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ABSTRACT: The presence of progesterone receptors in meningioma tissue is demonstrated by use of highly specific monoclonal antibodies against the rabbit progesterone receptors which cross-react with human progesterone receptors in breast cancer cells, thus giving evidence of the existence of genuine progesterone receptors in human meningiomas.
Surgical Neurology 04/1989; 31(3):172-6. · 1.67 Impact Factor
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ABSTRACT: Intracranial meningiomas from patients treated with medroxyprogesterone acetate as well as from untreated patients were studied in monolayer tissue culture with trials of in vitro hormonal modulation with medroxyprogesterone acetate. The following conclusions were drawn from investigations which comprise 37 cell culture assays: (a) tissue cultures of meningiomas inherit the disadvantages of loss of the progesterone receptor and frequent transformation to cells resembling fibroblasts after three to four passages. For these reasons, drug testing as well as the establishment of cell cultures that exhibit the characteristics of meningioma are impeded; (b) the progesterone receptor-content of the solid tumors does not reflect the response to medroxyprogesterone acetate-therapy in vitro; (c) medroxyprogesterone acetate-pretreated meningiomas showed sufficient in vitro growth in 38%, and untreated meningiomas grew well in 56% of the cases; (d) medroxyprogesterone acetate-induced inhibition or delay of growth was observed in 35%. These findings have resulted in criticism with respect to the value of meningioma tissue cultures for trials of hormonal manipulation and it is thought that another method, which consists of immunostaining of cycling cells, and has been tested in another study, may be superior to cell culture assays with respect to evaluation of the effect of hormonotherapy in meningiomas. Medroxyprogesterone acetate holds an interesting position because it reduces cell growth in some meningiomas in vitro.
Surgical Neurology 03/1989; 31(2):96-100. · 1.67 Impact Factor
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ABSTRACT: The effect of medroxyprogesterone acetate (MPA) on growth fractions of ex vivo meningiomas is demonstrated in using the Ki-67 monoclonal antibody in three cases of meningiomas operated on in two stages and in meningioma specimens from a group of eight patients operated on in one single stage after MPA therapy. Growth fractions in samples from five meningioma patients not treated with MPA were determined for comparison. In the three cases of two-stage operation of the tumors, the percentage of Ki-67-positive cells in meningioma tissue was lower by a factor of 6, 5, and 3, respectively, after MPA therapy. In meningioma specimens from patients receiving no MPA therapy, Ki-67-positive cells were present in 1.02 +/- 0.48%; in samples from MPA-treated tumors the percentage of Ki-67-positive cells was 0.41 +/- 0.40 (different at p less than 0.02 [Wilcoxon's test]). In comparison to our previously published data on untreated meningiomas analyzed for progesterone receptors (PR), MPA significantly reduced the PR activity. There was no obvious correlation between PR activity and potential suppression of the tumor growth fraction. It is concluded that MPA is attractive because it reduces the growth fractions of most meningiomas and might be suitable for adjuvant hormonotherapy.
Surgical Neurology 09/1988; 30(2):97-101. · 1.67 Impact Factor
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ABSTRACT: Fifteen patients with intracranial or spinal meningiomas have been treated with the semisynthetic progestational agent medroxyprogesterone acetate (MPA, Depo-Provera) prior to surgical removal of the tumors in order to investigate the influence of MPA on the progesterone receptor (PR) status of meningioma cytosols. MPA acted as a competitive binder to meningioma-PR: The mean PR values were 15.6 fmol/mg protein (range 0-69) and 338.3 fmol/g tumor (range 0-1190), respectively. In comparison, mean PR values of our untreated meningioma series (n = 58) were 54.9 fmol/mg protein (range 0-586) and 2813 fmol/g tumor (range 0-17,168), respectively. In cases of two-stage resection of meningiomas MPA significantly decreased PR activity in the cytoplasm of meningioma cells. We conclude that MPA binds to meningioma PRs, however, its effect on the growth rate of meningiomas has still to be elucidated.
Surgical Neurology 08/1987; 28(1):3-9. · 1.67 Impact Factor
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ABSTRACT: Estradiol and progestin receptors were studied in 20 patients with neuraxial Schwann cell tumors, and their presence was correlated to the clinicopathologic features and the amount of preoperative corticosteroid therapy. Based on an arbitrary cutoff value of 200 fmol per gram of tumor as indicative of a positive receptor value in breast cancer, 4 and 13 of the neurilemmoma tissue samples could be considered as positive for estrogen and progesterone receptors, respectively. Whereas there was no convincing correlation between the estrogen and progestin receptor activity and the age, sex, or menopausal status of the patients, overweight patients had significantly higher estrogen and progestin binding values. The correlation between the amount of preoperative prednisone therapy and the amount of [3H]estradiol and [3H]promegestone binding revealed no dose relationship. Correlating [3H]estradiol and [3H]promegestone content with the histologic type of the schwannomas (Antoni types A and B, respectively), we were not able to draw conclusions, because of the predominance of Antoni type A over Antoni type B tissues in our material. The necessity of nuclear receptor assays, ligand specificity testing, and in vitro studies is stressed as a prerequisite for answering the questions whether neurilemmomas contain genuine sexual steroid hormone receptors and whether these receptors are regulated via an estrogen-estrogen-receptor system as is the case in classical sexual steroid hormone target tissues.
Surgical Neurology 09/1986; 26(2):142-8. · 1.67 Impact Factor
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ABSTRACT: Six patients with inoperable, nonoperative, or recurrent meningiomas were treated with the antiestrogenic agent tamoxifen (Nolvadex) during an 8-12-month period. Computer tomographic, scintigraphic, and clinical evidence of an unspecific tumor response was only encountered in one patient after 4 months of therapy with tamoxifen. The 2-year results did not indicate a favorable response to antiestrogenic treatment. The significance of sex-steroid receptors and their possible prognostic value in endocrine therapy of meningiomas is discussed.
Surgical Neurology 10/1985; 24(3):245-9. · 1.67 Impact Factor
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ABSTRACT: A consecutive series of 21 adult patients with chronic subdural hematoma was studied in respect to postoperative resolution of subdural collections and clinical improvement after burr hole evacuation without subdural drainage. This series was compared to a previously studied series of patients with chronic subdural hematoma in whom postoperative closed system drainage had been installed. Using the identical protocol for treatment and postoperative follow-up, we obtained identical results with respect to time-related neurological improvement and persistence of subdural collections in the undrained and drained series, except that the steadily progressive clinical improvement during the early postoperative phase (24 hours) in all cases of the drained series was not universal in the undrained cases. Our study suggests that, to avoid the possibility of early postoperative clinical deterioration, burr hole craniostomy and closed system drainage is advisable. We think that subdural drainage is not necessary when the installation of the drainage system seems to be technically difficult, as it may be in cases with considerable perioperative cortical expansion.
Neurosurgery 03/1985; 16(2):185-8. · 2.79 Impact Factor
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ABSTRACT: The end-tidal carbon dioxide partial pressure (PCO2) response curves for the flow velocity in the middle cerebral artery were studied in 31 normal subjects with transcranial Doppler techniques. An exponential curve with an exponent of 0.034 mm Hg-1 was found to be a good fit to the recorded data. By means of this relationship, recordings of flow velocity in cerebral arteries can be normalized to a standard value of PCO2. Physiological aspects of cerebrovascular reactivity to PCO2 and the clinical implications of the PCO2 response curve are discussed. The normal material provides a reference for assessing pathological responses.
Journal of Cerebral Blood Flow & Metabolism 10/1984; 4(3):368-72. · 5.01 Impact Factor
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ABSTRACT: Estradiol and progesterone receptors were studied in 44 patients with meningiomas and correlated to the clinicopathological features and amount of preoperative corticosteroid therapy. Thirty-four (77%) of the meningiomas contained high titers of specific high-affinity cytosol [3H]promegestone (R 5020) binding sites (mean 2,902 fmol/g tumor; range 0-9,598 fmol/g tumor) whereas only miniscule amounts of a nonspecific cytoplasmic [3H]estradiol binding component (mean 48 fmol/g tumor; range 0-201 fmol/g tumor) were detectable. No nuclear binding activity for [3H]estradiol was demonstrable. There was no convincing correlation between high PR activity and the age, sex, or menopausal status of the patients. The correlation study between the amount of preoperative corticosteroid therapy with the amount of [3H]promegestone binding revealed no dose relationship. Correlating [3H]promegestone content with the histologic type, we found 96% of meningothelial, 71% of transitional, and 40% of fibroplastic meningiomas to contain progesterone receptors. The necessity of in vitro studies is stressed to assess the biosynthesis and biological activity of the progesterone receptor in meningiomas, which is apparently not estrogen regulated, as is the case in other estrogen target tissues.
Clinical Neuropharmacology 02/1984; 7(4):368-74. · 2.17 Impact Factor
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ABSTRACT: Primary meningiomas have been grown in monolayer culture and tested for the presence of steroid hormone receptors and sensitivity to various steroids and steroid antagonists. None of the 10 solid tumors or the primary cultures derived from them contained estrogen receptors, either in the cytoplasm or in the nucleus. Progesterone receptors were present in 50-70% of the solid tumors and some of the primary cultures. Four of four and five of five primary cultures contained, respectively, androgen and glucocorticoid receptors. When one of the primary cultures was tested for growth sensitivity to estrogen, tamoxifen, progesterone, hydrocortisone, and dihydrotestosterone, the last two had noticeable stimulatory effects on growth by day 5. Interestingly, only androgen and glucocorticoid receptors were present in the primary tumor cells in culture, suggesting that these receptors mediated the effects of their respective hormones on growth.
Clinical Neuropharmacology 02/1984; 7(4):382-8. · 2.17 Impact Factor
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Surgical Neurology 10/1983; 20(3):263. · 1.67 Impact Factor
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ABSTRACT: Tumor estradiol and progesterone binding sites were studied in 34 patients with meningioma. Twenty of the meningiomas contained very low titers (mean, 45 fmol/g of tumor; range, 0-201 fmol/g of tumor) of a nonspecific cytoplasmic [3H]estradiol binding component, whereas 26 of the tumors contained high titers of specific high-affinity cytosol [3H]promegestone (R5020; progesterone) binding sites (mean, 1476 fmol/g of tumor; range, 0-8328 fmol/g of tumor). No nuclear binding activity for [3H]estradiol could be detected in 12 of the 34 meningiomas studied, irrespective of the progesterone binding activity. There was no correlation between high progesterone binding activity and the age or the sex of the patient, nor between tumor location and cellular mitotic index. However, progesterone binding activity was present more frequently in meningothelial (95%, 18/21 patients) than in transitional (55%, 5/9 patients) or fibroplastic (25%, 1/4 patients) tumor histologic types. These data suggest that the cellular biosynthesis of the progesterone binding component in meningiomas is not estrogen regulated as it is in other classic estrogen target tissues, such as the breast.
Surgical Neurology 08/1983; 20(1):42-7. · 1.67 Impact Factor
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ABSTRACT: In this report the authors describe a noninvasive transcranial method of determining the flow velocities in the basal cerebral arteries. Placement of the probe of a range-gated ultrasound Doppler instrument in the temporal area just above the zygomatic arch allowed the velocities in the middle cerebral artery (MCA) to be determined from the Doppler signals. The flow velocities in the proximal anterior (ACA) and posterior (PCA) cerebral arteries were also recorded at steady state and during test compression of the common carotid arteries. An investigation of 50 healthy subjects by this transcranial Doppler method revealed that the velocity in the MCA, ACA, and PCA was 62 +/- 12, 51 +/0 12, and 44 +/- 11 cm/sec, respectively. This method is of particular value for the detection of vasospasm following subarachnoid hemorrhage and for evaluating the cerebral circulation in occlusive disease of the carotid and vertebral arteries.
Journal of Neurosurgery 01/1983; 57(6):769-74. · 2.96 Impact Factor
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ABSTRACT: We report a rare case of a left frontal ciliated neuroepithelial cyst that fulfilled all criteria (except histological) of an arachnoid cyst. The literature is reviewed, and the possible pathogenetic mechanisms of subarachnoid ependymal cysts are discussed.
Surgical Neurology 01/1982; 16(6):411-4. · 1.67 Impact Factor
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ABSTRACT: A consecutive series of 32 adult patients with chronic subdural hematoma was studied in respect to postoperative cerebral reexpansion (reduction in diameter of the subdural space) after burr-hole craniostomy and closed-system drainage. Patients with high subdural pressure showed the most rapid brain expansion and clinical improvement during the first 2 days. Nevertheless, a computerized tomography (CT) scan performed on the 10th day after surgery demonstrated persisting subdural fluid in 78% of cases. After 40 days, the CT scan was normal in 27 of the 32 patients. There was no mortality and no significant morbidity. Our study suggests that well developed subdural neomembranes are the crucial factors for cerebral reexpansion, a phenomenon that takes at least 10 to 20 days. However, blood vessel dysfunction and impairment of cerebral blood flow may participate in delay of brain reexpansion. It may be argued that additional surgical procedures, such as repeated tapping of the subdural fluid, craniotomy, and membranectomy or even craniectomy, should not be evaluated earlier than 20 days after the initial surgical procedure unless the patient has deteriorated markedly.
Journal of Neurosurgery 10/1981; 55(3):390-6. · 2.96 Impact Factor
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ABSTRACT: The authors present two cases of vertebral chordomas with widespread metastases. The literature is reviewed and the metastatic potential of chordomas is analysed.
Surgical Neurology 01/1980; 12(6):473-8. · 1.67 Impact Factor
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ABSTRACT: The authors present a rare case of a meningioma in the anterior part of the third ventricle in a 10-year-old boy which was successfully removed through a right-sided transventricular approach. The literature is reviewed.
Surgical Neurology 08/1979; 12(1):29-32. · 1.67 Impact Factor
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ABSTRACT: The authors describe a case of hemispheric brain cyst of possible neuroectodermal origin, presenting as a frontotemporoparietal mass lesion. The etiologic aspects of intracranial neuroepithelial cysts are discussed.
Surgical Neurology 04/1979; 11(3):195-8. · 1.67 Impact Factor
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ABSTRACT: The authors present a case of meningioma located in the anterior part of the third ventricle. The mass was successfully removed through a right-sided transventricular approach after stereotaxic biopsy. A review of the relevant literature is included.
Journal of Neurosurgery 03/1979; 50(2):233-5. · 2.96 Impact Factor
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ABSTRACT: Two cases of primary intraventricular oligodendrogliomas which were successfully removed by a transventricular approach using microtechniques are presented. Oligodendrogliomas in this location are very rare. The literature is reviewed.
Surgical Neurology 02/1979; 11(1):25-8. · 1.67 Impact Factor
