Estructura de financiamiento de las empresas chilenas aplicación del modelo de jerarquía

This article makes an analysis of the different variables that affect the financing structure of 40 Chilean companies listed on the Santiago Stock Exchange, between 2010 and 2013 Dynamic models use panel data for the analysis of financial variables and their relation to the generation of cash flows of the company. The results show the pecking order model does not apply, as companies that have higher free cash flows prefer to finance their projects with debt or equity is not met, reflecting that they prefer to borrow to take advantage of the tax benefit.Este artículo realiza un análisis, de las distintas variables que afectan a la estructura de financiamiento de 40 empresas chilenas listadas en la bolsa de valores de Santiago, entre los periodos 2010 y 2013. Se utilizan modelos dinámicos con datos de panel para el análisis de las variables financieras y su relación con la generación de flujos de fondos de la empresa. Los resultados muestran que el modelo de jerarquía no se cumple, ya que las empresas que poseen mayores flujos de caja libre prefieren financiar sus proyectos con deuda o capital, lo que refleja que éstas prefieren endeudarse, para aprovechar el beneficio de los escudos fiscales

Agricultural waste as a sustainable source for nanoparticle synthesis and their antimicrobial properties for food preservation

Traditional agriculture from cropping to harvesting is contributing to climate change by increasing global greenhouse emissions. Circular economy approaches and biorefinery technologies based on the reuse, recycling, and remanufacturing might result in the valorization of wastes that consequently would avoid environmental pollution. Nanoparticles synthesis using bio-waste such as stems, leaves, seeds, pulp, stubble, and bagasse is considered a green approach with low energy consumption, and low-cost production. Characteristics of raw materials influence the final application of nanoparticles in edible coatings, and films. Therefore, the preparation of nanoparticles based on cellulose, pectin, metal (titanium oxide, silver, zinc oxide), or silica are considered organic, inorganic, or hybrid nanocomposites, are resulted in several benefits including shelf-life extension and broad-spectrum antimicrobial properties by its capacity to encapsulate active compounds that greatly improve food preservation. For considering agro-waste-based nanoparticles in food, challenges in homogenization and synthesis, yield, and toxicity are mainly described. Therefore, this review examines the employment of agro-industrial waste for the development of sustainable nanoparticles and their synthesis methods (top-down and bottom-up). Moreover, it discusses their incorporation and role in active edible coatings and films by highlighting their bioactive properties, mechanisms of action, and applications in food group preservation

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Higher blood vessel density in comparison to the lymphatic vessels in oral squamous cell carcinoma

Artículo de publicación ISIIntroduction: Oral squamous cell carcinoma (OSCC) is characterized by local invasion and the development of cervical metastasis. In the tongue, an association between the invasion of the lymphatic vessels and the development of metastasis in the regional lymph nodes has been demonstrated. Moreover, invasion of the blood vessels is associated with greater recurrence and poorer prognoses. Therefore, the presence and density of lymphatic and blood vessels in intra- and peritumoral tissues should play an important role in the progression, dissemination and metastasis of carcinomas. However, the evidence regarding OSCC is inconclusive. The aim of this study was to determine the comparison and association between the lymphatic (D2-40) and blood vessel (CD34) densities in intratumoral OSCC tissue. Materials and Methods: Thirty-seven cases diagnosed as OSCC between the years 2000 and 2008 were obtained from the Anatomic Pathology Service of the School of Dentistry, University of Chile. The immunohistochemical markers D2-40 and CD34 were used, and the densities (mm2) of lymphatic vessels (LVD) and blood vessels (BVD) in the intratumoral region were determined. The relationship between LVD and BVD values was evaluated. Results: There were significant association between the CD34 and D2-40 expression (rho=0.4, P<0.05) and between the LVD and the location in the tongue (P=0.019). The BVD was greater (128.0 vessels/mm2) than the LVD (42.9 vessels/mm2), and there was a positive correlation between the LVD and BVD. Conclusions: In OSCC, the BVD is greater than the LVD, and there is a moderate correlation between the two quantities.Fondecyt Grant 1120248 FONDEF NaD11/1096 D11I1096 FONDECYT 115102

Extracellular α-synuclein alters synaptic transmission in brain neurons by perforating the neuronal plasma membrane

It has been postulated that the accumulation of extracellular α-synuclein (α-syn) might alter the neuronal membrane by formation of 'pore-like structures' that will lead to alterations in ionic homeostasis. However, this has never been demonstrated to occur in brain neuronal plasma membranes. In this study, we show that α-syn oligomers rapidly associate with hippocampal membranes in a punctate fashion, resulting in increased membrane conductance (5 fold over control) and the influx of both calcium and a fluorescent glucose analogue. The enhancement in intracellular calcium (1.7 fold over control) caused a large increase in the frequency of synaptic transmission (2.5 fold over control), calcium transients (3 fold over control), and synaptic vesicle release. Both primary hippocampal and dissociated nigral neurons showed rapid increases in membrane conductance by α-syn oligomers. In addition, we show here that α-syn caused synaptotoxic failure associated with a decrease in SV2, a membrane protein of synaptic vesicles associated with neurotransmitter release. In conclusion, extracellular α-syn oligomers facilitate the perforation of the neuronal plasma membrane, thus explaining, in part, the synaptotoxicity observed in neurodegenerative diseases characterized by its extracellular accumulation. We propose that α-synuclein (α-syn) oligomers form pore-like structures in the plasma membrane of neurons from central nervous system (CNS). We believe that extracellular α-syn oligomers facilitate the formation of α-syn membrane pore-like structures, thus explaining, in part, the synaptotoxicity observed in neurodegenerative diseases characterized by its extracellular accumulation. We think that alterations in ionic homeostasis and synaptic vesicular depletion are key steps that lead to synaptotoxicity promoted by α -syn membrane pore-like structures.C. R. Pacheco funded by Ph.D. fellowship from CONICYT and FEBS Scholarship. This work was supported by grant Anillo-PBCT ACT-04 from the Chilean Government (LGA, CO), FONDECYT grant No. 1100502 (LGA, CO), FONDECYT grant No. 1140473 (LGA) and Spanish Ministerio de Economía y Competitividad (FIS PI10/00587; ISCIII-RETIC RED HERACLES RD06/0009/002-FEDER), and La Marató de TV3 (No. 100310). The Florey Institute of Neuroscience and Mental Health acknowledges the strong support from the Victorian Government and in particular the funding from the Operational Infrastructure Support Grant

Prevention of doxorubicin-induced cardiotoxicity by pharmacological non-hypoxic myocardial preconditioning based on Docosahexaenoic Acid (DHA) and carvedilol direct antioxidant effects: Study protocol for a pilot, randomized, double-blind, controlled trial (CarDHA trial)

Background Anthracycline-induced cardiotoxicity (AIC), a condition associated with multiple mechanisms of damage, including oxidative stress, has been associated with poor clinical outcomes. Carvedilol, a beta-blocker with unique antioxidant properties, emerged as a strategy to prevent AIC, but recent trials question its effectiveness. Some evidence suggests that the antioxidant, not the beta-blocker effect, could prevent related cardiotoxicity. However, carvedilol's antioxidant effects are probably not enough to prevent cardiotoxicity manifestations in certain cases. We hypothesize that breast cancer patients taking carvedilol as well as a non-hypoxic myocardial preconditioning based on docosahexaenoic acid (DHA), an enhancer of cardiac endogenous antioxidant capacity, will develop less subclinical cardiotoxicity manifestations than patients randomized to double placebo. Methods/design We designed a pilot, randomized controlled, two-arm clinical trial with 32 patients to evaluate the effects of non-hypoxic cardiac preconditioning (DHA) plus carvedilol on subclinical cardiotoxicity in breast cancer patients undergoing anthracycline treatment. The trial includes four co-primary endpoints: changes in left ventricular ejection fraction (LVEF) determined by cardiac magnetic resonance (CMR); changes in global longitudinal strain (GLS) determined by two-dimensional echocardiography (ECHO); elevation in serum biomarkers (hs-cTnT and NT-ProBNP); and one electrocardiographic variable (QTc interval). Secondary endpoints include other imaging, biomarkers and the occurrence of major adverse cardiac events during follow-up. The enrollment and follow-up for clinical outcomes is ongoing. Discussion We expect a group of anthracycline-treated breast cancer patients exposed to carvedilol and non-hypoxic myocardial preconditioning with DHA to show less subclinical cardiotoxicity manifestations than a comparable group exposed to placebo.Comisión Nacional de Investigación Científica y Tecnológica (CONICYT

<em>VNN1</em> Gene Expression Levels and the G-137T Polymorphism Are Associated with HDL-C Levels in Mexican Prepubertal Children

<div><h3>Background</h3><p><em>VNN1</em> gene expression levels and the G-137T polymorphism have been associated with high density lipoprotein cholesterol (HDL-C) levels in Mexican American adults. We aim to evaluate the contribution of <em>VNN1</em> gene expression and the G-137T variant to HDL-C levels and other metabolic traits in Mexican prepubertal children.</p> <h3>Methodology/Principal Findings</h3><p><em>VNN1</em> mRNA expression levels were quantified in peripheral blood leukocytes from 224 unrelated Mexican-Mestizo children aged 6–8 years (107 boys and 117 girls) and were genotyped for the G-137T variant (rs4897612). To account for population stratification, a panel of 10 ancestry informative markers was analyzed. After adjustment for admixture, the TT genotype was significantly associated with lower <em>VNN1</em> mRNA expression levels (<em>P</em> = 2.9 × 10⁻⁵), decreased HDL-C levels (β = −6.19, <em>P</em> = 0.028) and with higher body mass index (BMI) z-score (β = 0.48, <em>P</em> = 0.024) in the total sample. In addition, <em>VNN1</em> expression showed a positive correlation with HDL-C levels (r = 0.220; <em>P</em> = 0.017) and a negative correlation with BMI z-score (r = −0.225; <em>P</em> = 0.015) only in girls.</p> <h3>Conclusion/Significance</h3><p>Our data suggest that <em>VNN1</em> gene expression and the G-137T variant are associated with HDL-C levels in Mexican children, particularly in prepubertal girls.</p> </div

Comunidades digitales, museos e historia pública : experiencias en torno a América Latina

Los profundos cambios en la interacción social, en los postulados y límites de la acción estatal, en la distribución de las riquezas y pobrezas, y, en general, en la experiencia de la cotidianidad producidos desde 2020 por la pandemia del COVID-19 hacen necesarias reflexiones interdisciplinarias y lecturas comparadas para entender lo que estamos viviendo y arriesgar ideas sobre el porvenir. Este momento histórico nos ubica en un punto de observación privilegiado para evaluar y proyectar nuevos modos de organización y comunicación colectiva que, entre otras cosas, implican diferentes formas de relacionarnos con los pasados, con el valor que les atribuimos, con la forma como los conservamos y exhibimos, con los usos que les damos y, en general, con el tipo de relaciones que componemos a partir de ellos. En este contexto, diversas prácticas disciplinares han adoptado enfoques, metodologías y modos de codificación novedosos para mantenerse al tanto de lo que dichos cambios implican. Las humanidades digitales atraviesan un momento de auge y, consecuentemente, sus objetos de reflexión, fuentes de consulta y modos de transmitir conclusiones proponen nuevos horizontes de trabajo. Por otra parte, cada vez son más los museos latinoamericanos que han desarrollado iniciativas, programas y enfoques dedicados a promover la relectura de sus colecciones y la participación e inclusión de sujetos, públicos y audiencias. Finalmente, la historia pública poco a poco ha encontrado un momento de consolidación a través de la explosión de un sinfín de proyectos creativos que retan las formas tradicionales de apropiación del pasado