Repositorio Académico de la Universidad Católica del Maule
Not a member yet
5788 research outputs found
Sort by
The TRPV3 channel is a mediator of zinc influx and homeostasis in murine oocytes
No full textZinc (Zn2+) homeostasis is essential for gametogenesis and reproduction, and its deficiency causes infertility. Oocytes contain higher Zn2+ levels than somatic cells, and Zn2+ concentrations in oocytes are far higher than those of other transition metals and increase even more during maturation in preparation for fertilization. Remarkably, it is unknown what transporter(s) or channel(s) mediate Zn2+ influx in oocytes and whether they are expressed uniformly throughout folliculogenesis. Here, we showed that the functional expression of a member of the transient receptor potential family, vanilloid 3, TRPV3, closely follows the dynamics of intracellular Zn2+ during oocyte maturation, raising the prospect that these events may be functionally linked. Using microfluorometry, we monitored in oocytes of Trpv3 null females the expected rise in Zn2+ concentrations during maturation. Surprisingly, Zn2+ levels did not climb, and the overall FluoZin3 signal in Trpv3 null eggs was lower than in control eggs. Electrophysiological recordings showed a large TRPV3 current induced by the agonist 2-APB in WT eggs supplemented with extracellular Zn2+ that was absent in Trpv3 null eggs; TRPV3 showed a clear preference for Zn2+ over Ca2+. Trpv3 null eggs displayed features associated with Zn2+ deficient conditions, such as lower IP3R1 function, abnormal cortical granule distribution, and disturbed cytoskeletal organization with distinct actin nucleation disorders. Notably, Trpv3 null eggs demonstrated undisturbed Zn2+ sparks. Our results suggest that TRPV3 is a pivotal member of the Zn2+ toolkit, mediating Zn2+ intake during maturation. They also indicate that distinct transporters or channels mediate Zn2+ influx throughout folliculogenesis
Effectiveness of combined cognitive stimulation and physical activity interventions on activities of daily living, cognitive function, and physical function in older people with mild cognitive impairment: a systematic review with meta-analysis
No full textBackground/Objectives: This systematic review with meta-analysis aimed to evaluate and synthesize scientific evidence about the combined cognitive stimulation and physical activity interventions on Activities of Daily Living (ADL), cognitive function, and physical function in older people with Mild Cognitive Impairment (MCI). Methods: A systematic literature search was conducted between August 2024 and October 2024 using the core collection of six generic databases: PubMed, EBSCOhost, CINAHL Complete, Cochrane, Scopus, and Web of Science. The PRISMA, RoB 2, and GRADEpro tools assessed the evidence’s methodological quality and certainty. The protocol was registered in PROSPERO, CRD42024577229. Results: Of 270 records identified in the databases, 9 studies were analyzed using the PICOS format. The MMSE meta-analysis showed significant improvements in cognitive function in favor of the experimental groups (p = 0.010). In contrast, no significant improvements were found for TMT-A (p = 0.51) and TMT-B (p = 0.37). No significant differences were reported for the other variables studied. Conclusions: Cognitive function, as measured by the MMSE, showed significant improvements, while the interventions analyzed did not produce significant improvements in ADL or physical function among older people with MCI. Individual studies suggest that programs that integrate both cognitive stimulation and physical activity components may provide some benefits
You are as old as the connectivity you keep: distinct neurophysiological mechanisms underlying age-related changes in hand dexterity and strength
No full textBackground
Aging can lead to a decline in motor control. While age-related motor impairments have been documented, the underlying changes in cortico-cortical interactions remain poorly understood.
Methods
We took advantage of the high temporal resolution of dual-site transcranial magnetic stimulation (dsTMS) to investigate how communication between higher-order rostral premotor regions and the primary motor cortex (M1) influences motor control in young and elderly adults. We assessed the dynamics of connectivity from the inferior frontal gyrus (IFG) or pre-supplementary motor area (preSMA) to M1, by testing how conditioning of the IFG/preSMA affected the amplitude of motor evoked potentials (MEPs) induced by M1 stimulation at different temporal intervals. Moreover, we explored how age-related changes in premotor-M1 interactions relate to motor performance.
Results
Our results show that both young and elderly adults had excitatory IFG-M1 and preSMA-M1 interactions, but the two groups’ timing and strength differed. In young adults, IFG-M1 interactions were early and time-specific (8 ms), whereas in older individuals, they were delayed and more prolonged (12-16 ms). PreSMA-M1 interactions emerged early (6 ms) and peaked at 10-12 ms in young individuals but were attenuated in older individuals. Critically, a connectivity profile of the IFG-M1 circuit like that of the young cohort predicted better dexterity in older individuals, while preserved preSMA-M1 interactions predicted greater strength, suggesting that age-related motor decline is associated with specific changes in premotor-motor networks.
Conclusions
Preserving youthful motor network connectivity in older individuals is related to maintaining motor performance and providing information for interventions targeting aging effects on behavior
Photocatalytic degradation of organic dyes and binary mixture of dyes by Fe and Cu doped ZnO nanoparticles under artificial light and sunlight
No full textThe objective of this work was to utilize Zinc Oxide (ZnO) nanoparticles doped with 4 wt% Cu and varying concentrations of Fe (2, 3, 4, and 8 wt%) as efficient photocatalysts for dye degradation. The synthesized 2FCZ, 3FCZ, 4FCZ, and 8FCZ nanoparticles were tested on various dyes (Methylene Blue (MB), Rhodamine B (RhB), Rose Bengal (RB), Brilliant Yellow (BY), Acid Red (AR)) and their binary mixtures under artificial light and sunlight. Using 1 mg of catalyst and 1 mL of H2O2 for 100 mL of 10 ppm dye solution, 4FCZ showed the highest degradation efficiency. In an artificial reactor, it achieved 98.1 %, 94.8 %, 48 %, 65.6 %, and 21 % for the respective dyes, and in sunlight, 88.7 %, 75.3 %, 78.7 %, 52 %, and 27 %. 4FCZ demonstrated better performance in the artificial photoreactor. The catalyst’s selectivity was confirmed using binary dye mixtures, and its efficiency was attributed to the generation of radical dotOH radicals and inhibition of e−/h+ recombination. A key advantage is the minimal catalyst and H2O2 required, making this method promising for large-scale wastewater treatment, particularly in the textile industry
Effects of resisted sled training on sprint performance in team sports. a systematic review and meta-analysis
No full textObjective
This systematic review and meta-analysis aimed to examine the effects of resistance sled training (RST) on sprint performance in team sport athletes.
Methods
A systematic search was conducted in the electronic databases MEDLINE, Sportdiscus, Scopus and Web of Science from inception until October 2023. Randomized or non-randomized controlled clinical trials that included collective field sports athletes who were trained with sled drag were included to evaluate the effectiveness of the training on performance in speed tests. Independent reviewer selected the studies with www.rayyan.ai, extracted the data, performed the risk-of-bias assessment, and methodological quality. The sprint time at distances of 5, 10 and 20 m were included for the meta-analysis. A random-effects model, standardized mean difference, and standard deviation were used for meta-analysis.
Results
Fourteen studies involving 344 participants were selected (overall risk: high risk; methodological quality: moderate quality). Meta-analysis revealed statistically significant effects in favor of RST on 5 m (SMD = −0.87; 95% CI = −1.58 to −0.16; p = 0.02) and 10 m (SMD = −0.40; 95% CI = −0.78 to −0.03; p = 0.04). However, there are no significant effects on 20 m (SMD = −0.34; 95% CI = −0.73 to 0.06 p = 0.1).
Conclusion
These results indicate that RST improves performance mainly in the short distance, suggesting that RST is a viable training method to improve athletic performance in team sports
Metacognition in mathematical modeling tasks with primary school students in Chile
No full textEste artículo de investigación presenta la caracterización de las estrategias metacognitivas y experiencias socioemocionales que activan los estudiantes de educación primaria cuando resuelven tareas de modelado matemático. Se utilizó una metodología cualitativa con estudio de casos múltiple de alcance exploratorio. Se seleccionaron dos grupos de trabajo de 1° y 3° grado para observar en profundidad las estrategias y experiencias metacognitivas que activan los niños cuando resuelven tareas mediante un trabajo colaborativo grupal. Se usaron grabaciones de video mientras resolvían las tareas de modelado y se codificaron en Atlas ti. Para el análisis, se utilizaron sistemas de categorías en las estrategias metacognitivas y experiencias socioemocionales y se cruzaron con las fases del ciclo de modelado. Como resultados del análisis los niños de 1° grado activaron las estrategias de proceder en las primeras etapas del ciclo de modelado y los de 3°grado las estrategias de planificar y monitorear en las fases de simplificación, matematización y trabajo matemático. Las mayores sensaciones de agrado, desánimo y descontrol, se generan en estas fases. Ambos grupos regulan sus reacciones emocionales para persistir en la tarea, controlándose para evitar distracciones del equipo. Las estrategias de regular se activaron en la fase de matematización para ambos grupos y en el trabajo matemático en el grupo de 3°grado y, las estrategias de evaluar en la interpretación de soluciones y validación del modelo para ambos grupos. En el grupo de 3° grado emergen sensaciones de agrado y desconcierto cuando proyectan el modelo detectando fortalezas y limitaciones
Training self-other distinction: effects on emotion regulation, empathy, and theory of mind
No full textNavigating our social environment requires the ability to distinguish ourselves from others. Previous research suggests that training interventions have the potential to enhance the capacity for self–other distinction (SOD), which then may impact various sociocognitive domains, including imitation–inhibition, visual perspective taking, and empathy. Importantly, empirical research on the role of SOD in emotion regulation remains scarce. In this study, we aim to investigate the impact of training SOD on emotion regulation and also replicate findings on empathy and the attribution of mental states to others. Using a pre–post design, participants (N = 104) were assigned to either the imitation–inhibition or general inhibitory control training. Compared to general inhibitory control training, participants trained to inhibit imitation displayed a significant increase in posttest emotion regulation levels compared to pretest levels, indicating that imitation–inhibition training increased self-reported emotion regulation. Notably, emotional interference remained unaffected by either form of training. Both training interventions resulted in diminished self-reported empathic concern, while only general inhibitory control training led to a reduction in personal distress. Moreover, neither type of training had an impact on self-reported perspective taking or theory of mind performance. This study provides novel empirical evidence of the positive impact of imitation–inhibition training on emotion regulation. Furthermore, our findings make significant contributions to the advancement of research in this area and offer further support for the advantages of behavioral training as a methodological approach to studying sociocognitive abilities. (PsycInfo Database Record (c) 2025 APA, all rights reserved
Shoulder pain among type 2 diabetes mellitus patients: a cross-sectional study in Chilean population
No full textAim
This study aimed determine the prevalence of shoulder pain among Chilean patients with type 2 DM and to characterize their pain intensity and associated disabilities, including an analysis of sex-based differences.
Methods
A total of 151 participants with type 2 DM, aged 18–79, from family health centers in Talca, Chile, were included. Data were collected via telephone interview, capturing demographic details and information about current shoulder pain, including its duration, intensity, using a Numerical Rating Scale (NRS), and disability using the Shoulder Pain and Disability Index (SPADI). Statistical analysis was performed using frequency measures, Chi-squared tests, binary logistic regression, and Student's t-tests with SPSS version 21.0.
Results
Out of 1662 eligible patients, 151 participated. The overall prevalence of shoulder pain was 53.6 % (95 % CI: 53.8–53.4), with women showing a higher prevalence (63 %; 95 % CI: 63.2–62.8) compared to men (37 %; 95 % CI: 37.2–36.8), a difference that was statistically significant (chi-square=13.5; p ≤ 0.001). The results showed that neither BMI nor sex was significantly associated with the presence of pain. No significant differences were found between sexes regarding pain intensity and disability (p ≥ 0.05).
Conclusion
Shoulder pain is highly prevalent among patients with type 2 DM, with a higher prevalence in women. Future research should explore the impact of this condition on patients and develop targeted musculoskeletal rehabilitation programs
Pollination of endangered Philodendron cipoense (Araceae): floral scent ensures the attraction of several specialized cyclocephaline beetle species (Melolonthidae, Cyclocephalini)
No full textThe remarkable species richness of the Neotropical aroid genus Philodendron (Araceae) is closely linked to its specialized nocturnal pollination system, where chemically distinct floral scents selectively attract night-active cyclocephaline beetles (Melolonthidae, Cyclocephalini). This study explores the floral biology and chemical ecology of Philodendron cipoense, an endangered, rupicolous species endemic to Brazil’s Espinhaço mountain range in the Campo Rupestre. Through qualitative and quantitative analyses of floral scent chemistry and field experiments, we assessed the role of key volatile organic compounds (VOCs) in pollinator attraction. P. cipoense relies heavily on pollinators and attracted a diverse assemblage of specialized beetles, including Cyclocephala atricapilla, C. variolosa, Chalepides dilatatus, and Erioscelis sp. Its floral scent is dominated by (Z)-jasmone, 4-vinylanisole, and isojasmol, collectively accounting for 97% of total emissions. Field experiments confirmed the attractiveness of (Z)-jasmone, successfully luring a male of C. atricapilla (pollinator) and C. celata (non-pollinator) individuals of both sexes. These findings underscore the pivotal role of floral scent as an olfactory cue in pollinator attraction, revealing asymmetrical mutualisms and interdependence between P. cipoense and its pollinators. Our results provide valuable insights for conservation strategies and targeted action plans to protect this threatened species
Higher education and social responsibility: training needs of graduates in administrative, accounting, and economic sciences
No full textEl objetivo de esta investigación es analizar la responsabilidad social profesional (RSP) de titulados en ciencias administrativas, económicas y contables en Chile. Se aplica un instrumento a una muestra no probabilística compuesta por 137 profesionales. La metodología es de carácter exploratorio y se aplica un instrumento validado. Se realiza un análisis factorial exploratorio y se examinan diferencias estadísticamente significativas. Los resultados demuestran diferencias según: sexo, voluntariado y organización social. Las universidades deben implementar políticas educativas que incluyan los valores de la responsabilidad social en consistencia con los perfiles profesionales en coherencia con las necesidades de las empresas modernas. En conclusión, los resultados de esta investigación deben ser usados por instituciones de educación superior (IES) de acuerdo a las características de la disciplina profesional y la singularidad de los requerimientos de los grupos de interés que habitan sus territorios de influencia