Antisense-mediated exon skipping: a therapeutic strategy for titin-based dilated cardiomyopathy

Frameshift mutations in the TTN gene encoding titin are a major cause for inherited forms of dilated cardiomyopathy (DCM), a heart disease characterized by ventricular dilatation, systolic dysfunction, and progressive heart failure. To date, there are no specific treatment options for DCM patients but heart transplantation. Here, we show the beneficial potential of reframing titin transcripts by antisense oligonucleotide (AON)-mediated exon skipping in human and murine models of DCM carrying a previously identified autosomal-dominant frameshift mutation in titin exon 326. Correction of TTN reading frame in patient-specific cardiomyocytes derived from induced pluripotent stem cells rescued defective myofibril assembly and stability and normalized the sarcomeric protein expression. AON treatment in Ttn knock-in mice improved sarcomere formation and contractile performance in homozygous embryos and prevented the development of the DCM phenotype in heterozygous animals. These results demonstrate that disruption of the titin reading frame due to a truncating DCM mutation canbe restored by exon skipping in both patient cardiomyocytes invitro and mouse heart invivo, indicating RNA-based strategies as a potential treatment option for DCM

Association of growth with neurodevelopment in extremely low gestational age infants: a population-based analysis

To assess the association between postnatal growth and neurodevelopment at the age of 2 years in extremely low gestational age newborns (ELGAN, < 28 weeks' gestation). Retrospective population-based cohort study including all live born ELGAN in 2006-2012 in Switzerland. Growth parameters (weight, length, head circumference, body mass index) were assessed at birth, at hospital discharge home, and 2-year follow-up (FU2). Unadjusted and adjusted regression models assessed associations between growth (birth to hospital discharge and birth to FU2) and neurodevelopment at FU2. A total of 1244 infants (mean GA 26.5 ± 1.0 weeks, birth weight 853 ± 189 g) survived to hospital discharge and were included in the analyses. FU2 was documented for 1049 (84.3%) infants. The mean (± SD) mental and a psychomotor development index at 2FU were 88.9 (± 18.0) and 86.9 (± 17.7), respectively. Moderate or severe neurodevelopmental impairment was documented in 23.2% of patients. Changes of z-scores between birth and discharge and between birth and FU2 for weight were - 1.06 (± 0.85) and - 0.140 (± 1.15), for length - 1.36 (± 1.34), and - 0.40 (± 1.33), for head circumference - 0.61 (± 1.04) and - 0.76 (± 1.32) as well as for BMI 0.22 (± 3.36) and - 0.006 (± 1.45). Unadjusted and adjusted analyses showed that none of the four growth parameters was significantly associated with any of the three outcome parameters of neurodevelopment. This was consistent for both time intervals. CONCLUSION In the present population-based cohort of ELGAN, neither growth between birth and hospital discharge nor between birth and FU2 were significantly associated with neurodevelopment at age of 2 years. WHAT IS KNOWN • Studies assessing the association between growth and neurodevelopment in extremely low gestational age newborns (28 weeks' gestation) show conflicting results. WHAT IS NEW • Neither growth between birth and hospital discharge nor between birth and corrected age of 2 years were significantly associated with neurodevelopment at age of 2 years. • The role of postnatal growth as a predictor of neurodevelopmental outcome during infancy might be smaller than previously assumed

Association of growth with neurodevelopment in extremely low gestational age infants: a population-based analysis.

To assess the association between postnatal growth and neurodevelopment at the age of 2 years in extremely low gestational age newborns (ELGAN, < 28 weeks' gestation). Retrospective population-based cohort study including all live born ELGAN in 2006-2012 in Switzerland. Growth parameters (weight, length, head circumference, body mass index) were assessed at birth, at hospital discharge home, and 2-year follow-up (FU2). Unadjusted and adjusted regression models assessed associations between growth (birth to hospital discharge and birth to FU2) and neurodevelopment at FU2. A total of 1244 infants (mean GA 26.5 ± 1.0 weeks, birth weight 853 ± 189 g) survived to hospital discharge and were included in the analyses. FU2 was documented for 1049 (84.3%) infants. The mean (± SD) mental and a psychomotor development index at 2FU were 88.9 (± 18.0) and 86.9 (± 17.7), respectively. Moderate or severe neurodevelopmental impairment was documented in 23.2% of patients. Changes of z-scores between birth and discharge and between birth and FU2 for weight were - 1.06 (± 0.85) and - 0.140 (± 1.15), for length - 1.36 (± 1.34), and - 0.40 (± 1.33), for head circumference - 0.61 (± 1.04) and - 0.76 (± 1.32) as well as for BMI 0.22 (± 3.36) and - 0.006 (± 1.45). Unadjusted and adjusted analyses showed that none of the four growth parameters was significantly associated with any of the three outcome parameters of neurodevelopment. This was consistent for both time intervals. CONCLUSION In the present population-based cohort of ELGAN, neither growth between birth and hospital discharge nor between birth and FU2 were significantly associated with neurodevelopment at age of 2 years. WHAT IS KNOWN • Studies assessing the association between growth and neurodevelopment in extremely low gestational age newborns (28 weeks' gestation) show conflicting results. WHAT IS NEW • Neither growth between birth and hospital discharge nor between birth and corrected age of 2 years were significantly associated with neurodevelopment at age of 2 years. • The role of postnatal growth as a predictor of neurodevelopmental outcome during infancy might be smaller than previously assumed

Is conditioning a useful framework for understanding the development and treatment of phobias?

Despite the prevalence of therapeutic interventions based on conditioning models of fear acquisition, conditioning has been seen by many as a poor explanation of how fears develop: partly because research on conditioning has become less mainstream and models of teaming have become increasingly more complex. This article reviews some of what is now known about conditioning/associative teaming and describes how these findings account for some early criticisms of conditioning models of fear acquisition. It also describes how pathways to fear such as vicarious teaming and fear information can be conceptualised as forms of associative teaming that obey the same teaming rules. Some popular models of conditioning are then described with a view to highlighting the important components in teaming. Finally, suggestions are made about how what we know about conditioning can be applied to improve therapeutic interventions and prevention programs for child anxiety. (c) 2006 Elsevier Ltd. All rights reserved

Haematopoietic cell transplantation in Switzerland, changes and results over 20 years: a report from the Swiss Blood Stem Cell Transplantation Working Group for Blood and Marrow Transplantation registry 1997-2016.

In 1997, the Swiss Blood Stem Cell Transplantation Group (SBST) initiated a mandatory national registry for all haematopoietic stem cell transplants (HCTs) in Switzerland. As of 2016, after 20 years, information was available for 7899 patients who had received an HCT (2781 allogeneic [35%] and 5118 autologous [65%]). As some patients had more than one transplant the total number of transplants was 3067 allogeneic and 6448 autologous. We compared patient characteristics and outcome of the first decade (1997-2006) and second decade (2007-2016) of the registry. There were numerous changes over time. For allogeneic HCT, transplant rates, and therefore use of HCT technology, increased from 14 to 21.8 HCTs per 1 million inhabitants per year from the first to the second decade. Likewise autologous HCTs increased from 24.8 to 37.2 annually corrected for population growth. Allogeneic transplant recipients were older (38.4 vs 48.3 years) and more frequently had unrelated donors in the second decade. Similarly, age increased for recipients of autologous HCT (50.8 vs 56.4 years). Analysis of outcome showed that the probabilities of overall and progression-free survival were stable over time, in spite of the treatment of older and higher risk patients. In multivariate analysis, nonrelapse mortality decreased in recipients of allogeneic HCT (relative risk 0.68, 95% confidence interval 0.52-0.87) over the two decades. Improvement in adjusted nonrelapse mortality compensated for the fact that higher risk patients were treated in more recent years, resulting in similar overall survival. Five-year survival probabilities were 56% (53-59%) in the first and 54% (51-57%) in the second decade for allogeneic HCT, and 59% (57-61%) in the first and 61% (59-63%) in the second decade for autologous HCT. Detailed analyses of changes over time are presented. This study included all HCTs performed in Switzerland during the period of observation and the data are useful for quality assurance programmes, healthcare cost estimation and healthcare planning. Between 50 and 60% of patients were long-term survivors after both types of HCT, indicating growing populations of surviving patients requiring long-term care and observation

Finding consistent disease subnetworks across microarray datasets

<p>Abstract</p> <p>Background</p> <p>While contemporary methods of microarray analysis are excellent tools for studying individual microarray datasets, they have a tendency to produce different results from different datasets of the same disease. We aim to solve this reproducibility problem by introducing a technique (SNet). SNet provides both quantitative and descriptive analysis of microarray datasets by identifying specific connected portions of pathways that are significant. We term such portions within pathways as “subnetworks”.</p> <p>Results</p> <p>We tested SNet on independent datasets of several diseases, including childhood ALL, DMD and lung cancer. For each of these diseases, we obtained two independent microarray datasets produced by distinct labs on distinct platforms. In each case, our technique consistently produced almost the same list of significant nontrivial subnetworks from two independent sets of microarray data. The gene-level agreement of these significant subnetworks was between 51.18% to 93.01%. In contrast, when the same pairs of microarray datasets were analysed using GSEA, t-test and SAM, this percentage fell between 2.38% to 28.90% for GSEA, 49.60% tp 73.01% for t-test, and 49.96% to 81.25% for SAM. Furthermore, the genes selected using these existing methods did not form subnetworks of substantial size. Thus it is more probable that the subnetworks selected by our technique can provide the researcher with more descriptive information on the portions of the pathway actually affected by the disease.</p> <p>Conclusions</p> <p>These results clearly demonstrate that our technique generates significant subnetworks and genes that are more consistent and reproducible across datasets compared to the other popular methods available (GSEA, t-test and SAM). The large size of subnetworks which we generate indicates that they are generally more biologically significant (less likely to be spurious). In addition, we have chosen two sample subnetworks and validated them with references from biological literature. This shows that our algorithm is capable of generating descriptive biologically conclusions.</p

A Systematic Analysis of the Clinical Outcome Associated with Multiple Reclassified Desmosomal Gene Variants in Arrhythmogenic Right Ventricular Cardiomyopathy Patients

The presence of multiple pathogenic variants in desmosomal genes (DSC2, DSG2, DSP, JUP, and PKP2) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) has been linked to a severe phenotype. However, the pathogenicity of variants is reclassified frequently, which may result in a changed clinical risk prediction. Here, we present the collection, reclassification, and clinical outcome correlation for the largest series of ARVC patients carrying multiple desmosomal pathogenic variants to date (n = 331). After reclassification, only 29% of patients remained carriers of two (likely) pathogenic variants. They reached the composite endpoint (ventricular arrhythmias, heart failure, and death) significantly earlier than patients with one or no remaining reclassified variant (hazard ratios of 1.9 and 1.8, respectively). Periodic reclassification of variants contributes to more accurate risk stratification and subsequent clinical management strategy. Graphical Abstract

Missense mutations in Desmocollin-2 N-terminus, associated with arrhythmogenic right ventricular cardiomyopathy, affect intracellular localization of desmocollin-2 in vitro

<p>Abstract</p> <p>Background</p> <p>Mutations in genes encoding desmosomal proteins have been reported to cause arrhythmogenic right ventricular cardiomyopathy (ARVC), an autosomal dominant disease characterised by progressive myocardial atrophy with fibro-fatty replacement.</p> <p>We screened 54 ARVC probands for mutations in desmocollin-2 (<it>DSC2</it>), the only desmocollin isoform expressed in cardiac tissue.</p> <p>Methods</p> <p>Mutation screening was performed by denaturing high-performance liquid chromatography and direct sequencing.</p> <p>To evaluate the pathogenic potentials of the <it>DSC2 </it>mutations detected in patients affected with ARVC, full-length wild-type and mutated cDNAs were cloned in eukaryotic expression vectors to obtain a fusion protein with green fluorescence protein (GFP); constructs were transfected in neonatal rat cardiomyocytes and in HL-1 cells.</p> <p>Results</p> <p>We identified two heterozygous mutations (c.304G>A (p.E102K) and c.1034T>C (p.I345T)) in two probands and in four family members. The two mutations p.E102K and p.I345T map to the N-terminal region, relevant to adhesive interactions.</p> <p>In vitro functional studies demonstrated that, unlike wild-type DSC2, the two N-terminal mutants are predominantly localised in the cytoplasm.</p> <p>Conclusion</p> <p>The two missense mutations in the N-terminal domain affect the normal localisation of DSC2, thus suggesting the potential pathogenic effect of the reported mutations. Identification of additional DSC2 mutations associated with ARVC may result in increased diagnostic accuracy with implications for genetic counseling.</p

A Systematic Analysis of the Clinical Outcome Associated with Multiple Reclassified Desmosomal Gene Variants in Arrhythmogenic Right Ventricular Cardiomyopathy Patients

The presence of multiple pathogenic variants in desmosomal genes (DSC2, DSG2, DSP, JUP, and PKP2) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) has been linked to a severe phenotype. However, the pathogenicity of variants is reclassified frequently, which may result in a changed clinical risk prediction. Here, we present the collection, reclassification, and clinical outcome correlation for the largest series of ARVC patients carrying multiple desmosomal pathogenic variants to date (n = 331). After reclassification, only 29% of patients remained carriers of two (likely) pathogenic variants. They reached the composite endpoint (ventricular arrhythmias, heart failure, and death) significantly earlier than patients with one or no remaining reclassified variant (hazard ratios of 1.9 and 1.8, respectively). Periodic reclassification of variants contributes to more accurate risk stratification and subsequent clinical management strategy. [Figure not available: see fulltext.]

Observing interactions between children and adolescents and their parents: the effects of anxiety disorder and age

Parental behaviors, most notably overcontrol, lack of warmth and expressed anxiety, have been implicated in models of the development and maintenance of anxiety disorders in children and young people. Theories of normative development have proposed that different parental responses are required to support emotional development in childhood and adolescence, yet age has not typically been taken into account in studies of parenting and anxiety disorders. In order to identify whether associations between anxiety disorder status and parenting differ in children and adolescents, we compared observed behaviors of parents of children (7–10 years) and adolescents (13–16 years) with and without anxiety disorders (n=120), while they undertook a series of mildly anxiety-provoking tasks. Parents of adolescents showed significantly lower levels of expressed anxiety, intrusiveness and warm engagement than parents of children. Furthermore, offspring age moderated the association between anxiety disorder status and parenting behaviors. Specifically, parents of adolescents with anxiety disorders showed higher intrusiveness and lower warm engagement than parents of non-anxious adolescents. A similar relationship between these parenting behaviors and anxiety disorder status was not observed among parents of children. The findings suggest that theoretical accounts of the role of parental behaviors in anxiety disorders in children and adolescents should distinguish between these different developmental periods. Further experimental research to establish causality, however, would be required before committing additional resources to targeting parenting factors within treatment