Increased Chamber Resting Tone Is a Key Determinant of Left Ventricular Diastolic Dysfunction.

BACKGROUND: Twitch-independent tension has been demonstrated in cardiomyocytes, but its role in heart failure (HF) is unclear. We aimed to address twitch-independent tension as a source of diastolic dysfunction by isolating the effects of chamber resting tone (RT) from impaired relaxation and stiffness. METHODS: We invasively monitored pressure-volume data during cardiopulmonary exercise in 20 patients with hypertrophic cardiomyopathy, 17 control subjects, and 35 patients with HF with preserved ejection fraction. To measure RT, we developed a new method to fit continuous pressure-volume measurements, and first validated it in a computational model of loss of cMyBP-C (myosin binding protein-C). RESULTS: In hypertrophic cardiomyopathy, RT (estimated marginal mean [95% CI]) was 3.4 (0.4-6.4) mm Hg, increasing to 18.5 (15.5-21.5) mm Hg with exercise (P<0.001). At peak exercise, RT was responsible for 64% (53%-76%) of end-diastolic pressure, whereas incomplete relaxation and stiffness accounted for the rest. RT correlated with the levels of NT-proBNP (N-terminal pro-B-type natriuretic peptide; R=0.57; P=0.02) and with pulmonary wedge pressure but following different slopes at rest and during exercise (R2=0.49; P<0.001). In controls, RT was 0.0 mm Hg and 1.2 (0.3-2.8) mm Hg in HF with preserved ejection fraction patients and was also exacerbated by exercise. In silico, RT increased in parallel to the loss of cMyBP-C function and correlated with twitch-independent myofilament tension (R=0.997). CONCLUSIONS: Augmented RT is the major cause of LV diastolic chamber dysfunction in hypertrophic cardiomyopathy and HF with preserved ejection fraction. RT transients determine diastolic pressures, pulmonary pressures, and functional capacity to a greater extent than relaxation and stiffness abnormalities. These findings support antimyosin agents for treating HF.

Inverse design of omnidirectional coherent absorbers for optical power beaming applications.

An efficient photovoltaic power converter is a critical element in laser power beaming systems for maximizing the end-to-end power transfer efficiency while minimizing beam reflections from the receiver for safety considerations. We designed a multilayer absorber that can efficiently trap monochromatic light from broad incident angles. The proposed design is built on the concept of a one-way coherent absorber with inverse-designed aperiodic multilayer front- and back-reflectors that enable maximal optical absorption in a thin-film photovoltaic material for broad angles. We argue that the broad bandwidth is achieved through an optimization search process that automatically engineers the modal content of the cavity to create multiple overlapping resonant modes at the desired angle or frequency range. A realistic design is provided based on GaAs thin films with inverse-designed multilayer binary AlAs/AlGaAs mirrors. The proposed device can pave the way for efficient optical power beaming systems.

High Curie temperature ferromagnetic structures of (Sb2Te3)1-x(MnSb2Te4)x with x = 0.7-0.8.

Magnetic topological materials are promising for realizing novel quantum physical phenomena. Among these, bulk Mn-rich MnSb2Te4 is ferromagnetic due to MnSb antisites and has relatively high Curie temperatures (TC), which is attractive for technological applications. We have previously reported the growth of materials with the formula (Sb2Te3)1-x(MnSb2Te4)x, where x varies between 0 and 1. Here we report on their magnetic and transport properties. We show that the samples are divided into three groups based on the value of x (or the percent septuple layers within the crystals) and their corresponding TC values. Samples that contain x < 0.7 or x > 0.9 have a single TC value of 15-20 K and 20-30 K, respectively, while samples with 0.7 < x < 0.8 exhibit two TC values, one (TC1) at ~ 25 K and the second (TC2) reaching values above 80 K, almost twice as high as any reported value to date for these types of materials. Structural analysis shows that samples with 0.7 < x < 0.8 have large regions of only SLs, while other regions have isolated QLs embedded within the SL lattice. We propose that the SL regions give rise to a TC1 of ~ 20 to 30 K, and regions with isolated QLs are responsible for the higher TC2 values. Our results have important implications for the design of magnetic topological materials having enhanced properties.

Endothelial dysfunction in patients with angina and non-obstructed coronary arteries is associated with an increased risk of mayor cardiovascular events. Results of the Spanish ENDOCOR registry.

BACKGROUND: Coronary endothelial dysfunction and vasospasm are potential causes of ischemia in patients without obstructive coronary stenoses (INOCA). OBJECTIVE: To evaluate the prevalence of endothelial dysfunction and the clinical profile of patients with INOCA in Spain, as well as to identify the predictors and the prognostic impact of endothelial dysfunction in this scenario. METHODS: A total of 438 consecutive patients with INOCA in whom the acetylcholine test was performed were prospectively enrolled. Patients were followed up at 1 and 2 years. RESULTS: Mean age was 62 ± 11 years with 60% female. Clinical presentation comprised 52.6% angina at rest, 61.2% exertional angina, and 31.7% dyspnea. There were no major complications of the acetylcholine test. Endothelial dysfunction was observed in 198 (45%) of patients, with severe vasoconstriction (defined as over 70% constriction), being observed in 101 (23%). Multivariable regression analysis showed that endothelial dysfunction was predicted by the presence of exertional angina (OR 2.2; CI95%1.01-2.55; p = 0.02), prior coronary disease (OR 2.46; CI95% 1.57-3.89; p < 0.01), and coronary intramyocardial bridging (2.35; CI95% 1.02-5.60; p = 0.04). Patients with endothelial dysfunction presented with worsening angina compared to those without endothelial dysfunction (25.6% vs. 12.8%) and also presented with increased levels of minimal effort angina (40% vs. 26,7%, p = 0.03) more frequently during the follow up than those without endothelial dysfunction. Endothelial dysfunction was also an independent predictor of the occurrence of myocardial infarction or unstable angina at one year (OR 2.85, CI 95% 1.01-9.25; p = 0.03). CONCLUSIONS: Endothelial dysfunction is present in almost half of patients with INOCA and is associated with worsening symptoms, as well as with a higher rate of adverse events.

Latest Developments in Robotic Percutaneous Coronary Interventions.

Since the first robotic-assisted percutaneous coronary intervention procedure (R-PCI) was performed in 2004, there has been a steady evolution in robotic technology, combined with a growth in the number of robotic installations worldwide and operator experience. This review summarises the latest developments in R-PCI with a focus on developments in robotic technology, procedural complexity, tele-stenting and training methods, which have all contributed to the global expansion in R-PCI.

Hypertrophic cardiomyopathy: an up-to-date snapshot of the clinical drug development pipeline.

INTRODUCTION: Hypertrophic cardiomyopathy (HCM) is a complex cardiac disease with highly variable phenotypic expression and clinical course most often caused by sarcomeric gene mutations resulting in left ventricular hypertrophy, fibrosis, hypercontractility, and diastolic dysfunction. For almost 60 years, HCM has remained an orphan disease and still lacks a disease-specific treatment. AREAS COVERED: This review summarizes recent preclinical and clinical trials with repurposed drugs and new emerging pharmacological and gene-based therapies for the treatment of HCM. EXPERT OPINION: The off-label drugs routinely used alleviate symptoms but do not target the core pathophysiology of HCM or prevent or revert the phenotype. Recent advances in the genetics and pathophysiology of HCM led to the development of cardiac myosin adenosine triphosphatase inhibitors specifically directed to counteract the hypercontractility associated with HCM-causing mutations. Mavacamten, the first drug specifically developed for HCM successfully tested in a phase 3 trial, represents the major advance for the treatment of HCM. This opens new horizons for the development of novel drugs targeting HCM molecular substrates which hopefully modify the natural history of the disease. The role of current drugs in development and genetic-based approaches for the treatment of HCM are also discussed.

Choque cardiogénico por síndrome coronario agudo en el servicio de cardiología de Las Tunas / Cardiogenic shock due to acute coronary syndrome in the cardiology service of Las Tunas

RESUMEN Introducción: el choque cardiogénico es la forma más grave de insuficiencia cardíaca aguda y la principal causa de muerte en pacientes con infarto agudo de miocardio. Objetivo: caracterizar a los pacientes con choque cardiogénico por síndrome coronario agudo en el servicio de cardiología de Las Tunas en el período octubre de 2017 a junio de 2021. Métodos: se realizó un estudio descriptivo y transversal con un universo de 325 pacientes y una muestra conformada de forma intencionada por 296 pacientes con el diagnóstico de insuficiencia cardíaca aguda por síndrome coronario agudo. Se estudiaron las variables edad, sexo, antecedentes patológicos personales, obesidad, tabaquismo, valvulopatías asociadas, frecuencia cardíaca, presión arterial sistólica, uso previo de fármacos, eventos adversos, variables ecocardiográficas y electrocardiográficas. Resultados: El 16,5 % de los pacientes estudiados desarrollaron choque cardiogénico; con prevalencia de la edad > 60 años (67,3 % grupo I vs. 80,3 % grupo II), el sexo masculino y los antecedentes de HTA (87,8 %). El uso previo de IECA o ARA II mostró una asociación inversamente proporcional a la presencia de choque cardiogénico (61,5 %). Ecocardiográficamente predominó la FEVI reducida (61,2 %), relación E/e´ alterada (32,6 %), velocidad de la onda S <5,4 cm/seg (42,9 %) y VFS elevados (46,9 %). Prevaleció el IMACEST (81,6 %) y la topografía anterior (51,1 %). Conclusiones: los pacientes con síndrome coronario agudo que con mayor frecuencia evolucionan al choque cardiogénico son los de edad avanzada, sin tratamiento farmacológico previo, con infartos de topografía anterior y fracción de eyección del ventrículo izquierdo reducida.

ABSTRACT Introduction: cardiogenic shock is the most severe form of acute heart failure and the main cause of death in patients with acute myocardial infarction. Objective: to characterize patients with cardiogenic shock due to acute coronary syndrome in the cardiology service of Las Tunas in the period October 2017 to June 2021. Methods: a descriptive and cross-sectional study was carried out with a universe of 325 patients and a sample intentionally formed by 296 patients with the diagnosis of acute heart failure due to acute coronary syndrome. The variables studied were age, sex, personal pathological history, obesity, smoking, associated valvulopathies, heart rate, systolic blood pressure, previous drug use, adverse events, echocardiographic and electrocardiographic variables. Results: 16,5 % of the patients studied developed cardiogenic shock; age > 60 years (67,3 % group I vs. 80,3 % group II), male sex and history of HT (87,8 %) prevailed. Previous use of ACEI or ARA II showed an inversely proportional association with the presence of cardiogenic shock (61,5 %). Echocardiographically, reduced LVEF (61,2 %), altered E/e' ratio (32,6 %), S-wave velocity <5,4 cm/sec (42,9 %) and elevated SFV (46,9 %) predominated. STEMI (81,6%) and anterior topography (51,1%) prevailed. Conclusions: patients with acute coronary syndrome who most frequently progress to cardiogenic shock are those of advanced age, without previous pharmacological treatment, with anterior topography infarctions and reduced left ventricular ejection fraction.

Association of age with clinical features and ablation outcomes of paroxysmal supraventricular tachycardias.

OBJECTIVE: The role of age in clinical characteristics and catheter ablation outcomes of atrioventricular nodal re-entrant tachycardia (AVNRT) or orthodromic atrioventricular re-entrant tachycardia (AVRT) has been assessed in retrospective studies categorising age by arbitrary cut-offs, but contemporary analyses of age-related trends are lacking. We aimed to study the relationship of age with epidemiological, clinical features and catheter ablation outcomes of AVNRT and AVRT. METHODS: We recruited 600 patients (median age 56 years, 60% female) with a confirmed diagnosis of AVNRT (n=455) or AVRT (n=145) by means of an electrophysiological study. They were interrogated for arrhythmia-related symptoms with a structured questionnaire and followed up to 1 year. We analysed age as a continuous variable using regression models and adjusting for relevant covariables. RESULTS: Both typical and atypical forms of AVNRT upraised with age while AVRT decreased (p<0.001 by regression). Female sex predominance in AVNRT was not observed in older patients. Overall, these tachycardias became more symptomatic with ageing despite a longer tachycardia cycle length (p<0.001) and regardless of the presence of structural heart disease, with a higher proportion of dizziness, syncope, chest pain or dyspnoea (p<0.005 for all) and a lower presence of palpitations or neck pounding (p<0.001 for both). Age was not associated with catheter ablation acute success, periprocedural complications or 1-year recurrence rates (p>0.05 for all). CONCLUSIONS: Age, evaluated as a continuous variable, had a significant association with the clinical profile of patients with AVNRT and AVRT. Nevertheless, catheter ablation outcomes and complications were not significantly related to patients' age.

Founder mutation in myosin-binding protein C with an early onset and a high penetrance in males.

OBJECTIVE: One of the challenges in hypertrophic cardiomyopathy (HCM) is to determine the pathogenicity of genetic variants and to establish genotype/phenotype correlations. This study aimed to: (1) demonstrate that MYBPC3 c.2149-1G>A is a founder pathogenic variant, (2) describe the phenotype and clinical characteristics of mutation carriers and (3) compare these patients with those with the most frequent pathogenic HCM variants: MYBPC3 p.Arg502Trp/Gln. METHODS: We reviewed genetic tests performed in HCM probands at our institution. We carried out transcript analyses to demonstrate the splicing effect, and haplotype analyses to support the founder effect of MYBPC3 c.2149-1G>A. Carriers with this mutation were compared with those from MYBPC3 p.Arg502Trp/Gln in terms of presentation features, imaging and outcomes. RESULTS: MYBPC3 c.2149-1G>A was identified in 8 of 570 probands and 25 relatives. Penetrance was age and sex dependent, 50.0% of the carriers over age 36 years and 75.0% of the carriers over 40 years showing HCM. Penetrance was significantly higher in males: in carriers older than 30 years old, 100.0% of males vs 50.0% of females had a HCM phenotype (p=0.01). Males were also younger at diagnosis (32±13 vs 53±10 years old, p<0.001). MYBPC3 c.2149-1G>A resulted in an abnormal transcript that led to haploinsufficiency and was segregated in two haplotypes. However, both came from one founder haplotype. Affected carriers showed a better functional class and higher left ventricular ejection fraction (LVEF) than patients with MYBPC3 p.Arg502Trp/Gln (p<0.05 for both). Nevertheless, the rate of major adverse outcomes was similar between the two groups. CONCLUSIONS: MYBPC3 c.2149-1G>A splicing variant is a founder mutation. Affected males show an early onset of HCM and with higher penetrance than women. Carriers show better functional class and higher LVEF than MYBPC3 p.Arg502Trp/Gln carriers, but a similar rate of major adverse outcomes.

Sistema de tareas docentes integradoras para la asignatura Célula, Tejidos y Sistema Tegumentario / System of integrative teaching tasks for the subject: Cell, Tissues and Integumentary System

RESUMEN Introducción: en pleno siglo XXI, no es posible enfrentar el fenómeno educacional sin una plena conciencia de que el desarrollo de la independencia cognoscitiva en los estudiantes, es una necesidad vital. Objetivo: diseñar sistema de tareas integradoras basada en las concepciones teóricas sobre la tarea docente concretada en contenidos del Tema 2 de la asignatura Célula, Tejidos y Sistema Tegumentario. Métodos: para confeccionar la estrategia metodológica se tuvieron en cuenta dificultades que se plantearon en los espacios metodológicos. Se realizó un experimento pedagógico. El sistema de tareas la realizaron 25 estudiantes seleccionados por un muestreo aleatorio simple después de recibir la conferencia orientadora y antes del seminario del tema; se compararon sus calificaciones con otro grupo de 25 estudiantes que recibieron la conferencia orientadora y no el sistema de tareas, a ambos grupos se les orientó acerca de la bibliografía a consultar y una guía de estudio. Resultados: las tareas docentes asignadas a los estudiantes motivaron en ellos la búsqueda activa de información, con una mayor independencia cognoscitiva y creatividad. Lograron mejores calificaciones. Se constató una mayor relación interdisciplinaria al dar solución a problemas integradores que encontrarán en su futura práctica profesional. Se logró desarrollo de habilidades de pensamiento. Conclusiones: el experimento pedagógico mostró que el sistema de tareas docentes permite integrar al estudiante a la actividad académica, investigativa y laboral, nutridos por las experiencias acumuladas en el orden profesional, de manera que adquieran conocimientos y habilidades básicas para apropiarse del modo de actuación profesional competente.

ABSTRACT Introduction: in the middle of XXI Century, it is not possible to deal with the educational phenomenon without full knowledge that the development of the cognitive independence in the students is a vital need. Objective: to design a system of integrative tasks based on the theoretical conceptions about the teaching task defined to the contents of the Topic-2 for the subject: Cell, Tissues and Integumentary System. Methods: the difficulties that arose in the methodological spaces were taken into account in the design of the methodological strategy. A pedagogical experiment was carried out. The system of teaching task included 25 students chosen at simple random sample after the guiding lecture was taught and before the seminar of the topic; their qualifications were compared with other group of students who were taught the guiding lecture and not the system of tasks, both groups were informed of the bibliography to be consulted and the guide to study was given. Results: the teaching tasks assigned to students encouraged them to the active search for information, achieving greater cognitive independence and creativity and reaching better qualifications. It was evidenced a better interdisciplinary relation giving solution to the wide-ranging problems they will find in their future professional practice. The development of thinking skills was achieved. Conclusions: the pedagogical experiment showed that the system of teaching tasks allows the integration of students into the academic, research and work activities, nourished by the experiences accumulated in the professional order, so that they acquire basic knowledge and skills to appropriate the competent professional mode of action.

Estado nutricional y variables antropométricas en adolescentes del Policlínico Universitario "Luis Augusto Turcios Lima" / Nutritional status and anthropometric variables in adolescents at the "Luis Augusto Turcios Lima" University Polyclinic

RESUMEN Introducción: el estudio del estado nutricional en adolescentes constituye una necesidad, al consolidarse en esta etapa modos de actuación y hábitos dietéticos que lo acompañarán durante su vida. Objetivo: caracterizar el estado nutricional y variables antropométricas en adolescentes del Policlínico Universitario "Luis Augusto Turcios Lima". Métodos: se desarrolló un estudio observacional, descriptivo y trasversal en adolescentes de 10 a 19 años del consultorio médico 19, del Policlínico Universitario "Luis Augusto Turcios Lima", en el periodo comprendido entre enero y diciembre de 2019. La muestra estuvo conformada por 180 pacientes. Se estudiaron las variables edad, sexo, índice de masa corporal, peso, talla, pliegue tricipital, subescapular y abdominal, circunferencia de cintura y de cadera. Se empleó estadística descriptiva. Resultados: se encontró predominio de pacientes entre 13 y 16 años (32,78 %), así como el sexo femenino (56,11 %) y normopesos (72,79 %). Las medias de las medidas antropométricas resultaron mayores en el sexo femenino, sin embargo, no se encontraron relaciones significativas de estas con el sexo. Con respecto a las circunferencias corporales, solo la circunferencia de la cadera fue mayor en hombres (Media: 77,24; DE: ±18,52) que en mujeres (Media: 74,32; DE: ± 23,49). No se reportó asociación entre el sexo y estas variables. Conclusiones: fue común en los adolescentes el predominio de féminas, así como la tendencia al peso normal, sin diferencias significativas entre ambos sexos en cuanto a las mediciones antropométricas.

ABSTRACT Introduction: the study of the nutritional status in adolescents is a necessity, as the modes of action and dietary habits that will accompany them throughout their lives are consolidated at this stage. Objective: to characterize the nutritional status and anthropometric variables in adolescents at the "Luis Augusto Turcios Lima" University Polyclinic. Methods: an observational, descriptive and cross-sectional study was carried out in adolescents aged 10 to 19 from medical office 19 of the "Luis Augusto Turcios Lima" University Polyclinic, in the period between January and December 2019. The sample consisted of 180 Patients: Age, sex, body mass index, weight, height, triceps, subscapular and abdominal fold, waist and hip circumference variables were studied, using descriptive statistics. Results: a predominance of patients between 13 and 16 years old (32,78 %) was found, as well as the female sex (56,11 %) and normal weight (72,79 %). The means of the anthropometric measurements were higher in the female sex, however, no significant relationships were found between these and sex. With regard to body circumferences, only the hip circumference was greater in men (Mean: 77,24; SD: ± 18,52) than in women (Mean: 74,32; SD: ± 23,49). No association was reported between sex and these variables. Conclusions: the predominance of females was common in adolescents, as well as the tendency to normal weight, without significant differences between both sexes in terms of anthropometric measurements.

Factores de riesgo asociados al bajo peso al nacer en el municipio Pinar del Río / Risk factors associated with low birth weight. Pinar del Rio municipality

RESUMEN Introducción: el bajo peso al nacer es el índice más importante para determinar las posibilidades del recién nacido de sobrevivir, tener un crecimiento y desarrollo normal. Constituye uno de los principales problemas obstétricos actuales, relacionado con más del 75 % de la morbimortalidad perinatal. Objetivo: identificar los principales factores de riesgo asociados al bajo peso al nacer en el municipio Pinar del Río, durante el año 2018. Métodos: se realizó un estudio descriptivo, transversal. El universo constituido por 95 recién nacidos vivos bajo peso en el período estudiado y la muestra fue de 75 % que cumplieron con los criterios de inclusión establecidos en la investigación. Las variables empleadas fueron: edad materna, edad gestacional al nacimiento, factores de riesgo (hipertensión arterial, diabetes mellitus, asma bronquial, anemia, sepsis vaginal, sepsis urinaria, hábito de fumar) y ganancia de peso durante la gestación. Las fuentes empleadas fueron las historias clínicas de las madres y recién nacidos. Los datos se presentaron en frecuencias absolutas y relativas. Resultados: la incidencia del bajo peso al nacer fue de 4,4 %, donde la edad materna de 27 a 34 años (48 %) fue la más representada, el 52 % de ellos nacieron antes de la semana 37 de gestación. La sepsis vaginal estuvo presente en el 42,6 %, la ganancia de peso durante la gestación fue mayor de 8 kilogramos en el 54,7 %. Conclusiones: tanto la modificación como el conocimiento de los factores de riesgo asociados al bajo peso al nacer, serán impactos favorables para su disminución.

ABSTRACT Introduction: low birth weight is the most important index to determine the survival possibilities of newborn having a normal growth and development; it currently constitutes one of the main obstetric problems, associated with more than 75 % of perinatal morbidity and mortality rate. Objective: to identify the main risk factors associated with low birth weight in Pinar del Rio municipality during 2018. Methods: a descriptive and cross-sectional study was carried out. The target group comprised 95 low birth weight newborn babies in the period studied and the sample included 75 meeting the inclusion criteria established in the research. The variables applied were: maternal age, gestational age at birth, risk factors (hypertension, diabetes mellitus, bronchial asthma, anemia, vaginal sepsis, urinary sepsis and smoking habit), and weight gain during pregnancy. The sources used were clinical histories of the mothers and newborn babies. Data were summarized in absolute and relative frequencies. Results: the incidence of low birth weight was 4,4 %, the most represented maternal age from 27 to 34 years old (48 %), 52 % of babies were born at 37 weeks of gestation. Vaginal sepsis was present in 42,6 %, weight gain during gestation behaved greater than 8 kilograms in the 54,7 %. Conclusions: both the modification of knowledge and the risk factors associated with low birth weight will be of favorable impact for its decrease.

Evaluación nutricional de adolescentes del Policlínico Universitario "Luis Augusto Turcios Lima" / Nutritional assessment of adolescents at Luis Augusto Turcios Lima Teaching Polyclinic

RESUMEN Introducción: la obesidad en la adolescencia representa un fenómeno desfavorable con incidencia negativa en la salud del individuo. Objetivo: evaluar el estado nutricional de adolescentes del Policlínico Universitario "Luis Augusto Turcios Lima" durante el 2018. Métodos: se realizó un estudio observacional, analítico y transversal en adolescentes perteneciente al Policlínico Universitario "Luis Augusto Turcios Lima", durante el año 2018. El universo estuvo constituido por 105 pacientes entre 11 y 19 años de edad, se trabajó con la totalidad. Se aplicó la prueba X2 para determinar independencia entre variables. Resultados: predominó el sexo femenino (51,42 %), así como los pacientes normopesos según evaluación nutricional (71,43 %) e índice de adiposidad (43,81 %). Se encontró asociación (X2=16,798 p<0,05) entre el índice de adiposidad y el sexo, donde ser fémina se comportó como factor protector (RR: 0,44 IC:0,25-0,77). Se encontró predominio de pacientes sedentarios (91,43 %) los cuales presentaron un riesgo superior para ser sobrepeso y obeso (RR: 1,10 IC: 1,049-1,18). El 100 % presentó malos hábitos nutricionales y refirió usar por más de cuatro horas diarias las nuevas tecnologías. Conclusiones: los jóvenes presentaron en su mayoría, valores normales de peso, sin embargo, en el sexo masculino se encontró mayor incidencia del sobrepeso. El sedentarismo y la falta de ejercicio físico, así como el uso excesivo de las nuevas tecnologías se presentan con amplia frecuencia en adolescentes, con repercusión negativa en el peso corporal.

ABSTRACT Introduction: obesity in the adolescence represents an unfavorable phenomenon having negative incidence in the health condition of the individual. Objective: to assess the nutritional status of adolescents at Luis Augusto Turcios Lima University Polyclinic during 2018. Methods: an observational, analytical and cross-sectional study was conducted with adolescents from Luis Augusto Turcios Lima University Polyclinic during 2018. The target group was comprised of 105 patients between 11 and 19 years old, working with them all. To determine the independence among the variables, chi-squared test was applied. Results: female sex predominated (51,42 %), with normo-weight patients according to the nutritional assessment (71,43 %) and adiposity index (43,81 %). An association between the adiposity index and sex was found (X2=16,798 p<0,05), where being from female sex appeared to be as a protector factor (RR: 0,44 IC: 0,25-0,77); finding a predominance of sedentary patients (91,43 %) who presented high risks to be overweight or obese (RR: 1,10 IC: 1,049-1,18). The 100 % showed bad nutritional habits and they referred to use the new information technologies for more than four hours a day. Conclusions: the majority of the adolescents presented normal indexes of weight; however, it was found a higher incidence of overweight in male sex. Sedentary lifestyle and the lack of physical exercises, along with the immoderate use of the new information technologies, present a high incidence in adolescents, having a negative repercussion on body mass index.

The p.P888L SAP97 polymorphism increases the transient outward current (Ito,f) and abbreviates the action potential duration and the QT interval.

Synapse-Associated Protein 97 (SAP97) is an anchoring protein that in cardiomyocytes targets to the membrane and regulates Na+ and K+ channels. Here we compared the electrophysiological effects of native (WT) and p.P888L SAP97, a common polymorphism. Currents were recorded in cardiomyocytes from mice trans-expressing human WT or p.P888L SAP97 and in Chinese hamster ovary (CHO)-transfected cells. The duration of the action potentials and the QT interval were significantly shorter in p.P888L-SAP97 than in WT-SAP97 mice. Compared to WT, p.P888L SAP97 significantly increased the charge of the Ca-independent transient outward (Ito,f) current in cardiomyocytes and the charge crossing Kv4.3 channels in CHO cells by slowing Kv4.3 inactivation kinetics. Silencing or inhibiting Ca/calmodulin kinase II (CaMKII) abolished the p.P888L-induced Kv4.3 charge increase, which was also precluded in channels (p.S550A Kv4.3) in which the CaMKII-phosphorylation is prevented. Computational protein-protein docking predicted that p.P888L SAP97 is more likely to form a complex with CaMKII than WT. The Na+ current and the current generated by Kv1.5 channels increased similarly in WT-SAP97 and p.P888L-SAP97 cardiomyocytes, while the inward rectifier current increased in WT-SAP97 but not in p.P888L-SAP97 cardiomyocytes. The p.P888L SAP97 polymorphism increases the Ito,f, a CaMKII-dependent effect that may increase the risk of arrhythmias.

Designer Topological Insulator with Enhanced Gap and Suppressed Bulk Conduction in Bi2Se3/Sb2Te3 Ultrashort-Period Superlattices.

A novel approach to suppress bulk conductance in three-dimensional (3D) topological insulators (TIs) using short-period superlattices (SLs) of two TIs is presented. Evidence for superlattice gap enhancement (SGE) was obtained from the reduction of bulk background doping from 1.2 × 1020 cm-3 to 8.5 × 1018 cm-3 as the period of Bi2Se3/Sb2Te3 SLs is decreased from 12 nm to 5 nm. Tight binding calculations show that, in the ultrashort-period regime, a significant SGE can be achieved for the resulting SL. Ultrathin short-period SLs behave as new designer TIs with bulk bandgaps up to 60% larger than the bandgap of the constituent layer of largest bandgap, while retaining topological surface features. Evidence for gap formation was obtained from ellipsometric measurements. Analysis of the weak antilocalization cusp in low-temperature magneto-conductance confirms that the top and bottom surfaces of the SL structure behave as Dirac surfaces. This approach represents a promising platform for building truly insulating TIs.