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The paper presents part of the results of two researches focused on an area situated in Central Italy: the European Project “Radar” (Raising Awareness on renewable energy Developing Agro-eneRgetic chain models) and the “energy and environmental plan for the consortium of the Commons in the mountain area of Esino-Frasassi”. This area is characterized by a huge availability of forestry biomass and, in a lower measure, of agricultural discards. This work presents a technical-economic study for a cogenerative plant applied to a public building with a small thermal demand. The choice of the best energy conversion system mainly depends on two factors: the availability of biomass and the user demand. Microturbine and Stirling engine are the technologies which better matches both with the size of the final user and with the availability of solid biomass. The biomass used comes from residual of olive tree pruning. The technical analysis is then followed by an economic one which shows how fundamental are the economic incentives for renewable sources (provided by Italian legislation, in this case) in order to make the technology appealing for energy investors; in particular the feed-in tariff mechanism is studied. The energy and economic analysis are carried out, both for microturbine and Stirling engine, considering different working hours over the years, different operating modes (with or without cogeneration) and three different costs of the solid biomass. Furthermore, the economic analysis points out that, beside the crucial role of incentive, the economic feasibility of solid biomass plant depends on the cost of biomass, the annual operating hours and the opportunity of recovery discharged heat in cogenerative application. In particular, the cost of biomass is, before everything else, the result of an agreement between the manager of the energy conversion plant and the suppliers., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 2340-2346

Aims Diabetic cardiomyopathy is a multifactorial disease characterized by an early onset of diastolic dysfunction (DD) that precedes the development of systolic impairment. Mechanisms that can restore cardiac relaxation improving intracellular Ca2+ dynamics represent a promising therapeutic approach for cardiovascular diseases associated to DD. Istaroxime has the dual properties to accelerate Ca2+ uptake into sarcoplasmic reticulum (SR) through the SR Ca2+ pump (SERCA2a) stimulation and to inhibit Na+/K+ ATPase (NKA). This project aims to characterize istaroxime effects at a concentration (100 nmol/L) marginally affecting NKA, in order to highlight its effects dependent on the stimulation of SERCA2a in an animal model of mild diabetes. Methods and results Streptozotocin (STZ) treated diabetic rats were studied at 9 weeks after STZ injection in comparison to controls (CTR). Istaroxime effects were evaluated in vivo and in left ventricular (LV) preparations. STZ animals showed 1) marked DD not associated to cardiac fibrosis, 2) LV mass reduction associated to reduced LV cell dimension and T-tubules loss, 3) reduced LV SERCA2 protein level and activity and 4) slower SR Ca2+ uptake rate, 5) LV action potential (AP) prolongation and increased short-term variability (STV) of AP duration, 6) increased diastolic Ca2+, and 7) unaltered SR Ca2+ content and stability in intact cells. Acute istaroxime infusion (0.11 mg/kg/min for 15 min) reduced DD in STZ rats. Accordingly, in STZ myocytes istaroxime (100 nmol/L) stimulated SERCA2a activity and blunted STZ-induced abnormalities in LV Ca2+ dynamics. In CTR myocytes, istaroxime increased diastolic Ca2+ level due to NKA blockade albeit minimal, while its effects on SERCA2a were almost absent. Conclusions SERCA2a stimulation by istaroxime improved STZ-induced DD and intracellular Ca2+ handling anomalies. Thus, SERCA2a stimulation can be considered a promising therapeutic approach for DD treatment. Translational perspective Deficient sarcoplasmic reticulum (SR) Ca2+ uptake has been identified in cardiomyocytes from failing human hearts with impaired diastolic relaxation (e.g. diabetic hearts) and has been associated with a decreased SERCA2a expression and activity and/or with a higher SERCA2a inhibition by phospholamban. Thus, SERCA2a may represent a pharmacological target for interventions aimed at improving cytosolic Ca2+ compartmentalization into the SR to limit diastolic dysfunction pathologies. In this context, istaroxime is the first-in-class luso-inotropic agent targeting SERCA2a that has already demonstrated its efficacy in clinical trials and may be useful to clarify the relevance of SERCA2a stimulation in controlling cytosolic Ca2+ level.

Rationale: Aging in the heart is a gradual process, involving continuous changes in cardiovascular cells, including cardiomyocytes (CMs), namely cellular senescence. These changes finally lead to adverse organ remodeling and resulting in heart failure. This study exploits CMs from human induced pluripotent stem cells (iCMs) as a tool to model and characterize mechanisms involved in aging. Methods and Results: Human somatic cells were reprogrammed into human induced pluripotent stem cells and subsequently differentiated in iCMs. A senescent-like phenotype (SenCMs) was induced by short exposure (3 hours) to doxorubicin (Dox) at the sub-lethal concentration of 0.2 µM. Dox treatment induced expression of cyclin-dependent kinase inhibitors p21 and p16, and increased positivity to senescence-associated beta-galactosidase when compared to untreated iCMs. SenCMs showed increased oxidative stress, alteration in mitochondrial morphology and depolarized mitochondrial membrane potential, which resulted in decreased ATP production. Functionally, when compared to iCMs, SenCMs showed, prolonged multicellular QTc and single cell APD, with increased APD variability and delayed afterdepolarizations (DADs) incidence, two well-known arrhythmogenic indexes. These effects were largely ascribable to augmented late sodium current (INaL) and reduced delayed rectifier potassium current (Ikr). Moreover sarcoplasmic reticulum (SR) Ca2+ content was reduced because of downregulated SERCA2 and increased RyR2-mediated Ca2+ leak. Electrical and intracellular Ca2+ alterations were mostly justified by increased CaMKII activity in SenCMs. Finally, SenCMs phenotype was furtherly confirmed by analyzing physiological aging in CMs isolated from old mice in comparison to young ones. Conclusions: Overall, we showed that SenCMs recapitulate the phenotype of aged primary CMs in terms of senescence markers, electrical and Ca2+ handling properties and metabolic features. Thus, Dox-induced SenCMs can be considered a novel in vitro platform to study aging mechanisms and to envision cardiac specific anti-aging approach in humans.

Avidities of human monoclonal antibodies derived from an adult immunized with pneumococcal polysaccharide vaccine Angela Lombardi1, Srinivasa Bandi2, Jeremy T. Rahkola2, Luciana Rossi1, Edward N. Janoff2 Antonella Baldi1 1 Faculty of Veterinary Medicine, Department of Health, Animal Science and Food Safety Via Celoria 10 20133 Università degli Studi di Milano, Milan. 2 School of Medicine Division of Infectious Disease 12700 East 19th Avenue, Box B168 Aurora, CO 80045 University of Colorado Anschutz Medical Campus, Aurora Denver, USA. Plant based vaccines provide an instructive opportunity for immunologists. We have developed a plant-based oral vaccine against verocytotoxin–producing E.coli (VTEC) in piglets (Rossi et. al 2014). We engineered two independent lines of Nicotiana tabacum plants for the seed-specific expression of VTEC antigens, represented by the major subunit FedA of the F18 adhesive fimbriae and the B-subunit of VT2e toxin respectively (Rossi et. al. 2013). Edible vaccines in particular are of interest as they are able to stimulate the mucosal immune system to produce secretory IgA (S-IgA) at mucosal surfaces and, potentially IgG in the blood. The quality of the antibodies, such as avidity, should be considered in evaluating the efficacy of these vaccines. To develop this area, we determined avidity (strength of antibody-antigen binding) of IgG to the capsule of another mucosal pathogen, Streptococcus pneumoniae. Using pneumococcal capsule-specific IgG human monoclonal antibodies (hMAb) cloned from single cells of a subject immunized with pneumococcal vaccine, we defined serotypes specificity and the avidity of these antibodies with ammonium thiocyanate (0, 4M, 2M, 1M 0.5M 0.025M) dissociation. IgG with lower avidity to the capsule are dissociated at lower NH4SCN levels, whereas IgG with higher affinity require higher levels. We identified a range of avidities for 11 hMAB’s (range X-Y MNH4SCN). We will evaluate the avidity of antibodies after immunization with edible vaccines against VTEC strain in piglets about which little in known, but as demonstrated in Granoff et al. the high-avidity antibodies are required in generating a more effective vaccine. Key words Edible vaccines, Nicotiana tabacum, VTEC strain, Avidity of antibody, Streptococcus pneumoniae, Monoclonal Antibody References Baxendale, H. E., Goldblatt, D., 2006. Correlation of Molecular Characteristics, Isotype, and In Vitro Functional Activity of Human Antipneumococcal Monoclonal Antibodies. Infect. Immun. 74:1025–1031. Rossi, L., Dell’Orto, V., Vagni, S., Sala, V., Reggi, S., Baldi, A., 2014. Protective effect of oral administration of transgenic tobacco seeds against verocytotoxic Escherichia coli strain in piglets. Vet Res Comm 38 (1), 39-49. Rossi, L., Di Giancamillo, A., Reggi, S., Domeneghini, C., Baldi, A., Sala, V., Dell’Orto, V., Coddens, A., Cox, E., Fogher, C., 2013. Expression of porcine verocytotoxic Escherichia coli antigens in tobacco seeds and evaluation of gut immunity after oral administration in mouse model” JV 14(3), 263-270., International Journal of Health, Animal Science and Food Safety, Vol 3, No 1s (2016)