Phenotypic plasticity in sargassum forests may not counteract projected biomass losses along a broad latitudinal gradient

Phenotypic plasticity and local adaptation can adjust individual responses to environmental changes across species' ranges. Studies addressing the implications of such traits have been underrepresented in the marine environment. Sargassum cymosum represents an ideal model to test phenotypic plasticity, as populations along the southwestern Atlantic Ocean display a sharp decrease in abundance toward distributional range limits. We (1) characterized the macroecological environment of S. cymosum across a latitudinal gradient, (2) evaluated potential differences in ecophysiological adjustments (biomass, photosynthetic pigments, phenolic compounds, total soluble sugars and proteins, and carbon-nitrogen-CN-content), and (3) tested for differences in thermal tolerance based on time series analyses produced from the present to contrasting representative concentration pathways scenarios (RCP) of future climate changes. Our results showed distinct macroecological environments, corresponding to tropical and warm temperate conditions, driving biomass and ecophysiological adjustments of S. cymosum. Populations from the two environments displayed contrasting thermal tolerances, with tropical individuals better coping with thermal stress when compared to more temperate ones (lethal temperatures of 33 degrees C vs. 30 degrees C); yet both populations lose biomass in response to increasing thermal stress while increasing secondary metabolites (for example, carotenoids and phenolic compounds) and decrease chlorophyll's content, Fv/Fm, total soluble sugars concentration and CN ratio, owing to oxidative stress. Despite evidence for phenotypic plasticity, significant future losses might occur in both tropical and warm temperate populations, particularly under the no mitigation RCP scenario, also known as the business as usual (that is, 8.5). In this context, broad compliance with the Paris Agreement might counteract projected impacts of climate change, safeguarding Sargassum forests in the years to come.This study was supported by grants from Boticario Foundation, FAPESC-Foundation Support Research and Innovation in the State of Santa Catarina, Capes Higher Education Personnel Improvement Coordination, CNPq-National Council for Scientific and Technological Development, Petrobras Ambiental, REBENTOS-Habitat monitoring network coastal Benthic and ProspecMar-Islands Sustainable Prospecting in Ocean Islands: Biodiversity, Chemistry, Ecology and Biotechnology, Rede Coral Vivo, REDEALGAS, a Pew Marine Fellowship, the Foundation for Science and Technology (FCT) of Portugal via SFRH/BSAB/150485/2019, SFRH/BD/144878/2019, UID/Multi/04326/2019, PTDC/BIA-CBI/6515/2020 and the transitional norm DL57/2016/CP1361/CT0035. LPG received a doctorate scholarship (88882.438723/2019-01) from Capes. CFDG thanks CNPq grants PQ-309658/2016-0and306304/2019-8. PAH thanks CAPES-Senior Visitor, CAPESPrInt 310793/2018-01, CNPq-PVE 407365/2013-3, CNPq-Universal 426215/2016-8 and CNPq-PQ308537/2019-0. GK received a master's scholarship from CAPES.info:eu-repo/semantics/submittedVersio

Avaliação do equilíbrio corporal de pacientes com artrite reumatoide

Postural control, stability in voluntary movements in response to external disturbances and proprioception are basic elements for maintaining balance. People with Rheumatoid Arthritis (RA) have difficulty maintaining postural control, undermining the balance in the Activities of Daily Living (ADL's), making it an important risk factor for falls. The present study aimed to evaluate the body balance of individuals with RA, according to the level of disease activity. We evaluated 24 individuals with 54.66±9.52 years. All underwent a questionnaire identification and medical history, anthropometric measurements, blood sampling for analysis of C-Reactive Protein (CRP), determining the level of disease activity using the DAS-28 and equilibrium through tests: Berg Balance Scale (BBS) and TUG. Patients were divided into three groups: low, moderate and high disease activity. The results of equilibrium tests showed that, although the sample has presented low risk for falls, the group in high disease activity had higher frequency distribution (57.2%) in scores between 48-52 in the BBS compared to the moderate activity group, whose frequency distribution prevailed in the scores between 53 and 56 (92.3%-pControl postural, estabilidad en los movimientos voluntarios, reacción a las perturbaciones externas y propiocepción constituyen elementos básicos para la manutención del equilibrio. Personas con Artritis Reumatoidea (AR) tienen dificultad en mantener el control postural, perjudicando el equilibrio en las Actividades de Vida Diarias (AVD's), volviéndose un importante factor de riesgo de caídas. El presente estudio tuvo por objetivo evaluar el equilibrio corporal de individuos con AR, en función del nivel de actividad de la enfermedad. Fueron evaluados 24 individuos con 54,66±9,52 años. Todos fueron sometidos a la aplicación de cuestionario de identificación e historia clínica, evaluaciones antropométricas, colecta de muestra sanguínea para análisis de Proteína C-Reactiva (PCR), determinación del nivel de actividad de la enfermedad por medio del Disease Activity Score (DAS-28) y evaluación del equilibrio a través de los tests: Escala de Equilibrio de Berg (EEB) y Timed Up and Go (TUG). Los pacientes fueron divididos en tres grupos: baja, moderada y alta actividad de la enfermedad. Los resultados de los tests de equilibrio demostraron que, aunque la muestra haya presentado bajo riesgo de caídas, el grupo en alta actividad de la enfermedad presentó mayor distribución de frecuencia (57,2%) en los escores entre 48-52 en la EEB, en comparación con el grupo moderada actividad, cuya distribución de frecuencia predominó en los escores entre 53 y 56 (92,3%-pControle postural, estabilidade nos movimentos voluntários, reação às perturbações externas e propriocepção constituem elementos básicos para a manutenção do equilíbrio. Pessoas com Artrite Reumatoide (AR) têm dificuldade em manter o controle postural, prejudicando o equilíbrio nas Atividades de Vida Diárias (AVD's), tornando-se um importante fator de risco para quedas. O presente estudo teve por objetivo avaliar o equilíbrio corporal de indivíduos com AR, em função do nível de atividade da doença. Foram avaliados 24 indivíduos com 54,66±9,52 anos. Todos foram submetidos à aplicação de questionário de identificação e história clínica, avaliações antropométricas, coleta de amostra sanguínea para análise de Proteína C-Reativa (PCR), determinação do nível de atividade da doença por meio do Disease Activity Score (DAS-28) e avaliação do equilíbrio através dos testes: Escala de Equilíbrio de Berg (EEB) e Timed Up and Go (TUG). Os pacientes foram divididos em três grupos: baixa, moderada e alta atividade da doença. Os resultados dos testes de equilíbrio demonstraram que, embora a amostra tenha apresentado baixo risco para quedas, o grupo em alta atividade da doença apresentou maior distribuição de frequência (57,2%) nos escores entre 48-52 na EEB, em comparação ao grupo moderada atividade, cuja distribuição de frequência predominou nos escores entre 53 e 56 (92,3%-

Genome of Rhodnius prolixus, an insect vector of Chagas disease, reveals unique adaptations to hematophagy and parasite infection

Rhodnius prolixus not only has served as a model organism for the study of insect physiology, but also is a major vector of Chagas disease, an illness that affects approximately seven million people worldwide. We sequenced the genome of R. prolixus, generated assembled sequences covering 95% of the genome ( approximately 702 Mb), including 15,456 putative protein-coding genes, and completed comprehensive genomic analyses of this obligate blood-feeding insect. Although immune-deficiency (IMD)-mediated immune responses were observed, R. prolixus putatively lacks key components of the IMD pathway, suggesting a reorganization of the canonical immune signaling network. Although both Toll and IMD effectors controlled intestinal microbiota, neither affected Trypanosoma cruzi, the causal agent of Chagas disease, implying the existence of evasion or tolerance mechanisms. R. prolixus has experienced an extensive loss of selenoprotein genes, with its repertoire reduced to only two proteins, one of which is a selenocysteine-based glutathione peroxidase, the first found in insects. The genome contained actively transcribed, horizontally transferred genes from Wolbachia sp., which showed evidence of codon use evolution toward the insect use pattern. Comparative protein analyses revealed many lineage-specific expansions and putative gene absences in R. prolixus, including tandem expansions of genes related to chemoreception, feeding, and digestion that possibly contributed to the evolution of a blood-feeding lifestyle. The genome assembly and these associated analyses provide critical information on the physiology and evolution of this important vector species and should be instrumental for the development of innovative disease control methods

Molecular Evolution of Phosphoprotein Phosphatases in Drosophila

Phosphoprotein phosphatases (PPP), these ancient and important regulatory enzymes are present in all eukaryotic organisms. Based on the genome sequences of 12 Drosophila species we traced the evolution of the PPP catalytic subunits and noted a substantial expansion of the gene family. We concluded that the 18–22 PPP genes of Drosophilidae were generated from a core set of 8 indispensable phosphatases that are present in most of the insects. Retropositons followed by tandem gene duplications extended the phosphatase repertoire, and sporadic gene losses contributed to the species specific variations in the PPP complement. During the course of these studies we identified 5, up till now uncharacterized phosphatase retrogenes: PpY+, PpD5+, PpD6+, Pp4+, and Pp6+ which are found only in some ancient Drosophila. We demonstrated that all of these new PPP genes exhibit a distinct male specific expression. In addition to the changes in gene numbers, the intron-exon structure and the chromosomal localization of several PPP genes was also altered during evolution. The G−C content of the coding regions decreased when a gene moved into the heterochromatic region of chromosome Y. Thus the PPP enzymes exemplify the various types of dynamic rearrangements that accompany the molecular evolution of a gene family in Drosophilidae

How to make a sex chromosome

Sex chromosomes can evolve once recombination is halted between a homologous pair of chromosomes. Owing to detailed studies using key model systems, we have a nuanced understanding and a rich review literature of what happens to sex chromosomes once recombination is arrested. However, three broad questions remain unanswered. First, why do sex chromosomes stop recombining in the first place? Second, how is recombination halted? Finally, why does the spread of recombination suppression, and therefore the rate of sex chromosome divergence, vary so substantially across clades? In this review, we consider each of these three questions in turn to address fundamental questions in the field, summarize our current understanding, and highlight important areas for future work