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Resumen Introducción: A nivel latinoamericano el suicidio en jóvenes y adolescente representa una problemática grave, por lo que es necesario trabajar en su prevención. En ese sentido, este trabajo presenta una revisión teórica narrativa sobre la temática. Objetivo: Conocer las principales experiencias de prevención de la suicidalidad en jóvenes y adolescentes de Latinoamérica en los últimos 15 años. Método: Se revisaron y analizaron 44 estudios empíricos, realizando búsquedas bibliográficas en revistas científicas indexadas en Scopus, Scielo, WoS, REDALYC y ERIH PLUS y motores de búsqueda como Google Académico y EBSCO. Resultados: Los hallazgos obtenidos en los 44 estudios se organizaron en tres categorías: 1) diagnósticos sobre suicidalidad realizados en población juvenil y adolescente; 2) intervenciones psicoterapéuticas destinadas a tratamiento en suicidalidad; y 3) intervenciones en base a programas, estrategias y técnicas enfocadas en la prevención del suicidio juvenil y adolescente. Discusión: Los principales diagnósticos asociados a la suicidalidad están vinculados a disfuncionalidades emocionales, donde las mujeres son las principales afectadas, la familia y el entorno surgen como principales factores protectores o de riesgo dependiendo de su funcionalidad y cohesión. Además, las intervenciones más valoradas están asociadas a los modelos clásicos de psicoterapia y las estrategias psicoeducativas aparecen como los principales focos de los programas preventivos. Conclusión: Por la multifactoriedad del fenómeno, se debería realizar un cambio paradigmal en el enfrentamiento de la suicidalidad. Abstract Introduction: At the Latin American level, suicide in young people and adolescents represents a serious problem, so it is necessary to work on its prevention. In this sense, this work presents a narrative theoretical review on the subject. Objective: To know the main experiences of suicide prevention in young people and adolescents in Latin America in the last 15 years. Method: 44 empirical studies were reviewed and analyzed, performing bibliographic searches in scientific journals indexed in Scopus, Scielo, WoS, REDALYC and ERIH PLUS and search engines such as Google Scholar and EBSCO. Results: The findings obtained in the 44 studies were organized into three categories: 1) diagnoses of suicidality made in the youth and adolescent population; 2) psychotherapeutic interventions aimed at treating suicidality; and 3) interventions based on programs, strategies and techniques focused on the prevention of youth and adolescent suicide. Discussion: The main diagnoses associated with suicidality are linked to emotional dysfunctionalities, where women are the main affected, the family and the environment appear as the main protective or risk factors depending on their functionality and cohesion. In addition, the most valued interventions are associated with the classic models of psychotherapy and psychoeducational strategies appear as the main focuses of preventive programs. Conclusion: Due to the multifactorial nature of the phenomenon, a paradigm shift should be made in the confrontation of suicidality.

La enfermedad de Chagas es una enfermedad tropical desatendida causada por el parásito protozoario Trypanosoma cruzi que afecta a más de 8 millones de personas en todo el mundo, especialmente en América Latina. El tratamiento implica la administración de fármacos tripanocidas, benznidazol (considerado el tratamiento de primera línea) o nifurtimox. Si bien se ha demostrado que el benznidazol es eficaz y seguro, y se ha utilizado durante los últimos 50 años, el conocimiento farmacológico de este fármaco sigue siendo limitado, en particular en lo que respecta a sus vías metabólicas, metabolitos y farmacocinética. Dado que el tratamiento requiere períodos de administración prolongados de más de 30 días, suele ser común la aparición de toxicidad significativa que lleva a la suspensión del tratamiento. Es sumamente crucial comprender la farmacocinética del benznidazol, incluido su metabolismo y distribución, para comprender los mecanismos subyacentes a estas toxicidades a fin de mejorar los regímenes de tratamiento. Además, las diferencias con el metabolismo parasitario del benznidazol podrían contribuir a comprender sus mecanismos de acción. En el trabajo contenido en esta tesis, se presentan los resultados de mis estudios de doctorado, encaminados a identificar y describir los principales metabolitos del benznidazol, algunos nunca reportados previamente, en humanos y en el parásito. Además, se presenta evidencia del metabolismo hepático in vitro del benznidazol en varias especies de mamíferos. Para describir la biodistribución del benznidazol y sus metabolitos,se realizó un estudio farmacocinético del benznidazol en un modelo de infección aguda murina de la enfermedad de Chagas. Los resultados muestran una rápida absorción y eliminación del fármaco y prueban la presencia de benznidazol y varios de sus metabolitos en diferentes órganos. En este estudio también se describe el metabolismo del benznidazol en el parásito en fase infecciosa, concluyendo que una de las principales diferencias entre el metabolismo de los mamíferos estudiados y los tripomastigotes es la producción de metabolitos que se conjugan con ácido glucurónico, reacción que requiere enzimas no disponibles en T. cruzi. Finalmente, el estudio preliminar de biomarcadores predictivos de reacciones adversas de benznidazol y nifurtimox sienta las bases para estudios futuros, ya que se detectaron algunos biomarcadores potenciales que requerirán confirmación, pero principalmente se identificaron las principales cuestiones del proceso que aumentarían la variabilidad de los resultados y que deben mejorarse para obtener mayor precisión y consistencia en los mismos. Chagas disease is a tropical neglected disease caused by the protozoan parasite Trypanosoma cruzi and affects more than 8 million people across the world but specially in Latin America. Treatment involves administration of one of two trypanocidal drugs, benznidazole (currently considered the first line treatment) or nifurtimox. While benznidazole has been shown to be effective and safe, and has been used for almost 50 years, pharmacological knowledge of this drug remains limited, particularly regarding its metabolic pathways, actual metabolites and pharmacokinetics. Since Chagas disease treatment requires long administration periods (i.e., more than 30 days), significant toxicity is common, often leading to treatment suspension; it is extremely crucial to understand benznidazole pharmacokinetics including its metabolism and distribution to understand the mechanisms underlying its toxicities, and to improve treatment regimes. Furthermore, differences in parasite benznidazole metabolism could contribute to understand its mechanisms of action. In the work contained in this thesis, I present the results of the experiments I performed during my PhD studies, aimed at identifying and describing the main metabolites of benznidazole, some never reported before, in humans and in the parasite. Moreover, we present evidence of in vitro hepatic metabolism of benznidazole in several mammalian species. In order to describe the biodistribution of benznidazole and its metabolites, we have performed a pharmacokinetic study of benznidazole in an acute murine infection model of Chagas disease. The results show rapid drug absorption and elimination and prove the presence of benznidazole and several of its metabolites in different organs. We also describe benznidazole metabolism in the parasite, in its infective trypomastigote form, and conclude that one of the main differences between mammalian and trypomastigote metabolism is the production of metabolites that become conjugated with glucuronic acid, which requires enzymes not available in T. cruzi. Finally, the preliminary study of predictive biomarkers of adverse reactions from benznidazole and nifurtimox lay the foundation for future studies, since we have detected some potential biomarkers that will require confirmation, but mainly identified the issues and problems at different steps of the process that should be improved to obtain more accurate and consistent results. Fil: Rocco, Daniela Marisa. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.

Familial platelet disorder with propensity to myeloid malignancy (FPD/AML) is a rare autosomal dominant form of thrombocytopenia associated with an increased risk of myelodysplastic syndrome and acute myeloid leukemia (AML) caused by germline mutations in the hematopoietic transcription factor RUNX1. Molecular testing allowed us to identify mutations in 13 individuals from three families with inherited thrombocytopenia (IT). They had thrombocytopenia with platelet normal volume and variable expressivity of other morphological and functional defects of platelets, such as reduction of alpha-granules and expression of GPIa-IIa, decreased aggregation, increased level of serum thrombopoietin. In this cohort, only three patients developed AML, with an incidence relative lower than that reported in literature. Since this discrepancy could be explained by different criteria of enrolment (RUNX1 is regarded as a candidate gene only when thrombocytopenia is associated with AML), a systematic screening of RUNX1 in IT families would allow us to identify carriers and more precisely determine the leukemic risk. Yet, considering that recognition of families with FPD/AML is of fundamental importance in the choice of donors for hematopoietic stem cell transplantation, current recommendation includes molecular genetic testing of genes (RUNX1 but also ANKRD26, and ETV6) whose mutations not only are responsible for thrombocytopenia with normal platelet volume but also increase the risk of hematological cancers. Fil: De Rocco, Daniela. Institute for Maternal and Child Healt; Italia Fil: Melazzini, Federica. Policlinico San Matteo Foundation; Italia. University of Pavia; Italia Fil: Marconi, Caterina. Universidad de Bologna; Italia Fil: Pecci, Alessandro. Policlinico San Matteo Foundation; Italia. University of Pavia; Italia Fil: Bottega, Roberta. Università degli Studi di Trieste; Italia Fil: Gnan, Chiara. Institute for Maternal and Child Healt; Italia Fil: Palombo, Flavia. Universidad de Bologna; Italia Fil: Giordano, Paola Florencia. Universita Degli Studi Di Bari; Italia Fil: Coccioli, Maria Susanna. Hospital “D. Camberlingo; Italia Fil: Glembotsky, Ana Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Heller, Paula Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Seri, Marco. Universidad de Bologna; Italia Fil: Savoia, Anna. Università degli Studi di Trieste; Italia. Institute for Maternal and Child Healt; Italia Fil: Noris, Patrizia. University of Pavia; Italia

Fanconi anemia (FA) is a rare genetic disease characterized by congenital malformations, aplastic anemia and increased risk of developing malignancies. FA is genetically heterogeneous as it is caused by at least 17 different genes. Among these, FANCA, FANCC, and FANCG account for approximately 85% of the patients whereas the remaining genes are mutated in only a small percentage of cases. For this reason, the molecular diagnostic process is complex and not always extended to all the FA genes, preventing the characterization of individuals belonging to rare groups.The FA genes were analyzed using a next generation sequencing approach in two unrelated families.The analysis identified the same, c.484_485del, homozygous mutation of FANCF in both families. A careful examination of three electively aborted fetuses in one family and one affected girl in the other indicated an association of the FANCF loss-of-function mutation with a severe phenotype characterized by multiple malformations.The systematic use of next generation sequencing will allow the recognition of individuals from rare complementation groups, a better definition of their clinical phenotypes, and consequently, an appropriate genetic counseling.

MYH9-related disease (MYH9-RD) is a rare autosomal dominant disorder caused by mutations in MYH9, the gene encoding the heavy chain of non-muscle myosin IIA. All patients present congenital macrothrombocytopenia and inclusion bodies in neutrophils. Some of them can also develop sensorineural deafness, presenile cataract, and/or progressive nephropathy leading to end-stage renal failure. We report four families, each with a novel mutation: two missense mutations, in exons 31 and 32, and two out of frame deletions in exon 40. They were associated with no bleeding diathesis, normal, or only slightly reduced platelet count and no extra-hematological manifestations, confirming that alterations of the tail domain cause a mild form of MYH9-RD with no clinically relevant defects.

2013/2014 2013/2014 La sindrome di Bernard-Soulier (BSS) è una rara piastrinopenia ereditaria causata da alterazioni a livello del complesso glicoproteico GPIb-IX-V, presente sulla membrana piastrinica e responsabile della adesione delle piastrine in seguito a danno vascolare. La BSS si trasmette come malattia autosomica recessiva (BBSA1) e i pazienti affetti presentano piastrine giganti e severi episodi di sanguinamento. Tuttavia in tempi recenti sono state descritte delle famiglie con una forma dominante nota come BSSA2. In questi pazienti la piastrinopenia è moderata e le piastrine presentano un volume leggermente aumentato. Finora sono state individuate solo 5 varianti in eterozigosi nel BSSA2:, 4 nel gene GP1BA e 1 in GP1BB. Fatta eccezione per p.Ala172Val del gene GP1BA che è relativamente frequente nella la popolazione Italiana, le altre 4 sono state descritte in singole famiglie. I pochi casi di cui disponiamo, soprattutto per la forma recessiva non ci permettono di avere informazioni sui meccanismi patogenetici e sulla sua evoluzione nel tempo. Per questo motivo è stato istituito un Consorzio Internazionale per lo studio della BSS grazie al quale è stato possibile raccogliere i dati clinici e molecolari di 132 famiglie. Tutte le informazioni sono state inserite in un database (BSS Consortium database) attualmente gestito dal nostro laboratorio e consultabile dai gruppi di studio che hanno aderito al Consorzio. Inoltre per aumentare le informazioni sulle varianti identificate nel BSSA1 abbiamo incrementato i dati molecolari delle famiglie del Consorzio con i dati di altre 79 famiglie descritte in letteratura, raggiungendo un totale di 211 famiglie. Tutte le mutazioni identificate in queste famiglie sono state poi inserite in un database pubblico disponibile in rete (LOVD: Leiden Open Variation Database). La raccolta e l’elaborazione dei dati ci ha permesso di chiarire alcuni aspetti clinici e molecolari della malattia. Tuttavia data l’eterogeneità genetica e l’elevata espressione fenotipica gli studi genotipo-fenotipo si sono rivelati difficili da eseguire. Nonostante le molte informazioni acquisite, il database risulta ancora incompleto e limitato; per questo motivo è necessario raccogliere nuovi casi e inserire assieme alle varianti anche i relativi studi funzionali che si rivelano indispensabili per poter definire l’effetto delle varianti sul complesso GPIb-IX-V. Nell’ambito invece dello studio e caratterizzazione della forma meno grave di BSS (BSSA2) sono stati selezionati 120 pazienti piastrinopenici senza diagnosi caratterizzati da piastrine grandi. In questi pazienti sono stati analizzati i geni GP1BA, GP1BB e GP9 e sono state identificate 11 diverse varianti: 1 nonsense, 2 mutazioni di framshift, 1 mutazione nel codone di inizio e 5 varianti missense. Gli studi funzionali eseguiti sulle varianti missense per stabilire il loro ruolo patogenetico sono ancora in corso. Tuttavia se gli studi dovessero confermare la loro patogenicità 11 pazienti su 120 risulterebbero BSSA2 e questa forma dovrebbe essere considerata una tra le piastrinopenie ereditarie più frequenti in Italia. In conclusione grazie a questo studio è stato possibile raccogliere la più ampia casistica di pazienti affetti da BSSA1 fin’ora descritta e ottenere numerose informazioni sia sulla clinica che sulle mutazioni coinvolte. Il BSS Consortium database permetterà ai clinici che hanno partecipato allo studio di osservare nel tempo l’andamento della malattia nei pazienti e di ottenere informazioni utili per stabilire un corretto protocollo per la presa in carico dei pazienti. Infine la caratterizzazione di nuove forme di BSSA2 rappresenta il punto di partenza per descrivere al meglio la malattia BSSA2 sia dal punto di vista clinico che molecolare. In futuro sarà quindi indispensabile estendere il BSS Consortium database anche alla forma BSSA2. XXVII Ciclo XXVII Ciclo 1979

Fanconi Anemia (FA) is a cancer predisposition syndrome with cells sensitivity to interstrand crosslinking (ICL) agents such as cisplatin (CDDP). Genes in the FA pathway are evolutionary conserved, allowing genetic and molecular studies in the model system C.elegans. The FA pathway is involved in the choice between the high fidelity repair pathway, Homologous Repair (HR), and the error prone Non-Homologous End Joining (NHEJ). In C. elegans FCD-2 (the orthologue of the human FACD2) suppresses the use of NHEJ pathway and prevents DNA repair defects (Adamo et al. 2010). In order to confirm this data and determine the effect of the NHEJ block, ICL sensitivity assays were performed in FA patients' cell lines harbouring mutations in FANCC (ADLAT) and treated with siRNA against different components of NHEJ pathway. Preliminary data suggest that the inhibition of KU80 decreases the ICL sensitivity partially restoring the wild type phenotype. clt-2 (cross-linking-tolerance) is a spontaneous recessive mutation we identified in a fcd-2 background for its ability to suppress the CDDP hyper-sensitivity of fcd-2. The average number of meiotic RAD-51 foci and apoptotic nuclei in untreated worms decreases in the clt-2;fcd-2 compared to fcd-2 excluding the possibility that clt-2 is implicated in CDDP uptake. clt-2 mutation significantly reduces the percentage of developmental defects occurring in the fcd-2 population. In our previous studies the same phenomenon was observed in absence of functional NHEJ in lig-4;fcd-2. However, no mutations in known genes of the NHEJ pathways were observed in clt-2. Furthermore, unlike in fcd-2;lig-4 and lig-4 mutants, where the NHEJ is defective, in the clt-2;fcd-2 and fcd-2 mutants the NHEJ works at levels similar to the wild-type in late embryogenesis. Unlike in fcd-2 strains, however, no up-level of NHEJ was observed during meiosis in the clt-2;fcd-2. The mutation has genetically been mapped on chromosome II and genomic sequencing has restricted the region to 800 Mb by linkage mapping. To identify novel players in ICL repair pathway choice we have undertaken a parallel biochemical and proteomic approach. We have obtained an antibody directed against the C-terminal domain of the C. elegans FCD-2 protein. The antibody recognizes both the endogenous and the heterologously expressed protein in its native as well as denatured forms and thus is suitable to the identification of FCD-2 interacting partners. To study the expression and regulation of these proteins we have set up proteomic analysis methods in C. elegans for differentially expressed proteins in response to ICL damage. Recombinant forms of the full-length FCD-2 and its interacting partner FANC-I proteins have been expressed in E. coli, along with a collection of deletion mutants encoding different domains of both proteins. The study of the biochemical activities of these proteins and their interactions by in vitro qualitative and quantitative assays is underway.