Chronic treatment with statins increases the availability of selenium in the antioxidant defence systems of hemodialysis patients.

Project. Oxidative stress (OS) is enhanced in hemodialysis (HD) patients. Lipid peroxidation and oxidative damage to glycids, proteins and nucleic acids are main consequences of OS and are associated to increased cardiovascular risk. Vitamin E and Glutathione Peroxidase (GSH-Px) represent main antioxidant systems in human cells. Selenium (Se), bound to the active sites of GSH-Px, plays a critical role in this antioxidant defense system. Statins are widely used and extensively investigated in the prevention of cardiovascular disease, notably in high-risk subjects. Several studies suggest that statins show antioxidant effects, protecting low-density lipoproteins from oxidation. Aim of our study was to compare serum Se concentration in ESRD patients on maintenance HD and in homogeneous healthy subjects and to investigate whether chronic assumption of statins may interfere with serum Se concentration in HD patients. Procedure. A total of 103 HD patients and 69 healthy subjects were enrolled; HD patients were then divided into patients who were not treated with statins (group A) and patients who assumed statins since six months at least (group B). Serum Se was determined by atomic absorption spectrometry. Results. Serum Se was significantly lower in HD patients of group A compared to healthy subjects (81.65±19.66mcg/L Vs. 96.47±15.62mcg/L, p<0.0040). However, in HD patients who assumed statins serum Se was significantly higher than in HD patients who did not. (111.83±18.82mcg/L Vs. 81.65±19.66mcg/L, p<0.0001). Conclusions. our results suggest that in HD patients chronic assumption of statins is related to a higher availability of active antioxidant agents and to reduced oxidative stress

Approaches, Strategies and Theoretical and Practice-Based Research Methods to investigate and archive video art:Some reflections from the REWIND projects

This paper will discuss methodologies, approaches and issues, emerging out of three major research projects that have investigated early histories of video art in Europe: REWIND (2004 ongoing), REWINDItalia (2011-2014) and EWVA (2015-2018). The paper will discuss how the projects have engaged with the history of the apparatus, the identity and status of the artworks, preservation methods, and the legacy of these video artworks today. A particular focus will be on semi-structured questionnaires for interviews structured to capture oral histories, memories and recollections, that in some cases would have been otherwise lost to future knowledge and the uncovering of lost artworks and their available documentation. The speakers directly involved in the projects - will discuss solutions, risks and experiences encountered in the projects and future research perspectives for re-covering, collecting, archiving and narrating the histories of early video art in Europe. The paper will discuss also different practice-based research methods, platforms and engagement strategies, including re-installation and re-enactment

Behavioural plasticity in Argyrodes antipodiana.

In this thesis I look at the behavioural plasticity of A.antipodiana while foraging and interacting with conspecifics. The aim is to see how an animal, with apparently limited intelligence is able to deal with environmental variability. I conclude that A.antipodiana appears to have been able to overcome these limitations very effectively by using four methods, of which the first two effectively reduce the amount of learning necessary. Firstly, A.antipodiana simplifies the situation as much as possible by ignoring some of the variability. For example, in social situations, A.antipodiana appears to recognize only a few categories of conspecifics, rather than recognize conspecifics as individuals. Consequently, the social groups of A.antipodiana are not characterized by complicating factors such as aggressive orders or dominance hierarchies. Secondly, A.antipodiana largely ignores current situations and instead bases much of its behavioural decisions on its internal conditions. For example, in male-male conflicts, males respond to their opponents largely according to their own size, level of hunger, the number of contests in which they have participated, or their past experience of winning or losing; rather than to the characteristics of their opponents. Likewise in social interactions A.antipodiana is more inclined to be aggressive towards conspecifics if it itself is foraging, and less inclined if it is feeding with the host. When the situation cannot be simplified, A.antipodiana adopts a third response which is to use the simplest method possible for adjusting its behaviour. For example, A.antipodiana's ability to develop araneophagic skills appears to be governed by a critical period. Thus rather than developing araneophagic skills through trial and error with practise, the ability appears to be simply 'switched on' if required. The fourth means by which A.antipodiana compensates for limited intelligence is to be very selective in the areas in which it does use learning. For example, A.antipodiana seems to use problem solving when foraging, but only when it is actually trying to reach the food bundle upon which the host is feeding. A.antipodiana also seems to learn to move more stealthfully on the host's web. There is even evidence that A.antipodiana may behave with intent when males are competing for opportunities to copulate. Thus the intelligence of A.antipodiana appears to be severely limited. However, despite these limitations, by reducing the amount of learning necessary, and then channelling what learning it has to very restricted, but very poignant areas of its behaviour, A.antipodiana, is able to respond very effectively to its variable environment

Robust and prototypical immune responses toward COVID-19 vaccine in First Nations peoples are impacted by comorbidities

High-risk groups, including Indigenous people, are at risk of severe COVID-19. Here we found that Australian First Nations peoples elicit effective immune responses to COVID-19 BNT162b2 vaccination, including neutralizing antibodies, receptor-binding domain (RBD) antibodies, SARS-CoV-2 spike-specific B cells, and CD4+ and CD8+ T cells. In First Nations participants, RBD IgG antibody titers were correlated with body mass index and negatively correlated with age. Reduced RBD antibodies, spike-specific B cells and follicular helper T cells were found in vaccinated participants with chronic conditions (diabetes, renal disease) and were strongly associated with altered glycosylation of IgG and increased interleukin-18 levels in the plasma. These immune perturbations were also found in non-Indigenous people with comorbidities, indicating that they were related to comorbidities rather than ethnicity. However, our study is of a great importance to First Nations peoples who have disproportionate rates of chronic comorbidities and provides evidence of robust immune responses after COVID-19 vaccination in Indigenous people

TEST DINAMICI E MODELLI COSTITUTIVI DI GOMME NBR

Il lavoro ha lo scopo di studiare il comportamento a compressione di gomme NBR in test dinamici effettuati con una barra di Hopkinson in PET. Per tener conto del mezzo viscoelastico, le onde sperimentali sono state traslate e sono state applicate le formule corrette per barre in materiale polimerico. Nei test si è manifestato il fenomeno di barelling. I valori di strain logaritmici raggiunti ricadono nell’intervallo 0.7-1.0; i valori ingegneristici dello strain-rate nell’intervallo 150-700 s-1. E’ stato evidenziato che la legge costitutiva del materiale è molto sensibile allo strain rate; infatti le curve stress-strain sperimentali sono state utilizzate per la calibrazione di un modello costitutivo iperelasticoperfettamente viscoelastico: modelli di Mooney-Rivlin sono stati adottati per l’iperelasticità; la serie di Prony per la viscoelasticità. Il fitting tra le curve sperimentali e numeriche ha consentito di ricavare il modulo complesso delle gomme NBR in funzione della frequenza

Renin-angiotensin-aldosterone system in primary hyperparathyroidism before and after surgery

Twenty consecutive unselected patients with proven primary hyperparathyroidism (PH), 26 essential hypertensive (EH) patients, and 13 normotensives were studied. Blood pressure (BP) and, under constant salt intake, plasma renin activity (PRA), parathyroid hormone (PTH), urinary and plasma sodium, potassium, aldosterone (ALD), creatinine, total calcium, and phosphate were measured. Patients with PH were also studied 1 and 6 months after successful surgery. In patients with PH, systolic and diastolic BP was significantly lower (P < .001) than in EH patients and higher (P < .005) than in controls. Eight patients with PH (40%) had BP levels greater than 140/90 mm Hg. PTH and plasma and urinary calcium in patients with PH were significantly (P < .01) higher than in controls, while PRA, ALD, phosphate, potassium, and sodium were superimposable in the three groups. PTH in patients with PH was weakly correlated with PRA (positively) and with plasma potassium (negatively) and was not associated with ALD, calcium, sodium, and BP levels. Surgery was followed by a significant reduction (P < .01) in PTH, calcium, and urinary phosphate and an increase (P < .02) in plasma phosphate, potassium, and sodium, whereas PRA, ALD, urinary potassium and sodium, and BP showed no change. In hypertensive patients with PH, PTH, PRA, and plasma and urinary ALD, calcium, and sodium did not differ from the values in normotensive PH patients, and variations in these humoral parameters after surgery were comparable in the two groups. In conclusion, our results show that hypertension is frequently associated with PH. However, the present data raise doubts about the assumption of a renin-mediated causal relationship between hyperparathyroidism and high BP. Indeed, as a unique finding in favor of the hypothesis of a stimulating role of PTH in renin secretion, we observed only a weak relation between PTH and PRA. Thus, unknown and/or unassessed factors related to parathyroid disease cannot be ruled out to explain the hypertension observed in some patients with PH

Cardiovascular outcome in asymptomatic hemodialysis patients submitted to aggressive medical therapy: results of a four-year follow-up

Cardiovascular disease is a leading cause of morbidity and mortality in end-stage renal disease (ESRD) patients on maintenance hemodialysis (HD). Neither traditional nor emerging risk factors for cardiovascular disease can explain completely this excess of morbidity and mortality and the role and timing of primary prevention strategies in this population has not been clarified. The aim of this study was to assess if an aggressive pharmacological preventive treatment may reduce the myocardial ischemic burden and then improve the cardiovascular outcome In ESRD patients