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  • 1
    ISSN: 1433-0350
    Keywords: Malignant astrocytoma ; Glioblastoma ; Cerebellum ; Children ; Cytofluorometric DNA analysis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The case of a 1-year-old girl with primary malignant astrocytoma of the cerebellum is presented with special reference to ultramicroscopic study and cytofluorometric DNA analysis. The routine light microscopic study was not pathognomonic because of the immaturity of the composing cells. The glial fibrillary microfilaments characteristic of astroglial cells were confirmed by means of electron microscopy. Cytofluorometrically, the DNA histogram of this case revealed a prominent peak in the 4C region, with considerable dispersion to the 8C region, indicating the polyploidic and heterogeneic pattern of malignant tumors.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1573-7373
    Keywords: brain tumor ; (14C-methyl)-L-methionine ; cycloheximide ; protein synthesis ; autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Autoradiographic study of (14C-methyl)-L-methionine with brain tumor bearing rats aimed at an elucidation of the mechanism of tracer accumulation in the protein synthesis of tumor. Twice as much tracer accumulated in the tumors compared as in the contralateral gray matter (nontumor region) at 90 min post intravenous injection. The protein-bound fraction of the tumors, expressed as acid-insoluble fraction (AIF), was 1.7 ± 0.6 (mean ± standard deviation, n=6), significantly higher than that (0.8 ± 0.2) of the nontumor region (p〈0.05 by the Mann-Whitney test). The tumor AIF comprised 82.3 ± 9.2% of the total amount of the tracers accumulated in the tumors. The protein synthesis inhibitor cycloheximide reduced the tracer uptake and the AIF of the tumors to an almost same level as the nontumor region. These findings indicate that metabolic acceleration of protein synthesis may be a main reason for the high accumulation of (14C-methyl)-L-methionine in tumor.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1573-7373
    Keywords: positron emission tomography (PET) ; glioma ; glucose metabolism ; hemocirculation ; radiation therapy ; chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Hemocirculatory and metabolic changes in tumor regions and the remote brain structure were analyzed using oxygen-15 and fluorine-18 positron emission tomography (PET) in eight patients with gliomas after radiation and chemotherapy of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) and N-(2-tetrahydrofuryl)-5-fluorouracil (FT 207). In the tumor regions after the radiochemotherapy, regional cerebral blood flow (rCBF) and cerebral blood volume (rCBV) varied widely and there was a tendency for oxygen consumption (rCMRO2) to fall. The change in glucose consumption (rCMRGI) was especially noteworthy with regard to clinical correlations. Six patients with decreased rCMRGI values had 16010 to 29010 regressions in tumor size measured by X-ray computerized tomography (CT), and showed some period of clinical relief. In contrast, one patient with an increased rCMRGI value had some progression of tumor growth, and there were no clinical amelioration. The hemocirculation and metabolism of the contralateral gray matter seem to fluctuate by various factors as intracranial pressure and the effectiveness of the therapy. In gliomas therapy, tumor rCMRGI values can be a good indicator of therapeutic effectiveness.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1573-7373
    Keywords: brain tumor ; recombinant human tumor necrosis factor-α ; blood flow ; methionine uptake ; autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The aim of the present study is tounderstand the therapeutic effects of recombinant human tumornecrosis factor-α (rH-TNF) on hemocirculation and metabolism ofbrain tumors. Using double-label autoradiographic technique, we havemonitored changes in regional cerebral blood flow (rCBF)and protein-bound fraction of (3H-methyl)-L-methionine, expressed as acid-insolublefraction (AIF), in rat brain tumors following treatmentwith intracarotid rH-TNF. The central portion of tumorsshowed a significant decrease in rCBF and AIFat 4 hours after the injection (p 〈0.01, p 〈 0.05, respectively, as compared withnon-treated control rats), turned microscopically necrotic at 24hours, and became more extensively necrotic at 72hours. Tumor cells remained viable only in theperipheral portion of the tumors after the treatment.The peripheral portion also showed a moderate decreasein rCBF, but less change in AIF to4 to 72 hours after the treatment. Neitheripsilateral nor contralateral non-involved cortex demonstrated appreciable changesin rCBF and AIF during the observed period.Intracarotid rH-TNF selectively reduces tumor rCBF and AIF,resulting in histological modification.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1573-7373
    Keywords: 18F-fluorodeoxyglucose ; kinetic analysis ; oligodendroglioma ; positron emission tomography ; tumor recurrence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To accurately characterize the pathophysiology and proliferating activity of oligodendrogliomas, we studied cerebral blood flow and metabolism using positron emission tomography (PET) in five patients with this tumor. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), oxygen extraction fraction (rOEF), and cerebral metabolic rates of oxygen (rCMRO2) and of glucose (rCMRGl) were quantitatively measured in tumor lesions and the contralateral gray matter. rCMRGl was analyzed based on both kinetic and autoradiographic methods. Tumor rCBF and rCBV were lower than in the contralateral gray matter in all preoperatively examined patients. Oxygen metabolism, determined by rCMRO2 and rOEF, was consistently reduced in the tumor (rCMRO2, P〈0.05 vs. gray matter, determined by the Student's t-test). Tumor rCMRGl was significantly lower than the gray matter rCMRGl in both kinetic (P〈0.01) and autoradiographic (P〈0.05) analyses. Kinetic tumor rCMRGl varied between 1.22 and 4.13 mg/100 ml/min, but was lower than the gray matter value in all patients. Autoradiographic tumor rCMRGl, which ranged from 1.02 to 5.79 mg/100 ml/min, was also reduced in all tumors but one; the remaining tumor, which had a relatively high value of autoradiographic rCMRGl (comparable to gray matter rCMRGl), infiltrated the contralateral hemisphere through the corpus callosum, and was characterized by high cellular density. In one patient who suffered from tumor recurrence 8 years and 10 months after initial treatment, phosphorylation constant (K3) and kinetic rCMRGl of the recurring tumor were higher than those of the original tumor. No other tumors have regrown or recurred during the postoperative follow-up periods, which ranged from 22 to 130 months (median=101 months). Circulation and metabolism measured by PET provide in vivo biological characteristics, including proliferating activity, in oligodendrogliomas.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1573-7373
    Keywords: brain tumors ; intracarotid administration ; ACNU ; BUdR labeling index
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Chloroethy1nitrosourea (CENU) chemotherapy has yielded limited benefit on survival of malignant brain tumors. Intracarotid administration of CENU is expected to have the advantage of increasing drug concentration reaching tumors. To understand basic knowledge of intracarotid chemotherapy, we monitor changes of proliferating rate after intracarotid injection of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2chloroethyl)-3-nitrosourea hydrochloride (ACNU), using a bromodeoxyuridine (BUdR) labeling index (LI) in transplanted brain tumors of three cell strains. C6-2 tumor cells were in vitro sensitive to ACNU, and C6-2/ACNU and C6-1 cells were resistant. The drug sensitivity to ACNU was as follows: 11.9 μtM in the C6-2 cells, 46.0 μM in the C6-2/ACNU cells, and 49.7 μM in the C6-1 cells at SD10, which gives 10% survival of clonogenic cells. The intracarotid ACNU at a dose of 30 mg/kg abruptly decreased the LI to 11% (mean) from 36% in C6-2 transplanted tumors. The LI remained low between 12 and 48 hours after, and then increased to the pretreatment level by 96 hours. In contrast, the LI of C6-1 tumors transiently fell to 15% from 42% at 12 hours after the injection, and subsequently increased to 36% at 24 hours and 37% at 48 hours. These results indicate that intracarotid ACNU administration shortly suppresses proliferating activity of tumors and that combined and alternating chemotherapy are mandatory for enhancing effectiveness of brain tumor chemotherapy.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1573-7373
    Keywords: subependymoma ; positron emission tomography ; 18F-fluorodeoxyglucose
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report the evaluation of a subependymoma of the septum pellucidum by positron emission tomography (PET) with analysis of 18F-fluorodeoxyglucose (FDG)kinetics. The tumor showed exceedingly low rates of glucose metabolism (rCMRG1) and kinetic constants (K1, K2, and K3). This hypometabolism indicates low cellular density and slow growth.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1573-7373
    Keywords: glioma ; cell line ; establishment ; cloroethylnitrosourea ; chemosensitivity ; O6-methylguanine-DNA methyltransferase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have characterized two human glioblastoma cell lines, which were designated as YH cells and AM cells. The two cell lines maintained morphological appearance observed in the primary culture and immunohis-tochemically expressed glial fibrillary acidic protein (GFAP) and S-100 protein. Population doubling time for YH cells and AM cells indicated 30 hours and 25 hours, respectively, in an exponential phase of culture. Inoculation of AM cells into athymic nude mice formed large tumors at a high incidence. As with chemo-sensitivity to chloroethylnitrosourea, O6-methylguanine-DNA methyltransferase (MGMT) activity was measured inin vitro cultured cells as well as tumor specimens obtained at surgery. YH cells showed a high MGMT activity of 1196 fmol/mg and drug resistance to 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-cloroethyl)-3-nitrosourea hydrochloride (ACNU) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. YH tumor specimens indicated an MGMT activity of 301 fmol/mg, which reflected poor effectiveness of ACNU chemotherapy in the clinical evaluation. AM cells had an extremely low MGMT activity of 16 fmol/mg and were vulnerable to ACNU. Original tumor specimens of AM cells however expressed a high value of 628 fmol/mg. Considering that ACNU chemotherapy was not effective in the both patients, an MGMT activity of original tumors related with responsiveness to ACNU. Discrepancy in an MGMT activity between thein vitro cell lines and the respective tumor specimens comes from selection of ACNU-sensitive cells or alteration in biological characteristics during long term culture. These results suggest that cell lines derived human brain tumors are useful targets for understanding the chemosensitivity of human malignant gliomas and for establishing a pertinent chemosensitivity test.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1573-7373
    Keywords: malignant glioma ; recombinant human tumor necrosis factor-α ; positron emission tomography ; hemocirculation ; glucose metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cerebral hemocirculation and glucose metabolism in a malignant astrocytoma were repeatedly quantified before and after intracarotid injection of recombinant human tumor necrosis factor-α (rH-TNF) using positron emission tomography (PET). The patient received an intracarotid injection of a 3 × 104 U/m2 dose of rH-TNF three times over a two week period. PET was performed prior to and 24 hr after the first injection, and two weeks after the third injection. Prior to the first rH-TNF treatment, two lesions demonstrating high perfusion and hypermetabolism of glucose were noted in the right frontal and temporal regions. The frontal hypermetabolic lesion showed decreases in hemocirculation and metabolism 24 hr after the first injection and then increases beyond the pre-treatment level two weeks after the third treatment, whereas the temporal lesion remained unchanged during the follow-up period. No appreciable changes were noted in the adjacent cortex where rH-TNF was perfused, with the exception of a transient decrease in regional blood volume. Magnetic resonance images of the tumor showed no changes as a result of treatment with intracarotid rH-TNF. Intracarotid rH-TNF preferentially affects tumor tissue as opposed to normal cortex.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1573-7373
    Keywords: central nervous system ; lymphoma ; T-cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Primary central nervous system (CNS) involvement of non-Hodgkin's lymphoma is uncommon and a vast majority of reported cases are of B-cell origin. We present a 52-year-old woman with primary peripheral T-cell lymphoma of the brain. Immunostaining of paraffin-embedded sections proved tumor cells to be positive for T-cell markers MT1 and UCHL1, and negative for B-cell markers MB1, and 4KB5. Radiotherapy combined with steroid therapy rendered neurologic recovery and complete tumor remission confirmed by computed tomography and magnetic resonance imaging. From a review of documented 19 cases of primary CNS T-cell lymphoma including the present case, this disease is characterized by poor prognosis among CNS lymphomas.
    Type of Medium: Electronic Resource
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