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The presence of microplastics in freshwater systems can have harmful effects on the food chain. Zooplankton, especially suspension and filter feeders, can ingest microplastics, which can cause adverse effects and transfer them to higher trophic levels. Here, we analyze the presence, abundance, and distribution of microplastics in surface water, zooplankton, and fish in two tropical lakes in central Mexico. We collected water samples in triplicate at three sites in each lake and 120 fish of the genus Chirostoma. From each water sample, 300 rotifers and 150 microcrustaceans were randomly isolated and processed independently. Of the particles found in the water, zooplankton, and fish from both lakes, the fragments were the predominant ones. The total abundance of microplastics in the water column of both lakes varied between 1.2 and 17.0 items L-1. In zooplankton, fragments were found predominantly with up to 0.1 items ind-1, while in fish, up to 4.5 items ind-1 was recorded. Our results confirm the presence of microplastics in different compartments of the food webs of freshwater bodies, water column, zooplankton, and fish. Further work is required on the possible effects of these stressors at the different trophic levels.
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Monitoramento Ambiental , Peixes , Lagos , Microplásticos , Poluentes Químicos da Água , Zooplâncton , Animais , Lagos/química , México , Poluentes Químicos da Água/análise , Microplásticos/análise , Cadeia AlimentarRESUMO
S-nitrosylation of Cx43 gap junction channels critically regulates communication between smooth muscle cells and endothelial cells. This posttranslational modification also induces the opening of undocked Cx43 hemichannels. However, its specific impact on vasomotor regulation remains unclear. Considering the role of endothelial TRPV4 channel activation in promoting vasodilation through nitric oxide (NO) production, we investigated the direct modulation of endothelial Cx43 hemichannels by TRPV4 channel activation. Using the proximity ligation assay, we identify that Cx43 and TRPV4 are found in close proximity in the endothelium of resistance arteries. In primary endothelial cell cultures from resistance arteries (ECs), GSK-induced TRPV4 activation enhances eNOS activity, increases NO production, and opens Cx43 hemichannels via direct S-nitrosylation. Notably, the elevated intracellular Ca2+ levels caused by TRPV4 activation were reduced by blocking Cx43 hemichannels. In ex vivo mesenteric arteries, inhibiting Cx43 hemichannels reduced endothelial hyperpolarization without affecting NO production in ECs, underscoring a critical role of TRPV4/Cx43 signaling in endothelial electrical behavior. We perturbed the proximity of Cx43/TRPV4 by disrupting lipid rafts in ECs using ß-cyclodextrin. Under these conditions, hemichannel activity, Ca2+ influx, and endothelial hyperpolarization were blunted upon GSK stimulation. Intravital microscopy of mesenteric arterioles in vivo further demonstrated that inhibiting Cx43 hemichannels activity, NO production and disrupting endothelial integrity reduce TRPV4-induced relaxation. These findings underscore a new pivotal role of Cx43 hemichannel associated with TRPV4 signaling pathway in modulating endothelial electrical behavior and vasomotor tone regulation.
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Connexin hemichannels were identified as the first members of the eukaryotic large-pore channel family that mediate permeation of both atomic ions and small molecules between the intracellular and extracellular environments. The conventional view is that their pore is a large passive conduit through which both ions and molecules diffuse in a similar manner. In stark contrast to this notion, we demonstrate that the permeation of ions and of molecules in connexin hemichannels can be uncoupled and differentially regulated. We find that human connexin mutations that produce pathologies and were previously thought to be loss-of-function mutations due to the lack of ionic currents are still capable of mediating the passive transport of molecules with kinetics close to those of wild-type channels. This molecular transport displays saturability in the micromolar range, selectivity, and competitive inhibition, properties that are tuned by specific interactions between the permeating molecules and the N-terminal domain that lies within the pore-a general feature of large-pore channels. We propose that connexin hemichannels and, likely, other large-pore channels, are hybrid channel/transporter-like proteins that might switch between these two modes to promote selective ion conduction or autocrine/paracrine molecular signaling in health and disease processes.
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Conexinas , Humanos , Conexinas/metabolismo , Conexinas/genética , Transporte de Íons , Animais , Mutação , Íons/metabolismo , Junções Comunicantes/metabolismo , Canais Iônicos/metabolismo , Canais Iônicos/genéticaRESUMO
Introducción: La esclerosis lateral amiotrófica (ELA) es la forma más común de enfermedad degenerativa de motoneurona en la edad adulta y es considerada una enfermedad terminal. Por lo mismo, el accionar del fonoaudiólogo debe considerar el respeto a los principios bioéticos básicos para garantizar una asistencia adecuada. Objetivo: Conocer aquellas consideraciones bioéticas relacionadas al manejo y estudio de personas con ELA para luego brindar una aproximación hacia el quehacer fonoaudiológico. Método: Se efectuó una búsqueda bibliográfica en las bases de datos PubMed, Scopus y SciELO. Se filtraron artículos publicados desde 2000 hasta junio de 2023 y fueron seleccionados aquellos que abordaban algún componente bioético en población con ELA. Resultados: Aspectos relacionados al uso del consentimiento informado y a la toma de decisiones compartidas destacaron como elementos esenciales para apoyar la autonomía de las personas. Conclusión: Una correcta comunicación y una toma de decisiones compartida son claves para respetar la autonomía de las personas. A su vez, la estandarización de procedimientos mediante la investigación clínica permitirá aportar al cumplimiento de los principios bioéticos de beneficencia y no maleficencia, indispensables para la práctica profesional.
Introduction: Amyotrophic lateral sclerosis (ALS) is the most common form of degenerative motor neuron disease in adulthood and is considered a terminal disease. For this reason, the actions of the speech therapist must consider respect for basic bioethical principles to guarantee adequate assistance. Objective: To know those bioethical considerations related to the management and study of people with ALS to then provide an approach to speech therapy. Methodology: A bibliographic search was carried out in the PubMed, Scopus, and SciELO databases. Articles published from 2000 to June 2023 were filtered and those that addressed a bioethical component in the population with ALS were selected. Results: Aspects related to the use of informed consent and shared decision-making stood out as essential elements to support people's autonomy. Conclusion: Proper communication and shared decision-making are key to respecting people's autonomy. In turn, the standardization of procedures through clinical research will contribute to compliance with the bioethical principles of beneficence and non-maleficence, essential for professional practice.
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SUMMARY: Although almost all studies exclude lip conditions because they would affect furrow patterns, some authors maintain that they should be considered temporary or permanent disabilities, all of which require further research in this context.We present a study in which we associate lip conditions with lip print patterns to associate both morphological elements for fieldwork purposes. Fifty-seven women and 48 men aged between 19 and 38 years who resided in Temuco (Chile) were included. The lip conditions and their prints were recorded, and an analysis, comparison, evaluation, and verification protocol (ACE-V) for lip prints was applied. Of the participants, 27.4 % had healthy lips, while 71.7 % had some type of condition. Although patterns related to temporary and permanent lip conditions were recognized in the lip prints in a non-significant way, the diagnosis of "healthy" or "altered" lip status could be made significantly by a calibrated examiner. Although these conditions do not represent identifying variables without empirical studies to validate them, they can affect the quality of the evaluated lip print; therefore, they should be recognized during the analyses considering the prevalence of these conditions.
Aunque casi todos los estudios excluyen las afecciones labiales pues afectarían los patrones de sus surcos y huellas, algunos autores sostienen que deben ser consideradas alteraciones temporales o permanentes, por lo que se requiere mayor investigación en este aspecto. Se presenta un estudio en el que se asocian afecciones labiales con sus patrones de huellas para evaluar conjuntamente ambos elementos morfológicos con fines de trabajo forense de campo. Se incluyeron 57 mujeres y 48 hombres con edades entre 19 y 38 años residentes en Temuco (Chile). Se registraron las afecciones de los labios y sus huellas, y se aplicó un protocolo de análisis, comparación, evaluación y verificación (ACE-V) para las huellas labiales. De los participantes, el 27,4 % tenía labios sanos, mientras que el 71,7 % presentaba algún tipo de afección. Aunque los patrones relacionados con afecciones labiales temporales y permanentes se reconocieron en las huellas labiales de manera no significativa, un examinador calibrado podría realizar significativamente el diagnóstico de estado labial "sano" o "alterado". Si bien estas condiciones no representan variables de identificación sin estudios empíricos que las validen, pueden afectar la calidad de la impresión labial evaluada; por lo tanto, deben ser reconocidos durante los análisis considerando la prevalencia de estas condiciones.
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Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Antropologia Forense , Identificação Biométrica/métodos , Lábio/anatomia & histologiaRESUMO
PURPOSE: To analyze the effects of exergames on rehabilitation outcomes in osteoarthritis (OA) patients. MATERIALS AND METHODS: A systematic review was reported according to the PRISMA statement. Randomized controlled trials (RCTs) were searched in Pubmed, Scopus, WoS, CINAHL, and PEDro (inception to November 2023). Studies that applied non-immersive exergames and assessed physical, functional, cognitive, pain, and psychosocial outcomes were included. Comparisons were other exercise modalities and non-intervention. Methodological quality was assessed with PEDro scale, and risk of bias (RoB) was assessed with Cochrane RoB-2 tool. RESULTS: Eight studies were included (total of participants = 401). The mean PEDro score was 6.1, and seven studies had high RoB. Seven studies involved knee OA and one cervical OA. The most frequent duration for interventions was four weeks. Exergames were more effective than controls in at least one outcome in all studies. The outcomes for which exergames were most effective were functional disability, postural balance, muscle strength, proprioception, gait, range of motion, pain, quality of life, depression, and kinesiophobia. CONCLUSION: Non-immersive exergames constitute an effective strategy for optimizing several relevant outcomes in rehabilitation. However, more RCTs with high methodological quality are required to deepen the knowledge about the multidimensional effects of exergames in OA patients.
Osteoarthritis (OA) is one of the leading causes of disability, involving high health costs and a public health problem.Physical exercise has recently been recognized as a first-line treatment in OA to reduce symptomatology and to improve or maintain physical functioning and quality of life.Non-immersive exergames are a safe therapeutic strategy to improve functional disability, postural balance, muscle strength, proprioception, gait performance, range of motion, and pain in OA patients.Similarly, non-immersive virtual reality strategies contribute to the improvement of depression, kinesiophobia, and quality of life in people with OA.
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Microplastics (MPs) are found in a wide range of ecosystems, from the Arctic to the deep ocean. However, there is no data on their presence in terrestrial mammals that inhabit the Selva Maya. The aim of this study is to detect the presence of MPs in the feces of the Baird's tapir (Tapirus bairdii) from the region of Calakmul, located in the Yucatan Peninsula, Mexico. We analyzed 129 fecal samples collected during 2017 and 2018, obtaining 57 and 72 samples during the rainy and dry seasons respectively. Sixty-eight percent of the samples contained 743 MPs with a mean of 19.3 ± 28.1 MPs/kg of dry weight (DW) feces in both years. An inter-annual variation in the average abundance of microplastic was observed during the two-year period (2017-2018), with a 72 % increase in these plastic particles in feces. Fourteen polymers were identified, with ethylene vinyl acetate (EVA), polypropylene (PP) and polyester (PES) being the most abundant during both years. Although the effects of MPs on the health of tapirs are not known, their presence is cause for concern. There is an urgent need for the implementation of appropriate plastic waste management programs in communities of the Selva Maya to diminish the consumption of MPs in species including humans where they pose a significant risk to health. ENVIRONMENTAL IMPLICATIONS: The use of plastics worldwide is increasing every day, so the presence of microplastics is and will continue to be a major environmental problem. It is known that contaminants can adhere to plastics, making them hazardous materials. Microplastics can contaminate remote areas such as Biosphere Reserves. Terrestrial species such as the tapir can ingest microplastics, putting their health at risk. Knowing the dispersion of microplastics is very important in order to manage them properly, taking into account their emission sources and type of polymer.
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Monitoramento Ambiental , Fezes , Microplásticos , Perissodáctilos , Animais , Microplásticos/análise , Fezes/química , México , Poluentes Químicos da Água/análise , Plásticos/análise , Estações do AnoRESUMO
This article contrasts the different approaches to COVID-19 vaccine development adopted by Oxford University, on one hand, and Texas Children's Hospital and Baylor College of Medicine (collectively, Texas), on the other hand. Texas was praised widely in the press and academic literature for adopting an "open source" approach to vaccine development. Oxford, however, chose to license its vaccine technology to pharmaceutical manufacturer AstraZeneca and received significant public criticism as a result. Yet the Oxford vaccine reached far more individuals in developing countries than the Texas vaccine. We compare the two vaccines' experiences, drawing attention to a constellation of interrelated elements that contribute to a successful vaccine production program, including not only IP licensing, but also timing, technology transfer, and resource mobilization, all in the context of the prevailing funding environments. This comparative analysis sheds light on how the innovation ecosystem functioned during the COVID-19 pandemic, providing useful insights for policy makers and advocates as they prepare for future pandemics and other global health challenges.
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BACKGROUND: Astrocytes Ca2+ signaling play a central role in the modulation of neuronal function. Activation of metabotropic glutamate receptors (mGluR) by glutamate released during an increase in synaptic activity triggers coordinated Ca2+ signals in astrocytes. Importantly, astrocytes express the Ca2+-dependent nitric oxide (NO)-synthetizing enzymes eNOS and nNOS, which might contribute to the Ca2+ signals by triggering Ca2+ influx or ATP release through the activation of connexin 43 (Cx43) hemichannels, pannexin-1 (Panx-1) channels or Ca2+ homeostasis modulator 1 (CALHM1) channels. Hence, we aim to evaluate the participation of NO in the astrocytic Ca2+ signaling initiated by stimulation of mGluR in primary cultures of astrocytes from rat brain cortex. RESULTS: Astrocytes were stimulated with glutamate or t-ACPD and NO-dependent changes in [Ca2+]i and ATP release were evaluated. In addition, the activity of Cx43 hemichannels, Panx-1 channels and CALHM1 channels was also analyzed. The expression of Cx43, Panx-1 and CALHM1 in astrocytes was confirmed by immunofluorescence analysis and both glutamate and t-ACPD induced NO-mediated activation of CALHM1 channels via direct S-nitrosylation, which was further confirmed by assessing CALHM1-mediated current using the two-electrode voltage clamp technique in Xenopus oocytes. Pharmacological blockade or siRNA-mediated inhibition of CALHM1 expression revealed that the opening of these channels provides a pathway for ATP release and the subsequent purinergic receptor-dependent activation of Cx43 hemichannels and Panx-1 channels, which further contributes to the astrocytic Ca2+ signaling. CONCLUSIONS: Our findings demonstrate that activation of CALHM1 channels through NO-mediated S-nitrosylation in astrocytes in vitro is critical for the generation of glutamate-initiated astrocytic Ca2+ signaling.
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Astrócitos , Sinalização do Cálcio , Óxido Nítrico , Animais , Ratos , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Conexina 43/metabolismo , Ácido Glutâmico/metabolismo , Óxido Nítrico/metabolismo , Ratos WistarRESUMO
Thermosensation, the ability to detect and estimate temperature, is an evolutionarily conserved process that is essential for survival. Thermosensing is impaired in various pain syndromes, resulting in thermal allodynia, the perception of an innocuous temperature as painful, or thermal hyperalgesia, an exacerbated perception of a painful thermal stimulus. Several behavioral assays exist to study thermosensation and thermal pain in rodents, however, most rely on reflexive withdrawal responses or the subjective quantification of spontaneous nocifensive behaviors. Here, we created a new apparatus, the thermal escape box, which can be attached to temperature-controlled plates and used to assess temperature-dependent effort-based decision-making. The apparatus consists of a light chamber with an opening that fits around temperature-controlled plates, and a small entryway into a dark chamber. A mouse must choose to stay in a brightly lit aversive area or traverse the plates to escape to the enclosed dark chamber. We quantified escape latencies of adult C57Bl/6 mice at different plate temperatures from video recordings and found they were significantly longer at 5 °C, 18 °C, and 52 °C, compared to 30 °C, a mouse's preferred ambient temperature. Differences in escape latencies were abolished in male Trpm8-/- mice and in male Trpv1-/- animals. Finally, we show that chronic constriction injury procedures or oxaliplatin treatement significantly increased escape latencies at cold temperatures compared to controls, the later of which was prevented by the analgesic meloxicam. This demonstrates the utility of this assay in detecting cold pain. Collectively, our study has identified a new and effective tool that uses cost-benefit valuations to study thermosensation and thermal pain.
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With the Supreme Court's decision in Dobbs, reproductive research now joins other sensitive research topics that present legal risks to research participants, underscoring the role of Certificates in protecting them. Yet, stakeholders question whether Certificates will hold up in court. In this article, we describe the essential arguments supporting Congress's regulation of biomedical research and, thus, Certificates, under its authority to regulate interstate commerce. Our analysis should reassure researchers and Institutional review boards who rely on Certificates to protect the confidentiality of research participants' data. We conclude with recommendations for stakeholders based on our analysis.
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Toxoplasma gondii, a medically important intracellular parasite, uses GRA proteins secreted from dense granule organelles to mediate nutrient flux across the parasitophorous vacuole membrane (PVM). GRA17 and GRA23 are known pore-forming proteins on the PVM involved in this process, but the roles of additional proteins have remained largely uncharacterized. We recently identified GRA72 as synthetically lethal with GRA17. Deleting GRA72 produced similar phenotypes to Δgra17 parasites, and computational predictions suggested it forms a pore. To understand how GRA72 functions, we performed immunoprecipitation experiments and identified GRA47 as an interactor of GRA72. Deletion of GRA47 resulted in an aberrant "bubble vacuole" morphology with reduced small molecule permeability, mirroring the phenotype observed in GRA17 and GRA72 knockouts. Structural predictions indicated that GRA47 and GRA72 form heptameric and hexameric pores, respectively, with conserved histidine residues lining the pore. Mutational analysis highlighted the critical role of these histidines for protein functionality. Validation through electrophysiology confirmed alterations in membrane conductance, corroborating their pore-forming capabilities. Furthermore, Δgra47 parasites and parasites expressing GRA47 with a histidine mutation had reduced in vitro proliferation and attenuated virulence in mice. Our findings show the important roles of GRA47 and GRA72 in regulating PVM permeability, thereby expanding the repertoire of potential therapeutic targets against Toxoplasma infections. IMPORTANCE: Toxoplasma gondii is a parasite that poses significant health risks to those with impaired immunity. It replicates inside host cells shielded by the PVM, which controls nutrient and waste exchange with the host. GRA72, previously identified as essential in the absence of the GRA17 nutrient channel, is implicated in forming an alternative nutrient channel. Here we found that GRA47 associates with GRA72 and is also important for the PVM's permeability to small molecules. Removal of GRA47 leads to distorted vacuoles and impairs small molecule transport across the PVM, resembling the effects of GRA17 and GRA72 deletions. Structural models suggest GRA47 and GRA72 form distinct pore structures, with a pore-lining histidine critical to their function. Toxoplasma strains lacking GRA47 or those with a histidine mutation have impaired growth and reduced virulence in mice, highlighting these proteins as potential targets for new treatments against toxoplasmosis.
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Toxoplasma , Animais , Camundongos , Histidina/metabolismo , Permeabilidade , Proteínas de Protozoários/genética , Toxoplasma/genética , Vacúolos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismoRESUMO
Individual hematopoietic stem cells (HSCs) produce different amounts of blood cells upon transplantation. Taking advantage of the intercellular variation, we developed an experimental and bioinformatic approach to evaluating the quantitative association between gene expression and blood cell production across individual HSCs. We found that most genes associated with blood production exhibit the association only at some levels of blood production. By mapping gene expression with blood production, we identified four distinct patterns of their quantitative association. Some genes consistently correlate with blood production over a range of levels or across all levels, and these genes are found to regulate lymphoid but not myeloid production. Other genes exhibit one or more clear peaks of association. Genes with overlapping peaks are found to be coexpressed in other tissues and share similar molecular functions and regulatory motifs. By dissecting intercellular variations, our findings revealed four quantitative association patterns that reflect distinct dose-response molecular mechanisms modulating the blood cell production of HSCs.
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Células Sanguíneas , Células-Tronco Hematopoéticas , Camundongos , Animais , Células-Tronco Hematopoéticas/metabolismo , Expressão Gênica , Diferenciação CelularRESUMO
Background Astrocytes Ca2+ signaling play a central role in the modulation of neuronal function. Activation of metabotropic glutamate receptors (mGluR) by glutamate released during an increase in synaptic activity triggers coordinated Ca2+ signals in astrocytes. Importantly, astrocytes express the Ca2+-dependent nitric oxide (NO)-synthe-tizing enzymes eNOS and nNOS, which might contribute to the Ca2+ signals by triggering Ca2+ influx or ATP release through the activation of connexin 43 (Cx43) hemichannels, pannexin-1 (Panx-1) channels or Ca2+ homeostasis modulator 1 (CALHM1) channels. Hence, we aim to evaluate the participation of NO in the astrocytic Ca2+ signaling initiated by stimulation of mGluR in primary cultures of astrocytes from rat brain cortex. Results Astrocytes were stimulated with glutamate or t-ACPD and NO-dependent changes in [Ca2+]i and ATP release were evaluated. In addition, the activity of Cx43 hemichannels, Panx-1 channels and CALHM1 channels was also analyzed. The expression of Cx43, Panx-1 and CALHM1 in astrocytes was confirmed by immunofluorescence analysis and both glutamate and t-ACPD induced NO-mediated activation of CALHM1 channels via direct S-nitrosylation, which was further confirmed by assessing CALHM1-mediated current using the two-electrode voltage clamp technique in Xenopus oocytes. Pharmacological blockade or siRNA-mediated inhibition of CALHM1 expression revealed that the opening of these channels provides a pathway for ATP release and the subsequent purinergic receptordependent activation of Cx43 hemichannels and Panx-1 channels, which further contributes to the astrocytic Ca2+ signaling. Conclusions Our findings demonstrate that activation of CALHM1 channels through NO-mediated S-nitrosylation in astrocytes in vitro is critical for the generation of glutamate-initiated astrocytic Ca2+ signaling.
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Background: Cirrhosis detection in primary care relies on low-performing biomarkers. Consequently, up to 75% of subjects with cirrhosis receive their first diagnosis with decompensation when causal treatments are less effective at preserving liver function. We investigated an unprecedented approach to cirrhosis detection based on dynamic breath testing. Methods: We enrolled 29 subjects with cirrhosis (Child-Pugh A and B), and 29 controls. All subjects fasted overnight. Breath samples were taken using Breath Biopsy® before and at different time points after the administration of 100 mg limonene. Absolute limonene breath levels were measured using gas chromatography-mass spectrometry. Results: All subjects showed a >100-fold limonene spike in breath after administration compared to baseline. Limonene breath kinetics showed first-order decay in >90% of the participants, with higher bioavailability in the cirrhosis group. At the Youden index, baseline limonene levels showed classification performance with an area under the roc curve (AUROC) of 0.83 ± 0.012, sensitivity of 0.66 ± 0.09, and specificity of 0.83 ± 0.07. The best performing timepoint post-administration was 60 min, with an AUROC of 0.91, sensitivity of 0.83 ± 0.07, and specificity of 0.9 ± 0.06. In the cirrhosis group, limonene bioavailability showed a correlation with MELD and fibrosis indicators, and was associated with signs of portal hypertension. Conclusions: Dynamic limonene breath testing enhances diagnostic performance for cirrhosis compared to static testing. The correlation with disease severity suggests potential for monitoring therapeutic interventions. Given the non-invasive nature of breath collection, a dynamic limonene breath test could be implemented in primary care.
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Toxoplasma gondii, a medically important intracellular parasite, uses GRA proteins, secreted from dense granule organelles, to mediate nutrient flux across the parasitophorous vacuole membrane (PVM). GRA17 and GRA23 are known pore-forming proteins on the PVM involved in this process, but the roles of additional proteins have remained largely uncharacterized. We recently identified GRA72 as synthetically lethal with GRA17. Deleting GRA72 produced similar phenotypes to Δgra17 parasites, and computational predictions suggested it forms a pore. To understand how GRA72 functions we performed immunoprecipitation experiments and identified GRA47 as an interactor of GRA72. Deletion of GRA47 resulted in an aberrant 'bubble vacuole' morphology with reduced small molecule permeability, mirroring the phenotype observed in GRA17 and GRA72 knockouts. Structural predictions indicated that GRA47 and GRA72 form heptameric and hexameric pores, respectively, with conserved histidine residues lining the pore. Mutational analysis highlighted the critical role of these histidines for protein functionality. Validation through electrophysiology confirmed alterations in membrane conductance, corroborating their pore-forming capabilities. Furthermore, Δgra47 parasites and parasites expressing GRA47 with a histidine mutation had reduced in vitro proliferation and attenuated virulence in mice. Our findings show the important roles of GRA47 and GRA72 in regulating PVM permeability, thereby expanding the repertoire of potential therapeutic targets against Toxoplasma infections.
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Profile determination in field hockey is critical to determining athletes' physical strengths and weaknesses, and is key in planning, programming, and monitoring training. This study pursued two primary objectives: (i) to provide descriptive data on sprinting, deceleration, and change of direction (COD) abilities and (ii) to elucidate the mechanical variables that influence sprint and COD performance in elite female field hockey players. Using radar and time-gate technology, we assessed performance and mechanical data from 30 m sprinting, deceleration, and COD tests for 26 elite female hockey players. A machine learning approach identified mechanical variables related to sprint and COD performance. Our findings offer a framework for athlete categorization and the design of performance-enhancing training strategies at the international level. Two pivotal mechanical variables-relative maximum horizontal force (F0) and maximum velocity (Vmax)-predominantly influence the times across all tested distances. However, the force-velocity profile (FVP) and horizontal deceleration do not influence the variance in the COD test outcomes. These insights can guide the design, adjustment, and monitoring of training programs, assisting coaches in decision making to optimize performance and mitigate injury risks for female hockey players.
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Hóquei , Humanos , Feminino , Atletas , Aprendizado de Máquina , RadarRESUMO
Introduction: The COVID-19 pandemic resulted in an unpredictable healthcare crisis with a high psychological burden on healthcare workers. Objective: To evaluate burnout levels and their associated demographics and occupational factors among intensive care unit healthcare workers during the COVID-19 pandemic in a single hospital in the city of Temuco, Chile. Methods: A cross-sectional design in which a sociodemographic questionnaire and the Maslach Burnout Inventory for Human Services were sent to health care workers in a single Chilean Intensive Care Unit during the pandemic COVID-19. Burnout levels, demographic, and occupational factors are reported using descriptive statistics; correlations between burnout levels and demographic-occupational factors were analyzed using Spearman's and rank-biserial correlation coefficients; and multiple linear stepwise regression was used to assess the contribution of demographic and occupational factors to participants' burnout levels. Results: A total of 84 participants (46 women and 38 men) were included in the analysis. Depersonalization and low personal accomplishment were evidenced in 95.2% and 98.8% of the intensive care unit healthcare workers, respectively. Emotional exhaustion was positively correlated with having children ( = 0.72; < 0.01). Age ( = 0.79; < 0.05), sex ( = 0.30; < 0.05), and prior experience in intensive care unit facilities ( = 0.71; < 0.05) were correlated with depersonalization. Feeling of personal accomplishment was positively correlated with with sex ( = 0.70; < 0.05) and type of work shift ( = 0.29; < 0.01). Conclusions: The intensive care unit healthcare workers in this study reported high levels of depersonalization and low feelings of personal accomplishment during an advanced stage of the COVID-19 pandemic. Older age, being female, having children, having intensive care unit experience, and working at 4th shift were factors related to burnout dimensions.