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Biomedical subjects

T Ogata

Publications and source records attributed to T Ogata.

At least 325 records · Page 18Linked to original sources
PubMed1992

An autopsied case of dentatorubropallidoluysian atrophy with atypical pathological features.

This is a report of an autopsied case of dentatorubropallidoluysian atrophy (DRPLA) with atypical neuropathological findings. The patients was a 31-year-old female. Her clinical symptoms were epileptic seizures, cerebellar ataxia, choreoathetosis and dementia. A neuropathological examination revealed the fibrillary gliosis in various areas of the CNS and severe degeneration in the cerebellar cortex and nucleus fasciculi dorsalis in addition to a marked degeneration of the dentatorubropallidoluysian systems. The present case is diagnosed neuropathologically as DRPLA associated with the findings of chronic diphenylhydantoin intoxication and epileptic brain damage.

Atrophy↗
PubMed1992

Release of excitatory amino acids from cultured hippocampal astrocytes induced by a hypoxic-hypoglycemic stimulation.

An excess release of excitatory amino acids (EAA) is an important factor for postischemic brain damage. In the present communication, we demonstrate that cultured hippocampal cells release EAA after hypoxic-hypoglycemic treatment. The amounts of EAA released from astrocytes were appreciably above those released from neurons. Furthermore, the amount of aspartate released from astrocytes was comparable to that of glutamate, although the endogenous content of aspartate was one-fifth that of glutamate. The endogenous content of aspartate in astrocytes increased even after hypoxic-hypoglycemic treatment. These results suggests that ischemic neuronal death is due, at least in part, to the excitotoxicity of aspartate and glutamate derived from surrounding astrocytes.

Amino Acids↗
PubMed1992

Sex reversal in a child with a 46,X,Yp+ karyotype: support for the existence of a gene(s), located in distal Xp, involved in testis formation.

We report on a sex reversed Japanese child with a 46,X,Yp+ karyotype, minor dysmorphic features, and no testicular development. The Yp+ chromosome was derived by translocation of an Xp fragment (Xp21-Xp22.3) to Yp11.3. This has resulted in deletion of distal part of the Y chromosome pseudoautosomal region (DXYS15-telomere) and duplication of the X specific region (DXS84-PABX) and proximal part of the pseudoautosomal region (MIC2-DXYS17). No deletion of the Y specific region was detected nor was any mutation found in SRY. Cytogenetic analysis suggests that the proximal part of the Xp fragment is the most distal part of the short arm of the Yp+ chromosome (Xp21----Xp 22.3::Yp11.3----Yqter). No chromosomal mosaicism was detected. These results are similar to previous reports of sex reversal in four subjects with a 46,Y,Xp+ karyotype. We conclude that the sex reversal is a direct, or indirect, consequence of having two active copies of the distal part of Xp and may indicate the presence of a gene(s) which acts in the testis determination or differentiation pathway.

Base Sequence↗
PubMed1992

Comparison of adult height between patients with XX and XY gonadal dysgenesis: support for a Y specific growth gene(s).

Adult height was compared between published cases of patients with XX gonadal dysgenesis (XXGD) and those with XY gonadal dysgenesis (XYGD). The mean adult height of XYGD patients (171.0 cm (SD 7.8), n = 27) was significantly greater than that of XXGD patients (164.4 cm (7.7), n = 27) (p less than 0.01). This finding supports the existence of a Y specific growth gene(s) which promotes statural growth independently of the effects of gonadal sex steroids.

Adult↗
PubMed1992

Chromosomal localisation of a pseudoautosomal growth gene(s).

Although recent molecular studies in patients with sex chromosome aberrations are consistent with a growth gene(s) being present in the pseudoautosomal region (PAR), the precise location has not been determined. In this report, we describe a Japanese boy and his mother with an interstitial deletion in Xp22.3 and review the correlation between genotype and stature in six cases of partial monosomy of the PAR. The results indicate that the region from DXYS20 to DXYS15 is the critical region for the putative growth gene(s).

Abnormalities, Multiple↗
PubMed1992

Giant air cell of the petrous apex: a possible cause of facial hypalgesia.

A giant air cell of the left petrous apex was found in a 23-year-old man with ipsilateral facial hypalgesia. The size of the giant air cell depicted on computed tomography was 1.5 x 2.0 x 2.0 cm. A coronal T1-weighted magnetic resonance image showed that the trigeminal nerve was compressed superomedially by a large signal void area that was probably a result of excessive pneumatization of the petrous apex. It is suggested that the facial hypalgesia was caused by the compression by the giant air cell of the petrous apex on the trigeminal nerve.

Adult↗
PubMed1992

Scanning electron microscopic study on the three-dimensional structure of the collagen fibrillar framework in the chronic active hepatitis and liver cirrhosis.

The three-dimensional collagen framework of human liver parenchyma in surgical specimens from patients with chronic active hepatitis (CAH), viral or alcoholic cirrhoses (LC) was observed by scanning electron microscopy after cell-maceration by the method of Ohtani (1988). In control livers, the tubular sheaths of collagen fibers housing the sinusoid were shown to form a labyrinthine network, which we called the perisinusoidal collagen sheaths (PSCSs), and a loose band-like collagen sheath was seen embracing each hepatocyte, which we called the perihepatocellular collagen sheath (PHCS). In CAH, thin septa partially surrounded the lobules, but the PHCS and PSCS appeared almost unchanged. In viral LC, thick collagen septa surrounded pseudolobules of various sizes. In these conditions, the collagen density was slight in PSCSs, while in PHCSs, it was prominent and associated with an enlargement of sheaths themselves. In alcoholic LC of mixed type, the basic structure of the collagen framework closely imitated that of viral LC.

Collagen↗
PubMed1992

Ultra-high-resolution scanning electron microscopic studies on the sarcoplasmic reticulum and mitochondria of the rat intrafusal muscle fibers. Part II: The extracapsular region.

The three-dimensional structure of the transverse-axial tubular system, sarcoplasmic reticulum (SR) and mitochondria in the extracapsular region of the intrafusal muscle fibers of the rat lumbrical muscle was observed by ultra-high-resolution scanning electron microscopy after removal of the cytoplasmic matrix by the osmium-DMSO-osmium procedure. Nuclear chain fibers possessed thick to moderately sized column-forming mitochondria with occasional I-band branches. The transverse tubules (T-tubules) running at the level of the A-band side of the A-I junction were sandwiched between two large terminal cisternae for most of their length, forming triads. The sarcotubules arising from the terminal cisternae formed single-layered networks at the A-band level, and well developed, double-layered, three-dimensional networks at the I-band level. Nuclear bag1 fibers possessed slender column-forming mitochondria devoid of I-band branches. The T-tubules were located at the level of the A-I junction. Both the T- and the axial-tubules were occasionally coupled with small terminal cisternae, forming dyads or triads. At the I-band level, the SR was well developed and formed single layered networks, but at the A-band level only a few longitudinally arranged sarcotubules and axial tubules were observed. Nuclear bag2 fibers contained medium to large diameter column-forming mitochondria without I-band branches. The T-tubules ran at the level of the A-band adjacent to the A-I junction, and were coupled at some intervals with terminal cisternae of various lengths. Swollen, large terminal cisternae were frequently seen.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[Quantitative DNA image cytometry by color image analyzer].

We developed a new method to analyze DNA quantitatively by a color image analyzer. A microscopic image of the nucleus stained with Feulgen's reaction, is taken by a CCD color camera and inputted in a color image analyzer. DNA quantity can be calculated directly from the RGB components of the color image instead of the monochrome image taken through band-pass filter, which is specific for the absorption of Feulgen's stain. It takes about 10 minutes to measure 500 nuclei by this method and its accuracy is almost the same as flow cytometry (CV = 3%). The nuclear color image can also be analyzed morphometrically. This method can select tumor cells in a usual cytologic specimen and measure their DNA contents.

Cytophotometry↗
PubMed1992

Short stature in a girl with a terminal Xp deletion distal to DXYS15: localisation of a growth gene(s) in the pseudoautosomal region.

This report describes a Japanese girl with short stature and a rearranged X chromosome. Her height remained below the 3rd centile growth curve for Japanese girls, and her predicted adult height (148.5 cm) was below her target height (163 cm) and target range (155 to 171 cm). Cytogenetic studies showed that the rearranged X chromosome was formed by a breakage at q26 and a transfer of the Xq fragment onto the tip of Xp. The abnormal X was always late replicating. No mosaicism was detected. Molecular analysis showed an Xp terminal deletion distal to DXYS15. Biochemical and radiological studies for short stature disclosed no abnormality. On the basis of height analysis of previous reports and a genotype-phenotype correlation of this patient, we propose that a growth gene(s) is present in the distal part of the pseudoautosomal region.

Blotting, Southern↗
PubMed1992

[Thoracoscopic laser coagulation shrinkage of blebs in the treatment of spontaneous pneumothorax].

As a thoracoscopic treatment for spontaneous pneumothorax, electrocautery has been mainly used. But contact type electrocautery has a risk of perforation of blebs. We adopted carbon monoxide laser (wave length 5.4 microns) and good coagulation shrinkage of blebs could be obtained by non-contact irradiation. CO laser was delivered by As-S glass fiber and power of fiber tip was 2-4 W. Compared with Nd-YAG laser (wavelength 1.06 microns), CO laser showed lower risk of perforation of blebs. Thoracoscopic CO laser coagulation shrinkage of blebs proved to be a important method of treatment for patient of spontaneous pneumothorax.

Humans↗
PubMed1991

Expression of Id, a negative regulator of helix-loop-helix DNA binding proteins, is down-regulated at confluence and enhanced by dexamethasone in a mouse osteoblastic cell line, MC3T3E1.

The message of Id (for "inhibitor of DNA binding") was expressed in an osteoblastic cell line, MC3T3E1, when the cells were in early cultures, while undetectable after the cells became confluent. The abundance of Id message in MC3T3E1 cells in early cultures was increased when the cells were treated with dexamethasone. This effect was time and dose dependent in a range between 10(-11)M and 10(-7)M. Id message expression was not enhanced by TGF-beta, 1,25-dihydroxyvitamin D3, retinoic acid, interleukin 1-alpha, interleukin 6, tumor necrosis factor-alpha or parathyroid hormone. These observations indicate for the first time the presence of HLH protein family member, Id, in osteoblast-like cells and its regulation by dexamethasone.

Actins↗
PubMed1991

[Histopathological evaluation of the radiosensitizing effects of an intratumoral injection of BrdU for rectal cancer].

We delivered preoperative radiotherapy with intratumoral injection (ITI) of radiosensitizer, 5-bromodeoxyuridine for patients with locally advanced cancer originating in lower rectum. We identified immunohistochemically the tumor cells that incorporated BrdU, and evaluated the radiosensitizing effect of BrdU histopathologically. (1) BrdU-labeled nuclei of cancer cells were identified in twenty-three cases out of 24 (96%). Mean labeling index was 18.5%, and tended to decrease as time progressed. (2) The parameters representing volume of residual tumor nests (Tumor Nest Index) or degrees of tumor extension (Depth of Extramural Tumor and Depth of Extramural Fibrosis) for patients with ITI were compared to those for patients without ITI. Those parameters tended to decrease when ITI was combined with radiotherapy. However, the difference was not significant statistically. Intratumorally injected BrdU can incorporate with cancer cells, but a methodological invention is required for yielding clinically measurable radiosensitization.

Adenocarcinoma↗
PubMed1991

Pulmonary blastoma with a topographic transition from blastic to more differentiated areas. An immunohistochemical assessment of its embryonic nature using stage-specific embryonic antigens.

In order to investigate the probable embryonic nature of pulmonary blastoma, immunohistochemical studies were performed using stage-specific embryonic antigens (Ley, Lex, sialyl Lex-i) in case of pulmonary blastoma with a very wide spectrum of morphological features. The tumour presented a topographic transition from primitive blastic and embryonic areas to more differentiated areas showing diverse differentiation. Blastic areas composed of extremely immature cells were found in most peripheral parts of the tumour. Inside the blastic areas there were "embryonic" areas which morphologically resembled human embryo lungs in the pseudoglandular and canalicular stages. Most central parts of the tumour showed more differentiated features including chondrosarcomatous, leiomyosarcomatous and rhabdomyosarcomatous elements and the common type of adenocarcinomatous element. Electron microscopic observation suggested the blastic and embryonic nature of these immature cell elements. Ley was expressed in the blastic and pseudoglandular areas. Lex was expressed in the canalicular areas. These antigens were not expressed in the more differentiated areas. The topographic gradient in the tumour of morphology and antigen expression from the peripheral blastic areas to the central more differentiated areas suggests that the primitive cells gradually differentiated into more mature cells of various directions as the tumour grew in size.

Antigens↗
PubMed1991

Expression of MHC class II antigens in human lung cancer cells.

Surgical specimens of lung cancers were examined immunopathologically for the expression of major histocompatibility complex class II (MHC-II) antigens in the tumor cells and their relationship to the lymphocytic infiltration. A lymphocytic infiltrate was frequently observed in the tumor tissue, though its intensity differed among the various histological types. MHC-II antigens were often demonstrated in tumors with a lymphocytic infiltrate. They were detected predominantly in the cytoplasm of tumor cells and to a lesser extent on the cell membranes. The emergence of the MHC-II-positive tumor cells was closely related to a local infiltration by lymphocytes including interferon-gamma (IFN-gamma)-producing T-cells. On the basis of the histological findings, an in vitro experiment was carried out. Four types of lung cancer cells were incubated with recombinant IFN-gamma in order to induce MHC-II antigens. MHC-II antigens (HLA-DR as well as HLA-DQ and HLA-DP antigens) were elicited in three cancer cell lines depending on the concentration of IFN-gamma. Immunoelectron microscopic study revealed that they were expressed on the surface of the cell membrane, though to a lesser extent than in the cytoplasm. It was considered that MHC-II antigens could be induced in some tumor cells in the immunological environment where IFN-gamma was secreted from T-cells and concentrated locally.

HLA-DQ Antigens↗
PubMed1991

Clinical significance of serum levels of a carbohydrate antigen, sialyl SSEA-1, in patients with fibrosing lung disease.

Serum levels of sialyl SSEA-1 antigen, a carbohydrate antigen, were measured by radioimmunoassay in 142 patients with nonmalignant lung diseases. In 20 of 41 patients with fibrosing lung disease, either idiopathic or associated with collagen disease, the serum sialyl SSEA-1 levels were abnormally elevated. In patients with other lung diseases, the serum levels were almost within normal limits, less than 38.0 units/ml. In fibrosing lung disease the serum levels ranged from 13.8 to 147.0 units/ml and were largely concurrent with the degree of disease activity. The therapeutic effects of corticosteroid, which were evaluated with clinical-radiographic-physiologic scores and survivals in the patients with elevated serum levels, were significantly lower than those of the patients with the normal range of antigen levels. An immunohistochemical study performed on autopsied lungs from five patients with fibrosing lung disease indicated that the antigen was selectively expressed in the pulmonary epithelial cells that covered the remodeling alveolar septi in the lungs. No antigen was detectable by immunostaining in normal pulmonary epithelium among five normal lungs. From these findings, it is thought that the elevated levels of serum sialyl SSEA-1 may be derived from proliferating epithelial cells that were dominant in the late stage of fibrosing lung disorders. The measurements of serum sialyl SSEA-1 in patients with fibrosing lung disease may be clinically useful in establishing the degree of disease activity that has an influence on patient prognosis and therapeutic response.

Adrenal Cortex Hormones↗
PubMed1991

Ultra-high-resolution scanning electron microscopic studies on the sarcoplasmic reticulum and mitochondria of the rat intrafusal muscle fibers. Part I. The capsular sleeve region.

The three-dimensional structure of the transverse-axial tubular system, sarcoplasmic reticulum (SR) and mitochondria in the capsular sleeve region of the intrafusal muscle fibers of the rat lumbrical muscle was observed by ultra-high-resolution scanning electron microscopy after removal of the cytoplasmic matrix by the osmium-DMSO-osmium procedure. Nuclear chain fibers were seen to have slender I-band limited mitochondria, and thick column-forming mitochondria which occasionally exhibited I-band branches. The transverse tubules (T-tubules) ran at the level of the A-band side of the A-I junction and were sandwiched between two large terminal cisternae for most of their length, forming triads. The sarcotubules arising from the terminal cisternae formed single-layer networks at the A-band level, and well developed, double-layer, three-dimensional networks at the I-band level. Occasionally, tetrads and pentads were also seen. Nuclear bag2 fibers possessed column-forming mitochondria of medium size, practically devoid of I-band branches. The T-tubules ran at the level of A-band adjacent to the A-I junction and were coupled with terminal cisternae of various lengths at intervals. As a rule, the SR formed single-layered networks at the level of the A-band and double-layered networks at the I-band level, and was less developed than in chain fibers. Nuclear bag1 fibers contained slender column-forming mitochondria devoid of I-band branches. The T-tubules were located at the level of the A-I junction. Both the T- and the axial-tubules were occasionally coupled with small terminal cisternae, forming dyads or triads. At the I-band level, the SR was well developed and formed single layer networks, but at the A-band level only a few longitudinally arranged sarcotubules and axial tubules were recognized.

Animals↗