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ABSTRACTToxoplasma gondii is an obligate intracellular parasite responsible for a pathology called toxoplasmosis, which primarily affects immunocompromised individuals and developing foetuses. The parasite can scavenge essential nutrients from its host to support its growth and survival. Among them, iron is one of the most important elements needed to sustain basic cellular functions as it is involved in a number of key metabolic processes, including oxygen transport, redox balance, and electron transport. We evaluated the effects of an iron chelator on the development of several parasite strains and found that they differed in their ability to tolerate iron depletion. The growth of parasites usually associated with a model of acute toxoplasmosis was strongly affected by iron depletion, whereas cystogenic strains were less sensitive as they were able to convert into persisting developmental forms that are associated with the chronic form of the disease. Ultrastructural and biochemical characterization of the impact of iron depletion on parasites also highlighted striking changes in both their metabolism and that of the host, with a marked accumulation of lipid droplets and perturbation of lipid homoeostasis. Overall, our study demonstrates that although acute iron depletion has an important effect on the growth of T. gondii, it has a more profound impact on actively dividing parasites, whereas less metabolically active parasite forms may be able to avoid some of the most detrimental consequences.

ABSTRACT Iron-sulfur (Fe-S) clusters are ubiquitous inorganic cofactors required for numerous essential cellular pathways. Since they cannot be scavenged from the environment, Fe-S clusters are synthesized de novo in cellular compartments such as the apicoplast, mitochondrion, and cytosol. The cytosolic Fe-S cluster biosynthesis pathway relies on the transport of an intermediate from the mitochondrial pathway. An ATP-binding cassette (ABC) transporter called ABCB7 is responsible for this role in numerous commonly studied organisms, but its role in the medically important apicomplexan parasites has not yet been studied. Here we identify and characterize a Toxoplasma gondii ABCB7 homolog, which we name ABCB7-like (ABCB7L). Genetic depletion shows that it is essential for parasite growth and that its disruption triggers partial stage conversion. Characterization of the knock-down line highlights a defect in the biogenesis of cytosolic and nuclear Fe-S proteins leading to defects in protein translation and other pathways including DNA and RNA replication and metabolism. Our work provides support for a broad conservation of the connection between mitochondrial and cytosolic pathways in Fe-S cluster biosynthesis and reveals its importance for parasite survival.IMPORTANCEIron-sulfur (Fe-S) clusters are inorganic cofactors of proteins that play key roles in numerous essential biological processes, for example, respiration and DNA replication. Cells possess dedicated biosynthetic pathways to assemble Fe-S clusters, including a pathway in the mitochondrion and cytosol. A single transporter, called ABCB7, connects these two pathways, allowing an essential intermediate generated by the mitochondrial pathway to be used in the cytosolic pathway. Cytosolic and nuclear Fe-S proteins are dependent on the mitochondrial pathway, mediated by ABCB7, in numerous organisms studied to date. Here, we study the role of a homolog of ABCB7, which we name ABCB7-like (ABCB7L), in the ubiquitous unicellular apicomplexan parasite Toxoplasma gondii. We generated a depletion mutant of Toxoplasma ABCB7L and showed its importance for parasite fitness. Using comparative quantitative proteomic analysis and experimental validation of the mutants, we show that ABCB7L is required for cytosolic and nuclear, but not mitochondrial, Fe-S protein biogenesis. Our study supports the conservation of a protein homologous to ABCB7 and which has a similar function in apicomplexan parasites and provides insight into an understudied aspect of parasite metabolism.

El síndrome de Ehlers-Danlos (SEDh) hipermóvil es el subtipo de SED más frecuente, con genética desconocida y un frecuente retraso diagnóstico y terapéutico. Presentamos el caso de una mujer de 33 años con dolor abdominal crónico y refractario, que desde la infancia presentaba hiperlaxitud generalizada, clínica articular recurrente, acrocianosis distal y migrañas. En la exploración destacaba hábito marfanoide, actitud escoliótica, hiperextensión cutánea, hiperlaxitud articular y cicatrices queloides. Se realizó el diagnóstico diferencial de dolor abdominal crónico e hiperlaxitud articular, solicitándose pruebas analíticas, de imagen y genética del SED, resultando todo normal, salvo varices periuterinas-perivaginales. Se sospechó un SEDh con trastorno gastrointestinal funcional secundario. Ante la refractariedad y el deterioro clínico progresivo con pérdida ponderal, se solicitó una angio-RM que demostró un síndrome de la arteria mesentérica superior (AMS). Fue diagnosticada de SEDh y AMS, relación infrecuente pero descrita, decidiéndose manejo multidisciplinar con tratamiento conservador, reservando la cirugía para complicaciones graves.

While most academic research on care work shows that it struggles to be socially and economically recognized, home help organizations for the elderly seem, on the contrary, to be appropriating the notion of care in their practice and communications. This is embodied in the benevolent attitude of at-home caregivers, which corresponds to the expectations of the hierarchy and public regarding their occupational know-how. But instead of contributing to the recognition of the richness of the emotional labour of caregivers, the constraint to show exclusively positive emotions impoverishes their work. The requirement to always be happy demands that caregivers hide their emotions and makes it difficult to set boundaries.

The increasing ubiquity of digital devices in childhood had outpaced the understanding of their effects on cognitive development, creating a significant research gap regarding their long-term impact. Objective: The present narrative overview explored the complex relationship between digital device usage and cognitive development in childhood. Methods: We conducted a comprehensive literature search across multiple databases, including PubMed, Embase, Scopus, and Web of Science, to critically assess cognitive domains such as attention, memory, executive functions, problem-solving skills, and social cognition. Incorporating over 157 peer-reviewed studies published between 2001 and 2024, we used strict inclusion and exclusion criteria to ensure scientific rigor. Results: The review integrated empirical findings with established theoretical frameworks, particularly from cognitive development and media psychology, to highlight both the advantages and risks of early, frequent exposure to technology. The potential for digital devices to enhance cognitive skills, such as multitasking and information processing, was weighed against risks such as cognitive overload, diminished attention spans, and impaired social skills. We also examined psychological and behavioral outcomes, including identity formation, emotional regulation, and maladaptive behaviors associated with excessive screen time. Additionally, we identified strategies to mitigate negative effects, emphasizing structured digital engagement and parental involvement to support healthy cognitive and psychological growth. Our findings provided actionable recommendations for parents, educators, and policymakers, promoting optimal digital practices that enhanced cognitive development while safeguarding against potential harms. Conclusions: The review offered essential insights for stakeholders in child development, education, and policy-making, highlighting the need for balanced integration of digital tools in childhood learning environments.

Recent evidence from chronobiology, chssronomedicine and chronopsychology shows that the organisation of social time (e.g., school schedules) generally does not respect biological time. This raises concerns about the impact of the constant mismatch between students’ social and internal body clocks on their health, well-being and academic performance. The present paper describes a protocol used to investigate the problem of (de) synchronisation of biological times (chronotypes) in childhood and youth in relation to school times. It studies the effects of student chronotype vs. school schedule matches/mismatches on health behaviours (e.g., how many hours students sleep, when they sleep, eat, do physical activity, spend time outdoors in daylight) and learning (verbal expression, spatial structuring, operations) and whether alert-fatigue levels mediate this effect alignments/misalignments on learning (verbal expression, spatial structuring, operations) and their mediation by alert-fatigue levels. The novelty of our protocol lies in its multidisciplinary and mixed methodology approach to a relevant and complex issue. It draws on up-to-date knowledge from the areas of biology, medicine, psychology, pedagogy and sociology. The methods employed include a varied repertoire of techniques from hormonal analysis (cortisol and melatonin), continuous activity and light monitoring, self-registration of food intake, sleep timings, exercise and exposure to screens, alongside with systematic application of cognitive performance tests (e.g., memory, reasoning, calculation, attention) and self-reported well-being. This comprehensive and interdisciplinary protocol should support evidence-based education policy measures related to school time organisation. Appropriate and healthier school timetables will contribute to social change, healthier students and with more efficient learning. The results of studies using a similar methodology in other countries would ensure replication and comparability of results and contribute to knowledge to support policy making.

RESUMEN En Argentina, nitrógeno (N) y fósforo (P) y recientemente azufre (S) y cinc (Zn) son nutrientes reconocidos como limitantes de la producción de los cereales de invierno. Las decisiones de manejo de la fertilización en avena (Avena sativa L.), cebada (Hordeun vulgare L.) y trigo (Triticum aestivum L.) se realiza considerando aportes individuales de nutriente desconociendo la contribución combinada de elementos. La aplicación combinada de nutrientes mejoraría la respuesta a la fertilización comparada con el aporte individual de los elementos requiriendo su inclusión en los planteos o estrategias de manejo de la fertilización de cereales de invierno. El objetivo fue cuantificar los aportes a la producción de granos de avena, de cebada y de trigo de aplicar P, N, S, y Zn en forma individual y su relación con el uso combinado como NP y NPSZn. En 3 sitios (Tandil, San Manuel y Lobería, Argentina) y en tres cultivos (Trigo, Cebada y Avena) se realizaron experimentos de fertilización considerando aportes individuales y combinados de P, N, S y Zn. La fertilización combinada incorporando P, N, S y Zn presentó rendimientos mayores respec-to a los efectos individuales de estos nutrientes en trigo y en cebada. Los incrementos de rendimientos atribuidos a la diferencia entre la fertilización combinada sobre la suma de los efectos de fertilización individual fueron de 330 kg ha-1 en trigo y de 352 kg ha-1 en cebada. En avena, los datos disponibles no permiten determinar diferencias entre la fertilización combinada y los aportes individuales de cada nutriente. Para las condiciones evaluadas tanto en trigo como en cebada, en la decisión de fertilización con P-N-S-Zn, las fertilizaciones combinadas capturan respuestas de rendimientos adicionales a lo logrado en las respuestas a los nutrientes individuales.

Background/Objectives: The purpose of this study was to investigate whether or not there are notable differences between male and female vocational training students in terms of academic, behavioral, and psychophysiological characteristics. Methods: A total of 411 vocational training students, 210 of whom were male and 201 of whom were female, participated in an online survey that assessed academic, behavioral, and psychophysiological patterns. Results: In terms of extraversion and openness to experience, our research revealed that no statistically significant differences were noticed. When it came to agreeableness, however, significant differences were seen, with female students getting higher marks than male students. Furthermore, we found that there were significant gender differences in terms of neuroticism and conscientiousness, with female students achieving higher scores than male students. When compared to their male counterparts, females displayed higher performance in terms of academic success. They also demonstrated superior values in terms of reported stress, anxiety, and cognitive inflexibility. Conclusions: The findings of this study provide a more in-depth understanding of the numerous factors that have an impact on students engaging in vocational training. This will serve as a foundation for the development of individualized instructional and support programs.

Pathogenic protists are a group of organisms responsible for causing a variety of human diseases including malaria, sleeping sickness, Chagas disease, leishmaniasis, and toxoplasmosis, among others. These diseases, which affect more than one billion people globally, mainly the poorest populations, are characterized by severe chronic stages and the lack of effective antiparasitic treatment. Parasitic protists display complex life-cycles and go through different cellular transformations in order to adapt to the different hosts they live in. Autophagy, a highly conserved cellular degradation process, has emerged as a key mechanism required for these differentiation processes, as well as other functions that are crucial to parasite fitness. In contrast to yeasts and mammals, protist autophagy is characterized by a modest number of conserved autophagy-related proteins (ATGs) that, even though, can drive the autophagosome formation and degradation. In addition, during their intracellular cycle, the interaction of these pathogens with the host autophagy system plays a crucial role resulting in a beneficial or harmful effect that is important for the outcome of the infection. In this review, we summarize the current state of knowledge on autophagy and other related mechanisms in pathogenic protists and their hosts. We sought to emphasize when, how, and why this process takes place, and the effects it may have on the parasitic cycle. A better understanding of the significance of autophagy for the protist life-cycle will potentially be helpful to design novel anti-parasitic strategies. Abbreviations: AAs: amino acids; ATGs: autophagy-related proteins; ADCD; autophagy-dependent cell death; AMPK: 5’ adenosine monophosphate-activated protein kinase; CD40: Cluster of differentiation 40; gHBSS: Hanks’ Balanced Salt Solution; GO: gene ontology; IFN-γ: IFN-gamma; LC3: mammalian microtubule-associated protein light chain 3; LAP; LC3-associated phagocytosis; LECA: last eukaryotic common ancestor; 3-MA: 3-methyladenine; MTOR; Mechanistic target of rapamycin kinase; MDC: monodansylcadaverine; NDP52: nuclear dot protein 52; PAAR: Plasmodium-Associated Autophagy-Related response; PE: phosphatidylethanolamine: PCD: programmed cell death; PND: programmed nuclear death; PtdIns3K: class III phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol 3-phosphate; PV: parasitophorous vacuole; PVM: parasitophorous vacuole membrane; SNARE: soluble N-ethylmaleimide-sensitive-factor attachment receptor; SQSTM1/p62: sequestosome-1; TEM: transmission electron microscopy; TNF-α: tumor necrosis factor-alpha; TVN: tubovesicular network; Ub: ubiquitin; UPS: ubiquitin-proteasome system; Vps: vacuolar protein sorting.

Recurrent myopericarditis is the acute inflammation of the pericardium and myocardium that relapses after a symptom-free interval of 4 to 6 weeks. A thorough differential diagnosis is necessary to identify uncommon causes that may have therapeutic and prognostic importance. These include autoinflammatory diseases, which can present as recurrent myopericarditis in genetically predisposed or impaired-immunity individuals. We present a 33-year-old male with polyclonal hypogammaglobulinemia and six episodes of myopericarditis, in which the diagnosis of a probable autoinflammatory syndrome was established. Targeted treatment based on the pathophysiological mechanismswas started with immunoglobulins and anakinra, with favourable clinical and serological outcome with no relapses. Organ-specific autoinflammatory diseases with myocardial involvement may be associated with life-threatening complications. The role of multidisciplinary care and a diagnostic approach focused on the pathophysiology of the disease could be the most important thing for early treatment to improve the prognosis and quality of life of our patients.