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O Kubo

Publications and source records attributed to O Kubo.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Lymphoplasmacyte-rich meningioma: a report of three cases and a review of the literature].

We report three patients (a 36-year-old man, a 41-year-old woman, and a 22-year-old man) with lymphoplasmacyte-rich meningioma who manifested characteristics on radiological and blood examinations. Two were hospitalized with gradual deterioration of hemiparesis and one with general convulsive seizure. Radiological examination revealed typical meningiomas of convexity in two and that of falx in one. Two of the patients showed large perifocal edema. Anemia was found in one patient and an elevated level in the zinc sulfate turbidity test was noted in all cases. Abnormal findings in laboratory examination improved quickly, whereas perifocal edema remained for six months after tumor removal. The tumors were histologically confirmed to be meningioma with massive infiltrates of plasma cells and lymphocytes. Seventeen cases of lymphoplasmacyte-rich meningioma that have been reported to date including our three cases were reviewed.

Adult↗
PubMed1999

Detection of mammosomatotrophs in paraffin-embedded specimens of various pituitary adenomas.

BACKGROUND: There are various classification systems for pituitary adenomas based on whether mammosomatotroph cells, which simultaneously express both prolactin (PRL) and growth hormone (GH), can be found. Until the present, the identification of such cells required special techniques and could not be performed in paraffin-embedded specimens. This hindered large-scale studies for detection of mammosomatotrophs in various pituitary adenomas and, as a result, such classification has remained controversial. To establish a methodology for the detection of mammosomatotrophs in paraffin-embedded specimens and to propose a more logical classification for pituitary adenomas, the authors conducted this retrospective study. METHODS: We performed double immunofluorescence staining of PRL and GH in paraffin-embedded specimens of various pituitary adenomas with subsequent observation with a confocal laser-scanning microscope. RESULTS: Mammosomatotrophs were found in four of the 10 GH-secreting adenomas and one of the 10 clinically nonfunctioning adenomas. However, mammosomatotrophs were not identified in all 10 cases of prolactinoma. CONCLUSIONS: This is the first report in the literature that successfully demonstrates the presence of mammosomatotrophs in routine paraffin-embedded pituitary adenomas. The new methodology is important for future study of the function and role of these cells. A large-scale study for mammosomatotrophs in various pituitary adenomas with this method and a more logical classification of pituitary adenomas are proposed.

Adenoma↗
PubMed1999

[Immunohistochemical evaluation of intracranial recurrent meningiomas: correlation of topoisomerase II alpha expression and cell proliferative potential].

Most of meningiomas belong to benign tumor. But inspite of Simpson grade I surgical resection, it had been reported that a part of these cases recurred after initial operation. In discussing tumor recurrence in meningioma, it is important to evaluate not only the extent of surgical resection and malignancy but also cell proliferative potential, which had been studied immunohistochemically by using BudR, PCNA and MIB-1. Recently, it is known that topoisomerase (Topo) II alpha expression becomes remarkable in tumorigenesis. The correlation with cell proliferative potential has been reported. In this paper we evaluated the relationship of cell proliferative potential and tumor recurrence immunohistochemically by using Topo II alpha and MIB-1 monoclonal antibody in the 21 recurrent cases of meningiomas and hemangiopericytomas. As a result, mean Topo II alpha staining index (SI) and MIB-1 SI initial surgical resection were 2.29% and 3.41%, respectively, at recurrence these SIs had risen at 4.3% and 6.25%, respectively. As to the interval from initial surgical resection to recurrence, in the cases which recurred under 3 years Topo II alpha SI and MIB-1 SI were 3.13% and 5.00%, on the other hand, in the cases which recurred later than 3 years were 1.16% and 1.30%, respectively. Topo II alpha SI and MIB-1 SI 1 of former cases were higher than latter cases. Furthermore good correlation between the Topo II alpha SI and MIB-1 SI was found. It is concluded that Topo II alpha expression was as well available for the marker of cell proliferative potential and for one of the predicting factors for tumor recurrence in meningioma and hemangiopericytoma as MIB-1 SI.

Adult↗
PubMed1998

Involvement of 5-hydroxytryptamine7 receptors in inhibition of porcine myometrial contractility by 5-hydroxytryptamine.

1 5-Hydroxytryptamine (5-HT; 1 nM - 100 microM) concentration-dependently inhibited the amplitude and frequency of spontaneous contractions in longitudinal and circular muscles of the porcine myometrium. The circular muscle (EC50; 68-84 nM) was more sensitive than the longitudinal muscle (EC50; 1.3-1.44 microM) to 5-HT. To characterize the 5-HT receptor subtype responsible for inhibition of myometrial contractility, the effects of 5-HT receptor agonists on spontaneous contractions and of 5-HT receptor antagonists on inhibition by 5-HT were examined in circular muscle preparations. 2 Pretreatment with tetrodotoxin (1 microM), propranolol (1 microM), atropine (1 microM), guanethidine (10 microM) or L-NAME (100 microM) failed to change the inhibition by 5-HT, indicating that the inhibition was due to a direct action of 5-HT on the smooth muscle cells. 3 5-CT, 5-MeOT and 8-OH-DPAT mimicked the inhibitory response of 5-HT, and the rank order of the potency was 5-CT>5-HT>5-MeOT>8-OH-DPAT. On the other hand, oxymethazoline, alpha-methyl-5-HT, 2-methyl-5-HT, cisapride, BIMU-1, BIMU-8, ergotamine and dihydroergotamine had almost no effect on spontaneous contractions, even at 10-100 microM. 4 Inhibition by 5-HT was not decreased by either pindolol (1 microM), ketanserin (1 microM), tropisetron (10 microM), MDL72222 (1 microM) or GR113808 (10 microM), but was antagonized by the following compounds in a competitive manner (with pA2 values in parentheses): methiothepin (8.05), methysergide (7.92), metergoline (7.4), mianserin (7.08), clozapine (7.06) and spiperone (6.86). 5 Ro 20-1724 (20 microM) and rolipram (10 microM) significantly enhanced the inhibitory response of 5-HT, but neither zaprinast (10 microM) nor dipyridamole (10 microM) altered the response of 5-HT. 6 5-HT (1 nM - 1 microM) caused a concentration-dependent accumulation of intracellular cyclic AMP in the circular muscle. 7 From the present results, the 5-HT receptor, which is functionally correlated with the 5-HT7 receptor, mediates the inhibitory effect of 5-HT on porcine myometrial contractility. This inhibitory response is probably due to an increase in intracellular cyclic AMP through the activation of adenylate cyclase that is positively coupled to 5-HT7 receptors.

Adenylyl Cyclases↗
PubMed1998

[Clinical evaluation of intraoperative radiotherapy using photon radiosurgery system for brain tumors].

The photon radiosurgery system is a miniature X-ray generator that can be placed stereotactically and intraoperatively into intracranial tumors to deliver a single fraction of high-dose interstitial irradiation. This battery-powered device produces low energy X-ray photons in a spherical and symmetrical pattern at the probe tip. Dose rates of up to 200 cGy/Mim are possible, allowing for the administration of 15 Gy to a lesion 3 cm in diameter in less than 1 hr. Background exposure is minimal, and no special shielding of the patient or health care personnel is required. Thirty-nine patients with brain tumor were treated in this method. There were no adverse effects. During the follow-up period of 1-30 months, 3 cases with 5 metastatic brain tumors died about 8 months after this treatment. Five recurrent cases of 21 malignant gliomas died about 4 months after treatment. Interstitial radiotherapy using photon the radiosurgery system promises to be a useful treatment for brain tumors.

Aged↗
PubMed1997

Spontaneous regression of primary intracranial germinoma. A case report.

BACKGROUND: Testicular seminomas are well known to regress spontaneously at a higher incidence than other tumors. To date, there have been no reports of spontaneous regression of an intracranial germinoma, although these tumors are histologically identical to testicular seminomas. METHODS: The authors present a patient with a primary intracranial germinoma that regressed spontaneously. RESULTS: A 21-year-old man was admitted to the study facility with acute onset of headache and vomiting. He had a 3-year history of polydipsia and polyuria. Computed tomography (CT) demonstrated a large tumor in the third ventricle, accompanied by hydrocephalus. He underwent ventriculoperitoneal shunt placement on the second day of hospitalization. A CT scan obtained on the fifth postoperative day demonstrated a remarkable decrease in tumor size. Because serial magnetic resonance imaging (MRI) demonstrated a gradual decrease in tumor size, tumor resection was not performed at that time. The patient was discharged and followed with MRI. The tumor continued to regress for more than 2 months. The patient was readmitted due to tumor regrowth, confirmed by MRI 4 months after the initial admission, despite the absence of symptom exacerbation. Two weeks later, the suprasellar portion of the tumor was resected through a right frontotemporal craniotomy. The histopathologic diagnosis was a germinoma. No concurrent tumors were found on whole body examination. The residual tumor gradually regressed after conventional radiation therapy and there has been neither tumor recurrence nor metastasis to date. CONCLUSIONS: Although the precise cause of the transient partial regression is unknown, this case indicates that, like their testicular counterparts, intracranial germinomas may on occasion spontaneously regress.

Adult↗
PubMed1997

Expression and role of cadherins in astrocytic tumors.

Cadherins are Ca(2+)-dependent cell adhesion molecules that play an important role in tissue formation and morphogenesis in multicellular organisms. In recent years, there have been reports of cadherin involvement in tumor invasion and metastasis. Twenty-two surgical specimens and some cultured cells were studied by immunohistochemical staining. No significant difference was observed in the patients with anaplastic astrocytoma, whereas decreased expression of N-cadherin was detected at the time of recurrence in those with glioblastoma. In these groups, cerebrospinal fluid dissemination was found, and contralateral cerebral metastases and extracranial metastases were observed. We conclude that decreased N-cadherin expression at the immunohistochemically demonstrated time of recurrence correlates with tumor invasion and dissemination of cerebrospinal fluid.

Adult↗
PubMed1997

Tumor cell counting using an image analysis program for MIB-1 immunohistochemistry.

A cell counting method for MIB-1 immunohistochemistry, using an image analysis program, NIH Image, on a personal computer, has advantages over manual cell counting by microscopy. MIB-1 slides were photographed at a magnification of x 50 on 24 x 36 mm color films and the photographs were then enlarged to adequate size for observation. The MIB-1-positive cells, on the enlargements, were marked with a white pen, and negative cells with a black pen. Subsequently, the image of an enlargement was converted into data that can be processed by the program using a flatbed image scanner. Threshold levels were adjusted according to the respective white and black markings, and the program automatically counted the number of MIB-1-positive and negative tumor cells. Our method has the following significant advantages: Once cells had been marked and the image converted into the NIH Image data, the cell count process was completed within a few minutes; in contrast to manual microscopic cell counting, count overlapping or cells missed by the observer are eliminated; overlapping nuclei could be separated by the marking procedure; our method required no elaborate and costly image analysis system. The present method may be recommended to researchers undertaking cell kinetic studies utilizing immunohistochemical methods.

Brain Neoplasms↗
PubMed1997

[Management of increased intracranial pressure in metastatic brain tumor].

Metastatic brain tumors generally accompany huge peripheral edema, and half of the cases have multiple lesions. Thus, one must manage the increased intracranial pressure (IICP). Ideally, local control of the tumor progression by surgical removal with radiation or radiosurgery is the best method to reduce IICP. We usually use a glyceol or steroids as medical treatment. Steroids are effective for peripheral edema, and we have used them for inoperable patients over the long term. One should estimate the condition of the primary lesion, systemic metastasis, and intracranial lesion in order to determine the therapy to assure patients the best quality of life.

Brain Neoplasms↗
PubMed1997

[A case of giant cell-rich gliosarcoma].

We report a case of gliosarcoma with numerous giant cells resembling ganglion cells and having clear nucleoli. A 75-year woman was admitted to our hospital suffering from progressive left hemiparesis and ambulatory disturbance of one week's duration. CT and MRI studies showed ring enhancement on a clear margin mass in the right parieto-occipital lobe. The mass was totally removed macroscopically. Her left hemiparesis had improved and self walk came to be possible. But the tumor was regrowthed during next two months and she died for three months and a week. The gross and microscopic appearances of the tumors showed the double structure. The surface of the tumor was well enhanced and consisted of soft, gray, and easily bleeding tissue. The central core, however, was poorly enhanced and consisted of hard, yellow, non-bleeding tissue. Macroscopically, the central area included numerous giant ganglion-like cells which were negative for GFAP but positive for EMA in the cytoplasm. These giant cells had abundant collagen fibers and were surrounded by such fibers. Microscopic findings of the surrounding area included numerous spindle shaped cells which were positive for GFAP and vimentin. The origins of giant cells or tumor tissues have long been discussed, but no consensus has yet been obtained. Therefore, we speculated as to the origin in our patient based on immunohistochemical study and the findings of electronmicroscopy. We concluded, in sharp contrast to the old theory of one origin, epithelial tissue of a hamartomatous nature existed initially, followed by the growth of malignant tissue of a reactive astrocytic tumor with a sarcomatous component.

Aged↗
PubMed1996

MIB-1 staining index and peritumoral brain edema of meningiomas.

BACKGROUND: Growth rates and tumor aggressiveness of meningiomas are thought to be closely related to brain edema development. However, histopathologic data alone are not consistently accurate predictors of the behavior and clinical course of a meningioma. METHODS: The authors examined 57 histologically proven intracranial meningiomas to identify factors, including growth fractions determined by MIB-1 immunostaining, that may influence the development of meningioma-associated peritumoral brain edema. There were 54 benign, 2 atypical, and 1 anaplastic meningiomas. The MIB-1 staining index (SI) percentage was defined as the number of MIB-1 positive cells divided by the total number of tumor cells in a 1.037-square millimeter area on the slide. The extent of peritumoral brain edema was determined using preoperative magnetic resonance imaging. The extent of edema was classified as Grade 0,1, or 2 (GR0, GR1, or GR2), in order of increasing severity. RESULTS: The MIB-1 SIs of the 57 cases ranged from 0.06-6.8% (median, 0.80%). There were 26 GR0, 20 GR1, and 11 GR2 edema cases. The MIB-1 SI rose in order of increasing edema severity. There was a statistically significant correlation between the MIB-1 SI and the extent of brain edema (P<0.0001), and also between the tumor size and the extent of brain edema (P=0.001). Meningothelial and atypical/anaplastic meningiomas were associated with peritumoral brain edema more often than any other subtype (P<0.005). CONCLUSIONS: Growth fractions, as determined by MIB-1 immunostaining, rise with increasing severity of peritumoral brain edema, indicating a close relationship between tumor aggressiveness and edema development.

Adult↗
PubMed1996

Inhibin alpha and beta A subunit messenger ribonucleic acids expression in human pituitary adenomas: studies by quantitative reverse transcription-polymerase chain reaction.

Inhibin alpha and beta A subunit messenger ribonucleic acid (mRNA) levels were measured quantitatively by reverse transcription-polymerase chain reaction (RT-PCR) in human pituitary adenomas. The inhibin alpha subunit mRNA levels were undetectably low in cultured adenoma tissues, but beta A mRNA were 0.383 +/- 0.074 in 3 GH adenomas, 0.672 +/- 0.140 in 3 prolactinomas and 0.957 +/- 0.414 molecules/cell in 3 non-functioning adenomas. The addition of 10(-8) M activin A decreased the beta A mRNA levels within 4 h in 1 of 3 GH adenomas, 2 of 3 prolactinomas and 2 of 3 non-functioning adenomas, though the decreases were not statistically significant. The results showed an abundance of beta A subunit mRNA compared with alpha subunit mRNA in all human pituitary adenomas and a local role for activin in its own production through inhibin beta A mRNA subunit expression.

Adenoma↗
PubMed1996

Inhibin alpha, beta A and beta B subunit messenger ribonucleic acid levels in cultured rat pituitary: studies by a quantitative RT-PCR.

Recent studies have demonstrated that inhibins and activins both play not only endocrine roles but also local regulatory roles in gonadotoropin secretion. There has been controversy as to the subtype of rat pituitary inhibin/activin. We studied the levels of inhibin alpha, beta A and beta B subunit mRNAs by a quantitative reverse transcription-polymerase chain reaction (RT-PCR) and the changes in their levels by adding inhibin alpha, beta A and beta B mRNA antisense oligonucleotides and inhibin A, activin A or GnRH to cultured rat anterior pituitary cells. This study demonstrated the level of 3 mRNAs to be 1.6 x 10(-2), 0.75 and 3.4 x 10(-2) molecules/cell with a molar ratio of 1:50:2. A stimulatory role for activin B in FSH secretion was suggested as beta B mRNA antisense oligonucleotide decreased FSH secretion. The beta B mRNA level tended to be decreased by the addition of activin A, but the decrease was not statistically significant. GnRH did not affect alpha and beta B mRNA levels when administered singly. The level of beta A mRNA was not changed by any of the above treatments. In conclusion, the presence of inhibin alpha, beta A and beta B subunit mRNAs in the rat anterior pituitary with the greatest abundance of beta A was demonstrated by using RT-PCR. Activin B or activin AB may play important roles in FSH secretion in an autocrine or a paracrine fashion, and activin A may play an indirect role in FSH secretion.

Activins↗
PubMed1996

Demonstration of activin in normal pituitary and in various human pituitary adenomas by immunohistochemistry.

Inhibins and activins have been known to modify the secretion of various pituitary hormones. To study whether inhibins and activins are present in human pituitary tissues, immunohistochemical studies with antisera to activin A and inhibin alpha subunit were performed on 9 human pituitary adenoma tissue specimens and one sample of normal pituitary tissue adjacent to one adenoma. Activin immunoreactivities were demonstrated in the cytoplasms of one GH and one PRL and two non-functioning adenomas and one normal pituitary tissue, but they were negative in one PRL, one ACTH, one FSH and two non-functioning adenomas. Thus, the presence and absence of activin in the same type of adenoma in regard to hormone production, suggested that the difference in immunostaining simply reflected the difference in the activin concentration. In contrast to this, inhibin alpha subunit immunoreactivity was not found in any of the tissues studied. These data suggested a local synthesis of activin in the normal pituitary as well as various kinds of pituitary adenoma tissues and its local role in the human pituitary gland.

Activins↗
PubMed1996

[The relationship between cell proliferation activity and secretory activity in pituitary adenoma--a review of 63 cases].

Determination of the cell proliferation activity of neoplasm is useful in making a prognosis. Immunohistochemical detection using MIB-1 monoclonal antibody has recently allowed us to assess tumor cell proliferation easily, because it can be performed on paraffin-embedded specimens and the results have been demonstrated to be positively correlated with the results of PCNA staining. In this study, surgical specimens of 63 pituitary adenomas were examined by immunohistochemical staining with MIB-1 monoclonal antibody. Twenty-nine cases were non-functioning pituitary adenomas, 20 were prolactin (PRL)-producing pituitary adenomas, and 14 were growth hormone (GH)-producing pituitary adenomas. The MIB-1 positive rates of the pituitary adenomas ranged from 0% to 6.46%. In the non-functioning pituitary adenomas, the MIB-1 positive rates ranged from 0% to 4.55% (mean : 0.76%), in the PRL-producing pituitary adenomas the MIB-1 positive rates ranged 0% to 6.46% (mean : 0.91%), and in the GH-producing pituitary adenomas the MIB-1 positive rates ranged 0% to 1.28% (mean: 0.58%). There were no significant differences between these values according to the results of the Wilcoxon signed-rank test. Although the size of the non-functioning pituitary adenomas was not correlated with their MIB-1 positive rate, tumor size was closely correlated with the interval between the onset of the initial symptoms and the date of surgery. In the PRL-producing pituitary adenomas, the MIB-1 positive rate was not correlated with serum PRL levels as an index of secretory activity, but was correlated with the PRL staining positive rate. Preoperative bromocriptine therapy proved effective in reducing tumor size and serum PRL levels, but had no effect on the MIB-1 positive rate. In the GH-producing pituitary adenomas, the MIB-1 positive rate was not correlated with serum GH levels as an index of secretory activity, but was closely correlated with the GH staining positive rate. All three groups included both invasive and noninvasive tumor types, but there were no close statistical correlations between the three tumor types.

Adenoma↗
PubMed1996

[A clinico-pathological study of cystic spinal Schwannomas].

It is not rare for a spinal Schwannoma to have cystic formations, but there are various opinions about the mechanism. Since the installation of MRI in our institution in 1989, we have experienced 4 cases of cystic spinal Schwannoma. The diagnosis of such lesions was based on identifying cystic formations histopathologically. Among these cases, tiny hemorrhages were noted microscopically in three of them along with hemosiderin depositions and phagocytes containing hemosiderin. Besides, there are also a lot of sinusoidal vessels with thin endothelium. Perhaps in these three cases, it is the tiny hemorrhages that resulted in degenerative changes which in turn caused the formation of microcysts. But in addition to the above findings, a lot of hyalinized vessels were also demonstrated in the angiomatous components of two cases. Therefore, it is also possible that the microcyst formation is secondary to the degenerative changes caused by ischemia within the tumors. On the other hand, in the only case without hemorrhage, neither phagocytes containing hemosiderin nor abnormal sinusoidal vessels could be found. In stead, a lot of clear foamy cells with positive lipid staining were seen. There may be some factors underlying the xanthomatous change of these tumors that cause their vacuolar formation from degenerated of the foamy cells. It is possible that all three factors mentioned above may act alone or in combination to contribute to the formation of cysts. At its late stage, a spinal Schwannoma may have various findings which can not be classified into either Antoni A or Antoni B type. In conclusion, a spinal Schwannoma can occasionally have cystic formations. Its mechanisms can be a hemorrhagic or an ischemic process occurring within the tumor.

Adult↗
PubMed1996

A clinico-immunohistochemical study of giant cell glioblastoma.

We have reported 7 cases of giant cell glioblastoma. All cases died within 14 months despite aggressive treatment. By immunohistochemical staining, lymphocyte infiltration was found in 6 cases. GFAP and vimentin stained positive in all cases. The MIB-1 positive rate was 13.8-90% (average, 34.9%); small and mononucleated giant cells stained more than multinucleated and monstrous cells. It was concluded that this tumor can be highly malignant and its degree of malignancy is determined by the biological behavior of the mononucleated giant cells and small cells.

Adult↗