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71.
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
72.
73.
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
74.
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
75.
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
76.
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
77.
Mauro Paschetta Valentina La Morgia Dario Masante Matteo Negro Antonio Rolando Marco Isaia 《Journal of Insect Conservation》2013,17(2):339-356
Alpine pastures are typical examples of “high nature value farmlands”, representing important habitats harbouring unique biological communities. Disturbance induced by overgrazing influences significantly ecosystem processes, in which invertebrates play a major role. To develop new models of sustainable management of pastures, more knowledge is needed of the animal communities, essential to the ecological functioning of pasture ecosystems. The apparent poor ecological state of several pastures in the Natural Regional Park of Alpi Marittime (NW-Italy) lead us to evaluate the influence of grazing history on biodiversity, using spider and harvestmen assemblages as key groups. Four different pastoral types characterized by four different grazing histories were identified using the Daget-Poissonet method. Spiders and harvestmen were collected by means of pitfall traps. Arachnid assemblages were characterized in terms of composition, abundance, species richness, richness of endemic species and taxonomic relatedness. Generalized linear mixed models (GLMM) were used to test differences among assemblages occurring in each pastoral type. Furthermore, we tested differences in terms of plant communities (species richness and percentage of zoogenic species). Specificity and fidelity of every spider and harvestmen species within pastoral types were explored by the IndVal (Indicator Value) procedure. Fifty-eight species of spiders and seven species of harvestmen were collected (2,304 individuals). Pastoral types related to intensive grazing were characterized by the dominance of diurnal wanderer spiders (namely Lycosidae) while, conversely, nocturnal wanderers (mainly Gnaphosidae) were more abundant in extensive pastoral types. Results show that both species richness and spider abundance were higher in abandoned areas of extensive grazing, while endemic assemblages were richer in extensive grazed areas, which also hosted the most diverse plant community. Furthermore, most of the indicator species of spiders of this type were endemic, characterized by more demanding ecological requirements. 相似文献
78.
Cecilia Marini Barbara Salani Michela Massollo Adriana Amaro Alessia Isabella Esposito Anna Maria Orengo Selene Capitanio Laura Emionite Mattia Riondato Gianluca Bottoni Cinzia Massara Simona Boccardo Marina Fabbi Cristina Campi Silvia Ravera Giovanna Angelini Silvia Morbelli Michele Cilli Renzo Cordera Mauro Truini Davide Maggi Ulrich Pfeffer Gianmario Sambuceti 《Cell cycle (Georgetown, Tex.)》2013,12(22):3490-3499
Emerging evidence suggests that metformin, a widely used anti-diabetic drug, may be useful in the prevention and treatment of different cancers. In the present study, we demonstrate that metformin directly inhibits the enzymatic function of hexokinase (HK) I and II in a cell line of triple-negative breast cancer (MDA-MB-231). The inhibition is selective for these isoforms, as documented by experiments with purified HK I and II as well as with cell lysates. Measurements of 18F-fluoro-deoxyglycose uptake document that it is dose- and time-dependent and powerful enough to virtually abolish glucose consumption despite unchanged availability of membrane glucose transporters. The profound energetic imbalance activates phosphorylation and is subsequently followed by cell death. More importantly, the “in vivo” relevance of this effect is confirmed by studies of orthotopic xenografts of MDA-MB-231 cells in athymic (nu/nu) mice. Administration of high drug doses after tumor development caused an evident tumor necrosis in a time as short as 48 h. On the other hand, 1 mo metformin treatment markedly reduced cancer glucose consumption and growth. Taken together, our results strongly suggest that HK inhibition contributes to metformin therapeutic and preventive potential in breast cancer. 相似文献
79.
Anna Licata Salvatore Corrao Salvatore Petta Chiara Genco Mauro Cardillo Vincenza Calvaruso Giuseppe Cabibbo Fatima Massenti Calogero Cammà Giuseppe Licata Antonio Craxì 《PloS one》2013,8(8)
Background and Aims
Plasma levels of NT-pro-BNP, a natriuretic peptide precursor, are raised in the presence of fluid retention of cardiac origin and can be used as markers of cardiac dysfunction. Recent studies showed high levels of NT pro BNP in patients with cirrhosis. We assessed NT pro-BNP and other parameters of cardiac dysfunction in patients with cirrhosis, with or without ascites, in order to determine whether the behaviour of NT pro BNP is linked to the stage of liver disease or to secondary cardiac dysfunction.Methods
Fifty eight consecutive hospitalized patients mostly with viral or NAFLD-related cirrhosis were studied. All underwent abdominal ultrasound and upper GI endoscopy. Cardiac morpho-functional changes were evaluated by echocardiography and NT-pro-BNP plasma levels determined upon admission. Twenty-eight hypertensive patients, without evidence of liver disease served as controls.Results
Fifty eight cirrhotic patients (72% men) with a median age of 62 years (11% with mild arterial hypertension and 31% with type 2 diabetes) had a normal renal function (mean creatinine 0.9 mg/dl, range 0.7–1.06). As compared to controls, cirrhotic patients had higher NT pro-BNP plasma levels (365.2±365.2 vs 70.8±70.6 pg/ml; p<0.001). Left atrial volume (LAV) (61.8±26.3 vs 43.5±14.1 ml; p = 0.001), and left ventricular ejection fraction (62.7±6.9 vs. 65.5±4%,; p = 0.05) were also altered in cirrhotic patients that in controls. Patients with F2-F3 oesophageal varices as compared to F0/F1, showed higher e'' velocity (0.91±0.23 vs 0.66±0.19 m/s, p<0.001), and accordingly a higher E/A ratio (1.21±0.46 vs 0.89±0.33 m/s., p = 0.006).Conclusion
NT-pro-BNP plasma levels are increased proportionally to the stage of chronic liver disease. Advanced cirrhosis and high NT-pro-BNP levels are significantly associated to increased LAV and to signs of cardiac diastolic dysfunction. NT pro-BNP levels could hence be an useful prognostic indicators of early decompensation of cirrhosis. 相似文献80.
Caio Cesar de Souza Alves Adam Collison Luke Hatchwell Maximilian Plank Matthew Morten Paul S. Foster Sebastian L. Johnston Cristiane Fran?a da Costa Mauro Vieira de Almeida Henrique Couto Teixeira Ana Paula Ferreira Joerg Mattes 《PloS one》2013,8(11)