Biomedical subjects

A Matsuno

Publications and source records attributed to A Matsuno.

At least 73 records · Page 4Linked to original sources

PubMed1996

Clinical and histopathological analysis of proliferative potentials of recurrent and non-recurrent meningiomas.

Proliferative potentials of meningiomas from 127 patients were examined immunohistochemically using the anti-Ki-67 monoclonal antibody, MIB-1, on paraffin sections, and the correlation among MIB-1 staining index (SI), histopathological finding, and clinical course of the disease was analyzed retrospectively. The mean MIB-1 SI of 50 male patients with meningioma was 5.5%, whereas that of 77 female patients was 2.7%. Higher MIB-1 SI were observed for younger patients. These age- and sex-related differences in MIB-1 SI were statistically significant. The patients were assigned to one of three groups: those with non-recurrent meningioma (n = 73); those with recurrent meningioma in whom the specimens obtained during the initial surgery were used to calculate the MIB-1 SI (n = 21); and those with recurrent meningioma for whom the specimens obtained during the surgery for recurrent tumors were used to calculate the MIB-1 SI (n = 33). The mean MIB-1 SI in these patients were 1.6%, 3.6%, and 8.8%, respectively, and there were statistically significant differences among these three groups. Statistical analyses reveal that meningiomas with a MIB-1 SI of 3% or more have a significantly high tendency for recurrence during the clinical courses, especially within the first 10-year follow-up periods. Moreover, there is statistically significant correlation between MIB-1 SI and recurrence in each Simpson's grade. The time interval to the next recurrence for recurrent meningiomas is associated with the proliferative potential represented by the MIB-1 SI, and a correlation equation has been proposed to predict the date of the next recurrence. Analyses on cellularity of meningiomas revealed no statistically significant difference in cellularity between non-recurrent and recurrent meningiomas. There was no statistically significant relationship between cellularity and MIB-1 SI of meningiomas. In conclusion, examination on proliferative potentials of meningiomas using MIB-1 SI is very important for biological and histopathological analyses and the prediction of future recurrence.

Adult↗

PubMed1996

Ultrastructural studies on paramyosin core filaments from native thick filaments in catch muscles.

Catch muscles of molluscs usually have thick filaments of about 100 nm in diameter. The filament is constructed of a paramyosin core filament and an outer layer of myosin molecules. Myosin molecules are situated on the paramyosin core filament towards both ends, and they consequently have polarity towards both ends. According to our observations on the paramyosin core filaments from the native thick filaments, they bear regular cross-striations on their surfaces of about 14.5 nm periodicity when incubated in a KCl solution for a short time. The periodic pattern is supposed to be representative of peculiar arrangements of paramyosin molecules in the core, but the periodic pattern disappeared during incubation in a solution of high concentration KCl for a prolonged time, and a 'Bear-Selby net' pattern appeared substitutionally. These 'Bear-Selby net' patterns were conveniently divided into 3 types among 4 paramyosin core filaments from 4 'catch' muscles; the adductors of a pecten, an oyster and a clam, and the byssus retractor of a mussel. The 'Bear-Selby net' of an oyster resembled that of a pecten. Purified paramyosin crystals from the 4 muscles showed a common periodicity of about 72.5 nm. Electrophoresis with SDS of the 4 paramyosins on 6% polyacrylamide gels revealed molecular weights at 104 kD from a pecten, 105 kD from an oyster, 103 kD from a clam and 105 kD from a mussel.

Actin Cytoskeleton↗

PubMed1996

Correlation between MIB-1 staining index and the immunoreactivity of p53 protein in recurrent and non-recurrent meningiomas.

Wild type p53 protein has been shown by recent investigations to be involved in the negative regulation of cell proliferation, whereas aberrant p53 protein has lost this negative regulation of cell growth. Wild type p53 protein, which has a very short half-life, has generally been considered to be undetectable using immunohistochemical methods; however, according to a recent report, wild type p53 protein may accumulate in the nuclei because of a defective ubiquitin pathway. Aberrant p53 protein has a longer half-life, and thus is visible using immunohistochemical methods. In this study, both the proliferative potential represented by the MIB-1 staining index (SI) and the immunoreactivity of p53 protein in 51 intracranial meningiomas were studied applying immunohistochemical staining methods to archival paraffin sections. The correlation among MIB-1 SI, p53 immunoreactivity, histopathologic findings and the clinical course of the meningiomas was also analyzed retrospectively. Although it is not possible with available reagents to distinguish between aberrant p53 protein and wild type p53 protein, statistical analyses show that p53 protein was immunostained both in meningiomas with high MIB-1 SI and in recurrent meningiomas. This demonstrates the close relationship among p53 immunoreactivity, MIB-1 SI, and recurrence; therefore, the presence of p53 protein by immunohistochemical examination may suggest the proliferative activity of meningioma and is capable of serving as a predictor of future recurrence.

Antibodies, Monoclonal↗

PubMed1996

Combined non-isotopic in situ hybridisation and indirect immunohistochemical analysis of hormone production in the rat pituitary gland.

An understanding of the intracellular relation between hormonal expression (storage) and gene expression (production) is essential for elucidating the functional status of the individual cells in endocrine tissue such as the pituitary gland. To this end, mRNA expression was visualised by using a combined in situ hybridisation and immunohistochemistry method in routinely processed, formalin fixed, paraffin wax embedded rat pituitaries. mRNA was detected by non-isotopic in situ hybridisation (alkaline phosphatase antialkaline phosphatase method, with nitroblue tetrazolium and 5-bromo-4-chloro-3-indolylphosphate as substrates). Sections were then stained by using the immunoperoxidase method to demonstrate pituitary hormone expression. The specificity of the combined staining method was confirmed by staining adjacent sections separately. The antigenicity of rat growth hormone and prolactin was adequately preserved following hybridisation. In conclusion, this method is specific, easy to use and permits the determination of the functional status of individual cells.

Journal Article↗

PubMed1996

Expression of human Pit-1 product in the human pituitary and pituitary adenomas. Immunohistochemical studies using an antibody against synthetic human Pit-1 product.

OBJECTIVE: Pit-1, a member of a family of the POU-domain DNA binding factors, has been known as a pituitary-specific transcriptional factor that regulates functional differentiation toward somatotrophs, lactotrophs, and thyrotrophs in the rodent pituitary gland. The aim of this study is to elucidate the role of human Pit-1 (hPit-1) protein in the differentiation of human pituitary adenomas, using immunohistochemistry. DESIGN: Anti-human Pit-1 polyclonal antibody against synthetic peptide was applied to perform the avidin-biotinperoxidase complex method on paraffin sections of 75 surgically obtained pituitary adenomas and 12 nontumorous human pituitaries obtained at autopsy. RESULTS: In normal human pituitary glands, many cells were positive for hPit-1 product in the nuclei of somatotrophs, lactotrophs, and somatomammotrophs. Among 75 pituitary adenomas, hPit-1 product was expressed in 55 adenomas (73.3%). All (100%) of the growth hormone-positive and thyrotroph cell adenomas were positive for hPit-1 product. Unexpectedly, expression of hPit-1 was found in a limited number of adrenocorticotropic hormone-producing adenomas and clinically nonfunctioning adenomas, including gonadotroph cell adenomas, although localization was found only in occasional cells. CONCLUSIONS: The invariable expression of hPit-1 protein in growth hormone-positive adenomas and thyroid-stimulating hormone-positive adenomas may suggest the role of Pit-1 protein in specific differentiation of the adenoma cells. The expression of hPit-1 in various other types of adenomas may indicate the involvement of other unidentified transcription factors or specific mediators that have roles in these differentiations. Our observation may provide some insight into the origin of cell types of some clinically nonfunctional adenomas.

Adenoma↗

PubMed1996

Expression of Pit-1 and estrogen receptor messenger RNA in prolactin-producing 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. Recently, specific DNA-dependent interactions have been observed between Pit-1 and nuclear receptors, including: thyroid hormone receptor; retinoic acid receptor; glucocorticoid receptor; and estrogen receptor (ER). The cooperative interaction between Pit-1 and ER required for prolactin enhancer activity in rat pituitaries has been suggested. We analyzed the expression of Pit-1 messenger ribonucleic acid (mRNA) and ER mRNA in 15 human prolactin-producing adenomas using nonradioisotopic in situ hybridization. Their products were also studied by immunohistochemical analysis. Pit-1 mRNA was detected in 12 (80%) of 15 prolactin-producing adenomas. On the other hand, ER mRNA was detected in 14 (94%) of adenomas studied. mRNAs of Pit-1 and ER were detected more frequently than immunohistochemical expression of their products. By combined in situ hybridization and immunohistochemical examination, Pit-1 mRNA and ER mRNA were often colocalized with prolactin immunoreactivities. The colocalizations of Pit-1 mRNA and ER protein were observed in adenoma cells. The high incidence of the expression of ER mRNA in prolactin-producing adenomas may suggest cooperative interactions between Pit-1 and ER in functional differentiation and development of prolactin-producing adenomas.

Adolescent↗

PubMed1995

Changes in the ultrastructural distribution of prolactin and growth hormone mRNAs in pituitary cells of female rats after estrogen and bromocriptine treatment, studied using in situ hybridization with biotinylated oligonucleotide probes.

The expression and distribution of prolactin (PRL) mRNA and their alterations induced by estrogen and bromocriptine were investigated using non-radioisotopic in situ hybridization (ISH) at the electron microscopic (EM) level. Our EM-ISH studies using biotinylated oligonucleotide probes showed that estrogen induced whirling changes of the rough endoplasmic reticulum (RER) of female rat PRL cells and increased transcription of PRL genes located on the polysomes of the whirling RER. The presence of mammosomatotroph cells in the rat pituitary gland was also verified in our EM-ISH studies. After bromocriptine administration, PRL cells contained many secretory granules due to the inhibition of secretion. Pre- and post-embedding EM-ISH and northern hybridization studies revealed that bromocriptine induced the distorted, vesiculated, and dilated RER, and also the suppressed PRL mRNA expression. The activity of protein kinase C (PKC), which mediates PRL gene expression, tended to be elevated by estrogen and suppressed by bromocriptine. Therefore, it is considered that the ultrastructural and quantitative changes in PRL mRNA expression evoked by estrogen and bromocriptine may be mediated by the intracellular signal transduction system, including PKC.

Animals↗

PubMed1995

Expression of plurihormonal mRNAs in somatotrophic adenomas detected using a nonisotopic in situ hybridization method: comparison with lactotrophic adenomas.

We used a nonisotopic in situ hybridization (ISH) method to investigate the expression of pituitary hormone, including glycoprotein hormone mRNAs in 17 somatotrophic and four lactotrophic adenomas. Our ISH studies of lactotrophic adenomas showed that their hormonal gene expression was confined to prolactin, whereas those of somatotrophic adenomas showed that some of them expressed plurihormonal genes. In some somatotrophic adenomas that were immunohistochemically negative for pituitary hormones, positive reactions, mainly for adrenocorticotropic hormone (ACTH), follicle-stimulating hormone beta subunit (FSH beta), and luteinizing hormone beta subunit (LH beta) mRNAs, were observed in our ISH studies. These results suggest that some somatotrophic adenomas may originate from plurihormonal primordial stem cells, which we have presumed serve as precursors for various hormone-expressing cells. It is unclear why some somatotrophic adenomas derived from plurihormonal primordial stem cells manifest clinically only as the acromegalic hyperfunction syndrome or gigantism. Additional translational factors or some other somatic mutations may play important roles in the clinical manifestations of such adenomas. In conclusion, some somatotrophic adenomas appear to be derived from plurihormonal primordial stem cells, whereas lactotrophic adenomas are well differentiated tumors that originate from lactotrophic cells, which represent the final stage of acidophilic cell line differentiation.

Adenoma↗

PubMed1995

GH and PRL gene expression by nonradioisotopic in situ hybridization in TSH-secreting pituitary adenomas.

TSH-secreting pituitary adenomas are rare. The transcriptional expression (messenger ribonucleic acids: mRNAs) of TSH beta, GH, and PRL in five patients with TSH-secreting pituitary adenoma was studied by the in situ hybridization (ISH) method in order to elucidate their multiple hormone production. These patients showed inappropriately elevated serum TSH and alpha-subunit levels as well as pituitary mass lesions. The tissues from pituitary adenomas were obtained at the time of transsphenoidal surgery and revealed immunohistochemically the expression of alpha-subunit and TSH beta in all patients. Four adenomas were immunohistochemically associated with GH or PRL localization. The presence of pituitary-specific transcriptional factor Pit-1 was demonstrated in all adenomas in the nuclei of many cells. By ISH, signals for TSH beta mRNA were present in all five cases in many adenoma cells. Expression of GH mRNA and PRL mRNA were detected not only in four adenomas in which both hormonal products were immunolocalized but also in one adenoma that was immunohistochemically negative for GH and PRL. Combined staining by ISH and immunohistochemistry revealed the expression of GH mRNA and PRL mRNA in TSH beta-immunoreactive cells. Our findings indicate that TSH-secreting adenomas are multihormone-producing and could arise from precursor or stem cells rather than from differentiated TSH-secreting cells. It is suggested that ISH combined with immunohistochemistry may provide additional detailed information concerning the multidirectional histogenesis of this rare type of adenoma.

Adenoma↗

PubMed1995

Transcavernous surgery; an effective treatment for pituitary macroadenomas.

The endocrinological outcome in four patients with pituitary macroadenomas laterally invading the cavernous sinus, who were treated surgically by the transcranial transcavernous approach, was compared with that in four patients with macroadenomas that had been removed transsphenoidally. The decrease in the elevated serum levels of anterior pituitary hormones after transcavernous surgery ranged from 58.4% to 90.1%, whereas after transsphenoidal surgery it ranged from 0% to 46.1%. The responsiveness of pituitary hormones to stimulation tests was restored and maintained after transcranial transcavernous surgery. Transsphenoidal surgery achieved neither sufficient tumor reduction nor produced a satisfactory endocrinological remission. When cavernous sinus invasion is suspected by magnetic resonance imaging, even if it cannot be confirmed with certainty, transcranial transcavernous surgery is recommended. It is a useful surgical procedure for obtaining a sufficient degree of tumor extirpation and satisfactory endocrinological improvement in patients with macroadenomas laterally invading the cavernous sinus, particularly somatotroph or corticotroph macroadenomas. Postoperatively, mild cranial nerve paresis may occur, but this may resolve in 1-4 months.

Adenoma↗

PubMed1994

Ultrastructural distribution of growth hormone and prolactin mRNAs in normal rat pituitary cells: a comparison between preembedding and postembedding methods.

In situ hybridization (ISH) at the electron microscopic level is essential for elucidating the intracellular distribution and role of mRNA in protein synthesis. We describe our electron microscopic ISH method using biotinylated oligonucleotide probes for rat growth hormone and prolactin mRNAs and compare the preembedding method with the postembedding method. Preembedding electron microscopic ISH localized rat growth hormone and prolactin mRNAs on the polysomes of the rough endoplasmic reticulum (RER). Rat growth hormone mRNA was distributed diffusely on the RER, whereas rat prolactin mRNA was scattered and distributed focally. Thus there might be a specific translational site for prolactin mRNA on the RER. Rat growth hormone mRNA signals were also recognized on the polysomes of the RER, using the postembedding method with streptavidin gold conjugate. The hybridization signal intensity using the postembedding method was lower, and non-specific signals were more frequent, in comparison with the preembedding method. The preembedding method thus appears to be easier and better than the postembedding method from the viewpoint of utility and preservation of mRNA. Electron microscopic ISH is considered to be an important tool for evaluating the intracellular localization of mRNA and the site of specific hormone synthesis on the RER.

Animals↗

PubMed1994

Systemic cytomegalovirus infection during postoperative chemoradiotherapy for malignant astrocytoma: case report with immunohistochemistry and in situ hybridization.

We report a patient with a systemic cytomegalovirus (CMV) infection, which occurred during postoperative chemoradiotherapy for a malignant astrocytoma. To our knowledge, there is no report that is especially focused on the association with a CMV infection. Interstitial pneumonia and gastrointestinal bleeding, which developed suddenly during postoperative chemoradiotherapy, resulted in the patient's death. A histopathological examination of the postmortem specimens revealed numerous "owl's eye" cells containing intranuclear inclusion bodies, which were identified as CMV by immunohistochemical examination and in situ hybridization. The premortem diagnosis of CMV infection is usually difficult, because an anti-CMV titer can be nonspecifically elevated. With immunohistochemical examination and in situ hybridization, CMV in excretory or biopsy specimens can be identified and the diagnosis of CMV infection can be established. When serious pneumonia or massive gastrointestinal bleeding occurs during postoperative chemoradiotherapy, the differential diagnosis should include the possibility of CMV infection and we recommend an immunohistochemical examination and in situ hybridization for the detection of CMV.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1994

Gigantism in sibling unrelated to multiple endocrine neoplasia: case report.

The cases of gigantism sisters with somatotroph adenomas unrelated to multiple endocrine neoplasia (MEN) Type 1 are reported. The sisters grew rapidly since they were 5 or 6 years old and were diagnosed to have gigantism with pituitary adenoma by computed tomographic scan and magnetic resonance imaging. A serum endocrinological examination showed the elevated growth hormone values. After thyroxine-releasing hormone stimulation, growth hormone values exhibited a paradoxical rise. They were supposed to be unrelated to MEN Type 1, because analysis of the 11th chromosomes and the other endocrine functions were normal. They were operated on by the transphenoidal method. Immunohistochemical staining of both tumor specimens confirmed somatotroph adenomas. Pituitary adenoma associated with MEN Type 1 is a well-recognized entity. However, the sporadic occurrence of pituitary adenoma unrelated to MEN Type 1, especially in siblings, is extremely rare. Fifteen cases of pituitary adenomas in siblings were described in the literature. As for gigantism, only two brothers were reported. Our case of gigantism sisters is the second sporadic case. In our review of the isolated cases of pituitary adenoma in siblings described in the literature, 12 (70%) of 17 cases including ours are acromegaly or gigantism. This incidence is much higher than that of MEN Type 1 patients with pituitary adenomas. The cause of the familial occurrence of pituitary adenomas is still unclear, although autosomal recessive inheritance has been suggested. It has been stated that point mutations in codon 201 or 227 of the Gs alpha gene located in chromosome 20 were found in about 35 to 40% of somatotroph adenomas.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗

PubMed1994

Application of biotinylated oligonucleotide probes to the detection of pituitary hormone mRNA using northern blot analysis, in situ hybridization at the light- and electron-microscope levels.

There have been many reports on radioisotopic in situ hybridization (ISH) studies for the demonstration of pituitary hormone mRNAs in normal pituitary gland and pituitary adenomas. Recent studies have revealed that non-radioisotopic ISH has several advantages over the radioisotopic method. Using ISH with biotinylated oligonucleotide probes, we have been able to localize various pituitary hormone mRNAs in paraffin wax or frozen sections of rat normal pituitary gland and human pituitary adenomas. For control studies we used ISH with sense probes, ISH without probes, pretreatment with ribonuclease, ISH with a probe for beta-actin and Northern blot hybridization. Using biotinylated probes, gene transcripts of rat growth hormone and prolactin were detected by Northern blot hybridization. The same biotinylated probes were used not for light microscope ISH but also for the electron microscopical demonstration of rat growth hormone and prolactin mRNAs on the polysomes of the rough endoplasmic reticula. It is emphasized that biotinylated oligonucleotide probes are useful for the analysis of pituitary endocrine function because they are applicable to the three hybridization methods, namely, Northern blot hybridization and ISH at the light and electron microscope levels.

Adenoma↗

PubMed1994

Clinical and immunohistochemical studies on TSH-secreting pituitary adenoma: its multihormonality and expression of Pit-1.

Eight patients with thyrotropin (TSH)-secreting pituitary adenoma are described. Serum TSH levels were inappropriately elevated in spite of elevated thyroid hormones. The serum-free glycoprotein alpha-subunit level was elevated in all the patients. The alpha-subunit to TSH molar ratio, a "tumor marker" for TSH-secreting adenoma, ranged from 1.06 to 6.16. All patients had macroadenoma and underwent transsphenoidal surgery. Light-microscopic indirect immunoperoxidase method applied on formalin-fixed paraffin-embedded specimens revealed alpha-subunit and TSH beta immunoreactivity in all adenomas. The proportion of TSH beta-positive cells ranged from 20% to 75% of adenoma cells. Six adenomas (75%) were associated with growth hormone (GH) and/or prolactine (PRL) immunoreactivity. By the double staining method, TSH beta and the alpha-subunit were frequently colocalized in the same cells, but some cells were found to contain either alpha-subunit or TSH beta. We also analyzed the localization of a pituitary-specific transcriptional factor, Pit-1, which has been suggested to play a role in functional differentiation toward growth hormone, prolactine, and TSH. All cases were positive for Pit-1 product using antibody against human Pit-1 synthesized peptide. Pit-1 product was localized in the nuclei of many adenoma cells and was frequently identified in cells that were positive for both TSH beta and growth hormone or prolactine. From our investigations, the role of Pit-1 in multidirectional differentiation during the development of TSH-secreting adenoma was suggested.

Adenoma↗

PubMed1993

Severe subarachnoid hemorrhage during transsphenoidal surgery for pituitary adenoma.

There are many reports about complications of transphenoidal surgery for pituitary adenomas. We report a patient who suffered severe subarachnoid hemorrhage due to an indirect injury of the intradural internal carotid artery during or immediately after transsphenoidal surgery for pituitary adenoma. An autopsy suggested that a small branch of the intradural internal carotid artery was strongly adherent to the suprasellar portion of the tumor capsule and its avulsion from the internal carotid artery might have been caused as the capsule fell down during the intracapsular removal of the tumor. In a case of pituitary adenoma operated by the transsphenoidal approach the possibility of subarachnoid hemorrhage due to this type of arterial injury, though rare, should be kept in mind.

Adenoma, Chromophobe↗

PubMed1993

[A growing skull fracture: a case report].

A case of growing skull fracture was reported with some considerations on the literature. At the age of 1 year, the patient fell down stairs and struck the right occipital region, but did not receive any treatment at that time. At the age of 19 years, he suffered from several epileptic attacks and was admitted to our ward. Plain craniograms showed a right occipital bone defect measuring 7 x 3 cm in size. CT scan demonstrated a cystic lesion just beneath a membranous substance existing at the bone defect. MRI revealed cystic encephalomalacia underlying the cyst very clearly. At the operation the bone defect was found to be replaced by the granulation tissue which was examined microscopically. Under the granulation tissue, a cyst filled with yellowish fluid and surrounding gliotic brain was found. The dural tear was noticed to be much wider than the bone defect. A dural plasty with LYODURA and a cranioplasty with methacrylic resin were performed. Microscopic examination revealed the granulation tissue to be a fibroglial cicatrix. According to these findings, we concluded that the contused and swollen brain tissue which had herniated through the dural tear had enlarged the skull fracture and formed a fibroglial cicatrix with subcutaneous tissue. It is emphasized that MRI combined with CT scan is an indispensable procedure for diagnosis of growing skull fracture, and microscopic examination contributes to an understanding of its pathogenesis.

Adult↗

PubMed1993

[A case of primary intracranial T cell type malignant lymphoma, radiologically resembling germ cell tumor and presenting hypopituitarism].

A 21-year-old man was hospitalized with complaints of headache, nausea, polyuria, reduced body hair and reduced libido. Plain CT scan and MRI revealed multiple tumors in the pineal and suprasellar regions, and in the dorsal aspect of the medulla oblongata. Endocrinological examination showed hypopituitarism due to hypothalamic dysfunction. Replacement therapy with hydrocortisone was started preoperatively. Suprasellar tumor was explored. Postoperative CT scan and MRI showed marked diminishment of not only suprasellar tumor, but also tumors in the two other regions. These tumors were supposed to be sensitive to corticosteroid hormone. Histopathological diagnosis was T cell type malignant lymphoma. The patient was followed up for 10 months post-operatively with no recurrence on CT scan. Primary intracranial malignant lymphoma is not a rare disease today. However, primary intracranial T cell type lymphoma is extremely rare. Hypopituitarism due to suprasellar malignant lymphoma is also rare, and only 3 such cases have been reported previously. In our case, the tumor was located in the pineal and suprasellar regions, and the dorsal aspect of the medulla oblongata. Such disseminated malignant lymphoma as ours shows radiological resemblance to germ cell tumor. No such diseminated malignant lymphoma has been reported previously. We think that, in its radiological and clinical features, our case is very suggestive of primary intracranial malignant lymphoma.

Adult↗