cells.

Acid Phosphatase↗
PubMed1992

Immunoelectron microscopic observation of calcitonin gene-related peptide (CGRP)-positive nerves in the dental pulp of rat molars.

The ultrastructure of nerves containing immunoreactivity for calcitonin gene-related peptide (CGRP) was investigated in the dental pulp of rat molars. The immunoreactivity was recognized predominantly in unmyelinated nerve fibers, and sparsely in a few myelinated fibers. It was localized throughout the axoplasm, as well as in the large cored vesicles. Small clear vesicles and mitochondria were free of the immunoreaction. The CGRP-immunoreactive nerves were frequently observed to terminate, being devoid of Schwann cell investment, in the vicinity of blood vessels in the coronal pulp, suggesting that CGRP may be involved in the regulation of pulpal blood flow. Moreover, CGRP-immunoreactive axon terminals containing numerous small clear vesicles, a few large cored vesicles and mitochondria were recognized in contact with the cell bodies of odontoblasts and their processes in the dentinal tubules. Although specialized synaptic ultrastructures were not recognizable, a functional association of CGRP nerves and odontoblasts was suggested. Thus, CGRP in the dental pulp appears to have multiple functions, including vascular regulation and sensory transduction.

Animals↗
PubMed1992

Clinical features of 125 patients with sarcoidosis: Okayama University Hospital review of a recent 10-year period.

Clinical features were studied in 125 patients with sarcoidosis (72 females and 53 males) diagnosed at Okayama University Hospital during a recent 10-year period. The age distribution had two peaks in patients in their 20s and the 50s. Over half of the patients were detected at health screening check and were asymptomatic, while the remaining were symptomatic. Twelve patients were in stage 0, 41 were in stage I, 54 were in stage II, 16 were in stage III, and 2 were in stage IV according to the chest x-ray findings. Serum angiotensin converting enzyme levels and serum lysozyme levels were elevated in 60% and 76% of the patients, respectively. The bronchoalveolar lavage fluid showed lymphocytosis, especially of helper T-cells. The clinical features of sarcoidosis appear to depend on the duration of the disease.

Adolescent↗
PubMed1992

Allergic granulomatosis and angiitis with severe cardiac disease: a case in which cardiac function was extremely improved by long-term steroid therapy.

A 38-year-old man with a history of bronchial asthma developed marked eosinophilia, mononeuritis multiplex and transient pulmonary infiltration. Pathological findings from the lung and nerve biopsy were helpful in determining the diagnosis as allergic granulomatosis and angiitis (AGA). Echocardiogram indicated dilation of the left ventricle with impaired systolic contraction. Coronary arteriography demonstrated significant stenosis only in the peripheral segment of the circumflex artery. After 1 year of corticosteroid therapy, echocardiogram revealed improvement of left ventricular contractility evaluated by ejection fraction (from 28% to 67%). To our knowledge, no previous reports have described amelioration of severe cardiac lesions during long-term steroid treatment in patients with AGA.

Adult↗
PubMed1992

Prevention of aortic calcification in patients on hemodialysis by long-term administration of vitamin E.

The effects of vitamin E on the progress of atherosclerosis in patients on hemodialysis was investigated clinically using ACI. There was a significant suppression of the increase in ACI in group A, compared to group B, at the time of observation in each year. On the other hand, no significant changes were noted in BWD, CTR, BP and blood chemical examination, except that the level of MDA was significantly decreased in group A as compared with that in group B 4 years later. Since ACI is an index representing atherosclerosis, the results of this study seemed to suggest that the progress of atherosclerosis was suppressed by long-term administration of vitamin E in patients on hemodialysis.

Aortic Diseases↗
PubMed1992

Mast cell invasion of peripheral nerve in skin lesions of atopic dermatitis.

To ascertain whether or not a spatial relationship between mast cells and peripheral nerves is present in skin lesions of atopic dermatitis, 10 biopsy specimens of the skin lesions were examined with both semi-thin and ultrathin serial sections. Mast cell invasion of peripheral nerves was observed in 9 out of the 10 biopsy specimens (4 subacute lesions, 3 lichenified lesions, and 3 prurigo lesions). The mast cells within peripheral nerves often showed degranulation, and the nerve fiber bundle showed conspicuous edema. The degranulation of mast cells within peripheral nerve bundles and edema of the nerve bundle may pay a role in provoking or aggravating itchiness of atopic dermatitis.

Adolescent↗
PubMed1992

[Serum neuron specific enolase (NSE) levels in patients with non small cell lung cancer].

Serum NSE levels were measured in 126 patients with previously untreated NSCLC. The NSE level was greater than 10 ng/ml in 29 patients (23.0%) and this was considered to be positive. Elevation of serum NSE levels correlated closely with clinical stage except stage I and II. The effect of chemotherapy was evaluated in 74 cases included 22 NSE-positive cases. The response rate was 50% in positive cases and 34.6% in negative cases. However, the median duration of response in positive cases (2.2 months) was significantly shorter than that in negative cases (6.6 months). The median survival time of 6.0 months in positive cases was brief compared with 9.6 months in negative cases. These results indicate that elevation of serum NSE level in patients with NSCLC may be a marker of poor prognosis.

Adenocarcinoma↗
PubMed1992

Immunocytochemical localization of nerve growth factor receptor (NGFR) in human teeth.

The distribution and subcellular localization of nerve growth factor receptor (NGFR) in human teeth has been investigated by immunohistochemistry at the light and electron microscopic levels. Many nerves in the dental pulp were intensely immunoreactive for NGFR. The pattern of distribution was largely similar to that of nerve fibers demonstrated by immunostaining for neurofilament protein (NFP), the most universal marker protein for pulpal nerves. In the predentin and dentin, more nerve fibers were intensely immunoreactive for NGFR than were demonstrable with NFP-antibodies. Immunoelectron microscopy showed that the NGFR-immunoreactivity was localized on the axoplasmic membrane in unmyelinated axons and on the outside of accompanying Schwann cells. No NGFR-immunoreactivity was found on the axons of myelinated nerves nor their supporting cells.

Axons↗