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Institution

University of Naples Federico II

EducationNaples, Campania, Italy
About: University of Naples Federico II is a education organization based out in Naples, Campania, Italy. It is known for research contribution in the topics: Population & Cancer. The organization has 29291 authors who have published 68803 publications receiving 1920149 citations. The organization is also known as: Università degli Studi di Napoli Federico II & Naples University.


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Journal Article
TL;DR: The present study shows that macrolide antibiotics have anti-inflammatory activity, which likely depends on their ability to prevent the production of proinflammatory mediators and cytokines, and suggests that these agents, particularly roxithromycin, can exert therapeutic effects independently of their antibacterial activity.
Abstract: The effect of four macrolide antibiotics (roxithromycin, clarithromycin, erythromycin, and azithromycin) on the generation of some mediators and cytokines involved in the inflammatory process has been studied both in vivo and in vitro. Rat carrageenin pleurisy was used as a model of acute inflammation, and the macrolides were administered (10, 20, and 40 mg/kg p.o.) 1 h before the carrageenin challenge. Exudate volume and leukocyte accumulation were both dose-dependently reduced by roxithromycin, clarithromycin and erythromycin in either normal or adrenalectomized animals. Furthermore, in normal rats, prostaglandin (PG)E(2), nitrate plus nitrite, and tumor necrosis factor-alpha levels in pleural exudate were significantly reduced by these macrolides. Roxithromycin appeared more effective than erythromycin and clarithromycin, whereas azithromycin only slightly affected the inflammatory reaction. None of the macrolides were able to modify leukotriene B(4) exudate levels. In vitro experiments have shown that the four macrolides (5-80 microM) reduced in a concentration-dependent manner the production of 6-keto-PGF(1alpha), NO(2)(-), tumor necrosis factor-alpha, interleukin-1beta, and interleukin-6 by lipopolysaccharide-stimulated J774 macrophages. In J774 cells, the inhibition of 6-keto-PGF(1alpha) and NO(2)(-) production by roxithromycin and erythromycin was not dependent on direct inhibition of cyclooxygenase-2 and inducible nitric oxide synthase activity because it appears to be related to the inhibition of cyclooxygenase-2 and inducible nitric oxide synthase protein expression. In conclusion, the present study shows that macrolide antibiotics have anti-inflammatory activity, which likely depends on their ability to prevent the production of proinflammatory mediators and cytokines, and suggest that these agents, particularly roxithromycin, can exert therapeutic effects independently of their antibacterial activity.

411 citations

Journal ArticleDOI
TL;DR: A very small inverse association between intake of total fruits and vegetables and cancer risk was observed in this study, and caution should be applied in their interpretation.
Abstract: BACKGROUND: It is widely believed that cancer can be prevented by high intake of fruits and vegetables. However, inconsistent results from many studies have not been able to conclusively establish an inverse association between fruit and vegetable intake and overall cancer risk. METHODS: We conducted a prospective analysis of the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort to assess relationships between intake of total fruits, total vegetables, and total fruits and vegetables combined and cancer risk during 1992-2000. Detailed information on the dietary habit and lifestyle variables of the cohort was obtained. Cancer incidence and mortality data were ascertained, and hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox regression models. Analyses were also conducted for cancers associated with tobacco and alcohol after stratification for tobacco smoking and alcohol drinking. RESULTS: Of the initial 142 605 men and 335 873 women included in the study, 9604 men and 21 000 women were identified with cancer after a median follow-up of 8.7 years. The crude cancer incidence rates were 7.9 per 1000 person-years in men and 7.1 per 1000 person-years in women. Associations between reduced cancer risk and increased intake of total fruits and vegetables combined and total vegetables for the entire cohort were similar (200 g/d increased intake of fruits and vegetables combined, HR = 0.97, 95% CI = 0.96 to 0.99; 100 g/d increased intake of total vegetables, HR = 0.98, 95% CI = 0.97 to 0.99); intake of fruits showed a weaker inverse association (100 g/d increased intake of total fruits, HR = 0.99, 95% CI = 0.98 to 1.00). The reduced risk of cancer associated with high vegetable intake was restricted to women (HR = 0.98, 95% CI = 0.97 to 0.99). Stratification by alcohol intake suggested a stronger reduction in risk in heavy drinkers and was confined to cancers caused by smoking and alcohol. CONCLUSIONS: A very small inverse association between intake of total fruits and vegetables and cancer risk was observed in this study. Given the small magnitude of the observed associations, caution should be applied in their interpretation.

411 citations

Journal ArticleDOI
TL;DR: In this paper, the authors quantify the ultimate tensile strength and nominal strain at break of printed parts made from polylactic acid (PLA) with a Replicating Rapid prototyper (Rep-Rap) 3D printer, by varying three important process parameters: layer thickness, infill orientation and the number of shell perimeters.
Abstract: Purpose – This study aims to quantify the ultimate tensile strength and the nominal strain at break (ɛf) of printed parts made from polylactic acid (PLA) with a Replicating Rapid prototyper (Rep-Rap) 3D printer, by varying three important process parameters: layer thickness, infill orientation and the number of shell perimeters. Little information is currently available about mechanical properties of parts printed using open-source, low-cost 3D printers. Design/methodology/approach – A computer-aided design model of a tensile test specimen was created, conforming to the ASTM:D638. Experiments were designed, based on a central composite design. A set of 60 specimens, obtained from combinations of selected parameters, was printed on a Rep-Rap Prusa I3 in PLA. Testing was performed using a JJ Instruments – T5002-type tensile testing machine and the load was measured using a load cell of 1,100 N. Findings – This study investigated the main impact of each process parameter on mechanical properties and the effe...

410 citations

Journal ArticleDOI
TL;DR: The current state-of-the art suggests a complex relationship between cancer and deregulated autophagy that must be disentangled by further in-depth investigation.
Abstract: Multiple oncogenes (in particular phosphatidylinositol 3-kinase, PI3K; activated Akt1; antiapoptotic proteins from the Bcl-2 family) inhibit autophagy. Similarly, several tumor suppressor proteins (such as BH3-only proteins; death-associated protein kinase-1, DAPK1; the phosphatase that antagonizes PI3K, PTEN; tuberous sclerosic complex 1 and 2, TSC1 and TSC2; as well as LKB1/STK11) induce autophagy, meaning that their loss reduces autophagy. Beclin-1, which is required for autophagy induction acts as a haploinsufficient tumor suppressor protein, and other essential autophagy mediators (such as Atg4c, UVRAG and Bif-1) are bona fide oncosuppressors. One of the central tumor suppressor proteins, p53 exerts an ambiguous function in the regulation of autophagy. Within the nucleus, p53 can act as an autophagy-inducing transcription factor. Within the cytoplasm, p53 exerts a tonic autophagy-inhibitory function, and its degradation is actually required for the induction of autophagy. The role of autophagy in oncogenesis and anticancer therapy is contradictory. Chronic suppression of autophagy may stimulate oncogenesis. However, once a tumor is formed, autophagy inhibition may be a therapeutic goal for radiosensitization and chemosensitization. Altogether, the current state-of-the art suggests a complex relationship between cancer and deregulated autophagy that must be disentangled by further in-depth investigation.

410 citations

Journal ArticleDOI
TL;DR: In this article, an adaptive perturb and observe (P&O) method is proposed to track the maximum power point (MPPT) in photovoltaic (PV) systems.
Abstract: The optimisation of energy generation in a photovoltaic (PV) system is necessary to let the PV cells operate at the maximum power point (MPP) corresponding to the maximum efficiency. Since the MPP varies, based on the irradiation and cell temperature, appropriate algorithms must be utilised to track the MPP. This is known as maximum power point tracking (MPPT). Different MPPT algorithms, each with its own specific performance, have been proposed in the literature. A so-called perturb and observe (P&O) method is considered here. This method is widely diffused because of its low-cost and ease of implementation. When atmospheric conditions are constant or change slowly, the P&O method oscillates close to MPP. However, when these change rapidly, this method fails to track MPP and gives rise to a waste of part of the available energy. An adaptive P&O method is proposed in this study that has faster dynamics and improved stability compared to the traditional P&O. The MPPT algorithm was set up and validated by means of numerical simulations and experimental tests, confirming the effectiveness of the method.

409 citations


Authors

Showing all 29740 results

NameH-indexPapersCitations
D. M. Strom1763167194314
Yang Gao1682047146301
Robert Stone1601756167901
Elio Riboli1581136110499
Barry J. Maron15579291595
H. Eugene Stanley1541190122321
Paul Elliott153773103839
Robert O. Bonow149808114836
Kai Simons14742693178
Peter Buchholz143118192101
Martino Margoni1412059107829
H. A. Neal1411903115480
Luca Lista1402044110645
Pierluigi Paolucci1381965105050
Ari Helenius13729864789
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
2023234
2022660
20216,021
20205,957
20194,881
20184,267