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T Kodama

Publications and source records attributed to T Kodama.

At least 811 records · Page 45Linked to original sources
PubMed1987

Comparison of microdissected sections from the human cataractous lens by antisera to synthetic peptides.

Polyclonal antiserum has been made against beta crystallin from human lens, and against synthetic peptides corresponding to the N- and C-terminal sequences of bovine beta Bp crystallin. A solid-phase radioimmunoassay has been used to quantitate binding of these antisera to soluble proteins from microdissected sections. The results of this analysis demonstrate the feasibility of using radioimmunoassay analysis in combination with peptide antisera to determine statistically significant changes in protein antigenicity from opaque versus transparent regions from the same human cataractous lens.

Cataract↗
PubMed1987

Optimal positioning for CT examinations of the skull base. Experimental and clinical studies.

To evaluate the most appropriate CT angles for the skull base, four adult phantom skulls of various shapes were examined by CT. 15 osseous sites in each skull base were selected and the optimum angle for their delineation was determined. Using Reid's base line (0 degree), many sites could be imaged best at angles up to +20 degrees, and +10 degrees was found to be optimum. Examinations of patients using OM-line as a reference disclosed imaging rates in excess of 70% for sites other than the hypoglossal canal, the optic canal and foramen rotundum, which are in horizontal planes.

Adolescent↗
PubMed1986

Markov-dependency and spectral analyses on spike-counts in mesencephalic reticular neurons during sleep and attentive states.

Spontaneous activities of the mesencephalic reticular formation (MRF) neurons of head-restrained cats were recorded to investigate their dynamic properties during sleep and waking. The Markov-dependency and spectral analyses were performed on the time series of counts converted from the MRF spike-train. During slow-wave sleep (SWS), MRF neurons fired with low Markovian properties and had a similar spectral-density curve as white noise; during paradoxical sleep (PS), their firing pattern showed high Markovian properties owing to low-frequency fluctuations, with spectral densities inversely proportional to frequency (the l/f spectrum). During the attentive state of bird watching (BW), intermediate Markovian properties were observed. These results confirmed both the rest theory of SWS and the activation of the brain during PS from the viewpoint of dynamic information-processing. Furthermore, the activation of the brain during PS may be greater than in BW.

Animals↗
PubMed1986

Neuroradiologic findings of hypothalamic hamartoma with emphasis on computed tomography.

Hypothalamic hamartoma is a relatively rare congenital malformation. Five new cases and 31 cases in the literature were evaluated in regard to neuroradiologic findings with emphasis on computed tomography. Five important computed tomography findings were observed: oval-shaped, isodense suprasellar mass; clear demarcation; no enhancement effect; absence of cystic component or calcification; and no effacement of the third ventricle. Clinical features, mechanism of the precocious puberty, and differential diagnosis are also discussed.

Child↗
PubMed1986

Subtypes of small cell carcinoma of the lung: morphometric, ultrastructural, and immunohistochemical analyses.

Fifty-three surgically resected small cell carcinomas of the lung were studied morphometrically, electron microscopically, immunohistochemically, and in terms of possible site of origin. Four subtypes of small cell carcinomas were identified: oat cell carcinoma (OAT), small cell carcinoma of the intermediate cell type (INT), combined oat cell carcinoma, and undifferentiated carcinoma of the small cell type (UCS). The latter type is presumed to be non-neuroendocrine. Morphometric analysis showed considerable overlap among OAT, INT, and UCS with respect to nuclear area, cell area, and nuclear/cytoplasmic ratio. Ultrastructurally, significantly more carcinomas categorized as OAT and INT contained neurosecretory granules than did those in the UCS category (P less than 0.01 and 0.05, respectively). Cells with tonofibrils were more frequent in UCSs than in OATs and INTs. Immunohistochemically, fewer UCSs than OATs contained cells with gastrin-releasing peptide, neuron-specific enolase, and Leu-7 (P = 0.5, P less than 0.05, and P less than 0.05, respectively). UCSs were located more frequently at the periphery of the lung than were OATs (P less than 0.01) and INTs (P = 0.06). These findings suggest that UCS may be a pathologic entity distinct from the typical neuroendocrine-type small cell carcinoma and that this subtype probably corresponds to small cell carcinoma with a "large cell component," and to very poorly differentiated adenocarcinoma and squamous cell carcinoma of the small cell type.

Carcinoma, Small Cell↗
PubMed1986

Morphometric study of adenocarcinomas and hyperplastic epithelial lesions in the peripheral lung.

Mean nuclear areas (MNA) were calculated morphometrically in ten cases of well-differentiated adenocarcinoma, ten cases of atypical alveolar cuboidal cell hyperplasia (AAH), and five cases of alveolar cuboidal cell hyperplasia (AH) and were compared with each other. In cases of adenocarcinoma, the MNA were significantly larger than those of AAH and AH, and the standard deviation (SD) of nuclear area was greater in adenocarcinoma than that in AAH and AH, thus implying greater "scatter" of the nuclear areas in the former than the latter two. The MNA and the SD of nuclear area in AH were smallest in these three groups. In one case each of AAH and adenocarcinoma, there were two different populations of nuclear size in the same lesions, that is, histograms showed both adenocarcinoma and AAH in the same tumor. Through the use of the morphometric method, many cases of AAH were easily distinguishable from adenocarcinoma cases, and there were two cases in which foci of adenocarcinoma and AAH coexisted.

Adenocarcinoma↗
PubMed1986

The initial phosphate burst in ATP hydrolysis by myosin and subfragment-1 as studied by a modified malachite green method for determination of inorganic phosphate.

The Malachite Green method for determination of inorganic phosphate (Pi) (Itaya K. & Ui, M. (1966) Clin. Chim. Acta 14, 361-366) was modified to measure Pi in the range of 0.2-15 nmol per ml of ATPase reaction mixture. An ATPase reaction mixture is quenched with an equal volume of 0.6 M PCA; the supernatant after centrifugation is mixed with an equal volume of the Malachite Green/molybdate reagent containing 2 g of sodium molybdate, 0.3 g of Malachite Green and 0.5 g of Triton X-100 or Sterox SE in 1 liter of 0.7 M HCl, and the absorbance at 650 nm is then measured after a 35-40 min incubation at 25 degrees C. Owing to the high sensitivity and simplicity of the modified method, the slow time course of myosin ATP hydrolysis in the presence of Mg2+ and the size of initial phosphate burst can be determined accurately using relatively low concentrations of native myosin and its subfragment-1. The phosphate burst size varied with changes in pH, ionic strength, and temperature. A typical value was 0.8-0.9 mol per site in 0.1 M KCl, 10 mM MgCl2, pH 8.0 at 25 degrees C for fresh enzyme preparations.

Adenosine Triphosphatases↗
PubMed1986

Immunohistochemical cell kinetic study of human lung cancer by using monoclonal antibody to bromodeoxyuridine.

In vitro cell kinetic studies of 27 surgically removed human lung cancers were performed by the immunohistochemical procedure using monoclonal antibody to bromodeoxyuridine (BrdU). BrdU was incorporated under hyperbaric oxygenation, and labeled cells were found to be evenly distributed in the tissue blocks. A comparison of the in vitro and in vivo labeling index (L.I.) in human tumors transplanted to nude mice showed good correlation. Surgically resected adenocarcinoma of the human lung had a significantly lower L.I. than squamous cell carcinoma, the mean values being 6.0% and 17.2%, respectively. In adenocarcinoma, L.I. values disclosed a trend toward a higher L.I. in poorly differentiated carcinoma.

Animals↗
PubMed1986

An immunohistochemical study of thymic epithelial tumors. I. Epithelial component.

Twenty-four cases of thymic epithelial tumors, including 18 cases of thymoma, five cases of squamous cell carcinoma, and one case of undifferentiated carcinoma, were studied immunohistochemically using monoclonal antibody Leu-7 (HNK-1) and antikeratin antibody. Seven cases of non-neoplastic thymic tissues were also studied. Leu-7 antibody stained epithelial cells in the outer cortex of the normal thymus, and antikeratin antibody stained thymic epithelial cells in both cortex and medulla of the normal thymus. Seventeen thymomas and one undifferentiated carcinoma were focally or diffusely stained with Leu-7, some showing cortical and medullary differentiation as seen in the normal thymus. On the other hand, none of the five squamous cell carcinomas were stained with Leu-7. All thymomas stained for keratin in varying degrees, and all squamous cell carcinomas were diffusely and strongly stained with antikeratin antibody. It is concluded that normal thymic epithelial cells showed zonal differentiation, and neoplastic cells were considered to retain these characteristics to some extent; i.e., thymomas had the same phenotype of epithelial cells of the cortex, especially the outer cortex of the thymus in some instances (Leu-7-positive, keratin-positive) and of both cortex and medulla (mixture of Leu-7-positive and -negative cells) with organoid arrangement in other instances, and thymic squamous cell carcinoma had the same phenotype as epithelial cells in the thymic medulla (Leu-7-negative, keratin-positive).

Antigens, Surface↗
PubMed1986

Papillary adenoma of type 2 pneumocytes.

A case of papillary adenoma of type 2 pneumocytes is reported. A 57-year-old man had an unusual coin lesion in the periphery of the right lung without any symptoms. When detected in a mass survey examination, it was approximately 1.5 cm in diameter, well circumscribed, and located in S4, involving the sixth-order bronchus of B4. Light-microscopic examination revealed cuboidal tumor cells arranged in a papillary pattern. Ultrastructurally, the cells had characteristic osmiophilic lamellar bodies. By immunoperoxidase staining, the tumor cells were shown to have intracytoplasmic surfactant apoproteins. The postoperative course was uneventful, and there is no evidence of disease 8 years later.

Cystadenoma↗