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Biomedical subjects

T Maeda

Publications and source records attributed to T Maeda.

At least 1,099 records · Page 61Linked to original sources
PubMed1987

[Radiotherapy and tumor immunity--analysis using monoclonal antibodies].

In order to better understand the immunologic effects of irradiation, blood levels of lymphocyte subsets were sequentially monitored in 37 patients before and during irradiation treatment for lung cancer. Tumor infiltrating lymphocytes induced by radiotherapy were analysed by the avidin-biotin-horseradish peroxidase method. 49 cases of head and neck cancer were examined. In some cases, remarkable infiltration of lymphocytes was observed surrounding cancer cells during radiotherapy. This infiltration was mainly composed of anti-Leu-3a + 3b positive lymphocytes, and HLA-DR positive cancer cells were remarkably observed.

Antibodies, Monoclonal↗
PubMed1987

Tumorigenicity test of 1,3- and 1,8-dinitropyrene in BALB/c mice.

1,3-Dinitropyrene (DNP) and 1,8-DNP (CAS: 42397-65-9) are very potent mutagens and induce a frameshift-type mutation in the Salmonella test system. Each compound was tested for tumorigenicity in BALB/c mice by sc inoculation of 0.05 mg of the compound once a week for 20 weeks. Tumors developed at the site of injection of 1,8-DNP in 6 of 15 mice up to 60 weeks after the first injection. The incidence of tumors was statistically significant at a P-value of less than .05 but not of less than .01. Therefore, the carcinogenicity of 1,8-DNP in BALB/c mice was concluded to be weaker than that of benzo[a]pyrene [(BP) CAS: 50-32-8], which induced a 100% tumor incidence when it was injected at the same dose as that of 1,8-DNP. No tumors occurred at the injection site in mice given 1,3-DNP. Most of the tumors induced by 1,8-DNP and BP showed histologic features characteristic of malignant fibrous histiocytoma.

Animals↗
PubMed1987

[Alkaline phosphatase activity in human gliomas as revealed by light and electron microscopy].

Precise localization of alkaline phosphatase (ALPase) activity in human gliomas was examined by light and electron microscopy in association with malignant transformation, paying much attention to changes in blood-brain barrier. Materials used were eight cases of gliomas four of which were astrocytoma grade 2, one astrocytoma grade 3, and three, glioblastoma multiforme, respectively. Specimens were quickly fixed in cacodylate-buffered 2% glutaraldehyde at 4 degrees C for 1 hour and rinsed overnight in the same buffer. Frozen or nonfrozen sections (40 microns thick) were made and incubated at 20 degrees C for 40 min, and processed for light and electron microscopy. For the demonstration of ALPase activity, the lead citrate method (Mayahara et al., 1967) was employed. By light microscopy, ALPase activity appeared to be mainly restricted to the capillary wall. By electron microscopy, reaction product representing ALPase activity was distributed in the plasma membrane of endothelial cells both in astrocytomas and in glioblastoma. In astrocytoma grade 2, activity was primarily localized along the abluminal surface of endothelial cells. In glioblastoma, on the other hand, ALPase activity was positive on the luminal surface of the plasma membrane of endothelial cells. It was much more intense than that along the abluminal surface. Regional differences in enzyme cytochemistry may represent functional heterogeneity in the endothelial cell membrane. In brain tumors, changes in distribution pattern of enzyme activity were visualized in the present study in association with glioma malignancy. This might represent a functional aspect of changes in blood-brain barrier in human glioma tissue during course of its malignant transformation.

Adult↗
PubMed1987

ID sequences in the genes of three brain-specific proteins.

We characterized the brain-specific gene coding for rat S-100 protein beta-subunit and found three "brain identifier (ID)" elements, which have been proposed to regulate the gene expression in rat brain. The nucleotide sequences of these elements corresponded well with that of the consensus ID element and were clearly different from those of "ID-like" elements in rat beta B1-crystallin gene, etc. ID elements were also observed in the flanking regions of rat neuron-specific enolase and cholecystokinin genes, which were expressed in the neuronal cells. Direct repeats were observed in the regions flanking ID elements.

Animals↗
PubMed1987

[Relationship between interatrial pressure gradient and motion of the interatrial septum].

To evaluate interatrial septal motion throughout the cardiac cycle, echocardiograms of the septum were obtained by esophageal echocardiography simultaneously with left and right atrial pressures using Millar's micromanometers in nine subjects with sinus rhythm. There were four patients with atypical chest pain but with normal coronary arteries, two with old myocardial infarction, one with angina pectoris, one with aortic regurgitation and one with sick sinus syndrome. The relationship between interatrial pressure gradient (IAPG: left atrial pressure minus right atrial pressure) and the motion of the septum was examined. In all nine patients, the curves of IAPG showed two peaks near the second heart sound and during the atrial contraction period, and the motion of the septum throughout the cardiac cycle showed a similar pattern except during the late diastolic period. During atrial contraction the septum moved posteriorly (decrease in left atrial dimension) against the IAPG. Therefore, except during the atrial contraction period, the motion of the atrial septum is considered to be dependent on this pressure gradient. During the atrial contraction period, the direction of the septal movement might be dependent on the force of active contraction of the left atrial muscles.

Adult↗
PubMed1987

Carcinogenicity of bucetin in (C57BL/6 X C3H)F1 mice.

The carcinogenicity of bucetin [(3-hydroxy-p-butyrophenetidide) CAS: 1083-57-4], an antipyretic analgesic drug, was examined in 300 (C57BL/6 X C3H)F1 mice. Groups of 50 mice of each sex were treated with 1.5 or 0.75% bucetin in their basal diet for 76 weeks and then fed a basal diet for 8 weeks. Control groups were given a basal diet for 84 weeks. In 10 of 46 (22%) male mice given the high dose of bucetin and in 6 of 45 (13%) given the low dose, renal cell tumors were induced. Dysplastic lesions of the proximal tubules were frequently seen in the males given bucetin in a dose-related fashion. Neither tumorous nor preneoplastic lesions developed in the kidneys of bucetin-treated female mice and control animals. Papilloma of the urinary bladder in 1 male mouse and papillary or nodular hyperplasia in 9 mice of both sexes were observed in groups given the high dose of bucetin.

Aminophenols↗
PubMed1987

Effects of physical exercise training on cardiac function and graft patency after coronary artery bypass grafting.

The effects of physical exercise training after coronary artery bypass grafting on recovery of cardiac function and graft patency were studied in 115 patients. The patients were divided into Group I (N = 60) with and Group II (N = 55) without a scheduled rehabilitation program. The rate of graft patency was 98% in Group I and 80% in Group II. After operation, the exercise cardiac index and stroke index were significantly higher in Group I than in Group II. The exercise stroke index increased significantly in Group I, but not in Group II. The variables affecting graft patency, examined by a stepwise method, included double product, cardiac index, stroke index, and left ventricular end-diastolic pressure during postoperative exercise conditions, and postoperative exercise training. The multiple coefficient for these five variables was 0.459 (p less than 0.01). Our findings suggest that physical exercise training should be started as early as possible after coronary artery bypass grafting to improve graft patency and recovery of cardiac function.

Cardiac Output↗
PubMed1987

Tissue distribution of rat S-100 alpha and beta subunit mRNAs.

Using Southern blot analysis it is demonstrated that S-100 alpha and beta genes were found as single copies in the rat genome. S-100 alpha mRNA was not found at all in rat brain during the developmental period, but it was slightly detectable in muscle and kidney. S-100 beta mRNA was detected in rat brain, and its mRNA level increased during the developmental period. The different localizations of the subunits may be due to the specific expression of each gene in various tissues.

Aging↗
PubMed1987

[Tolerance and plasticity against the intracranial pressure in cases of chronic subdural hematoma in the aged brain].

A consecutive series of 94 patients with chronic subdural hematomas (CSDHs) was studied on compensation against intracranial pressure and tolerance, and plasticity from compression of CSDHs, comparing between 47 cases of the aged group over 70 years of age and 47 cases of the younger group under 69 years of age. Better compensation from compression of CSDHs in the aged group was demonstrated from the fact those of long duration from impact to onset of symptoms, few cases with signs of chronic intracranial hypertension and volume of hematoma over 100 ml. But, when CSDHs progressed over 100 ml in size, this compensation mechanism and also tolerance against increased intracranial pressure were deprived. Disturbance of consciousness and anisocoria were shown much more in the aged group on admission. Patients in the aged group demonstrated reduced brain reexpansion and poor clinical recovery during 3 months after surgery. CT performed on 3 months after surgery demonstrated persisting subdural fluid in 63% of cases in the aged group comparing with 8% of those in the younger group. There was significant difference about morbidity between two groups. These study suggests that the plasticity and elastance in the aged brain reduce because of brain atrophy and impairment of cerebral blood flow, then brain reexpansion and clinical improvement may participate in delay regardless of release from compression of CSDHs. It may be urged that the critical age maintaining the plasticity of the brain in cases with SDHs in 75 years of age.

Adolescent↗