Striatal medium‐sized spiny neurons express mRNA and protein of GPR55 receptors that stimulate neurotransmitter release; thus, GPR55 could be sent to nigral striatal projections, where it might ...modulate GABA release and motor behavior. Here, we study the presence of GPR55 receptors at striato‐nigral terminals, their modulation of GABA release, their signaling pathway, and their effect on motor activity. By double immunohistochemistry, we found the colocation of GPR55 protein and substance P in the dorsal striatum. In slices of the rat substantia nigra, the GPR55 agonists LPI and O‐1602 stimulated 3H‐GABA release induced by high K+ depolarization in a dose‐dependent manner. The antagonists CID16020046 and cannabidiol prevented agonist stimulation in a dose‐dependent way. The effect of GPR55 on nigral 3H‐GABA release was prevented by lesion of the striatum with kainic acid, which was accompanied by a decrement of GPR55 protein in nigral synaptosomes, indicating the presynaptic location of receptors. The depletion of internal Ca2+ stores with thapsigargin did not prevent the effect of LPI on 3H‐GABA release, but the remotion or chelation of external calcium did. Blockade of Gi, Gs, PLC, PKC, or dopamine D1 receptor signaling proteins did not prevent the effect of GPR55 on release. However, the activation of GPR55 stimulated 3H‐cAMP accumulation and PKA activity. Intranigral unilateral injection of LPI induces contralateral turning. This turning was prevented by CID16020046, cannabidiol, and bicuculline but not by SCH 23390. Our data indicate that presynaptic GPR55 receptors stimulate 3H‐GABA release at striato‐nigral terminals through 3H‐cAMP production and stimulate motor behavior.
Graphical
Nigral presynaptic GPR55 receptors stimulate 3HGABA release by stimulating cAMP production and PKA activity. Nigral GPR55 promotes motor behavior.
Oak species (Fagaceae: Quercus) differ in their distribution at the landscape scale, specializing to a certain portion of environmental gradients. This suggests that functional differentiation favors ...habitat partitioning among closely related species. To elucidate the mechanisms of species coexistence in oak forests, we explored patterns of interspecific variation in functional traits involved in water-use strategies. We tested the hypothesis that oak species segregate along key trade-offs between xylem hydraulic efficiency and safety, and between hydraulic safety and drought avoidance capacity, leading to species niche partitioning across a gradient of aridity. To do so, we quantified biophysical and physiological traits in four red and five white oak species (sections Lobatae and Quercus, respectively) across an aridity gradient in central Mexico. We also explored the trade-offs guiding species differentiation, particularly between the drought tolerance versus water acquisition capacity, and determined whether the water-use strategy was associated with the portion of the environmental gradient that the species occupy. In a trait-by-trait analysis, we detected differences between white and red oak species. However, a larger part of the variation was explained at the species rather than at the section level. We detected two primary axes of trait covariation. The first exhibited differences between species with dense tissues and species with soft tissues (the tissue construction cost axis); however, the oak sections did not constitute separate groups, while the second suggested a trade-off between xylem resistance to cavitation and tree deciduousness. As expected, the water-use strategies of the species were related to the environment; oak species from arid areas had more deciduousness and a higher instantaneous water-use efficiency. In contrast, their humid counterparts had less deciduousness and had a xylem that was more resistant to embolisms. Altogether, these results suggest that aridity filters closely related species, resulting in habitat partitioning and niche divergence.
Information and communication technologies have proven to be an effective way of helping older adults improve independence outcomes, but such technologies are yet not widely used by this segment of ...the population. This paper aims to study computer use and senior citizens’ attitudes toward computer technology in the context of a 20-hour course in basic skills. A questionnaire was used to conduct pre- and postcourse analyses with a sample of 191 adults over the age of 60. The findings show that direct contact with computers generates more positive attitudes toward computer use and also positive relationships with attitudes, user behavior, training expectations, and self-confidence. Results are discussed in the light of need-to-know attitudes toward computer use and training in new technologies as an opportunity for life-long learning and for improving quality of life in old age.
•The chemistries of two new geothermal prospects in the Mexican Volcanic Belt were studied.•La Escalera and Agua Caliente – Tzitzio geothermal areas have hot springs with discharge temperatures of ∼ ...50 °C.•The pH values of hot springs ranging from 6.2 to 8.5.•Main geological structures are La Escalera Caldera, Tzitzio Anticline and the crossing of NE-SW and E-W normal faults.•The hot springs are caused by the interaction among the main geological structures.
The La Escalera and Agua-Caliente Tzitzio geothermal areas are newly discovered geothermal prospects in Mexico that may have the potential to be utilized using binary cycle plants. Hot springs (40–50 °C) are constrained to the river banks in both areas, but gas discharges occur on the banks as well as in the riverbeds. The thermal water is predominantly bicarbonate type. Reconnaissance work yielded encouraging results, as the Na/K geothermometer indicates temperatures between 139 and 245 °C for La Escalera water samples in a partial equilibrium. La Escalera and Tzitzio have strong surface gas discharges, and dry gas samples were collected for δ13C isotopic analysis of CH4 and CO2; the results indicate a magmatic origin for the gas discharged.
Coronavirus disease 2019 (COVID-19) is a highly variable condition. Validated tools to assist in the early detection of patients at high risk of mortality can help guide medical decisions.
We sought ...to validate externally, as well as in patients from the second pandemic wave in Europe, our previously developed mortality prediction model for hospitalized COVID-19 patients.
Three validation cohorts were generated: 2 external with 185 and 730 patients from the first wave and 1 internal with 119 patients from the second wave. The probability of death was calculated for all subjects using our prediction model, which includes peripheral blood oxygen saturation/fraction of inspired oxygen ratio, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, IL-6, and age. Discrimination and calibration were evaluated in the validation cohorts. The prediction model was updated by reestimating individual risk factor effects in the overall cohort (N = 1477).
The mortality prediction model showed good performance in the external validation cohorts 1 and 2, and in the second wave validation cohort 3 (area under the receiver-operating characteristic curve, 0.94, 0.86, and 0.86, respectively), with excellent calibration (calibration slope, 0.86, 0.94, and 0.79; intercept, 0.05, 0.03, and 0.10, respectively). The updated model accurately predicted mortality in the overall cohort (area under the receiver-operating characteristic curve, 0.91), which included patients from both the first and second COVID-19 waves. The updated model was also useful to predict fatal outcome in patients without respiratory distress at the time of evaluation.
This is the first COVID-19 mortality prediction model validated in patients from the first and second pandemic waves. The COR+12 online calculator is freely available to facilitate its implementation (https://utrero-rico.shinyapps.io/COR12_Score/).
Background
Ample evidence indicates a sex‐related difference in severity of COVID‐19, with less favorable outcomes observed in men. Genetic factors have been proposed as candidates to explain this ...difference. The polyglutamine (polyQ) polymorphism in the androgen receptor gene has been recently described as a genetic biomarker of COVID‐19 severity.
Objective
To test the association between the androgen receptor polyQ polymorphism and COVID‐19 severity in a large cohort of COVID‐19 male patients.
Materials and methods
This study included 1136 male patients infected with SARS‐CoV‐2 as confirmed by positive PCR. Patients were retrospectively and prospectively enrolled from March to November 2020. Patients were classified according to their severity into three categories: oligosymptomatic, hospitalized and severe patients requiring ventilatory support. The number of CAG repeats (polyQ polymorphism) at the androgen receptor was obtained by PCR and patients were classified as either short (<23 repeats) or long (≥23 repeats) allele carriers. The association between polyQ alleles (short or long) and COVID‐19 severity was assessed by Chi‐squared (Chi2) and logistic regression analysis.
Results
The mean number of polyQ CAG repeats was 22 (±3). Patients were classified as oligosymptomatic (15.5%), hospitalized (63.2%), and severe patients (21.3%) requiring substantial respiratory support. PolyQ alleles distribution did not show significant differences between severity classes in our cohort (Chi2 test p > 0.05). Similar results were observed after adjusting by known risk factors such as age, comorbidities, and ethnicity (multivariate logistic regression analysis).
Discussion
Androgen sensitivity may be a critical factor in COVID‐19 disease severity. However, we did not find an association between the polyQ polymorphism and the COVID‐19 severity. Additional studies are needed to clarify the mechanism underlying the association between androgens and COVID‐19 outcome.
Conclusions
The results obtained in our study do not support the role of this polymorphism as biomarker of COVID‐19 severity.
•Pasture reform reduced CO2 emissions to the atmosphere by 44.3%.•Pasture reform favored an increase in the stable compartment of organic matter.•CO2 emissions are related to the soil’s organic ...matter compartment.
The emission of CO2 from the soil in agricultural areas is the result of the interaction of several factors, including soil and crop management practices and local edaphoclimatic conditions. The dynamics of organic carbon (OC), in the midst of reform processes in agricultural areas, can be used as an indicator of chemical soil quality because carbon loss is directly related to its lability, quality, or decomposition capacity. This study aimed to evaluate the impact of the reform of degraded pastures in the soil organic matter compartment and its effect on mitigating CO2 emissions. The study was carried out in the municipality of Selvíria, Mato Grosso do Sul, Brazil, in two areas destined for extensive beef cattle grazing, subsidized by the forage plant Urochloa brizantha cv. Marandu. Geostatistical meshes were installed in the areas, and soil samples of deformed and undeformed structures were taken to evaluate the physical and chemical attributes of the soil. The results indicated that soil management practices, followed by the cultivation of sorghum intercropped with U. brizantha, increased the total OC (TOC) stocks through the stable fraction (OC associated with the mineral fraction) and consequent reduction in CO2 emissions from the soil. This highlights the spatial variability in CO2 emissions and how soil attributes affect the flow of CO2 into the atmosphere. The use of multivariate geostatistics has made it possible to forecast CO2 emissions from the soil. This small-scale study provides a theoretical basis for the large-scale spatial monitoring of biogeochemical processes that control CO2 emissions in agricultural ecosystems, particularly in degraded pasture areas.
Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints and presence of systemic autoantibodies, with a great clinical and molecular heterogeneity. ...Rheumatoid Factor (RF) and anti-citrullinated protein antibodies (ACPA) are routinely used for the diagnosis of RA. However, additional serological markers are needed to improve the clinical management of this disease, allowing for better patient stratification and the desirable application of precision medicine strategies. In the present study, we investigated those systemic molecular changes that are associated with the RF and ACPA status of RA patients. To achieve this objective, we followed a proteomic biomarker pipeline from the discovery phase to validation. First, we performed an iTRAQ-based quantitative proteomic experiment on serum samples from the RA cohort of the Hospital of Santiago de Compostela (CHUS). In this discovery phase, serum samples from the CHUS cohort were pooled according to their RF/ACPA status. Shotgun analysis revealed that, in comparison with the double negative group (RF–/ACPA–), the abundance of 12 proteins was altered in the RF+/ACPA+ pool, 16 in the RF+/ACPA– pool and 10 in the RF-/ACPA+ pool. Vitamin D binding protein and haptoglobin were the unique proteins increased in all the comparisons. For the verification phase, 80 samples from the same cohort were analyzed individually. To this end, we developed a Multiple Reaction Monitoring (MRM) method that was employed in a comprehensive targeted analysis with the aim of verifying the results obtained in the discovery phase. Thirty-one peptides belonging to 12 proteins associated with RF and/or ACPA status were quantified by MRM. In a final validation phase, the serum levels of alpha-1-acid glycoprotein 1 (A1AG1), haptoglobin (HPT) and retinol-binding protein 4 (RET4) were measured by immunoassays in the RA cohort of the Hospital of A Coruña (HUAC). The increase of two of these putative biomarkers in the double seropositive group was validated in 260 patients from this cohort (
p
= 0.009 A1AG1;
p
= 0.003 HPT). The increased level of A1AG1 showed association with RF rather than ACPA (
p
= 0.023), whereas HPT showed association with ACPA rather than RF (
p
= 0.013). Altogether, this study has allowed a further classification of the RA seropositive patients into two novel clusters: RF+A1AG+ and ACPA+HPT+. The determination of A1AG1 and HPT in serum would provide novel information useful for RA patient stratification, which could facilitate the effective implementation of personalized medicine in routine clinical practice.
En esta investigación se presenta el análisis y comparación de los resultados reportados en la literatura de 1987 al 2023 relacionados con la capacidad de absorción de energía específica de columnas ...tubulares de materiales compuestos, los cuales se clasificaron en tres categorías: a) laminados con fibras en orientación de 0,90, b) laminados con fibras unidireccionales, y 3) laminados con laminados multidireccionales. Se examinó la absorción de energía específica (SEA) y se realizaron comparaciones entre los estudios. Los resultados exhibieron una amplia dispersión en los datos, incluso para configuraciones aparentemente similares. Las diferencias se atribuyen a factores como dimensiones de probetas, materiales utilizados y técnicas de ensayo. Además, se observó la falta de normativas estandarizadas, lo que dificulta la comparación y la identificación de patrones consistentes. Se concluye que la implementación de estándares unificados mejoraría la coherencia y comparabilidad de los resultados, proporcionando una comprensión más profunda de estos materiales en aplicaciones futuras.
Learning and using new technologies by the older people is seen as a demand for their integration in society and as a factor related to active aging. The goal of this article is to understand the ...attitudes of the elderly towards information and communication technologies in the context of a training course about the utilization of a digital platform. It is the result of an empirical study with a sample of 240 older people registered in the course Tele-Services for the Elderly, that took place in the Centers for the Elderly in the province of Cuenca, Spain. Through a self-administered questionnaire, aspects related to social activity, knowledge and use of the computer and Internet, expectations on learning and use of computer technology, personal competence, and self-concept were evaluated. The results obtained showed relationships between implication in the activities, experience with computers, and belief in the usefulness of learning new technologies. The participants' involvement in the activities was related to greater contact with information and communication technologies (ICT), which, in turn, generated more positive attitudes toward its learning and utility as well as more self-confidence. The elderly said that they enrolled in different activities to learn and to keep their minds active, and they thought of training as a means of social participation and lifelong learning.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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