La nutrizione-idratazione artificiale è terapia? All'interfaccia tra scienza, diritto e bioetica, il fine vita in Italia, secondo una prospettiva di comunicazione della scienza post-accademica e Science&Technologies Studies (STS)

The question “artificial nutrition and hydration (ANH) is therapy or not?” is one of the key point of end-of-life issues in Italy, since it was (and it is also nowadays) a strategic and crucial point of the Italian Bioethics discussion about the last phases of human life: determining if ANH is therapy implies the possibility of being included in the list of treatments that could be mentioned for refusal within the living will document. But who is entitled to decide and judge if ANH is a therapy or not? Scientists? The Legislator? Judges? Patients? This issue at first sight seems just a matter of science, but at stake there is more than a scientific definition. According to several scholars, we are in the era of post-academic Science, in which Science broaden discussion, production, negotation and decision to other social groups that are not just the scientific communities. In this process, called co-production, on one hand scientific knowledge derives from the interaction between scientists and society at large. On the other hand, science is functional to co-production of social order. The continuous negotation on which science has to be used in social decisions is just the evidence of the mirroring negotation for different way to structure and interpret society. Thus, in the interaction between Science and Law, deciding what kind of Science could be suitable for a specific kind of Law, envisages a well defined idea of society behind this choice. I have analysed both the legislative path (still in progress) in the living will act production in Italy and Eluana Englaro’s judicial case (that somehow collapsed in the living will act negotiation), using official documents (hearings, texts of the official conference, committees comments and ruling texts) and interviewing key actors in the two processes from the science communication point of view (who talks in the name of science? Who defines what is a therapy? And how do they do?), finding support on the theoretical framework of the Science&Technologies Studies (S&TS).

Investigating the role of single point mutations in the human proteome: a computational study

In the post genomic era with the massive production of biological data the understanding of factors affecting protein stability is one of the most important and challenging tasks for highlighting the role of mutations in relation to human maladies. The problem is at the basis of what is referred to as molecular medicine with the underlying idea that pathologies can be detailed at a molecular level. To this purpose scientific efforts focus on characterising mutations that hamper protein functions and by these affect biological processes at the basis of cell physiology. New techniques have been developed with the aim of detailing single nucleotide polymorphisms (SNPs) at large in all the human chromosomes and by this information in specific databases are exponentially increasing. Eventually mutations that can be found at the DNA level, when occurring in transcribed regions may then lead to mutated proteins and this can be a serious medical problem, largely affecting the phenotype. Bioinformatics tools are urgently needed to cope with the flood of genomic data stored in database and in order to analyse the role of SNPs at the protein level. In principle several experimental and theoretical observations are suggesting that protein stability in the solvent-protein space is responsible of the correct protein functioning. Then mutations that are found disease related during DNA analysis are often assumed to perturb protein stability as well. However so far no extensive analysis at the proteome level has investigated whether this is the case. Also computationally methods have been developed to infer whether a mutation is disease related and independently whether it affects protein stability. Therefore whether the perturbation of protein stability is related to what it is routinely referred to as a disease is still a big question mark. In this work we have tried for the first time to explore the relation among mutations at the protein level and their relevance to diseases with a large-scale computational study of the data from different databases. To this aim in the first part of the thesis for each mutation type we have derived two probabilistic indices (for 141 out of 150 possible SNPs): the perturbing index (Pp), which indicates the probability that a given mutation effects protein stability considering all the “in vitro” thermodynamic data available and the disease index (Pd), which indicates the probability of a mutation to be disease related, given all the mutations that have been clinically associated so far. We find with a robust statistics that the two indexes correlate with the exception of all the mutations that are somatic cancer related. By this each mutation of the 150 can be coded by two values that allow a direct comparison with data base information. Furthermore we also implement computational methods that starting from the protein structure is suited to predict the effect of a mutation on protein stability and find that overpasses a set of other predictors performing the same task. The predictor is based on support vector machines and takes as input protein tertiary structures. We show that the predicted data well correlate with the data from the databases. All our efforts therefore add to the SNP annotation process and more importantly found the relationship among protein stability perturbation and the human variome leading to the diseasome.

Innovative Strategies for the Synthesis of Biologically Active Small Molecules

The post genomic era, set the challenge to develop drugs that target an ever-growing list of proteins associated with diseases. However, an increase in the number of drugs approved every year is nowadays still not observed. To overcome this gap, innovative approaches should be applied in drug discovery for target validation, and at the same time organic synthetic chemistry has to find new fruitful strategies to obtain biologically active small molecules not only as therapeutic agents, but also as diagnostic tools to identify possible cellular targets. In this context, in view of the multifactorial mechanistic nature of cancer, new chimeric molecules, which can be either antitumor lead candidates, or valuable chemical tools to study molecular pathways in cancer cells, were developed using a multitarget-directed drug design strategy. According to this approach, the desired hybrid compounds were obtained by combining in a single chemical entity SAHA analogues, targeting histone deacetylases (HDACs), with substituted stilbene or terphenyl derivatives able to block cell cycle, to induce apoptosis and cell differentiation and with Sorafenib derivative, a multikinase inhibitor. The new chimeric derivatives were characterized with respect to their cytotoxic activity and their effects on cell cycle progression on leukemia Bcr-Abl-expressing K562 cell lines, as well as their HDACs inhibition. Preliminary results confirmed that one of the hybrid compounds has the desired chimeric profile. A distinct project was developed in the laboratory of Dr Spring, regarding the synthesis of a diversity-oriented synthesis (DOS) library of macrocyclic peptidomimetics. From a biological point of view, this class of molecules is extremely interesting but underrepresented in drug discovery due to the poor synthetic accessibility. Therefore it represents a valid challenge for DOS to take on. A build/couple/pair (B/C/P) approach provided, in an efficient manner and in few steps, the structural diversity and complexity required for such compounds.

Genomic and non genomic effects of elevated concentration of anabolic steroids in human neuronal cells

Nandrolone and other anabolic androgenic steroids (AAS) at elevated concentration can alter the expression and function of neurotransmitter systems and contribute to neuronal cell death. This effect can explain the behavioural changes, drug dependence and neuro degeneration observed in steroid abuser. Nandrolone treatment (10-8M–10-5M) caused a time- and concentration-dependent downregulation of mu opioid receptor (MOPr) transcripts in SH-SY5Y human neuroblastoma cells. This effect was prevented by the androgen receptor (AR) antagonist hydroxyflutamide. Receptor binding assays confirmed a decrease in MOPr of approximately 40% in nandrolonetreated cells. Treatment with actinomycin D (10-5M), a transcription inhibitor, revealed that nandrolone may regulate MOPr mRNA stability. In SH-SY5Y cells transfected with a human MOPr luciferase promoter/reporter construct, nandrolone did not alter the rate of gene transcription. These results suggest that nandrolone may regulate MOPr expression through post-transcriptional mechanisms requiring the AR. Cito-toxicity assays demonstrated a time- and concentration dependent decrease of cells viability in SH-SY5Y cells exposed to steroids (10-6M–10-4M). This toxic effects is independent of activation of AR and sigma-2 receptor. An increased of caspase-3 activity was observed in cells treated with Nandrolone 10-6M for 48h. Collectively, these data support the existence of two cellular mechanisms that might explain the neurological syndromes observed in steroids abuser.

La scuola di Gundēšābūr. La conoscenza del corpo umano (anatomia e fisiologia) e la trasmissione delle teorie medico-scientifiche nel mondo sasanide e post-sasanide.

Questo lavoro traccia un quadro della diffusione e trasmissione delle conoscenze riguardanti l’anatomia e la fisiologia del corpo umano nel mondo iranico in età sasanide (III-VII sec. d.C.). La tesi analizza il ruolo delle scuole di medicina in territorio iranico, come quelle sorte a Nisibi e Gundēšābūr, delle figure dei re sasanidi interessati alla filosofia e alla scienza greca, e dei centri di studio teologico e medico che, ad opera dei cristiani siro-orientali, si fecero promotori della conoscenza medico-scientifica greca in terra d’Iran.