1,721,241 research outputs found
In vitro and in vivo antitumoral effects of polyphenols or combination of polyphenols in head and neck cancer and in malignant mesothelioma
No full textCarcinogenesis is a multistep process triggered by genetic alterations that activate different signal transduction pathways and cause the progressive transformation of a normal cell into a cancer cell. Polyphenols, such as Curcumin and Resveratrol, have the ability to modulate the activity of multiple targets involved in carcinogenesis and can be employed to inhibit the growth of cancer cells. The aim of this study was to demonstrate the in vitro and in vivo antitumoral effects of Curcumin, in the treatment of epithelial (head and neck cancer “HNC”) and mesenchimal (malignant mesothelioma “MM”) tumors, used as single compound or in combination with Resveratrol. In the 1° report we provide evidence that the combination of Resveratrol (RES) and Curcumin (CUR) enhanced CUR in vitro and in vivo antitumor activities on HNC cell lines compared to the single compound; RES potentiates the apoptotic effect and reduced the IC50 of CUR on HNC cell lines. The model of compounds interaction indicated the onset of an additive effect of the two compounds compared to the single treatment after decrease of their concentrations. RES+CUR compared to CUR increased the PARP-1 cleavage, the Bax/Bcl-2 ratio, the inhibition of ERK1 and ERK2 phosphorylation, and the expression of LC3 II simultaneously with the formation of autophagic vacuoles. RES and CUR induced cytoplasmic NF-kB accumulation. Moreover, RES+CUR in vivo administrations were safe in BALB/c mice and reduced the growth of transplanted salivary gland cancer cells (SALTO) more efficiently than CUR. In the 2° report we demonstrate the in vitro antitumoral activities of CUR on MM cell lines; CUR in vitro inhibited MM cells survival in a dose- and time-dependent manner, increased reactive oxygen species intracellular production and induced DNA damage. CUR triggered autophagic flux, but the process was then blocked and was coincident with caspase 8 activation which activates apoptosis. Moreover, CUR treatment stimulated the phosphorylation of ERK1/2 and p38 MAPK, inhibited that of p54 JNK and AKT and prevented NF-κB nuclear translocation. These findings may have important implications for the design of HNC and MM treatment using CUR as single compound or in combination with Resveratrol
Effetti della nutrizione precoce su crescita e neurosviluppo
No full textIntroduzione: Durante la vita fetale la madre fornisce attraverso la placenta elevate concentrazioni di calorie e proteine. Per nutrizione “aggressiva” si intende la somministrazione, tramite nutrizione parenterale, di apporti calorico-proteici simili a quelli ricevuti in utero, sin dai primi minuti di vita extrauterina.
Obiettivi: Valutare sicurezza ed efficacia della nutrizione parenterale “aggressiva” da parte del neonato pretermine.
Metodi: Studio osservazionale con raccolta dati di tipo prospetto ed analisi retrospettiva su neonati con peso alla nascita inferiore a 1500 grammi o età gestazionale inferiore a 31 settimane osservati presso l’Unità di Terapia Intensiva Neonatale dell’Università di Roma “Sapienza”. Sono state confrontate 2 tipologie di nutrizione “aggressiva” arruolando i neonati in 2 gruppi. Il gruppo 1 ha ricevuto un apporto proteico di 2 g/Kg/die in prima giornata con aumenti quotidiani di circa 1g/Kg fino a 4 g/Kg/die di proteine, ed un rapporto Kcal/proteine pari a circa 25 Kcal per ogni grammo di proteine. Il Gruppo 2 ha ricevuto un apporto proteico simile ma con un rapporto Kcal/proteine pari a circa 30 Kcal per ogni grammo di proteine. Sono stati raccolti prospetticamente dati riguardo la sicurezza (i.e. disturbi metabolismo glucidico, lipidico e alterazioni elettrolitiche) e l’efficacia (crescita extrauterina, sviluppo neuromotorio a 12 mesi di età corretta per l’età gestazionale) delle due differenti strategie nutrizionali.
Risultati: I due gruppi sono risultati simili riguardo le principali caratteristiche demografiche e cliniche (peso nascita, 1112±243 vs 1101±259 grammi; età gestazionale, 29.1±2.3 vs 30.0±2.7 settimane, sesso maschile 53% vs 63%) e l’incidenza di morbidità (39.8 vs 36.2 p=0.675). I neonati arruolati nel Gruppo 1 (7.1%) hanno mostrato una minore incidenza di iperglicemia severa (glu >216 mg/dl) rispetto a quelli del Gruppo 2 (19.1%; p=0.031). Una maggiore incidenza di acidosi metabolica è stata riscontrata invece nei soggetti del Gruppo 1 rispetto a quelli del Gruppo 2 (74.5% vs 48.6%; p=0.005). Il peso alla dimissione è risultato maggiore nel Gruppo 2 (2580±654 grammi) rispetto al Gruppo 1 (2463±448 grammi, p=0.010). Non sono state evidenziate differenze relative al livello di sviluppo neuromotorio in relazione ai differenti approcci nutrizionali.
Conclusioni: Un aumentato apporto calorico-proteico nella prima settimana di vita migliora la crescita extrauterina del neonato pretermine, aumenta il rischio di iperglicemia e non mostra effetti sul neuro sviluppo valutato a 12 mesi di età corretta. I risultati di questo studio pongono le basi per la definizione degli apporti calorico-proteici ideali per il neonato pretermine
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Omnis definitio in iure... La responsabilità medica e la problematica distinzione tra i tipi di colpa generica
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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