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T Kameya

Publications and source records attributed to T Kameya.

At least 91 records · Page 5Linked to original sources
PubMed1995

Expression of bcl-2 oncogene protein is prevalent in small cell lung carcinomas.

To investigate the frequency of bcl-2 oncogene protein expression in small cell lung carcinoma (SCLC), immunohistochemical staining with a mouse-anti-human monoclonal antibody, bcl-2/124, was carried out on 60 formalin-fixed, paraffin-embedded SCLC samples obtained from surgical biopsy, and autopsy cases. bcl-2 protein was detected in 54 out of the 60 SCLCs. In 47 cases, more than half of the tumour cells stained positively. The staining intensity of the tumour cells was comparable to that of infiltrating lymphocytes in 37 cases, but varied from area to area and even from cell to cell. Negative data in six cases were found to be due to unsuitable fixation or embedding procedures rather than the absence of the antigen. bcl-2 oncogene protein may thus be expressed in most if not all SCLCs. bcl-2 may have potential diagnostic and therapeutic importance in SCLCs and non-SCLCs. Previous cytogenetic and molecular genetic analyses indicate that SCLCs carry a number of chromosomal abnormalities and it would follow from the present results that the abnormal expression of bcl-2 may also play a role in the pathogenesis of SCLC, by increasing tumour mass through inhibition of apoptosis as previously proposed. The diagnostic, prognostic, and therapeutic implications of these findings should be studied in greater detail.

Carcinoma, Small Cell↗
PubMed1995

Invasive meningioma: a tumour with high proliferating and "recurrence" potential.

A study was undertaken to investigate the correlation between histological invasiveness and proliferating potential and clinical recurrence in meningioma. In 39 meningiomas, the histological findings at the tumour-brain interface zone were classified into 3 types, consisting of 29 cases of non-invasion (NON). 7 cases of nodular invasion (NOD), and 3 cases of intermingled invasion (INT). Proliferating cell nuclear antigen (PCNA) and argyrophilic nucleolar organizer region (AgNOR) indices were studied. PCNA indices (mean +/- standard error) of NON, NOD. and INT were 1.7 +/- 0.1%, 5.2 +/- 0.5%, and 7.5 +/- 0.7%. respectively, and the AgNOR indices (dot number/nucleus) were 1.50 +/- 0.03, 2.00 +/- 0.04, and 2.22 +/- 0.07, respectively. Significant differences were found among the three types in both parameters. Clinically, tumour recurrence was observed in 1/29 NON, 4/7 NOD, and 2/2 INT cases, indicating a higher incidence of recurrence in invasive meningiomas (NOD plus INT). Four of 32 patients who underwent gross total removal of the tumours showed recurrence, and all of these four tumours were invasive meningiomas. The results of the present study showed that tumour invasiveness as measured by PCNA + AgNOR indices correlated well with high proliferative potential and clinical recurrence.

Adolescent↗
PubMed1995

Expression of nm23-H1 and nm23-H2 protein in endometrial carcinoma.

nm23 gene expression has been shown to be inversely correlated with tumour metastatic potential in some cancers but not in others. Examination was made of the expression of nm23-H1 and nm23-H2 gene products by immunohistochemistry and immunoblotting in 28 endometrial carcinomas. Immunohistochemistry indicated the cytoplasm of cancer cells to be positive, and myometrium and endometrial stromal cells negative, for nm23-H1 and -H2 protein. The staining intensity for these proteins was significantly stronger in well-differentiated adenocarcinomas (G1) than in those moderately differentiated (G2) (P < 0.05). nm23-H1 and -H2 proteins were shown by immunoblotting to be present at significantly higher levels in G1 than in G2 tumours (P < 0.05). Two of eight cases expressed high nm23-H1 and -H2 protein in poorly differentiated adenocarcinomas (G3). In G3 tumours, nm23 expression may be diverse. In this study, the expression of nm23-H1 and -H2 was not correlated with stage, metastasis, tumour size, myometrial invasion, oestrogen receptor, progesterone receptor or menopause. It follows from the findings presented above that the high expression of nm23-H1 and -H2 is positively correlated with histological differentiation.

Adult↗
PubMed1995

Basic fibroblast growth factor increases regional cerebral blood flow and reduces infarct size after experimental ischemia in a rat model.

BACKGROUND AND PURPOSE: The aim of this study was to ascertain whether basic fibroblast growth factors (bFGF) caused reduction in size of cerebral infarcts in Sprague-Dawley rats with experimental ischemia. METHODS: In the first experiment we induced permanent occlusion of the left middle cerebral artery (MCA). Within 5 minutes after MCA occlusion, we infused bFGF (100 ng in 0.1 mL of saline) in the bFGF-treated group (n = 14) and 0.1 mL of saline alone in the control group (n = 7) into the common carotid artery ipsilateral to MCA occlusion. We harvested the brains 24 hours after MCA occlusion and determined infarct size planimetrically as a percentage of hemisphere size. In the second experiment cerebral blood flow (CBF) was continuously measured for 120 minutes after MCA occlusion in the bFGF-treated group (n = 9) and in the control group (n = 8) with the use of laser-Doppler flowmetry. RESULTS: Infarct size in the bFGF-treated group decreased significantly in comparison with that in the control group (repeated-measures ANOVA, P < .0001). CBF in the transitional areas between the MCA and the anterior cerebral artery significantly increased in the bFGF-treated group in comparison with that in the control group (repeated-measures ANOVA, P < .005). An approximate 58% decrease in infarct size and a 40% increase in regional CBF were seen on bFGF treatment. CONCLUSIONS: The present study suggested that intracarotid administration of bFGF (100 ng) can reduce infarct size after MCA occlusion. It was speculated that the increased CBF in the penumbral areas of MCA may contribute to contraction of infarct size.

Animals↗
PubMed1995

Analysis of spinocerebellar ataxia type 1 (SCA1)-related CAG trinucleotide expansion in Japan.

Spinocerebellar ataxia type 1 (SCA1) is a neurodegenerative disorder caused by expansion of a CAG trinucleotide repeat. We analyzed CAG repeat expansion in 25 families in the northeast of Japan with hereditary ataxia of Menzel type. Twenty of 38 patients in 12 families had expanded allele for SCA1. The number of CAG repeats correlated with the age at onset. Although the relationship between anticipation and the number of CAG repeats in successive generations was not ascertainable, there was a tendency to paternal bias for the accelerated age at onset. Study of the number of CAG repeats in various tissues showed no differences in the repeat length in lymphocytes, muscle, or brain; sperm, however, showed an obvious expansion. This may be a clue to a possible mechanism for the molecular basis of paternal anticipation of the disease. The SCA1 gene was transcribed from both wild and mutated alleles in muscles of affected individuals, but the repeat length was the same for both the muscle cDNA and the lymphocyte genomic DNA. These results suggest that, in the area of Japan where SCA1 is prevalent, 48% of families with spinocerebellar degeneration have SCA1 mutation.

Adult↗
PubMed1995

Clinical and ultrastructural comparison of immunohistochemically inactive and gonadotropin-producing pituitary adenomas.

A clinicoendocrinological and ultrastructural comparison of immunohistochemically inactive pituitary adenomas from 14 patients and gonadotropin-positive pituitary adenomas from 26 patients was carried out. Clinicoendocrinological characteristics were similar except the male to female ratios. The immunohistochemically unstable antigenicity of gonadotropin prevents clear immunohistochemical characterization, but the difference between the two types is not absolute and may be an indication of a cell line relationship.

Adenoma↗
PubMed1995

p53 mutations and prognosis in bladder tumors.

The incidence of loss of heterozygosity on chromosome 17p and p53 gene mutations was assessed in 43 bladder tumor patients. Histological findings, cigarette smoking and prognosis were examined for possible correlation with the presence or absence of loss of heterozygosity on 17p and p53 mutations. Of 20 informative cases 10 (50.0%) showed loss of heterozygosity of 17p13, including 9 (90.0%) with disease beyond stage pT2. The p53 mutations were detected in 20 of 43 patients (46.5%), including 9 (95.0%) with disease beyond grade 2 and 17 (85.0%) with cancer beyond stage pT2. The incidence of p53 gene mutations was not significantly influenced by habitual smoking but G:C to T:A substitutions, often observed in lung cancers, were detected only in mutations from smokers (5 of 10 or 50%, p < 0.05). Groups with and without loss of heterozygosity showed essentially the same results, while significant differences were found for groups with grades 1 and 2 to 3 (p < 0.05) cancer, stages pT1 and pT2 to 4 (p < 0.01) disease, and with and without p53 gene mutations (p < 0.01, Cox-Mantel test). Genetic alternation in chromosome 17p and p53 mutations would, thus, appear to occur more frequently in high grade and invasive bladder tumors. Cigarette smoking may possibly be a determining factor of mutations of the p53 gene in bladder tumors. Our results indicate that an unfavorable prognostic factor may possibly be linked not only to histopathological findings but the presence of a p53 mutation in bladder tumors as well. Accordingly, mutations of the p53 gene may be deeply involved in late events of tumorigenesis and possibly useful as ideal molecular markers for prognosis in bladder tumors.

Adult↗
PubMed1995

Origin of ciliated craniopharyngioma: pathological relationship between Rathke cleft cyst and ciliated craniopharyngioma.

Histological study was undertaken on ciliated craniopharyngioma and Rathke cleft cyst, to know the origin of ciliated craniopharyngioma. Subjects were 7 cases with symptomatic Rathke cleft cysts and a ciliated craniopharyngioma. Light and electron microscopic observations were made on surgically resected specimens of the 8 cases. The ciliated craniopharyngioma was composed mainly of papillary type of craniopharyngioma and of dispersed ciliated columnar epithelium including goblet cells. Four cases with Rathke cleft cyst showed squamous metaplasia of which the basal cells were histologically similar to that of papillary type of craniopharyngioma. Other 3 cases of Rathke cleft cyst, basal cells were revealed to have tonofilaments and desmosomes. It seems possible that ciliated craniopharyngioma has derived from the basal cells of Rathke cleft epithelium.

Adult↗
PubMed1994

Glomus cell differentiation in the carotid body region of chick embryos studied by neuron-specific class III beta-tubulin isotype and Leu-7 monoclonal antibodies.

Development of the carotid body and the glomus cell groups in the wall of the common carotid artery and its branches was examined in chickens at various developmental stages by immunohistochemistry using three different monoclonal antibodies, i.e., anti-neuron-specific class III beta-tubulin isotype (TuJ1), anti-rat brain beta-tubulin, and anti-Leu-7 (HNK-1) antibodies. All the antibodies reacted with neurons. The carotid body anlage was first discerned at 6 days of incubation at the lateral portion of the third branchial artery. The cells and nerve fibers immunoreactive for TuJ1, brain beta-tubulin and Leu-7, which were connected with the distal ganglion of the vagus nerve, were found around the carotid body anlage at this stage. Within the carotid body anlage, no immunoreactivity yet appeared. The immunoreactive cells were accumulated around the carotid body anlage until 8 days of incubation. From 9 days of incubation, the immunoreactive cells continuing with the distal vagal ganglion began to enter into the carotid body anlage and also dispersed widely along the common carotid artery and its branches, giving rise to the glomus cells. At 12 days of incubation, a large portion of the carotid body was occupied by the immunoreactive cells. Thus, the present study evidences that the glomus cells in the carotid body and around the arteries are emigrés that arrive in each residential place from the distal vagal ganglion. Immunoreactivity for TuJ1, brain beta-tubulin, and Leu-7 in the glomus cells started to decrease at late stages of embryonic development. After hatching, no TuJ1-immunoreactive cells were detected in the carotid body region.

Animals↗
PubMed1994

Incidence of latent infection of Epstein-Barr virus in lung cancers--an analysis of EBER1 expression in lung cancers by in situ hybridization.

To evaluate the presence of Epstein-Barr virus (EBV) in lung cancers of Japanese patients, 81 lung cancers were examined using a highly sensitive in situ hybridization (ISH) method, employing an antisense oligonucleotide probe for EBV-encoded small nuclear RNA-1 (EBER). EBER1 expression was demonstrated in one poorly differentiated squamous cell carcinoma associated with marked lymphoid stroma (PDSCC-LS), two well differentiated adenocarcinomas, and two moderately differentiated squamous cell carcinomas, but was not detectable in other lung cancers, including small cell carcinomas. Unlike lymphoepithelioma-like undifferentiated carcinoma (LELC) of the lung, the PDSCC-LS consisted of poorly differentiated cells with distinct cell borders and nuclei with a coarse chromatin pattern and some prominent nucleoli. Most of the cancer cells expressed intense EBER1 signals. Although small to moderate numbers of cells positive for EBER1 were present in two adenocarcinomas and two squamous cell carcinomas, EBER1 signals varied in intensity and number in these four cases. Although polymerase chain reaction (PCR) and Southern blot hybridization with a 32P-labelled probe internal to the primers were conducted to detect the EBV genome in 24 lung cancers, including five EBER1-positive cases, the genome was found to be positive in the five cases with EBER1-positive staining, including the PDSCC-LS, two adenocarcinomas and two squamous cell carcinomas, but not in the other cases. This study indicates that the morphological features of EBV-associated lung cancers are not restricted to the typical LELC type.

Adenocarcinoma↗
PubMed1994

Colocalization of growth hormone (GH) and glycoprotein subunit alpha in GH-producing pituitary adenomas in acromegalic patients.

Thirty-one consecutive cases of pituitary adenoma in acromegalic patients were studied by immunohistochemistry. All adenomas contained cells immunoreactive with the anti-alpha-subunit of gonadotropic hormones (alpha; 0.6-53% of tumor cells) as well as with anti-growth hormone (GH; 4-74% of tumor cells). In serial section study, most cells immunoreactive with anti-alpha were identical to cells immunoreactive with anti-GH. There was a positive correlation between the percentages of cells immunoreactive for alpha in GH cells [alpha (%)/GH(%)] and those for prolactin (PRL) in immunoreactive tumor cells (PRL(%)/[PRL(%) + GH(%)]) in mixed GH cell-PRL cell adenomas, suggesting that the alpha-subunit may play a role in emergence of PRL cells.

Acromegaly↗
PubMed1994

Congenital euthyroid goitre with impaired thyroglobulin transport.

A case of congenital goitre with defective thyroglobulin (Tg) synthesis was studied from the clinical, biochemical and morphological perspectives. The patient, 5.5-year-old boy, who was clinically euthyroid, showed a positive perchlorate discharge test (37.2%). However, the iodination system seemed to be normal since radioiodine uptake into the thyroid was very high, and inspection of the H2O2-generating system using thyroid slices and an assay for peroxidase activity in microsomes showed no abnormalities. On the other hand, virtually no Tg was detected in the serum, and the amount of Tg in thyroid tissue, estimated with gel electrophoresis, was below 10% of the normal value, the quality of Tg being unchanged. Morphological observations demonstrated the presence of Tg in the markedly distended rough endoplasmic reticulum of the cytoplasm of follicular cells and a lack of Tg in the colloid of the follicular lumen. These results suggest that the thyroid is defective in Tg synthesis, probably associated with impaired transport of Tg from the cells to the lumen.

Child, Preschool↗
PubMed1994

Radiological study of symptomatic Rathke's cleft cysts.

We investigated the relationship between radiological findings and the nature of the cyst fluid and histological findings of six Rathke's cleft cysts. The results show that the majority (five of six cases) of symptomatic Rathke's cleft cysts exhibit no enlargement of the sella turcica on plain x-rays, which may be helpful in differentiating cystic pituitary adenoma in the radiological diagnostic process. Three cases with large cysts showing high-intensity T1-weighted magnetic resonance images harbored abundances of cholesterol crystal and hemosiderin pigment in the cyst walls. The high signal intensity in magnetic resonance images of Rathke's cleft cysts may be explained by hemorrhage and a deposition of cholesterol crystal and may be considered in certain cases of Rathke's cleft cyst, especially when they are large.

Adult↗
PubMed1993

Immunohistochemical localization of a neuron-specific beta-tubulin isotype in the developing chicken ultimobranchial glands.

The localization of a neuron-specific beta-tubulin isotype in the ultimobranchial glands from chickens at various stages of development was studied by means of light- and electron microscopic immunohistochemistry with a monoclonal antibody (TuJ1) against the beta-tubulin isotype, c beta 4. At 8 days of incubation, many C cells in the ultimobranchial glands showed immunoreactivity for TuJ1 invariable degrees, weak to intense. At 12 days of incubation, a vast majority of C cells were intensely immunoreactive for TuJ1, and further TuJ1-immunoreactive nerve fibers were distributed in the ultimobranchial glands. At 14 and 16 days of incubation, intense immunoreactivity for TuJ1 was sustained in the C cells. Electron microscopic analyses revealed that TuJ1 immunoreactivity was diffusely distributed throughout the cytoplasm and also localized on the secretory granules of C cells at these stages. TuJ1 immunoreactivity in the C cells started to decrease at late stages of embryonic development. At the hatching period, dense distributions of TuJ1-immunoreactive nerve fibers were observed in the ultimobranchial glands, whereas TuJ1 immunoreactivity of the C cells became very weak. In 10-day-old chickens, TuJ1 immunoreactivity was restricted to the nerve fibers.

Animals↗