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Anthropogenic changes to the environment challenge animal populations to adapt to new conditions and unique threats. While the study of adaptation has focused on genetic variation, epigenetic mechanisms may also be important. DNA methylation is sensitive to environmental stressors, such as parasites and pesticides, which may affect gene expression and phenotype. We studied the effects of an invasive ec toparasite, Philornis downsi, on DNA methylation of Galápagos mockingbirds (Mimus parvulus). We used the insecticide permethrin to manipulate P. downsi presence in nests of free-living mockingbirds and tested for effects of parasitism on nestling mockingbirds using epiGBS, a reduced-representation bisulfite sequencing (RRBS) approach. To distinguish the confounding effects of insecticide exposure, we con ducted a matching experiment exposing captive nestling zebra finches (Taeniopygia guttata) to permethrin. We used zebra finches because they were the closest model organism to mockingbirds that we could breed in controlled conditions. We identi fied a limited number of differentially methylated cytosines (DMCs) in parasitized versus nonparasitized mockingbirds, but the number was not more than expected by chance. In contrast, we saw clear effects of permethrin on methylation in captive zebra finches. DMCs in zebra finches paralleled documented effects of permethrin exposure on vertebrate cellular signaling and endocrine function. Our results from captive birds indicate a role for epigenetic processes in mediating sublethal nontar get effects of pyrethroid exposure in vertebrates. Environmental conditions in the field were more variable than the laboratory, which may have made effects of both parasitism and permethrin harder to detect in mockingbirds. RRBS approaches such as epiGBS may be a cost-effective way to characterize genome-wide methylation profiles. However, our results indicate that ecological epigenetic studies in natural populations should consider the number of cytosines interrogated and the depth of sequencing in order to have adequate power to detect small and variable effects

INTRODUCTION: Approximately 120,000 people live with Chagas disease in Europe, 43% of whom are living in Spain. Early diagnosis and treatment are critical to improve outcomes for those living with Chagas, and also for the prevention of ongoing transmission. The decision to be tested for Chagas is affected by a range of factors. Studies have highlighted the need to consider the wider social determinants of healthcare seeking behaviour related to Chagas. In Madrid, 44% of Bolivians undergo Chagas screening, which is a higher rate than other European regions, but studies concerning the factors which determine testing have not been performed. This study aimed to assess, for a first time, the factors associated with screening for Chagas among Bolivians living in Madrid trying to help in developing strategies and health recommendations. METHODS: This was a cross-sectional survey about knowledge of Chagas and practices of Bolivians living in Madrid, Spain. A structured questionnaire was administered to 376 participants regarding Chagas health-seeking behaviour. Determinants were assessed by multiple logistic regressions adjusted by sex. RESULTS: After adjusting for others variables and sex, the factors shown to be associated with Chagas screening were to have between 35 and 54 years of age; coming from a department with high prevalence of Chagas (OR 2.17 95% CI 0.99-4.76); received information about Chagas in Spain (OR 2.44 95% CI 1.32-4.51); and received any advice to do the test, especially if the advice came from a professional. CONCLUSIONS: Health authorities should coordinate and promote strategies addressed to diagnose and treat Chagas taking into account all factors associated with screening. Our study suggests that professional advice appears to be the cornerstone to encourage Bolivians to undergo Chagas screening in Madrid. It is time to change the burden of the decision of being screened from the patient to the doctor. Being diagnosed for Chagas needs to become an institutional strategy. This study was funding by the Insituto de Salud Carlos III (www.isciii.es)PI15CIII/00047 to TBH. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Reduced representation bisulfite sequencing is an emerging methodology for evolutionary and ecological genomics and epigenomics research because it provides a cost-effective, high-resolution tool for exploration and comparative analysis of DNA methylation and genetic variation. Here we describe how digestion of genomic plant DNA with restriction enzymes, subsequent bisulfite conversion of unmethylated cytosines, and final DNA sequencing allow for the examination of genome-wide genetic and epigenetic variation in plants without the need for a reference genome. We explain how the use of several combinations of barcoded adapters for the creation of highly multiplexed libraries allows the inclusion of up to 144 different samples/individuals in only one sequencing lane.

Anthropogenic activities have increased exposure to heavy metal pollution in previously uncontaminated ecosystems, threatening plant communities. Considering that phenotypic variation underlies rapid adjustment to challenging environmental conditions in natural populations, the study of variation in traits related to plant response to heavy metal stress provides valuable insight into the likelihood of a population’s survival. This paper investigates patterns of intraspecific phenotypic variation for heavy metal accumulation and tolerance in bryophytes, one of the most resilient and relatively understudied plant taxa. We examined two moss species with contrasting affinities for heavy metals: the heavy metal specialist Scopelophila cataractae, and the facultative metallophyte Ceratodon purpureus. We sampled four populations of S. cataractae in close microhabitats with different contamination levels of Cd and Cu, one population of C. purpureus in an urban area, and separate lab-maintained male and female isolates from one population of C. purpureus growing in axenic conditions. After clonally propagating all populations under control, Cd and Cu treatments, we measured plant fitness, oxidative damage, and Cd and Cu accumulation. Scopelophila cataractae isolates from microhabitats with higher levels of metals in the field (Sc2, Sc3) were more tolerant than those collected in less contaminated microhabitats (Sc1, Sc4). Sc2 and Sc3 accumulated significantly less Cu in the leaves compared to the stem which could limit damage to their main photosynthetic organs and contribute to the observed differences in Cu tolerance. In contrast C. purpureus showed intraspecific differences in tolerance to Cd and Cu, but not in accumulation. These differences arose among isolates that had never been exposed to heavy metals before. We also report the first evidence for sexual dimorphism for Cd tolerance in this species, with females being more tolerant than males. Altogether, our results provide novel insights into the mechanisms used by bryophytes to deal with heavy metal stress, as well as the first evidence for metal-dependent, sex-specific differences in heavy metal tolerance in bryophytes.

In this study, we used amplified fragment length polymorphism analysis to investigate the genetic structure of the terrestrial moss Pseudoscleropodium purum (Hedw.) M. Fleish. naturally exposed to different levels of atmospheric deposition of heavy metals. We also determined the heavy metal concentrations in samples of this moss to evaluate whether there was a relationship between atmospheric pollution and population genetic diversity. A low level of genetic diversity and a limited gene flow among populations were observed which is in accordance to the prevalence of asexual reproduction in this species. In addition, no significant correlation was found between metal content and gene diversity in P. purum, probably because of the common history of the sampled populations and/or to the lack of a drastic reduction of the size of the population; nonetheless, a clear genetic structure was evident in relation to the existing pollution gradient. Thus, based on the results of the principal coordinate analysis and Bayesian analysis of the genotypes, the mixed structure of the second most polluted population would suggest an ongoing differentiation of metal-tolerant genotypes in the most polluted sites of the sampling area.

Background Chagas disease has crossed South America’s borders and in recent years has spread to regions that were not previously affected. Early diagnosis and treatment of Chagas disease improves the clinical prognosis and prevents vertical transmission. Taking into account the lack of evidence of how primary care services manage Chagas disease in a non-endemic country, this study assessed Chagas disease knowledge, attitudes and practices among primary health care professionals. Methods and principal findings Between 2017 and 2019, eight focus groups were formed with 41 family physicians and 40 nurses from healthcare centers in Madrid, Spain, and 70 field notes were collected during non-participant observation. The family physicians and nurses showed a lack of general knowledge about Chagas disease, and they did not identify the country of origin to request the blood test. The family physicians and nurses thought that the population did not talk broadly about Chagas disease because of the stigma or shame. The role of nurses was more focused on vaccination status and chronic disease follow-up, and family physicians assumed a facilitating role to send patients to different hospital facilities. Communication between primary care professionals and the hospital is a barrier frequently experienced by family physicians. Conclusions The diagnosis of CD in non-endemic countries continues being an important challenge for health systems. The results obtained with the study of the knowledge, attitudes and practices at primary care through a qualitative approach allows to obtain evidence that could help to develop strategies for the screening of CD in a protocolized way in order to avoid that the diagnosis depends exclusively on the request of the patient., Author summary Spain is the country with the highest burden of Chagas disease, with an estimated 52,000 cases, 81% of which are reported. Nevertheless, recent publications have shown that only 44% of the Bolivian population living in Madrid had a screening test performed (prevalence = 27.7%). This neglected tropical disease is transmitted through the bite of a kissing bug in endemic regions, while mother-to-child transmission, as well as blood transfusion and organ transplant transmissions occur in endemic and non-endemic countries. Without treatment, Chagas disease could cause severe cardiac and/or gastrointestinal symptoms, and ultimately death. Early diagnosis and treatment of Chagas disease improves the clinical prognosis, prevents vertical transmission and it could also prevent blood transfusion and organ transplant transmissions. Our study is the first study in Spain to use qualitative methods to explore the knowledge, attitudes and practices of primary care professionals about Chagas disease. The results show that is necessary to develop strategies in a protocolized way in order to avoid that the diagnosis depends exclusively on the request of the patient. Our findings have important public health and policy implications, offering different strategies in primary care which could facilitate the early diagnosis of Chagas disease.

BACKGROUND: It is estimated that around 52,000 people live with Chagas in Spain, but only 10% have been diagnosed. Migrants from Bolivia bear the burden of Chagas infection in Spain. However, little is known about their current management of Chagas diagnosis and treatment patterns. This study aimed to assess the Chagas related disease perception and health behaviour of Bolivians living in Madrid. METHODS AND PRINCIPAL FINDINGS: For a first time, a cross-sectional survey about Chagas' knowledges and practices was carried out in Madrid, Spain. A total of 376 Bolivians were interviewed about their Chagas health-seeking behaviour. Differences between men and women were assessed Most of Bolivians living in Madrid have access to the public health services. 44% of Bolivians included in the survey had a Chagas screening test done. However, while women did their test for Chagas mostly at hospital (59.2%), men also used the community campaigns (17.5%) and blood banks (14.3%). The prevalence reported among Bolivians tested was 27.7%. Unfortunately, more than half of those reporting a positive test for Chagas did not begin or completed treatment. Only 45.7% of positives reported having had their children tested for Chagas. CONCLUSIONS: Despite the increase in the number of Chagas diagnoses done in Madrid, the number of Bolivians who tested positive and then started or completed treatment remains very low. The fact that most Bolivians' access to the health system is through the primary healthcare services should be considered for improving management of cases and follow-up of treatment adherence. Local and national protocol establishing guidelines for the screening and treatment of Chagas disease would help improving case detection and management at all levels of the healthcare system. This study was funding by the Insituto de Salud Carlos III (www.isciii.es) PI15CIII/00047 to TBH. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Sí