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

A reversed-phase high-performance liquid chromatographic (HPLC) assay was developed for the antitumor anthrapyrazole analogue, oxantrazole (OX), in rat whole blood and tissues. Blood samples were mixed with equal volumes of a 25% (w/v) aqueous solution of L-ascorbic acid, whereas tissue samples were homogenized with 1.5-3 volumes of an L-ascorbic acid-methanol-water (1:10:1, w/v/v) mixture to prevent oxidative degradation of OX. Samples were then treated with 60% (v/v) perchloric acid (25-30 microliters/ml of stabilized sample) to precipitate proteins, and centrifuged, with the resultant supernatants analyzed on HPLC utilizing a C8 column. The mobile phase for blood and urine samples consisted of 8% (v/v) glacial acetic acid, 13% (v/v) acetonitrile, 79% (v/v) water, 0.16% (w/v) sodium acetate, and 0.05% (w/v) L-ascorbic acid (final pH 2.7), and was pumped at 1.8 ml/min. Tissue samples were eluted at 2 ml/min with a mobile phase consisting of 8% (v/v) glacial acetic acid, 12% (v/v) acetonitrile, 80% (v/v) water, 0.16% (w/v) sodium acetate, and 0.0;5% (w/v) L-ascorbic acid. OX and internal standard were detected at 514 nm and had retention times of 2.3 and 3.1 min, respectively. The limit of quantitation of OX was 25-50 ng/g. Recovery of OX from biological samples ranged from 50 +/- 0.9% in spleen to 102.8 +/- 1.8% in RG-2 glioma. The analytical method was applied to a pharmacokinetic study in rats.
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PMID:High-performance liquid chromatographic analysis of the anticancer drug oxantrazole in rat whole blood and tissues. 149 Oct 45

Physicochemical characteristics of monocyte chemotactic activity in the culture fluid of PHA-stimulated human mononuclear leukocytes (MNL) were investigated. Among several chemotactic activity peaks eluted from a TSK-2000 gel filtration column, one peak, corresponding to a molecular mass of 17 kDa, accounted for about 40% of total chemotactic activity. On a chromatofocusing column, most of the 17-kDa activity eluted in a pH range of 9.4 to 7.9. It could bind to Orange-A Sepharose. These three characteristics--molecular mass, basic isoelectric point, and dye column binding--were similar to those of human glioma-derived monocyte chemotactic factor (GDCF), recently purified in our laboratory. Therefore, the MNL-derived chemoattractant was purified by the same procedures used for purification of GDCF, namely Orange-A Sepharose chromatography, carboxymethyl (CM)-HPLC, and reverse phase (RP) HPLC. About 50% of the culture fluid chemotactic activity bound to Orange-A Sepharose and was eluted in a single peak by a NaCl gradient. The active pool from the Orange-A column was separated into two sharp peaks by CM-HPLC, each of which eluted at identical acetonitrile concentrations from a RP HPLC column. By SDS-PAGE, the peptides had apparent molecular masses of 15 and 13 kDa and appeared homogeneous. Amino acid analysis showed that the composition of the two peptides was almost identical; and the N terminus of each peptide was apparently blocked. Shared characteristics of these peptides and the GDCF peptides include identical elution patterns from CM- and RP HPLC columns, identical SDS-PAGE migration, almost identical amino acid composition, and blocked N terminus. This suggests that the monocyte attractants isolated from culture fluid of PHA-stimulated MNL are identical to those derived from human glioma cells.
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PMID:Purification and amino acid analysis of two human monocyte chemoattractants produced by phytohemagglutinin-stimulated human blood mononuclear leukocytes. 292 21

The potential for differentiation of the human basophilic leukaemia cell line KU812 was examined by means of a panel of physiologic and non-physiologic substances used as inducers. The phenotypic characteristics of non-induced KU812 cells included an immature morphology with scanty cytoplasmic granulation, expression of a low amount of high affinity, but no low affinity receptors (CD 23) for IgE, and a capacity for low-rate histamine synthesis. The differentiation process was characterized by a rapid (24 h) increase in histamine production a slower morphological maturation with the development of Alcian blue stainable granula demonstrable after 72 h. Concomitant with the phenotypic alterations, cell growth was inhibited. Differentiation in KU812 cells was inducible by Ara-C and to some extent by sodium butyrate, but not by dimethyl sulphoxide, retinoic acid, or gamma-interferon. Conditioned medium (CM) from cultured peripheral blood cells from atopic individuals and 18 out of 22 analysed glioma cell lines induced differentiation of the KU812 cells, whereas supernatant from only 1 out of 21 other cell lines, including carcinoma, melanoma, sarcoma, leukaemia, and normal fibroblasts had this activity. CM from the T-leukaemic cell line, Mo, also induced KU812 differentiation. A primary fractionation of the active substance from this cell line by reversed phase chromatography eluted the active substance at a concentration of 42-44% acetonitrile. Our present study has shown that the KU812 may serve as an appropriate model to study differentiation of basophils. In addition, its fast and specific response to biological factors makes it suitable as a biological assay for determination of active factor produced by atopic individuals.
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PMID:Induction of basophilic differentiation in the human basophilic cell line KU812. 297 55

Progression to increased malignancy frequently occurs in human brain tumors of glial origin and usually involves neovascularization--a massive proliferation of endothelial cells into the tumor tissue. We have shown previously that subversion of a normal growth factor-related pathway is frequently associated with human gliomas. Here we show that human glioma cell lines express the gene encoding the angiogenic peptide endothelial cell growth factor (ECGF) or acidic fibroblast growth factor (a-FGF) and that an ECGF-like polypeptide is produced by these cells. The glioma-derived growth factor was partially purified from cell extracts by heparin-Sepharose affinity chromatography where it eluted at 1.5 M sodium chloride. On reversed-phase h.p.l.c., growth factor activity for endothelial cells was eluted at the same concentration of acetonitrile as found for bovine brain-ECGF, also a potent mitogen for endothelial cells. Moreover, human glioma cells possess specific cell surface receptors for ECGF and are mitogenically stimulated by exogenous addition of this growth factor. Glioma derived-ECGF may therefore have a dual influence: first, by autocrine growth-stimulation of human gliomas and, second, by paracrine-stimulation of endothelial cell proliferation which results in neovascularization of the tumor tissue.
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PMID:An angiogenic growth factor is expressed in human glioma cells. 330 30

A method for purification of astroprotein (an astrocyte-specific cerebroprotein) with HPLC is described. A linear gradient from 30 to 70% acetonitrile in 0.1% trifluoroacetic acid (pH 2.2) was applied to the reversed-phase C-1 (particle size 10 micron) column. Cerebroproteins from the crude extract from human glioma were clearly separated by this procedure. Highly purified astroprotein was homogeneous by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and has immunoreactivity to antiserum against astroprotein. Reversed-phase C-1 HPLC offers advantages over previously available preparative techniques in the higher purity and better separation time of the products.
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PMID:Purification of astroprotein (astrocyte-specific cerebroprotein) by reversed-phase C-1 HPLC. 391 54

We have shown that several human malignant glioma cell lines are stimulated by bacterial lipopolysaccharide (E. coli 0111:B4, 1 microgram/ml) to produce a high molecular weight (> 200 kD) growth activity for BALB 3T3, clone A31 cells. This glioma-derived growth factor (GDGF-2) acts like a 'competence' factor. Malignant glioma cell line D-54 MG constitutively produced GDGF-2, which we have partially characterized from serum-free conditioned culture medium. GDGF-2 is resistant to heat (100 degrees C, 5 min), acidic (pH 2, 2 hr) or reducing (0.5 M 2 ME, 30 min) conditions as well as exposure to RNases; however, it is sensitive to > 4 freeze-thaw cycles, alkaline (pH 11, 2 hr) conditions or pre-treatment with proteolytic enzymes. GDGF-2 had a pl of 6.8 determined by preparative isoelectric focusing, bound to DEAE, with elution at 35 and 185 mM NaCl and at 43% acetonitrile from a C4 reversed phase column. GDGF-2 activity was not neutralized by antibodies to TGF alpha, TGF beta, PDGF, VEGF or TNF alpha indicating that it is not immunochemically related to these growth factors. However GDGF-2 co-chromatographed on Superose 12 HPLC (250 x 9 mm; 5% isopropanol, 6 mM CHAPS in PBS) with a substance that suppressed growth of mink lung epithelial cells (Mv1Lu), but not BALB 3T3 cells, and could be neutralized by anti-TGF beta antibodies. GDGF-2 activity eluted from heparin columns in 0.6 M NaCl; thus, it is not a heparin binding growth factor. D-54 MG cell line produced alpha 2-macroglobulin (alpha 2M), which is known to bind TGF beta; however, immunoprecipitation of alpha 2M did not deplete TGF beta or GDGF-2 activity. Further, neither GDGF-2 or TGF beta can be dissociated into lower molecular weight active components by chromatography in high salt (2 M NaCl) or 2-ME (0.5 M). GDGF-2 may be a novel autocrine or paracrine mitogen, stimulating mitotic division or interfering with normal cell growth regulation.
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PMID:Partial characterization of glioma-derived growth factor 2: a novel mitogenic activity from human cell line D-54 MG. 814 64

Several monoclonal antibodies (mAb) reactive against a high-molecular-weight growth factor from human glioblastoma cell lines have been produced by immunizing mice with partially purified preparations from conditioned media. Antibody-secreting colonies were selected by their capacity to bind 35S-labeled glioma cell protein and by reactivity in indirect enzyme-linked immunoadsorbent assay (ELISA), using high-molecular-weight gel filtration fractions and preparative isoelectric focusing fractions containing growth factor activities. Two of the select mAbs (20F3 and 12A12) depleted mitogenic activity (> 50% inhibition, p < 0.05) from gel filtration fractions by immunoprecipitation, but could not neutralize mitogenic activity directly. Mitogenic activity recovered from affinity columns prepared with mAb 20F3 eluted at 48% and 52% acetonitrile from HPLC C4 reversed-phase columns. Immunoprecipitation of 35S-labeled cell lysates with 20F3 followed by resolution with SDS-PAGE autoradiography revealed one unique protein of 170 kD. Established glioma cell line D-54 MG showed perinuclear and cytoplasmic staining with mAb 20F3. mAb 20F3 should prove useful in purification and characterization of these glioma-derived growth factor(s).
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PMID:Monoclonal antibodies to glioma-derived growth factor(s). 820 Jun 54

Detailed biological studies of methyl- and some ethylimidazolium ionic liquids in luminescent bacteria as well as in the IPC-81 (leukemia cells) and C6 (glioma cells) rat cell lines are presented. Effective concentrations in these test systems are generally some orders of magnitude lower than effective concentrations [corrected] of the conventional solvents acetone, acetonitrile, methanol, and methyl t-butyl ether. No general influence of the anionic compound in the ionic liquids on toxicity could be found, although they seem to modulate toxicity in some cases. The clear influence of the alkyl chain length on toxicity was quantified by linear regression analysis. Alkyl chain length of the longer alkyl chain was varied from 3 to 10 carbon atoms. Consequences for a design of sustainable alternative solvents are briefly sketched.
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PMID:Biological effects of imidazolium ionic liquids with varying chain lengths in acute Vibrio fischeri and WST-1 cell viability assays. 1522 65

We hereby report the synthesis of four fluorine-18 labeled tyrosine derivatives, 3-(2-[(18)F]fluoroethyl)tyrosine ([(18)F]1, [(18)F]ortho-FET), 3-(3-[(18)F]fluoropropyl)tyrosine ([(18)F]2, [(18)F]ortho-FPT) O-methyl-[3-(2-[(18)F]fluoroethyl)]tyrosine ([(18)F]3, [(18)F]MFET), and O-methyl-[3-(3-[(18)F]fluoropropyl)]tyrosine ([(18)F]4, [(18)F]MFPT). The fluorine-18 labeled tyrosine derivatives were prepared by the displacement reaction of the ethyl and propyl tosylates with K[(18)F]/K2.2.2 in acetonitrile under no-carrier-added (NCA) conditions, followed by hydrolysis with 4N HCl. The biological properties of labeled compounds were evaluated in rats bearing 9L tumor after an intravenous injection and PET image was obtained. The tumor/blood and tumor/brain ratios were 2.06, 2.92 for [(18)F]1, 2.25, 4.05 for [(18)F]2, 2.88, 1.90 for [(18)F]3, and 2.00, 2.60 for [(18)F]4 at 60 min post injection, respectively. The PET image showed localized accumulation of PET tracers in 9L glioma of the rat.
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PMID:Syntheses of F-18 labeled fluoroalkyltyrosine derivatives and their biological evaluation in rat bearing 9L tumor. 1703 15

Curcumin, a lipophilic polyphenol derived from the rhizome of the plant turmeric (Curcuma longa), might be useful in the prevention and treatment of a number of degenerative brain disorders, including glioma multiforma and Alzheimer's disease. Thus, there is growing interest in measuring curcumin concentrations in the brain and other target tissues in relevant animal models. We therefore developed and validated (according to the Food and Drug Administration guidelines for bioanalytical method validation), a simple, fast and reliable method for the quantification of curcumin in biological matrices by fast high-performance liquid chromatography with fluorescence detection. This method involves a simple extraction with 95% ethyl acetate and 5% methanol, rapid separation (<2 min if external standards and <4 min if the internal standard beta-estradiol 17-acetate is used) on a Jasco Reprosil-Pur Basic C(18) column (75 x 2 mm, 1.8 mum) with an eluent of acetonitrile, methanol, de-ionised water and acetic acid (49:20:30:1, v/v; flow rate, 0.4 mL/min) and fluorescence detection (excitation wavelength, 420 nm; emission wavelength, 470 nm). The method is selective, precise (<15% RSD at the lower limit of quantification), accurate (<15% of the coefficient of variation at the lower limit of quantification) and sensitive over a linear range of 0.05-10 microg/mL for curcumin. The developed method was used for the quantification of curcumin in the brains of mice force-fed (50 mg/kg bw) or i.p. injected (100 mg/kg bw) with curcumin. Brain curcumin concentrations of the mice were below the limit of detection at 30, 60 and 120 min after oral gavage and reached 4-5 microg/g brain 20-40 min after i.p. injection. In conclusion, the developed and validated method should be useful for the accurate and precise quantification of curcumin in target organs from relevant animal models of human diseases.
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PMID:A validated method for the quantification of curcumin in plasma and brain tissue by fast narrow-bore high-performance liquid chromatography with fluorescence detection. 2041 5


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