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Suicide stands as one of the leading causes of non-accidental death among adolescents and young adults. The Integrated Motivational–Volitional Model (IMV) of suicidal behavior identifies feelings of defeat and entrapment as pivotal factors in the complex dynamics underlying suicidal behaviors. Additionally, depressive symptomatology plays a crucial role in the development of these behaviors. The aim of this work was to provide a systematic review of the scientific literature on the association of three risk factors—entrapment, defeat, and depressive symptomatology—with suicidal ideation in the adolescent and young adult population and to test a tentative theoretical model. The databases used were PubMed, Web of Science, and ProQuest. Primary studies were selected that examined the role of entrapment, defeat, and depressive symptomatology in suicidal ideation among adolescents and young adults (ages 10–35). Additionally, a model based on structural equation modeling was analyzed to assess the relationships between entrapment, defeat, and depressive symptomatology and suicidal ideation. Eleven studies met the established inclusion criteria. The results showed defeat and entrapment to be associated with depressive symptomatology and suicidal ideation, regardless of the country studied. Additionally, the model indicates that entrapment and defeat lead to depressive symptomatology, which in turn contributes to the occurrence of suicidal ideation. These findings suggest that defeat and entrapment could be universal factors in explaining suicidal behavior in adolescents and young adults. Consequently, the results of this work may contribute to the development of strategies for preventing suicidal ideation in this population. [ABSTRACT FROM AUTHOR]

Suicide is one of the leading causes of death worldwide, affecting numerous individuals close to the person who died by suicide, including family members, friends, and colleagues. Those affected by the suicide of someone are referred to as "suicide survivors", and the psychological consequences they face are particularly severe. One of these consequences is grief, which is more complicated in survivors of suicide compared with those grieving deaths from other causes, mainly because of the stigma that continues to surround them. Therefore, psychotherapeutic intervention for suicide loss survivors is crucial. This study examines the efficacy of cognitive-behavioral programs for addressing grief and other related variables in suicide loss survivors. The search was conducted in databases including Psycinfo, Academic Search Premier, Medline, APA PsycArticles, E-Journals, Scopus, and PubMed. Five randomized controlled trials were selected, one of which focused exclusively on minors. The results reveal that cognitive-behavioral therapy is effective, although the methodological quality of these studies is not adequate, and the representativeness of the samples is very low. More RCTs are needed on the application of cognitive-behavioral programs to treat grief in suicide loss survivors. [ABSTRACT FROM AUTHOR]

The Water Framework Directive (Directive 2000/60/EC) emphasises the need for simple tools and studies to characterise aquatic ecosystems. A wide range of methods has been developed, including different groups of biota and different taxonomic resolutions. Among these, the abundance biomass comparison (ABC) method is an important methodology widely used in marine benthic systems and well-founded from the ecological point of view. This method - with a slight modification using genera and families instead of species - was applied in a Mediterranean river (Eliche-Frío, northeast of Andalusia, Spain) using the macroinvertebrate community, together with the Margalef richness index and the Iberian BioMonitoring Working Party (IBMWP) to determine the quality of the water. The obtained results show the suitability of the ABC curves method to analyse the macroinvertebrate community and estimate the ecological status of river ecosystems. Although both, the genus and family aggregations, showed a similar trend, the values obtained with the family level indicate a worse state of contamination than those shown with the genus level. The comparison between genus and family levels with other biological indices shows that the evaluation obtained with family aggregation is more similar to those obtained with the Margalef and IBMWP indices than the evaluation based on genera; therefore, we could conclude that this level of taxonomic resolution is adequate for the use of the ABC method in assessing the ecological status of Mediterranean rivers. [ABSTRACT FROM AUTHOR]

Viruses are an abundant component of aquatic systems, but their detection and quantification remain a challenge. Virophages co-replicate with giant viruses in the shared host cell, and can inhibit the production of new giant virus particles, thereby increasing the survival of the infected host population. Here, we present a protocol for Droplet Digital PCR (ddPCR) to quantify simultaneously giant virus and virophage in a mixed sample, enabling the rapid, culture-free and high throughput detection of virus and virophage. As virophage can be present as free virus particles or integrated into the virus host's genome as well as associated with organic particles, we developed a simple method that enables discrimination between free and particle-associated virophages. The latter include aggregated virophage particles as well as virophage integrated into the host genome. We used, for our experiments, a host-virus-virophage system consisting of Cafeteria burkhardae, CroV and mavirus. Our results show that ddPCR can be an efficient method to quantify virus and virophage, and we discuss potential applications of the method for studying ecological and evolutionary processes of virus and virophages. [ABSTRACT FROM AUTHOR]

Chemicals do not occur alone in the environment but most ecotoxicological assessments target the effect of single chemicals on aquatic communities and the establishment of legal limits is based on them. The present study assesses how plankton communities respond to single and mixture treatments of copper sulphate and ammonium nitrate where both agrochemical concentrations are below legal limits. Twenty-five microcosms were used to assess the effects of four treatments (n = 5): (1) low nitrate (L) of 25 mg L−1; (2) high nitrate (H) of 50 mg L−1; (3) copper treatment (CU) of 0.04 mg L−1 of copper; and (4) interaction treatment (I) of 50 mg L−1 of nitrate applied together with 0.04 mg L−1 of copper, and the controls (C). Plankton abundance, phytoplankton biovolume and zooplankton community structure (changes in the diversity and richness) were used as structural endpoints, and oxygen production and litter decomposition as functional indicators. Overall, results show no effect on the plankton community exposed to agrochemical under legal limits in single neither in mixture treatments. Only by the end of the experiment, total zooplankton abundance shows differences between interaction treatment (I) and the rest of the treatments and controls. Concretely, the interaction treatment suggests how a nutrient enhancement from ammonium nitrate addition may counterbalance the toxic effect of copper sulphate on zooplankton, most likely as a result of higher phytoplankton availability that positively influences zooplankter survival. Both drastic and subtle effects on communities are relevant for disentangling how chemicals interact under European current legal limits. Nitrate-copper mix within legal limits resulted on higher zooplankton abundance by the end of the experiment. It is explained by nutrient enhancement what may counterbalance the copper toxicity on zooplankton, most likely increasing phytoplankton availability. Consequently, studies on assumed safe toxicant mixtures are needed as subtle effects can have relevant consequences on communities. [ABSTRACT FROM AUTHOR]

Stem cells of the Drosophila midgut (ISCs) are the only mitotically dividing cells of the epithelium and, therefore, presumably the only epithelial cells that require functional kinetochores for microtubule spindle attachment during mitosis. The histone variant CENP-A marks centromeric chromatin as the site of kinetochore formation and spindle attachment during mitotic chromosome segregation. Here, we show that centromeric proteins distribute asymmetrically during ISC division. Whereas newly synthesized CENP-Amammalianintestine is enriched in differentiating progeny, CENP-C is undetectable in these cells. Remarkably, CENP-A persists in ISCs for weeks without being replaced, consistent with it being an epigenetic mark responsible for maintaining stem cell properties. Furthermore, CENP-A and its loading factor CAL1 were found to be essential for post-mitotic, differentiating cells; removal of any of these factors interferes with endoreduplication. Taken together, we propose two additional roles of CENP-A: to maintain stem cell- unique properties and to regulate post-mitotic cells. [ABSTRACT FROM AUTHOR]

More field relevant ecological assessments, apart from single species tests using standard species, are needed to better predict agrochemical effects at higher ecosystems levels. Therefore, an experiment using a non-target aquatic community was used to test the hypothesis of the negative effect of a single pulse of copper sulfate on plankton abundance, structure, richness and diversity endpoints. Microcosms (20 l volume) were established during 21 days of experimentation, using six replicates for controls and with two concentrations of copper sulfate (High treatment, H: 20 µg Cu l−1; and Low treatment, L: 2 µg Cu l−1), both within the copper legal threshold following the Water Framework Directive (2000). The general lineal model found significant differences at the phytoplankton abundance endpoint at the end of the experiment, with an increase of phytoplankton abundance in L treatments dominated by the smaller cell size class. The principal response curve on zooplankton data, despite being insignificant, pointed out some dissimilarities in abundance and structure between treatments and controls: treatments showed lower abundances and were richer in cladocerans and copepods than the control microcosm where rotifers and nauplii were dominant. This indicated that trends change in community structure due to the effects of copper sulfate, and that even if the copper concentrations under study were within legal limits, they showed potential to induce changes in planktonic communities. [ABSTRACT FROM AUTHOR]

Squalene synthase (SQS) catalyzes the first committed step of the sterol biosynthetic pathway. A full-length Arabidopsis thaliana SQS cDNA has been isolated by combining library screening and PCR-based approaches. Arabidopsis SQS is encoded by a small gene family of two genes (SQS1 and SQS2) which are organized in a tandem array. SQS1 and SQS2 have an identical organization with regard to intron positions and exon sizes and encode SQS isoforms showing a high level of sequence conservation (79% identity and 88% similarity). The isolated cDNA has been assigned to the SQS1 gene product, SQS1. RNA blot analysis has shown that the 1.6-kb SQA1 mRNA is detected in all plant tissues analyzed (inflorescenses, leaves, stems and roots) although the transcript is especially abundant in roots. Arabidopsis SQS1 isoform is unable to complement the SQS-defective Saccharomyces cerevisiae strain 5302, although SQS activity was detected in the microsomal fraction of the transformed yeast strain. However, a chimeric SQS resulting from the replacement of the 66 C-terminal residues of the Arabidopsis enzyme by the 111 C-terminal residues of the Schizosaccharomyces pombe enzyme was able to confer ergosterol prototrophy to strain 5302. Labeling studies using [3H]famesyl-P2 and microsomal fractions obtained from yeast strains expressing either Arabidopsis SQS1 or chimeric Arabidopsis/S. pombe SQS derivatives indicated that the C-terminal region of the enzyme is involved in the channeling of squalene through the yeast sterol pathway. [ABSTRACT FROM AUTHOR]

Background: The Latin American (LA) region is still facing an ongoing epidemiological transition and shows a complex public health scenario regarding non-communicable diseases (NCDs). A healthy diet and consumption of specific food groups may decrease the risk of NCDs, however there is a lack of dietary intake data in LA countries. Objective: Provide updated data on the dietary intake of key science-based selected food groups related to NCDs risk in LA countries. Design: ELANS (Latin American Study of Nutrition and Health) is a multicenter cross-sectional study assessing food consumption from an urban sample between15 to 65 years old from 8 LA countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru, and Venezuela). Two 24-HR were obtained from 9,218 individuals. The daily intake of 10 food groups related to NCDs risk (fruits; vegetables; legumes/beans; nuts and seeds; whole grains products; fish and seafood; yogurt; red meat; processed meats; sugar-sweetened beverages (ready-to-drink and homemade)) were assessed and compared to global recommendations. Results: Only 7.2% of the overall sample reached WHO's recommendation for fruits and vegetables consumption (400 grams per day). Regarding the dietary patterns related to a reduced risk of NCDs, among the overall sample legumes and fruits were the food groups with closer intake to the recommendation, although much lower than expected (13.1% and 11.5%, respectively). Less than 3.5% of the sample met the optimal consumption level of vegetables, nuts, whole grains, fish and yogurt. Largest country-dependent differences in average daily consumption were found for legumes, nuts, fish, and yogurt. Mean consumption of SSB showed large differences between countries. Conclusion: Diet intake quality is deficient for nutrient-dense food groups, suggesting a higher risk for NCDs in the urban LA region in upcoming decades. These data provide relevant and up-to-date information to take urgent public health actions to improve consumption of critically foods in order to prevent NCDs. [ABSTRACT FROM AUTHOR]

Tripartite biotic interactions are inherently complex, and the strong interdependence of species and often one-sided exploitation can make these systems vulnerable to extinction. The persistence of species depends then on the balance between exploitation and avoidance of exploitation beyond the point where sustainable resource use is no longer possible. We used this general prediction to test the potential role of trait evolution for persistence in a tripartite microbial system consisting of a marine heterotrophic flagellate preyed upon by a giant virus, which in turn is parasitized by a virophage. Host and virophage may benefit from this interaction because the virophage reduces the harmful effects of the giant virus on the host population and the virophage can persist integrated into the host genome when giant viruses are scarce. We grew hosts and virus in the presence and absence of the virophage over ∼280 host generations and tested whether levels of exploitation and replication in the giant virus and/or virophage population evolved over the course of the experiment, and whether the changes were such that they could avoid overexploitation and extinction. We found that the giant virus evolved toward lower levels of replication and the virophage evolved toward increased replication but decreased exploitation of the giant virus. These changes reduced overall host exploitation by the virus and virus exploitation by the virophage and are predicted to facilitate persistence., Competing Interests: None declared., (© The Author(s) 2024. Published by Oxford University Press.)

Giant viruses can control their eukaryotic host populations, shaping the ecology and evolution of aquatic microbial communities. Understanding the impact of the viruses' own parasites, the virophages, on the control of microbial communities remains a challenge. Most virophages have two modes of infection. They can exist as free particles coinfecting host cells together with the virus, where they replicate while inhibiting viral replication. Virophages can also integrate into the host genome, replicate through host cell division and remain dormant until the host is infected with a virus, leading to virophage reactivation and replication without inhibiting viral replication. Both infection modes (reactivation vs. coinfection) occur within host-virus-virophage communities, and their relative contributions are expected to be dynamic and context dependent. The consequences of this dynamic regime for ecological and evolutionary dynamics remain unexplored. Here, we test whether and how the relative contribution of virophage infection modes influences the ecological dynamics of an experimental host-virus-virophage system and the evolutionary responses of the virophage. We indirectly manipulated the level of virophage (Mavirus) integration into the host (Cafeteria burkhardae) in the presence of the giant Cafeteria roenbergensis virus. Communities with higher virophage integration were characterized by lower population densities and reduced fluctuations in host and virus populations, whereas virophage fluctuations were increased. The virophage evolved toward lower inhibition and higher replication, but the evolution of these traits was weaker with higher virophage integration. Our study shows that differences in the virophage infection modes contributes to the complex interplay between virophages, viruses and hosts., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

Regulation of chromatin structures is important for the control of DNA processes such as gene expression, and misregulation of chromatin is implicated in diverse diseases. Covalent post-translational modifications of histones are a prominent way to regulate chromatin structure and different chromatin regions bear their specific signature of histone modifications. The composition of centromeric chromatin is significantly different from other chromatin structures and mainly defined by the presence of the histone H3-variant CENP-A. Here we summarize the composition of centromeric chromatin and what we know about its differential regulation by post-translational modifications.