Search results for "plastic"
showing 10 items of 7296 documents
Acetaldehyde, motivation and stress: Behavioral evidence of an addictive ménage à trois
2017
Acetaldehyde contributes to alcohol’s psychoactive effects through its own rewarding properties. Recent studies shed light on the behavioral correlates of acetaldehyde administration and the possible interactions with key neurotransmitters for motivation, reward and stress-related response, such as dopamine and endocannabinoids. This mini review critically examines acetaldehyde psychoactive properties, focusing on behavioral investigations able to unveil acetaldehyde motivational effects and their pharmacological modulation in vivo. Similarly to alcohol, rats spontaneously drink acetaldehyde, whose presence is detected in the brain following chronic self-administration paradigm. Acetaldehyd…
Differential changes in purine nucleotides after Doxorubicin treatment of human cancer cells in vitro
2002
The present investigation was performed to elucidate the role of purine nucleotides as potential indicators of chemosensitivity of malignant tumors. Drug-sensitive (s) and -resistant (r) tumor cell lines grown as monolayers (s: T47D, MCF-7 wild-type; r: NCI/ADR-RES, MCF-7/MDR) or as multicellular spheroids (T47D; NCI/ADR-RES) were exposed to 0.1, 1.0, and 10.0 microM Doxorubicin for up to 24 h. Purine nucleotides were assayed using HPLC and with some selected spheroids using imaging bioluminescence. The data show that in the time frame of the experiments reproducible and statistically significant changes in the nucleotides only occur at the highest drug concentration investigated. Under the…
Novel ruthenium methylcyclopentadienyl complex bearing a bipyridine perfluorinated ligand shows strong activity towards colorectal cancer cells
2017
Three new compounds have been synthesized and completely characterized by analytical and spectroscopic techniques. The new bipyridine-perfluorinated ligand L1 and the new organometallic complex [Ru(η 5 -MeCp)(PPh 3 ) 2 Cl] (Ru1) crystalize in the centrosymmetric triclinic space group P1¯. Analysis of the phenotypic effects induced by both organometallic complexes Ru1 and [Ru(η 5 -MeCp)(PPh 3 )(L1)][CF 3 SO 3 ] (Ru2), on human colorectal cancer cells (SW480 and RKO) survival, showed that Ru2 has a potent anti-proliferative activity, 4–6 times higher than cisplatin, and induce apoptosis in these cells. Data obtained in a noncancerous cell line derived from normal colon epithelial cells (NCM46…
Anti-proliferative and pro-apoptotic activity of whole extract and isolated indicaxanthin from Opuntia ficus-indica associated with re-activation of …
2014
Phytochemicals may exert chemo-preventive effects on cells of the gastro-intestinal tract by modulating epigenome-regulated gene expression. The effect of the aqueous extract from the edible fruit of Opuntia ficus-indica (OFI extract), and of its betalain pigment indicaxanthin (Ind), on proliferation of human colon cancer Caco-2 cells has been investigated. Whole extract and Ind caused a dose-dependent apoptosis of proliferating cells at nutritionally relevant amounts, with IC50 400 ± 25 mg fresh pulp equivalents/mL, and 115 ± 15 μM (n = 9), respectively, without toxicity for post-confluent differentiated cells. Ind accounted for ∼80% of the effect of the whole extract. Ind did not cause ox…
Synthesis, antiproliferative activity, and mechanism of action of a series of 2-{[2E]-3-phenylprop-2-enoylamino}benzamides
2011
Several new 2-{[(2E)-3-phenylprop-2-enoyl]amino}benzamides 12a–s and 17t–v were synthesized by stirring in pyridine the (E)-3-(2-R1-3-R2-4-R3-phenyl)acrylic acid chlorides 11c–k and 11t–v with the appropriate anthranilamide derivatives 10a–c or the 5-iodoanthranilic acid 13. Some of the synthesized compounds were evaluated for their in vitro antiproliferative activity against the full NCI tumor cell line panel derived from nine clinically isolated cancer types (leukemia, non-small cell lung, colon, CNS, melanoma, ovarian, renal, prostate and breast). COMPARE analysis, effects on tubulin polymerization in cells and with purified tubulin, and effects on cell cycle distribution for 17t, the mo…
Synthesis and preliminary biological evaluation of a new pyridocarbazole derivative covalently linked to a thymidine nucleoside as a potential target…
2003
The therapy of human cancer is one of the more pursued goals by medicinal chemistry research. Most of the compounds clinically used as a treatment owe their efficacy to their cytotoxic interaction (direct or indirect) with nuclear DNA. This interaction results in the inhibition of DNA synthesis and the degradation of nucleic strands. Ellipticine is a naturally occurring 6H-pyrido[4,3-b]carbazole alkaloid endowed with antitumor activity, and several ellipticine derivatives have been used in clinical trials. We previously reported some 1,4-dimethyl-9H-carbazole derivatives structurally related to ellipticine. The purpose of our research was to transform the pyridocarbazole in a prodrug so tha…
An unexpected Dimroth rearrangement leading to annelated thieno[3,2-d][1,2,3]triazolo[1,5-a]pyrimidines with potent antitumor activity.
2013
An unusual Dimroth rearrangement occurring in the reaction leading to annelated thieno[2,3-e][1,2,3]triazolo[1,5-a]pyrimidine core allowed the isolation of the linear isomer thieno[3,2-d][1,2,3]triazolo[1,5-a]pyrimidine. By decorating the linear isomer with the same chains that improved the biological activity of the angular isomers, new annelated thieno[3,2-d][1,2,3]triazolo[1,5-a]pyrimidines were designed and synthesized. They were selected by the Developmental Therapeutics Program (DTP) of the National Cancer Institute (NCI) for the anticancer screening against a panel of 60 human tumor cell lines. The biological results showed that the new derivatives exhibited strong antiproliferative …
New annelated thieno[2,3-e][1,2,3]triazolo[1,5-a]pyrimidines, with potent anticancer activity, designed through VLAK protocol
2012
Drug design was performed through the Virtual Lock-and-Key (VLAK) protocol. This in silico approach allowed to select new annelated thienotriazolopyrimidine derivatives, potentially antitumor drugs. Starting from benzothieno[2,3-e][1,2,3]triazolo[1,5-a]pyrimidine and Pyrido[3',2':4,5]thieno[2,3-e][1,2,3]triazolo[1,5-a]pyrimidine core structures, new derivatives of these nuclei were designed and synthesized. Three of them were selected by the Development Therapeutical Program (DTP) of the National Cancer Institute (NCI) for the anticancer screening against a panel of 60 human tumor cell lines. The biological results showed that the new derivatives exhibited an excellent antiproliferative act…
[Clinical guidelines for the management of gastrointestinal stromal tumors]
2006
Treatment of gastrointestinal stromal tumors (GIST) has been revolutioned by the recently discovered molecular mechanism responsible for the oncogenesis of this disease. In addition, due to the rapid progress at molecular and clinical level observed in the last few years, there is a need to review the current state of the art in order to delineate appropriate guidelines for the optimal management of these tumors. A panel of experts from several specialities, including medical oncology, surgery, pathology, molecular biology and imaging, were invited to participate in a meeting to present and discuss a number of pre-selected questions, and to achieve a consensus according to the categories of…
Is the repair of oxidative DNA base modifications inducible by a preceding DNA damage induction?
2007
In mammalian cells, 7,8-dihydro-8-oxoguanine (8-oxoG) and some other oxidative guanine modifications are removed from the DNA by base excision repair, which is initiated by OGG1 protein. We have tested whether this repair is inducible in mouse embryonic fibroblasts (MEFs), MCF-7 breast cancer cells and primary human fibroblasts by a pretreatment with the photosensitizer Ro19-8022 plus light, which generates predominantly 8-oxoG, or with methyl methanesulfonate (MMS), which generates alkylated bases and abasic sites (AP sites). The results indicate that the repair rate of the oxidative guanine modifications induced by the photosensitizer was not increased if a priming dose of the oxidative o…