The Telomere Capping Complex CST Has an Unusual Stoichiometry, Makes Multipartite Interaction with G-Tails, and Unfolds Higher-Order G-Tail Structures

The telomere-ending binding protein complex CST (Cdc13-Stn1-Ten1) mediates critical functions in both telomere protection and replication. We devised a co-expression and affinity purification strategy for isolating large quantities of the complete Candida glabrata CST complex. The complex was found to exhibit a 2∶4∶2 or 2∶6∶2 stoichiometry as judged by the ratio of the subunits and the native size of the complex. Stn1, but not Ten1 alone, can directly and stably interact with Cdc13. In gel mobility shift assays, both Cdc13 and CST manifested high-affinity and sequence-specific binding to the cognate telomeric repeats. Single molecule FRET-based analysis indicates that Cdc13 and CST can bind and unfold higher order G-tail structures. The protein and the complex can also interact with non-telomeric DNA in the absence of high-affinity target sites. Comparison of the DNA–protein complexes formed by Cdc13 and CST suggests that the latter can occupy a longer DNA target site and that Stn1 and Ten1 may contact DNA directly in the full CST–DNA assembly. Both Stn1 and Ten1 can be cross-linked to photo-reactive telomeric DNA. Mutating residues on the putative DNA–binding surface of Candida albicans Stn1 OB fold domain caused a reduction in its crosslinking efficiency in vitro and engendered long and heterogeneous telomeres in vivo, indicating that the DNA–binding activity of Stn1 is required for telomere protection. Our data provide insights on the assembly and mechanisms of CST, and our robust reconstitution system will facilitate future biochemical analysis of this important complex

Differential chemotherapeutic regimen cytotoxicity against pancreatic cancer stem cells: a preliminary in vitro study

We are grateful to Scientific Instrumentation Center (CIC) from the Granada University.Introducción: El tratamiento del cáncer de páncreas en estadios avanzados se basa en diferentes regímenes de quimioterapia. Las células madre cancerosas son responsables de la quimiorresistencia tumoral y la recurrencia tras tratamientos en etapa adyuvante y metastásica. El objetivo de este artículo fue evaluar cómo estos regímenes quimioterapéuticos afectan a la proporción de células madre cancerosas y la expresión de sus marcadores. Método: Utilizamos la línea celular de adenocarcinoma pancreático PANC-1 como modelo para aplicar diferentes protocolos quimioterapéuticos (monoterapia y terapia combinada) utilizando 5-Fluorouracilo, Oxaliplatino, Irino tecán, Gemcitabina y Abraxane. Resultados: Tras analizar mediante RT-qPCR diferentes marcadores de células madre tumorales (SOX2, OCT4, CD133, CD44 y CD24) en células de cáncer de páncreas tratadas con diferentes protocolos quimioterapéuticos, el Oxaliplatino y la Gemcitabina en monoterapia fueron los quimioterápicos que seleccionaron en mayor medida las células madre cancerosas mientras que el protocolo FOLFIRI las disminuyó. Conclusiones: En cuanto a la selección de marcadores, ha sido mucho mayor en el caso de Gemcitabina en monoterapia. En conclusión, estos hallazgos podrían mejorar y personalizar la terapia del cáncer de páncreas.Introduction: Pancreatic cancer treatment in advanced stages is based on different chemotherapy regimens. Can cer stem cells are responsible for tumor chemoresistance and recurrence in adjuvant and metastatic settings. The objective of this article was to evaluate how these chemotherapeutic regimens affect the proportion of cancer stem cells and the expression of stemness markers. Method: We used the pancreatic adenocarcinoma cell line PANC-1 as a model to apply different chemotherapeu tic protocols (monotherapy and combined therapy) using 5-Fluorouracil, Oxaliplatin, Irinotecan, Gemcitabine and Abraxane. Results: After analyzing different tumor stem cell markers (SOX2, OCT4, CD133, CD44 and CD24) in pancreatic can cer cells treated with different chemotherapeutic protocols by means of RT-qPCR, Oxaliplatin and Gemcitabine in monotherapy were the chemotherapies that selected the most cancer stem cells while the FOLFIRI protocol de creased them. Conclusions: Regarding the selection of markers, it has been much higher in the case of Gemcitabine alone. In conclusion, these findings could improve and personalize pancreatic cancer therapy.This work was supported by funds from group CTS-107 (Andalusian Government). F. J. Q. acknowledges the FPU2019 grant from the Ministerio de Educacion Ciencia y Deporte y Competitividad (Spain)

Impact of COVID-19 on the degree of compliance with hand hygiene: a repeated cross-sectional study

Hand hygiene (HH) is the paramount measure used to prevent healthcare associated infections. A repeated cross-sectional study was undertaken with direct observation of the degree of compliance on HH of healthcare personnel during the SARS-CoV-2 pandemic. Between, 2018-2019, 9,083 HH opportunities were considered, and 5,821 in 2020-2022. Chi squared tests were used to identify associations. The crude and adjusted odds ratios were used along with a logistic regression model for statistical analyses. Compliance on HH increased significantly (p < 0.001) from 54.5% (95% CI: 53.5, 55.5) to 70.1% (95% CI: 68.9, 71.2) during the COVID-19 pandemic. This increase was observed in four of the five key moments of HH established by the World Health Organization (WHO) (p<0.05), except at moment 4. The factors that were significantly and independently associated with compliance were the time period considered, type of healthcare-personnel, attendance at training sessions, knowledge of HH and WHO guidelines, and availability of hand disinfectant alcoholic solution in pocket format. Highest HH compliance occurred during the COVID-19 pandemic, reflecting a positive change in healthcare-personnel’s behavior regarding HH recommendations.We received funding through the Alicante Institute for Health and Biomedical Research (ISABIAL) plan for scientific and technical research and innovation project number 2021-0392

The Candida albicans Ku70 Modulates Telomere Length and Structure by Regulating Both Telomerase and Recombination

The heterodimeric Ku complex has been shown to participate in DNA repair and telomere regulation in a variety of organisms. Here we report a detailed characterization of the function of Ku70 in the diploid fungal pathogen Candida albicans. Both ku70 heterozygous and homozygous deletion mutants have a wild-type colony and cellular morphology, and are not sensitive to MMS or UV light. Interestingly, we observed complex effects of KU70 gene dosage on telomere lengths, with the KU70/ku70 heterozygotes exhibiting slightly shorter telomeres, and the ku70 null strain exhibiting long and heterogeneous telomeres. Analysis of combination mutants suggests that the telomere elongation in the ku70 null mutant is due mostly to unregulated telomerase action. In addition, elevated levels of extrachromosomal telomeric circles were detected in the null mutant, consistent with activation of aberrant telomeric recombination. Altogether, our observations point to multiple mechanisms of the Ku complex in telomerase regulation and telomere protection in C. albicans, and reveal interesting similarities and differences in the mechanisms of the Ku complex in disparate systems

Cuentos de nunca acabar. Aproximaciones desde la interculturalidad

Cuentos de nunca acabar. Aproximaciones desde la interculturalidad, surge después de la pandemia y su imposibilidad de socializar “en persona” con los compañeros de eventuales encuentros, porque la Comprensión Lectora tenía que reinventarse para su nueva reflexión cognitiva, adaptación contextual y reconstrucción del conocimiento. Este renovado enfoque de la realidad postpandemia, concebido en el marco de la educación intercultural comunitaria, busca potencializar los entornos naturales, sociales y culturales como recursos de aprendizaje multidisciplinario a través del lenguaje animado de los cuentos. En este marco, había que dinamizar la asignatura de Comunicación Oral y Escrita, que se dicta en los Primeros Niveles de los Centros de Apoyo de Otavalo, Cayambe, Latacunga y Riobamba, mediante un eje transversal donde los estudiantes escriban fundamentados en valores de la cosmovisión andina, considerando que provienen de varios lugares de la sierra y amazonía ecuatoriana. Todo surgió del encuentro presencial de un sábado cualquiera donde los estudiantes realizaban ejercicios narrativos, logrando una apreciable respuesta de imaginación, más emotiva que la clásica tarea de las Unidades, tanto así que, pasados unos días, seguían llegando sus escritos a mi correo. Entonces nos pusimos manos a la obra, cada estudiante tendría dos opciones como Actividad Integradora, la primera consistía en escribir un cuento de su propia inspiración, y la segunda analizar un clásico para comentar sus valores y antivalores. La mayor parte de estudiantes decidió escribir su propio cuento, de donde se escogieron algunas participaciones que podrían considerarse originales, para una edición que, respetando la transcripción de la tradición oral que prima en los sectores comunitarios, nos concretamos en revisar la puntuación y ortografía para publicarlos. Con esto buscamos innovar la Actividad Integradora, por algo más práctico y operativo para configurar los Objetos de Aprendizaje que buscamos. Así nació, en medio del camino, este libro de Cuentos de nunca acabar. Aproximaciones desde la interculturalidad, que ponemos en sus manos. Hernán Hermosa Mantilla Quito, junio de 202

Desarrollo y caracterización de salchichas de pollo con microalgas y chia

[ES] En este trabajo se pretende desarrollar salchichas cocidas a base de carne de pollo con microalgas (Arthrospira platensis y Chlorella vulgaris) y Chía (Salvia hispánica L.) La finalidad del trabajo es mejorar el valor nutricional y analizar la incidencia de las microalgas y la chía sobre las características fisicoquímicas y sensoriales de este tipo de producto. Para conseguir el objetivo propuesto se elaboraran varias formulaciones con diferentes % de microalgas y un 1% de chía. Las determinaciones analíticas que se realizaran serán: color, % humedad, aw, CRA, análisis de textura y análisis sensoria[EN] The aim of this work is to develop chicken cooked sausages with microalgae (Arthrospira platensis and Chlorella vulgaris) and Chia (Salvia hispánica L.). The purpose is to improve the nutritional value and to analyze the incidence of microalgae and chia about physicochemical and sensorial characteristics of this type of product. To achieve the proposed objective, several formulations with different% of microalgae and 1% of chia will prepared. The analytical determinations that will be performed are: color,% humidity, aw, CRA, texture analysis and sensory analysis.Chico Sánchez, L. (2017). Desarrollo y caracterización de salchichas de pollo con microalgas y chia. http://hdl.handle.net/10251/89626TFG

Nitrogen ion implantation on stainless steel: AFM study of surface modification

This work presents a study by means of atomic force microscopy (AFM) of the modification of the surface topography of AISI 304 austenitic stainless steel after N-ion implantation, irradiated by 1 × 1015 N 2 +/cm2 at 80 keV. Prior to the implantation surface modification, the samples were electropolished for the optimum observation of the surface at a small scale to obtain an initial surface with the smaller roughness. The electrolytic bath was composed of a mixture of water/sulphuric acid/orthophosphoric acid in percentages 20, 20 and 60%, respectively. Once the surface was optimized, the samples were implanted and observed by AFM, a new technique whose importance relies on its resolution power, allowing the acquisition of topographic images of the surface with nanometric resolution. Thanks to the high resolution power could be observed that ion implantation increases the surface roughness and promotes the apparition of 3 μm wide and 10 nm depth craters as well as the apparition of products with singular morphology. © 2004 Elsevier B.V. All rights reserved.Peer Reviewe

Differential chemotherapeutic regimen cytotoxicity against pancreatic cancer stem cells: a preliminary in vitro study

Introduction: Pancreatic cancer treatment in advanced stages is based on different chemotherapy regimens. Cancer stem cells are responsible for tumor chemoresistance and recurrence in adjuvant and metastatic settings. The objective of this article was to evaluate how these chemotherapeutic regimens affect the proportion of cancer stem cells and the expression of stemness markers.Method: We used the pancreatic adenocarcinoma cell line PANC-1 as a model to apply different chemotherapeutic protocols (monotherapy and combined therapy) using 5-Fluorouracil, Oxaliplatin, Irinotecan, Gemcitabine and Abraxane.Results: After analyzing different tumor stem cell markers (SOX2, OCT4, CD133, CD44 and CD24) in pancreatic cancer cells treated with different chemotherapeutic protocols by means of RT-qPCR, Oxaliplatin and Gemcitabine in monotherapy were the chemotherapies that selected the most cancer stem cells while the FOLFIRI protocol decreased them.Conclusions: Regarding the selection of markers, it has been much higher in the case of Gemcitabine alone. In conclusion, these findings could improve and personalize pancreatic cancer therapy

Citotoxicidad diferencial según el régimen de quimioterapia contra las células madre del cáncer de páncreas: estudio preliminar in vitro

Introduction: Pancreatic cancer treatment in advanced stages is based on different chemotherapy regimens. Cancer stem cells are responsible for tumor chemoresistance and recurrence in adjuvant and metastatic settings. The objective of this article was to evaluate how these chemotherapeutic regimens affect the proportion of cancer stem cells and the expression of stemness markers. Method: We used the pancreatic adenocarcinoma cell line PANC-1 as a model to apply different chemotherapeutic protocols (monotherapy and combined therapy) using 5-Fluorouracil, Oxaliplatin, Irinotecan, Gemcitabine and Abraxane. Results: After analyzing different tumor stem cell markers (SOX2, OCT4, CD133, CD44 and CD24) in pancreatic cancer cells treated with different chemotherapeutic protocols by means of RT-qPCR, Oxaliplatin and Gemcitabine in monotherapy were the chemotherapies that selected the most cancer stem cells while the FOLFIRI protocol decreased them. Conclusions: Regarding the selection of markers, it has been much higher in the case of Gemcitabine alone. In conclusion, these findings could improve and personalize pancreatic cancer therapy.Introducción: El tratamiento del cáncer de páncreas en estadios avanzados se basa en diferentes regímenes de quimioterapia. Las células madre cancerosas son responsables de la quimiorresistencia tumoral y la recurrencia tras tratamientos en etapa adyuvante y metastásica. El objetivo de este artículo fue evaluar cómo estos regímenes quimioterapéuticos afectan a la proporción de células madre cancerosas y la expresión de sus marcadores. Método: Utilizamos la línea celular de adenocarcinoma pancreático PANC-1 como modelo para aplicar diferentes protocolos quimioterapéuticos (monoterapia y terapia combinada) utilizando 5-Fluorouracilo, Oxaliplatino, Irinotecán, Gemcitabina y Abraxane. Resultados: Tras analizar mediante RT-qPCR diferentes marcadores de células madre tumorales (SOX2, OCT4, CD133, CD44 y CD24) en células de cáncer de páncreas tratadas con diferentes protocolos quimioterapéuticos, el Oxaliplatino y la Gemcitabina en monoterapia fueron los quimioterápicos que seleccionaron en mayor medida las células madre cancerosas mientras que el protocolo FOLFIRI las disminuyó. Conclusiones: En cuanto a la selección de marcadores, ha sido mucho mayor en el caso de Gemcitabina en monoterapia. En conclusión, estos hallazgos podrían mejorar y personalizar la terapia del cáncer de páncreas