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BACKGROUND: Functional recovery remains a core clinical objective for patients with bipolar disorder (BD). Sociodemographic, clinical, and neurocognitive variables are associated with long-term functional impairment, yet the impact of sex differences is unclear. Functional remediation (FR) is a validated intervention aimed at achieving functional recovery in BD. The present study assessed the effect of sex differences of FR on psychosocial functioning at post-treatment (6-months) and 12-month follow-up (FUP). To the best of our knowledge, this is the first study to explore the role of sex as a factor in the efficacy of FR. METHODS: 157 participants with BD were randomly assigned to either FR (N = 77) or treatment as usual group (80). Clinical, sociodemographic, neuropsychological, and functional data were obtained using a comprehensive assessment battery. Sex differences were explored via a general linear model (GLM) for repeated measures to compare the effect of sex on the intervention over time (6 months and FUP). RESULTS: Results demonstrated that FR benefits both sexes, males (p = 0.001; d' = 0.88) and females (p = 0.04; d' = 0.57), at 6 months suggesting a generalized functional improvement. Conversely, at 12-month FUP sex differences were observed only in males (p = 0.005; d' = 0.68). CONCLUSIONS: FR is a beneficial intervention for males and females after treatment, suggesting that there are no relevant distinct needs. Females may benefit from ongoing psychosocial functioning booster sessions after the intervention to maintain original improvements. Future research exploring sex differences could help to identify strategies to offer personalized FR intervention approaches in individuals with BD.
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Barometric pressure is an environmental factor involved in the modulation of a variety of activities in insects. Generally, a drop in barometric pressure precedes the arrival of weather conditions that can affect insect activities and life expectancy. We simulated different scenarios of pressure drop in a modified hermetic chamber and studied their influence on the host-seeking behaviour of the larvae of the robber fly Mallophora ruficauda using air stationary olfactometers. In addition, we studied whether larval density modulates orientation to the host under the same scenarios of pressure drop. We found that motivation to search for hosts is affected by the same slope of pressure drop in both low- and high-density larvae. However, larval density modulates the onset of the responses to pressure decrease, as low-density larvae stop searching for hosts more quickly than high-density larvae. This result reflects an avoidance strategy according to which low-density larvae would have a reduced host range and higher risk of mortality and fewer chances to find a suitable host under adverse pressure conditions. Low-density larvae, known to prefer healthy hosts, do not search for parasitized hosts under normal pressure conditions nor under a range of pressure drops, strongly suggesting that host selectivity is not modulated by barometric pressure. This study paves the way to a better understanding of the changes in crucial insect behaviours induced by weather conditions, and provides more knowledge about the risk factors likely to affect insect survival in the context of foraging ecology.
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Dípteros , Larva , Animales , Larva/fisiología , Larva/crecimiento & desarrollo , Dípteros/fisiología , Presión Atmosférica , Densidad de Población , Interacciones Huésped-Parásitos , Conducta Alimentaria/fisiologíaRESUMEN
This study tackles the growing global concern about municipal waste management, particularly in cities like the Grand Guayaquil Metropolitan Area (GGA). Through realistic field studies on in situ household waste generation and geographic information system (GIS) tools, this work offers a framework to predict the quantities and types of recyclable household waste for any metropolitan area in Latin America. Over 4 weeks, students collected, sorted and weighed recyclable waste types, including plastic, paper, metal, glass and fabric, from 776 sampled household of the GGA. ArcGIS survey tool identified household locations and allowed to survey different socio-demographic features. With the help of ArcGIS interpolation method, the total household waste generation for GGA was predicted, and the classification of the different types of recyclable waste was also spatially distributed for the study area. The report identified notable trends in plastic waste, specifically polyethylene terephthalate waste's steady prevalence and 42% growth rate, emphasizing the importance of enhanced recycling techniques. Spatial density maps showed a heterogeneous waste distribution across the GGA, emphasizing locations with higher waste output. This study demonstrates that improving recyclable waste collection can be accomplished with a moderately cheap expenditure by collaborating with academia to overcome knowledge gaps. This strategy provides opportunities to mitigate the environmental impacts of poor waste management.
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Ciudades , Reciclaje , Administración de Residuos , Administración de Residuos/métodos , Sistemas de Información Geográfica , Composición Familiar , Plásticos , Residuos Sólidos/análisis , Eliminación de Residuos/métodos , Eliminación de Residuos/estadística & datos numéricos , Residuos/estadística & datos numéricos , América LatinaRESUMEN
Bulimia nervosa (BN) and other specific feeding or eating disorders with subthreshold BN symptoms (OSFED-BN) are characterized by recurrent binge eating episodes accompanied by compensatory behaviors, including excessive exercise. We aimed to examine the role of compensatory exercise on several clinical disorder-related variables and the treatment outcomes. The sample included 478 patients diagnosed with either BN or OSFED-BN admitted for a 16-week eating disorder-specific treatment program. A battery of questionnaires was administered to evaluate eating and general psychopathology, and personality traits. Other clinical disorder-related data, including levels of compensatory exercise, were assessed through a semi-structured clinical interview. Between-group comparisons of compensatory exercise levels were analyzed, as a predictive model of risk of poor treatment outcomes. Path analysis was conducted using structural equation models to estimate the direct and indirect effects between the main variables. Higher levels of self-reported compensatory exercise were associated with greater eating psychopathology, general psychopathology, and more dysfunctional personality traits and were a predictor of poor treatment outcomes. Additionally, these levels achieved a mediating role in several paths contributing to a higher likelihood of a poor outcome. Further research is required to determine how psychotherapeutic approaches can be optimized to adequately include adaptive exercise for these patients.
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Bulimia Nerviosa , Ejercicio Físico , Humanos , Bulimia Nerviosa/terapia , Bulimia Nerviosa/psicología , Femenino , Adulto , Resultado del Tratamiento , Adulto Joven , Encuestas y Cuestionarios , Masculino , Adolescente , PersonalidadRESUMEN
Physical education classes can be a place where both bullying and harassment take place, and a powerful strategy is needed to prevent it. The present study analyses bullying and students' behaviour as active or passive observers in a general educational context and physical education lessons. A sample of 958 adolescents aged 12 to 18 was studied. A questionnaire was used to analyse the victimisation and the bullying and behaviour observed. The results showed a lower incidence rate than that observed in other studies in physical education classes with a higher level of perpetration by boys than by girls and a more active rejection of aggression by victims and girls. On the other hand, passive attitudes were greater among perpetrators and boys. The observers' attitudes were similar in both contexts. The scenario in which this subject takes place could reduce the risk of these phenomena occurring. Therefore, physical education teachers should analyse these behaviours and intervene, especially when creating awareness in boys.
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BACKGROUND: Social isolation measures by the COVID-19 pandemic have impacted teaching work. In an "Emergency Remote Teaching" (ERT) context, it is relevant to investigate the factors that affect teachers' self-efficacy. METHODS: A total of 289 teachers from schools in southern Spain have participated in this study. They have been asked about their levels of burnout, engagement, and resilience. Comparisons were made by groups in accordance with sex, type of center they belonged to, school social context, and educational level in which the teacher taught. Using a Structural Equations Model, the multivariate relationships between the variables related to burnout, engagement, and resilience were described. RESULTS: During the ERT, teachers' self-efficacy was influenced by the 3 factors: burnout-exhaustion and cynicism-engagement, and resilience. During the ERT, the teachers in semi-private and private centers showed greater self-efficacy. In turn, the teachers in childhood and primary education showed a significantly higher level of work engagement than the teachers in compulsory and post-compulsory secondary education. CONCLUSIONS: The results in relation to ERT are discussed in the context of the exceptionality and universal globality of the pandemic phenomenon and the complex self-perception of the social value of the teaching function.
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Agotamiento Profesional , COVID-19 , Resiliencia Psicológica , Maestros , Autoeficacia , Humanos , COVID-19/psicología , COVID-19/epidemiología , Maestros/psicología , Agotamiento Profesional/psicología , Agotamiento Profesional/epidemiología , Femenino , Masculino , España/epidemiología , Adulto , SARS-CoV-2 , Persona de Mediana Edad , Educación a Distancia , Compromiso Laboral , PandemiasRESUMEN
Autophagy is a central degradative pathway highly conserved among eukaryotes, including microalgae, which remains unexplored in extremophilic organisms. In this study, we described and characterized autophagy in the newly identified extremophilic green microalga Chlamydomonas urium, which was isolated from an acidic environment. The nuclear genome of C. urium was sequenced, assembled and annotated in order to identify autophagy-related genes. Transmission electron microscopy, immunoblotting, metabolomic and photosynthetic analyses were performed to investigate autophagy in this extremophilic microalga. The analysis of the C. urium genome revealed the conservation of core autophagy-related genes. We investigated the role of autophagy in C. urium by blocking autophagic flux with the vacuolar ATPase inhibitor concanamycin A. Our results indicated that inhibition of autophagic flux in this microalga resulted in a pronounced accumulation of triacylglycerols and lipid droplets (LDs). Metabolomic and photosynthetic analyses indicated that C. urium cells with impaired vacuolar function maintained an active metabolism. Such effects were not observed in the neutrophilic microalga Chlamydomonas reinhardtii. Inhibition of autophagic flux in C. urium uncovered an active recycling of LDs through lipophagy, a selective autophagy pathway for lipid turnover. This study provided the metabolic basis by which extremophilic algae are able to catabolize lipids in the vacuole.
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Autofagia , Chlamydomonas , Metabolismo de los Lípidos , Fotosíntesis , Chlamydomonas/metabolismo , Fotosíntesis/efectos de los fármacos , Extremófilos/metabolismo , Gotas Lipídicas/metabolismo , Vacuolas/metabolismo , Filogenia , Triglicéridos/metabolismo , MacrólidosRESUMEN
The DDR1 locus is associated with the diagnosis of schizophrenia and with processing speed in patients with schizophrenia and first-episode psychosis. Here, we investigated whether DDR1 variants are associated with bipolar disorder (BD) features. First, we performed a caseâcontrol association study comparing DDR1 variants between patients with BD and healthy controls. Second, we performed linear regression analyses to assess the associations of DDR1 variants with neurocognitive domains and psychosocial functioning. Third, we conducted a mediation analysis to explore whether neurocognitive impairment mediated the association between DDR1 variants and psychosocial functioning in patients with BD. Finally, we studied the association between DDR1 variants and white matter microstructure. We did not find any statistically significant associations in the caseâcontrol association study; however, we found that the combined genotypes rs1264323AA-rs2267641AC/CC were associated with worse neurocognitive performance in patients with BD with psychotic symptoms. In addition, the combined genotypes rs1264323AA-rs2267641AC/CC were associated with worse psychosocial functioning through processing speed. We did not find correlations between white matter microstructure abnormalities and the neurocognitive domains associated with the combined genotypes rs1264323AA-rs2267641AC/CC. Overall, the results suggest that DDR1 may be a marker of worse neurocognitive performance and psychosocial functioning in patients with BD, specifically those with psychotic symptoms.
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Trastorno Bipolar , Receptor con Dominio Discoidina 1 , Funcionamiento Psicosocial , Trastornos Psicóticos , Humanos , Trastorno Bipolar/genética , Trastorno Bipolar/fisiopatología , Masculino , Femenino , Adulto , Receptor con Dominio Discoidina 1/genética , Receptor con Dominio Discoidina 1/metabolismo , Trastornos Psicóticos/genética , Estudios de Casos y Controles , Genotipo , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Sustancia Blanca , Pruebas Neuropsicológicas , Esquizofrenia/genética , Esquizofrenia/fisiopatología , Velocidad de ProcesamientoRESUMEN
Chemical repellents play a crucial role in personal protection, serving as essential elements in reducing the transmission of vector-borne diseases. A biorational perspective that extends beyond the olfactory system as the classical target may be a promising direction to move. The taste system provides reliable information regarding food quality, helping animals to discriminate between nutritious and potentially harmful food sources, often associated with a bitter taste. Understanding how bitter compounds affect feeding in blood-sucking insects could unveil novel molecules with the potential to reduce biting and feeding. Here, we investigated the impact of two naturally occurring bitter compounds, caffeine and quinine, on the feeding decisions in female Aedes aegypti mosquitoes at two distinctive phases: (1) when the mosquito explores the biting substrate using external taste sensors and (2) when the mosquito takes a sip of food and tastes it using internal taste receptors. We assessed the aversiveness of bitter compounds through both an artificial feeding condition (artificial feeder test) and a real host (arm-in-cage test). Our findings revealed different sensitivities in the external and internal sensory pathways responsible for detecting bitter taste in Ae. aegypti. Internal detectors exhibited responsiveness to lower doses compared to the external sensors. Quinine exerted a more pronounced negative impact on biting and feeding activity than caffeine. The implications of our findings are discussed in the context of mosquito food recognition and the potential practical implications for personal protection.
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Aedes , Cafeína , Conducta Alimentaria , Quinina , Gusto , Animales , Femenino , Cafeína/farmacología , Aedes/fisiología , Conducta Alimentaria/efectos de los fármacosRESUMEN
BACKGROUND: The influence of bullying on physical activity beyond school time is uncertain, as it can vary widely in terms of type, modality, duration, adult supervision, and objectives. METHODS: This study aims to analyze the relationship between school bullying and the type of physical activity practised. To this end, a descriptive study was made of 2025 pre- and adolescents aged between 10 and 19 years, reporting on their participation in victimisation and perpetration. The EBIPQ and PAQ-A were used. An analysis of the relationships between these variables was carried out according to gender and type of activity practised. RESULTS: The results showed a higher rate of victimisation in boys who did not practise physical activity. Meanwhile, perpetration was higher in those who practised organised physical activity, especially in boys. Depending on the type of physical activity, the higher levels of both victimisation and perpetration of those who practised wrestling activities stand out in comparison with other groups. CONCLUSIONS: It could be stated that physical activity may be a protective factor against bullying victimisation, especially in boys. However, participation in organised physical activity activities may be related to higher perpetration in this sample in adolescent boys.
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ABSTRACT: In the context of the global vaccination campaign against COVID-19, several cases of postvaccinal Guillain-Barré syndrome (GBS) were reported. Whether a causal relationship exists between these events has yet to be established. We investigated the clinical and electromyographic characteristics of patients who developed GBS after COVID-19 vaccination and compare these with findings in patients with GBS, without a history of recent vaccination. We included 91 cases between March 2020 and March 2022, treated at 10 referral hospitals of Buenos Aires, Argentina. Of these, 46 had received vaccination against COVID-19 within the previous month. Although Medical Research Council sum-scores were similar in both groups (median 52 vs. 50; P = 0.4), cranial nerve involvement was significantly more frequent in the postvaccination group (59% vs. 38%; P = 0.02), as was bilateral facial paralysis (57% vs. 24%; P = 0.002). No differences were found in clinical or neurophysiological phenotypes, although 17 subjects presented the variant of bilateral facial palsy with paresthesias (11 vs. 6; P = 0.1); nor were significant differences observed in length of hospital stay or mortality rates. Future vaccine safety monitoring and epidemiology studies are essential to demonstrate any potential causal relationship between these events.
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COVID-19 , Síndrome de Guillain-Barré , Humanos , Vacunas contra la COVID-19/efectos adversos , COVID-19/prevención & control , Síndrome de Guillain-Barré/epidemiología , Síndrome de Guillain-Barré/etiología , Estudios Retrospectivos , ParestesiaRESUMEN
INTRODUCTION: The cause of death can be attributed to malnutrition in 10-20% of cancer patients. Patients with sarcopenia present more chemotherapy toxicity, less progression-free time, less functional capacity and more surgical complications. Antineoplastic treatments have a high prevalence of adverse effects that compromise nutritional status. The new chemotherapy agents present direct toxicity on the digestive tract (nausea, vomiting, diarrhoea and/or mucositis). We present the frequency of adverse effects with nutritional impact of the most frequent chemotherapy agents used in the treatment of solid tumours, as well as strategies for early diagnosis and nutritional treatment. MATERIAL AND METHODS: Review of commonly used cancer treatments (cytotoxic agents, immunotherapy, targeted therapies) in colorectal, liver, pancreatic; lung, melanoma, bladder, ovary, prostate and kidney cancer. The frequency (%) of gastrointestinal effects, and those of grade ≥3 are recorded. A systematic bibliographic search was carried out in PubMed, Embase, UpToDate, international guides and technical data sheets. RESULTS: They are shown in the form of tables in which the drugs appear together with the probability that they present any digestive adverse effect and the percentage of serious adverse effects (Grade ≥ 3). DISCUSSION: Antineoplastic drugs are associated with a high frequency of digestive complications with nutritional repercussions, which can reduce QoL and cause death as a result of malnutrition or due to the limiting effect of suboptimal treatments, closing the malnutrition-toxicity loop. It is necessary to inform the patient about the risks and establish local protocols regarding the use of antidiarrheal drugs, antiemetics and adjuvants in the management of mucositis. We propose action algorithms and dietary advice that can be used directly in clinical practice, to prevent the negative consequences of malnutrition.
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Antineoplásicos , Desnutrición , Mucositis , Neoplasias , Masculino , Femenino , Humanos , Estado Nutricional , Mucositis/inducido químicamente , Mucositis/complicaciones , Calidad de Vida , Antineoplásicos/efectos adversos , Neoplasias/complicaciones , Neoplasias/tratamiento farmacológico , Desnutrición/complicacionesRESUMEN
Autophagy is a catabolic process by which eukaryotic cells degrade and recycle unnecessary or damaged intracellular components to maintain cellular homeostasis and to cope with stress. The development of specific tools to monitor autophagy in microalgae and plants has been fundamental to investigate this catabolic pathway in photosynthetic organisms. The protein ATG8 is a widely used molecular marker of autophagy in all eukaryotes, including the model microalga Chlamydomonas reinhardtii. The drug concanamycin A, a specific inhibitor of vacuolar ATPase, has also been extensively used to block autophagic flux in the green lineage. In Chlamydomonas, inhibition of autophagic flux by concanamycin A has been shown to prevent the degradation of ribosomal proteins and the formation of lipid bodies under nitrogen or phosphorous starvation. Here, we detail how the abundance and lipidation state of ATG8 can be used to monitor autophagic flux in Chlamydomonas by western blot analysis.
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Chlamydomonas reinhardtii , Chlamydomonas , Microalgas , Chlamydomonas reinhardtii/metabolismo , Autofagia/fisiología , Macrólidos/farmacologíaRESUMEN
RESUMEN Objetivo Proponer una herramienta para identificar sectores de población que requieren mayor atención por parte de autoridades locales o gubernamentales en situaciones de crisis biológica, considerando los factores que influyen en la adherencia a las normas de minimización de riesgos. Metodología Se implementó un algoritmo de ordenamiento, tomando como referencia las restricciones de julio del 2021 en Ecuador. El contexto del estudio se resume en siete sectores urbanos de la ciudad de Guayaquil, con una población caracterizada por un nivel de educación promedio por debajo de la educación secundaria superior (70%) y más del 50% entre 20-34 años, con alguna ocupación en el medio de una economía popular debilitada. Siete factores de riesgo fueron identificados después de un análisis estructural de la hipótesis de adherencia (x2/gl=3,6; CFI≥0,91; TLI≥0,90; RMSEA≤0,05), basado en una muestra aleatoria de n=515 adultos viviendo en las áreas afectadas. Resultados El seguimiento de las normas está influenciado por la percepción del clima de seguridad, el riesgo percibido y el entendimiento del riesgo. El umbral de ordenamiento (h) permite establecer relaciones unidireccionales entre variables. Conclusiones Los resultados muestran que Vergeles, Norte y Fertisa representan los sectores con mayor prioridad de atención en materia de salud pública {A4,A5,A6}>{A2}>{A3}>{A1}>{A7}. Se requiere identificar más factores para garantizar una diferenciación óptima.
ABSTRACT Objective To propose a tool to identify local communities that require public health work priority, taking into account factors that influence adherence to risk minimization guidelines, especially in lock-down environments and unconventional workplaces. Methodology An ordering algorithm, based on the theory of uncertainty, was applied to classify population zones exhibiting high levels of infection and non-compliance with regulations in Guayaquil, during the last 'weekend' lockdown episode in July 2021. Seven urban sectors showed the highest number of infections (more than 70% of the local population): Vergeles (A1), Samanes (A2), Socio Vivienda (A3), Guasmo Norte (A4), Fertisa (A5), Alborada (A6), Urdesa (A7). Seven risk factors were identified after a path analysis of compliance hypothesis (x2/gl=3,6; CFI≥0,91; TLI≥0,90, RMSEA≤0,05), based on a random sample of n=515 adults living in the affected areas. Results Adherence to norms is influenced by the safety climate, perceived risk and risk understanding. The ordering threshold (h) leaded unidirectional relationships between variables. Conclusions: Adding more factors are believed to increases the differentiation path. The results showed that Vergeles, Norte and Fertisa were the areas with the highest priority for public health care {A4,A5,A6}>{A2}>{A3}>{A1}>{A7}.
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The target of rapamycin (TOR) protein kinase is a master regulator of cell growth in all eukaryotes, from unicellular yeast and algae to multicellular animals and plants. Target of rapamycin balances the synthesis and degradation of proteins, lipids, carbohydrates and nucleic acids in response to nutrients, growth factors and cellular energy to promote cell growth. Among nutrients, amino acids (AAs) and glucose are central regulators of TOR activity in evolutionary distant eukaryotes such as mammals, plants and algae. However, these organisms obtain the nutrients through totally different metabolic processes. Although photosynthetic eukaryotes can use atmospheric CO2 as the sole carbon (C) source for all reactions in the cell, heterotrophic organisms get nutrients from other sources of organic C including glucose. Here, we discuss the impact of autotrophic and heterotrophic metabolism on the nutrient regulation of TOR, focusing on the role of AAs and C sources upstream of this signaling pathway.
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Ácidos Nucleicos , Sirolimus , Animales , Dióxido de Carbono/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Plantas/metabolismo , Carbono/metabolismo , Glucosa/metabolismo , Nutrientes , Aminoácidos/metabolismo , Carbohidratos , Ácidos Nucleicos/metabolismo , Lípidos , MamíferosRESUMEN
SNF1-related protein kinase 1 (SnRK1), the plant ortholog of mammalian AMP-activated protein kinase/fungal (yeast) Sucrose Non-Fermenting 1 (AMPK/SNF1), plays a central role in metabolic responses to reduced energy levels in response to nutritional and environmental stresses. SnRK1 functions as a heterotrimeric complex composed of a catalytic α- and regulatory ß- and ßγ-subunits. SnRK1 is a multitasking protein involved in regulating various cellular functions, including growth, autophagy, stress response, stomatal development, pollen maturation, hormone signaling, and gene expression. However, little is known about the mechanism whereby SnRK1 ensures differential execution of downstream functions. Compartmentalization has been recently proposed as a new key mechanism for regulating SnRK1 signaling in response to stimuli. In this review, we discuss the multitasking role of SnRK1 signaling associated with different subcellular compartments.
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Proteínas Quinasas Activadas por AMP , Proteínas de Arabidopsis , Animales , Proteínas Quinasas Activadas por AMP/metabolismo , Estrés Fisiológico , Transducción de Señal , Saccharomyces cerevisiae/metabolismo , Plantas/genética , Plantas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Mamíferos/metabolismoRESUMEN
The aim of our study was to examine whether there are sex-based differences in the relationship between personality traits and hypothalamic-pituitary-adrenal (HPA) axis measures. A total of 106 healthy volunteers (56.6% women; age: 48.0 ± 15.8 years) were studied. The revised temperament and character inventory (TCI-R) and the Childhood Trauma Questionnaire (CTQ) were administered. HPA axis function was assessed using three dynamic measures: the cortisol awakening response (CAR), the diurnal cortisol slope, and the cortisol suppression ratio with 0.25 mg of dexamethasone (DSTR). Female sex was associated with an increased CAR and a more flattened diurnal cortisol slope, although a negative significant interaction between harm avoidance and female sex was found. Regarding the DSTR, perseverance was associated with increased cortisol suppression after dexamethasone; sex did not affect this association. Our study suggests that the relationship between specific personality traits (harm avoidance) and HPA axis measures (CAR, diurnal slope) differs according to sex.
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Sistema Hipotálamo-Hipofisario , Sistema Hipófiso-Suprarrenal , Adulto , Dexametasona , Femenino , Humanos , Hidrocortisona , Masculino , Persona de Mediana Edad , Personalidad , SalivaRESUMEN
Microalgae constitute a highly diverse group of photosynthetic microorganisms that are widely distributed on Earth. The rich diversity of microalgae arose from endosymbiotic events that took place early in the evolution of eukaryotes and gave rise to multiple lineages including green algae, the ancestors of land plants. In addition to their fundamental role as the primary source of marine and freshwater food chains, microalgae are essential producers of oxygen on the planet and a major biotechnological target for sustainable biofuel production and CO2 mitigation. Microalgae integrate light and nutrient signals to regulate cell growth. Recent studies identified the target of rapamycin (TOR) kinase as a central regulator of cell growth and a nutrient sensor in microalgae. TOR promotes protein synthesis and regulates processes that are induced under nutrient stress such as autophagy and the accumulation of triacylglycerol and starch. A detailed analysis of representative genomes from the entire microalgal lineage revealed that the highly conserved central components of the TOR pathway are likely to have been present in the last eukaryotic common ancestor, and the loss of specific TOR signaling elements at an early stage in the evolution of microalgae. Here we examine the evolutionary conservation of TOR signaling components in diverse microalgae and discuss recent progress of this signaling pathway in these organisms.
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Microalgas , Microalgas/metabolismo , Sirolimus/metabolismo , Transducción de Señal , Fotosíntesis , EucariontesRESUMEN
Deciphering the molecular mechanisms underlying the regulation of the ATG4 protease is essential to understand the regulation of ATG8 lipidation, a key step in the biogenesis of the autophagosome and hence in autophagy progression. Here, we describe two complementary approaches to monitor ATG4 proteolytic activity in the model green alga Chlamydomonas reinhardtii: an in vitro assay using recombinant ATG4 and recombinant ATG8 as substrate, and a cell-free assay using soluble total protein extract from Chlamydomonas and recombinant Chlamydomonas ATG8 as substrate. Both assays are followed by non-reducing SDS-PAGE and immuno-blot analysis. Given the high evolutionary conservation of the ATG8 maturation process, these assays have also been validated to monitor ATG4 activity in yeast using Chlamydomonas ATG8 as substrate.