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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.

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Anthropogenic activities generate a severe footprint at a global scale. Intensive agriculture is a global change driver that affects aquatic systems due to the discharge of pollutants. This situation can be modified or aggravated by other aspects, such as the disturbance history and other global change factors. Following our study line, it is necessary to evaluate how the disturbance history combined with temperature changes can affect the functioning of aquatic systems. The objectives of this study were divided into two phases. The objectives of phase 1 were to induce vulnerability in Daphnia magna populations through a disturbance history based on sublethal glyphosate concentration exposure under different temperature conditions (20 °C and 25 °C). In phase 2, vulnerability was assessed through the exposure to subsequent stressors (starvation, increased salinity and paracetamol) combined with changes in temperature. During the glyphosate exposure period in phase 1, differences were observed in the D. magna populations with respect to temperature, with lower abundance at 25 °C than at 20 °C. However, no differences were observed in abundance regarding glyphosate treatment. The results obtained in phase 2 with the new stressors combined with temperature changes in both directions, revealed stronger effects in vulnerable populations than in control populations. In addition, the temperature changes modulated the effects in the starvation and increased salinity tests. Agrochemical sublethal concentrations induce vulnerability in D. magna populations and inflicted temperature changes can act as a modulating factor for this vulnerability, showing the complexity in assessing the responses under the multiple scenarios associated with global change.

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Ecological risk assessment of chemicals focuses on the response of different taxa in isolation not taking ecological and evolutionary interplay in communities into account. Its consideration would, however, allow for an improved assessment by testing for implications within and across trophic levels and changes in the phenotypic and genotypic diversity within populations. We present a simple experimental system that can be used to evaluate the ecological and evolutionary responses to chemical exposure at microbial community levels. We exposed a microbial model system of the ciliate Tetrahymena thermophila (predator) and the bacterium Pseudomonas fluorescens (prey) to iron released from Magnetic Particles (MP-Fedis), which are Phosphorus (P) adsorbents used in lake restoration. Our results show that while the responses of predator single population size differed across concentrations of MP-Fedis and the responses of prey from communities differed also across concentration of MP-Fedis, the community responses (species ratio) were similar for the different MP-Fedis concentrations. Looking further at an evolutionary change in the bacterial preys' defence, we found that MP-Fedis drove different patterns and dynamics of defence evolution. Overall, our study shows how similar community dynamics mask changes at evolutionary levels that would be overlooked in the design of current risk assessment protocols where evolutionary approaches are not considered.

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Intensive agriculture is characterized by the application of multiple stressors that damage aquatic systems. Currently, ecotoxicological evaluations are considered insufficient to understand the environmental risks of stressor mixtures and their consequences in ecosystems. In addition, future global change scenarios could alter the predicted effects of agrochemicals in aquatic systems based on single exposures, making it necessary to consider the history of environmental disturbances that may result in vulnerability to subsequent environmental changes. The objectives of this study were to induce disturbance histories by exposure to sublethal glyphosate concentrations in microcosms and to assess whether this disturbance results in vulnerable populations using Daphnia magna as the target species. Populations were considered vulnerable if their sensitivity to new stressors (inanition, temperature and salinity) was higher than that of undisturbed populations. To induce disturbance history, microcosm aquatic communities (two cladocerans and one microalgae) were exposed to two glyphosate sublethal concentrations (below the No Observed Effect Concentration, NOEC values for D. magna, 0.1 and 1 mg L-1) in microcosms under controlled conditions in a culture chamber for 48 days. After this period, no significant differences were observed with respect to the control microcosms in the selected parameters (cladoceran abundance, microalgae cell abundance, microalgae colony formation, pH and dissolved oxygen). To test vulnerability, our target D. magna populations, which were previously exposed to different glyphosate treatments, were subjected to inanition, elevated temperature and salinity. Our results showed that D. magna populations with disturbance history performed worse in all the scenarios compared to the populations from undisturbed conditions. These results underscore the need to study how environmental disturbance history influences population responses to new and future stressors. Moreover, our findings raise concern regarding the sublethal effects of pesticides on aquatic populations.

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BACKGROUND: Evidence has shown that active transportation decreases obesity rates, but considering walking or cycling as separate modes could provide additional information on the health benefits in adolescents. This study aimed to examine the associations between walking and cycling as form active transportation and obesity indicators in Latin American adolescents. METHODS: Population-based study with 671 adolescents (mean age: 15.9 [standard deviation: 0.8] years) from eight countries participating in the Latin American Study of Nutrition and Health/Estudio Latino Americano Nutrition y Salud (ELANS). Walking and cycling for active transportation were measured using the International Physical Activity Questionnaire long version. Body mass index, waist circumference, neck circumference, and relative fat mass were used as obesity indicators. Associations were estimated using logistic regression models for the pooled data adjusted for country, sex, age, socio-economic levels, race/ethnicity, leisure-time physical activity and energy intake. RESULTS: Mean time spent walking and cycling was 22.6 (SD: 33.1) and 5.1 (SD: 24.1) min/day, respectively. The median values were 12.8 (IQR: 4.2; 25.7) and 0 (IQR: 0; 6.2) for walking and cycling. Participants reporting ≥ 10 min/week of walking or cycling for active transportation were 84.2% and 15.5%, respectively. Costa Rica (94.3% and 28.6%) showed the highest prevalence for walking and cycling, respectively, while Venezuela (68.3% and 2.4%) showed the lowest prevalence. There was no significant association between walking for active transportation and any obesity indicator. In the overall sample, cycling for ≥ 10 min/week was significantly associated with a lower likelihood of overweight/obesity based on BMI (OR: 0.86; 95%CI: 0.88; 0.94) and waist circumference (OR: 0.90; 95%CI: 0.83; 0.97) adjusted for country, sex, age, socio-economic level, race/ethnicity, leisure-time physical activity and energy intake compared to cycling for < 10 min/week. There were no significant associations between cycling for active transportation and neck circumference as well as relative fat mass. CONCLUSIONS: Cycling for active transportation was negatively associated with obesity indicators, especially body mass index and waist circumference. Programs for promoting cycling for active transportation could be a feasible strategy to tackle the high obesity rates in adolescents in Latin America. TRIAL REGISTRATION: ClinicalTrials.Gov NCT02226627. Retrospectively registered on August 27, 2014.

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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.

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Canonical Wnt signaling plays critical roles in development and tissue renewal by regulating ß-catenin target genes. Recent evidence showed that ß-catenin-independent Wnt signaling is also required for faithful execution of mitosis. However, the targets and specific functions of mitotic Wnt signaling still remain uncharacterized. Using phosphoproteomics, we identified that Wnt signaling regulates the microtubule depolymerase KIF2A during mitosis. We found that Dishevelled recruits KIF2A via its N-terminal and motor domains, which is further promoted upon LRP6 signalosome formation during cell division. We show that Wnt signaling modulates KIF2A interaction with PLK1, which is critical for KIF2A localization at the spindle. Accordingly, inhibition of basal Wnt signaling leads to chromosome misalignment in somatic cells and pluripotent stem cells. We propose that Wnt signaling monitors KIF2A activity at the spindle poles during mitosis to ensure timely chromosome alignment. Our findings highlight a function of Wnt signaling during cell division, which could have important implications for genome maintenance, notably in stem cells.

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BACKGROUND: Lifestyle acquired in youth can determine the individual's health. Constant vigilances in all aspects related to the health of the young population is essential, and evaluate their health parameters is important. The objective of this study was to describe and to compare food intake, physical activity (PA) practice, nutritional status and body composition between adolescents and young adults. METHODS: Four hundred seventy-six individuals from the Brazilian Study of Nutrition and Health (EBANS) were analyzed. Food intake was evaluated by applying two 24-h Dietary Recall. The PA and sitting time (ST) were measured by the International Physical Activity Questionnaire in minutes/week and metabolic equivalent task (METs). Body weight and waist circumference (WC) were measured. Body mass index (BMI) and waist circumference to height ratio (WHtR) were calculated. Mann-Whitney and Chi-Square tests were used. RESULTS: Energy and macronutrients intake, number of meals, and breakfast skippers weren't different between age groups. 48% of adolescents and 53% of young adults didn't meet the PA recommendation, and adolescents practiced more PA than young adults (total PA: p = 0.006; METs: p < 0.001; leisure PA: p = 0.001); the individuals who studied practiced more PA (total PA: p = 0.034; METs: p = 0.029; leisure PA: p < 0.001) and had ST significantly higher (p = 0.009) than those who worked. Almost 30% of adolescents and 45% of young adults had excess weight; presenting difference according to nutritional status, WC and WHtR (p < 0.001). CONCLUSION: There is a high prevalence of excess weight among young Brazilians and differences were observed between age groups regarding nutritional status, body composition and PA practice. TRIAL REGISTRATION: ClinicalTrials.Gov NCT02226627 . Retrospectively registered on August 27, 2014.

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The tumour suppressors RNF43 and ZNRF3 play a central role in development and tissue homeostasis by promoting the turnover of the Wnt receptors LRP6 and Frizzled (FZD). The stem cell growth factor R-spondin induces auto-ubiquitination and membrane clearance of ZNRF3/RNF43 to promote Wnt signalling. However, the deubiquitinase stabilising ZNRF3/RNF43 at the plasma membrane remains unknown. Here, we show that the USP42 antagonises R-spondin by protecting ZNRF3/RNF43 from ubiquitin-dependent clearance. USP42 binds to the Dishevelled interacting region (DIR) of ZNRF3 and stalls the R-spondin-LGR4-ZNRF3 ternary complex by deubiquitinating ZNRF3. Accordingly, USP42 increases the turnover of LRP6 and Frizzled (FZD) receptors and inhibits Wnt signalling. Furthermore, we show that USP42 functions as a roadblock for paracrine Wnt signalling in colon cancer cells and mouse small intestinal organoids. We provide new mechanistic insights into the regulation R-spondin and conclude that USP42 is crucial for ZNRF3/RNF43 stabilisation at the cell surface.

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Neuroinflammation is one of the most frequently studied topics of neurosciences as it is a common feature in almost all neurological disorders. Although the primary function of neuroinflammation is to protect the nervous system from an insult, the complex and sequential response of activated glial cells can lead to neurological damage. Depending on the type of insults and the time post-insult, the inflammatory response can be neuroprotective, neurotoxic, or, depending on the glial cell types, both. There are multiple pathways activated and many bioactive intermediates are released during neuroinflammation. One of the most common one is the kynurenine pathway, catabolizing tryptophan, which is involved in immune regulation, neuroprotection, and neurotoxicity. Different models have been used to study the kynurenine pathway metabolites to understand their involvements in the development and maintenance of the inflammatory processes triggered by infections. Among them, the parasitic infection Neospora caninum could be used as a relevant model to study the role of the kynurenine pathway in the neuroinflammatory response and the subset of cells involved.

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Inactivation by adding different phosphorus (P) adsorbents is one of the most frequently used methods for combating inland water eutrophication. The aim of this work was to assess the toxic effects of novel P adsorbents (magnetic particles, MPs) on the phytoplankton community. An outdoor microcosm experiment, containing lake water and surface sediment from a hypertrophic Mediterranean lake, was carried out following a factorial design (n = 5) with three different treatments: control (C), where no MPs were added; Treatment-Water (T-W) and Treatment-Sediment (T-S). In T-W and T-S treatments, MPs were added on the surface water layer and on the sediment, respectively, to obtain a final concentration of 1.4 g MP L-1. This concentration was based on both the sedimentary mobile P concentration of the study site and the maximum P adsorption capacity of the MPs, obtained from the literature. After 24 h of contact time, the MPs were removed using a magnetic rake. Physicochemical measurements and biological samples were taken after 24 h of exposure to the MPs and at different time points after such exposure (day 2, 7, 21, 35 and 70). Changes in phytoplankton community such as abundance (biovolume and Chla), species composition and taxonomic groups were assessed, as well as changes in the Shannon-Wiener diversity index. Additionally, the eutrophic metric Algae Group Index (AGI), one of the metrics proposed in the Water Framework Directive, was also calculated. Our results indicate that there is no strong evidence to infer that MPs caused an effect on the phytoplankton community, since no significant differences (GLM test; p > 0.05) were found between controls and treatments in any of the studied variables (phytoplankton taxonomic groups, AGI, Chla concentration, biovolume, diversity and community responses). Accordingly, MPs did not cause any toxic effects on the phytoplankton community of the lake, encouraging the use of MPs in a future whole-lake restoration strategy. However, if the final goal of the restoration plan is to combat nuisance cyanobacteria blooms, higher initial MPs doses or repeated MPs applications are required to achieve a reduction in P concentrations below biological thresholds in order to prevent algal blooms.

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Since aquatic ecosystems receive runoff of most anthropogenic pollutants, risk assessment tools and protocols have been developed in order to protect them. However, most ecological risk assessments focus on the study of single species exposed to a single chemical, overlooking the environmental reality of multiple chemical exposures and stresses over generations. To advance in realistic predictions of population and community changes, the environmental disturbance history should be considered. The aim of this study was to evaluate how environmental disturbance history (continuous expected sublethal exposure to one chemical for several generations) determines populations' responses to another stressors. The experiments were performed with Daphnia magna as model organisms. To create a disturbance history, dimethoate was used as first stressor at two different concentrations: medium (0.089 mg·L-1) and high (0.89 mg·L-1). The population exposed to medium concentration ("vulnerable population") showed no differences from the control population in the selected parameters (body size and reproductive success). Our interest in the vulnerable population was to determine whether, after a first stressor, the detected non-effect hides a population impairment, which might undermine populations' responses to future stressors. After 4 generations under dimethoate exposure, the vulnerable D. magna population was exposed to a second chemical stressor (glyphosate) and an environmental stressor (food scarcity) as compared to control. The vulnerable population showed both less resistance to glyphosate and less resistance to starvation, corroborating the hypothesis that a disturbance history of continuous expected sublethal chemical exposures undermines populations' responses to further chemical and environmental stressors.

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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.

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BACKGROUND: Epidemiological studies with dietary variables are complex methodologically, being the researcher responsible for anticipating, controlling, reducing and preventing methodological errors. Obesity accounts for almost one-third of the world's population and has consequences for childhood and adolescence. Multifactorial disorder must be faced in several aspects, being food and physical activity, modifiable risk factors. The EBANS aims to perform a diagnosis of the nutritional status of the Brazilian population from 15 to 65 years old, from all regions, and the parameters associated with obesity, with several possibilities of correlating data. METHODOLOGICAL PROCESS: Part of the ELANS study (n = 9218), the EBANS (n = 2000) has a weighted sample and data collection that allows: to evaluate the socioeconomic level of the population; perform a diagnosis of nutritional status (through anthropometric variables); to evaluate food intake (R24h and FFQ for beverages); and evaluate physical activity practice (IPAQ-long and accelerometer). METHODOLOGICAL OPPORTUNITIES: With national coverage, EBANS has the potential to compose regional analyzes, portray the current nutritional epidemiological condition, food consumption and physical activity pattern of the Brazilian population, at different life stages, and may have their data analyzed together or stratified, offering useful subsidies for the formulation of public policies. METHODOLOGICAL CHALLENGES: Each methodological step was designed to reduce errors and biases related to methodological challenges. CAAE REGISTRATION: 31670314.8.0000.5567. FINAL CONSIDERATIONS: Of great potential for future data analysis, EBANS tries to contribute to the generation of knowledge to foment policies and actions capable of changing the current obesity scenario.

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SUMMARY BACKGROUND: Epidemiological studies with dietary variables are complex methodologically, being the researcher responsible for anticipating, controlling, reducing and preventing methodological errors. Obesity accounts for almost one-third of the world's population and has consequences for childhood and adolescence. Multifactorial disorder must be faced in several aspects, being food and physical activity, modifiable risk factors. The EBANS aims to perform a diagnosis of the nutritional status of the Brazilian population from 15 to 65 years old, from all regions, and the parameters associated with obesity, with several possibilities of correlating data. METHODOLOGICAL PROCESS: Part of the ELANS study (n = 9218), the EBANS (n = 2000) has a weighted sample and data collection that allows: to evaluate the socioeconomic level of the population; perform a diagnosis of nutritional status (through anthropometric variables); to evaluate food intake (R24h and FFQ for beverages); and evaluate physical activity practice (IPAQ-long and accelerometer). METHODOLOGICAL OPPORTUNITIES: With national coverage, EBANS has the potential to compose regional analyzes, portray the current nutritional epidemiological condition, food consumption and physical activity pattern of the Brazilian population, at different life stages, and may have their data analyzed together or stratified, offering useful subsidies for the formulation of public policies. METHODOLOGICAL CHALLENGES: Each methodological step was designed to reduce errors and biases related to methodological challenges. CAAE REGISTRATION: 31670314.8.0000.5567. FINAL CONSIDERATIONS: Of great potential for future data analysis, EBANS tries to contribute to the generation of knowledge to foment policies and actions capable of changing the current obesity scenario.

RESUMO INTRODUÇÃO: Estudos epidemiológicos com variáveis dietéticas são complexos metodologicamente, e o pesquisador é responsável por antecipar, controlar, reduzir e prevenir erros metodológicos. A obesidade representa quase 1/3 da população mundial e agrega consequências que são observadas na infância e na adolescência. Desordem multifatorial deve ser enfrentada sob diversos aspectos, sendo alimentação e atividade física fatores de risco modificáveis. O EBANS se propõe a realizar um diagnóstico do estado nutricional da população brasileira de 15 a 65 anos, de todas as regiões, e dos parâmetros associados à obesidade, com diversas possibilidades de correlacionar dados. PROCESSO METODOLÓGICO: Parte do estudo ELANS (n=9218), o EBANS (n=2000) tem amostra ponderada e coleta de dados que permite: avaliar o nível socioeconômico da população; realizar diagnóstico do estado nutricional (por meio de variáveis antropométricas); avaliar consumo alimentar (R24h e QFA para bebidas); e avaliar prática de atividade física (IPAQ-longo e acelerômetro). OPORTUNIDADES METODOLÓGICAS: De abrangência nacional, o EBANS tem potencial para compor análises regionais, retratar a atual condição epidemiológica nutricional, de consumo alimentar e padrão de atividade física da população brasileira, em diferentes estágios da vida, podendo ter seus dados analisados em conjunto ou estratificados, oferecendo subsídios úteis para a formulação de políticas públicas. DESAFIOS METODOLÓGICOS: Cada etapa metodológica foi desenhada a fim de reduzir os erros e vieses atrelados aos desafios metodológicos. REGISTRO CAAE: 31670314.8.0000.5567. CONSIDERAÇÕES FINAIS: De grande potencial para futuras análises de dados, o EBANS intenta contribuir na geração de conhecimento para fomentar políticas e ações capazes de alterar o atual cenário de obesidade.

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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-A 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.

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Aquatic population responses to chemical exposure may be exacerbated by intraspecific competition pressures, being also shaped by habitat heterogeneity. Magnetic particles (MPs) have been recently proposed as promising phosphorus (P) adsorbents for lake restoration. This study focuses on assessing the effects of MPs on the abundance of the crustacean Daphnia magna under different levels of both intraspecific competition pressure and habitat heterogeneity. The experimental design consisted of two experiments (in homogeneous and heterogeneous habitats) done in glass jars with four concentrations of MPs: controls of 0g MPsL-1, and treatments of 1, 1.5 and 2g MPsL-1. In addition, competition treatments were established by using different population densities, and hence, no competition (C), low (L) and high (H) competition pressures were simulated. The experiments lasted for 7 days, with a 4-day pre-exposure period, in which competition was all allowed to take place, and a 3-day post-exposure period. Twenty-four hours after adding MPs, the MPs were removed by applying a magnetic separation technique. The results showed that competition pressures occurred and significantly reduced population abundances during the pre-exposure period. During the post-exposure period, the combined effects of competition and MPs were detected in both homogeneous (Ho-) and heterogeneous (He-) habitat experiments, showing a significantly drastic reduction in abundances. In fact, the lethal concentration for 50% of the population (LC50 -24h) was 0 and 0.16g MPsL-1 in the Ho- and He-experiments respectively, indicating that the addition and especially the removal of MPs cause extreme mortality. These results indicated that even though competition plays a role in shaping populations, its influence was down-weighted by the stronger pressures of MPs. In addition, as no significant differences between homogeneous and heterogeneous habitats were found, we may state that the refuge offered was not protective enough to avoid the effects of MPs. In conclusion, the removal of the MPs causes drastic effects on D. magna abundances despite the concentration of MPs, competition or habitat structure. Finally, considering the validated high efficiency of MPs for P removal, and in the context of a future whole-lake application, it is essential to restrict the use of MPs to the moments when D. magna is absent in the study site. Further research on the effects of MP removal on other organisms is required before implementing the addition of MPs as a restoration tool.

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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.

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ABSTRACT BACKGROUND Gastrointestinal symptoms seem to affect more women, due to hormonal and emotional issues, impacting the quality of life. The emotional state can affect the bowel functioning through a bidirectional communication system between the gut and the brain involving the neuroendocrine system. Altered bowel functioning and gastrointestinal symptoms can alter quality of life. OBJECTIVE The SIM study aimed to describe, characterize and quantify gastrointestinal symptoms reported by Brazilian women, their causes, feelings and impact. METHODS A structured electronic questionnaire was developed following qualitative phase for semantic formatting, and was administered to volunteer women in ten Brazilian cities. Descriptive and Bayesian statistics analyses were used. RESULTS From the 3029 respondent, 66% reported gastrointestinal symptoms. The most prevalent symptoms were gases (46%), abdominal distention and constipation (43%). The main causes were lifestyle and eating habits. Gastrointestinal symptoms affected quality of life in most women (62%), especially constipation (mood (89%), concentration (88%) and sexual life (79%)). Most common solutions were drinking water, teas, eating foods rich in fiber and probiotics. CONCLUSION Gastrointestinal symptoms are highly prevalent in Brazilian women and negatively impact different aspects of quality of life (mood, concentration and sexuality). The bowel is an important emotional catalyst that can modulate the psychologic behavior. Better understanding of the interaction between the gut and the brain should help in the management of gastrointestinal symptoms to improve women’s quality of life.

RESUMO CONTEXTO Sintomas gastrointestinais parecem afetar mais as mulheres, devido a problemas hormonais e emocionais, afetando a qualidade de vida. O estado emocional pode afetar o funcionamento do intestino por meio de um sistema de comunicação bidirecional entre o intestino e o cérebro que envolve o sistema neuroendócrino. Alterações da função intestinal e sintomas gastrointestinais podem afetar a qualidade de vida. OBJETIVO O estudo SIM teve como objetivo descrever, caracterizar e quantificar os sintomas gastrointestinais relatados por mulheres brasileiras, suas causas, sentimentos e impacto. MÉTODOS Questionário eletrônico estruturado foi desenvolvido após a fase qualitativa para formatação semântica, e foi administrado a mulheres voluntárias em 10 cidades brasileiras. Foram realizadas análises estatísticas descritivas e Bayesiana. RESULTADOS A partir dos 3029 respondentes, 66% relataram sintomas gastrointestinais. Os sintomas mais prevalentes foram gases (46%), distensão abdominal e constipação (43%). As principais causas relatadas foram estilo de vida e hábitos alimentares. Sintomas gastrointestinais afetaram a qualidade de vida da maioria das mulheres (62%), especialmente a constipação (humor (89%), concentração (88%) e vida sexual (79%)). As soluções mais comuns adotadas foram beber água, chás, comer alimentos ricos em fibras e probióticos. CONCLUSÃO Sintomas gastrointestinais são altamente prevalentes nas mulheres brasileiras e impactam negativamente diferentes aspectos da qualidade de vida (humor, concentração e sexualidade). O intestino é um catalisador emocional importante que pode modular o comportamento psicológico. Melhor compreensão da interação entre o intestino e o cérebro pode ajudar na gestão dos sintomas gastrointestinais para melhorar a qualidade de vida das mulheres.

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BACKGROUND: Gastrointestinal symptoms seem to affect more women, due to hormonal and emotional issues, impacting the quality of life. The emotional state can affect the bowel functioning through a bidirectional communication system between the gut and the brain involving the neuroendocrine system. Altered bowel functioning and gastrointestinal symptoms can alter quality of life. OBJECTIVE: The SIM study aimed to describe, characterize and quantify gastrointestinal symptoms reported by Brazilian women, their causes, feelings and impact. METHODS: A structured electronic questionnaire was developed following qualitative phase for semantic formatting, and was administered to volunteer women in ten Brazilian cities. Descriptive and Bayesian statistics analyses were used. RESULTS: From the 3029 respondent, 66% reported gastrointestinal symptoms. The most prevalent symptoms were gases (46%), abdominal distention and constipation (43%). The main causes were lifestyle and eating habits. Gastrointestinal symptoms affected quality of life in most women (62%), especially constipation (mood (89%), concentration (88%) and sexual life (79%)). Most common solutions were drinking water, teas, eating foods rich in fiber and probiotics. CONCLUSION: Gastrointestinal symptoms are highly prevalent in Brazilian women and negatively impact different aspects of quality of life (mood, concentration and sexuality). The bowel is an important emotional catalyst that can modulate the psychologic behavior. Better understanding of the interaction between the gut and the brain should help in the management of gastrointestinal symptoms to improve women's quality of life.

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