Expanding the stdpopsim species catalog, and lessons learned for realistic genome simulations.

Simulation is a key tool in population genetics for both methods development and empirical research, but producing simulations that recapitulate the main features of genomic datasets remains a major obstacle. Today, more realistic simulations are possible thanks to large increases in the quantity and quality of available genetic data, and the sophistication of inference and simulation software. However, implementing these simulations still requires substantial time and specialized knowledge. These challenges are especially pronounced for simulating genomes for species that are not well-studied, since it is not always clear what information is required to produce simulations with a level of realism sufficient to confidently answer a given question. The community-developed framework stdpopsim seeks to lower this barrier by facilitating the simulation of complex population genetic models using up-to-date information. The initial version of stdpopsim focused on establishing this framework using six well-characterized model species (Adrion et al., 2020). Here, we report on major improvements made in the new release of stdpopsim (version 0.2), which includes a significant expansion of the species catalog and substantial additions to simulation capabilities. Features added to improve the realism of the simulated genomes include non-crossover recombination and provision of species-specific genomic annotations. Through community-driven efforts, we expanded the number of species in the catalog more than threefold and broadened coverage across the tree of life. During the process of expanding the catalog, we have identified common sticking points and developed the best practices for setting up genome-scale simulations. We describe the input data required for generating a realistic simulation, suggest good practices for obtaining the relevant information from the literature, and discuss common pitfalls and major considerations. These improvements to stdpopsim aim to further promote the use of realistic whole-genome population genetic simulations, especially in non-model organisms, making them available, transparent, and accessible to everyone.

Pleomorphic adenoma of the palate: two cases report and literature review / Adenoma pleomorfo palatino: reporte de 2 casos y revisión de la literatura

Pleomorphic adenoma (PA) is the most common neoplasm encountered in major and minor salivary glands. Intraorally, it is most frequently developed in the palatal glands. Histologically, it is characterized by a diverse architecture comprised of epithelial stromal elements mixed with mucoid, myxoid, or chondroid fibrohyaline. A PA does not generally present gender bias and can occur at any age with the same clinical behavior. It is usually a round, slow-growing, painless tumor, which is firm upon palpation. We reported two cases of adult patients who were treated using transoral resection at San Juan de Dios Hospital in La Serena.

El Adenoma Pleomorfo es la neoplasia más común de las glándulas salivales mayores y menores. Intraoralmente las glándulas del paladar son las más afectadas. Histológicamente se caracteriza por una arquitectura variada que comprende elementos epiteliales mezclados con estroma mucoide, mixoide, fibrohialino o condroide, Los AP no suelen presentar predisposición por sexos, pudiendo aparecer a cualquier edad, con el mismo comportamiento clínico. Se presentan habitualmente como una tumoración redondeada de crecimiento lento, indolora y firme a la palpación. Presentamos dos casos de pacientes adultos, quienes fueron tratados mediante resección transoral en el hospital de la Serena.

Pilomatrixoma en la región preauricular: caso clínico / Pilomatrixoma in preauricular region: case report

El Pilomatrixoma o epitelioma calcificado de Malherbe es un tumor benigno derivado de los folículos pilosos. Afecta con más frecuencia a niños y adultos jóvenes. Ellos son nódulos dérmicos o subcutáneos que se presentan normalmente en forma asintomática, solitarios, con una consistencia firme o dura y no adheridos a planos profundos. Reportamos un caso de una niña con un pilomatrixoma en la región preauricular.

Pilomatrixoma or calcifying epithelioma of Malherbe is a benign tumor derived from hair follicles. Frequently found in children and young adults. They are usually asymptomatic, solitary, firm or hard, freely mobile, dermal or subcutaneous nodules. We present a case of a girl with a pilomatrixoma in preauricular region.

Hernia de Amyand: reporte y revisión de la literatura / Amyand hernia: acase report and review of the literature

La presencia de apendicitis aguda en una hernia inguinal es un hecho infrecuente, con un 0,13 por ciento de los casos. Esta rara condición se conoce como Hernia de Amyand. La forma de presentación habitual es la de una hernia inguinal complicada. Es por este motivo que el diagnóstico preoperatorio de apendicitis requiere de una alta sospecha clínica, realizándose mayoritariamente durante la cirugía. El estudio de imágenes, en particular la tomografía axial computada, han sido utilizados para confirmar este diagnóstico. El tratamiento recomendado es la apendicectomía y la reparación primaria de la hernia en el mismo tiempo operatorio. No se debe utilizar prótesis por el riesgo de infección y fístula de muñón apendicular. Debido a lo excepcional de esta patología, presentamos el caso de un hombre de 75 años que se manifestó como una hernia inguinal complicada y cuyo diagnóstico se realizó en pabellón luego de abrir el saco.

[Results of intraventricular resynchronization in patients with severe cardiac failure]. / Resultados clínicos de la resincronización ventricular en pacientes con insuficiencia cardíaca severa.

BACKGROUND: Intraventricular resynchronization with pacemakers is a promising therapy for patients with refractory cardiac failure and intraventricular conductions delay. However its long term effects are not well known. AIM: To report the results of this therapy in patients with cardiac failure. PATIENTS AND METHODS: Fourteen patients (11 male), whose mean age was 68 years, with a severe and refractory cardiac failure, have been treated in our unit using intraventricular resynchronization with pacemakers. Eight had a coronary heart disease and six a dilated myocardiopathy. The pacemaker was implanted transvenously, with conventional stimulation in atrium and right ventricle. The left ventricle was stimulated through an epicardial vein, accessed through the coronary sinus. RESULTS: In one patient the high thresholds did not allow a left ventricular stimulation. In the other 13 patients, a clinical improvement was observed in 11 (85%), that has been sustained for a mean of 8.2 months. The ejection fraction improved form 23.5 to 32.4% (p < 0.001), the 6 min walking test improved from 347 to 437 m (p = 0.003) and the functional capacity changes from 3.3 to 2.7 (p < 0.001). Three patients died during follow up. One was the patient in whom the stimulation failed and two had a sudden death. No complications of the procedure were observed. CONCLUSIONS: In this series, intraventricular resynchronization with pacemakers was effective in 11 of 13 patients, improving functional capacity and ejection fraction. Sudden death could be avoided adding a defibrillator to the pacemaker system.

[Focal atrial fibrillation. Clinical characteristic and results of radiofrequency ablation]. / Fibrilación auricular focal. Características clínicas y resultado de la ablación con radiofrecuencia.

BACKGROUND: Atrial fibrillation can originate in arrhythmogenic foci coming from the pulmonary veins. Patients with atrial fibrillation, initiated from triggering foci, can be treated with radiofrequency ablation. AIM: To report the results of radiofrequency ablation in patients with focal atrial fibrillation. PATIENTS AND METHODS: Thirteen patients with focal atrial fibrillation (8 male, aged 19 to 60 years old) are reported. Twelve had frequent crises refractory to antiarrhythmic drugs. Two had also flutter and tachycardia. One had a permanent atrial fibrillation lasting five years. Two had ventricular dysfunction and left atrial dilatation. The triggering focus was identified during the electrophysiological study, by the precocity of the potential that initiated the atrial fibrillation. RESULTS: All patients had early atrial extrasystolic beats, isolated or repetitives, that preceded atrial fibrillation. During the electrophysiological study, 18 foci (3 in the right and 15 in the left atrium all in pulmonary veins) were identified. Radiofrequency ablation had immediate success in 11 patients. In 5, a flutter was also ablated. One patient had a sinus dysfunction after the procedure and atrial fibrillation was not eliminated. In this and other patient in whom the procedure failed, a pacemaker was implanted and the atrioventricular node was blocked. In a follow up, ranging from 4 to 31 months, eight patients are asymptomatic and 3 recidivated. No complications have been detected. CONCLUSIONS: Patients with focal atrial fibrillation have common clinical and electrocardiographic features. Radiofrequency ablation of the triggering focus is possible and effective in most cases.