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Green composites made of biodegradable matrices and lignocellulosic fibers are receiving growing attention from both academia and industries. Despite a wide literature can be found about mechanical behavior of such kind of composites, at the best of our knowledge, only limited information is available about their creep behavior [1] and no papers have been yet done on the effect of ultraviolet exposition. The tensile creep behavior at 40 °C of PLA based composites, containing flax and jute twill weave woven fabrics, produced through compression molding, was investigated. As preliminary characterization, quasi-static tensile tests were carried out on virgin and UV aged composites

Over the last decades, polymer composites containing natural fibers are receiving growing attention both from academia and the industry, as possible alternatives of composites containing synthetic fibers [1]. Moreover, in order to reduce the environmental impacts related to the use of oil-derived polymer matrices, biodegradable ones obtained from renewable sources such as poly(lactic acid) (PLA) have been considered [2]. Several papers are available regarding the mechanical behavior of natural fibers reinforced PLA composites, but only few deal with their creep behavior [3]. In the present work, the tensile creep behaviour of PLA based composites, containing flax and jute plain weave woven fabrics and produced by compression moulding technique, was investigated. Tensile creep tests were performed at different temperatures and applied stress. Fig. 1 shows the dimensionless (normalized) compliance as a function of creep time, for PLA and PLA/jute samples at both the test temperatures (40 and 60 °C). The results show that the creep behaviour of PLA is strongly influenced by the temperature. The presence of jute-based woven fabrics drastically modifies the creep response: at 40 °C, the compliance values are lower than those of the neat polymer; at 60 °C, the gap increases . In addition, the creep behaviour of the PLA/jute composite appears to not be influenced by the temperature increase. Regarding the PLA/flax composite (data not reported here), a significantly different behavior was found: flax woven fabric did not lead to a reduction of the creep compliance in comparison to PLA

The creep response of Polymer systems is typically investigated upon applying different loads, or under different temperature. However, no evidence exist of creep studies under different loads and temperatures and the simultaneos actionof accelerated weathering. In a previous paper La Mantia et al. [1] presented a new equipment that is able to subject polymer samples to creep under different loads, but also monitor the effect of photooxidation due to the temperature, humidity and UV irradiation, thus fully simulating the real operating conditions for polymer-based items. In tihs work a polyethylene/organomodified caly nanocompositehas been subjectedto combined creep-accelerated weathering conditions.

In many industrial processes the presence of zinc in the wastewater may represent an obstacle to its high efficient regeneration. This is the case of the treatment of spent pickling solutions aiming the recovery of hydrochloric acid via pyrohydrolysis techniques. Hydrochloric spent pickling solutions from steel processing contain relevant amount of metals such as iron (Fe) and zinc (Zn) that may significantly affect recovery of hydrochloric acid (HCl) through pyrohydrolysis. In fact, although Fe may be recovered as ferric oxide (Fe2O3) and does not have a substantial effect on pyrohydrolysis process, zinc chloride (ZnCl2) evaporating can occlude nozzles and stick to the pyrohydrolysis reactor walls, thereby contaminating the iron oxide product. Thus, efficient removal Zn is needed. Of note, Zn recovery is economically affordable and can provide commercially valuable by-products such as zinc chloride or sulfate. In this study, we present the results obtained within a laboratory experimental campaign to recover Zn and Fe from pickling liquors by means of liquid-liquid extraction adopting a suitable organic extractant, tributyl phosphate (TBP). In order to find out the best operative conditions leading to very high efficiencies, three main factors were investigated: the volume ratio between the organic extractant and the aqueous spent pickling liquor, the stirring time, and the percentage of TBP used (pure or variously diluted in kerosene). Furthermore, a parallel study was carried out for the analysis the efficiency of the stripping step, performed with the aim of regenerating TBP and recovering Zn and Fe by suitable aqueous stripping solutions. The results in terms of recovery yield and selectivity of Zn recovery over Fe ions were obtained and analyzed.

Class IV-S lupus nephritis (LN) is often associated with more necrosis and fewer subendothelial immune deposits compared to class IV-G LN, suggestive of the necrotising glomerular inflammation found in ANCA-associated vasculitis. ANCA are present in a significant proportion of patients with LN. The aim of this study was to determine whether ANCA are associated with distinct clinical and histopathological features of LN. 32 ANCA positive biopsies were compared to 222 ANCA negative biopsies from patients with LN. The majority of ANCA positive patients had anti-MPO antibodies (82%). Class IV-S LN and glomerular necrosis were more common (36% vs. 16%, p=0.0253 and 35% vs. 15%, p=0.025 respectively) and isolated Class V LN less common (10% vs. 29%, p=0.0282) in the ANCA positive group. ANCA positive patients had higher dsDNA titres (335u/ml vs. 52u/ml, p=0.00007), lower serum C4 concentration (0.125g/L vs. 0.15g/L, p=0.027) and higher serum creatinine (130µmol/L vs. 84µmol/L, p=0.047) at time of biopsy. Hence ANCA appear to influence the histological pattern of LN and are associated with worse baseline renal function and more active lupus serology. There was no significant difference in outcome between groups when matched for severity of disease and treatment using propensity scoring. Further studies are needed to examine whether ANCA in patients with LN have a pathogenic role and whether they are associated with worse renal outcomes or are simply a marker of more severe disease.

Nowadays, pyrohydrolysis techniques are widely applied for regeneration of spent pickling liquors providing an excellent environmental and economical strategy to the problem of waste disposal/recovery, also thanks to the high acid recovery efficiencies (>99%) achieved1. In fact, in these processes, iron chlorides are converted into iron oxides and hydrogen chloride at high temperature in spray roasting or fluidized bed reactors2. Though the state-of-the-art technologies have been successfully applied only to large scale plants, the development of small scale units, able to perform a delocalized regeneration of spent solutions where these latter are actually produced, would be strongly needed in order to minimize the transportation of hazardous spent pickling and fresh HCl solutions to/from pickling factories from/to large centralized regeneration plants. In the present work, a steady state simulation model for regeneration of spent pickling liquor via spray roasting has been developed, aiming at the analysis of performance of a small-scale unit. The simulation and optimization of the process has been carried out using ASPEN Plus simulator. A simplified model of the spray roaster, based on data collected from studies reported in the literature3, has been implemented and exported from ASPEN Custom Modeler. Solid recovery from roaster off-gases has been obtained by a cyclone and a Venturi scrubber, where the spent pickling liquor is concentrated prior to be sprayed into the reactor. Hydrogen chloride is absorbed in an adiabatic absorber, where a sub-azeotropic (18-20 wt%) hydrochloric solution is obtained. Prior to the stack, a scrubber is required to wash off the exhaust gases. Several parametric studies have been performed. Different designs of solid separators have been compared in order to investigate the particulate separation efficiency of the process, while absorption column’s packing types and rinse water flowrates have been varied in order to investigate their effects on HCl recovery and acid gas emissions.

Caspase-8 (casp-8) is well known as an initiator caspase involved in cell death signalling, although its activity in many cancer cell types seems to work under non-apoptotic conditions. Moreover, in several types of cancer, casp-8 is only rarely mutated and often its expression is very elevated. Since cancer cell growth also depends on evasion of apoptosis, the upregulation of casp-8 in tumours may suggest one or more non-apoptotic roles (1). Here we report our recent studies carried out in MDA-MB-231 cells, derived from clinically aggressive forms of Triple-Negative Breast Cancer, where we have assessed the non-canonical roles of casp-8. Firstly, we evaluated casp-8 mRNA and protein levels in MDA-MB-231 cells, demonstrating that they were upregulated with respect to HMEC (normal Human Mammalian Epithelial Cells). Thereafter, to assess the role of casp-8, we silenced it by small interfering-RNA. Interestingly casp-8-knockdown, strongly decreased MDA-MB-231 cell growth by delaying G0/G1- to S-phase transition and increasing p21, p27 and hypophosphorylated/active form of pRb levels. No effects were evidenced on cell viability. To assess the metastatic capacity of MDA-MB-231 cells, the gene expression profiles of the relative markers after casp-8 knockdown were also measured. Surprisingly the expression of a number of genes and/or proteins such as VEGFA, C-MYC, CTNNB1, HMGA2, CXCR4, KLF4, VERSICAN V1 and MMP2 potently increased accompanied by migratory and metastatic capacities of cells, as shown by wound healing and matrigel assays. We suggest that among these genes, KLF4, a transcriptional factor with a dual role (activator and repressor), and responsible for p21 and p27 induction, could play critical roles (2). Casp-8 through KLF4 down-regulation, could manage the expression of critical proliferative and migratory/invasive genes. We suggest that these unusual roles played by casp-8 in MDA-MB-231 cells, should be better explored, in order to identify it as a molecular therapeutic target. References 1. Stupack DG. Caspase-8 as a Therapeutic Target in Cancer. Cancer Lett 332:133–140, 2013. 2. Tiwari N et al. Klf4 Is a Transcriptional Regulator of Genes Critical for EMT, Including Jnk1 (Mapk8). PLoS One 8, 2013.

Dati non univoci sono riportati in letteratura sul ruolo della dislipidemia nello sviluppo dell’ipertrofia ventricolare sinistra. Scopo del nostro studio, è stato quello di valutare le potenziali associazioni dei principali parametri lipidici con la massa ventricolare sinistra (LVM) in pazienti con ipertensione essenziale (EHs). Abbiamo arruolato 724 soggetti con EH (età media 45±12 anni; 63% maschi), senza complicanze cardiovascolari e non trattati con farmaci ipolipemizzanti. In tutti i soggetti dono stati dosati la colesterolemia totale (Tchol), la trigliceridemia (TG) e il colesterolo HDL (HDLc). Il colesterolo LDL (LDLc) è stato stimato con la formula di Friedewald ed è stato calcolato il colesterolo nonHDLc. Inoltre, sono stati eseguiti un monitoraggio della pressione arteriosa delle 24 ore ed un ecocardiogramma. La LVM è stata indicizzata per la superficie corporea (LVMI). Nessuna correlazione statisticamente significativa è stata osservata tra Tchol, LDLc e nonHDLc e la LVMI. Abbiamo rilevato correlazioni significative della LVMI con l’HDLc (r=-0.14, p

early vascular aging

Recent data suggest that renal hemodynamic parameters obtained by duplex Doppler sonography, especially the intrarenal resistive index (RI), may be associated with systemic vascular changes in some groups of patients. However, conflicting data exist about the relationship between aortic stiffness and RI in autoimmune disease, like systemic lupus erythematosus, characterized by high and early incidence of atherosclerotic disease. The aim of this study was to evaluate the relationship between RI and arterial stiffness, assessed by aortic pulse wave velocity (aPWV), and carotid atherosclerosis, evaluated by intimal medial thickness measurement (IMT) in patients with SLE. DESIGN: Cross-sectional study. METHODS: We enrolled 39 SLE subjects (mean age: 39 years ), 35 women and 4 men. Each patient has been underwent to assessment of ultrasonographic renal RI, IP, measurement of aPWV through oscillometric device, and ultrasound evaluation of carotid IMT. RESULTS: IR correlated significantly with aortic PWV(r: 0,44; p=0,006), and with carotid IMT(r: 0,37; p=0,02) in the study population. The first correlation has remained significant after correction for age and mean arterial pressure. 12 patients have shown aPWV value more than 10 m/sec, that identifies who has more cardiovascular risk. In adding to this, in this group of patients IR levels were higher than in the patients with aPWV less then 10 m/sec. CONCLUSIONS Our results seems to suggest that, as previously demonstrated in other populations, the RI may be considered as a marker of systemic vascular changes and probably a predictor of cardiovascular risk also in SLE patients.

Il ruolo dell’iperuricemia asintomatica quale fattore in grado di favorire in modo indipendente la progressione della malattia renale cronica rimane controverso. Inoltre, gli studi finalizzati a valutare l’influenza della terapia ipouricemizzante sulla evoluzione delle nefropatie croniche sono poco numerosi e hanno dato risultati contrastanti. Scopo del nostro studio osservazionale è stato quello di analizzare retrospettivamente l'effetto del trattamento con allopurinolo, sul declino del filtrato glomerulare, in pazienti ipertesi con insufficienza renale cronica di grado moderato-severo. Sono stati pertanto selezionati 22 pazienti trattati con allopurinolo (A) (100-300 mg/die) che sono stati confrontati con 44 soggetti non sottoposti a trattamento con ipouricemizzanti (B) ed appaiati con il gruppo in terapia con allopurinolo per quanto attiene a filtrato glomerulare stimato (eGFR) , età, sesso e valori pressori. Dopo un follow-up medio di 16 mesi, nessuna differenza è stata osservata tra i due gruppi per quanto riguarda sia la rapidità del declino del eGFR (A: -6.8 ± 11.6 ml/min/1.73 m2; B: -4.2 ± 9.3 ml/min/1.73 m2), sia per quanto attiene alla percentuale di soggetti che hanno manifestato una riduzione del eGFR maggiore della mediana di distribuzione di tale parametro (A: 59%; B: 41%; p =0.16). L'analisi di regressione logistica multipla ha confermato, anche dopo correzione per potenziali fattori confondenti, l'assenza di un significativo impatto dell'allopurinolo sul declino del filtrato glomerulare durante il periodo di osservazione ed ha mostrato che le variabili associate in maniera indipendente al decremento del GFR erano la presenza di proteinuria ed il GFR alla valutazione basale. I nostri dati non supportano i risultati di precedenti studi che avevano evidenziato un effetto nefroprotettivo dell’allopurinolo. Ulteriori e più ampi studi di tipo randomizzato e controllato sono necessari per comprendere se trattare farmacologicamente i soggetti con iperuricemia asintomatica al fine di preservare la funzione renale.