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  • 2000-2004  (1)
  • 1950-1954  (4)
  • 1910-1914
  • 1880-1889
  • Polymer and Materials Science  (4)
  • Apoptosis  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Cancer chemotherapy and pharmacology 45 (2000), S. 183-191 
    ISSN: 1432-0843
    Keywords: Key words Epoxide-containing piperazines ; Apoptosis ; Chemotherapeutics ; AbbreviationsNCO-700 Bis[ethyl(2R,3R)-3-[(S)-3-methyl-1-[4-(2,3,4-trimethoxyphenylmethyl)piperazin-1-ylcarbonyl]butylcarbamoyl]oxirane-2-carboxylate]- sulfate ; TOP-008 Bis[ethyl(2R,3R)-3-[(S)-3-methyl-1-[4(3-phenyl-2-propenyl)piperazin-1-ylcarbonyl]butyl- carbamoyl]oxirane-2-carboxylate]sulfate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: The overall purpose of this study was to determine the potential efficacy of epoxide-containing piperazines as a new class of anti-cancer agents. Two representative compounds, specifically NCO-700, a 4-trimethoxyphenyl-substituted epoxide-piperazine, and TOP-008, a 4-phenylpropenyl-substituted epoxide-piperazine were tested in cytotoxic assays with human breast and prostate cancer cell lines. A second objective was to determine if these two compounds had anti-cancer activity in vivo when tested against xenograft tumors in nude mice or human tumors grown under the kidney capsule in mice. A final objective of this study was to establish if NCO-700 and TOP-008 achieved cancer cell killing through an apoptotic mechanism. Methods: The anti-proliferative activity of NCO-700 and TOP-008 were tested in a 7 day cell-survival assay utilizing a number of well characterized breast (HS-578T, T47D, MCF-7) and prostate (DU-145, PC-3, LNCaP) cancer cell lines. In vivo studies with the two compounds were performed, in nude mice bearing DU-145 xenograft tumors, and in normal mice in which DU-145 prostate cancer cells and HS-578T breast cancer cells were grown as solid tumors in the subrenal capsules of the animals. Apoptotic cell death of cancer cells was determined by a number of established techniques that detect apoptosis, including the confocal laser microscopy of treated cells and mitochondrial leakage assays utilizing the cationic dye, JC-1. Finally, the activation of the caspase cascade, enzymes that carry out apoptosis in mammalian cells, was examined in treated cells by immunoblot assays. Results: NCO-700 and TOP-008 displayed cytotoxicity to HS-578T human breast cancer cells, with ED50 values in the 3–6 μM range. Cytotoxicity to androgen receptor-negative human prostate cancer cells (PC-3 and DU-145 cells) occurred with ED50 values in the 5–20 μM range. Cytotoxicity to hormone receptor-positive breast and prostate cancer cell lines occurred at 10 to 20-fold higher concentrations of the two compounds. When human prostate (DU-145) or breast cancer (HS-578T) cells were grown as solid tumors in the subrenal capsules of mice, significant anti-tumor activity of NCO-700 was observed at 20 mg/kg and 50 mg/kg body weight respectively, for prostate and breast tumors. In nude mice bearing DU-145 prostate tumor xenografts, 50 mg/kg doses of the two compounds either stopped (TOP-008) tumor growth or slowed (NCO-700) growth. The mechanism of cytotoxicity was shown to be through apoptosis, (a) by confocal microscopy studies revealing nuclear fragmentation, (b) by mitochondrial studies revealing disruption of the mitochondrial membrane and release of the cationic dye, JC-1, into the cytoplasm and (c) by protein immunoblot assays indicating that over a 6 h period, TOP-008 induced a significant accumulation of the pro-apoptotic protein, bak, in the mitochondrial fraction of HS-578T human breast cancer cells, accompanied by activation, at 2.5 h, of caspase-3. Conclusions: These studies indicated that the epoxide-containing piperazines, as exemplified by NCO-700 and TOP-008, were effective anti-cancer agents when tested in vitro and in vivo against human breast and prostate tumors. Our studies also indicated that TOP-008 induced the initiation of the caspase cascade leading to apoptosis. Previous toxicology studies in rodents and dogs, as well as a Phase I study in humans, showed NCO-700 to be a well-tolerated, non-toxic compound. Taken together with our current findings, these results suggest that this class of compounds has the potential to be relatively safe, new chemotherapeutic agents for refractory breast and prostate cancers.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 11 (1953), S. 447-454 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A simple and inexpensive instrument for measuring the osmotic pressure of polymer solutions has been designed. It consists of two 1-mm. I. D. Pyrex capillary tubes sealed into a flanged Pyrex sleeve, which is ground to fit snugly into a 19 × 60 mm. roundbased Alundum Thimble of medium porosity. A regenerated cellulose membrane is cast over the Alundum thimble, and the entire assembly is sealed in a test tube containing the polymer solution to be examined. This osmometer offers several unique advantages over others in current use. Its low cost and compact size permit inexpensive simultaneous measurement of many polymer solutions.A 1:3 copolymer of vinyltoluene and styrene monomers was separated into 24 cuts by fractional precipitation. On the basis of viscosity data these cuts were combined into 14 fractions. They were in the order of decreasing molecular weight, and infrared analysis indicated a uniform distribution of the ring methyl groups among the fractions. These two observations demonstrate that introduction of methyl groups into the benzene rings of a polystyrene molecule does not influence the polymer solubility appreciably.Osmotic molecular weights obtained with the Alundum thimble instruments and experimental limiting viscosity numbers gave values of 2.69 × 10-4 and 0.622 for K and α respectively in the Flory-Staudinger relation [η] = KMα. These results compare favorably with reported values for polystyrene samples prepared under similar conditions.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 9 (1952), S. 93-95 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 7 (1951), S. 159-173 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Butadiene-styrene copolymers have been prepared at subfreezing temperatures by means of redox recipes employing inorganic salts as freezing point depressants. Specific salt-emulsifier combinations are required for optimum rates of polymerizations. With a sufficient amount of the inorganic salt to lower the freezing point of water 10°C., the sodium chloride-potassium caprylate combination resulted in a 60% conversion in 4.6 hours, the calcium chloride-sodium hexyl sulfate combination resulted in a 41% conversion in 24 hours, and the calcium chloride-alkyl aryl polyether alcohol combination resulted in a 58% conversion in 18.5 hours.Low molecular weight mercaptans such as tert-butyl mercaptan can be employed as practical modifiers for this recipe.Certain of the physical properties of the salt antifreeze copolymers prepared at -10°C. are superior to those of copolymers prepared at the same temperature by means of conventional recipes. The ease of processing and the heat-aged properties are exceptional. One copolymer after 24 hours of aging at 100°C. withstood 118,000 flexures before a puncture increased to one inch in length at 99°C. The superiority of the product is attributed to the precipitation of the copolymer during the course of the polymerization.
    Additional Material: 10 Tab.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 7 (1951), S. 289-324 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
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