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Background: Andersen-Tawil Syndrome type 1 (ATS1) is a rare arrhythmogenic disorder, caused by loss-of-function mutations in the KCNJ2 gene. We present here the largest cohort of patients with ATS1 with outcome data reported. Objectives: This study sought to define the risk of life-threatening arrhythmic events (LAE), identify predictors of such events, and define the efficacy of antiarrhythmic therapy in patients with ATS1. Methods: Clinical and genetic data from consecutive patients with ATS1 from 23 centers were entered in a database implemented at ICS Maugeri in Pavia, Italy, and pooled for analysis. Results: We enrolled 118 patients with ATS1 from 57 families (age 23 ± 17 years at enrollment). Over a median follow-up of 6.2 years (interquartile range: 2.7 to 16.5 years), 17 patients experienced a first LAE, with a cumulative probability of 7.9% at 5 years. An increased risk of LAE was associated with a history of syncope (hazard ratio [HR]: 4.54; p = 0.02), with the documentation of sustained ventricular tachycardia (HR 9.34; p = 0.001) and with the administration of amiodarone (HR: 268; p < 0.001). The rate of LAE without therapy (1.24 per 100 person-years [py]) was not reduced by beta-blockers alone (1.37 per 100 py; p = 1.00), or in combination with Class Ic antiarrhythmic drugs (1.46 per 100 py, p = 1.00). Conclusions: Our data demonstrate that the clinical course of patients with ATS1 is characterized by a high rate of LAE. A history of unexplained syncope or of documented sustained ventricular tachycardia is associated with a higher risk of LAE. Amiodarone is proarrhythmic and should be avoided in patients with ATS1.

Background: CaM (calmodulin) mutations are associated with congenital arrhythmia susceptibility (calmodulinopathy) and are most often de novo. In this report, we sought to broaden the genotype-phenotype spectrum of calmodulinopathies with 2 novel calmodulin mutations and to investigate mosaicism in 2 affected families. Methods: CaM mutations were identified in 4 independent cases by DNA sequencing. Biochemical and electrophysiological studies were performed to determine functional consequences of each mutation. Results: Genetic studies identified 2 novel CaM variants (CALM3-E141K in 2 cases; CALM1-E141V) and one previously reported CaM pathogenic variant (CALM3-D130G) among 4 probands with shared clinical features of prolonged QTc interval (range 505-725 ms) and documented ventricular arrhythmia. A fatal outcome occurred for 2 of the cases. The parents of all probands were asymptomatic with normal QTc duration. However, 2 of the families had multiple affected offspring or multiple occurrences of intrauterine fetal demise. The mother from the family with recurrent intrauterine fetal demise exhibited the CALM3-E141K mutant allele in 25% of next-generation sequencing reads indicating somatic mosaicism, whereas CALM3-D130G was present in 6% of captured molecules of the paternal DNA sample, also indicating mosaicism. Two novel mutations (E141K and E141V) impaired Ca2+ binding affinity to the C-domain of CaM. Human-induced pluripotent stem cell-derived cardiomyocytes overexpressing mutant or wild-type CaM showed that both mutants impaired Ca2+-dependent inactivation of L-type Ca2+ channels and prolonged action potential duration. Conclusions: We report 2 families with somatic mosaicism associated with arrhythmogenic calmodulinopathy, and demonstrate dysregulation of L-type Ca2+ channels by 2 novel CaM mutations affecting the same residue. Parental mosaicism should be suspected in families with unexplained fetal arrhythmia or fetal demise combined with a documented CaM mut

Background: CaM (calmodulin) mutations are associated with congenital arrhythmia susceptibility (calmodulinopathy) and are most often de novo. In this report, we sought to broaden the genotype-phenotype spectrum of calmodulinopathies with 2 novel calmodulin mutations and to investigate mosaicism in 2 affected families. Methods: CaM mutations were identified in 4 independent cases by DNA sequencing. Biochemical and electrophysiological studies were performed to determine functional consequences of each mutation. Results: Genetic studies identified 2 novel CaM variants (CALM3-E141K in 2 cases; CALM1-E141V) and one previously reported CaM pathogenic variant (CALM3-D130G) among 4 probands with shared clinical features of prolonged QTc interval (range 505-725 ms) and documented ventricular arrhythmia. A fatal outcome occurred for 2 of the cases. The parents of all probands were asymptomatic with normal QTc duration. However, 2 of the families had multiple affected offspring or multiple occurrences of intrauterine fetal demise. The mother from the family with recurrent intrauterine fetal demise exhibited the CALM3-E141K mutant allele in 25% of next-generation sequencing reads indicating somatic mosaicism, whereas CALM3-D130G was present in 6% of captured molecules of the paternal DNA sample, also indicating mosaicism. Two novel mutations (E141K and E141V) impaired Ca2+ binding affinity to the C-domain of CaM. Human-induced pluripotent stem cell-derived cardiomyocytes overexpressing mutant or wild-type CaM showed that both mutants impaired Ca2+-dependent inactivation of L-type Ca2+ channels and prolonged action potential duration. Conclusions: We report 2 families with somatic mosaicism associated with arrhythmogenic calmodulinopathy, and demonstrate dysregulation of L-type Ca2+ channels by 2 novel CaM mutations affecting the same residue. Parental mosaicism should be suspected in families with unexplained fetal arrhythmia or fetal demise combined with a documented CaM mut

AIMS: The aim of this study was to determine the frequency of heterozygous truncating ALPK3 variants (ALPK3tv) in patients with hypertrophic cardiomyopathy (HCM) and confirm their pathogenicity using burden testing in independent cohorts and family co-segregation studies. METHODS AND RESULTS: In a discovery cohort of 770 index patients with HCM, 12 (1.56%) were heterozygous for ALPK3tv [odds ratio(OR) 16.11, 95% confidence interval (CI) 7.94-30.02, P = 8.05e-11] compared to the Genome Aggregation Database (gnomAD) population. In a validation cohort of 2047 HCM probands, 32 (1.56%) carried heterozygous ALPK3tv (OR 16.17, 95% CI 10.31-24.87, P < 2.2e-16, compared to gnomAD). Combined logarithm of odds score in seven families with ALPK3tv was 2.99. In comparison with a cohort of genotyped patients with HCM (n = 1679) with and without pathogenic sarcomere gene variants (SP+ and SP-), ALPK3tv carriers had a higher prevalence of apical/concentric patterns of hypertrophy (60%, P < 0.001) and of a short PR interval (10%, P = 0.009). Age at diagnosis and maximum left ventricular wall thickness were similar to SP- and left ventricular systolic impairment (6%) and non-sustained ventricular tachycardia (31%) at baseline similar to SP+. After 5.3 ± 5.7 years, 4 (9%) patients with ALPK3tv died of heart failure or had cardiac transplantation (log-rank P = 0.012 vs. SP- and P = 0.425 vs. SP+). Imaging and histopathology showed extensive myocardial fibrosis and myocyte vacuolation. CONCLUSIONS: Heterozygous ALPK3tv are pathogenic and segregate with a characteristic HCM phenotype.

Background: Long QT syndrome (LQTS) is a common inheritable arrhythmogenic disorder, often secondary to mutations in the KCNQ1, KCNH2, and SCN5A genes. The disease is characterized by a prolonged ventricular repolarization (QTc interval) that confers susceptibility to life-threatening arrhythmic events (LAEs). Objectives: This study sought to create an evidence-based risk stratification scheme to personalize the quantification of the arrhythmic risk in patients with LQTS. Methods: Data from 1,710 patients with LQTS followed up for a median of 7.1 years (interquartile range [IQR]: 2.7 to 13.4 years) were analyzed to estimate the 5-year risk of LAEs based on QTc duration and genotype and to assess the antiarrhythmic efficacy of beta-blockers. Results: The relationship between QTc duration and risk of events was investigated by comparison of linear and cubic spline models, and the linear model provided the best fit. The 5-year risk of LAEs while patients were off therapy was then calculated in a multivariable Cox model with QTc and genotype considered as independent factors. The estimated risk of LAEs increased by 15% for every 10-ms increment of QTc duration for all genotypes. Intergenotype comparison showed that the risk for patients with LQT2 and LTQ3 increased by 130% and 157% at any QTc duration versus patients with LQT1. Analysis of response to beta-blockers showed that only nadolol reduced the arrhythmic risk in all genotypes significantly compared with no therapy (hazard ratio: 0.38; 95% confidence interval: 0.15 to 0.93; p = 0.03). Conclusions: The study provides an estimator of risk of LAEs in LQTS that allows a granular estimate of 5-year arrhythmic risk and demonstrate the superiority of nadolol in reducing the risk of LAEs in LQTS

Contains fulltext : 173180.pdf (publisher's version ) (Open Access), Stem cells possess significant age-dependent differences in their immune-response profile. These differences were analysed by Next-Generation Sequencing of six age groups from bone marrow mesenchymal stem cells. A total of 9,628 genes presenting differential expression between age groups were grouped into metabolic pathways. We focused our research on young, pre-pubertal and adult groups, which presented the highest amount of differentially expressed genes related to inflammation mediated by chemokine and cytokine signalling pathways compared with the newborn group, which was used as a control. Extracellular vesicles extracted from each group were characterized by nanoparticle tracking and flow cytometry analysis, and several micro-RNAs were verified by quantitative real-time polymerase chain reaction because of their relationship with the pathway of interest. Since miR-21-5p showed the highest statistically significant expression in extracellular vesicles from mesenchymal stem cells of the pre-pubertal group, we conducted a functional experiment inhibiting its expression and investigating the modulation of Toll-Like Receptor 4 and their link to damage-associated molecular patterns. Together, these results indicate for the first time that mesenchymal stem cell-derived extracellular vesicles have significant age-dependent differences in their immune profiles.

Contains fulltext : 173180.pdf (publisher's version ) (Open Access), Stem cells possess significant age-dependent differences in their immune-response profile. These differences were analysed by Next-Generation Sequencing of six age groups from bone marrow mesenchymal stem cells. A total of 9,628 genes presenting differential expression between age groups were grouped into metabolic pathways. We focused our research on young, pre-pubertal and adult groups, which presented the highest amount of differentially expressed genes related to inflammation mediated by chemokine and cytokine signalling pathways compared with the newborn group, which was used as a control. Extracellular vesicles extracted from each group were characterized by nanoparticle tracking and flow cytometry analysis, and several micro-RNAs were verified by quantitative real-time polymerase chain reaction because of their relationship with the pathway of interest. Since miR-21-5p showed the highest statistically significant expression in extracellular vesicles from mesenchymal stem cells of the pre-pubertal group, we conducted a functional experiment inhibiting its expression and investigating the modulation of Toll-Like Receptor 4 and their link to damage-associated molecular patterns. Together, these results indicate for the first time that mesenchymal stem cell-derived extracellular vesicles have significant age-dependent differences in their immune profiles.

Contains fulltext : 173180.pdf (publisher's version ) (Open Access), Stem cells possess significant age-dependent differences in their immune-response profile. These differences were analysed by Next-Generation Sequencing of six age groups from bone marrow mesenchymal stem cells. A total of 9,628 genes presenting differential expression between age groups were grouped into metabolic pathways. We focused our research on young, pre-pubertal and adult groups, which presented the highest amount of differentially expressed genes related to inflammation mediated by chemokine and cytokine signalling pathways compared with the newborn group, which was used as a control. Extracellular vesicles extracted from each group were characterized by nanoparticle tracking and flow cytometry analysis, and several micro-RNAs were verified by quantitative real-time polymerase chain reaction because of their relationship with the pathway of interest. Since miR-21-5p showed the highest statistically significant expression in extracellular vesicles from mesenchymal stem cells of the pre-pubertal group, we conducted a functional experiment inhibiting its expression and investigating the modulation of Toll-Like Receptor 4 and their link to damage-associated molecular patterns. Together, these results indicate for the first time that mesenchymal stem cell-derived extracellular vesicles have significant age-dependent differences in their immune profiles.

Supplement: 1 Meeting Abstract: P5472

El efecto del manejo (pastoreo continuo o rotacional) sobre la digestibilidad de la materia orgánica (DMO), proteína bruta (PB) y elementos minerales (P, Ca Mg, K y Na) de la hierba y su variación estacional se evaluaron durante dos años consecutivos en una pradera de raigrás inglés-trébol blanco deteriorada, con un alto contenido en Plantago lanceolata, fundamentalmente. El diseño fue de bloques al azar, con dos repeticiones. Las muestras de hierba se lavaron abundantemente con agua, para evitar la contaminación por tierra. La DMO y PB de la hierba aprovechada en pastoreo continuo o rotacional fue similar (69,0 y 69,9 % DMO; 157,0 y 160,6 g/kg PB, para pastoreo continuo y rotacional respectivamente). Sin embargo, la hierba pastada continuamente tuvo menos Ca, K y Na, y más P y Mg que la hierba aprovechada en pastoreo rotacional (Ca: 8,21 y 10,07 g/kg; K: 26,19 y 29,93 g/kg; Na: 2,60 y 3,13 g/kg; P: 2,87 y 2,64 g/kg; Mg: 3,53 y 3,17 g/kg, en pastoreo continuo y rotacional), como consecuencia de las diferencias en el crecimiento de la hierba y en la composición botánica de la pradera. El % DMO y la PB del pasto disminuyeron de primavera a verano y aumentaron de nuevo en otoño. Los niveles máximos de K se hallaron en primavera, y los mínimos en verano. Para el Ca, los valores más altos se encontraron en otoño, y no se observaron diferencias entre primavera y verano. Estos cambios estacionales siguieron el modelo descrito en experimentos realizados en condiciones distintas a las nuestras, no sucediendo así con el P, Mg y el Na. No se observaron diferencias entre primavera y otoño en los niveles de P o Mg, que fueron mínimos en verano, y se halló un pico en los niveles de Na en otoño. Nuestros resultados indican que, en las condiciones de Galicia, la calidad de la hierba manejada en pastoreo rotacional no sería inferior a la de la hierba aprovechada en pastoreo continuo, sugiriendo asimismo que no existe un modelo general de variación estacional de la composición minera

Se analiza el efecto del sistema de pastoreo (continuo, rotacional) sobre la densidad y la composición botánica de la pradera, en un sistema de producción de carne con vacas de cría de raza Rubia Gallega. El diseño fue de bloques al azar, con dos repeticiones por tratamiento. La densidad se determinó por conteo de vástagos (raigrás y especies no sembradas) y puntos de crecimiento (trébol); el porcentaje de especies sembradas (raigrás inglés y trébol blanco) y espontáneas se estimó por separación manual de las muestras. Los resultados se compararon mediante análisis de varianza. El número de vástagos de raigrás y puntos de crecimiento de trébol fue mayor en la pradera aprovechada en pastoreo continuo que en la pradera aprovechada rotacionalmente; el número de vástagos de especies espontáneas fue similar en ambos sistemas (4669 vs 1633 vástagos de raigrás, 575 vs 285 puntos de crecimiento de trébol, y 4604 vs 4896 vástagos de especies no sembradas, respectivamente). El porcentaje de especies sembradas (en peso seco) fue mayor en el pasto aprovechado continuamente; la diferencia se debió al raigrás (43,0 y 25,9%, para pastoreo continuo y rotacional respectivamente), ya que el porcentaje de trébol fue similar (5,0 y 3,0%, para los mismos tratamientos). Los valores de densidad obtenidos fueron inferiores a los descritos en la bibliografía, tanto en pastoreo continuo como en pastoreo rotacional. Palabras clave: Pasto, pastoreo, estructura del pasto, vacuno.

Se utilizaron 16 terneros rubios gallegos para estudiar el efecto del aca- bado con pienso, que contiene soja integral sobre el peso y las característi- cas de la canal y de la carne del ternero tradicional producido en un siste- ma de pastoreo. Se controlo el peso vivo, el peso al sacrificio, el peso canal, la conformación y el estado de engrasamiento de la canal y en la carne a 24 horas postmorten, el pH, el color L* (luminosidad) a* (índice de rojo) y b* (índice de amarillo) (CIE 1978), la composición química por espectroscopia NIRS, las pérdidas de agua por cocción, la textura midiendo la fuerza máxi- ma de corte, resistencia al corte y trabajo total y el contenido en pigmentos hemínicos. Los resultados se analizaron mediante ANOVA con el programa SPSS 8.0. No se encontraron diferencias significativas entre tratamientos en ninguno de los parámetros estudiados de peso vivo y características de la canal y de la carne. Se concluye que la sustitución de la soja desengrasada por soja integral en la ración de acabado no afecta al crecimiento y a las características de la canal y de la carne del ternero tradicional Gallego.

Se utilizaron 16 terneros rubios gallegos para estudiar el efecto del aca- bado con pienso, que contiene soja integral sobre el peso y las característi- cas de la canal y de la carne del ternero tradicional producido en un siste- ma de pastoreo. Se controlo el peso vivo, el peso al sacrificio, el peso canal, la conformación y el estado de engrasamiento de la canal y en la carne a 24 horas postmorten, el pH, el color L* (luminosidad) a* (índice de rojo) y b* (índice de amarillo) (CIE 1978), la composición química por espectroscopia NIRS, las pérdidas de agua por cocción, la textura midiendo la fuerza máxi- ma de corte, resistencia al corte y trabajo total y el contenido en pigmentos hemínicos. Los resultados se analizaron mediante ANOVA con el programa SPSS 8.0. No se encontraron diferencias significativas entre tratamientos en ninguno de los parámetros estudiados de peso vivo y características de la canal y de la carne. Se concluye que la sustitución de la soja desengrasada por soja integral en la ración de acabado no afecta al crecimiento y a las características de la canal y de la carne del ternero tradicional Gallego.

Se utilizaron 16 terneros rubios gallegos para estudiar el efecto del aca- bado con pienso, que contiene soja integral sobre el peso y las característi- cas de la canal y de la carne del ternero tradicional producido en un siste- ma de pastoreo. Se controlo el peso vivo, el peso al sacrificio, el peso canal, la conformación y el estado de engrasamiento de la canal y en la carne a 24 horas postmorten, el pH, el color L* (luminosidad) a* (índice de rojo) y b* (índice de amarillo) (CIE 1978), la composición química por espectroscopia NIRS, las pérdidas de agua por cocción, la textura midiendo la fuerza máxi- ma de corte, resistencia al corte y trabajo total y el contenido en pigmentos hemínicos. Los resultados se analizaron mediante ANOVA con el programa SPSS 8.0. No se encontraron diferencias significativas entre tratamientos en ninguno de los parámetros estudiados de peso vivo y características de la canal y de la carne. Se concluye que la sustitución de la soja desengrasada por soja integral en la ración de acabado no afecta al crecimiento y a las características de la canal y de la carne del ternero tradicional Gallego.