38,551 research outputs found
Influential parameters on particle concentration and size distribution in the mainstream of e-cigarettes
No full textElectronic cigarette-generated mainstream aerosols were characterized in terms of particle number concentrations and size distributions through a Condensation Particle Counter and a Fast Mobility Particle Sizer spectrometer, respectively. A thermodilution system was also used to properly sample and dilute the mainstream aerosol.\ud
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Different types of electronic cigarettes, liquid flavors, liquid nicotine contents, as well as different puffing times were tested. Conventional tobacco cigarettes were also investigated.\ud
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The total particle number concentration peak (for 2-s puff), averaged across the different electronic cigarette types and liquids, was measured equal to 4.39 ± 0.42 × 109 part. cm−3, then comparable to the conventional cigarette one (3.14 ± 0.61 × 109 part. cm−3). Puffing times and nicotine contents were found to influence the particle concentration, whereas no significant differences were recognized in terms of flavors and types of cigarettes used.\ud
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Particle number distribution modes of the electronic cigarette-generated aerosol were in the 120–165 nm range, then similar to the conventional cigarette one
IL FUOCO ATTENTIVO: ALCUNE QUESTIONI IRRISOLTE
No full textIn questo lavoro si indaga su alcune questioni ancora irrisolte sul fuoco attentivo:
i margini del fuoco sono definiti e differenziati dalle zone circostanti non interessate
dall’attenzione? Le differenze nella prestazione in un compito di detezione sono
spiegabili efficacemente con l’ipotesi del dimensionamento del fuoco attentivo in base
alle richieste del compito? Le differenze nella prestazione sono di natura attentiva e
non attribuibili a effetti retinici? I risultati depongono a favore di una risposta affermativa
per tutte le domande sopra esposte
Apoptosome structure and regulation
No full textThe apoptosome is a multimolecular complex assembled around the adaptor protein Apaf I upon mitochondria-mediated apoptosis. The formation of the apoptosome needs the presence of ATP/dATP and cytochrome c in the cytosol and triggers the activation of caspases which - in turn - drive cell demise. Apoptosis plays a key role in the homeostasis of all multicellular organisms and, indeed, with regard to its essential components the apoptosome is evolutionary conserved. However, higher eukaryotes, according to their complexity, have evolved more complicated and finely tuned mechanisms for controlling apoptosome activity. Since apoptosome dysfunctions can cause many human diseases, this complex is also a relevant molecular target in biomedicine and the understanding of its structure and its regulation is matter of great interest for scientists
Apotosome: structure and regulation
No full textThe apoptosome is a multimolecular complex assembled around the adaptor protein Apaf1 upon mitochondria-mediated apoptosis. The formation of the apoptosome needs the presence of ATP/dATP and cytochrome c in the cytosol and triggers the activation of caspases which - in turn - drive cell demise. Apoptosis plays a key role in the homeostasis of all multicellular organisms and, indeed, with regard to its essential components the apoptosome is evolutionary conserved. However, higher eukaryotes, according to their complexity, have evolved more complicated and finely tuned mechanisms for controlling apoptosome activity. Since apoptosome dysfunctions can cause many human diseases, this complex is also a relevant molecular target in biomedicine and the understanding of its structure and its regulation is matter of great interest for scientists
Le armi, il fuoco : la sconfitta di Prometeo
No full textIl fuoco, uno dei quattro principi di vita secondo la scuola filosofica greca, è diventato nel tempo principio di sterminio. La storia sempre più si affolla di momenti in cui il fuoco si fa negatore di vita e di libertà. L'idea della conquista e l'idea della distruzione si confrontano senza fine. Davanti alla corsa parallela dell'ingiustizia e della violenza l'acqua si afferma come superiore principio di vita. Le armi e i loro dilagare, attraverso le guerre o attraverso le imprese della criminalità organizzata, segnano invece la sconfitta della illusione di Prometeo, quella di portare con la sua fiaccola la libertà agli uomini assoggettati agli dei
A New Method for Characterization of Natural Zeolites and Organic Nanostructure using Atomic Force Microscopy
No full textIn order to study and develop an economic solution to environmental pollution in water, a wide variety of materials were investigated. Natural zeolites emerge from that research as the best in class of this category. Zeolites are natural materials relatively abundant and non biodegradable, economic and good to perform processes of environmental remediation. This paper contains a full description of a new method to characterize superficial properties of natural zeolites of exotic provenience (Caribbean Islets) with atomic force microscopy (AFM). AFM works with the optical microscope simplicity and the high resolution typical of a transmission electron microscope (TEM). Structural information of mesoporous material is obtained using scanning and transmission electron microscopy (SEM and TEM), only if the sample is conductive, otherwise the sample has to be processed through the grafitation technique, but this procedure induces errors of topography. Therefore, the existing AFM method, to observe zeolite powders, is made in a liquid cell-head scanner, but this work puts in evidence and confirms that it is possible to use an ambient air-head scanner to obtain a new kind of microtopography. Once optimized, this new method allows investigating of organic micelles, very soft nanostructure, of cetyltriammonium bromide (CTAB) upon an inorganic surface such as natural zeolites. It is shown some correlation between SEM microphotographies and AFM 3D images
Analysis of apoptosome dysregulation in pancreatic cancer and of its role in chemoresistance
No full textThe apoptosome is a multiprotein complex mediating the mithochondrial pathway of cell death. Its importance during development has been clearly demonstrated by knocking out key genes in mouse. APAF1 is the core protein of the apoptosome and its dosage is also critical in various cancer types, i.e., melanoma, germ line tumor, gastrointestinal cancer and B - type chronic lymphocytic leukemia. This is generally due to inactivation of the APAF1 locus by epigenetic phenomena or by activity of promoter regulators. We investigated the putative roles of the apoptosome in pancreatic ductal adenocarcinoma (PDAC). We found that both APAF1 mRNA and protein are dysregulated in human PDAC samples. Similarly, several PDAC cell lines exhibited variable levels of both APAF1 protein and mRNA. The response to cell death induction and its biochemical features were assessed by treatment of each line with commonly used chemotherapeutic agents. We found that the apoptosome pathway was not functional in most cell lines upon cytochrome c release from mitochondria. In addition, we restored APAF1 and Caspase - 9 dosage in Panc - 1 cells, where the apoptosome is downregulated, by overexpressing the murine cDNA of the two molecules, and we improved the death response to chemotherapeutic agents
Erratum to: Effect of moderate red wine intake on cardiac prognosis after recent acute myocardial infarction of subjects with Type 2 diabetes mellitus (Diabetic Medicine, (2006), 23, 9, (974-981), 10.1111/j.1464-5491.2006.01886.x)
No full textIn an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola.In an article by Marfella et al, the author name C. Saron is incorrect and should be listed as C. Sardu. Therefore the correct author list is: R. Marfella, F. Cacciapuoti, M. Siniscalchi, F. C. Sasso, F. Marchese, F. Cinone, E. Musacchio, M. A. Marfella, L. Ruggiero, G. Chiorazzo, D. Liberti, G. Chiorazzo, G. F. Nicoletti, C. Sardu, F. D'Andrea, C. Ammendola, M. Verza and L. Coppola
L’applicazione del metodo di Dahl sulle lesioni cutanee da arma da fuoco per lo studio della distanza di sparo.
No full textLa dimostrazione della presenza dei residui dell'innesco (Pb, Sb, Ba, Zn, Ti) sulla cute attinta da un colpo d'arma da fuoco, indica che il colpo è stato sparato da breve distanza. Nel presente lavoro gli Autori hanno applicato il metodo di Dahl che sfrutta la capacità dell'Alizarina Red S (ARS) di produrre precipitati di colore rosso rubino con il bario, su 105 lesioni cutanee da arma da fuoco con distanza dello sparo da 0 cm a più di un metro. I risultati ottenuti hanno dimostrato sia la specificità di questa tecnica, in quanto solo i colpi a contatto ed a breve distanza hanno reagito positivamente, sia la sua sensibilità, in quanto la reazione si è verificata anche in corrispondenza di isolati residui di innesco frammisti a singoli precipitati della carica di lancio
Uric acid is associated with inflammatory biomarkers and induces inflammation via activating the NF-κB signaling pathway in HepG2 cells
No full textObjective-Serum uric acid (UA) has been associated with increased risk of cardiovascular and metabolic diseases. However, the causal mechanisms linking elevated UA levels to cardio-metabolic diseases are still unsettled. One potential explanation for how UA might contribute to cardio-metabolic disease might be its ability to induce systemic inflammation. Approach and Results-Herein, we report a positive relationship between serum UA and acute-phase reactants, such as high-sensitivity C-reactive protein, fibrinogen, ferritin, complement C3, and erythrocyte sedimentation rate, in a cohort of 2731 nondiabetic adults. The relationship remains significant after adjustment for several confounders, including age, sex, adiposity, anti-hypertensive treatments or diuretics use. To confirm the existence of a causal relationship, we examined the effect of UA on the expression of inflammatory biomarkers in human hepatoma HepG2 cells and characterized the signaling pathway by which UA acts. We show that UA stimulates the expression of C-reactive protein, fibrinogen, ferritin, and complement C3 in a dose-dependent fashion. The proinflammatory effects of UA were abrogated by benzbromarone, a specific inhibitor of UA transporters. Exposure of cells to UA resulted in activation of the IκB kinase/IκBα/NF-κB signaling pathway that was attenuated by benzbromarone. The effect of UA was completely blocked by the antioxidant N-acetylcysteine. Conclusions-These in vivo and in vitro data suggest that hyperuricemia might induce the expression of hepatic inflammatory molecules by activating the proinflammatory NF-κB signaling cascade. Because inflammation has an important pathogenetic role in metabolic and cardiovascular disease, our study may help understanding the mechanism by which hyperuricemia may contribute to organ damage
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