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Validation of an early vascular aging construct model for comprehensive cardiovascular risk assessment using external risk indicators for improved clinical utility: data from the EVasCu study
No full textBackground: Cardiovascular diseases (CVDs) remain a major global health concern, necessitating advanced risk assessment beyond traditional factors. Early vascular aging (EVA), characterized by accelerated vascular changes, has gained importance in cardiovascular risk assessment. Methods: The EVasCu study in Spain examined 390 healthy participants using noninvasive measurements. A construct of four variables (Pulse Pressure, Pulse Wave Velocity, Glycated Hemoglobin, Advanced Glycation End Products) was used for clustering. K-means clustering with principal component analysis revealed two clusters, healthy vascular aging (HVA) and early vascular aging (EVA). External validation variables included sociodemographic, adiposity, glycemic, inflammatory, lipid profile, vascular, and blood pressure factors. Results: EVA cluster participants were older and exhibited higher adiposity, poorer glycemic control, dyslipidemia, altered vascular properties, and higher blood pressure. Significant differences were observed for age, smoking status, body mass index, waist circumference, fat percentage, glucose, insulin, C-reactive protein, diabetes prevalence, lipid profiles, arterial stiffness, and blood pressure levels. These findings demonstrate the association between traditional cardiovascular risk factors and EVA. Conclusions: This study validates a clustering model for EVA and highlights its association with established risk factors. EVA assessment can be integrated into clinical practice, allowing early intervention and personalized cardiovascular risk management. © 2024, The Author(s).Ministerio de Ciencia, Innovación y Universidades, MCIU, (FPU19/06866); European Commission, EC; European Social Fund Plus, ESF; Universidad de Castilla-La Mancha, UCLM, (2023‐GRIN‐ 34459); European Regional Development Fund, ERDFUniversidad Autónoma de Chil
Scientific Production and h-Index of Chilean Specialists in Digestive Surgery
No full textThe Hirsch index (h-index) is recognized as an effective way to summarize, an individual’s scientific research output. However, a benchmark for evaluating surgeon scientists in the field of digestive surgery is still not available. The bibliometric evaluation was conducted on the Scopus Database on all active members joining the Chilean Surgical Society, specifically, digestive surgery specialists. Scientific production was analyzed by considering the number of total publications, number of total citations and h-index; the geographical data for each case was also recorded. The median h-index for the digestive surgeons was 2 (4.3±6.8; range, 0-40); 76.8% of digestive surgeons had at least one scientific journal indexed in Scopus. The 43 surgeons analyzed, jointly published a total of 1011 articles (minimum 1, maximum 434), which were cited 9424 times (range 0 to 5368 citations), with a Median of 30 citations. Additional, 62.5% of digestive surgeons are from the city of Santiago. Of the authors with a higher h-index 3, only two were not from Santiago. The difference in h-index between men and women was statistically significant. Bibliometric analysis of the scientific production in digestive surgery may facilitate the recognition of factors that may further enhance research activity and clinical performance, and be useful for a comparative assessment of authors or research groups in terms of quality and quantity of the scientific production
Epigenetic modulation of cytokine expression in gastric cancer: influence on angiogenesis, metastasis and chemoresistance
No full textCytokines are proteins that act in the immune response and inflammation and have been associated with the development of some types of cancer, such as gastric cancer (GC). GC is a malignant neoplasm that ranks fifth in incidence and third in cancer-related mortality worldwide, making it a major public health issue. Recent studies have focused on the role these cytokines may play in GC associated with angiogenesis, metastasis, and chemoresistance, which are key factors that can affect carcinogenesis and tumor progression, quality, and patient survival. These inflammatory mediators can be regulated by epigenetic modifications such as DNA methylation, histone protein modification, and non-coding RNA, which results in the silencing or overexpression of key genes in GC, presenting different targets of action, either direct or mediated by modifications in key genes of cytokine-related signaling pathways. This review seeks insight into the relationship between cytokine-associated epigenetic regulation and its potential effects on the different stages of development and chemoresistance in GC. Copyright © 2024 Reyes, Pulgar, Vivallo, Ili, Mora-Lagos and Brebi.National FONDECYT, (1210440, 3210629, ICN2021_045, ID21I10027
Reducing the overfitting in the gROC curve estimation
No full textThe generalized receiver-operating characteristic, gROC, curve considers the classification ability of diagnostic tests when both larger and lower values of the marker are associated with higher probabilities of being positive. Its empirical estimation implies to select the best classification subsets among those satisfying particular condition. Both strong and weak consistency have already been proved. However, using the same data for both to select the classification subsets and to calculate its gROC curve leads to an over-optimistic estimate of the real performance of the diagnostic criteria on future samples. In this work, the bias of the empirical gROC curve estimator is explored through Monte Carlo simulations. Besides, two cross-validation based algorithms are proposed for reducing the overfitting. The practical application of the proposed algorithms is illustrated through the analysis of a real-world dataset. Simulation results suggest that the empirical gROC curve estimator returns optimistic approximations, especially, in situations in which the diagnostic capacity of the marker is poor and the sample size is small. The new proposed algorithms improve the estimation of the actual diagnostic test accuracy, and get almost unbiased gAUCs in most of the considered scenarios. However, the cross-validation based algorithms reported larger L1-errors than the standard empirical estimators, and increment the computational cost of the procedures. As online supplementary material, this manuscript includes an R function which wraps up the implemented routines. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023.Ministerio de Ciencia e Innovación, MICIN
Role of the Fungus Pneumocystis in IL1β Pathway Activation and Airways Collagen Deposition in Elastase-Induced COPD Animals
No full textInflammation and mucus production are prevalent characteristics of chronic respiratory conditions, such as asthma and chronic chronic obstructive pulmonary disease (COPD). Biological co-factors, including bacteria, viruses, and fungi, may exacerbate these diseases by activating various pathways associated with airway diseases. An example is the fungus Pneumocystis, which is linked to severe COPD in human patients. Recent evidence has demonstrated that Pneumocystis significantly enhanced inflammation and mucus hypersecretion in a rat model of elastase-induced COPD. The present study specifically aims to investigate two additional aspects associated with the pathology induced by Pneumocystis infection: inflammation and collagen deposition around airways. To this end, the focus was to investigate the role of the IL-1β pro-inflammatory pathway during Pneumocystis infection in COPD rats. Several airway pathology-related features, such as inflammation, mucus hypersecretion, and fibrosis, were evaluated using histological and molecular techniques. COPD animals infected with Pneumocystis exhibited elevated inflammation levels, including a synergistic increase in IL-1β and Cox-2. Furthermore, protein levels of the IL-1β-dependent transcription factor cAMP response element-binding (CREB) showed a synergistic elevation of their phosphorylated version in the lungs of COPD animals infected with Pneumocystis, while mucus levels were notably higher in the airways of COPD-infected animals. Interestingly, a CREB responsive element (CRE) was identified in the Muc5b promoter. The presence of CREB in the Muc5b promoter was synergistically increased in COPD animals infected with Pneumocystis compared to other experimental groups. Finally, an increment of deposited collagen was identified surrounding the airways of COPD animals infected with Pneumocystis compared with the other experimental animal groups and correlated with the increase of Tgfβ1 mRNA levels. These findings emphasize the role of Pneumocystis as a potential biological co-factor in chronic respiratory diseases like COPD or asthma, warranting new perspectives in the treatment of chronic respiratory diseases. © 2024 by the authors.Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (11191121); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYTUniversidad Autónoma de Chil
Racism and food delivery platforms: shaping migrants’ work experiences and future expectations in the United Kingdom and Chile
No full textRecent studies have demonstrated that platform work is predominately undertaken by migrant workers. Drawing on a qualitative study of platform-based food delivery work in Chile and the United Kingdom, we examine how migrant workers’ experiences of race and ethnicity shape their working conditions and future job prospects in the platform economy. In both countries, migrants perceived platform work to be a way of avoiding forms of racism in the formal economy. However, while in the United Kingdom this type of work lived up to migrants’ expectations of providing an environment with fewer overt forms of racism, in Chile, workers experienced high levels of everyday racism when performing platform work. We argue that processes of racialisation have a direct impact on the labour conditions of workers in the gig economy, and that race and migration background play a key role in migrants’ labour trajectories. © 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Universidad Autónoma de Chil
Nervios olfatorio, trigémino, facial, glosofaríngeo y vago: vínculos con sars-cov-2 y prospectivas neurosemiológicas
No full textA brief review of olfactory, facial, glossopharyngeal and vagus nerves is presented, the first one functionally related to odoriferous chemosensory innervation in the nasal mucosa, the following four cranial nerves to endocranial headache and oropharyngeal mucosa for purposes of gustatory sensory transduction. These nerves are associated with symptoms in Covid-19 positive patients, which dysosmia, anosmia, dysgeusia, ageusia manifestation, among other neurosemiological characteristics. It is concluded that these semiological characteristics may be due to neurotropic and transynaptic mechanisms, therefore a more rigorous neurological examination should be performed on symptoms and signs of Covid-19 patients.Se presenta una breve revisión los nervios olfatorio, trigémino, facial, glosofaríngeo y vago, el primero funcionalmente relacionado con la inervación quimiosensitiva olfativa en la mucosa nasal, los siguientes para el registro de dolor endocraneal y para la mucosa orofaríngea, a efectos de transducción sensitiva gustativa. Estos nervios se vinculan con los síntomas en pacientes positivos para Covid-19, que manifiestan como dolor de cabeza, disosmia, anosmia, disgeusia, ageusia entre otras características neurosemiológicas. Se concluye que estas características semiológicas pueden deberse a mecanismos neurotrópicos y transinápticos por lo que se debe realizar un examen neurológico más riguroso sobre síntomas y signos de pacientes con Covid-19
Construction of professional identity in novel teachers. Learning experiences: help or hindrance?
No full textThis article offers the reader a socio-cultural examination of a series of fundamental processes related to the construction and development of the professional teaching identity. By way of illustration, we analyse 39 subjective learning experiences reported by 12 novice teachers in Chile. The objective is to examine aspects of their experiences that facilitated or hindered changes in their identity positions. Our results suggest that the processes involved in the construction and development of identity are closely linked to their assessments of certain specific aspects of their experiences. These include (i) the material and social conditions found in highly demanding work environments; (ii) certain socio-cultural characteristics such as vulnerability in educational contexts; (iii) personal learning trajectories; (iv) interactions with students or your own experiences as students; and (v) a series of other characteristics that are not part of the situation as such, but that nevertheless influence it, such as educational policy. © Instituto Universitário de Ciências Psicológicas, Sociais e da Vida 2024.Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1220081); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECY
N- acyl homoserine lactones (AHLs) type signal molecules produced by rhizobacteria associated with plants that growing in a metal(oids) contaminated soil: A catalyst for plant growth
No full textThe present study explores the potential of rhizobacteria isolated from Baccharis linearis and Solidago chilensis in metal(loid)-contaminated soil for producing N-acyl-homoserine lactones (AHLs)-type signal molecules and promoting plant growth. A total of 42 strains were isolated, four demonstrating the production of AHL-type signal molecules. Based on 16S rRNA gene sequencing analyses and MALDI-TOF analyses, these four isolates were identified as belonging to the Pseudomonas genus, specifically P. brassicacearum, P. frederickberguensis, P. koreensis, and P. orientalis. The four AHL-producing strains were evaluated for metal(loid)s tolerance, their plant growth promotion traits, AHL quantification, and their impact on in vitro Lactuca sativa plant growth. The study found that four strains exhibited high tolerance to metal(loid)s, particularly As, Cu, and Zn. Additionally, plant growth-promoting traits were detected in AHL-producing bacteria, such as siderophore production, ammonia production, ACC deaminase activity, and P solubilization. Notably, AHL production varied among strains isolated from B. linearis, where C7-HSL and C9-HSL signal molecules were detected, and S. chilensis, where only C7-HSL signal molecules were observed. In the presence of copper, the production of C7-HSL and C9-HSL significantly decreased in B. linearis isolates, while in S. chilensis isolates, C7-HSL production was inhibited. Further, when these strains were inoculated on lettuce seeds and in vitro plants, a significant increase in germination and plant growth was observed. Mainly, the inoculation of P. brassicacearum and P. frederickberguensis led to extensive root hair development, significantly increasing length and root dry weight. Our results demonstrate that rhizospheric strains produce AHL molecules and stimulate plant growth, primarily through root development. However, the presence of copper reduces the production of these molecules, potentially affecting the root development of non-metalloid tolerant plants such as S. chilensis, which would explain its low population in this hostile environment. © 2024 Elsevier GmbHScientific and Technological Bioresources Nucleus BIOREN; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (3210501); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT; Universidad de La Frontera, UFR
EVOLUCIÓN DE LAS POLÍTICAS DE DESARROLLO ECONÓMICO LOCAL EN CHILE 2007-2015: DESDE LA VISIÓN ASISTENCIALISTA A LA VISIÓN SISTÉMICA
No full textUtilizando la información contenida en las cuentas públicas del 20% de las municipalidades del país, se estudia la evolución en la ejecución de las políticas de desarrollo económico local para un conjunto de 48 municipalidades, entre los años 2007 y 2015. Los resultados indican que la importancia relativa de las políticas de empleo y capital humano se han reducido, las de emprendimiento se han mantenido, y las de fortalecimiento institucional y sistema productivo comunal se han incrementado. En esto, el rol de los programas y convenios entre las municipalidades y los organismos del gobierno central parecen haber jugado un rol clave.