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A Regenerative Endodontic Approach in Mature Ferret Teeth Using Rodent Preameloblast-conditioned Medium
(2019) CRISTINA BUCCHI; ÁLVARO GIMENO SANDIG; IVÁN VALDIVIA-GANDUR; CRISTINA MANZANARES CÉSPEDES; JOSEP MARIA DE ANTA
Regenerative endodontics, revitalization, mature teeth, ferrets, pulp regeneration
Absence of Cyanotoxins in Llayta, Edible Nostocaceae Colonies from the Andes Highlands
(2020) Alexandra Galetović ; Joana Azevedo; Raquel Castelo-Branco; Falvio Oliveira; Bneito Gómez-Silva; Vitor Vasconselos
Edible Llayta are cyanobacterial colonies consumed in the Andes highlands. Llayta and four isolated cyanobacteria strains were tested for cyanotoxins (microcystin, nodularin, cylindrospermopsin, saxitoxin and -N-methylamino-L-alanine—BMAA) usingmolecular and chemicalmethods. All isolates were free of target genes involved in toxin biosynthesis. Only DNA from Llayta amplified the mcyE gene. Presence of microcystin-LR and BMAA in Llayta extracts was discarded by LC/MS analyses. The analysed Llayta colonies have an incomplete microcystin biosynthetic pathway and are a safe food ingredient.
Aqueous Dried Extract of Skytanthus acutus Meyen as Corrosion Inhibitor of Carbon Steel in Neutral Chloride Solutions
(2021) Luis Cáceres; Yohana Frez; Felipe Galleguillos; Alvaro Soliz; Benito Gómez-Silva; Jorge Borquez
The implementation of corrosion engineering control methods and techniques is crucial to extend the life of urban and industrial infrastructure assets and industrial equipment affected by natural corrosion. Then, the search of stable and environmentally friendly corrosion inhibitors is an important pending task. Here, we provide experimental evidence on the corrosion inhibitory activity of aqueous extracts of Skytanthus acutus Meyen leaf, a native plant from the Atacama Desert in northern Chile. Skytanthus extracts as a powder should be prepared at 55 °C to avoid thermal decomposition and loss of corrosion inhibitory activity. Corrosion of carbon steel AISI1020 immersed in 0.5 M NaCl was evaluated in the presence of different doses of Skytanthus extract by complementary and simultaneous linear polarization, electrochemical impedance spectroscopy, and weight-loss technique under high hydrodynamic conditions. Mixed Potential Theory was applied to confirm the electrochemical activity of the extract inhibitory capabilities. The Skytanthus extracts reached a 90% corrosion inhibitory efficiency when tested at 100 to 1200 ppm in a time span of 48 h, through an electrochemical interaction between the extract inhibitor component and the carbon steel surface. The corrosion inhibition activity observed in Skytanthus dry extracts involves a protective film formation by a mechanism that includes an iron dissolution at the expense of either oxygen reduction and/or hydrogen evolution, followed by a ferrous-ferric iron cycling, the formation of an iron complex and adsorption to the metal surface, and, finally, desorption or degradation of the protecting film. The water-soluble plant extract was subjected to HPLC-MS analyses that rendered 14 major signals, with quinic acid, protocatechuic acid, chlorogenic acid isomers, vanillic acid hexoside, and patuletin 3-methoxy-7-glucoside as the most abundant components. Then, we propose that a phenolic derivative is responsible for the corrosion inhibitory activity found in Skytanthus extracts.
Baroreflex and chemoreflex interaction in high-altitude exposure: possible role on exercise performance
(2024) Pablo Alvarez Araos; Sergio Jiménez; Camila Salazar Ardiles; Cristian Núñez Espinosa; Valeria Paez; Maria Rodriguez Fernandez; Antoine Raberin; Gregoire P. Millet; Rodrigo Iturriaga; David C. Andrade
The hypoxic chemoreflex and the arterial baroreflex are implicated in the ventilatory response to exercise. It is well known that long-term exercise training increases parasympathetic and decreases sympathetic tone, both processes influenced by the arterial baroreflex and hypoxic chemoreflex function. Hypobaric hypoxia (i.e., high altitude [HA]) markedly reduces exercise capacity associated with autonomic reflexes. Indeed, a reduced exercise capacity has been found, paralleled by a baroreflex-related parasympathetic withdrawal and a pronounced chemoreflex potentiation. Additionally, it is well known that the baroreflex and chemoreflex interact, and during activation by hypoxia, the chemoreflex is predominant over the baroreflex. Thus, the baroreflex function impairment may likely facilitate the exercise deterioration through the reduction of parasympathetic tone following acute HA exposure, secondary to the chemoreflex activation. Therefore, the main goal of this review is to describe the main physiological mechanisms controlling baro- and chemoreflex function and their role in exercise capacity during HA exposure.
Baroreflex Modulation During Acute High-Altitude Exposure in Rats
(2020) Ana Rosa Beltrán; Alexis Arce-Álvarez; Rodrigo Ramirez-Campillo; Manuel Vásquez-Muñoz; Magdalena von Igel; Marco Antonio Ramírez; Rodrigo Del Rio; David C. Andrade
Baroreflex (BR) control is critically dependent of sympathetic and parasympathetic modulation. It has been documented that during acute hypobaric hypoxia there is a BR control impairment, however, the effect of a natural hypoxic environment on BR function is limited and controversial. Therefore, the aim of this study was to determine the effect of acute High-Altitude exposure on sympathetic/parasympathetic modulation of BR control in normal rats. Male Sprague Dawley rats were randomly allocated into Sea-Level (n = 7) and High-Altitude (n = 5) (3,270 m above sea level) groups. The BR control was studied using phenylephrine (Phe) and sodium nitroprusside (SNP) through sigmoidal analysis. The autonomic control of the heart was estimated using heart rate variability (HRV) analysis in frequency domain. Additionally, to determine the maximum sympathetic and parasympathetic activation of BR, spectral non-stationary method analysis, during Phe (0.05 mg/mL) and SNP administration (0.10 mg/mL) were used. Compared to Sea-Level condition, the High-Altitude group displayed parasympathetic withdrawal (high frequency, 0.6–2.4 Hz) and sympathoexcitation (low frequency, 0.04–0.6 Hz). Regarding to BR modulation, rats showed a significant decrease (p < 0.05) of curvature and parasympathetic bradycardic responses to Phe, without significant differences in sympathetic tachycardic responses to SNP after High-Altitude exposure. In addition, the non-stationary analysis of HRV showed a reduction of parasympathetic activation (Phe) in the High-Altitude group. Our results suggest that acute exposure to High-Altitude produces an autonomic and BR control impairment, characterized by parasympathetic withdrawal after 24 h of high-altitude exposure.
Blood Pressure Response in Miners Exposed to Chronic Intermittent Hypoxia in Chile
(2021) Moring Lang; Valeria Paéz; Giacomo Maj; Juan Silva-Urra; Cristián Labarca-Valenzuela; Sergio Caravita; Andrea Faini; Javier Cantuarias; Oscar Perez; Grzegorz Bilo; Gianfranco Parati
Introduction: Limited information is available on blood pressure (BP) behavior in workers exposed to chronic intermittent hypoxia (CIH), and even less is known regarding effects of CIH on 24-h ambulatory BP in those affected by arterial hypertension at sea level (SL). The aims of this study were to assess clinic and 24-h ambulatory BP at SL and at high altitude (HA; 3,870 m above SL) in workers exposed to CIH, and to compare BP response to HA exposure between normotensive and hypertensive workers. Methods: Nineteen normotensive and 18 pharmacologically treated hypertensive miners acclimatized to CIH were included, whose work was organized according to a "7 days-on-7 days-off" shift pattern between SL and HA. All measurements were performed on the second and seventh day of their HA shift and after the second day of SL sojourn. Results: Compared to SL, 24-h systolic BP (SBP) and diastolic BP (DBP) increased at HA [+14.7 ± 12.6 mmHg (p < 0.001) and +8.7 ± 7.2 mmHg (p < 0.001), respectively], and SBP nocturnal fall decreased consistently (-4.1 ± 9.8%; p < 0.05) in all participants, with hypertensives showing higher nocturnal DBP than normotensives (p < 0.05) despite the current therapy. Also, heart rate (HR) nocturnal fall tended to be reduced at HA. In addition, the 24-h SBP/DBP hypertension threshold of ≥130/80 mmHg was exceeded by 39% of workers at SL and by 89% at HA. Clinic HR, SBP, and DBP were significantly higher on the second day of work at HA compared with SL, the increase being more pronounced for SBP in hypertensives (p < 0.05) and accompanied by, on average, mild altitude sickness in both groups. These symptoms and the values of all cardiovascular variables decreased on the seventh day at HA (p < 0.05) regardless of CIH exposure duration. Conclusion: Long history of work at HA according to scheduled CIH did not prevent the occurrence of acute cardiovascular changes at HA during the first days of exposure. The BP response to HA tended to be more pronounced in hypertensive than in normotensive workers despite being already treated; the BP changes were more evident for 24-h ambulatory BP. Twenty-four-hour ABP monitoring is a useful tool for an appropriate evaluation of BP in CIH workers
Cardiac Autonomic Modulation in Response to Muscle Fatigue and Sex Differences During Consecutive Competition Periods in Young Swimmers: A Longitudinal Study
(2021) Matías Castillo Aguilar; Pablo Valdés Badilla; Tomás Herrera Valenzuela; Eduardo Guzmán Muñoz; Pedro Delgado Floody; David Cristóbal Andrade; Michele M. Moraes; Rosa M. E. Arantes; Cristian Núñez Espinosa
Objective: To study the differences in cardiac autonomic modulation in response to muscle fatigue caused by high-intensity exercise during two consecutive competition periods in young swimmers. Methods: Twenty-six competitive swimmers, selected by their training volume, were separated in two groups, females (n = 12 [46%], age: 13.5 1.4 years) and males (n = 14 [54%], age: 13.9 1.7 years), aged between 10 and 16 years, were evaluated five times as follow: (i) 21 days before the first competition (t-0); (ii) two days before (t-1; t-3); and (iii) two days after (t-2; t-4) of the first and second competitions. Morphological measurements (body mass, percentage of total body fat and height), blood pressure, power, and resting heart rate variability (RR with Polar band) were recorded before and after Wingate test at each time. Results: Body fat was higher in females compared to males. However, no differences were found in other morphological parameters. An intra-subject analysis grouped by sex in cardiovascular parameters shows longitudinal variations in systolic pressure and mean pressure among females. Additionally, females depicted higher, very low frequency (VLF, which is intrinsically generated by the heart and strongly associated with emotional stress) after physical fatigue compared to males at t-1. Further, before the competition, the high frequency (HF) component of HRV (parasympathetic drive) was higher in males than females at t-0 and t-4. Conclusion: Our data revealed that males displayed greater parasympathetic reactivity after an anaerobic muscle fatigue test during their competition periods. Contrarily, females had a less cardiac autonomic modulation when comparing the pre-post Wingate test after two consecutive competition periods.
Cellulose Synthase in Atacama Cyanobacteria and Bioethanol Production from Their Exopolysaccharides
(2023) Alexandra Galetović; Gabriel Peña; Nicole Fernández; Milton Urrutia; Nataly Flores; Benito Gómez-Silva; Jocelyne Di Ruggiero; Carolina Shene; Mariela Bustamante
Cyanobacteria produce exopolysaccharides (EPSs) as an adaptative mechanism against ultraviolet radiation and desiccation. Cellulose is present in the extracellular polymeric substance in some cyanobacteria genera and it has been proposed as a raw material for biofuel production. The goal of this work was to evaluate the cellulose presence in EPS of Atacama cyanobacteria strains and its use as an alternative and innovative biological source to produce bioethanol. The presence of cellulose was evaluated using techniques of molecular biology, bioinformatics, and electronic microscopy. The conserved motif D,D,D,35QXXRW, characteristic of processive -glycosyltransferase in all cellulose-producing organisms, was identified in the genome of the LLA-10 strain. This is evidence that cellulose synthase in the LLA-10 strain is a functional enzyme. EPS from Atacama cyanobacteria was hydrolyzed by -glucosidases (cellobiase and cellulase) and the released glucose was yeast-fermented to ethanol. Ethanol production reached 172.69 0.02 mg ethanol/g EPS after 48 h of incubation. These results are the first step in the evaluation of EPS produced by native cyanobacteria isolated from northern Chile for future biotechnological applications such as the production of bioethanol.
Cervical Necrotizing Fasciitis Caused by Oral Cavity Infection: A Case Report Considering Therapeutic Approach and its Morphofunctional Implications
(2023) Cecilia Calderón; Manuel Loo; Fernando Bozán; Carlos Humeres; Alexa Pavez; Iván Valdivia Gandur; Wilson Astudillo Rozas
Cervical necrotizing fasciitis (NF) is a rare complication of oral cavity infection with high morbi-mortality. Given its low prevalence, adequately reporting cases of NF, its therapeutic management, and associated morphofunctional modifications to the clinical and scientific community is pivotal. To that end, we herein describe a case of cervical NF in a 60-year-old patient with comorbidities and patient presented large, painful cervical swelling associated with a necrotic ulcer lesion in the anterior neck region. Intraoral examination indicated a periodontal abscess in the right mandibular area, while computed tomography indicated the lesion’s extension from the right mandibular to the submandibular region. Following empirical intravenous antibiotic treatment, a broad surgical debridement was performed, and the foci of oral infection were removed. Debridement revealed communication between deep and superficial anatomical regions in the submandibular area, where we subsequently placed a Penrose drain. Biopsies showing acute inflammatory infiltrate associated with necrotic and hemorrhagic regions confirmed the diagnosis of NF. When an antibiogram revealed resistance to the empirical treatment, the antibiotic scheme was replaced with an adequate alternative. After a second debridement, we closed the defect with fascio-mucocutaneous advancement flaps with a lateral base while maintaining suction drainage. Having reacted positively, the patient was discharged 10 days after the operation. Despite an extensive morphofunctional change generated in the treated area, the patient showed no difficulties with breathing, phonation, swallowing, or mobilizing the area during control sessions. Altogether, this report contributes to the highly limited literature describing morphological aspects that can facilitate or delay the spread of infection or the morphofunctional disorders associated with the size and depth of surgical interventions for cervical NF, information that is relevant for the comprehensive, long-term prognosis of the treatment of NF.
Characterization of LDLR rs5925 and PCSK9 rs505151 genetic variants frequencies in healthy subjects from northern Chile: Influence on plasma lipid levels
(2019) Claudio Rojas; Hugo Ramírez; Luis A. Salazar; Alexis M. Kalergis; Anita S. Gálvez; Jorge Escobar‐Vera
Background: Identification and characterization of genetic variants and their effects on human health may allow to establish relationships between genetic background and susceptibility to developing cardiovascular diseases. LDLR and PCSK9 polymorphisms have been associated with higher lipid levels and risk of cardiovascular diseases. Thus, the main aim of this study was to evaluate genotype distribution and relative allelic frequency of LDLR rs5925 (1959C > T) and PCSK9 rs505151 (23968 A > G) genetic variants and their effects on lipid levels of healthy subjects from northern Chile. Methods: A total of 178 healthy individuals were recruited for this study. The genotyping of rs5925 (LDLR) and rs505151 (PCSK9) polymorphisms was performed by PCR‐RFLP and qPCR, respectively. In addition, glucose and lipid levels were determined and associated with the genetic data. Results: Genotype distribution for LDLR rs5925 polymorphism was as follows: CC = 19%; CT = 53%; and TT = 28% (HWE: χ2 = 0.80; P = .37), and for PCSK9 rs505151 genetic variant was as follows: AA = 93%; AG = 7%; and GG = 0% (HWE: χ2 = 0.22; P = .64). The frequency of T (rs5925) and G (rs505151) mutated alleles was 0.55 and 0.03, respectively. Data showed that individuals carrying LDLR mutated allele (T) presented lower values of total cholesterol, triglycerides, and LDL‐cholesterol when compared to CC homozygous genotype (P < .05). Subgroup analysis revealed that women carrying the PCSK9 mutated allele (G) exhibited higher values of total cholesterol, triglycerides, HDL‐C, and LDL‐C when compared to male group carrying the same genotype (P<05). Conclusions: The effect of LDLR rs5925 and PCSK9 rs505151 gene polymorphisms on lipid levels is associated with gender among healthy subjects from northern Chile.
Chemical Profiling, Antioxidant, Anticholinesterase, and Antiprotozoal Potentials of Artemisia copa Phil. (Asteraceae)
(2020) Maria José Larrazábal-Fuentes; Carlos Fernández-Galleguillos; Jenifer Palma-Ramírez; Javier Romero-Parra; Kevin Sepúlveda; Jorge González; Adrián Paredes; Jorge Bórquez; Mario J. Simirgiotis; Javier Echeverría; Alexandra Galetović
Artemisia copa Phil. (Asteraceae) (known as copa-copa) is a native species of Chile used as an infusion in traditional medicine by Atacameños people in the Altiplano, highlands of northern Chile. In this research, we have investigated for the first time the cholinesterase inhibition potential against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), and the chemical profiling of the infusions prepared from the aerial parts of A. copa by high resolution spectrometry. In addition, total phenolic, total flavonoid content, antioxidant (DPPH, FRAP, and ORAC) and antiprozoal activity were tested. Artemisia copa showed good inhibitory activity against AChE and BChE (3.92 ± 0.08 µg/ml and 44.13 ± 0.10 µg/ml). The infusion displayed a total phenolics content of 155.6 ± 2.9 mg of gallic acid equivalents/g and total flavonoid content of 5.5 ± 0.2 mg quercetin equivalents/g. Additionally, trypanocidal activity against Trypanosoma cruzi was found (LD50 of 131.8 µg/ml). Forty-seven metabolites were detected in the infusion of A. copa including several phenolic acids and flavonoids which were rapidly identified using ultrahigh performance liquid chromatography orbitrap mass spectrometry analysis (UHPLC-Orbitrap-MS) for chemical profiling. The major compounds identified in the infusions were studied by molecular docking against AChE and BChE. The UHPLC-MS fingerprints generated can be also used for the authentication of these endemic species. These findings reveal that A. copa infusions can be used as beverages with protective effects.
Climate variability in a 3.8 Ma old sedimentary record from the hyperarid Atacama Desert
(2024) Felix L. Arens; Jenny Feige; Alessandro Airo; Christof Sager; Lutz Hecht; Lucas Horstmann; Felix E.D. Kaufmann; Johannes Lachner; Thomas Neumann; Norbert Nowaczyk; Ferry Schiperski; Peter Steier; Alexandra Stoll; Ulrich Struck; Bernardita Valenzuela; Friedhelm von Blanckenburg; Hella Wittmann; Lukas Wacker; Dirk Wagner; Pedro Zamorano; Dirk Schulze Makuch
The hyperarid Atacama Desert is one of the driest and oldest deserts on Earth, rendering it a valuable climate archive. However, unraveling its past climate is particularly challenging and the few studied paleoclimate records of the region reveal strong temporal and spatial variabilities. To enhance our understanding of these dynamics we investigated a sedimentary record in the Yungay valley located in the southern hyperarid Atacama Desert. We employed paleomagnetic and radiocarbon dating, and for the first time for Atacama Desert sediments, a meteoric 10Be/9Be based method for determining the depositional age. The respective 4.20 m deep profile comprises a lower alluvial fan deposit with a maximum age of 3.8 ± 0.8 Ma, and an upper 1.84 m thick clay pan deposit that has accumulated over the last 19 ka. Different proxies including grain size, salt concentration, and elemental composition indicate an aridity increase around 2.3 Ma ago and repeated dry and wet phases during the late Pleistocene and the Holocene. The latter climatic shifts can be assigned to variabilities of the South American Summer Monsoon and El Niño Southern Oscillation with moisture sources from the Atlantic and the Pacific Ocean, respectively. This study provides deeper insights into the heterogeneous climate of the hyperarid Atacama Desert and underlines the importance of interdisciplinary investigations to decipher climate systems and their effect on potential habitable regions in such an extreme environment.
Comparison of Total Anaerobic Microbiota in Periodontitis Before and After the Subgingival Irrigation with Chlorhexidine at 0.12 %
(2019) Lorena Mejías; Diego Iriarte; Rodolfo Sanchez; Iván Neira; Joel Bravo
El objetivo del presente estudio fue determinar el efecto de la irrigaci n subgingival de la clorhexidina 0,12 % sobre la microbiota anaer bica total. Se tomaron muestras microbiol gicas a 30 sujetos con periodontitis estadio II grado B, en sacos periodontales con una profundidad de sondaje > 4 mm. Se realizó la irrigación subgingival con 5 mL. de clorhexidina en el grupo test y con 5 mL. de agua destilada en el grupo control. 24 horas después del procedimiento se obtuvo una segunda muestra a comparar. Se detectó que la irrigación subgingival con clorhexidina al 0,12 % logra disminuir en forma estadísticamente significativa la microbiota anaeróbica total (p< 0,05).
Complications post simple exodontia: A systematic review
(2022) Víctor Herrera Barraza; Sofía Arroyo Larrondo; Melissa Fernández-Córdova; Daniela Catricura Cerna; Constanza Garrido Urrutia; Nicolás Ferrer Valdivia
Exodontia procedures are not without complications, which are the dentist’s responsibility to avoid by taking into account clinical, imaging, systemic, and operative factors, among others. The purpose of this systematic review is to determine and analyze the prevalence of complications post simple exodontia (CPES). The method used in this systematic review was adapted from the Cochrane Handbook and PRISMA statement. A systematic search was conducted in PubMed, Scopus and ScienceDirect using the search terms “Exodontia” AND “Complications”. The search was conducted from the starting coverage date to January 31, 2020. The inclusion criteria were studies on simple exodontia, studies on CPES prevalence and human studies. Studies on complications after third molar exodontia, generalities in exodontia, narratives and systematics literature reviews, book chapters, and animal studies were excluded. A total of 1,446 articles were found in the first search using the search strategy (725 in PubMed, 96 in Scopus and 631 in ScienceDirect). After duplicates were removed, 948 articles were obtained. After reading the title and abstract, 9 articles were read in full. Finally, 3 articles were included in the review, with the most common complications being trismus, alveolitis, pain, dehiscence, infections, and retained roots. Trismus of the chewing muscles, alveolitis and retained roots were the most prevalent CPES, which were most likely related to the surgeon’s experience, surgery duration and tissue trauma during surgery.
Consequences of Exposure to Hypobaric Hypoxia Associated with High Altitude on Spermatogenesis and Seminal Parameters: A Literature Review
(2024) Carlos Cornejo Guerra; Camila Salazar Ardiles; Patricio Morales; David C. Andrade
Preclinical research has provided compelling evidence indicating that exposure to hypobaric hypoxia (HH) results in a deterioration of spermatogenesis. This adverse effect extends to the underlying molecular mechanisms, progressively leading to impairments in the seminiferous epithelium and germ cells and alterations in semen parameters. Indeed, several studies have demonstrated that animals exposed to HH, whether in natural high-altitude environments or under simulated hypoxic conditions, exhibit damage to the self-renewal and differentiation of spermatogenesis, an increase in germline cell apoptosis, and structural alterations in the seminiferous tubules. One of the primary mechanisms associated with the inhibition of differentiation and an increase in apoptosis among germ cells is an elevated level of oxidative stress, which has been closely associated with HH exposure. Human studies have shown that individuals exposed to HH, such as mountaineers and alpinists, exhibit decreased sperm count, reduced motility, diminished viability, and increased sperm with abnormal morphology in their semen. This evidence strongly suggests that exposure to HH may be considered a significant risk factor that could elevate the prevalence of male infertility. This literature review aims to provide a comprehensive description and propose potential mechanisms that could elucidate the infertility processes induced by HH. By doing so, it contributes to expanding our understanding of the challenges posed by extreme environments on human physiology, opening new avenues for research in this field.
Contribution of Fcy Receptor-Mediated Immunity to the Pathogenesis Caused by the Human Respiratory Syncytial Virus
(2019) Orlando A. Acevedo; Fabián E. Díaz; Tomas E. Beals; Felipe M. Benavente; Jorge A. Soto Pablo A. González Alexis M. Kalergis; Jorge Escobar Vera; Pablo A. González; Alexis M. Kalergis
The human Respiratory Syncytial Virus (hRSV) is the leading cause of severe acute lower respiratory tract infections (ALRTIs) in humans at all ages and is the main cause of hospitalization due to pneumonia, asthma, and bronchiolitis in infants. hRSV symptoms mainly develop due to an excessive host immune and inflammatory response in the respiratory tissue. hRSV infection during life is frequent and likely because of non-optimal immunological memory is developed against this virus. Vaccine development against this pathogen has been delayed after the detrimental effects produced in children by vaccination with a formalin-inactivated hRSV preparation (FI-hRSV), which caused enhanced disease upon natural viral infection. Since then, several studies have focused on understanding the mechanisms underlying such disease exacerbation. Along these lines, several studies have suggested that antibodies elicited by immunization with FI-hRSV show low neutralizing capacity and promote the formation of immune complexes containing hRSV (hRSV-ICs), which contribute to hRSV pathogenesis through the engagement of Fc gamma receptors (FcγRs) expressed on the surface of immune cells. Furthermore, a role for FcγRs is supported by studies evaluating the contribution of these molecules to hRSV-induced disease. These studies have shown that FcγRs can modulate viral clearance by the host and the inflammatory response triggered by hRSV infection. In addition, ICs can facilitate viral entry into host cells expressing FcγRs, thus extending hRSV infectivity. In this article, we discuss current knowledge relative to the contribution of hRSV-ICs and FcγRs to the pathogenesis caused by hRSV and their putative role in the exacerbation of the disease caused by this virus after FI-hRSV vaccination. A better understanding FcγRs involvement in the immune response against hRSV will contribute to the development of new prophylactic or therapeutic tools to promote virus clearance with limited inflammatory damage to the airways
Deep Learning-Based Glucose Prediction Models: A Guide for Practitioners and a Curated Dataset for Improved Diabetes Management
(2024) SAÚL LANGARICA; DIEGO DE LA VEGA; NAWEL CARIMAN; MARTÍN MIRANDA; DAVID C. ANDRADE; FELIPE NÚÑEZ; MARIA RODRIGUEZ-FERNANDEZ
Accurate short- and mid-term blood glucose predictions are crucial for patients with diabetes struggling to maintain healthy glucose levels, as well as for individuals at risk of developing the disease. Consequently, numerous efforts from the scientific community have focused on developing predictive models for glucose levels. This study harnesses physiological data collected from wearable sensors to construct a series of data-driven models based on deep learning approaches. We systematically compare these models to offer insights for practitioners and researchers venturing into glucose prediction using deep learning techniques. Key questions addressed in this work encompass the comparison of various deep learning architectures for this task, determining the optimal set of input variables for accurate glucose prediction, comparing population-wide, fine-tuned, and personalized models, and assessing the impact of an individual’s data volume on model performance. Additionally, as part of our outcomes, we introduce a meticulously curated dataset inclusive of data from both healthy individuals and those with diabetes, recorded in free-living conditions. This dataset aims to foster research in this domain and facilitate equitable comparisons among researchers.
Detraining’s Effects on Cardiorespiratory Fitness and Maximal and Explosive Strength in Army Soldiers: Does Age Matter?
(2024) Alexis Arce Álvarez; Ángelo Zaio; Camila Salazar Ardiles; Cristian Álvarez; Pablo Merino Muñoz; Manuel Vasquez-Muñoz; Mikel Izquierdo; Mauricio Castro; David C. Andrade
Purpose: This study investigated the impact of four weeks of age-dependent detraining on army soldiers’ cardiorespiratory fitness and maximal and explosive strength. Methods: Fourteen volunteer tactical athletes participated, divided into two age groups (20 to 29 and 30 to 40 years). Before and after the detraining period, we assessed their anthropometric measurements (weight, height, body mass index, fat mass, and fat-free mass), cardiorespiratory fitness (maximal oxygen uptake [VO2max] and ventilatory thresholds [VT1 and VT2]), and kinematic properties during a single-leg counter-moving jump (CMJ) test for both the dominant and non-dominant legs. Two-way ANOVA followed by the Holm–Sidak post hoc test was used. Results: The anthropometric and cardiovascular variables did not show significant differences between the groups. However, both groups exhibited a significantly reduced maximum time and speed at the VO2max. Furthermore, the flight time and maximum height during the CMJ significantly decreased in the non-dominant leg for both age groups. Notably, the dominant leg’s concentric impulse (CI) significantly reduced during the CMJ, but this effect was observed only in the 30–40 age group. There were significant differences between the two age groups. Conclusions: Our findings suggest that four weeks of detraining negatively impacts aerobic fitness and muscular strength, independently of age. However, the dominant leg may be more susceptible to detraining effects in army soldiers aged 30–40. Furthermore, as a perspective, our results strongly suggest that a detraining period could affect successful missions (aerobic performance deterioration), as well as promote a muscle imbalance between the legs, which could encourage muscle injuries and endanger combat missions.
Development of a Bicistronic Vector for the Expression of a CRISPR/Cas9-mCherry System in Fish Cell Lines
(2019) Sebastian Escobar Aguirre; Duxan Arancibia; Amanda Escorza; Cristián Bravo; María Estela Andrés; Pedro Zamorano; Víctor Martínez
The clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system has been widely used in animals as an efficient genome editing tool. In fish cells, the technique has been difficult to implement due to the lack of proper vectors that use active promoters to drive the expression of both small guide RNA (sgRNA) and the S. pyogenes Cas9 (spCas9) protein within a single expression platform. Until now, fish cells have been modified using co-transfection of the mRNA of both the sgRNA and the spCas9. In the present study, we describe the optimization of a new vector for the expression of a CRISPR/Cas9 system, designed to edit the genome of fish cell lines, that combines a gene reporter (mCherry), sgRNA, and spCas9 in a single vector, facilitating the study of the efficiency of piscine and non-piscine promoters. A cassette containing the zebrafish U6 RNA III polymerase (U6ZF) promoter was used for the expression of the sgRNA. The new plasmid displayed the expression of spCas9, mCherry, and sgRNA in CHSE/F fish cells. The results demonstrate the functionality of the mammalian promoter and the U6ZF promoter in fish cell lines. This is the first approach aimed at developing a unified genome editing system in fish cells using bicistronic vectors, thus creating a powerful biotechnological platform to study gene function
Differential Activity and Expression of Proteasome in Seminiferous Epithelium During Mouse Spermatogenesis
(2025) Héctor Zapata Carmona; Emilce Silvina Díaz; Patricio Morales; Marco Jara
Proteasome-mediated protein degradation is essential for maintaining cellular homeostasis, particularly during spermatogenesis, where extensive cellular transformations, such as spermatid differentiation, require precise protein turnover. A key player in this process is the ubiquitin–proteasome system (UPS). This study aimed to investigate proteasome enzymatic activity at different stages of the spermatogenic cycle within the seminiferous tubules of mice and explore the regulatory mechanisms that influence its proteolytic function. Specifically, we assessed the trypsin-like, chymotrypsin-like, and peptidyl-glutamyl-peptide-hydrolyzing (PGPH) activities of the proteasome. Additionally, we examined the expression of catalytic and structural subunits of the 20S core, the assembly of the 20S core with regulatory complexes, and the phosphorylation status of proteasome subunits in various segments of the seminiferous tubules. Our findings demonstrated distinct patterns of proteasomal enzymatic activity in the analyzed segments. While the expression levels of structural and catalytic subunits of the 20S core remained consistent, significant differences were detected in the assembly of the 20S core, the expression of regulatory complexes, and the phosphorylation of proteasome subunits mediated by protein kinase A. These results indicate that proteasomal activity is finely regulated through multiple mechanisms depending on the specific stage of the seminiferous epithelial cycle, highlighting the complexity of proteostasis during spermatogenesis.

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