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A Matsuno

Publications and source records attributed to A Matsuno.

At least 55 records · Page 3Linked to original sources
PubMed1998

An improved ultrastructural double-staining method for rat growth hormone and its mRNA using LR White resin: a technical note.

An improved new method for the simultaneous visualization of mRNA and encoded protein in LR White resin-embedded specimens is described. This pre-embedding electron microscopical in situ hybridization (procedure) localized rat growth hormone mRNA specifically as high electron-density products on the polysomes of the rough endoplasmic reticulum. A subsequent post-embedding immunoreaction, using protein A colloidal gold particles, identified growth hormone as gold particles both in the cisternae of the rough endoplasmic reticulum and on the secretory granules. In our previous report, we used Epon resin for tissue embedment, which required an etching process using hydrogen peroxide or sodium periodate for immunoreactivity retrieval. In general, osmification and embedment in Epon resin are reported to decrease the immunoreactivity of the targeted protein, and the etching process using hydrogen peroxide or sodium periodate results in deosmification and shades off the signals of mRNA. To resolve these problems, we have recently used LR White resin for tissue embedment. In LR White resin-embedded tissues, retrieval of immunoreactivity using hydrogen peroxide or sodium periodate is not required, and, therefore, the gradation of the signals of mRNA can be avoided.

Acrylic Resins↗
PubMed1998

Expression of Pit-1 mRNA and activin/inhibin subunits in clinically nonfunctioning pituitary adenomas. In situ hybridization and immunohistochemical analysis.

The pituitary-specific transcriptional factor Pit-1 is known to play a role in the development and differentiation of pituitary cells. Recent investigations have suggested a role for this transcriptional factor in pituitary adenomas, especially growth hormone (GH)- and prolactin (PRL)-secreting pituitary adenomas. In this study we analyzed the expression of Pit-1 mRNA and its protein in 24 clinically nonfunctioning pituitary adenomas in comparison with normal pituitary glands using in situ hybridization (ISH) and immunohistochemistry (IHC). The interaction between inhibin/activin, a member of the transforming growth factor-beta family, and Pit-1 was also studied. Immunohistochemically, Pit-1 protein was detected in 9 of 24 adenomas (37.5 %), and 8 of these 9 were also positive for the alpha subunit of glycoprotein (alphaSU). The expression of Pit-1 mRNA was detected in 14 of 24 (58.3%) clinically nonfunctioning adenomas, and it was found in all cases which expressed the Pit-1 protein. By the combined ISH and IHC method, Pit-1 mRNA was frequently observed in alphaSU-immunopositive cells in adenomas. The inhibin/activin alpha subunit was detected in all 24 adenomas and the betaA subunit was detected in 13 of 24 adenomas. The inhibin/activin betaA subunit was detected frequently with Pit-1 mRNA. From our observations, the inhibin/activin betaA subunit in nonfunctioning adenomas may have related the expression of Pit- mRNA in these adenomas.

Activins↗
PubMed1997

Application of confocal laser scanning microscopy (CLSM) to visualize prolactin (PRL) and PRL mRNA in the normal and estrogen-treated rat pituitary glands using non-fluorescent probes.

In the present study, we performed concomitant visualization of immunohistochemistry (IHC) and in situ hybridization (ISH) on the materials processed for conventional light microscopic specimens using non-fluorescent Confocal Laser. Scanning Microscopy (CLSM). CLSM was used in the reflection confocal mode using horseradish peroxidase (HRP)-3-3'diaminobenzidine (DAB)-osmium (osmium black) and nitroblue tetrazolium (NBT) as non-fluorescent detection methods (probes). To obtain clearer images of the organelles, images that were built up as electronic signals in CLSM were processed in an image analysis system (IAS). By using the combination of CLSM and IAS, in IHC, immunohistochemical localization of prolactin (PRL) was in well-developed lamellar or whorling rough endoplasmic reticula (RER), Golgi apparatus, and secretory granules. With ISH, the expression and distribution of PRL messenger ribonucleic acid (mRNA) was observed in a fashion suggesting polysome-like structures on RER. These observations were confirmed by immunoelectron microscopy and electron microscopic ISH. The herein-described method is expected to be useful to perform the concomitant observation of IHC and ISH at subcellular levels using the conventional light microscopic specimens.

Animals↗
PubMed1997

Proliferative activity and p53 protein accumulation correlate with early invasive trend, and apoptosis correlates with differentiation grade in oesophageal squamous cell carcinomas.

Using oesophageal squamous cell carcinoma samples of both intramucosal and advanced types, proliferative activity (Ki-67 labelling index), p53 protein accumulation and apoptosis (in situ DNA nick end labelling) were assessed, and the relation of these values to progression or differentiation grade of tumours was analysed. In terms of proliferative activity and the proportion of positive cases with p53 accumulation, a statistically significant difference was demonstrated between intraepithelial carcinomas and intramucosal carcinomas with stromal invasion (17.2% vs 31.7% for the Ki-67 labelling index, and 23.5% vs 67.4% for the proportion of positive cases of p53 accumulation). Values for the latter were almost comparable to those of advanced carcinomas. Immunohistologically, Ki-67 positive, proliferating cells were distributed preferentially in the peripheral fronts of invading nests. Apoptotic cells were observed in the inner areas of the invading nests of the intramucosal carcinomas with stromal invasion and in more advanced lesions, but were rarely observed in the normal epithelium or intraepithelial carcinomas. Apoptotic cells were seen mainly around areas of keratinization, and the apoptotic cell index was higher in well and moderately differentiated types of advanced carcinomas than in the poorly differentiated type (2.59% vs 1.09%). An increase in proliferative activity and an accumulation of p53 protein are associated with the onset of early carcinomatous invasion, while apoptosis is closely linked with the differentiation grade of carcinoma cells.

Antibodies, Monoclonal↗
PubMed1997

Expression of the cyclin dependent kinase inhibitor p21WAF1/CIP1 in oesophageal squamous cell carcinomas.

To elucidate the role of CDK inhibitor p21WAF1/CIP1 in human oesophageal squamous cell carcinomas, we examined its expression immunohistochemically using surgically resected tissues from 25 patients, and have analyzed the relationship with alteration of p53 gene (F-SSCP analysis), proliferative activity (Ki-67 labelling index), frequency of apoptosis (in situ DNA nick end labelling), and degree of differentiation. P21 expression was observed in 11 cases (44%) with a percentage of positive cells ranging between 1% and 10%. Of the 25 cases, 4 cases showed > 5% of positive cells. As for the relationship with p53 gene, all 7 p53-mutation positive cases were negative for p21 expression, whereas 11 out of 18 mutation negative cases showed positive for p21 expression. As for the relationship with degree of tumour differentiation, 6 out of 8 well differentiated type cases showed positive for p21 expression. By contrast, all 8 cases of poorly differentiated type were negative for p21 expression. Frequency of apoptotic cells was significantly higher in p21 positive cases than negative cases although Ki-67 labelling index was almost the same regardless of the expression of p21. P21 expressing cells were distributed mainly in the middle layers of the invading nests, especially around the keratinization, which was almost similar to the distribution of apoptotic cells. Our results suggest that expression of p21 in human oesophageal squamous cell carcinomas is induced by a p53-dependent pathway and affects apoptosis and differentiation of carcinoma cells.

Adult↗
PubMed1997

Immunohistochemical examination of proliferative potentials and the expression of cell cycle-related proteins of intracranial chordomas.

The difference in biological features between recurrent and nonrecurrent intracranial chordomas has not been studied. In this study, proliferative potentials of chordomas were studied with an immunohistochemical staining method, mainly using anti-Ki-67 antibody, MIB-1, which is known to be available for archival paraffin sections, together with immunohistochemical studies on the expression of cell cycle or apoptosis-related proteins, including p53, cyclin D1, and bcl-2 proteins. The correlation among MIB-1 staining indices, the immunoreactivities of these proteins, and clinical courses of intracranial chordomas were analyzed retrospectively, and the statistically significant correlation between MIB-1 staining index (SI) and recurrence has been clarified. The mean MIB-1 SI of recurrent tumors was 10.2%, being shown to be higher than that of nonrecurrent tumors (2.8%). The immunohistochemically positive staining of cell cycle-related protein, especially p53 and cyclin D1 proteins, correlated well with recurrence and high MIB-1 SI. In conclusion, both the examination of proliferative potentials of chordomas using MIB-1 SI and the study of the immunoreactivity of p53 and cyclin D1 proteins are important for their biological and histopathological analyses and the prediction of future recurrence.

Adolescent↗
PubMed1997

A rare case of hamartoma in the lateral ventricle: case report.

BACKGROUND: Intraventricular manifestation of a hamartoma is an unusual clinical entity. CASE DESCRIPTION: A 12-year-old girl was admitted with complaints of dizziness and head heaviness. Computed tomography and T1-weighted magnetic resonance imaging (MRI) demonstrated an isodensity or isointensity mass lesion with cystic component in the right lateral ventricle, which showed relatively high signal intensity on T2-weighted MRI and lacked contrast enhancement. Histopathologic examination on the surgically removed specimens using glial fibrillary acidic protein, Klüver-Barrera, Bodian stainings, bromouridine labeling index, and MIB-1 immunohistochemical staining confirmed that the tumor had glial and neuronal components and low proliferative potentiality. CONCLUSION: This case is the first report of intraventricular hamartoma, although some reports on intracranial hamartoma located in areas other than the hypothalamus have been published. The radiologic findings, including relatively high signal intensity on T2-weighted MRI and absence of contrast enhancement, may be suggestive of the diagnosis of intraventricular hamartoma; however, the specific stainings for glial and neuronal cells and proliferative evaluation are essential to the precise diagnosis of hamartoma. Clinical manifestation of hamartoma in the ventricular system, though rare, should be kept in mind.

Brain Diseases↗
PubMed1997

Proliferative activity of central neurocytoma: measurement of tumor volume doubling time, MIB-1 staining index and bromodeoxyuridine labeling index.

Central neurocytoma is considered to be a benign intracranial neoplasm, but little is known about the biological behavior of this type of tumor. Proliferative activity of central neurocytoma was measured in 10 cases using MIB-1 staining for Ki-67 antigen. The MIB-1 staining value varied from < 0.1% to 5.6%, to indicating that some of these tumors have proliferative potential similar to that of anaplastic astrocytoma or malignant meningioma. The bromodeoxyuridine labeling index (BUdR LI, BrdU LI) was measured in 2 cases and the results correlated well with those of the MIB-1 analysis. Tumor volume doubling time (Td) measured in one case was 358 days which is similar to that of malignant meningioma. In one case, the MIB-1 value taken before and after 58 Gy of radiation treatment decreased markedly from 5.6% to 0.2%. The other 9 cases were also treated by radiation therapy (50-60 Gy) and no tumor recurrence was observed during follow-up periods ranging from 23 to 160 months. Another two patients with partially removed and 3 with subtotally removed tumors showing relatively high MIB-1 values might also have benefited from radiation therapy.

Adult↗
PubMed1997

Modulation of protein kinases and microtubule-associated proteins and changes in ultrastructure in female rat pituitary cells: effects of estrogen and bromocriptine.

This study focused on the intracellular signal transduction system and microtubule-associated proteins (MAPs), such as MAP-2 and Tau protein. The modulation of these proteins and their correlation with ultrastructural changes were investigated in rat pituitary prolactin (PRL) cells. Adult female Wistar rats were treated with estrogen and bromocriptine and their pituitary glands were removed for analysis of the expression of tubulin, MAP-2, Tau protein, protein kinase C (PKC), and calcium calmodulin (CaM) kinase. Western blot analysis showed that estrogen increased and bromocriptine decreased the expression of PKC alpha, beta 1, beta 2, CaM kinase alpha, beta, MAP-2, and Tau protein. MAP-2 and Tau protein, which are cytosolic proteins, being translated on free ribosomes, were associated with the membrane of whirling rough endoplasmic reticulum (RER) in estrogen-treated cells and dissociated with vesiculated RER induced by bromocriptine. These results suggested that the modulation of MAP-2 and Tau protein may reflect changes of PKC and CaM kinase, and that the quantitative changes and intracellular modulation of MAPs induced by estrogen and bromocriptine, i.e., estrogen-induced association and bromocriptine-induced dissociation of MAP-2 and Tau protein with membrane of RER, may reflect the dynamics of microtubules and are associated with structural changes in the RER and changes in the synthesis and intracellular transport of PRL.

Animals↗
PubMed1997

Foot structure and foot protein in the cross striated muscle of a pecten.

The foot-like structure of pecten (mollusk) cross striated muscle cells was studied from structural and biochemical standpoints, and compared with foot structures of vertebrate skeletal muscle cells. In vertebrate muscles, foot structures have been observed at the interspace between T-tubules and sarcoplasmic reticula (SR). In pecten muscles, T-tubules were not observed, but SR were found situated in the outer portions of the cell contacting the cell membrane, and foot-like structures were recognized at the interspace between the SR and cell membrane. We could isolate the SR fraction from these muscles in which vesicles of SR/cell membranes were included. In the SR fraction, foot-like structures were observed ultrastructurally by thin sectioning. The size and shape of the foot-like structure, whether observed in intact cells or SR fractions, appear smaller than foot structures of vertebrates. However, when calculated by SDS-PAGE, the molecular weight of the structure is similar to that of vertebrates. These findings are discussed and compared to characteristics of foot structures and foot proteins of vertebrate skeletal muscles reported in previous studies.

Animals↗
PubMed1997

[Airway difficulty associated with multiple teratisms of the oral cavity in a newborn infant].

A 13-day-old infant with multiple teratisms of the oral cavity was scheduled for resection of the epignathus. Her oral cavity was occupied by large epignathus, submandibular tumor, congenital bifid tongue and cleft palate, but she had no other congenital abnormalities. We anticipated that an endotracheal intubation would be difficult because of the large size of the tumor in relation to the oral cavity. Initially, awake intubation using a standard laryngoscope was attempted. Although a large elastic epignathus did not interrupt the insertion of the curved laryngoscope blade, the hard submandibular tumors protruded from the submaxillary ramport interfered with mid-line management of the laryngoscope. After several attempts of intubation, a better exposure was obtained and she was successfully intubated using a stylet under deep sedation. We recognized that a careful observation of anatomical abnormalities in the oral cavity is important to keep airway in an infant with multiple abnormalities of the oral cavity.

Abnormalities, Multiple↗
PubMed1996

Sequence analysis of the genome of the unicellular cyanobacterium Synechocystis sp. strain PCC6803. II. Sequence determination of the entire genome and assignment of potential protein-coding regions.

The sequence determination of the entire genome of the Synechocystis sp. strain PCC6803 was completed. The total length of the genome finally confirmed was 3,573,470 bp, including the previously reported sequence of 1,003,450 bp from map position 64% to 92% of the genome. The entire sequence was assembled from the sequences of the physical map-based contigs of cosmid clones and of lambda clones and long PCR products which were used for gap-filling. The accuracy of the sequence was guaranteed by analysis of both strands of DNA through the entire genome. The authenticity of the assembled sequence was supported by restriction analysis of long PCR products, which were directly amplified from the genomic DNA using the assembled sequence data. To predict the potential protein-coding regions, analysis of open reading frames (ORFs), analysis by the GeneMark program and similarity search to databases were performed. As a result, a total of 3,168 potential protein genes were assigned on the genome, in which 145 (4.6%) were identical to reported genes and 1,257 (39.6%) and 340 (10.8%) showed similarity to reported and hypothetical genes, respectively. The remaining 1,426 (45.0%) had no apparent similarity to any genes in databases. Among the potential protein genes assigned, 128 were related to the genes participating in photosynthetic reactions. The sum of the sequences coding for potential protein genes occupies 87% of the genome length. By adding rRNA and tRNA genes, therefore, the genome has a very compact arrangement of protein- and RNA-coding regions. A notable feature on the gene organization of the genome was that 99 ORFs, which showed similarity to transposase genes and could be classified into 6 groups, were found spread all over the genome, and at least 26 of them appeared to remain intact. The result implies that rearrangement of the genome occurred frequently during and after establishment of this species.

Bacterial Proteins↗
PubMed1996

A case of pituitary somatotroph adenoma with concomitant secretion of growth hormone, prolactin, and adrenocorticotropic hormone--an adenoma derived from primordial stem cell, studied by immunohistochemistry, in situ hybridization, and cell culture.

Somatotroph adenomas often secrete prolactin (PRL) besides growth hormone (GH) and are sometimes immunostained for other anterior pituitary hormones or their subunits, such as thyroid-stimulating hormone (TSH) beta-subunit and glycoprotein hormone alpha-subunit (alpha SU). However, somatotroph adenomas showing hypersecretion of adrenocorticotropic hormone (ACTH) are extremely rare. There have been, to our knowledge, only five published reports on somatotroph adenomas accompanied by excessive ACTH secretion. Here we report a case of intracavernously invading somatotroph macro-adenoma with high serum GH, PRL, and ACTH levels. We examined the case using immunohistochemistry (IHC), in situ hybridization (ISH), and cell culture, and confirmed GH, PRL, and ACTH, as well as alpha SU, production, and the expression of Pit-1 protein by the adenoma, which is known as a transcriptional factor for GH, PRL, and TSH, not for ACTH. Therefore, the presence of unknown transcriptional factor other than Pit-1, common to GH, PRL, and ACTH, may be speculated to be expressed in this adenoma. In our previous study, we had found plurihormonal mRNA expression, especially for ACTH, the beta-subunit of follicle-stimulating hormone and luteinizing hormone in some somatotroph adenomas, using non-radio-isotopic ISH, and suggested that these adenomas might be derived from plurihormonal primordial stem cells. Our present case is significant from the viewpoint of histogenesis of pituitary adenomas, because it further supports the cell origin of somatotroph adenomas from plurihormonal primordial stem cells, and moreover it suggests the presence of unknown transcriptional factor other than Pit-1, common to GH, PRL, and ACTH.

Adenoma↗
PubMed1996

Simultaneous ultrastructural identification of growth hormone and its messenger ribonucleic acid using combined immunohistochemistry and non-radioisotopic in situ hybridization: a technical note.

The present electron microscopical study is concerned with the simultaneous visualization of messenger ribonucleic acid (mRNA) and its encoded protein in the same specimen. Pre-embedding electron microscopical in situ hybridization (EM-ISH) on rat pituitary gland tissue localized growth hormone mRNA in the polysomes of the rough endoplasmic reticulum, and subsequent postembedding immunolabelling using protein A-colloidal gold particles identified growth hormone mainly in the secretory granules. We believe that our report provides the first simultaneous ultrastructural identification of mRNA and its encoded protein using combined pre-embedding EM-ISH and immunohistochemistry. In this method, the signals for mRNA were localized specifically as highly electron dense products on the polysomes of the endoplasmic reticulum, and those for its encoded protein were recognized as gold particles both in the cisternae of the reticulum and in the secretory granules. Our ultrastructural double labelling method for mRNA and protein may provide a tool to find important clues for elucidating the intracellular correlation of mRNA translation and secretion of translated protein, because of its high resolution, good morphological preservation, and the specific localization of the reaction products.

Animals↗
PubMed1996

In situ hybridization analysis of Pit-1 mRNA and hormonal production in human pituitary adenomas.

The pituitary-specific transcriptional factor, Pit-1, is a member of the POU-domain family which has a role in the development and differentiation of three pituitary cell types: somatotrophs, lactotrophs, and thyrotrophs. Recent investigations have suggested the involvement of specific regulation of Pit-1 transcripts in human pituitary adenomas. In this study, we analyzed the expression of Pit-1 gene and Pit-1 product in various human pituitary adenomas using in situ hybridization (ISH) and immunohistochemistry (IHC). Northern hybridization analysis revealed 2.4- and 4.1-kb Pit-1 transcripts in normal pituitary, growth hormone (GH)-, prolactin (PRL)- and thyrotropin (TSH)-secreting adenomas. By ISH analysis, Pit-1 mRNA was detected in 42 (84%) of 50 adenomas. The highest incidence was observed in 15 GH-secreting adenomas and 8 TSH-secreting adenomas, in which Pit-1 mRNA was detected in all cases. Pit-1 mRNA expression was detected in 11 (85%) of 13 PRL-secreting adenomas. In 12 clinically non-functioning adenomas, Pit-1 mRNA was also present in 8 cases, and 5 of these were associated with immunohistochemical expression of Pit-1 product. By combined ISH and IHC, Pit-1 mRNA was often colocalized with GH, PRL or TSH beta immunoreactivities and sometimes colocalized with alpha-subunit of glycoprotein (alpha SU) immunoreactivity. The expression of Pit-1 mRNA in various cell types of human pituitary adenomas in addition to GH, TSH beta and PRL immunoreactivities suggests that Pit-1 may play a role in functional development of pituitary adenomas, including clinically non-functioning adenomas. However, some additional transcriptional factors or enhancers may be required.

Adenoma↗