Risk and fate of residual interatrial shunting after transcatheter closure of patent foramen ovale: a long term follow up study

<p>Abstract</p> <p>Background</p> <p>Percutaneous transcatheter closure of patent foramen ovale (PFO) in cryptogenic stroke is an alternative to medical therapy. There is still debate on different outcome for each currently available device. The impact of residual shunting after PFO-clo- sure on recurrent arterial embolism is unknown.</p> <p>Aims</p> <p>(i) To evaluate the prevalence of residual interatrial shunting after device- closure of PFO, (ii) to identify risk factors predicting residual interatrial shunting after device implantation, and (iii) to investigate the outcome of patients after PFO-closure during long- term follow- up (FU).</p> <p>Methods and results</p> <p>Between 2000- 2005 PFO-closure was performed in 124 patients using four different devices: Amplatzer PFO-(n = 52), CardioSeal (n = 33), Helex (n = 23) and Premere (n = 16) occluder. All patients underwent serial contrast-enhanced transesophageal echocardiography (TEE) for 24 months after PFO- closure; clinical FU was at minimum 5 years up to 9.75 years (mean 6.67 ± 1.31 years). Overall-closure rate was 87% at 2 years, device-specific closure time curves differed significantly (p-logrank = 0.003). Independent risk factors for residual-shunting were implantation of a Helex occluder (hazard ratio [HR] 12.6, 95% confidence interval [CI] 2.6- 57.4, p = 0.002), PFO- canal- lengths (HR 1.2, 95%CI 1.1- 1.3, p = 0.004) and extend of atrial-septal-aneurysm (HR 1.1, 95%CI 0.9- 1.3; p = 0.05). 4 (3.2%) arterial embolic events occurred during a FU-period of 817.2 patient-years, actuarial annual thromboembolic-risk was 0.49%. All ischemic events were not related to residual PFO-shunting or device-related thrombus- formation.</p> <p>Conclusion</p> <p>Success rates of PFO- closure are mainly dependent on occluder-type, extend of concomitant atrial-septum-aneurysm and PFO-canal- length. Importantly, residual shunting after PFO-closure was not associated with recurrence of arterial embolism during long-term follow-up.</p

POLITICHE DI AMMISSIONE E GESTIONE DEI FLUSSI MIGRATORI DA LAVORO IN ITALIA DALLA TURCO-NAPOLITANO AD OGGI.

L'obiettivo di questo elaborato è quello di analizzare gli strumenti di cui si è dotata l'Italia al fine di regolare i flussi immigratori da lavoro. Dall'analisi svolta emerge la difficoltà dei governi italiani ad abbandonare una gestione emergenziale e contingente del fenomeno in favore di una maggiore consapevolezza di fronte all'immigrazione, in generale, e quella economica in particolare, in quanto elemento strutturale del tessuto socio-economico italiano. Le difficoltà oggettive, incontrate nella stesura dell'elaborato, sono frutto della complessità del fenomeno di per sé di natura transnazionale e che coinvolge una moltitudine di soggetti, oltre a presentare molteplici aspetti, da quelli socio-economici a quelli prettamente politici, fortemente intrecciati tra loro. Data la complessità di questo versante della politica migratoria, ho scelto una chiave di lettura storica, in quanto permette di evidenziare il profondo legame tra la discussione politica, caratterizzata da una forte polarizzazione ideologica, e gli interventi attuati in questa materia. All'interno di questi equilibri s'inserisce, inoltre, il crescente ruolo dell'Unione Europea che chiede, nonostante le resistenze dei singoli Stati, di rinunciare a una porzione di sovranità col fine di creare una politica migratoria comune. Nel primo capitolo vengono analizzati l'origine del fenomeno e la nascita della politica migratoria in Italia. Con l'approvazione della legge Turco-Napolitano nel 1998, e il conseguente raggruppamento delle leggi all'interno del Testo Unico, l'Italia cerca di dotarsi di una legge organica in materia migratoria. Il sistema è incentrato sulla chiamata nominativa del lavoratore ancora all'estero, che avviene secondo i limiti numerici definiti dalla programmazione dei flussi ed attuati attraverso il cosiddetto decreto-flussi. Questo meccanismo dimostra, fin dalla nascita, notevoli inadeguatezze e carenze, per cui si deve ricorrere sistematicamente a strumenti di regolarizzazione ex post di una presenza irregolare che tende a riprodursi, anche a causa del lavoro sommerso che funge da potente fattore d'attrazione dei flussi, e tutto questo perché, sia i datori di lavoro che i lavoratori immigrati, non trovano conveniente utilizzare i canali d'ingresso regolari. Nel secondo capitolo il punto di partenza è rappresentato dalla riforma attuata dalla legge Bossi-Fini nel 2001. Tale legge è frutto della nuova maggioranza di centro-destra che fa dell'immigrazione un tema cruciale per raccogliere consensi, associandola a situazioni problematiche di sicurezza e ordine pubblico. La legge interviene in maniera sostanziale sui meccanismi di ammissione, inasprendo le condizioni di ingresso con l'introduzione del “contratto di soggiorno” (che subordina la presenza alla disponibilità di un'occupazione lavorativa) e precarizzando il soggiorno dei regolari, dimezzando la durata dei permessi. Ai fattori interni si aggiunge l'influenza dell'Unione Europea. L'allargamento verso i paesi dell'Est rappresenta l'apice delle carenze del meccanismo di ammissione: una larga parte degli ingressi si sottrae al potere regolatorio del sistema delle quote, dal momento che buona parte dei flussi si compone di soggetti che non necessitano più di alcun permesso di soggiorno. La medesima incapacità emerge anche con il presentarsi della crisi economica alla fine del 2008. Infatti, nonostante la drastica riduzione delle quote, i flussi, prevalentemente diretti al servizio alle famiglie, si mantengono elevati e subiscono una battuta d'arresto solo a partire dal 2011. Nel terzo capitolo vengono presi in considerazione i provvedimenti più recenti: l'Accordo d'Integrazione all'interno del Piano per l'Integrazione e la Carta Blu sono frutto del crescente ruolo dell'Unione Europea e dell'affermarsi del nuovo (e più impegnativo) concetto d'integrazione e, pertanto, rappresentano il tentativo dell'azione politica di adeguarsi ai principi della politica migratoria dell'Unione Europea. Tali provvedimenti, tuttavia, hanno suscitato perplessità e critiche, sia in termini ideologici che in termini di attuabilità concreta, data la mancata predisposizione di risorse aggiuntive necessarie. Il quadro che emerge è che l'Italia ha attratto ingenti flussi senza che a questi corrispondesse una crescita economica, e questo è frutto del potere d'attrazione costituito dai fattori socio-demografici, come la bassa natalità, l'invecchiamento della popolazione, l'evoluzione delle aspettative lavorative, soprattutto dei giovani. In conclusione i problemi rimangono aperti, anche se oggi meno visibili principalmente per due fattori. Il primo consiste nella mancanza di un dibattito politico e mediatico, nonché scientifico, causato dalla poca notiziabilità dell'immigrazione regolare, in favore degli aspetti più eclatanti e conflittuali. Il secondo invece è rappresentato dalla battuta d'arresto dei flussi di arrivo, che fa apparire il problema lontano. E così l'azione politica aspetta, finché non si presenterà la prossima emergenza

A quantitative PCR method to quantify ruminant DNA in porcine crude heparin

Heparin is a well-known glycosaminoglycan extracted from porcine intestines. Increased vigilance for transmissible spongiform encephalopathy in animal-derived pharmaceuticals requires methods to prevent the introduction of heparin from ruminants into the supply chain. The sensitivity, specificity, and precision of the quantitative polymerase chain reaction (PCR) make it a superior analytical platform for screening heparin raw material for bovine-, ovine-, and caprine-derived material. A quantitative PCR probe and primer set homologous to the ruminant Bov-A2 short interspersed nuclear element (SINE) locus (Mendoza-Romero et al. J. Food Prot. 67:550–554, 2004) demonstrated nearly equivalent affinities for bovine, ovine, and caprine DNA targets, while exhibiting no cross-reactivity with porcine DNA in the quantitative PCR method. A second PCR primer and probe set, specific for the porcine PRE1 SINE sequence, was also developed to quantify the background porcine DNA level. DNA extraction and purification was not necessary for analysis of the raw heparin samples, although digestion of the sample with heparinase was employed. The method exhibits a quantitation range of 0.3–3,000 ppm ruminant DNA in heparin. Validation parameters of the method included accuracy, repeatability, precision, specificity, range, quantitation limit, and linearity

Kinome rewiring reveals AURKA limits PI3K-pathway inhibitor efficacy in breast cancer.

Dysregulation of the PI3K-AKT-mTOR signaling network is a prominent feature of breast cancers. However, clinical responses to drugs targeting this pathway have been modest, possibly because of dynamic changes in cellular signaling that drive resistance and limit drug efficacy. Using a quantitative chemoproteomics approach, we mapped kinome dynamics in response to inhibitors of this pathway and identified signaling changes that correlate with drug sensitivity. Maintenance of AURKA after drug treatment was associated with resistance in breast cancer models. Incomplete inhibition of AURKA was a common source of therapy failure, and combinations of PI3K, AKT or mTOR inhibitors with the AURKA inhibitor MLN8237 were highly synergistic and durably suppressed mTOR signaling, resulting in apoptosis and tumor regression in vivo. This signaling map identifies survival factors whose presence limits the efficacy of targeted therapies and reveals new drug combinations that may unlock the full potential of PI3K-AKT-mTOR pathway inhibitors in breast cancer

Ca2+/Calmodulin-Dependent Protein Kinase Kinase Is Not Involved in Hypothalamic AMP-Activated Protein Kinase Activation by Neuroglucopenia

Hypoglycemia and neuroglucopenia stimulate AMP-activated protein kinase (AMPK) activity in the hypothalamus and this plays an important role in the counterregulatory responses, i.e. increased food intake and secretion of glucagon, corticosterone and catecholamines. Several upstream kinases that activate AMPK have been identified including Ca2+/Calmodulin-dependent protein kinase kinase (CaMKK), which is highly expressed in neurons. However, the involvement of CaMKK in neuroglucopenia-induced activation of AMPK in the hypothalamus has not been tested. To determine whether neuroglucopenia-induced AMPK activation is mediated by CaMKK, we tested whether STO-609 (STO), a CaMKK inhibitor, would block the effects of 2-deoxy-D-glucose (2DG)-induced neuroglucopenia both ex vivo on brain sections and in vivo. Preincubation of rat brain sections with STO blocked KCl-induced α1 and α2-AMPK activation but did not affect AMPK activation by 2DG in the medio-basal hypothalamus. To confirm these findings in vivo, STO was pre-administrated intracerebroventricularly (ICV) in rats 30 min before 2DG ICV injection (40 µmol) to induce neuroglucopenia. 2DG-induced neuroglucopenia lead to a significant increase in glycemia and food intake compared to saline-injected control rats. ICV pre-administration of STO (5, 20 or 50 nmol) did not affect 2DG-induced hyperglycemia and food intake. Importantly, activation of hypothalamic α1 and α2-AMPK by 2DG was not affected by ICV pre-administration of STO. In conclusion, activation of hypothalamic AMPK by 2DG-induced neuroglucopenia is not mediated by CaMKK

Defining the genetic control of human blood plasma N-glycome using genome-wide association study

Glycosylation is a common post-translational modification of proteins. Glycosylation is associated with a number of human diseases. Defining genetic factors altering glycosylation may provide a basis for novel approaches to diagnostic and pharmaceutical applications. Here we report a genome-wide association study of the human blood plasma N-glycome composition in up to 3811 people measured by Ultra Performance Liquid Chromatography (UPLC) technology. Starting with the 36 original traits measured by UPLC, we computed an additional 77 derived traits leading to a total of 113 glycan traits. We studied associations between these traits and genetic polymorphisms located on human autosomes. We discovered and replicated 12 loci. This allowed us to demonstrate an overlap in genetic control between total plasma protein and IgG glycosylation. The majority of revealed loci contained genes that encode enzymes directly involved in glycosylation (FUT3/FUT6, FUT8, B3GAT1, ST6GAL1, B4GALT1, ST3GAL4, MGAT3 and MGAT5) and a known regulator of plasma protein fucosylation (HNF1A). However, we also found loci that could possibly reflect other more complex aspects of glycosylation process. Functional genomic annotation suggested the role of several genes including DERL3, CHCHD10, TMEM121, IGH and IKZF1. The hypotheses we generated may serve as a starting point for further functional studies in this research area

Repair at Single Targeted DNA Double-Strand Breaks in Pluripotent and Differentiated Human Cells

Differences in ex vivo cell culture conditions can drastically affect stem cell physiology. We sought to establish an assay for measuring the effects of chemical, environmental, and genetic manipulations on the precision of repair at a single DNA double-strand break (DSB) in pluripotent and somatic human cells. DSBs in mammalian cells are primarily repaired by either homologous recombination (HR) or nonhomologous end-joining (NHEJ). For the most part, previous studies of DSB repair in human cells have utilized nonspecific clastogens like ionizing radiation, which are highly nonphysiologic, or assayed repair at randomly integrated reporters. Measuring repair after random integration is potentially confounded by locus-specific effects on the efficiency and precision of repair. We show that the frequency of HR at a single DSB differs up to 20-fold between otherwise isogenic human embryonic stem cells (hESCs) based on the site of the DSB within the genome. To overcome locus-specific effects on DSB repair, we used zinc finger nucleases to efficiently target a DSB repair reporter to a safe-harbor locus in hESCs and a panel of somatic human cell lines. We demonstrate that repair at a targeted DSB is highly precise in hESCs, compared to either the somatic human cells or murine embryonic stem cells. Differentiation of hESCs harboring the targeted reporter into astrocytes reduces both the efficiency and precision of repair. Thus, the phenotype of repair at a single DSB can differ based on either the site of damage within the genome or the stage of cellular differentiation. Our approach to single DSB analysis has broad utility for defining the effects of genetic and environmental modifications on repair precision in pluripotent cells and their differentiated progeny

The mutational impact of culturing human pluripotent and adult stem cells

Genetic changes acquired during in vitro culture pose a risk for the successful application of stem cells in regenerative medicine. To assess the genetic risks induced by culturing, we determined all mutations in individual human stem cells by whole genome sequencing. Individual pluripotent, intestinal, and liver stem cells accumulate 3.5 ± 0.5, 7.2 ± 1.1 and 8.3 ± 3.6 base substitutions per population doubling, respectively. The annual in vitro mutation accumulation rate of adult stem cells is nearly 40-fold higher than the in vivo mutation accumulation rate. Mutational signature analysis reveals that in vitro induced mutations are caused by oxidative stress. Reducing oxygen tension in culture lowers the mutational load. We use the mutation rates, spectra, and genomic distribution to model the accumulation of oncogenic mutations during typical in vitro expansion, manipulation or screening experiments using human stem cells. Our study provides empirically defined parameters to assess the mutational risk of stem cell based therapies

DNA Repair in Human Pluripotent Stem Cells Is Distinct from That in Non-Pluripotent Human Cells

The potential for human disease treatment using human pluripotent stem cells, including embryonic stem cells and induced pluripotent stem cells (iPSCs), also carries the risk of added genomic instability. Genomic instability is most often linked to DNA repair deficiencies, which indicates that screening/characterization of possible repair deficiencies in pluripotent human stem cells should be a necessary step prior to their clinical and research use. In this study, a comparison of DNA repair pathways in pluripotent cells, as compared to those in non-pluripotent cells, demonstrated that DNA repair capacities of pluripotent cell lines were more heterogeneous than those of differentiated lines examined and were generally greater. Although pluripotent cells had high DNA repair capacities for nucleotide excision repair, we show that ultraviolet radiation at low fluxes induced an apoptotic response in these cells, while differentiated cells lacked response to this stimulus, and note that pluripotent cells had a similar apoptotic response to alkylating agent damage. This sensitivity of pluripotent cells to damage is notable since viable pluripotent cells exhibit less ultraviolet light-induced DNA damage than do differentiated cells that receive the same flux. In addition, the importance of screening pluripotent cells for DNA repair defects was highlighted by an iPSC line that demonstrated a normal spectral karyotype, but showed both microsatellite instability and reduced DNA repair capacities in three out of four DNA repair pathways examined. Together, these results demonstrate a need to evaluate DNA repair capacities in pluripotent cell lines, in order to characterize their genomic stability, prior to their pre-clinical and clinical use

Post-translational regulation contributes to the loss of LKB1 expression through SIRT1 deacetylase in osteosarcomas

background: The most prevalent form of bone cancer is osteosarcoma (OS), which is associated with poor prognosis in case of metastases formation. Mice harbouring liver kinase B1 (LKB1+/−) develop osteoblastoma-like tumours. Therefore, we asked whether loss of LKB1 gene has a role in the pathogenesis of human OS. methods: Osteosarcomas (n=259) were screened for LKB1 and sirtuin 1 (SIRT1) protein expression using immunohistochemistry and western blot. Those cases were also screened for LKB1 genetic alterations by next-generation sequencing, Sanger sequencing, restriction fragment length polymorphism and fluorescence in situ hybridisation approaches. We studied LKB1 protein degradation through SIRT1 expression. MicroRNA expression investigations were also conducted to identify the microRNAs involved in the SIRT1/LKB1 pathway. results: Forty-one per cent (106 out of 259) OS had lost LKB1 protein expression with no evident genetic anomalies. We obtained evidence that SIRT1 impairs LKB1 protein stability, and that SIRT1 depletion leads to accumulation of LKB1 in OS cell lines resulting in growth arrest. Further investigations revealed the role of miR-204 in the regulation of SIRT1 expression, which impairs LKB1 stability. conclusions: We demonstrated the involvement of sequential regulation of miR-204/SIRT1/LKB1 in OS cases and showed a mechanism for the loss of expression of LKB1 tumour suppressor in this malignancy