Prognostic role of BNP in children undergoing surgery for congenital heart disease: analysis of prediction models incorporating standard risk factors.

BACKGROUND: The routine use of brain natriuretic peptide (BNP) in pediatric cardiac surgery remains controversial. Our aim was to test whether BNP adds information to predict risk in pediatric cardiac surgery. METHODS: In all, 587 children undergoing cardiac surgery (median age 6.3 months; 1.2-35.9 months) were prospectively enrolled at a single institution. BNP was measured pre-operatively, on every post-operative day in the intensive care unit, and before discharge. The primary outcome was major complications and length ventilator stay \u3e15 days. A first risk prediction model was fitted using Cox proportional hazards model with age, body surface area and Aristotle score as continuous predictors. A second model was built adding cardiopulmonary bypass time and arterial lactate at the end of operation to the first model. Then, peak post-operative log-BNP was added to both models. Analysis to test discrimination, calibration, and reclassification were performed. RESULTS: BNP increased after surgery (p CONCLUSIONS: Our data indicates that BNP may improve the risk prediction in pediatric cardiac surgery, supporting its routine use in this setting

A Neutralizing RNA Aptamer against EGFR Causes Selective Apoptotic Cell Death

Nucleic acid aptamers have been developed as high-affinity ligands that may act as antagonists of disease-associated proteins. Aptamers are non immunogenic and characterised by high specificity and low toxicity thus representing a valid alternative to antibodies or soluble ligand receptor traps/decoys to target specific cancer cell surface proteins in clinical diagnosis and therapy. The epidermal growth factor receptor (EGFR) has been implicated in the development of a wide range of human cancers including breast, glioma and lung. The observation that its inhibition can interfere with the growth of such tumors has led to the design of new drugs including monoclonal antibodies and tyrosine kinase inhibitors currently used in clinic. However, some of these molecules can result in toxicity and acquired resistance, hence the need to develop novel kinds of EGFR-targeting drugs with high specificity and low toxicity. Here we generated, by a cell-Systematic Evolution of Ligands by EXponential enrichment (SELEX) approach, a nuclease resistant RNA-aptamer that specifically binds to EGFR with a binding constant of 10 nM. When applied to EGFR-expressing cancer cells the aptamer inhibits EGFR-mediated signal pathways causing selective cell death. Furthermore, at low doses it induces apoptosis even of cells that are resistant to the most frequently used EGFR-inhibitors, such as gefitinib and cetuximab, and inhibits tumor growth in a mouse xenograft model of human non-small-cell lung cancer (NSCLC). Interestingly, combined treatment with cetuximab and the aptamer shows clear synergy in inducing apoptosis in vitro and in vivo. In conclusion, we demonstrate that this neutralizing RNA-aptamer is a promising bio-molecule that can be developed as a more effective alternative to the repertoire of already existing EGFR-inhibitors

Role of Pax8 transcriptional factor in the differentiated thyroid

In Pax8-/- mice the thyroid anlage disappears around E11.5. At birth the gland appears as a rudimentary structure composed only of C cells while thyroid follicular cells are undetectable. Thus, this model does not allow the study of Pax8 function in the postnatal thyroid. To address the role of Pax8 in the differentiated thyroid, I established novel strains amenable to thyroid follicular cell-specific conditional knockout of Pax8 gene using the Cre/lox system. A genetically modified mouse strain (Pax8fl/fl) harbouring a floxed allele of Pax8 was generated. These mice were crossed with two different Cre mice, a Pax8Cre/+ strain expressing constitutively Cre recombinase by embryonic day 8.5 and a Tg-CreER strain in which Cre is active in thyroid follicular cells following tamoxifen injection. Pax8Cre/fl mice do not display an overt phenotype during embryonic life. However, 3-week old Pax8Cre/fl pups show a hypothyroid phenotype characterized by both an increased serum TSH value and a significant reduction in body weight when compared with their wild type littermates. In Pax8Cre/fl animals the thyroid gland is hypoplastic and shows the absence of the follicular structure; moreover, the expression of many thyroid specific genes, required for both hormone production and regulative functions, is completely abolished. In addition, survival of follicular cells is impaired. The disruption of Pax8 in adult life (Pax8ko/fl;Tg-CreER strain) seems to be not efficient and thyroid structure appears comparable to that of wild type. However, the absence of a clear phenotype in the Pax8ko/fl;TgCreER thyroid could be due to the compensatory proliferation of cells in which Pax8 has not been inactivated. In conclusion, in my thesis work I demonstrated in vivo that Pax8 plays a key role in controlling both the expression of many thyroid specific genes and the survival of thyroid follicular cells

De novo transcriptome assembly of a lipoxygenase knock-down strain in the diatom Pseudo-nitzschia arenysensis

<p>We generated knock-down mutants for the LOX gene of the diatom <i>Pseudo-nitzschia arenysensis</i> to alter the synthesis of oxylipins and functionally investigate the mechanism of action of these metabolites in diatoms. Here, we present the functional classification of the transcript sequences obtained from the <i>de novo</i> assembly of RNA-seq data obtained both from the silenced and wild-type <i>P. arenysensis </i>strains. </p&gt

De novo transcriptome assembly of a lipoxygenase knock-down strain in the diatom Pseudo-nitzschia arenysensis

<p>We generated knock-down mutants for the LOX gene of the diatom <i>Pseudo-nitzschia arenysensis</i> to alter the synthesis of oxylipins and functionally investigate the mechanism of action of these metabolites in diatoms. Here, we present the  <i>de novo</i> assembly of RNA-seq data obtained both from the silenced and wild-type <i>P. arenysensis </i>strains and the related functional classification of the transcript sequences. </p&gt

The Ascidia Ciona robusta Provides Novel Insights on the Evolution of the AP-1 Transcriptional Complex

The Activator Protein-1 transcription factor family (AP-1) transcriptional complex is historically defined as an early response group of transcription factors formed by dimeric complexes of the Jun, Fos, Atf, and Maf bZIP proteins that control cell proliferation and differentiation by regulating gene expression. It has been greatly investigated in many model organisms across metazoan evolution. Nevertheless, its complexity and variability of action made its multiple functions difficult to be defined. Here, we place the foundations for understanding the complexity of AP-1 transcriptional members in tunicates. We investigated the gene members of this family in the ascidian Ciona robusta and identified single copies of Jun, Fos, Atf3, Atf2/7, and Maf bZIP-related factors that could have a role in the formation of the AP-1 complex. We highlight that mesenchyme is a common cellular population where all these factors are expressed during embryonic development, and that, moreover, Fos shows a wider pattern of expression including also notochord and neural cells. By ectopic expression in transgenic embryos of Jun and Fos genes alone or in combination, we investigated the phenotypic alterations induced by these factors and highlighted a degree of functional conservation of the AP-1 complex between Ciona and vertebrates. The lack of gene redundancy and the first pieces of evidence of conserved functions in the control of cell movements and structural organization exerted by these factors open the way for using Ciona as a helpful model system to uncover the multiple potentialities of this highly complex family of bZIP transcription factors

Molecular basis of functional myogenic specification of Bona Fide multipotent adult cardiac stem cells

Ischemic Heart Disease (IHD) remains the developed world's number one killer. The improved survival from Acute Myocardial Infarction (AMI) and the progressive aging of western population brought to an increased incidence of chronic Heart Failure (HF), which assumed epidemic proportions nowadays. Except for heart transplantation, all treatments for HF should be considered palliative because none of the current therapies can reverse myocardial degeneration responsible for HF syndrome. To stop the HF epidemic will ultimately require protocols to reduce the progressive cardiomyocyte (CM) loss and to foster their regeneration. It is now generally accepted that mammalian CMs renew throughout life. However, this endogenous regenerative reservoir is insufficient to repair the extensive damage produced by AMI/IHD while the source and degree of CM turnover remains strongly disputed. Independent groups have convincingly shown that the adult myocardium harbors bona-fide tissue specific cardiac stem cells (CSCs). Unfortunately, recent reports have challenged the identity and the endogenous myogenic capacity of the c-kit expressing CSCs. This has hampered progress and unless this conflict is settled, clinical tests of repair/regenerative protocols are unlikely to provide convincing answers about their clinical potential. Here we review recent data that have eventually clarified the specific phenotypic identity of true multipotent CSCs. These cells when coaxed by embryonic cardiac morphogens undergo a precisely orchestrated myogenic commitment process robustly generating bona-fide functional cardiomyocytes. These data should set the path for the revival of further investigation untangling the regenerative biology of adult CSCs to harness their potential for HF prevention and treatment

Mate Perception and Gene Networks Regulating the Early Phase of Sex in Pseudo-nitzschia multistriata

Diatoms are photosynthetic microorganisms playing a key role in the functioning of aquatic ecosystems; they are at the base of the food web and are the main drivers of biogeochemical processes. These microalgae have a unique diplontic life cycle in which the vegetative phase entails a cell size reduction that would lead to the extinction of the cell population if the size was not restored, usually by sexual reproduction. The switch from asexual to sexual reproduction needs to be finely synchronized and regulated to ensure its success; to this aim, cells evolved complex chemical crosstalk that mediates mating. We focused our attention on the marine diatom Pseudo-nitzschia multistriata, investigating the reciprocal perception of the opposite mating type (MT) and the genes and signaling molecules putatively involved in the process. From previously available transcriptomic data, we selected a panel of genes deregulated during the early phase of sexual reproduction, confirming for some of them a role during mate perception and establishing a hierarchy governing their behavior. Moreover, we explored the nature of the molecules controlling sexual reproduction in this species, unveiling that the signaling is mediated by the secretion of protein and non-protein cues from the MT− and MT+, respectively. Our results point to a model in which the two MTs stimulate each other, but the stimulation by the MT− is amplified after MT+ perception in a positive feedback manner