Multi-swarm multi-objective optimization based on a hybrid strategy

Multi-objective optimization is a very competitive issue that emerges naturally in most real world problems. It is concerned with the optimization of conflicting objectives in multi-objective problems. The multi-objective problem treats with tradeoff solutions in order to satisfy all objectives. An extensive variety of algorithms has been developed to solve multi-objective optimization problems. In this paper, we presents a multi-swarm multi-objective intelligence-based algorithm enhanced with a hybrid strategy between decomposition and dominance (MSMO/2D) to improve convergence and diversity by splitting the primary swarm into a number of sub-swarms. The proposed algorithm is applied to fourteen standard problems and compared with two of the most familiar multi-objective optimization algorithms MOEA/D and D2MOPSO. The experimental results give evidence that the multi-swarm armed by the hybrid strategy constitutes a better alternative for multi-objective optimization problems. Keywords: Multi-objective, Multi-swarm, Decomposition, Dominanc

Cross-talk between calpain and caspase-3/-7 in cisplatin-induced apoptosis of melanoma cells: a major role of calpain inhibition in cell death protection and p53 status

4noreservedThe contribution of different proteolytic systems, in particular calpains and effector caspases, in apoptotic cell death is still controversial. In this paper, we show that during cisplatin-induced apoptosis of human metastatic melanoma cells, calpain activation, as measured in intact cells by two different fluorescent substrates, is an early event, taking place well before caspase-3/-7 activation, and progressively increasing during 48 h of treatment. Such activation appears to be independent from any intracellular calcium imbalance; in fact, an increase of cytosolic calcium along with emptying of the reticular stores occur only at very late stages, uniquely in frankly apoptotic, detached cells. Calpain activation proves to be an early and crucial event in the apoptotic machinery, as demonstrated by the significant protection of cell death in samples co-treated with the calpain inhibitors, MDL 28170, calpeptin and PD 150606, where a variable but significant reduction of both caspase-3/-7 activity and cell detachment is observed. Consistently, such a protective effect can be at least partially due to the impairment of cisplatin-induced p53 activation, occurring early in committed, preapoptotic cells. Furthermore, in late apoptotic cells, calpain activity is also responsible for the formation of a novel p53 proteolytic fragment (approximate to 26 kDa), whose function is so far to be elucidated.mixedDel Bello, Barbara; Moretti, Daniele; Gamberucci, Alessandra; Maellaro, EmiliaDel Bello, Barbara; Moretti, Daniele; Gamberucci, Alessandra; Maellaro, Emili