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Mauro C. X. Pinto Betania B. Cota Michele A. Rodrigues Maria F. Leite Elaine M. de Souza‐Fagundes 《Journal of biochemical and molecular toxicology》2013,27(11):479-485
Hypnophilin (HNP) is a sesquiterpene that is isolated from Lentinus cf. strigosus and has cytotoxic activities. Here, we studied the calcium signaling and cytotoxic effects of HNP in UACC‐62 cells, a human skin melanoma cell line. HNP was able to increase the intracellular calcium concentration in UACC‐62 cells, which was blocked in cells stimulated in Ca2+‐free media. HNP treatment with BAPTA‐AM, an intracellular Ca2+ chelator, caused an increase in calcium signals. HNP showed cytotoxicity against UACC‐62 cells in which it induced DNA fragmentation and morphological alterations, including changes in the nuclear chromatin profile and increased cytoplasmatic vacuolization, but it had no effect on the plasma membrane integrity. These data suggest that cytotoxicity in UACC‐62 cells, after treatment with HNP, is associated with Ca2+ influx. Together, these findings suggest that HNP is a relevant tool for the further investigation of new anticancer approaches. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:479‐485, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21507 相似文献
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Abstract The lipidic component of Citrus limon (L.) Burm. stigmatic exudate. Chromatographic methods (Gas Chromatography and Thin Layer Chromatography) were used to investigate the lipids present in the stigmatic secretion of Citrus limon. 12 fatty acids, ranging from C 12 to C 24, were identified; they form 7 classes of different lipids, 3 of them having unsaturated components. 相似文献
75.
Mauro Tambasco Ian Nygren Eric Yorke-Slader J. Eduardo Villarreal-Barajas 《Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)》2013,29(5):537-544
The authors develop and investigate a user-friendly computational tool (FracMod) to quantify modulation complexity in planned IMRT fields.FracMod comprises a graphical user interface and variogram fractal dimension (FD) analysis tool developed by the authors using MATLAB®, and made freely available at http://www.medphysfiles.com/index.php. FracMod is investigated for its ability to identify overly-modulated dynamic IMRT fields designed for prostatic carcinoma treatments. A set of 5 prostate alone plans and 5 prostate plus pelvic node plans were used to choose FD cut-points that ensure no false positives in distinguishing between moderate and high field modulation. IMRT quality control (QC) was performed on all the treatment fields using Varian® Portal Dosimetry and MapCHECK?. Receiver operating characteristic analysis was used to quantitatively compare the classification performance of FD and the number of monitor units (MUs). The effect of dose rate on the average leaf pair opening (ALPO) and the number of MUs delivered was also investigated.The variogram FD performed better than the number of MUs in identifying overly-modulated fields.FD thresholds >2.15 for prostate alone and >2.20 for prostate plus pelvic nodes correctly identified 75% and 100% of the high modulation fields, respectively, with no false positives. With appropriate cut-points, MapCHECK? identified the most highly modulated IMRT fields, whereas Varian® Portal Dosimetry could not. As expected, ALPO decreases with increasing modulation and increasing dose rate.FracMod is a user-friendly tool that allows one to accurately quantify and identify overly-modulated IMRT fields at the treatment planning stage before they are sent for patient-specific QC. 相似文献
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Massimo Reverberi Mauro Picardo Alessandra Ricelli Emanuela Camera Corrado Fanelli Anna Adele Fabbri 《Free radical research》2013,47(6):833-841
In order to verify the role played by oxidation in the budding of potato tubers (Solanum tuberosum L. cv. Kennebec), the physiological events occurring below bud at 4°C have been studied for a period of 6 months. The low temperature storage induced an increase in the degree of unsaturation and a decrease in the ratio of saturated/unsaturated fatty acids of membrane polar lipids with a subsequent increase of lipid hydroperoxides (LOOH). Cold stress increased both enzymatic antioxidative activities (superoxide dismutase, SOD, E.C.1.15.1.1; catalase, CAT, E.C. 1.11.1.6), and α-tocopherol levels thus protecting membrane's polyunsaturated lipids. Between 0 and 15 days of storage SOD/CAT ratio, α-tocopherol, LOOH levels and the degree of lipid unsaturation showed strong variations. After 30 to 120/150 days the antioxidative system seemed to reach a homeostasis different from that of time 0, accompanied by a constant increase of indole-3-acetic acid (IAA) after 60 days. The antioxidative system, after 150 days, lost its efficiency while LOOH levels were maintained higher than time 0 and IAA concentration was sufficient to allow sprouting. 相似文献
78.
Massimo Reverberi Corrado Fanelli Slaven Zjalic Stefania Briganti Mauro Picardo Alessandra Ricelli 《Free radical research》2013,47(6):637-647
Plant responses to biotic and abiotic stress can be mediated by oxidised products and in this study we analysed the relation among some of them and the growth factor indole-3-acetic acid (IAA). The plant material used was potato tuber sliced below bud and incubated for different lengths of time before analysis. Wounding in potato tuber leads, in a very short time (0–30?min), to the generation of lipid hydroperoxides (LOOH) from polyunsaturated fatty acids (PUFA). These reactive species could cause a subsequent increase of 9 and 13-lipoxygenase (LOX, E.C.1.13.12.12.), analysed by RT-PCR and spectrophotometric assay, LOOH, Jasmonates and IAA all quantified by GC–MS analysis. The activation of 9 and 13-LOX, using different timing, leads to the formation of LOOH with a subsequent generation of jasmonates and IAA as highlighted by the addition on the potato tuber slices of salicylhydroxamic acid (SHAM), an inhibitor of LOX activity. A correlation between jasmonates and IAA resulted by testing their reciprocal influence during wounding in potato tuber. The relationship occurring among each hormone analysed during wounding underlines the fact that the jasmonates level can be regulated in situ and this can suggest a role for these compounds in potato tuber which has been underestimated up to now. 相似文献
79.
The genus Rimosodaphnella Cossmann, 1916 was proposed for Murex textile Brocchi, 1814, a European Miocene–Pliocene species, and is sometimes thought to be represented in the recent fauna by three Atlantic species. Here, we assign only one Atlantic species, Pleurotoma (Drillia) morra Dall, 1881 distributed from North Carolina to Southern Brazil, to the genus and introduce three new species of Rimosodaphnella from the Indo-Pacific region. One, Rimosodaphnella solomonensis, n. sp. from the Solomon Islands, while two others, Rimosodaphnella tenuipurpurata n. sp. and Rimosodaphnella brunneolineata n. sp., from the Philippines Islands; these findings suggest that the genus may be well represented in the Indo-Pacific region.http://zoobank.org/urn:lsid:zoobank.org:pubBD6E8AA4-445C-43A5-8171-65A7CE8BA20B 相似文献
80.
Laura Bonfili Massimiliano Cuccioloni Valentina Cecarini Matteo Mozzicafreddo Francesco Alessandro Palermo Paolo Cocci Mauro Angeletti Anna Maria Eleuteri 《Apoptosis : an international journal on programmed cell death》2013,18(10):1188-1200
Ghrelin is a metabolism-regulating hormone recently investigated for its role in cancer survival and progression. Controversially, ghrelin may act as either anti-apoptotic or pro-apoptotic factor in different cancer cells, suggesting that the effects are cell type dependent. Limited data are currently available on the effects exerted by ghrelin on intracellular proteolytic pathways in cancer. Both the lysosomal and the proteasomal systems are fundamental in cellular proliferation and apoptosis regulation. With the aim of exploring if the proteasome and autophagy may be possible targets of ghrelin in cancer, we exposed human colorectal adenocarcinoma cells to ghrelin. Preliminary in vitro fluorimetric assays evidenced for the first time a direct inhibition of 20S proteasomes by ghrelin, particularly evident for the trypsin-like activity. Moreover, 1 μM ghrelin induced apoptosis in colorectal adenocarcinoma cells by inhibiting the ubiquitin–proteasome system and by activating autophagy, with p53 having an “interactive” role. 相似文献