A Dynamic Fitting Strategy for Physiological Models: A Case Study of a Cardiorespiratory Model for the Simulation of Incremental Aerobic Exercise.

Using mathematical models of physiological systems in medicine has allowed for the development of diagnostic, treatment, and medical educational tools. However, their complexity restricts, in most cases, their application for predictive, preventive, and personalized purposes. Although there are strategies that reduce the complexity of applying models based on fitting techniques, most of them are focused on a single instant of time, neglecting the effect of the system's temporal evolution. The objective of this research was to introduce a dynamic fitting strategy for physiological models with an extensive array of parameters and a constrained amount of experimental data. The proposed strategy focused on obtaining better predictions based on the temporal trends in the system's parameters and being capable of predicting future states. The study utilized a cardiorespiratory model as a case study. Experimental data from a longitudinal study of healthy adult subjects undergoing aerobic exercise were used for fitting and validation. The model predictions obtained in a steady state using the proposed strategy and the traditional single-fit approach were compared. The most successful outcomes were primarily linked to the proposed strategy, exhibiting better overall results regarding accuracy and behavior than the traditional population fitting approach at a single instant in time. The results evidenced the usefulness of the dynamic fitting strategy, highlighting its use for predictive, preventive, and personalized applications.

Optimization of 3D Synthetic Scaffolds for Neuronal Tissue Engineering Applications.

The increasing prevalence of neurodegenerative diseases has spurred researchers to develop advanced 3D models that accurately mimic neural tissues. Hydrogels stand out as ideal candidates as their properties closely resemble those of the extracellular matrix. A critical challenge in this regard is to comprehend the influence of the scaffold's mechanical properties on cell growth and differentiation, thus enabling targeted modifications. In light of this, a synthesis and comprehensive analysis of acrylamide-based hydrogels incorporating a peptide has been conducted. Adequate cell adhesion and development is achieved due to their bioactive nature and specific interactions with cellular receptors. The integration of a precisely controlled physicochemical hydrogel matrix and inclusion of the arginine-glycine-aspartic acid peptide sequence has endowed this system with an optimal structure, thus providing a unique ability to interact effectively with biomolecules. The analysis fully examined essential properties governing cell behavior, including pore size, mechanical characteristics, and swelling ability. Cell-viability experiments were performed to assess the hydrogel's biocompatibility, while the incorporation of grow factors aimed to promote the differentiation of neuroblastoma cells. The results underscore the hydrogel's ability to stimulate cell viability and differentiation in the presence of the peptide within the matrix.

Morphologic Differentiation of the Exotic Parasitoid Eupelmus pulchriceps (Hymenoptera: Eupelmidae) in the Galapagos Archipelago.

The historical and geographical properties of the archipelagos allow a detailed study of species diversification, and phenotypic traits can indicate the extent of such processes. Eupelmus pulchriceps (Cameron, 1904) is an exotic species to the Galapagos archipelago, and generalist parasitoid that attacks a beetle species that consumes the seeds of the invasive shrub Leucaena leucocephala (Lam.) de Wit. Despite extensive sampling, the wasp is recorded only in Santa Cruz and San Cristobal islands of the Galapagos archipelago. Thus, using 112 female wasps, we compare body size, proportion, and allometric differentiations within and between the two islands. There were no body size differences between islands. A PerMANOVA indicates differences between the islands and a single differentiation between two localities of one island. Allometric differences between islands were not the same for all structures. These results are consistent with the greater distance between islands than between localities and suggest a differentiation process. The variables with allometric differentiation are associated with wings and ovipositor, possibly responding to different ecological pressures. It is interesting that this parasitoid, recently arrived at the archipelago, is already showing differentiation. Also, it is essential to monitor the behavior of these wasps in the archipelago, given their potential to access other species affecting the trophic interactions of the local biota.

A new genus and five new species of pseudoscorpions (Arachnida, Pseudoscorpiones, Withiidae) from Colombia.

The pseudoscorpion family Withiidae is widely distributed around the world, with most of its diversity in tropical areas. Five new species and a new genus from Colombia are described: Cystowithiusflorezisp. nov., Parawithiusbromelicolasp. nov., Oligowithiusachaguasp. nov., and the genus Paciwithiusgen. nov. with two species Paciwithiusvalduparensissp. nov. and Paciwithiuschimbilacussp. nov. A reassessment of the subgenus Dolichowithius (Oligowithius) Beier, 1936 allows the elevation to a full generic level, and the transfer of the only known species to Oligowithius, forming the new combination Oligowithiusabnormis (Beier, 1936), comb. nov.

Mimicking the extracellular matrix by incorporating functionalized graphene into hybrid hydrogels.

The efficient functionalization of graphene with sulfonic groups using a sustainable approach facilitates the interaction of biomolecules with its surface. The inclusion of these graphene sheets inside a photopolymerized acrylamide-based hydrogel provides a 3D scaffold with viscoelastic behaviour closer to that found in natural tissues. Cell-culture experiments and differentiation assays with SH-SY5Y cells showed that these hybrid hydrogels are non-cytotoxic, thus making them potentially useful as scaffold materials mimicking the extracellular environment.

Microlearning through TikTok in Higher Education. An evaluation of uses and potentials.

While social media is evolving rapidly, understanding its underlying and persistent features with the potential to support high-quality learning would provide opportunities to enhance competence acquisition and collaborative work in higher education. Moreover, the adoption of tools that students already use in their everyday lives facilitates the integration of new forms of learning. In this context, we have developed an initiative to disseminate content through TikTok in three modules of the Bachelor's Degree in Nursing course, with the aim of promoting quality learning through these microlearning environments. To this end, we have implemented these learning environments and evaluated the users' perceptions, as well as their level of acceptance of the technology according to the Technology Acceptance Model. Overall, our results show high levels of satisfaction with regard to engagement and the content generated, as well as in terms of the acceptance of the technology. Our results do not show gender-specific variations, but we did detect slight variations depending on the subject in which the microlearning tool was deployed. Although for the most part these variations do not change the participants' assessment of their experience, it will be necessary in the future to determine the underlying reasons for these variations. In addition, our results suggest that it is possible to design a content creation system to promote quality learning through microlearning that can be transferred to other subjects, at least in the Bachelor's Degree in Nursing. Supplementary Information: The online version contains supplementary material available at 10.1007/s10639-023-11904-4.

A Novel Strategy to Fit and Validate Physiological Models: A Case Study of a Cardiorespiratory Model for Simulation of Incremental Aerobic Exercise.

Applying complex mathematical models of physiological systems is challenging due to the large number of parameters. Identifying these parameters through experimentation is difficult, and although procedures for fitting and validating models are reported, no integrated strategy exists. Additionally, the complexity of optimization is generally neglected when the number of experimental observations is restricted, obtaining multiple solutions or results without physiological justification. This work proposes a fitting and validation strategy for physiological models with many parameters under various populations, stimuli, and experimental conditions. A cardiorespiratory system model is used as a case study, and the strategy, model, computational implementation, and data analysis are described. Using optimized parameter values, model simulations are compared to those obtained using nominal values, with experimental data as a reference. Overall, a reduction in prediction error is achieved compared to that reported for model building. Furthermore, the behavior and accuracy of all the predictions in the steady state were improved. The results validate the fitted model and provide evidence of the proposed strategy's usefulness.

The interactions of alcohol and cocaine regulate the expression of genes involved in the GABAergic, glutamatergic and endocannabinoid systems of male and female rats.

Although the pharmacological and behavioural interactions between cocaine and alcohol are well established, less is known about how polyconsumption of these drugs affects the neurotransmitter systems involved in their psychoactive effects and in particular, in the process of addiction. Here, rats of both sexes at two stages of development were studied under a chronic regime of intravenous cocaine and/or alcohol administration. Brain samples from the medial prefrontal cortex, nucleus accumbens, hippocampus and amygdala were extracted to analyse the mRNA expression of genes encoding subunits of the GABA, NMDA and AMPA receptors, as well as the expression of the CB1 receptor, and that of enzymes related to the biosynthesis and degradation of endocannabinoids. Moreover, two synaptic scaffold proteins related to GABA and NMDA receptors, gephyrin and PSD-95, were quantified in Western blots. Significant interactions between cocaine and alcohol were common, affecting the GABAergic and endocannabinoid systems in the medial prefrontal cortex and amygdala of young adults, whereas such interactions were evident in the glutamatergic and endocannabinoid systems in adults, as well as a more pronounced sex effect. Significant interactions between these drugs affecting the scaffold proteins were evident in the medial prefrontal cortex and nucleus accumbens of young adults, and in the nucleus accumbens and amygdala of adults, but not in the hippocampus. These results highlight the importance of considering the interactions between cocaine and alcohol on neurotransmitter systems in the context of polyconsumption, specifically when treating problems of abuse of these two substances.

Rationale and Methods of Evaluation for ACHO, A New Virtual Assistant to Improve Therapeutic Adherence in Rural Elderly Populations: A User-Driven Living Lab.

Low therapeutic adherence is a concern for health professionals as it decreases therapeutic efficiency while increasing costs, especially in elderly populations. To increase therapeutic adherence in elderly populations, the technology applied in the medical devices that are used must be adapted to improve usability. This paper outlines the rationale behind, and methods applied to assess the usability of, ACHO (Assistant on Care and Health Offline), a voice assistant that provides elderly patients with reminders of medical appointments to attend and when they need to take their medication. This work is a descriptive, cross-sectional, observational study, and will include a three-phase (analysis, testing and refinement) multidimensional usability analysis of an initial prototype, in the setting of a user-driven Living Lab, which enables the needs and characteristics of the end users to be identified and incorporated into the prototype with each iteration, in which a multidisciplinary team of researchers and users will participate as co-creators. This methodology will allow us to develop a better prototype, increasing usability and, thus, increasing therapeutic adherence.

Relationship between exclusive breastfeeding and brain-derived neurotrophic factor in children.

OBJECTIVE: A positive relationship between breastfeeding and brain-derived neurotrophic factor (BDNF) in infants has been suggested due to the presence of BDNF in human milk. This study aimed to determine the relationship between exclusive breastfeeding and BDNF serum levels in Spanish schoolchildren. METHODS: A cross-sectional analysis including 202 schoolchildren, aged eight to 11 years, from Cuenca, Spain, was conducted. Information on sociodemographic and anthropometric variables, sexual maturation, birth weight and exclusive breastfeeding ('no exclusive breastfeeding', and exclusive breastfeeding for ≤6 and >6 months), and BDNF serum levels using an ELISA method were obtained. Covariance analyses (ANCOVA) were conducted to examine the relationship between serological BDNF and exclusive breastfeeding after controlling for potential confounders. RESULTS: ANCOVA models showed no significant differences in BDNF levels between children who were exclusively breastfed for more than six months versus those who were not (p > 0.05). No significant differences were observed by age group (eight to nine years versus 10 to 11 years; p > 0.05). Additionally, no clear negative trend in BDNF serum levels according to sexual maturation categories was found (p > 0.05). CONCLUSION: These findings suggest that exclusive breastfeeding does not have a significant positive association on BDNF from eight to 11 years, since children who were exclusively breastfed did not have significantly higher BDNF levels than those who were not exclusively breastfed. Likewise, BDNF levels were not found to be negatively affected by hormonal development. Future research should examine the influence of exclusive breastfeeding on BDNF over the different developmental stages.

An integrated mathematical model of the cardiovascular and respiratory response to exercise: model-building and comparison with reported models.

The use of physiological models in medicine allows the evaluation of new hypotheses, development of diagnosis and clinical treatment applications, and development of training and medical education tools, as well as medical device design. Although several mathematical models of physiological systems have been presented in the literature, few of them are able to predict the human cardiorespiratory response under physical exercise stimulus adequately. This paper aims to present the building and comparison of an integrated cardiorespiratory model focused on the prediction of the healthy human response under rest and aerobic exercise. The model comprises cardiovascular circulation, respiratory mechanics, and gas exchange system, as well as cardiovascular and respiratory controllers. Every system is based on previously reported physiological models and incorporates reported mechanisms related to the aerobic exercise dynamics. Experimental data of 30 healthy male volunteers undergoing a cardiopulmonary exercise test and simulated data from two of the most current and complete cardiorespiratory models were used to evaluate the performance of the presented model. Experimental design, processing, and exploratory analysis are described in detail. The simulation results were compared against the experimental data in steady state and in transient regime. The predictions of the proposed model closely mimic the experimental data, showing in overall the lowest prediction error (10.35%), the lowest settling times for cardiovascular and respiratory variables, and in general the fastest and similar responses in transient regime. These results suggest that the proposed model is suitable to predict the cardiorespiratory response of healthy adult humans under rest and aerobic exercise conditions.NEW & NOTEWORTHY This paper presents a new cardiorespiratory model focused on the prediction of the healthy human response under rest and aerobic dynamic exercise conditions. Simulation results of cardiorespiratory variables are compared against experimental data and two of the most current and complete cardiorespiratory models.

How Health Habits Influence the Physiological Response During a Physical Activity in Extreme Temperatures?

BACKGROUND: The purpose of the study was to determine to what degree the health habits of university students influence their physiological response during a 10-min high-intensity exercise. METHODS: We conducted a cross-sectional cohort study with 59 health science students, in which we analyzed their adherence to a Mediterranean and low-fat diet, as well as their activity levels. We correlated these factors with the physiological response (lactic acid and heart rate) and a series of anthropometric parameters in intense physical activity (cardiopulmonary resuscitation (CPR) for 10 min) in three scenarios: extreme cold, extreme heat and a control situation at room temperature. RESULTS: The results of this study demonstrate that in university students, a greater adherence to the Mediterranean diet was associated with a better response to physical exercise, in this case, 10-min CPR, in hostile environments. CONCLUSIONS: Following healthy eating guidelines improves physical performance and delays the appearance of fatigue; both are important aspects for a better performance of CPR.

Paper wasps are darker at high elevation.

High mountains are harsh environments in which colder temperatures and higher levels of UV-B radiation are common. These abiotic conditions strongly affect animals' biology, often constraining their survival and reproduction. As a result, adaptations to live in such habitats are expected to evolve. Body color is thought to be adaptive to the environment that animals experience. Tegument melanization improves heat gain and provides photoprotection. Therefore, at high elevation, ectotherms are expected to be darker (well-melanized). We test this prediction in the paper wasp Agelaia pallipes (Hymenoptera: Vespidae), a species distributed across an elevational gradient in the Colombian Andes. We used Malaise traps and sampled a total of 146 wasps along nine elevations, ranging from 2,600-3,380 m above sea level. Standard digital photography was used to measure the body luminance and colour patterning in different body parts of dry-preserved specimens. There was striking variation in body luminance (darker and lighter), color patterning (patched, smoothed, homogeneous) and surface texture (shiny and matte), but the kind and degree of variation depended on the body part examined. Wasps from higher elevations had darker thoraces, confirming our prediction. Besides, at high elevation, the frequency of wasps with a matte rather than a shiny face strongly increased. Overall, our findings support the thermal melanism hypothesis and suggest that intraspecific color variation might be an adaptation to the environment of paper wasps.

Morphological variation of the widely distributed genus Stenocorse Marsh, 1968 (Hymenoptera: Braconidae: Doryctinae).

Stenocorse is a monotypic genus with wide distribution and a large range of beetle hosts. We analyzed the morphological variation of 346 specimens from the USA south to Brasil. We studied 15 morphometric and 30 discrete characters using principal component (PCA) and discriminant function analyses (DFA) to assess character informativeness and the influence of geographic distribution and host source to detect differentiation. Mexican samples were studied according to location and biogeographic provinces. Specimens from Colombia were studied according to the plant where the host was recorded. Three measurements show group differentiation whereas four were redundant. Three groups of individuals were supported by continuous and discrete characters: one found in the USA, Mexico, Nicaragua and Costa Rica, a second from Mexico, and a third from Colombia and Brazil. These groups showed poor agreement with the differentiation of its common beetle host populations. This could be a consequence of the large number of sympatric host species feeding on a large number of plant species. This research shed light on other sources of evidence for building a sound taxonomy for Stenocorse.

Successful Treatment of a Drug-Resistant Epilepsy by Long-term Transcranial Direct Current Stimulation: A Case Report.

Transcranial direct current stimulation (tDCS) is a reemerged noninvasive cerebral therapy used to treat patients with epilepsy, including focal cortical dysplasia, with controversial results. We present a case of a 28-year-old female with left frontal cortical dysplasia refractory to antiepileptic drugs, characterized by 10-15 daily right tonic hemi-body seizures. The patient received a total of seven sessions of cathodal tDCS (2 mA, 30 min). The first three sessions were applied over three consecutive days, and the remaining four sessions of tDCS were given each at 2-week intervals. At the 1-year follow-up, the patient reported to have a single seizure per month and only mild adverse events.

Transcranial Alternating Current Stimulation: A Potential Risk for Genetic Generalized Epilepsy Patients (Study Case).

Transcranial alternating current stimulation (tACS) is a re-emergent neuromodulation technique that consists in the external application of oscillating electrical currents that induces changes in cortical excitability. We present the case of a 16-year-old female with pharmaco-resistant juvenile myoclonic epilepsy to 3 antiepileptic's drugs characterized by 4 myoclonic and 20 absence seizures monthly. She received tACS at 1 mA at 3 Hz pulse train during 60 min over Fp1-Fp2 (10-20 EEG international system position) during 4 consecutive days using an Endeavor™ IOM Systems device® (Natus Medical Incorporated, Middleton, WI, USA). At the 1-month follow-up, she reported a 75% increase in seizures frequency (only myoclonic and tonic-clonic events) and developed a 24-h myoclonic status epilepticus that resolved with oral clonazepam and intravenous valproate. At the 2-month follow-up, the patient reported a 15-day seizure-free period.

Prevalencia de infección por VIH en Bogotá, D.C., Colombia, en 2012. Caracterización por localidades / HIV prevalence in Bogotá, Colombia in 2012. A characterization of localities

Resumen Introducción. La prevalencia de infección por VIH es tema de constante análisis en el sistema de salud y se toma como referente para las políticas de salud pública. Conociendo las diferentes dinámicas poblacionales de esta infección se generan nuevos enfoques para intervenir de manera adecuada en su manejo. Objetivo. Realizar un análisis de prevalencia de la infección por VIH en las localidades de Bogotá, D.C. en el año 2012. Materiales y métodos. Estudio observacional, descriptivo, retrospectivo y de fuente secundaria realizado a partir de los diagnósticos positivos de VIH, proporcionados en una base de datos por la Secretaria Distrital de Salud, y las proyecciones poblacionales suministradas por la Secretaria Distrital de Planeación para el 2012. Resultados. Con una población proyectada de 7 571 345 habitantes en Bogotá D.C., se estimó una tasa global de prevalencia de 19 por 100 000 habitantes, la razón hombre:mujer fue de 6H:1M y el grupo de edad más afectado por la infección fue el de 20 a 34 años. Conclusión. De las 20 localidades de Bogotá, D.C., 8 superan el promedio encontrado para la ciudad, por lo que se constituyen en localidades prioritarias de intervención.

Abstract Introduction: The prevalence of HIV infection is the subject of constant analysis in the health system and is taken as a reference for public health policies. By knowing the different population dynamics of this infection, new approaches to proper management interventions are generated. Objective: To analyze the prevalence of HIV infection in the localities of Bogotá D.C. during 2012. Materials and methods: Observational, descriptive, retrospective and secondary source study conducted based on positive HIV diagnoses obtained from a database of the District Department of Health, and population projections provided by the District Department of Planning for 2012. Results: With a projected population of 7 571 345 inhabitants in Bogotá D.C., an overall prevalence rate of 19 per 100 000 inhabitants was estimated; the ratio man:woman was 6M:1W, and the age group most affected by the infection was 20 to 34 years. Conclusion: Of the 20 localities of Bogotá D.C., 8 are above the average for the city, therefore, they are a priority for intervention.