PDE2A is indispensable for mouse liver development and hematopoiesis

Phosphodiesterase 2A (PDE2A) is a cAMP-cGMP hydrolyzing enzyme essential for mouse development and the PDE2A knockout model (PDE2A−/−) is embryonic lethal. Notably, livers of PDE2A−/− embryos at embryonic day 14.5 (E14.5) have extremely reduced size. Morphological, cellular and molecular analyses revealed loss of integrity in the PDE2A−/− liver niche that compromises the hematopoietic function and maturation. Hematopoietic cells isolated from PDE2A−/− livers are instead able to differentiate in in vitro assays, suggesting the absence of blood cell-autonomous defects. Apoptosis was revealed in hepatoblasts and at the endothelial and stromal compartments in livers of PDE2A−/− embryos. The increase of the intracellular cAMP level and of the inducible cAMP early repressor (ICER) in liver of PDE2A−/− embryos might explain the impairment of liver development by downregulating the expression of the anti-apoptotic gene Bcl2. In summary, we propose PDE2A as an essential gene for integrity maintenance of liver niche and the accomplishment of hematopoiesis

Connexin Hemichannel Activation by S-Nitrosoglutathione Synergizes Strongly with Photodynamic Therapy Potentiating Anti-Tumor Bystander Killing

In this study, we used B16-F10 cells grown in the dorsal skinfold chamber (DSC) preparation that allowed us to gain optical access to the processes triggered by photodynamic therapy (PDT). Partial irradiation of a photosensitized melanoma triggered cell death in non-irradiated tumor cells. Multiphoton intravital microscopy with genetically encoded fluorescence indicators revealed that bystander cell death was mediated by paracrine signaling due to adenosine triphosphate (ATP) release from connexin (Cx) hemichannels (HCs). Intercellular calcium (Ca2+) waves propagated from irradiated to bystander cells promoting intracellular Ca2+ transfer from the endoplasmic reticulum (ER) to mitochondria and rapid activation of apoptotic pathways. Combination treatment with S-nitrosoglutathione (GSNO), an endogenous nitric oxide (NO) donor that biases HCs towards the open state, greatly potentiated anti-tumor bystander killing via enhanced Ca2+ signaling, leading to a significant reduction of post-irradiation tumor mass. Our results demonstrate that HCs can be exploited to dramatically increase cytotoxic bystander effects and reveal a previously unappreciated role for HCs in tumor eradication promoted by PDT

A large scale hearing loss screen reveals an extensive unexplored genetic landscape for auditory dysfunction

The developmental and physiological complexity of the auditory system is likely reflected in the underlying set of genes involved in auditory function. In humans, over 150 non-syndromic loci have been identified, and there are more than 400 human genetic syndromes with a hearing loss component. Over 100 non-syndromic hearing loss genes have been identified in mouse and human, but we remain ignorant of the full extent of the genetic landscape involved in auditory dysfunction. As part of the International Mouse Phenotyping Consortium, we undertook a hearing loss screen in a cohort of 3006 mouse knockout strains. In total, we identify 67 candidate hearing loss genes. We detect known hearing loss genes, but the vast majority, 52, of the candidate genes were novel. Our analysis reveals a large and unexplored genetic landscape involved with auditory function

Il resveratrolo agisce come agonista dell'acido retinoico per il recettore RAR (gamma( inibendo il differenziamento dei cheratinociti umani in coltura

Dottorato di ricerca in biologia e fisiopatologia degli epiteli. 12. Ciclo. A.a. 1996-99. Docente guida e coordinatore A. Finazzi Agro'Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Pain coping strategies in paediatric patients newly diagnosed with leukaemia compared with healthy peers

Objective: Children with leukaemia experience special difficulties adapting to stressful medical procedures and to the adverse effects of chemotherapy, though they can implement their coping strategies. The aims of the study were to assess whether the coping-with-pain strategies could be influenced by a child's personal and illness factors and to render possible comparisons between children with leukaemia and healthy peers. Another aim was to compare parents' and children's reports on coping strategies. Methods: A total of 125 patients (average age = 6.79 years; SD = 3.40) with acute leukaemia (lymphocytic leukaemia 90.4% and myeloid leukaemia 9.6%) and agematched healthy children with their parents were enrolled in the study. A sociodemographic questionnaire and the Waldon–Varni Pediatric Pain Coping Inventory, parent and self-report versions, were administered 1 month after diagnosis. Data regarding the therapy's side effects were recorded. Results: The comparison between proxy-reports of the two groups of parents found significant differences in terms of social support, self-cognitive instructions and catastrophising strategies. Children aged 6–10 years relied more heavily on distraction than children of other ages, using more problem-solving and self-cognitive instructions. The results indicated moderate parent–child agreement. Conclusion: Health professionals could help paediatric leukaemic patients in adopting more efficiently pain coping strategies applicable for different ages

ATM kinase dead: from ataxia telangiectasia syndrome to cancer

ATM is one of the principal players of the DNA damage response. This protein exerts its role in DNA repair during cell cycle replication, oxidative stress, and DNA damage from endogenous events or exogenous agents. When is activated, ATM phosphorylates multiple substrates that participate in DNA repair, through its phosphoinositide 3-kinase like domain at the 3'end of the protein. The absence of ATM is the cause of a rare autosomal recessive disorder called Ataxia Telangiectasia characterized by cerebellar degeneration, telangiectasia, immunodeficiency, cancer susceptibility, and radiation sensitivity. There is a correlation between the severity of the phenotype and the mutations, depending on the residual activity of the protein. The analysis of patient mutations and mouse models revealed that the presence of inactive ATM, named ATM kinase-dead, is more cancer prone and lethal than its absence. ATM mutations fall into the whole gene sequence, and it is very difficult to predict the resulting effects, except for some frequent mutations. In this regard, is necessary to characterize the mutated protein to assess if it is stable and maintains some residual kinase activity. Moreover, the whole-genome sequencing of cancer patients with somatic or germline mutations has highlighted a high percentage of ATM mutations in the phosphoinositide 3-kinase domain, mostly in cancer cells resistant to classical therapy. The relevant differences between the complete absence of ATM and the presence of the inactive form in in vitro and in vivo models need to be explored in more detail to predict cancer predisposition of A-T patients and to discover new therapies for ATM-associated cancer cells. In this review, we summarize the multiple discoveries from humans and mouse models on ATM mutations, focusing into the inactive versus null ATM

Psychological Wellbeing in Adolescents with Leukaemia: A Comparative Study with Typical Development Peers

There is still little research on psychological wellbeing, life satisfaction and reported problems in preadolescents and adolescents under therapy for leukaemia, and also little research comparing them with their healthy peers. The present study aimed to analyse the life satisfaction, hope, psychological wellbeing and reported problems’ intensity in 60 patients aged 8–18 during the first year of therapy, to identify those more at risk and to compare their reports with matched healthy peers. A battery of self-reported questionnaires was administered during hospitalisation or day hospital admissions post 6 months and post 12 months from the diagnosis. Younger patients (aged 8–13 years) were more at risk than older ones in their problems’ intensity and psychological symptoms; females and Acute Myeloid Leukaemia patients reported lower current life satisfaction perceptions; hope was associated with lower depression symptoms and mood problems. Healthy peers have a better perception of current life, but reported a lower hope score, more anxiety symptoms and more cognitive problems than patients. The first 6 months were more critical for patients’ psychological health. Basing on these empirical data, the inclusion of mental health care professionals or supportive psychotherapy into the treatment is recognized as extremely useful

The impact of five years storage/biobanking at -80°C on mouse spermatozoa fertility, physiology and function

We previously demonstrated how mouse spermatozoa can be efficiently stored for two years in a -80°C freezer, maintaining their ability to fertilize mouse eggs