Figure-8 Tachycardia Confined to the Anterior Wall of the Left Atrium

Incisional atrial tachycardias have been described most frequently in patients with previous corrective surgery for congenital heart defects and mitral valve disease. Less information is available on atrial tachycardias appearing late after isolated aortic valve surgery. We report the case of a patient who developed a left figure-8 tachycardia after undergoing aortic valve replacement. During electrophysiologic study the entire cycle length of the tachycardia was mapped within a low voltage area confined to the left anterior atrial wall. However, during ablation a transmural lesion could not be attained. The mapping and ablation strategy along with the mechanism of the tachycardia are discussed

The Tie between Action and Language Is in Our Imagination

In this thesis, the embodied cognition proposal that action words are directly and automatically mapped into the perceiver\u2019s sensorimotor system, and understood via motor simulation, has been put under the lenses of neuropsychology, psychophysics, transcranial magnetic stimulation (TMS), and functional magnetic resonance imaging (fMRI) investigation. The objective was to establish whether the tie between language understanding and motor simulation is necessary for the former to be effective, to the extent that a virtual identity can be recognized between action and language systems..

THE OUTCOMES OF THE PRETERM NEWBORN AFFECTED BY CHORIOAMNIONITIS

Universitatea de Stat de Medicină şi Farmacie „Nicolae Testemiţanu”, Chişinău, Republica MoldovaIntroducere. Corioamnionita este una din cele mai frecvente cauze ale nașterii premature, care poate afecta intrauterin practic toate organele fătului. Mecanismele implicate sunt foarte complexe și tot mai mult discutate, inflamația „sterilă” pare să fie mai frecventă și mai susținută de dovezile științifice. Scopul lucrării. Aprecierea ratei hemoculturilor pozitive și a celor negative la nou-născuții prematuri mai mici de 34 săptămâni de gestație afectați de corioamnionită și complicațiile apărute la acest grup de copii. Material și metode. Pentru realizarea scopului a fost realizat un studiu observațional, descriptiv, pe un lot de 379 de copii nou-născuți prematur, cu termenul < 34 săptămâni de gestație, în Centrul Perinatal de nivel terțiar IMC, unicul din țară, în perioada anului 2022. Rezultatele au fost analizate utilizând metodele statistice. Rezultate. În urma analizei lotului de studiu s-a depistat ca 8% din subiecți au avut hemoculturile pozitive la naștere, fiind implicate Klebsiella pneumoniae, St. epidermidis, E. coli, Str. beta-hemolitic grup B, în timp ce la restul 92% nu s-au depistat germeni patogeni în hemocultură. Printre complicațiile cele mai frecvent depistate sunt: sepsisul neonatal precoce, pneumonia, sindromul de detresă respiratorie prin deficit de surfactant, displazia bronhopulmonară, hemoragia intraventriculară, enterocolita ulcero-necrotică. Concluzii. Corioamnionita are efect negativ larg asupra dezvoltării fătului și nou-născutului, chiar până la deces. Aprofundarea cunoștințelor despre mecanismele patofiziologice ale corioamnionitei va ajuta la elaborarea unui management clinic orientat spre îmbunătățirea rezultatului neonatal la nou-născuții prematuri.Background. Chorioamnionitis is one of the most common causes of preterm birth, which intrauterine can affect the development of all organs. The mechanisms involved are very complex with increasingly interest for science. „Sterile” inflammation appears to be more common and supported by scientific evidence. Objective of the study. Evaluation of the rate of positive and negative blood cultures in preterm new-borns less than 34 weeks of gestation affected by chorioamnionitis and the complications occurring in this group of children. Material and methods. To achieve the goal, we follow a group of 379 preterm new-borns, with a term < 34 weeks of gestation, born in the IMC, III rd level Perinatal Centre, the only one in the country, during the year 2022. The results will be analysed using statistical methods. Results. Analysing this group, it was found that 8% of the subjects had positive blood cultures at birth, being involved Klebsiella pneumoniae, St. epidermidis, E. coli, Str. beta-haemolytic group B, while in the others 92% no pathogenic germs were detected in the blood culture. Among the most frequently detected outcomes are: early neonatal sepsis, pneumonia, surfactant deficiency respiratory distress syndrome, bronchopulmonary dysplasia, intraventricular haemorrhage, necrotic ulcerative enterocolitis. Conclusion. Chorioamnionitis has a wide negative effect on the development of the foetus and the new-born, leading to death. Improvement of the knowledge about the pathophysiological mechanisms of chorioamnionitis will help to develop a clinical management aimed to improve the neonatal outcome in premature new-borns

Hematopoietic stem and progenitor cells and potentials for application in fetal cell replacement therapy

Fetal cell replacement therapy or in utero hematopoietic cell transplantation (IUHCT) is proposed as a non-myeloablative alternative to bone marrow transplantation (BMT) for a number of inborn immunologic, hematologic and metabolic disorders. IUHCT represents the method through which variable amounts of natural or genetically modified hematopoietic cells can be transferred to the fetal recipient in hope of correcting the disorder and preventing postnatal permanent organ damage. Although proof-of-principle has been achieved by succesful correction of X linked severe combined immune deficiency (X-SCID), in the majority of target diseases treated with IUHCT engraftment was insufficient for clinical benefit. Thus, the therapeutical promise of IUHCT remains unfullfilled and many challenges stand. In the present thesis we investigate the optimal cell population for IUHCT by first identifying a novel commitment/differentiation step of hematopoietic stem cells (HSCs) in adult murine hematopoiesis and then evaluating the therapeutical potential of the lymphoid primed multipotent progenitors (LMPPs) for immune reconstitution in a model of fetal X-SCID transplantation. We find that LMPPs generate rapid and sustained lymphoid reconstitution with polyclonal T cells, but that HSCs are most likely required for long term engraftment. We also find that the fetal microenvironment is apparently more receptive to donor HSCs (but also LMPPs) as it allows higher levels of chimerism after IUHCT then after BMT in neonatal or adult age. In the last part we investigate in adult and fetal animal models the proposed plasticity of HSCs, a feature that holds promise for clinical BMT (or IUHCT) to non-hematopoietic disorders. We find that HSCs plasticity is a result of heterotypic cell fusion, probably induced by inflammation/injury in the target tissue. We also show that heterotypic cell fusion is not a physiological frequently occuring event during development and we demonstrate that not only myeloid, but also lymphoid cells are efficient fusogenic partners to non-hematopoietic tissues

Remote refocusing light-sheet fluorescence microscopy for high-speed 2D and 3D imaging of calcium dynamics in cardiomyocytes

The high prevalence and poor prognosis of heart failure are two key drivers for research into cardiac electrophysiology and regeneration. Dyssynchrony in calcium release and loss of structural organization within individual cardiomyocytes (CM) has been linked to reduced contractile strength and arrhythmia. Correlating calcium dynamics and cell microstructure requires multidimensional imaging with high spatiotemporal resolution. In light-sheet fluorescence microscopy (LSFM), selective plane illumination enables fast optically sectioned imaging with lower phototoxicity, making it suitable for imaging subcellular dynamics. In this work, a custom remote refocusing LSFM system is applied to studying calcium dynamics in isolated CM, cardiac cell cultures and tissue slices. The spatial resolution of the LSFM system was modelled and experimentally characterized. Simulation of the illumination path in Zemax was used to estimate the light-sheet beam waist and confocal parameter. Automated MATLAB-based image analysis was used to quantify the optical sectioning and the 3D point spread function using Gaussian fitting of bead image intensity distributions. The results demonstrated improved and more uniform axial resolution and optical sectioning with the tighter focused beam used for axially swept light-sheet microscopy. High-speed dual-channel LSFM was used for 2D imaging of calcium dynamics in correlation with the t-tubule structure in left and right ventricle cardiomyocytes at 395 fps. The high spatio-temporal resolution enabled the characterization of calcium sparks. The use of para-nitro-blebbistatin (NBleb), a non-phototoxic, low fluorescence contraction uncoupler, allowed 2D-mapping of the spatial dyssynchrony of calcium transient development across the cell. Finally, aberration-free remote refocusing was used for high-speed volumetric imaging of calcium dynamics in human induced pluripotent stem-cell derived cardiomyocytes (hiPSC-CM) and their co-culture with adult-CM. 3D-imaging at up to 8 Hz demonstrated the synchronization of calcium transients in co-culture, with increased coupling with longer co-culture duration, uninhibited by motion uncoupling with NBleb.Open Acces

¿Discriminas o te discriminan?: un análisis de las percepciones de universitarios de cuatro ciudades del Perú

Este texto analiza las percepciones de estudiantes –de carreras relacionadas con los negocios, de universidades privadas y nacionales de Arequipa, Huancayo, Lima, y Trujillo–, sobre la discriminación dentro de sus instituciones académicas y sobre los factores considerados relevantes para acceder con éxito al mercado laboral. Se aplicaron tres herramientas metodológicas a diversas muestras no probabilísticas de ocho universidades (la mitad privadas) y a un número total de 1.919 estudiantes de ambos sexos: metodología Q, encuestas y grupos focales. Encontramos que los jóvenes de las universidades privadas y nacionales manifiestan bastante optimismo respecto al cumplimiento de sus metas laborales. Sin embargo, cerca de dos tercios de jóvenes de universidades nacionales buscarían migrar al extranjero en busca de trabajo, y un tercio de los de las universidades privadas. Asimismo, el 50% de los estudiantes de ambos tipos de universidades señalan percibir alguna forma de discriminación en sus centros de estudio; mientras 10% señalan realmente haber sido víctimas de dicha discriminación por su situación económica, sexo, raza, lugar de procedencia, lengua u orientación sexual; y un 28% indican haber sido discriminados por su apariencia física. La percepción de discriminación resulta ser más importante en universidades privadas que en las nacionales. A su vez, esta percepción de discriminación entre alumnos es mayor que la que se da respecto de la relación profesor-alumno. Finalmente, cabe resaltar que la brecha entre la percepción de existencia de discriminación y el reconocimiento de ser víctima de ella, parece deberse a que los estudiantes compensan los aspectos no valorados por la sociedad con el desarrollo de habilidades y capacidades, gestión de la apariencia corporal y laboriosidad

Holography in 7D Randall-Sundrum cosmology

We define the 7D Randall-Sundrum (RS) background and construct the corresponding 6D theory via AdS/CFT duality. In simple approximations, the Friedmann equation derived from 7D RS cosmology and the brane view-point results exactly match. Possible cosmologies on the bulk side are also outlined.Comment: 2 pages, 1 figure, talk given at the Cargese Summer School, May 22 - June 3, 200