Objetivo: Conocer el comportamiento epidemiológico y asociaciones de la FA en población mexicana. Material y métodos: Analizamos 8,686 pacientes de 38 cardiólogos inscritos en REMECAR, divididos por ...edad y sexo. Comorbilidades estudiadas: obesidad, ERC, HTA, DM, dislipidemia, EVC, EPOC, hipotiroidismo, IC y CI. Programa: IBM SPSS. Resultados: FA en 498 pacientes (5.7%), mayor prevalencia en hombres (6.1 vs. 5.3%), mayor edad en mujeres (74.3 ± 12.1 vs. 70.5 ± 12.3 años, p < 0.0001). En mujeres menores de 60 años la FA se asoció con IC (p = 0.041), en hombres con ERC (p = 0.43), DM (p = 0.009), EVC (p = 0.001), hipotiroidismo (p = 0.001) e IC (p = 0.001). En mujeres mayores de 60 años se asoció con ERC (p = 0.001), dislipidemia (p = 0.001), EVC (p = 0.001), EPOC (p = 0.001) e IC (p = 0.001), en hombres con ERC (p = 0.002), EVC (p = 0.001), EPOC (p = 0.002), hipotiroidismo (p = 0.002), IC (p = 0.001) y CI (p = 0.033). En mujeres la FA se asoció con 1.13 veces mayor probabilidad de obesidad, 1.13 de HTA, 2.8 de ERC, 2.9 de EPOC, 4.3 de EVC y 6.5 de IC, en hombres la FA se asoció con 1.05 veces mas probabilidad de HTA, 1.4 de DM, 2.1 de ERC, 2.4 de EPOC, 3 de hipotiroidismo, 4.7 de EVC y 6 de IC. Conclusiones: La FA es una arritmia muy frecuente, con mayor prevalencia en pacientes que acuden a consulta de cardiología, en hombres y mayor edad de presentación en las mujeres. A mayor edad, mayor prevalencia de FA y de comorbilidades, la IC es la condición más frecuente con la que se asoció la FA.
The oxidative phosphorylation system is one of the best-characterized metabolic pathways. In mammals, the protein components and X-ray structures are defined for all complexes except complex I. Here, ...we show that NDUFA4, formerly considered a constituent of NADH Dehydrogenase (CI), is instead a component of the cytochrome c oxidase (CIV). Deletion of NDUFA4 does not perturb CI. Rather, proteomic, genetic, evolutionary, and biochemical analyses reveal that NDUFA4 plays a role in CIV function and biogenesis. The change in the attribution of the NDUFA4 protein requires renaming of the gene and reconsideration of the structure of CIV. Furthermore, NDUFA4 should be considered a candidate gene for CIV rather than CI deficiencies in humans.
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► NDUFA4 physically interacts with complex IV and not with complex I ► Absence of NDUFA4 does not perturb CI but instead reduces CIV amount and activity ► NDUFA4 coevolved with complex IV and not with complex I
Acute tubular necrosis (ATN) caused by ischemia/reperfusion (I/R) during renal transplantation delays allograft function. Identification of factors that mediate protection and/or epithelium recovery ...could help to improve graft outcome. We studied the expression, regulation and role of hypoxia inducible factor 1-alpha (HIF-1 α), using in vitro and in vivo experimental models of I/R as well as human post-transplant renal biopsies. We found that HIF-1 α is stabilized in proximal tubule cells during ischemia and unexpectedly in late reperfusion, when oxygen tension is normal. Both inductions lead to gene expression in vitro and in vivo. In vitro interference of HIF-1 α promoted cell death and in vivo interference exacerbated tissue damage and renal dysfunction. In pos-transplant human biopsies, HIF-1 α was expressed only in proximal tubules which exhibited normal renal structure with a significant negative correlation with ATN grade. In summary, using experimental models and human biopsies, we identified a novel HIF-1 α induction during reperfusion with a potential critical role in renal transplant.
We investigated a diffusion-like equation with a bounded speed of signal propagation (the so called telegrapher’s equation) in a random media. We discuss some properties of the mean-value solution in ...a well-defined perturbation theory. The frequency-dependent effective-velocity of propagation is studied in the long and short time regime. We show that due to the wave-like character of telegrapher’s equation the effective-velocity is a complex dispersive function in time. Exact results and asymptotic perturbative long-time behaviors (for an exponential space-correlated binary disorder) are presented, showing their agreement and corroborating the goodness of the effective medium approximation in continuous system.
In a recent paper Cáceres MO, Comments on wave-like propagation with binary disorder. J. Stat. Phys. 2021;182(36):doi.org/10.1007/s10955-021-02699-0., the evolution of a wave-like front perturbed by ...space-correlated disorder was studied. In addition, the generic solution of the field mean-value was presented as a series expansion in Terwiel's cumulants operators. This infinite series cuts due to the algebra of naked Terwiel's cumulants when these cumulants are associated to a space exponential-correlated symmetric binary disorder. We apply an equivalent approach to study the dispersion-relation for 1D surface gravity waves propagating on an irregular floor. The theory is based on the study of the mean-value of plane-wave-like Fourier modes for the propagation and damping of surface waves on a random bottom.
The mammalian target of rapamycin (mTOR) pathway, which is essential for cell proliferation, is repressed in certain cell types in hypoxia. However, hypoxia-inducible factor 2α (HIF2α) can act as a ...proliferation-promoting factor in some biological settings. This paradoxical situation led us to study whether HIF2α has a specific effect on mTORC1 regulation. Here we show that activation of the HIF2α pathway increases mTORC1 activity by upregulating expression of the amino acid carrier SLC7A5. At the molecular level we also show that HIF2α binds to the Slc7a5 proximal promoter. Our findings identify a link between the oxygen-sensing HIF2α pathway and mTORC1 regulation, revealing the molecular basis of the tumor-promoting properties of HIF2α in von Hippel-Lindau-deficient cells. We also describe relevant physiological scenarios, including those that occur in liver and lung tissue, wherein HIF2α or low-oxygen tension drive mTORC1 activity and SLC7A5 expression.
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► HIF2α induces the expression of the amino acid carrier SLC7A5 ► HIF2α induces mTORC1 activity via SLC7A5 ► HIF2α induces tumor growth via SLC7A5 ► Hypoxia induces mTORC1 and SLC7A5 in the lung
The accuracy of 3D reconstructions of the craniomaxillofacial region using cone beam computed tomography (CBCT) is important for the morphological evaluation of specific anatomical structures. ...Moreover, an accurate segmentation process is fundamental for the physical reconstruction of the anatomy (3D printing) when a preliminary simulation of the therapy is required. In this regard, the objective of this study is to evaluate the accuracy of four different types of software for the semiautomatic segmentation of the mandibular jaw compared to manual segmentation, used as a gold standard. Twenty cone beam computed tomography (CBCT) with a manual approach (Mimics) and a semi-automatic approach (Invesalius, ITK-Snap, Dolphin 3D, Slicer 3D) were selected for the segmentation of the mandible in the present study. The accuracy of semi-automatic segmentation was evaluated: (1) by comparing the mandibular volumes obtained with semi-automatic 3D rendering and manual segmentation and (2) by deviation analysis between the two mandibular models. An analysis of variance (ANOVA) was used to evaluate differences in mandibular volumetric recordings and for a deviation analysis among the different software types used. Linear regression was also performed between manual and semi-automatic methods. No significant differences were found in the total volumes among the obtained 3D mandibular models (Mimics = 40.85 cm
, ITK-Snap = 40.81 cm
, Invesalius = 40.04 cm
, Dolphin 3D = 42.03 cm
, Slicer 3D = 40.58 cm
). High correlations were found between the semi-automatic segmentation and manual segmentation approach, with R coefficients ranging from 0,960 to 0,992. According to the deviation analysis, the mandibular models obtained with ITK-Snap showed the highest matching percentage (Tolerance A = 88.44%, Tolerance B = 97.30%), while those obtained with Dolphin 3D showed the lowest matching percentage (Tolerance A = 60.01%, Tolerance B = 87.76%) (
< 0.05). Colour-coded maps showed that the area of greatest mismatch between semi-automatic and manual segmentation was the condylar region and the region proximate to the dental roots. Despite the fact that the semi-automatic segmentation of the mandible showed, in general, high reliability and high correlation with the manual segmentation, caution should be taken when evaluating the morphological and dimensional characteristics of the condyles either on CBCT-derived digital models or physical models (3D printing).
In a recent paper (J Stat Phys 179:729–747, 2020) time evolution of the telegrapher’s equation subjected to a random velocity field was studied in the context of the effective medium approximation. ...In addition, the solution for the mean-value of the field was presented as a series expansion in Terwiel’s cumulants. Here we have proved that this expansion cuts if the random velocity field is emulated with a stationary exponential-correlated symmetric binary disorder. The present conclusion can also be used to tackle other wave-like models of propagation with Markovian binary disorder.
Las Unidades de Producción Familiar (UPF) están conformadas por capitales natural, físico, financiero, humano y social. Los dos últimos constituyen la base del funcionamiento del resto y de la unidad ...de producción. En México, Chiapas y la Frailesca, la producción de maíces, particularmente de maíces locales, tiene valor cultural, agronómico y económico. El objetivo de esta investigación fue caracterizar las Unidades de Producción Familiar que cultivan maíces locales en la región Frailesca del estado de Chiapas, sobre la base cultural del manejo de los capitales humano y social. Se estudiaron 80 UPF de 20 comunidades seleccionadas mediante un muestreo por redes. Se utilizó el enfoque Modos de Vida Sustentable como marco de referencia. Se aplicaron entrevistas semiestructuradas y se realizaron observaciones participantes. En el estudio predominaron las familias nucleares con líderes de edad avanzada. Los jóvenes no priorizan la conservación de los maíces locales sino actividades más rentables como la ganadería, los maíces híbridos y el café. Existe un excesivo uso de agroquímicos que afecta los recursos suelo, agua y biodiversidad. Se distinguieron 6 tipos de UPF de acuerdo con sus capitales humano y social. El grupo 3 (G3) mostró un mejor equilibrio entre ambos por la participación familiar, destacándose entre los de mayor experiencia en el cultivo de maíces locales y por tener relaciones locales y de cooperación más sólidas. Se concluye que las UPF presentan características que contribuyen o afectan la conservación de los maíces locales, como la continuidad generacional, el deterioro de los recursos naturales que sostienen el cultivo a través de la fusión de las prácticas tradicionales con las modernas y la dependencia de recursos externos.
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