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Biomedical subjects

T Ogata

Publications and source records attributed to T Ogata.

At least 253 records · Page 14Linked to original sources
PubMed1995

[Experimental and clinical study on intraoperative local infusion chemotherapy (ILIC) for advanced gastric carcinoma].

An intensive chemotherapy combined with surgery, termed "intraoperative local infusion chemotherapy (ILIC)", was devised. The ILIC procedure is to infuse 50 mg of cisplatin through the feeding artery to the tumor, which has been isolated from blood flow by clamping the stomach and blood vessels, before radical surgery. An experiment in dogs showed considerable free Pt transfer into thoracic lymph after ILIC. Sum total Pt in the thoracic lymph after ILIC (294.5 micrograms/3 h) was 4.3 times that after IV administration (68.3 micrograms/3 h). In ILIC, AUC of free Pt in the thoracic lymph was about 5.8 times that in peripheral blood. ILIC was applied in 24 advanced gastric cancer patients, consisting of 6, 2, 4 and 12 in pTNM stage II, IIIA, IIIB and IV, respectively. Pt concentration of the tissues was high in the tumor (23.22 micrograms/g) and the regional lymph nodes (2.95 micrograms/g) compared to that in the serum (0.45 microgram/ml). The survival rate (Kaplan-Meier) in the ILIC patients was significantly higher than that of control patients (matched pair method) from among patients treated by surgery alone. No fatal complications were encountered in any patient treated by ILIC.

Animals↗
PubMed1995

Immunohistochemical analysis of dendritic/Langerhans cells in thyroid carcinomas.

Recent immunohistochemical investigations of thyroid carcinomas have revealed that dense infiltration by dendritic cells (DCs) is correlated with a favorable prognosis. The present study was done to clarify the frequency and characteristics of DC infiltration in thyroid carcinomas, and also cytokines associated with DC maturation and migration. Compared with follicular carcinomas, papillary carcinomas contained significantly higher numbers of DCs, interleukin (IL)-1 alpha- and tumor necrosis factor (TNF)-alpha-positive cells, and cells positive for two TNF-alpha receptors (p60 and p80). The centers of cancer nodules had large numbers of CD1a- and CD1c-positive DCs suggesting that they were Langerhans cells, whereas the periphery of cancer nodules and inflamed surrounding thyroid tissues had numerous CD1b-, L-M2- and X-12-positive DCs suggesting that they were interdigitating cells, as well as many CD1a- and CD1c-positive DCs. Neoplastic cells of papillary carcinomas were more frequently reactive with antibodies against IL-1 alpha and TNF-alpha than those of follicular carcinomas, and a good correlation between their immunoreactivity and the frequency of DCs was found. These data suggest that cytokines such as IL-1 alpha and TNF-alpha released from carcinoma cells and cells in the cancer stroma may regulate the infiltration and maturation of dendritic/Langerhans cells, and that this process may be better preserved in papillary than in follicular carcinomas.

Adenocarcinoma, Follicular↗
PubMed1995

Extraordinarily high eosinophilia and elevated serum interleukin-5 level observed in a patient infected with Paragonimus westermani.

OBJECTIVE: Although eosinophilia is one of the typical clinical features of some helminth infections, the degree of eosinophilia in helminthiasis is usually 10% to 30% with a total white blood cell count of 10,000 to 20,000/mm3. Here we report a case of extraordinarily high eosinophilia (91%; absolute eosinophil count, 84,000/mm3) caused by Paragonimus westermani infection. To determine the mechanisms of eosinophilia, the levels of several eosinophilopoietic cytokines in the patient's sera were measured during the course of treatment. METHODS: Serum levels of three cytokines, granulocyte-macrophage colony-stimulating factor, interleukin-3 (IL-3), and IL-5 were measured by enzyme-linked immunosorbent assay using commercial kits or our own assay system for IL-5. RESULTS: Although the kinetic changes of IL-5 correlated well with eosinophilia, the serum IL-3 level remained below the detection level throughout the period examined. Although the granulocyte-macrophage colony-stimulating factor level was twofold to threefold higher than the normal level, its kinetics did not parallel the degree of eosinophilia. CONCLUSIONS: These results show that Paragonimus westermani infection can induce an extraordinarily high level of eosinophilia with an associated increase in IL-5 production. Immunoserologic diagnosis for parasitic diseases should be included in the differential diagnosis of eosinophilia.

Animals↗
PubMed1995

The effect on tinnitus of stapes surgery for otosclerosis.

Among 42 Japanese patients with otosclerosis who underwent stapes surgery, 22 patients including 10 received total stapedectomy, 6 partial stapedectomy and 6 stapedectomy, were investigated on preoperative and postoperative tinnitus by sending questionnaire. The tinnitus was evaluated by "tinnitus score" advocated by the Japan Audiological Society, and the changes of the scores were analyzed according to pre- and postoperative hearing change, type of stapes surgery and pitches of preoperative tinnitus. In these 22 patients, tinnitus score was improved in 68%, unchanged in 27% or worsened in 5%. Tinnitus was completely disappeared in 6 patients or 27.3%. Tinnitus score became more markedly improved in the patients received partial stapedectomy or stapedotomy than those who received total stapedectomy. Tinnitus score was more likely improved in the patients who had a low pitched tinnitus and presumably had no cochlear otosclerosis preoperatively.

Adult↗
PubMed1995

Corneal epithelium in keratoconus.

Specular microscopy was employed to study the corneal epithelium of 20 keratoconus patients (17 male, 3 female, average age 23.9 +/- 6.6 years). The patients were divided into three groups based on the severity of the keratoconus; early, intermediate, and advanced. Initially, epithelial changes were limited to enlargement of the superficial cells. As the disease progressed, elongated cells became prominent. Irregularly configurated and nucleated epithelial cells were observed in all cases. Morphomeric analysis showed that the mean area of the corneal epithelial cells was 906 +/- 203 microns 2 in the early stage, 1,416 +/- 521 microns 2 in the intermediate stage, and 1,641 +/- 372 microns 2 in the advanced stage. The shape factor was 0.32 +/- 0.05, 0.76 +/- 0.22, and 0.81 +/- 0.17, respectively. Controls were chronic wearers of hard contact lenses without corneal pathology. Analysis of their epithelium revealed no abnormalities. This finding suggests that the epithelial changes observed in keratoconus are not due to the wearing of contact lenses, but rather to the disease itself.

Adolescent↗
PubMed1995

Electron microscopic study on the regenerating epithelium of the chronic gastric ulcer.

Specimens from 31 cases of human gastric ulcers and 3 ulcer scars obtained at surgery were studied by transmission and scanning electron microscopy. A layer of simple cuboidal epithelial cells arising at the margin of the gastric ulcer migrated toward the ulcer base. Two types of regenerating epithelium (RE) were found: gastric and intestinal cell types. The gastric cell type RE originated from the gastric epithelium and was composed of immature cells which later matured to form primitive gastric glands. The intestinal cell type RE migrated from the intestinal metaplasia bordering the ulcer and contained immature cells which developed into absorptive and goblet cells forming primitive crypts and villi. In both types of RE, the basal lamina was frequently lacking. Moreover, degeneration and necrosis were often seen, especially in severe inflammatory focus. Profiles of Helicobacter pylori were observed in the gastric lumen, on the gastric type RE in about one third of the cases, but they were never found on the intestinal type RE.

Gastric Mucosa↗
PubMed1995

Three-dimensional configuration of crypts of different types of colorectal adenomas.

The three-dimensional configuration of isolated crypts of normal human colonic mucosa and colorectal adenomas was examined by scanning electron microscopy. For isolation of the crypts, the digestion method with HC1 was used for formalin fixed tissues, and the separation method with ethylenediaminetetraacetic acid (EDTA) following ultrasonication was applied to fresh tissues. In a comparative study, the NaOH cell-maceration method, which visualized the sub-basal laminal collagen sheath, was applied. The isolated crypts from the normal colon were visualized as a single straight tubule resembling a test tube. Most isolated crypts of the tubular adenomas were visualized as elongated fan-like structures with several protuberances and a few short branchings. Their average length was more than twice that of the normal colonic mucosa crypts. Most crypts of the villous adenomas were visualized as slender tubules without protuberances and short branchings, and their average length was three times that of the tubular adenoma crypts. Most crypts of the tubulovillous adenomas were long and triangular with several longitudinal folds and protuberances, and the average length was about three times that of the tubular adenoma crypts.

Adenoma↗
PubMed1995

Scanning tunneling microscopic study of osmium-impregnated collagen.

The vapor-phase osmium impregnation method was applied to increase the conductivity of the collagen specimens used in scanning tunneling microscopy (STM), since the application of STM to biological materials has been limited by the poor conductivity, irregular sample geometry, and instability of these materials. The impregnation method was applied to collagen fibrils attached to highly oriented pyrolytic graphite, and the STM images obtained were compared with those of routinely processed uncoated specimens. The osmium-impregnated collagen fibrils showed a periodicity of about 67 nm, which was also observed on the negative-stained specimens by transmission electron microscopy. In addition, the periodicity of 3.1 nm, which corresponded to the helical cycle of the 3 alpha-chains within collagen, was clearly demonstrated by STM. Moreover, the comparative observations of collagen specimens without osmium impregnation disclosed the left-handed helical structure with a periodicity of 3.1 nm in a single collagen filament.

Animals↗
PubMed1994

A novel peridinin-chlorophyll a protein (PCP) from the marine dinoflagellate Alexandrium cohorticula: a high pigment content and plural spectral forms of peridinin and chlorophyll a.

A new type of peridinin-chlorophyll a protein (PCP) was isolated from the marine dinoflagellate Alexandrium cohorticula. Unlike previous studies. PCP was obtained as a single component in the presence of a protease inhibitor. The monomer had a molecular mass of 37 kDa with 12 peridinin molecules associated with 2 chl a molecules. This pigment content was much higher than that reported previously. We observed a partial amino acid sequence of the N-terminus that is novel among photosynthetic pigment-protein complexes. Magnetic circular dichroism clearly indicated that chl a in PCP had monomeric features. Multiple spectral components were suggested for both chl a and peridinin. Based on the high pigment content, the optical properties were compared with those for a reported PCP containing 4 chl a and 1 peridinin.

Amino Acid Sequence↗
PubMed1994

Endoscopic criteria of early squamous cell carcinoma of the bronchus.

BACKGROUND: Early lung cancer, not extending beyond the bronchial cartilaginous layer without regional lymph node involvement is considered curable by endoscopic laser therapy or limited surgery. The endoscopic criteria for early squamous cell carcinoma of the bronchus, however, have not yet been determined. METHODS: For 44 resected lesions of roentgenographically occult bronchogenic squamous cell carcinomas, the relationship between endoscopic findings and the degree of histologic extent of tumor was examined. RESULTS: The lesions were divided into three types: polypoid or nodular (PN), flatly spreading (FS), and mixed. Thirty-three lesions arising from the central bronchus included 7, 19, and 7 of the PN, FS, and mixed types, respectively. In the central lesions, the degree of transmural invasion and the greatest dimension correlated, but the degree of intramural invasion of PN-type lesions was higher than that of the FS type. The PN-type lesions smaller than 10 mm and the FS type smaller than 15 mm in greatest dimension were found within the cartilaginous layer without regional lymph node involvement. All lesions of the mixed type were larger than 20 mm. Three of the lesions larger than 20 mm had regional lymph node involvement. All 11 lesions originating in the peripheral bronchus were of the FS type, and a lesion of only 5 mm in greatest dimension had extracartilaginous invasion. CONCLUSIONS: The endoscopic criteria of early squamous cell carcinoma of the bronchus may be applied to central PN lesions smaller than 10 mm and central FS lesions less than 15 mm in greatest dimension. Any lesions of mixed type should be excluded from the criteria.

Aged↗
PubMed1994

Neuroectodermal tumors expressing c-, L-, and N-myc in transgenic mice that carry the E1A/E1B gene of human adenovirus type 12.

Adenovirus early 1 (E1) region gene products, including E1A and E1B, are required for transformation of primary cultured rodent cells. In order to investigate in vivo action of the E1 region, we established a line of transgenic mice carrying the oncogenic E1A and E1B genes of human adenovirus type 12 under control of the human angiotensinogen promoter. Histopathological analyses indicated that transgenic mice heritably develop neuroectodermal tumors arising from the pelvic region with varying degrees of incidence. The transgene was expressed in the neuroectodermal tumors as well as in TNT-1 cells, a cell line established from the tumors, where the human angiotensinogen promoter was constitutively active. The high level expression of c-, L-, and N-myc without gene amplification was notable in the original tumors and TNT-1 cells, but not in another tissue examined. The co-expression of the three sets of myc family genes in both the original tumors and the established cell line provided the possibility that the target cells for transformation may belong to a specific cell type that expresses all these oncogenes during development.

3T3 Cells↗
PubMed1994

Proliferating cell nuclear antigen and Ki-67 in lung carcinoma. Correlation with DNA flow cytometric analysis.

BACKGROUND: To study the prognosis of patients with lung carcinomas, the efficacy of proliferating cell nuclear antigen (PCNA) in ensuring both the proliferative activity defined using Ki-67 labeling and the cell cycle data obtained using flow cytometry was determined. METHODS: The authors used immunostaining to study frozen and paraffin embedded sections of 165 surgically resected lung carcinomas [squamous cell carcinoma, n = 84; adenocarcinoma, n = 62; large cell carcinoma, n = 15; small cell carcinoma, n = 4] for the presence of PCNA and Ki-67 antibodies. Also studied were two parameter flow cytometric analysis of fluorescein isothiocyanate conjugated PCNA/propidium iodide for 165 fresh frozen tissues. Clinicopathologic data (sex, age, tumor stage, survival period, histologic type, degree of cell differentiation, and cellularity) were evaluated using the Statistical Analysis System. RESULTS: The percentages of PCNA positive cells per 1000 nuclei were 52% of squamous cell carcinoma; 49% in adenocarcinomas; 76% of large cell carcinoma; and 63% of small cell carcinoma. Positive PCNA staining was significantly correlated with stage, cellularity, and DNA index. Calculation of logistic regression coefficients indicated an association between overall survivals and tumor cellularity (P < 0.0003), percentage of cells stained with PCNA antibody (P < 0.02), DNA pattern (aneuploid versus diploid) (P < 0.009), DNA index (P < 0.009), and percentage of cells in S-phase (P < 0.04). Both cellularity (P = 0.03) and DNA (P = 0.08) retained its independent level of significance by multivariate analysis. CONCLUSIONS: In addition to clinical stage and histologic differentiation, both cellularity and DNA content may help predict the course of lung carcinomas.

Adenocarcinoma↗
PubMed1994

Rapid decrease in ATP content without recovery phase during glutamate-induced cell death in cultured spinal neurons.

Glutamate neurotoxicity in the cultured neurons from rat spinal cord was evaluated on the basis of endogenous ATP content in the cells. A short exposure of the neurons to glutamate induced an immediate and rapid decrease in ATP content. Then, after removal of glutamate, no recovery of ATP content was observed for 24 h, eventually resulting in neuronal death. These findings suggest that the glutamate-induced neuronal death in vitro is apparently similar to but essentially different from so-called 'delayed' neuronal death in vivo after a brief ischemia in hippocampal CA1 neurons in which a transient recovery of ATP level occurs after its dramatic reduction.

Adenosine Triphosphate↗
PubMed1994

Protection of thyroid cancer cells by complement-regulatory factors.

BACKGROUND: Clinical and experimental studies have suggested that complement activation may play a role in tumor cytotoxicity. Little information is available concerning the presence of complement activation and the localization of complement-regulatory factors in cells or tissues of malignant tumors. The aim of the present study was to examine, using immunohistochemistry and immunoelectron microscopy, whether the complement system is activated in tissues of thyroid carcinoma and whether thyroid carcinoma cells are protected from cell lysis by in situ complement activation. METHODS: Fresh tissues were obtained by thyroidectomy from 15 patients with papillary carcinomas, 7 with follicular carcinomas, and 5 with follicular adenomas. In addition, five specimens of histologically normal thyroid tissue and five specimens of chronically inflamed tissue adjacent to thyroid neoplasms were studied. Immunohistochemical and immunoelectron microscopic localization of complement components, C3d and C5b-9, and the complement-regulatory factors, such as s-protein, decay-accelerating factor (CD55), membrane cofactor protein (CD46), complement receptor types 1 (CD35) and 2 (CD21), and protectin (CD59), were examined in these tissues. RESULTS: The staining patterns of C3d, C5b-9, and s-protein were positive and homogeneous in the nonneoplastic and most neoplastic thyroid tissues. Immunoelectron microscopy showed these antigens were localized mainly on the subepithelial and vascular basement membranes and attached to the cell surface of thyroid follicular cells. Decay-accelerating factor (CD55) was present homogeneously on the basement membranes, on the basal cell border of the thyroid follicular cells, and often on the luminal surface of carcinoma cells. Both membrane cofactor protein (CD46) and protectin (CD59) were expressed strongly on the cell surface of almost all benign and malignant thyroid follicular cells. Membrane cofactor protein was expressed on both the basal and lateral membrane, showing cell-to-cell interaction, but rarely on the luminal surface, whereas protectin was expressed strongly on the luminal surface and often on the basal cell border but rarely on the lateral membrane. Neither complement receptor type 1 (CD35) nor complement receptor type 2 (CD21) was expressed on any thyroid follicular cells. CONCLUSIONS: The present study confirmed the presence of complement activation with subsequent deposition of C3d and C5b-9 complexes in thyroid carcinomas. It also indicated that thyroid carcinoma cells are protected from cell lysis because of complement activation in multiple phases by complete coverage of the entire cell membrane surface with complement-regulatory factors. These findings were similar to those found in nonneoplastic thyroid follicular cells.

Adenoma↗
PubMed1994

Adenosine enhances intracellular Ca2+ mobilization in conjunction with metabotropic glutamate receptor activation by t-ACPD in cultured hippocampal astrocytes.

2Cl-Adenosine, a non-metabolized adenosine agonist, enhanced the increase in intracellular Ca2+ concentration ([Ca2+]i) in cultured hippocampal astrocytes induced by (+-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (t-ACPD), a metabotropic glutamate agonist. In the absence of 2Cl-adenosine, the half effective concentration (EC50) of t-ACPD was about 80 microM. On the other hand, in the presence of 1 microM 2Cl-adenosine, the EC50 of t-ACPD shifted to about 5 microM, although the maximum [Ca2+]i did not change. The synergistic effect of 2Cl-adenosine with t-ACPD on [Ca2+]i elevation was not inhibited by the elimination of extracellular Ca2+, but was inhibited by A1-specific adenosine antagonists. These results indicate that adenosine can act via the A1 receptor as an endogenous co-activator of the metabolic processes induced by metabotropic glutamate receptor activation.

Adenosine↗
PubMed1994

Effects of vitamin A on proliferation of human distal airway epithelial cells in culture.

Using a serum-free culture method, we investigated the effects of vitamin A on the proliferation of human distal airway epithelial cells. Outgrowth of epithelial cells from lung tissue explants was enhanced by treatment with all-trans retinol at concentrations of 10(-8) to 10(-7) M. The colony-forming activity of cells harvested from the primary culture and replated onto Swiss 3T3 fibroblastic feeders was, in contrast, significantly reduced by 10(-7) M to 10(-5) M retinol. When the primary cells were harvested and subcultured on Primaria plates, population expansion was also inhibited by retinol at 10(-10) to 10(-6) M. We further investigated the cells to determine whether there was any difference in sensitivity to the growth-inhibitory effects of vitamin A between cells from the primary culture incubated with and without retinol. The population increase in cells harvested from the primary culture was inhibited equally in retinol-treated and non-treated cells by subsequent treatment with retinol or retinoic acid, this inhibition being dose-dependent. DNA synthetic activity was also inhibited. Interestingly, both the growth rate and the colony-forming efficiency on feeders were greater in the subculture of cells from the retinol-treated primary culture than in those non-treated. When the cells in the secondary subculture were treated with retinoic acid and replated again, they showed a greater population increase rate than those non-treated. Our results showed that human distal airway epithelial cells isolated from lung tissue were sensitive to the growth-inhibitory effect of vitamin A, but the proliferative potential in some fraction of the epithelial cell population was possibly enhanced by vitamin A treatment.

3T3 Cells↗
PubMed1994

T cell cytotoxicity of autologous and allogeneic lymphocytes in a patient with Crohn's disease.

We report a 27-year-old male with Crohn's disease (CD) of the small and large intestine, whose peripheral blood lymphocytes (PBL) showed increased cell-mediated cytotoxicity (CTL). Autologous and allogeneic effector cells from PBL and intestinal lymph nodes (LN) were isolated on a Ficoll-Hypaque gradient. Colonic cells were prepared as the target and were incubated for 6h with effector cells, after being labeled with Na(2)51CrO4. The CTL activity [effector/target (E/T) ratio, 100:1] of PBL for autologous targets was increased by 38% compared with that in normal subjects (< 10%), while that shown by LN was not increased (14%). The CTL activity of allogeneic PBL prepared from three of four other CD patients was also increased. Anti-major histocompatibility (MHC) class I and II and CD4 and CD8 monoclonal antibodies (50 micrograms/ml) significantly inhibited CTL activity. Complement-mediated depletion of CD2+ cells significantly reduced CTL activity. These results suggest that MHC-restricted CTL may play a role in mucosal damage in some patients with Crohn's disease.

Adult↗