Computational investigation of the Plasmodium falciparum fatty acid biosynthetic pathway toward the discovery of novel antimalarials

The structural peculiarities of a protein are related to its biological function. In the fatty acid elongation cycle, one small carrier protein shuttles and delivers the acyl intermediates from one enzyme to the other. The carrier has to recognize several enzymatic counterparts, specifically interact with each of them, and finally transiently deliver the carried substrate to the active site. Carry out such a complex game requires the players to be flexible and efficiently adapt their structure to the interacting protein or substrate. In a drug discovery effort, the structure-function relationships of a target system should be taken into account to optimistically interfere with its biological function. In this doctoral work, the essential role of structural plasticity in key steps of fatty acid biosynthesis in Plasmodium falciparum is investigated by means of molecular simulations. The key steps considered include the delivery of acyl substrates and the structural rearrangements of catalytic pockets upon ligand binding. The ground-level bases for carrier/enzyme recognition and interaction are also put forward. The structural features of the target have driven the selection of proper drug discovery tools, which captured the dynamics of biological processes and could allow the rational design of novel inhibitors. The model may be perspectively used for the identification of novel pathway-based antimalarial compounds.

Well-being, distress and health status in a population of adolescent students

The present work explores the psychosocial issues emerging from a large cross-sectional study aimed to assess the prevalence, clinical manifestations, and psychosocial correlates of hyperandrogenism in a population of Italian high school students. Participants were 1804 adolescents, aged between 15 and 19 years, who volunteered to fill in a package of self-report questionnaires (including the Psychosocial Index, the Symptom Questionnaire and Ryff’s Psychological Well-Being scales for the assessment of psychological aspects) and undergo a comprehensive physical examination. Significant gender differences were found with regard to psychological distress, with females reporting higher scores compared with males, but not on well-being dimensions. The relationships of well-being to distress were found to be complex. Although inversely associated, well-being and ill-being appeared to be distinct domains of mental functioning. The evaluation of the moderating effects of well-being in the association between stress and psychological distress indicated that well-being may act as a protective factor, contributing to less pronounced psychological distress as stress levels increased. Higher rates of somatic complaints were found among current smokers. However, substance use (i.e., smoking and drug use) was also found to be positively associated with some well-being dimensions. A considerable number of participants were found to present with disordered eating symptoms, particularly females, and associated higher stress levels and lower quality of life. Sport activities were found to favourably affect psychological health. As to clinical signs of hyperandrogenism, a significant impairment in psychosocial functioning was found among females, whereas no effects on psychological measures could be detected among males. Subgroups of adolescents with distinct clinical and psychological characteristics could be identified by means of cluster analysis. The present study provides new insights into better understanding of the complex relationships between well-being, distress and health status in the adolescent population, with important clinical implications.

The role of proactive coping strategies and perceived health status for Social well-being and life-project in old age.

The latter part of the 20th century was a period characterized by a fundamental demographic transition of western society. This substantial and structural demographic change proposes several challenges to contemporary society and fosters the emergence of new issues and challenges. Among these, none is more crucial than the comprehension of the mechanisms and the processes that lead people to positive aging. Rowe and Kahn’s model of successful aging highlights the interplay between social engagement with life, health, and functioning for a positive aging experience. Other systemic models of successful aging (Kahana et al., 1996; 2003; Stevernik et al., 2006) emphasize the role of internal and external resources for attaining positive aging. Among these, the proactive coping strategies are indicated as important active strategies for avoiding the depletion of resources, counterbalancing the declines and maintaining social and civic involvement. The study has analyzed the role of proactive coping strategies for two facets of positive aging, the experience of a high social well-being and the presence of personal projects in fundamental life domains. As expected, the proactive coping strategies, referred to as the active management of the environment, the accumulation of resources and the actualization of human potentials are confirmed as positive predictors of high level of social well-being and of many personal projects focused on family, culture, leisure time, civic and social participation. Perceived health status give a significant contribution only to the possession of many personal projects. Gender and level of school education give also a significant contribution to these two dimensions of positive aging, highlighting how positive aging is rooted not only in the possession of personal resources, but also in historical models of education and in positive longitudinal chains related to early development.