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Biomedical subjects

T Ogata

Publications and source records attributed to T Ogata.

At least 271 records · Page 15Linked to original sources
PubMed1994

A marked increase in intracellular Ca2+ concentration induced by acromelic acid in cultured rat spinal neurons.

Acromelic acid, a kainate derivative of natural origin, markedly increased intracellular Ca2+ concentration ([Ca2+]i) in cultured rat spinal neurons in a concentration dependent manner; the half effective concentration (EC50) was 1.3 microM. Acromelic acid was more potent in increasing [Ca2+]i than any other glutamate receptor agonists tested, and the rank order of the activity was as follows: acromelic acid > alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) > kainate > N-methyl-D-aspartate (NMDA) > L-glutamate. Acromelic acid did not increase the [Ca2+]i in a Ca(2+-)free medium. 2,3-Dihydroxy-9-nitro-7-sulfamoylbenzo(F)quinoxaline (NBQX) completely inhibited the [Ca2+]i increase induced by acromelic acid. These results suggest that the [Ca2+]i increase was not through Ca2+ mobilization from intracellular stores but due to Ca2+ influx mediated by the activation of non-NMDA receptors. Acromelic acid increased the [Ca2+]i in rat hippocampal neurons as well; however, the EC50 (6 microM) was considerably higher than that in spinal neurons. The marked increase of [Ca2+]i in cultured spinal neurons would explain, at least in part, the earlier findings that systemic administration of acromelic acid causes selective degeneration confined to lower spinal interneurons.

Animals↗
PubMed1994

Expression of the multidrug resistance gene (MDR1) in non-small cell lung cancer.

To ezamine the clinical relevance of P-glycoprotein, encoded by the human multidrug resistance gene (MDR1), to multidrug resistance in lung cancer, we examined the expression of MDR1 in 107 non-small cell lung cancer (NSCLC) specimens and 20 corresponding specimens of normal lung tissues. We also evaluated the relationship between MDR1 expression and the histopathology and pathological staging of NSCLC. The tumors consisted of 60 adenocarcinomas, 38 squamous cell carcinomas, 8 large cell carcinomas, and 1 adenosquamous carcinoma. MDR1 expression was semi-quantified by use of the reverse transcriptase-polymerase chain reaction method. We subclassified the NSCLC into 3 grades according to the MDR1 expression level (-, +, ++). Sixty-one of the 107 tumor specimens (57%) and 18 of the normal lung tissue specimens (90%) expressed various levels of the MDR1 gene. Only one tumor specimen showed higher MDR1 expression than the corresponding normal lung tissue. The relationship between pathological stage and MDR1 expression levels was not significant. These results suggest that the level of MDR1 expression in lung cells is decreased as cells progress from the normal to the transformed state.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Comparative DNA analysis by image cytometry and flow cytometry in non-small cell lung cancer.

To determine whether image cytometry (ICM) is advantageous for clinical DNA analyses of tumor cells, nuclear DNA contents measured by ICM were compared with those by flow cytometry (FCM), using 46 samples of non-small cell lung cancers. ICM was performed on smear specimens of fresh materials (f-ICM) and cell suspensions obtained from paraffin-embedded tumors (p-ICM). The same cell suspensions were also analyzed by FCM (p-FCM). Aneuploid rates/coefficient of variation (CV) of f-ICM, p-ICM, and p-FCM were 76.1/4.90, 71.7/5.01 and 60.9/5.31%, respectively. There was a high correlation in the DNA indices between p-ICM and p-FCM (r = 0.80). In the comparative DNA analysis, there were seven discordant samples. Six of them were estimated as aneuploid by p-ICM, but they were miscounted as diploid or undefinable (impossible) by p-FCM. This was caused by measuring condensed nuclei or debris. All "impossible" samples in p-FCM were squamous cell carcinoma with necrosis. In cell cycle analysis, the S and S+G2/M phase fractions in diploid samples were higher in p-ICM than those in p-FCM (P < 0.005), because the G0/G1 phase (2N) fraction presented by FCM was composed of cancer and non-malignant cells in diploid cancers. In ICM, they can be separately measured by means of morphological selection. These findings indicated that ICM is superior to FCM, especially for the practical DNA measurement of a few cancer cells and in the evaluation of the proliferation rates.

Adult↗
PubMed1994

Expression of tumor-associated glycoantigen, sialyl Lewis(a), in human head and neck squamous cell carcinoma and its application to tumor immunotherapy.

The glycoantigen sialyl Lewis(a) (sLe(a)) is widely expressed on a variety of gastrointestinal tumor cells. Here, we immunohistochemically demonstrated the expression of sLe(a) antigen in 54% (7 out of 13) of human head and neck squamous cell carcinoma (H-NSCC) samples. Frequent expression of sLe(a antigen was also demonstrated on a variety of H-NSCC cell lines using flow cytometry. Both CD4+ and CD8+ T cells, which were activated with immobilized OKT3 monoclonal antibody plus interleukin-2, showed augmented cytotoxicity against sLe(a)-positive H-NSCC, including autologous tumor cells, on targeting with anti-CD3 x anti-sLe(a) bispecific antibody, suggesting that sLe(a) antigen is a good target molecule for bispecific antibody-dependent adoptive tumor immunotherapy of human head and neck cancer.

Adult↗
PubMed1994

Clinicopathological study on a case of neuro-Behçet's disease: in special reference to MRI, SPECT and neuropathological findings.

A case of neuro-Behçet's disease with dementia and personality changes is described with magnetic resonance imaging (MRI), single photon emission tomography (SPECT) and neuropathological findings. MRI disclosed high signal areas in the cerebral white matter and the brain stem. SPECT showed a marked reduction of blood flow in the frontal cortex. Neuropathologically, multifocal necrotizing lesions with perivascular lymphocytic infiltration and glial proliferation were detected mainly in the brain stem, namely the midbrain and the pons. From these findings, it is suggested that mental disorders of neuro-Behçet's disease are related to the secondary dysfunction of the frontal cortex due to the damage of the subcortical structures, mainly the brain stem.

Behcet Syndrome↗
PubMed1994

An autopsied case of acute lymphocytic meningoencephalitis with a long clinical course: special reference to CT, MR, SPECT and neuropathological findings.

This report describes the clinico-pathological features of acute lymphocytic meningoencephalitis (ALME) of a patient with a long clinical course of 24 months. The patient rapidly developed a confusional state, occasionally with stupor, various involuntary movements and generalized convulsions followed by fever and headache at the age of 29. Clinical symptoms, except fever and convulsions, had not distinctly improved throughout the clinical course, and cortical atrophy on CT and MR gradually progressed. SPECT revealed a low blood perfusion in the cerebral cortices. Neuropathologically, inflammatory findings were very mild, but nerve cells degenerated prominently. From these clinicopathological findings, it is suggested that chronic degenerative changes followed an acute inflammatory phase.

Adult↗
PubMed1994

Empyema and mediastinitis complicating retropharyngeal abscess.

A 21 year old man with a retropharyngeal abscess complained of right sided chest pain, and chest radiography and thoracocentesis revealed an empyema. A computed tomographic scan of the chest showed a posterior mediastinal abscess communicating with the right pleural cavity. Emergency thoracotomy was performed and the mediastinal abscess and empyema were drained.

Acute Disease↗
PubMed1994

[Adult Wilms's tumor with histologically dissisimilar lung metastasis].

A 41-year-old man incidentally found to have a right renal and left large lung tumor in the course of screening for liver dysfunction was admitted to our hospital. Needle biopsy of each tumors revealed histologically renal cell carcinoma and pulmonary blastoma. The renal tumor grew rapidly and soon he died of DIC. Autopsy was performed and the final diagnosis was adult Wilms' tumor and its metastasis to the lung. Histological findings of each large tumors showed different histologic pattern. The renal tumor revealed diffuse nephroblastic subtype and the lung tumor showed epitherial type. This is a rare case of Wilms' tumor in terms of its adult onset and different histologic pattern between the primary tumor and its metastatic lesion.

Adult↗
PubMed1994

A new method for palliation of malignant obstructive jaundice utilizing a peritoneo-venous shunt pump.

A new simple palliative method for use in malignant obstructive jaundice is presented. This method is particularly effective in the prevention of ascending infections. The method consists of interposing a one-way flow shunt pump (peritoneo-venous shunt pump) between a bile catheter and a jejunal catheter. Four patients were treated with this new method. Jaundice improved significantly in all patients. They had a much better quality of life with no serious complications during the terminal course. This less invasive and safe procedure is preferred for patients who have extrahepatic biliary obstruction due to incurable malignant tumors.

Aged↗
PubMed1994

Scanning electron microscopic study of the three-dimensional structure of the collagen networks of gastric cancer.

The three-dimensional structure of the collagen networks in human gastric carcinoma was examined by scanning electron microscopy (SEM) after treatment with the cell-maceration method using a low temperature NaOH solution. Based on stromal content, the poorly differentiated adenocarcinoma can be divided into the medullary carcinoma area and the scirrhous carcinoma area. In the medullary carcinoma, the collagen sheath around the small tumor cell acinus formed spherical chambers (20-30 microns in diameter) with fenestrations (about 5 microns in diameter) connecting the chambers. The collagen sheath was composed of fine collagen fibrils (about 50 nm in diameter). In the scirrhous area, there was abundant fibrous stroma composed of thicker collagen fibrils (about 100 nm in diameter). Tiny tumor cell nests were sporadically seen in the fibrous stroma. These tumor nests were surrounded by collagen fibrils (about 50 nm in diameter). In the moderately differentiated tubular adenocarcinoma, the tumors were surrounded by spherical, ovoid or irregular shaped thick collagen sheaths (50-200 microns in diameter), which were composed of loosely packed 50 nm collagen fibrils. In well differentiated tubular adenocarcinoma, tumor glands were surrounded by spherical, ovoid or irregularly-shaped thick collagen sheaths (50-200 microns in diameter), composed of densely arranged fine collagen fibrils. In papillary carcinoma, the collagen sheaths were nipple-shaped. They were composed of very densely arranged fine collagen fibrils (about 50 nm in diameter).

Adenocarcinoma↗
PubMed1994

Scanning electron microscopic study of the collagen sheath of the human thyroid gland and its disorders.

A cell-maceration/scanning electron microscope (SEM) method was employed to demonstrate the collagen sheath around follicles (perifollicular sheath) of the human thyroid gland and its disorders. In the normal thyroid gland, the follicles were surrounded by spherical collagen sheaths composed of a framework of thick collagen bands 1-5 microns in width and fine solitary collagen fibrils 50-70 nm in diameter. In benign thyroid diseases (Graves' disease, Hashimoto's thyroiditis and adenomatous goiter), the perifollicular sheaths differed in size and in shape according to the disease, but they were always composed of thick collagen bands and fine fibrils as in the normal thyroid. On the other hand, the spaces surrounded by the perifollicular sheaths varied markedly in size in follicular adenoma, were small in oxyphilic adenoma, and irregularly shaped in embryonal adenoma. In all these adenomas, the perifollicular sheaths were mainly composed of fine fibrils 35-45 nm in diameter. In follicular carcinoma, the size and shape of the space surrounded by the perifollicular sheaths were irregular. In papillary adenocarcinoma, the collagen sheaths showed a papillary pattern. In medullary carcinoma, tumor nests were surrounded by well developed collagen sheaths. In all these carcinomas, the collagen sheaths were mainly composed of fine collagen fibrils 32-45 nm in diameter. In adenomas and follicular carcinoma, the perifollicular sheaths frequently had large holes through which the spaces surrounded by the collagen sheaths connected to each other. Such holes were, however, rare in the normal thyroid and benign non-neoplastic thyroid diseases.

Collagen↗
PubMed1994

Colorectal carcinoma metastatic to skeletal muscle.

Skeletal muscle is one of the most unusual sites of metastasis from any malignancy. We report on a case of skeletal muscle metastasis from colonic carcinoma, and review seven previously reported cases. The patient was a 66-year-old man who exhibited a painful metastatic mass in the right major teres muscle six months after surgery for colonic carcinoma. He underwent three operations and one course of arterial infusion chemotherapy, but died of carcinoma after two years and seven months. In seven previous cases and in the present case (3 males and 5 females, aged between 30 and 75 years), the sites of the primary lesion and metastatic lesion in skeletal muscle were diverse. The interval between primary carcinoma and relapse ranged from synchronous to 5 years. Spontaneous pain in the recurrent region was a characteristic symptom. Surgical removal of the metastatic lesions relieved pain. Prognosis was considered poor. However, complete resection of the metastatic lesion at a time when no other recurrent lesions were present might have cured the patient.

Adenocarcinoma↗
PubMed1994

[Serum and tissue levels of cefodizime in the pediatric patients].

We administrated cefodizime (40 mg/kg) to 13 patients with simple herniorrhaphy in the pediatric field and determined its concentrations in tissues and serums. The mean serum and tissue levels of cefodizime after administration were 43.1 +/- 13.3 micrograms/ml, and 23.1 +/- 6.4 micrograms/g, respectively, at 3 hours. Cefodizime concentrations of the tissue and serum were maintained at relatively high levels for many hours. The ratio of cefodizime concentrations in tissue to serum became high at 3 hours after administration, and this suggests that tissue concentrations decreased more slowly than serum levels, and cefodizime concentrations in tissue were maintained at fairly high levels over a long period. No side effects caused by cefodizime were observed. From pharmacokinetic and clinical observations, cefodizime appears to be a safe and effective injectable antibiotic for the treatment of infections in children.

Bacterial Infections↗
PubMed1994

[Thoracoscopic resection of mediastinal tumors].

Thoracoscopic surgery was performed in nine patients with benign mediastinal tumors: four neurogenic tumors, three bronchogenic cysts, a foregut cyst and a mature teratoma. Four cystic masses located in para-esophageal lesion in inferior mediastinum and four neurogenic tumors located in posterior mediastinum. A mature teratoma was adjacent to thymus in anterior mediastinum. Under general anesthesia with unilateral ventilation, the patients were turned in the lateral decubitus position and we tilt the operative table to allow gravity assistance for the displacement of the lung. A rigid telescope was inserted through a thracoport. Masses were resected using the dissecting scissors with electric cautery through two other thracoports. Thoracoscopic complete resections were performed in eight patients. In one case that was suspected of malignant tumor by preoperative evaluation, thoracoscopic tumor biopsy was performed and diagnosed as a benign neurogenic tumor during operation histopathologically. But it was resected by thoracotomy, because of its larger size (8 cm in diameter). The average operation time was 122 minutes ranging from 80 to 184 minutes in 8 patients with thoracoscopic resection. No patient has a complication resulting from the thoracoscopic surgery. The chest drainage tubes were removed on 1 or 2-POD in all cases and the average length of postoperative hospitalization was 5.3 days ranging from 4 to 9 days. The thoracoscopic resection for benign mediastinal tumors is minimally invasive and effective procedure compared with classical thoracotomy operation.

Adolescent↗
PubMed1994

[Sleeve S6 segmentectomy for early bronchial squamous cell carcinoma--a case report].

A 60-year-old male complaining cough was referred to our hospital. His chest roentgenogram showed left hilar abnormal shadow and his sputum cytology was reported to be class V. Bronchoscopy revealed a squamous cell carcinoma of the orifice of the left B6. It suggested early hilar carcinoma with obstructive pneumonia. We performed sleeve segmentectomy of the S6 with bronchoplastic procedure. Bronchial wall invasion of squamous cell carcinoma was observed histologically and it was confirmed as early hilar lung cancer. His postoperative course was uneventful and no evidence of recurrence is observed 12 months after operation. Patency of the basal bronchus is excellent and his vital capacity and forced expiratory volume in one second are almost equal to preoperative values. In such early hilar lung cancer that occupied the orifice of the B6, the margin of oral side bronchus resected by sleeve S6 segmentectomy is almost same as by lower lobectomy. We believed that this procedure can be minimum invasive standard operation in such cases.

Bronchi↗