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T Maeda

Publications and source records attributed to T Maeda.

At least 1,063 records · Page 59Linked to original sources

[Application of the immunohistochemical method as predictive assay in radiotherapy of squamous cell carcinoma].

We analysed various subsets of lymphocytes infiltrated into cancer tissues from 15 patients (10 cases of oropharyngeal cancer and 5 of hypopharyngeal cancer) at pretreatment and at about 10 Gy and 30 Gy of irradiation by the method of biotin-avidin-horseradish peroxidase using mouse monoclonal antibodies. In 3 cases, tumor infiltrating lymphocytes were remarkably increased at the delivery of small dose of irradiation: Two of them showed remarkable radiosensitivity, and the lymphocyte subpopulation of the cancer tissue was mainly composed of Leu3a + 3b positive, Leu-8 negative and Leu-HLA-DR positive lymphocytes (activated helper inducer T lymphocytes). On the other hand, the third one proved to be rather radioresistant and the lymphocyte subpopulation was mainly composed of Leu-14 positive lymphocytes (B lymphocytes). These findings indicate that the analysis of the lymphocyte subpopulation infiltrating into cancer tissues at the delivery of small dose of irradiation is applicable as a predictive assay in radiotherapy of squamous cell carcinoma of oropharynx and hypopharynx.

Adult↗

Potassium permanganate used to eliminate interference with the Porter-Silber reaction in the butanol extraction method for determination of urinary 17-hydroxycorticosteroids.

We describe a simple, rapid, and less interference-susceptible method for using the Porter-Silber reaction for determination of urinary 17-hydroxycorticosteroids. The procedure is based on butanol extraction of the steroids after the urine sample is treated with potassium permanganate and sodium bisulfite. These treatments, together with an additional acid- and alkali-washing of the extract, could eliminate most of the substances in urine that interfere with the Porter-Silber reactions. Values so obtained correlated well (r = 0.95) with those by Furuya's method in which beta-glucuronidase is used. Our method may be useful and suitable for a screening test of adrenocortical and pituitary functions.

1-Butanol↗

[Angioblastic meningioma with metastases to the vertebra and adjacent bones: a case report].

A case of angioblastic meningioma with multiple metastases to the vertebra and the adjacent bones is presented. A 60-year-old man was admitted to our hospital complaining of pain in the left arm, right chest and abdominal wall, the left buttock, and on the posterior surface of the both legs. He had first undergone subtotal removal of tentorial meningioma eight years before admission. Histological diagnosis of angioblastic meningioma was confirmed. He subsequently received radiation therapy when the tumor recurred six years before admission and again underwent subtotal removal of the recurrent tumor, followed by radiation therapy, four years before admission. Bone scintigrams demonstrated abnormal uptake of radionuclide by the vertebral arches of Th 1, Th 10, Th 11, the vertebral bodies of L 4, L 5, the right 7th rib, and the left iliac bone. Myelography and CT examination with intrathecal infusion of metrizamide revealed marked cord-compression by the space-occupying lesions at the level of the first and the tenth thoracic vertebral bodies. Chest roentgenograms, ultrasonograms and whole body CT examinations showed no other lesions. The tumor was partially resected from the iliac lesion. The diagnosis of metastatic meningioma was confirmed by the histological findings. Postoperative radiation therapy to the first, tenth, and eleventh portions of the thoracic vertebra, and the fourth and the fifth portions of the lumbar vertebra--the causative lesions of the pain--relieved the pain.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Neoplasms↗

[Arterial perfusion study with 99mTc-MISA in monitoring intra-arterial chemotherapy of head and neck tumor].

RI-angiography with 99mTc microsphere albumin (MISA) was performed to evaluate the distribution during intra-arterial infusion chemotherapy from October 1985 to November 1987 at Tokyo Women's Medical College. Thirty studies were carried out in twenty-one patients with oropharyngeal (11), oral cavity (6), maxillary sinus (3) and laryngeal cancer (1). Six mCi of 99mTc-MISA was slowly injected through the intra-arterial catheter in 1-2 minutes. The evaluation of RI-distribution was classified into the following three categories: Excellent, all of the tumor are covered; Good, more than 50% of the tumor; Poor, less than 50% of the tumor. Good or excellent distribution was obtained in 18 of 21 cases (86%). Sequential perfusion studies were performed on 8 cases. Three cases had evidenced excellent or good distribution during the treatment. Five cases showed poor distribution in the first study. In three of these cases, distributions were improved after replacement of the catheter, RI-distribution at the internal carotid arterial area was seen in three patients, and in two of them, excellent or good distribution was obtained after replacement of the catheter. These data suggested that RI angiography with 99mTc-MISA was useful for evaluation of the drug distribution during intra-arterial infusion chemotherapy, especially for detection of abnormal distribution in the internal carotid arterial area.

Adult↗

Initial-rate studies of a thermophilic glucokinase from Bacillus stearothermophilus.

The initial rates of phosphorylation of glucose catalysed by glucokinase from Bacillus stearothermophilus were measured over a wide range of glucose, MgATP2-, MgADP- and glucose 6-phosphate concentrations. The results of the effects of the inhibitors on the initial rates suggest that the reaction mechanism is essentially the ordered Bi Bi, in which glucose adds to the enzyme before MgATP2- and glucose 6-phosphate is released from the enzyme after the dissociation of MgADP-, and also suggest that the final step in which glucose 6-phosphate is released is irreversible. For many reaction schemes, the rate equations were derived on the basis of the pseudo-steady-state assumption and were used to correlate the experimental rate data. From this result, we concluded that the reaction obeys the ordered mechanism accompanied by the formation of a non-productive ternary complex, glucose-MgADP--enzyme. By using the experimental Dalziel coefficients phi i, some kinetic parameters were evaluated. The enzyme was characterized by the thermal stability and the low Michaelis constant, the values of which were 54 microM for glucose and 32 microM for MgATP2-.

Adenosine Diphosphate↗

Selective use of the VHQ52 family in functional VH to DJH rearrangements in a B precursor cell line.

AT11-2, an Abelson virus-transformed cell line has DJH complexes on both chromosomes and is able to form functional variable region genes by the joins of VH genes to the DJH complexes during culture. Therefore we examined which VH gene family was used in functional VH to DJH recombinations in AT11-2. Surprisingly, of 32 independent functional VH to DJH recombinational events in AT11-2, 31 events used the VH segments of the VHQ52 family, and the remaining one used the VH segment of the VH7183 family. Thus, we describe here the first B precursor cell line that almost selectively uses the VHQ52 family in functional VH to DJH rearrangements. The selective use of the VHQ52 family in this B precursor cell line strongly indicates nonrandom use of VH gene families, and the existence of a stage at which the VHQ52 family is preferentially used during the normal development of early pre-B cells and has important implications for understanding the ontogeny of VH repertoire development. Furthermore, this cell line should prove extremely valuable in further studies of this kind.

Animals↗

Start of mu-chain production by the further two-step rearrangements of immunoglobulin heavy chain genes on one chromosome from a DJH/DJH configuration in an Abelson virus-transformed cell line: evidence of secondary DJH complex formation.

A variant was selected from an Abelson virus-transformed cell line with identifiable and distinguishable DJH rearrangements on both chromosomes. Southern blotting experiments suggested that this variant resulted from a secondary DJH complex formation accompanied with the deletion of one of the DJH rearrangements on the same chromosome. Furthermore, this variant started making mu-chains by the further functional join of a VH gene to the secondarily formed DJH complex. Thus, we describe here the first evidence of a secondary DJH complex formation.

Abelson murine leukemia virus↗

Function of the 30 kd protein of tobacco mosaic virus: involvement in cell-to-cell movement and dispensability for replication.

We have investigated the function of the 30 kd protein of tobacco mosaic virus (TMV) by a reverse genetics approach. First, a point mutation of TMV Ls1 (a temperature-sensitive mutant defective in cell-to-cell movement), that causes an amino acid substitution in the 30 kd protein, was introduced into the parent strain, TMV L. The generated mutant showed the same phenotype as TMV Ls1, and therefore the one-base substitution in the 30 kd protein gene adequately explains the defectiveness of TMV Ls1. Next, four kinds of frame-shift mutants were constructed, whose mutations are located at three different positions of the 30 kd protein gene. All the frame-shift mutants were replication-competent in protoplasts but none showed infectivity on tobacco plants. From these observations the 30 kd protein was confirmed to be involved in cell-to-cell movement. To clarify that the 30 kd protein is not necessary for replication, two kinds of deletion mutants were constructed; one lacking most of the 30 kd protein gene and the other lacking both the 30 kd and coat protein genes. Both mutants replicated in protoplasts and the former still produced the subgenomic mRNA for the coat protein. These results clearly showed that the 30 kd protein, as well as the coat protein, is dispensable for replication and that no cis-acting element for replication is located in their coding sequences. It is also suggested that the signal for coat protein mRNA synthesis may be located within about 100 nucleotides upstream of the initiation codon of the coat protein gene.

Journal Article↗