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En el presente estudio se utilizó el modelo Gardner- Eberhart (1966) y se involucró a 8 poblaciones parentales de maíz y sus poblaciones derivadas. El objetivo fue estimar los efectos génicos acumulativos (aditivos, dominantes y heteróticos), con la finalidad de justificar un programa de hibridación. Para rendimiento de grano, dominancia intravarietal (dj) explicó 55,54% de las medias generacionales, sugiriendo suficiente variabilidad genética dentro de las poblaciones. Efectos heteróticos contribuyeron con 12,11 % indicando la poca diferencia que existe en la frecuencia génica para rendimiento de grano. Altura de planta siguió el mismo patrón que rendimiento, ya que los efectos dominantes fueron los más importantes. Sin embargo, los loci homocigotes (aj) fueron importantes en explicar variabilidad gen ética en días a floración y no. de mazorcas. Para rendimiento de grano, la cruza Pob. 32 x Pob. 21 fue la que maximizó los efectos heteróticos. La población 21 exhibió mayor heterosis en promedio, de tal suerte que en combinación con Pob. 32 y/o CN(S)-C3, entre otras, podría ser material pr.omisorio para un programa de selección recíproca recurrente.

Se evaluaron siete genotipos de papa en campo, en un diseño de bloques al azar con cuatro repeticiones, la parcela experimental de tres surcos de cinco metros de largo. Las variables analizadas fueron morfológicas, fisiológicas, agroclimáticas y de rendimiento. Se determinaron correlaciones simples y análisis de componentes principales (ACP), para encontrar el grado de asociación entre variables, y cuales fueron las variables que más contribuyeron a la variación en el rendimiento. Las variables más correlacionadas con rendimiento fueron altura de planta, peso seco de hojas y contenido de clorofila. El ACP permitió una mejor discriminación entre variables; las más importantes fueron la fotosíntesis y uso eficiente del agua. Las mejores variedades al considerar todas las variables en conjunto, fueron Norteña, Mondial y Atlantic, superando al testigo regional (Alpha).

Background: Among inherited cardiomyopathies involving the left ventricle, whether dilated or not, certain genotypes carry a well-established arrhythmic risk, notably manifested as sustained monomorphic ventricular tachycardia (SMVT). Nonetheless, the precise localization and electrophysiological profile of this substrate remain undisclosed across different genotypes., Methods: Patients diagnosed with cardiomyopathy and left ventricle involvement due to high-risk genetic variants and SMVT treated by electrophysiological study were recruited from 18 European/US centers. Electrophysiological study, imaging, and outcomes data after ablation were assessed in relation to genotype., Results: Seventy-one patients were included (49.6 Q1-Q3 [40-60] years, 76% men). They were divided into 4 groups according to the affected protein: desmosomal ( DSP , PKP2 , DSG2 , and DSC2 ), nuclear membrane ( LMNA and TMEM43 ), cytoskeleton ( FLNC and DES ), and sarcoplasmic reticulum ( PLN ). Desmosomal genes, TMEM43 , and PLN were associated with biventricular disease, while variants in LMNA and cytoskeleton genes had predominant left ventricle involvement ( P =0.001). The location of the clinical-SMVT substrate was significantly different based on genotype ( P =0.005). DSP and cytoskeleton genes presented SMVTs with right bundle branch block morphology, which origin was identified in the inferolateral segments of the left ventricle. The other desmosomal genes ( PKP2 and DSG2 ), along with TMEM43 , showed SMVTs with left bundle branch block morphology and predominantly right ventricular substrate. In contrast, LMNA substrate was mainly observed in the interventricular septum. During a median of 26 Q1-Q3 (10.6-65) months, 27% of patients experienced recurrences of clinical SMVT with differences between genotypes (log-rank 0.016). Nuclear membrane genes demonstrated the highest recurrence rate compared with desmosomal genes (hazard ratio, 4.56 [95% CI, 1.5-13.8])., Conclusions: The anatomic substrate of SMVTs shows a strong correlation with the underlying genotype, electrocardiographic morphology, and recurrence rate. Particularly, patients with nuclear membrane gene variants have a significantly higher recurrence rate compared with those with desmosomal gene variants., Competing Interests: None.

Background: Vector field heterogeneity (VFH) is a novel omnipolar metric to quantify local propagation heterogeneities that may identify functionally critical sites for ablation in scar-related ventricular tachycardia (VT)., Objective: This study aims to assess the diagnostic value of VFH to identify abnormal propagation patterns during ventricular substrate mapping and compare VFH in VT isthmus sites (IS), low-voltage bystander area (LVA) , and normal voltage areas (NVAa)., Methods: Substrate maps acquired with a 16-pole grid catheter in patients with scar-related VT were segmented into sites corresponding to IS, LVA, and NVA (defined as omnipolar voltages > and <1.5 mV) based on corresponding VT activation maps. For each 4 × 4 electrode-array acquisition, omnipolar-derived vector maps of the directions of electrical propagation were computed offline, and a VFH value per clique ranging from 0 (perfect planar wave) to 1 (maximal disorganization) derived., Results: Sixteen patients were studied (56.3% ischemic), evaluating 9 endocardial and 7 epicardial substrate maps. VFH metric at IS was 0.57 ± 0.26, LVA 0.52 ± 0.34, and NVA 0.16 ± 0.24. VFH at IS was higher (more disorganized) than at LVA (P < .001). VFH in NVA was significantly lower (ie, more homogeneous) compared with IS and LVA (P < .001, respectively). Within the isthmus, highest heterogeneity was recorded at entry (0.61 ± 0.24), lowest at exit sites (0.44 ± 0.27)., Conclusion: VFH mapping identified a significant increase in electrical heterogeneity at IS compared with bystanders with highest heterogeneity at the entrance. Yet, absolute differences were small, and substantial overlap among sites was recorded, precluding its use as a stand-alone mapping approach. VFH may be integrated in existing mapping strategies as complementary information to support identification of ablation targets., Competing Interests: Disclosures The authors have no conflicts of interest to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Idiopathic verapamil-sensitive fascicular ventricular tachycardia (VT) is the most common form of Purkinje-related ventricular tachycardia (PRVT). Left septal fascicle (LSF) involvement and its connections with the other fascicles, have been recently reported as a pathophysiologic mechanism for this form of PRVT. We describe a case of idiopathic PRVT with LSF involvement using omnipolar technology (OT) mapping in relation to a false tendon. Ablation in the area with concealed fusion entrainment did not terminate the tachycardia. However, radiofrequency application in the area of LSF with manifest fusion entrainment, resulted in immediate tachycardia termination. Six months follow-up showed no tachycardia recurrence., (© 2023 Wiley Periodicals LLC.)

Molecular Dynamics (MD) simulations constitute a powerful tool that provides a 3D perspective of the dynamical behavior of chemical systems. Herein the first MD study of the dynamics of a catalytic organometallic system, in micellar media, is presented. The challenging methane catalytic functionalization into ethyl propionate through a silver-catalyzed process has been targeted as the case study. The intimate nature of the micelles formed with the surfactants sodium dodecylsulfate (SDS) and potassium perfluorooctane sulfonate (PFOS) has been ascertained, as well as the relative distribution of the main actors in this transformation, namely methane, the diazo reagent and the silver catalyst, the latter in two different forms: the initial compound and a silver-carbene intermediate. Catalyst deactivation occurs with halide containing surfactants dodecyltrimethylammonium chloride (DTAC) and Triton X-100. Computed simulations allow explaining the experimental results, indicating that micelles behave differently regarding the degree of accumulation and the local distribution of the reactants and their effect in the molecular collisions leading to net reaction., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Competing Interests: Funding Support and Author Disclosures The authors have reported that they have no relationships relevant to the contents of this paper to disclose.

13-Lipoxygenases (LOXs) initiate the synthesis of jasmonic acid (JA), the best-understood oxylipin hormone in herbivory defense. However, the roles of 9-LOX-derived oxylipins in insect resistance remain unclear. Here, we report a novel anti-herbivory mechanism mediated by a tonoplast-localized 9-LOX, ZmLOX5, and its linolenic acid-derived product, 9-hydroxy-10-oxo-12(Z),15(Z)-octadecadienoic acid (9,10-KODA). Transposon-insertional disruption of ZmLOX5 resulted in the loss of resistance to insect herbivory. lox5 knockout mutants displayed greatly reduced wound-induced accumulation of multiple oxylipins and defense metabolites, including benzoxazinoids, abscisic acid (ABA), and JA-isoleucine (JA-Ile). However, exogenous JA-Ile failed to rescue insect defense in lox5 mutants, while applications of 1 μM 9,10-KODA or the JA precursor, 12-oxo-phytodienoic acid (12-OPDA), restored wild-type resistance levels. Metabolite profiling revealed that exogenous 9,10-KODA primed the plants for increased production of ABA and 12-OPDA, but not JA-Ile. While none of the 9-oxylipins were able to rescue JA-Ile induction, the lox5 mutant accumulated lower wound-induced levels of Ca 2+ , suggesting this as a potential explanation for lower wound-induced JA. Seedlings pretreated with 9,10-KODA exhibited rapid or more robust wound-induced defense gene expression. In addition, an artificial diet supplemented with 9,10-KODA arrested fall armyworm larvae growth. Finally, analysis of single and double lox5 and lox10 mutants showed that ZmLOX5 also contributed to insect defense by modulating ZmLOX10-mediated green leaf volatile signaling. Collectively, our study uncovered a previously unknown anti-herbivore defense and hormone-like signaling activity for a major 9-oxylipin α-ketol., (Copyright © 2023 The Author. Published by Elsevier Inc. All rights reserved.)

Objective: To investigate the association of accelerometer-measured lifestyle physical activity with rapid-rate non-sustained ventricular tachycardias (RR-NSVTs) in patients with arrhythmogenic cardiomyopathy (AC)., Methods: This multicentre, observational study enrolled 72 patients with AC, including right, left and biventricular forms of the disease, with underlying desmosomal and non-desmosomal mutations. Lifestyle physical activity, objectively monitored with accelerometers (ie, movement sensors) and RR-NSVT, identified as >188 bpm and >18 beats from a textile Holter ECG for 30 days., Results: Sixty-three patients with AC (38±17.6 years, 57% men) were included. A total of 17 patients experienced ≥1 RR-NSVTs, and a total of 35 events were recorded. The odds of occurrence of ≥1 RR-NSVT during the recording did not increase as a function of either total physical activity (OR 0.95, 95% CI (CI 95% ) 0.68 to 1.30 for 60 min increase) or moderate-to-vigorous activities (OR 0.89, CI 95% 0.71 to 1.08 for 5 min increase). Participants presenting RR-NSVTs during the recording (n=17) did not present greater odds of RR-NSVT in the days with more time either in total physical activity (OR 1.05, CI 95% 0.84 to 1.29 for additional 60 min) or moderate-to-vigorous activities (OR 1.05, CI 95% 0.97 to 1.12 for additional 5 min). Physical activity levels were neither different between the patients with and without RR-NSVTs during the recording period nor in the days of occurrence of RR-NSVT compared with the rest of the days. Finally, 4 of the 35 RR-NSVTs recorded in the 30 days occurred during physical activity (3 during moderate-to-vigorous intensity and 1 during light-intensity activities)., Conclusions: These findings suggest that lifestyle physical activity is not associated with RR-NSVTs in patients with AC., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

The trapping of the elusive vinylogous position of a vinyl carbene with an aliphatic C(sp 3 )-H bond has been achieved for the first time during a silver-catalyzed carbene/alkyne metathesis (CAM) process. A Tp x -containing silver complex first promotes the generation of a donor-acceptor silver carbene which triggers CAM, generating a subsequent donor-donor vinyl silver carbene species, which then undergoes a selective vinylogous C(sp 3 )-H bond insertion, leading to the synthesis of a new family of benzoazepines. Density functional theory (DFT) calculations unveil the reaction mechanism, which allows proposing that the C-H bond insertion reaction takes place in a stepwise manner, with the hydrogen shift being the rate determining step., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Micelles generated upon dissolving surfactants in water can be employed as nanovessels for catalytic transformations, in the so-called micellar catalysis methodology. This review is focused on the use of micellar catalysis in the context of the catalytic functionalization of carbon-hydrogen bonds. The micelles accumulate catalyst and reactants in their inner volume in such a high local concentration that kinetics are favored. The consequence is that, in most cases, processes that in conventional organic solvents require high temperatures and long reaction times are achieved in milder conditions when micellar catalysis is employed., Competing Interests: The authors declare no competing financial interest., (© 2022 American Chemical Society.)

The direct oxidation of benzene into phenol using molecular oxygen at very mild temperatures can be promoted in the presence of the copper complex Tp Br3 Cu(NCMe) in the homogeneous phase in the presence of ascorbic acid as the source of protons and electrons. The stoichiometric nature, relative to copper, of this transformation prompted a thorough DFT study in order to understand the reaction pathway. As a result, the dinuclear species Tp Br3 Cu II (μ-O • )(μ-OH)Cu II Tp Br3 is proposed as the relevant structure which is responsible for activating the arene C-H bond leading to phenol formation., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Aims: Genotype and left ventricular scar on cardiac magnetic resonance (CMR) are increasingly recognized as risk markers for adverse outcomes in non-ischaemic dilated cardiomyopathy (DCM). We investigated the combined influence of genotype and late gadolinium enhancement (LGE) in assessing prognosis in a large cohort of patients with DCM., Methods and Results: Outcomes of 600 patients with DCM (53.3 ± 14.1 years, 66% male) who underwent clinical CMR and genetic testing were retrospectively analysed. The primary endpoints were end-stage heart failure (ESHF) and malignant ventricular arrhythmias (MVA). During a median follow-up of 2.7 years (interquartile range 1.3-4.9), 24 (4.00%) and 48 (8.00%) patients had ESHF and MVA, respectively. In total, 242 (40.3%) patients had pathogenic/likely pathogenic variants (positive genotype) and 151 (25.2%) had LGE. In survival analysis, positive LGE was associated with MVA and ESHF (both, p < 0.001) while positive genotype was associated with ESHF (p = 0.034) but not with MVA (p = 0.102). Classification of patients according to genotype (G+/G-) and LGE presence (L+/L-) revealed progressively increasing events across L-/G-, L-/G+, L+/G- and L+/G+ groups and resulted in optimized MVA and ESHF prediction (p < 0.001 and p = 0.001, respectively). Hazard ratios for MVA and ESHF in patients with either L+ or G+ compared with those with L-/G- were 4.71 (95% confidence interval: 2.11-10.50, p < 0.001) and 7.92 (95% confidence interval: 1.86-33.78, p < 0.001), respectively., Conclusion: Classification of patients with DCM according to genotype and LGE improves MVA and ESHF prediction. Scar assessment with CMR and genotyping should be considered to select patients for primary prevention implantable cardioverter-defibrillator placement., (© 2022 The Authors. European Journal of Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

Genetic variants that result in truncation in desmoplakin ( DSP ) are a known cause of arrhythmogenic cardiomyopathy (AC). In homozygous carriers, the combined involvement of skin and heart muscle is well defined, however, this is not the case in heterozygous carriers. The aim of this work is to describe cutaneous findings and analyze the molecular and ultrastructural cutaneous changes in this group of patients. Four women and eight men with a mean age of 48 ± 14 years were included. Eight met definitive criteria for AC, one was borderline and three were silent carriers. No relevant macroscopic changes in skin and hair were detected. However, significantly lower skin temperature (29.56 vs. 30.97 °C, p = 0.036) and higher transepidermal water loss (TEWL) (37.62 vs. 23.95 g m 2 h 1, p = 0.028) were observed compared to sex- and age-matched controls. Histopathology of the skin biopsy showed widening of intercellular spaces and acantholysis of keratinocytes in the spinous layer. Immunohistochemistry showed a strongly reduced expression of DSP in all samples. Trichogram showed regular nodules (thickening) compatible with pseudomonilethrix. Therefore, regardless of cardiac involvement, heterozygous patients with truncation-type variants in DSP have lower skin temperature and higher TEWL, constant microscopic skin involvement with specific patterns and pseudomonilethrix in the trichogram.

Throughout infection, plant-parasitic nematodes activate a complex host defense response that will regulate their development and aggressiveness. Oxylipins-lipophilic signaling molecules-are part of this complex, performing a fundamental role in regulating plant development and immunity. At the same time, the sedentary root-knot nematode Meloidogyne spp. secretes numerous effectors that play key roles during invasion and migration, supporting construction and maintenance of nematodes' feeding sites. Herein, comprehensive oxylipin profiling of tomato roots, performed using LC-MS/MS, indicated strong and early responses of many oxylipins following root-knot nematode infection. To identify genes that might respond to the lipidomic defense pathway mediated through oxylipins, RNA-Seq was performed by exposing Meloidogyne javanica second-stage juveniles to tomato protoplasts and the oxylipin 9-HOT, one of the early-induced oxylipins in tomato roots upon nematode infection. A total of 7512 differentially expressed genes were identified. To target putative effectors, we sought differentially expressed genes carrying a predicted secretion signal peptide. Among these, several were homologous with known effectors in other nematode species; other unknown, potentially secreted proteins may have a role as root-knot nematode effectors that are induced by plant lipid signals. These include effectors associated with distortion of the plant immune response or manipulating signal transduction mediated by lipid signals. Other effectors are implicated in cell wall degradation or ROS detoxification at the plant-nematode interface. Being an integral part of the plant's defense response, oxylipins might be placed as important signaling molecules underlying nematode parasitism.

We present a case of sarcomeric hypertrophy cardiomyopathy diagnosed in a child who had hypertrophy degree regression during adolescence, with no left ventricular dysfunction and no increase of the ventricular diameters. ( Level of Difficulty: Intermediate. )., (© 2020 The Authors.)