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  • Ítem
    Description of the antipredatory head-wobble behaviour in Chilean rear-fanged snakes Tachymenis peruviana Wiegmann, 1835 and Tachymenis chilensis coronellina Werner, 1898 (Serpentes, Dipsadidae)
    (Pensoft Publishers, 2022) Reyes-Olivares, Claudio; Vera-Quispe, Alex; Zúñiga, Alejandro; Urra, Félix A.
    In this work, we describe the first records of head-wobble behaviour for Tachymenis peruviana and T. chilensis coronellina. We analyse this behaviour (occurrence, frequency) and accompanying displays in both species. Of particular note is that T. ch. coronellina exhibited more frequent head-wobbling than T. peruviana and, in both records, wind activity was observed during this antipredatory behaviour. Copyright Claudio Reyes-Olivares et al.
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    Domestic dog and alien North American mink as reservoirs of infectious diseases in the endangered Southern river otter
    (Universidad Austral de Chile, 2022) Barros, Macarena; Pons, Daniel J.; Moreno, Andrea; Vianna, Juliana; Ramos, Barbara; Dueñas, Fernando; Coccia, Cristina; Saavedra-Rodríguez, Roberto; Santibañez, Alexis; Medina-Vogel, Gonzalo
    Introduced alien carnivores are host to infectious diseases that may become an important threat for native carnivore species conservation. Canine distemper virus (CDV) is thought to be transmitted among individuals by direct contact and to present viral dynamics associated with a density-dependent multi-host carnivore community. In contrast, Canine Parvovirus (CPV) is mostly transmitted by indirect contact and does not depend only on the density, but also on the social behaviour of infected as well as susceptible hosts. The objective of this study was to assess how introduced American mink (Neovison vison) can act as a bridge-host between domestic dog (Canis familiaris) and Southern river otter (Lontra provocax) in different dog and mink population density scenarios. Our data show that otters are seropositive to both CDV and PV, as well as a molecular identity to Parvovirus in dogs and minks. Furthermore, a strong positive correlation between dog population density and observed seroprevalence of CDV in dogs, minks, and otters was recorded. For Parvovirus, the observed seroprevalence in mink and otters was not correlated to a higher dog population density, but instead a relationship between dog and mink population densities and social behaviour. Our results suggest that introduced American mink and domestic dogs are reservoirs of CDV and PV, both being diseases of major importance for the conservation of native endangered carnivores in Patagonia. © 2022 Universidad Austral de Chile. All rights reserved.
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    Differences in the immune response elicited by two immunization schedules with an inactivated SARS-CoV-2 vaccine in a randomized phase 3 clinical trial
    (eLife Sciences Publications Ltd, 2022) Gálvez, Nicolás M. S.; Pacheco, Gaspar A.; Schultz, Bárbara M.; Melo-González, Felipe; Soto, Jorge A.; Duarte, Luisa F.; González, Liliana A.; Rivera-Pérez, Daniela; Ríos, Mariana; Berrios, Roslye V.; Vázquez, Yaneisi; Moreno-Tapia, Daniela; Vallejos, Omar P.; Andrade, Catalina A.; Hoppe-Elsholz, Guillermo; Iturriaga, Carolina; Urzua, Marcela; Navarrete, María S.; Rojas, Álvaro; Fasce, Rodrigo; Fernández, Jorge; Mora, Judith; Ramírez, Eugenio; Gaete-Argel, Aracelly; Acevedo, Mónica L.; Valiente-Echeverría, Fernando; Soto-Rifo, Ricardo; Weiskopf, Daniela; Grifoni, Alba; Sette, Alessandro; Zeng, Gang; Meng, Weining; González-Aramundiz, José V.; Johnson, Marina; Goldblatt, David; González, Pablo A.; Abarca, Katia; Bueno, Susan M.; Kalergis, Alexis M.
    Background: The development of vaccines to control the coronavirus disease 2019 (COVID-19) pandemic progression is a worldwide priority. CoronaVac is an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine approved for emergency use with robust efficacy and immunogenicity data reported in trials in China, Brazil, Indonesia, Turkey, and Chile. Methods: This study is a randomized, multicenter, and controlled phase 3 trial in healthy Chilean adults aged ≥18 years. Volunteers received two doses of CoronaVac separated by 2 (0–14 schedule) or 4 weeks (0–28 schedule); 2302 volunteers were enrolled, 440 were part of the immunogenicity arm, and blood samples were obtained at different times. Samples from a single center are reported. Humoral immune responses were evaluated by measuring the neutralizing capacities of circulating antibodies. Cellular immune responses were assessed by ELISPOT and flow cytometry. Correlation matrixes were performed to evaluate correlations in the data measured. Results: Both schedules exhibited robust neutralizing capacities with the response induced by the 0–28 schedule being better. No differences were found in the concentration of antibodies against the virus and different variants of concern (VOCs) between schedules. Stimulation of peripheral blood mononuclear cells (PBMCs) with Mega pools of Peptides (MPs) induced the secretion of interferon (IFN)-γ and the expression of activation induced markers in CD4+ T cells for both schedules. Correlation matrixes showed strong correlations between neutralizing antibodies and IFN-γ secretion. Conclusions: Immunization with CoronaVac in Chilean adults promotes robust cellular and humoral immune responses. The 0–28 schedule induced a stronger humoral immune response than the 0–14 schedule. © Gálvez, Pacheco, Schultz et al.
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    Gold nanoparticle based double-labeling of melanoma extracellular vesicles to determine the specificity of uptake by cells and preferential accumulation in small metastatic lung tumors
    (BioMed Central Ltd., 2020) Lara, Pablo; Palma-Florez, Sujey; Salas-Huenuleo, Edison; Polakovicova, Iva; Guerrero, Simón; Lobos-Gonzalez, Lorena; Campos, America; Muñoz, Luis; Jorquera-Cordero, Carla; Varas-Godoy, Manuel; Cancino, Jorge; Arias, Eloísa; Villegas, Jaime; Cruz, Luis J.; Albericio, Fernando; Araya, Eyleen; Corvalan, Alejandro H.; Quest, Andrew F. G.; Kogan, Marcelo J.
    Background: Extracellular vesicles (EVs) have shown great potential for targeted therapy, as they have a natural ability to pass through biological barriers and, depending on their origin, can preferentially accumulate at defined sites, including tumors. Analyzing the potential of EVs to target specific cells remains challenging, considering the unspecific binding of lipophilic tracers to other proteins, the limitations of fluorescence for deep tissue imaging and the effect of external labeling strategies on their natural tropism. In this work, we determined the cell-type specific tropism of B16F10-EVs towards cancer cell and metastatic tumors by using fluorescence analysis and quantitative gold labeling measurements. Surface functionalization of plasmonic gold nanoparticles was used to promote indirect labeling of EVs without affecting size distribution, polydispersity, surface charge, protein markers, cell uptake or in vivo biodistribution. Double-labeled EVs with gold and fluorescent dyes were injected into animals developing metastatic lung nodules and analyzed by fluorescence/computer tomography imaging, quantitative neutron activation analysis and gold-enhanced optical microscopy. Results: We determined that B16F10 cells preferentially take up their own EVs, when compared with colon adenocarcinoma, macrophage and kidney cell-derived EVs. In addition, we were able to detect the preferential accumulation of B16F10 EVs in small metastatic tumors located in lungs when compared with the rest of the organs, as well as their precise distribution between tumor vessels, alveolus and tumor nodules by histological analysis. Finally, we observed that tumor EVs can be used as effective vectors to increase gold nanoparticle delivery towards metastatic nodules. Conclusions: Our findings provide a valuable tool to study the distribution and interaction of EVs in mice and a novel strategy to improve the targeting of gold nanoparticles to cancer cells and metastatic nodules by using the natural properties of malignant EVs. © 2020 The Author(s).
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    Eco-efficiency assessment of domestic wastewater treatment technologies used in Chile
    (Instituto Mexicano de Tecnologia del Agua, 2020) Abello-Passteni, Valentina; Alvear, Edmundo Muñoz; Lira, Sebastián; Garrido-Ramírez, Elizabeth
    Wastewater treatment plants have been the widest technologies used to mitigate the environmental impacts of domestic wastewater. Currently, Chile has the largest coverage of wastewater sanitation (99.85%) of Latin American, through the use of conventional technologies, mainly active sludge and aerated lagoons and also unconventional technologies such as biofilter, vermi-biofilter, among others. Although all technologies allow fulfilling with discharge standards, there are differences in the flows of matter and energy associated with the kind of technology used, which implies the generation of different environmental impacts. The objective of this research was to evaluate the eco-efficiency of different domestic wastewater treatment technologies used in Chile, based on the requirements of ISO 14045 (2012). For this purpose, 1 kg of removed BOD5 was used as a functional unit and a value function associated with the volume of treated water (m3). Fifteen plants of wastewater treatment in Chile were analyzed, using the life cycle assessment methodology to quantify environmental impacts. The main environmental aspect of domestic wastewater treatment for most of the impact categories studied was electricity consumption. The vermi-biofilter was the most eco-efficient technology for climate change and freshwater eutrophication categories. This result reflecting that unconventional emerging technologies are more eco-efficient than conventional ones. © 2020 Instituto Mexicano de Tecnologia del Agua. All rights reserved.
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    Characterization of microbial communities and predicted metabolic pathways in the uterus of healthy mares
    (Faculty of Veterinary Medicine, University of Tripoli, 2022) Thomson, Pamela; Pareja, Josefina; Núñez, Andrea; Santibáñez, Rodrigo; Castro, Rodrigo
    Background: Culture-independent techniques have made it possible to expand the knowledge about the composition of bacterial communities present in the healthy uterus and their role in health and disease, mainly in humans. However, in animals like mares, there is a dearth of information regarding this area. Aim: To narrow this knowledge gap, the objective of this study was to identify and characterize the composition and function of the uterine microbiome of a group of Chilean purebred mares (CPM), an equine breed with the oldest genealogical record in South America and an economical important reproductive industry. Methods: From uterine biopsy samples obtained during estrus, DNA extraction and targeted sequencing were performed to investigate the bacterial diversity and its probable metabolic function. Results: CPM biopsy samples were characterized by having a varied microbial composition, where the four most relatively abundant phyla were Proteobacteria (69.6%), Firmicutes (21.1%), Bacteroidetes (7.8%), and Actinobacteria (1.06%); which made up 99.6% of the total identified phyla. In contrast, Actinobacteria and Fusobacteria were the phyla not identified in all samples. Of a total of 59 genera identified across all samples, Staphylococcus was the most abundant genus with an average relative abundance of 18.88%, followed by Pseudomonas (17.9%), Escherichia/ Shigella (10.42%), and Klebsiella (9.92%). Conclusion: These findings contribute to the knowledge of microbes' presence in the uterus, while future studies are required to demonstrate the role of these microorganisms in health and disease. © 2022, Faculty of Veterinary Medicine, University of Tripoli. All rights reserved.
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    Back to the settlement: Resistance and melancholy on the borders of the formal city
    (Universidad de Chile, Instituto de la Vivienda, 2017) Martínez, Rodrigo Esteban Morales; Arrau, Carolina Beatriz Besoain; Morales, Alejandro Soto; de Carvalho, Laís Pinto; Pino, Karla Dominique Hidalgo; Posada, Ismael Fernández; Santibáñez, Vicente Bernal
    This paper presents the main findings of research whose objective was to explore the experience of some residents within the Chilean housing policy context. Based on previous studies, this research analyzes the processes of subjectivisation experienced by a group of residents who, despite being provided with social housing from 1980 to 2000, decided to return to their former settlements. Qualitative social research and ethnographic methods were used to compile data for two settlements located in the municipalities of Lampa and San Bernardo, Santiago, for the period 2014 to 2015. This data was analyzed from a perspective of discourse analysis. It is suggested that the repopulation of settlements is a counter-movement to subjectivation processes generated by the provision of social housing, the result being the disruption of the housing process, the idealization of the past and the yearning for different recognition and inhabiting experiences. This paper analyzes the concept of return in the two senses of resistance and failure determined by the search for an impossible place that reflects the different wishes, frustrations and conflicts common to the experience of inhabiting the borders of the formal city. © 2017 Universidad de Chile, Instituto de la Vivienda. All rights reserved.
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    UUAT1 is a golgi-localized UDP-uronic acid transporter that modulates the polysaccharide composition of arabidopsis seed mucilage
    (American Society of Plant Biologists, 2017) Saez-Aguayo, Susana; Rautengarten, Carsten; Temple, Henry; Sanhueza, Dayan; Ejsmentewicz, Troy; Sandoval-Ibañez, Omar; Doñas, Daniela; Parra-Rojas, Juan Pablo; Ebert, Berit; Lehner, Arnaud; Mollet, Jean-Claude; Dupree, Paul; Scheller, Henrik V.; Heazlewood, Joshua L.; Reyes, Francisca C.; Orellana, Ariel
    UDP-glucuronic acid (UDP-GlcA) is the precursor of many plant cell wall polysaccharides and is required for production of seed mucilage. Following synthesis in the cytosol, it is transported into the lumen of the Golgi apparatus, where it is converted to UDP-galacturonic acid (UDP-GalA), UDP-arabinose, and UDP-xylose. To identify the Golgi-localized UDP-GlcA transporter, we screened Arabidopsis thaliana mutants in genes coding for putative nucleotide sugar transporters for altered seed mucilage, a structure rich in the GalA-containing polysaccharide rhamnogalacturonan I. As a result, we identified UUAT1, which encodes a Golgi-localized protein that transports UDP-GlcA and UDP-GalA in vitro. The seed coat of uuat1 mutants had less GalA, rhamnose, and xylose in the soluble mucilage, and the distal cell walls had decreased arabinan content. Cell walls of other organs and cells had lower arabinose levels in roots and pollen tubes, but no differences were observed in GalA or xylose contents. Furthermore, the GlcA content of glucuronoxylan in the stem was not affected in the mutant. Interestingly, the degree of homogalacturonan methylation increased in uuat1. These results suggest that this UDP-GlcA transporter plays a key role defining the seed mucilage sugar composition and that its absence produces pleiotropic effects in this component of the plant extracellular matrix. © 2016 American Society of Plant Biologists.
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    Heterologous expression, purification and characterization of three novel esterases secreted by the lignocellulolytic fungus Penicillium purpurogenum when grown on sugar beet pulp
    (Elsevier Ltd, 2017) Oleas, Gabriela; Callegari, Eduardo; Sepúlveda, Romina; Eyzaguirre, Jaime
    The lignocellulolytic fungus, Penicillium purpurogenum, grows on a variety of natural carbon sources, among them sugar beet pulp. Culture supernatants of P. purpurogenum grown on sugar beet pulp were partially purified and the fractions obtained analyzed for esterase activity by zymograms. The bands with activity on methyl umbelliferyl acetate were subjected to mass spectrometry to identify peptides. The peptides obtained were probed against the proteins deduced from the genome sequence of P. purpurogenum. Eight putative esterases thus identified were chosen for future work. Their cDNAs were expressed in Pichia pastoris. The supernatants of the recombinant clones were assayed for esterase activity, and five of the proteins were active against one or more substrates: methyl umbelliferyl acetate, indoxyl acetate, methyl esterified pectin and fluorescein diacetate. Three of those enzymes were purified, further characterized and subjected to a BLAST search. Based on their amino acid sequence and properties, they were identified as follows: RAE1, pectin acetyl esterase (CAZy family CE 12); FAEA, feruloyl esterase (could not be assigned to a CAZy family) and EAN, acetyl esterase (former CAZy family CE 10). © 2017 Elsevier Ltd
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    Characterization of Clostridioides difficile Persister Cells and Their Role in Antibiotic Tolerance
    (Multidisciplinary Digital Publishing Institute (MDPI), 2024-07) Inostroza, Osvaldo; Fuentes, Juan A.; Yáñez, Paulina; Espinoza, Giovanni; Fica, Omar; Queraltó, Camila; Rodríguez, José; Flores, Isidora; González, Ruth; Soto, Jorge A.; Calderón, Iván L.; Gil, Fernando
    Clostridioides difficile is a Gram-positive pathogen known for its toxin production and spore formation. It is primarily responsible for most cases of antibiotic-associated diarrhea. Bacterial persisters are a small subset of the population that exhibits transient tolerance to bactericidal substances, and they are of significant medical concern due to their association with the emergence of antibiotic resistance and difficult-to-treat chronic or recurrent infections. Vancomycin, the predominant antibiotic utilized in the management of C. difficile infection, is extensively applied in the realm of clinical practice. Previous studies have demonstrated a persister-like phenotype with treatments involving this antibiotic. However, the mechanism in C. difficile remains largely unknown, primarily due to the challenge of isolating this small population at any given time. To better characterize C. difficile persister cells, we present a study that enables the enrichment and characterization of persister cells from bacterial cultures in both the exponential and stationary phases. Moreover, we could differentiate between triggered (induced using antibiotics such as vancomycin) and spontaneous (stochastic) persister cells. Additionally, we observed the involvement of toxin-antitoxin systems and Clp proteases in persister cell formation.
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    Draft Genome Sequence of Tenacibaculum haliotis Strain RA3-2T, Isolated from Korean Wild Abalone (Haliotis discus hannai)
    (American Society for Microbiology, 2023-03) Avendaño-Herrera, Ruben; Saldarriaga-Córdoba, Mónica; Araya-León, Henry; Irgang, Rute
    Here, we present the draft genome sequence of Tenacibaculum haliotis strain RA3-2T (i.e., KCTC 52419T and NBRC 112382T), isolated from Korean wild abalone (Haliotis discus hannai). As the only strain for this Tenacibaculum species worldwide, the information is of use for comparative genomic analyses delineating Tenacibaculum species. Copyright © 2023 Avendaño-Herrera et al.
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    Increased Absorption of Thyroxine in a Murine Model of Hypothyroidism Using Water/CO2 Nanobubbles
    (Multidisciplinary Digital Publishing Institute (MDPI), 2024-06) Opazo, Maria Cecilia; Yañez, Osvaldo; Márquez-Miranda, Valeria; Santos, Johana; Rojas, Maximiliano; Araya-Durán, Ingrid; Aguayo, Daniel; Leal, Matías; Duarte, Yorley; Kohanoff, Jorge; González-Nilo, Fernando D.
    Thyroxine (T4) is a drug extensively utilized for the treatment of hypothyroidism. However, the oral absorption of T4 presents certain limitations. This research investigates the efficacy of CO2 nanobubbles in water as a potential oral carrier for T4 administration to C57BL/6 hypothyroid mice. Following 18 h of fasting, the formulation was administered to the mice, demonstrating that the combination of CO2 nanobubbles and T4 enhanced the drug’s absorption in blood serum by approximately 40%. To comprehend this observation at a molecular level, we explored the interaction mechanism through which T4 engages with the CO2 nanobubbles, employing molecular simulations, semi-empirical quantum mechanics, and PMF calculations. Our simulations revealed a high affinity of T4 for the water–gas interface, driven by additive interactions between the hydrophobic region of T4 and the gas phase and electrostatic interactions of the polar groups of T4 with water at the water–gas interface. Concurrently, we observed that at the water–gas interface, the cluster of T4 formed in the water region disassembles, contributing to the drug’s bioavailability. Furthermore, we examined how the gas within the nanobubbles aids in facilitating the drug’s translocation through cell membranes. This research contributes to a deeper understanding of the role of CO2 nanobubbles in drug absorption and subsequent release into the bloodstream. The findings suggest that utilizing CO2 nanobubbles could enhance T4 bioavailability and cell permeability, leading to more efficient transport into cells. Additional research opens the possibility of employing lower concentrations of this class of drugs, thereby potentially reducing the associated side effects due to poor absorption.
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    Ultramafic rocks in the north patagonian andes: Is their emplacement associated with the neogene tectonics of the liquiñe-ofqui fault zone?
    (Servicio Nacional de Geologia y Mineria, 2017-01) Hervé, Francisco; Fuentes, Francisco; Calderón, Mauricio; Fanning, Mark; Quezada, Paulo; Pankhurst, Robert; Rapela, Carlos
    Serpentinites and fresh or partially serpentinized harzburgite crop out in the western slope of the North Patagonian Andes of continental Chiloé (41°44’-42°12’S). These rocks are spatially associated with low-grade metamorphic rocks containing Cenozoic detrital zircons. The metamorphic rocks, together with Devonian metasediments, have been mapped previously as Late Paleozoic-Triassic metamorfic complex, an age no longer tenable for at least part of the complex. Transpressional tectonic emplacement of the ultramafic body or bodies is thought to have been related to activity on the Liquiñe-Ofqui Fault Zone, following a late Oligocene-Early Miocene extensional phase in the forearc region of the present Andes. This fault zone occurs immediately east of the outcrops of the ultramafic rocks and has been interpreted previously as generating a hemi-flower or flower structure. © 2017, Servicio Nacional de Geologia y Mineria. All Rights Reserved.
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    Editorial: Ecological and evolutionary relevance of phenotypic plasticity in a changing world
    (Frontiers Media S.A., 2023-02) Ivimey-Cook, Edward R.; Cortes, Pablo A.; Carter, Mauricio J.
    Understanding the ecological and evolutionary consequences of phenotypic plasticity, the ability of an individual genotype to produce different phenotypes in response to environmental variability, is crucial to consider in light of the rapid change in global environmental conditions that we are now experiencing (Kingsolver and Buckley, 2017). Whilst the evolutionary potential to respond to these novel environments is still debatable, increasing our knowledge of such a process gives us indispensable information into the mechanisms that will underpin the changes to an organism's distributional range and local extinction probability (Merilä and Hendry, 2014). This Research Topic aimed to bring together a wealth of different eco-physiological disciplines, from evolution to physiology, to better understand the mechanisms that allow organisms both at the individual and at the population level, to maximize fitness and survival in response to changing environments.
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    O-Alkyl derivatives of ferulic and syringic acid as lipophilic antioxidants: effect of the length of the alkyl chain on the improvement of the thermo-oxidative stability of sunflower oil
    (Royal Society of Chemistry, 2024-07-16) Forero-Doria, Oscar; Guzmán, Luis; Venturini, Whitney; Zapata-Gomez, Felipe; Duarte, Yorley; Camargo-Ayala, Lorena; Echeverría, Cesar; Echeverría, Javier
    Lipid oxidation is the major cause of the deterioration of fat-containing foods, especially those containing polyunsaturated fatty acids (PUFAs). Antioxidant additives of synthetic origin are added to matrices rich in PUFAs, such as sunflower oil (SO). However, there is controversy regarding their safety, and their low solubility in both water and fat has led to the search for new covalent modifications through lipophilicity. This work presents the synthesis of O-alkyl acid derivatives from ferulic and syringic acids and the study of their antioxidant capacity and effect on the thermoxidative degradation of SO. Antioxidant activities were evaluated by employing ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays in a concentration range of 10-100 µg mL−1. The IC50 values for DPPH scavenging activity ranged from 15.61-90.43 µg mL−1. The results of the FRAP assay for both O-alkyl ferulic (3a-f) and syringic (5a-f) series revealed a “cut-off” effect on antioxidant activity in carbon five (C5). Thermoxidation study of additives 3b-c and 5b-c showed a decrease in the slope of extinction coefficients K232 and K270 in comparison with SOcontrol. Furthermore, 3c presented higher antioxidant activity than 3b and 1, with a power to decrease the thiobarbituric acid reactive species (TBARS) 6 times higher than SOcontrol at 220 °C. Additives 5b-c exerted a protective effect on the thermoxidation of SO. The results suggest that increasing lipophilic and thermal properties of antioxidants through O-alkyl acid derivatization is an effective strategy for accessing lipophilic antioxidant additives with potential use in food matrices.
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    Mitochondrial ASncmtRNA-1 and ASncmtRNA-2 as potent targets to inhibit tumor growth and metastasis in the RenCa murine renal adenocarcinoma model
    (Impact Journals LLC, 2017) Borgna, Vincenzo; Villegas, Jaime; Burzio, Verónica A.; Belmar, Sebastián; Araya, Mariela; Jeldes, Emanuel; Lobos-González, Lorena; Silva, Verónica; Villota, Claudio; Oliveira-Cruz, Luciana; Lopez, Constanza; Socias, Teresa; Castillo, Octavio; Burzio, Luis O.
    Knockdown of antisense noncoding mitochondrial RNAs (ASncmtRNAs) induces apoptosis in several human and mouse tumor cell lines, but not normal cells, suggesting this approach for a selective therapy against different types of cancer. Here we show that in vitro knockdown of murine ASncmtRNAs induces apoptotic death of mouse renal adenocarcinoma RenCa cells, but not normal murine kidney epithelial cells. In a syngeneic subcutaneous RenCa model, treatment delayed and even reversed tumor growth. Since the subcutaneous model does not reflect the natural microenviroment of renal cancer, we used an orthotopic model of RenCa cells inoculated under the renal capsule. These studies showed inhibition of tumor growth and metastasis. Direct metastasis assessment by tail vein injection of RenCa cells also showed a drastic reduction in lung metastatic nodules. In vivo treatment reduces survivin, N-cadherin and P-cadherin levels, providing a molecular basis for metastasis inhibition. In consequence, the treatment significantly enhanced mouse survival in these models. Our results suggest that the ASncmtRNAs could be potent and selective targets for therapy against human renal cell carcinoma. © Borgna et al.
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    Sporotrichosis Outbreak Due to Sporothrix brasiliensis in Domestic Cats in Magallanes, Chile: A One-Health-Approach Study
    (MDPI, 2023-02) Thomson, Pamela; González, Carlos; Blank, Olivia; Ramírez, Valentina; Río, Camila del; Santibáñez, Sebastián; Pena, Pamela
    Sporotrichosis is an implantation mycosis with subcutaneo-lymphatic or, more rarely, a viscerally disseminated affection; it can be acquired through traumatic percutaneous inoculation of the fungus present in soil or plant matter, or by feline scratching. Among the causative agents, Sporothrix brasiliensis is considered the most virulent species with a high prevalence in Brazil and recently in Argentina. Objective: To describe a S. brasiliensis outbreak in domestic and feral cats detected in the Magallanes region of southern Chile. Materials and Methods: Between the months of July and September 2022, three cats presented with suppurative subcutaneous lesions located mainly on the head and thoracic limbs. The cytology revealed the presence of yeasts with morphological characteristics suggestive of Sporothrix spp. The histopathology confirmed pyogranulomatous subcutaneous lesions associated with the presence of the same yeasts. The fungal culture followed by the partial gene sequence and analysis of the ITS region confirmed the diagnosis of the S. brasiliensis as the causative agent. The cats were treated with itraconazole associated in one case with potassium iodide. The evolution of the patients was favorable in all cases. Conclusions: An outbreak caused by S. brasiliensis was detected in domestic and feral cats in austral Chile. The correct identification of this fungus and antifungigram is essential for treatment decisions and for designing dissemination control and prevention programs under a one health approach that consider the health of people, animals, and the environment. © 2023 by the authors.
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    Complexity and Evolution
    (MDPI, 2023-02) Veloz, Tomas; Heylighen, Francis; Witkowski, Olaf
    Understanding the underlying structure of evolutionary processes is one the most important issues of scientific enquiry of this century. In the twentieth century, scientific thinking witnessed the overwhelming power of the evolutionary paradigm. It not only solidified the foundations of diverse areas, such as cell-biology, ecology, and economics, but also fostered the development of novel mathematical and computational tools to model and simulate how evolutionary processes take place. In addition to the application of the evolutionary paradigm and the discovery of the evolutionary features for processes of diverse nature, there is another interesting aspect which touches upon the emergence of novel evolutionary processes. Namely, the emergence of an evolutionary process requires a complex transition between a prior form where no evolutionary process is undergoing and a posterior form where the evolutionary process has been triggered. Theoretical methods to describe the emergence of evolutionary processes require the consideration of complex systemic notions, such as self-organization, resilience, contex tuality, among others. Therefore, complexity and evolution became intertwined notions: evolution not only leads to but also depends on the development of increasingly complex forms and functions.
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    Apoptotic Induction in Human Cancer Cell Lines by Antimicrobial Compounds from Antarctic Streptomyces fildesensis (INACH3013)
    (MDPI, 2023-02) Astudillo-Barraza, David; Oses, Romulo; Henríquez-Castillo, Carlos; Vui Ling Wong, Clemente Michael; Pérez-Donoso, José M.; Purcarea, Cristina; Fukumasu, Heidge; Fierro-Vásquez, Natalia; Pérez, Pablo A.; Lavin, Paris
    The Antarctic Streptomyces fildesensis has been recognized for its production of antimicrobial compounds with interesting biological activities against foodborne bacteria and multi-resistant strains, but not for its potential antiproliferative activity and mechanisms involved. Two bioactive ethyl acetate extract (EAE) fractions were purified via thin-layer chromatography and High-Performance Liquid Chromatography (HPLC), showing that orange-colored compounds displayed antimicrobial activity against pathogenic bacteria even after shock thermal treatment. The UV–VIS features of the active compounds, the TLC assay with actinomycin-D pure standard, Fourier transform infrared (FTIR) spectra and the ANTISMASH analysis support the presence of actinomycin-like compounds. We demonstrated that S. fildesensis displays antiproliferative activity against human tumor cell lines, including human breast cancer (MCF-7), prostate cancer (PC-3), colon cancer (HT-29) and non-tumoral colon epithelial cells (CoN). The half-maximal effective concentrations (EC50) ranged from 3.98 µg/mL to 0.1 µg/mL. Our results reveal that actinomycin-like compounds of S. fildesensis induced apoptosis mediated by caspase activation, decreasing the mitochondrial membrane potential and altering the cell morphology in all tumoral and non-tumoral cell lines analyzed. These findings confirm the potential of the psychrotolerant Antarctic S. fildesensis species as a promising source for obtaining potential novel anticancer compounds. © 2023 by the authors.
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    Antimicrobial Consumption in the Livestock Sector in Bhutan: Volumes, Values, Rates, and Trends for the Period 2017–2021
    (MDPI, 2023-02) Gurung, Ratna B.; Zangmo, Karma P.; Gilkerson, James R.; Browning, Glenn F.; Ferdinand, Angeline S.; Coppo, Mauricio J. C.
    Data on the use of antimicrobials in humans and livestock may provide evidence to guide policy changes to mitigate the risk of antimicrobial resistance (AMR). However, there is limited information available about antimicrobial use in livestock in low- and middle-income countries, even though these nations are most vulnerable to the impact of AMR. This study aimed to assess the consumption of veterinary antimicrobials in Bhutan and identify areas for improvement to reduce the use of antimicrobials in livestock. National data on livestock numbers and annual procurement of veterinary antimicrobials over five years (2017–2021) were used to calculate rates of antimicrobial consumption and annual national expenditure on veterinary antimicrobials in Bhutan. The rate of antimicrobial consumption in Bhutan was 3.83 mg per population correction unit, which is lower than most countries in Europe, comparable with the rates of consumption in Iceland and Norway, and approximately 120-fold lower than published rates of antimicrobial consumption in South Asian countries, including Nepal and Pakistan. The low rates of antimicrobial consumption by the animal health sector in Bhutan could be attributable to stronger governance of antimicrobial use in Bhutan, higher levels of compliance with regulation, and better adherence to standard guidelines for antimicrobial treatment of livestock. © 2023 by the authors.