Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In 13 Fischer 344 rats transplanted intracerebrally with 9 L gliosarcoma, 13 normal Fischer 344 rats and 4 clinical cases of malignant glioma, a new water-soluble nitrosourea (MCNU) was given and the concentration was measured in blood, tumor tissues, normal brains around the tumors and normal hemispheres by intravenous or intraarterial infusion of MCNU. At 5 min. after administration of MCNU 20 mg/kg (4-5 mg/body) in 9 L gliosarcoma bearing Fischer rats, mean MCNU concentration in the blood was not different between 20 micrograms/ml intravenous and 23 micrograms/ml intraarterial administrations whereas that in the tumor tissues by intracarotid infusion of MCNU was 40 +/- 14.4 micrograms/g which was about two times as much as 22.9 +/- 8.13 micrograms/g by intravenous infusion of MCNU. Mean MCNU concentration of normal brains around tumor tissues was 2.49 micrograms/g in intravenous and 8.95 micrograms/g in intracarotid infusion. MCNU concentration of tumor tissues in 4 cases of malignant gliomas was higher by intracarotid administration than by intravenous administration compared to that in the blood. Maximum tumor/blood ratio of MCNU was 1.94 in intracarotid administration for the malignant glioma. It is suggested that intraarterial administration was more useful than intravenous infusion as an administration route for malignant brain tumors.
 ...
PMID:[MCNU delivery into malignant brain tumor and normal brain tissue by intravenous or intraarterial infusion]. 215 61

Hexose monophosphate shunt (HMPS) activity can be measured with 1H nuclear magnetic resonance spectroscopy or gas chromatography--mass spectrometry by monitoring the differential production of [3-13C]lactate and [3-12C]lactate from the degradation of [1-13C]-glucose. Errors in measurement of HMPS activity can arise from unlabeled lactate precursors, by recycling of HMPS products, and by incomplete fractional enrichment of labeled glucose. A method utilizing cultured cells incubated with [1-13C]glucose in parallel with incubations using [6-13C]glucose to correct for all these problems is presented. In cultured rat C6 glioma and 9L gliosarcoma cells, failure to apply this correction results in an approximately twofold overestimation of HMPS activity.
 ...
PMID:Hexose monophosphate shunt measurement in cultured cells with [1-13C]glucose: correction for endogenous carbon sources using [6-13C] glucose. 233 80

Photodynamic therapy is under intense investigation as an adjuvant treatment for malignant glial tumors of the central nervous system. Photofrin-II (HpD-II) is currently the most actively investigated photosensitizing agent. A crucial issue regarding the safe and efficacious usage of HpD-II-based photodynamic therapy is the individual in vivo kinetics of tumor uptake and retention, compared with normal brain clearance. The optimal time for photoactivation of sensitized tumor must be known to ensure a high target-to-nontarget ratio, resulting in the maximal tumor destruction while preserving normal brain. Our laboratory developed a radionuclide scan based on 111indium (111In)-labeled HpD-II to evaluate HpD-II localization and clearance noninvasively within a canine model of intracerebral gliosarcoma. Synthesis of the 111In-HpD-II complex in greater than 90% yield is achieved by a simple, rapid labeling method. Radiochemical purity and stability were verified by high-performance liquid chromatography. Using the canine model of intracerebral gliosarcoma, we followed the uptake of 111In-HpD-II in tumors with serial scintillation scanning. Localization of the tumor by 111In-HpD-II has been verified by contrast-enhanced computed tomographic scan followed by gross and histological examination of the enhancing brain region. Total body biodistribution of 111In-HpD-II at various times after injection has been evaluated. The ratio of uptake in tumor compared with surrounding brain peaked at 72 hours after injection. The knowledge of regional distribution and concentration of a photosensitizing agent within a tumor mass and surrounding brain allows for the most efficacious timing and localization of a photoactivating source.
 ...
PMID:Indium-111-Photofrin-II scintillation scan. 252 21

We studied the feasibility of intrathecal ACNU perfusion therapy against subarachnoid dissemination of malignant glioma. Intrathecal perfusion was performed in adult dogs by constant drip administration of 1 to 2 mg ACNU dissolved in 10 to 20 ml of lactate Ringer solution into the lateral ventricle and cerebrospinal fluid drainage through the lumbar puncture. The perfusion time was changed from 15 to 71 min. A bolus injection of 2 mg ACNU was also tested in one dog. No neurological symptom was noted during and after perfusion, and histological examination reveal only a minimum denudation of ependyma in a small area. Concentration of ACNU in CSF and serum were measured by HPLC (high-performance liquid chromatography). ACNU was detected in lumbar CSF only by perfusion, not by bolus injection, and the maximum concentrations were 6.26 to 25.76 micrograms/ml. The elimination phase of ACNU in lumbar CSF followed linear kinetics and the half-time was 18 min on average. AUCs (area under the drug concentration-time curve) were 346 to 896 micrograms.min/ml and they were the equivalent of in vitro cell kills in excess of 3 logs for rat 9L gliosarcoma and human glioma 126 cells. Serum concentration was 0.10 micrograms/ml in maximum. These findings suggest the feasibility of intrathecal ACNU perfusion therapy against subarachnoid dissemination of malignant glioma and warrant further studies.
 ...
PMID:[Intrathecal perfusion of ACNU neurotoxicity and intrathecal pharmacokinetics in dogs]. 258 15

Formalin-fixed and paraffin-embedded specimens of 24 human gliomas were examined histochemically with five lectins; concanavalin A (Con A), wheat germ agglutinin (WGA), Ricinus communis agglutinin 1 (RCA-1), peanut agglutinin (PNA), and Ulex europaeus agglutinin 1 (UEA-1). Although the staining intensity with lectins was variable, tumor cells in five astrocytomas, three oligodendrogliomas, six ependymomas, and one gliosarcoma, were generally positive for Con A, WGA, and RCA-1, and negative for PNA and UEA-1, whereas those in nine glioblastomas were usually positive for Con A and WGA and negative for RCA-1 and PNA as well as UEA-1. The malignancy in neoplastic astrocytes was correlated with the decrease in binding with lectins, especially RCA-1. Blood vessels, particularly the endothelial layers, in all gliomas were stained intensely with all lectins used. Macrophages showed two staining features with lectins; stippled and granular. The former macrophages were positive for Con A, WGA, RCA-1, and PNA, and negative for UEA-1, whereas the latter macrophages were positive for all lectins used. Thus, the staining characteristics with lectins of macrophages were different from those of any glioma cells and very useful for identification of macrophages in gliomas.
 ...
PMID:Lectin histochemistry of human gliomas. 259 66

Astroblastomas are rare, usually circumscribed, supratentorial tumors of young subjects and are characterized by a perivascular arrangement of the tumor cells. Their clinical behavior is unpredictable and their prognosis has been regarded as intermediate between that of astrocytomas and glioblastomas. A personal series of 23 astroblastomas was reviewed, adequate postoperative follow-up being available in 13 patients. Two distinct histological types were encountered: low-grade and high-grade. The low-grade type comprised tumors with better differentiated and more benign-appearing microscopical features. Five of the 8 patients with tumors of this type who were available for follow-up have survived from 3 to 20 years after treatment; in 1 patient the tumor converted into a fatal glioblastoma after 4 1/2 years. The high-grade type consisted of tumors with more anaplastic features. Three of the 4 patients with tumors of this type available for follow-up died after 1 1/2 to 2 1/2 years, the astroblastomas in 2 of them having converted into a glioblastoma and a gliosarcoma, respectively. One patient, however, has had an unexpected length of postoperative survival of 11 1/2 years. The best clinical results were obtained after total or subtotal resection of the tumor, followed by radiotherapy. The role of chemotherapy is still uncertain. This form of glioma illustrates the discrepancies that may sometimes be apparent between histopathological features and length of postoperative survival. The prognosis is also further complicated by the potential of the astroblastoma to convert into a more malignant type of glioma.
 ...
PMID:Astroblastomas: a pathological study of 23 tumors, with a postoperative follow-up in 13 patients. 275 81

In an attempt to improve glioma management, an animal model was developed to evaluate the therapeutic efficacy of intra-arterial 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). Furthermore, the model was used to study the antitumor activity of D,L-alpha-difluoromethylornithine (DFMO), a polyamine-biosynthesis inhibitor, used both as a single agent and in combination with intra-arterial BCNU. An N-methylnitrosourea-induced gliosarcoma (T9) was transplanted stereotaxically into the right caudate nucleus of male Fischer 344 rats. Animals receiving a single low-dose (5 mg/kg) intracarotid injection of BCNU 9 days following tumor implantation had a 57% increase in life span compared with untreated control rats (p less than 0.001). Intracarotid drug delivery was more effective than systemic (intraperitoneal) administration of the same dose of BCNU. When given as a single agent, DFMO demonstrated dose-dependent effectiveness. As part of a combined regimen, DFMO enhanced the antitumor therapeutic activity of both systemic (intraperitoneal) and intra-arterial BCNU. Survival times of animals receiving combined DFMO and intra-arterial BCNU were almost double those of untreated controls, and were significantly better than survival times of animals receiving combined DFMO and intraperitoneal BCNU. These findings suggest methods to optimize current clinical chemotherapy for glioma.
 ...
PMID:Effect of difluoromethylornithine on the antiglioma therapeutic efficacy of intra-arterial BCNU. 309 5

The in vivo uptake and metabolism of radiolabeled putrescine was examined in two glioma models: (a) the T9 gliosarcoma in the CD Fischer rat and (b) the U-87 MG human glioblastoma in the athymic (nude) mouse. Autoradiography after parenteral administration of [14C]putrescine revealed rapid and selective uptake by both tumors compared with normal brain. Polyamine analysis of the rat gliosarcoma demonstrated minimal conversion of labeled putrescine to its metabolites, spermidine and spermine, at 5 and 30 minutes after intravenous injection. The human glioblastoma also exhibited minimal polyamine conversion at 5 minutes, although there was a trend toward significant metabolism at longer time periods (30 and 45 minutes). In addition, the human glioblastoma produced nonpolyamine metabolites that suggest an alternative pathway of putrescine metabolism via gamma-aminobutyric acid. These in vivo findings are discussed in relation to the usefulness of putrescine as a marker for positron emission tomography of human gliomas.
 ...
PMID:In vivo metabolism of radiolabeled putrescine in gliomas: implications for positron emission tomography of brain tumors. 326 87

A cell line (NCE-G28) was established from the biopsy material of a human gliosarcoma of low histological differentiation. The initial cultures showed a mixed population of cells which in later stages became more uniform due to loss of slower growing constituents. The cells have been growing steadily for 20 months. A suspension of NCE-G28 cells injected s.c. as well as i.p. into nude mice produced solid tumors in all cases. Histologically these tumors closely resembled the original tumor. The original tumor, the nude mouse tumor, and NCE-G28 cells were immunochemically positive for glial fibrillary acidic protein as well as for neural plasma membrane antigen A2B5 expression. Two cell strains, 9B2C and 9B2E, were obtained by cloning of the initial cultures and another strain, NCE-G28T, was derived after explantation of a mouse heterotransplant. The two subclones were negative for glial fibrillary acidic protein expression but stained for cell surface fibronectin. NCE-G28T cells initially were positive for glial fibrillary acidic protein but lost this property within 8 months of cultivation. Karyotype analysis of NCE-G28 and the three strains revealed hyperdiploidy and six structurally altered marker chromosomes five of which were shared by nearly all cells. Receptors for epidermal growth factor were detected in all cell lines with the highest levels (about 300,000 receptors/cell) in the parental cell line. The epidermal growth factor receptors had an affinity of 2.5 nM (Kd) and by affinity cross-linking analysis a molecular weight of 170,000 was found. Initially, NCE-G28 cells responded to epidermal growth factor as well as fibroblast growth factor with increased rates of proliferation, while platelet derived growth factor had no effect. In higher passages the growth factor sensitivity was reduced. Using antibodies directed against synthetic protooncogene peptides the production of c-sis immunoreactive material was detected. NCE-G28 cells produce an autocrine factor which stimulated proliferation. This factor is present in conditioned medium and is active on cultured meningiomas and other glioma cell lines. NCE-G28 cells can be maintained in serum-free defined medium on plastic coated with fibronectin or an extracellular matrix from bovine corneal endothelial cells. The NCE-G28 cell line with its strains provide an in vitro model system in which the complexity of gliosarcoma cell populations and the interaction of the cloned cellular constituents can be studied.
 ...
PMID:Biological and karyotypic characterization of a new cell line derived from human gliosarcoma. 327

The occurrence of a glioblastoma with sarcoma, a gliosarcoma, in the left frontal-temporal area of a 49-year-old woman with a history of Thorotrast exposure, is described. Thorotrast-laden histiocytes and free Thorotrast material were found in both components of the tumor. An overlying, adherent dural cranial lesion was found to contain massive deposits of Thorotrast embedded in a dense fibrotic and sclerotic stroma with focal calcification. These features are typical of "Thorotrastoma." Thorotrast stains greenish-brown with hematoxylin and eosin and appears as refractile granular particles of relatively uniform size either within histiocytes or as free material. The radioactivity of the deposits was confirmed through the use of a scintillation counter, and 232 thorium was definitively identified though the use of scanning electron microscopy with energy-dispersive X-ray analysis. Immunohistochemical studies of the tumor demonstrated glial fibrillary acid protein (GFAP) immunoreactivity in areas of glioma and focal vimentin and actin immunoreactivity in areas of sarcoma. Thorotrast-associated lesions of the central nervous system (CNS) are infrequently reported, and a Thorotrast-associated gliosarcoma has not yet been reported. The use of Thorotrast, its radiobiology, and sequelae are reviewed with particular emphasis on lesions occurring in the CNS.
 ...
PMID:Thorotrast-associated gliosarcoma. Including comments on thorotrast use and review of sequelae with particular reference to lesions of the central nervous system. 328 27


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>