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Earth harbours an extraordinary plant phenotypic diversity1 that is at risk from ongoing global changes2,3. However, it remains unknown how increasing aridity and livestock grazing pressure-two major drivers of global change4-6-shape the trait covariation that underlies plant phenotypic diversity1,7. Here we assessed how covariation among 20 chemical and morphological traits responds to aridity and grazing pressure within global drylands. Our analysis involved 133,769 trait measurements spanning 1,347 observations of 301 perennial plant species surveyed across 326 plots from 6 continents. Crossing an aridity threshold of approximately 0.7 (close to the transition between semi-arid and arid zones) led to an unexpected 88% increase in trait diversity. This threshold appeared in the presence of grazers, and moved toward lower aridity levels with increasing grazing pressure. Moreover, 57% of observed trait diversity occurred only in the most arid and grazed drylands, highlighting the phenotypic uniqueness of these extreme environments. Our work indicates that drylands act as a global reservoir of plant phenotypic diversity and challenge the pervasive view that harsh environmental conditions reduce plant trait diversity8-10. They also highlight that many alternative strategies may enable plants to cope with increases in environmental stress induced by climate change and land-use intensification.
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Biodiversidad , Clima Desértico , Herbivoria , Fenotipo , Plantas , Plantas/clasificación , Plantas/anatomía & histología , Animales , Ganado , Cambio ClimáticoRESUMEN
A doença de Madelung é caracterizada pelo acúmulo simétrico e difuso de tecido adiposo com crescimento tumoral lento e progressivo. Neste relato de caso, um paciente portador dessa síndrome foi atendido no Hospital das Clínicas, em Recife, PE, com o objetivo de realizar uma redução do conteúdo lipomatoso através de lipectomia. O paciente apresentava volumosas massas de tecido adiposo elástico ao redor do pescoço e região supraclavicular e a proposta terapêutica consistiu em uma cirurgia em dois tempos, com lipoaspiração e lipectomia cervical anterior, seguida de lipoaspiração e lipectomia cervical posterior. Antes da cirurgia, foi solicitado um parecer cardiológico, que indicou um risco intermediário, mas não contraindicou o procedimento. Após 4 dias da cirurgia, o paciente apresentou equimoses e edema periférico na ferida operatória cervical, porém estava assintomático. As técnicas de lipectomia e lipoaspiração são consideradas os métodos de tratamento mais eficazes para a doença de Madelung. No entanto, a escolha da cirurgia deve ser baseada em uma avaliação abrangente da gravidade da doença, localização da massa e expectativas do paciente, uma vez que ambas as técnicas possuem vantagens e desvantagens.
Madelung's disease is characterized by the symmetric and diffuse accumulation of adipose tissue with slow and progressive tumor growth. In this case report, a patient with this syndrome was treated at Hospital das Clínicas, in Recife, PE, to reduce the lipomatous content through a lipectomy. The patient presented large masses of elastic adipose tissue around the neck and supraclavicular region and the therapeutic proposal consisted of a two-stage surgery, with liposuction and anterior cervical lipectomy, followed by liposuction and posterior cervical lipectomy. Before surgery, a cardiological opinion was requested, which indicated an intermediate risk but did not contraindicate the procedure. Four days after surgery, the patient presented bruises and peripheral edema in the cervical surgical wound but was asymptomatic. Lipectomy and liposuction techniques are considered the most effective treatment methods for Madelung disease. However, the choice of surgery should be based on a comprehensive assessment of the severity of the disease, location of the mass, and patient expectations, as both techniques have advantages and disadvantages.
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Spiders are a diverse order of chelicerates that diverged from other arthropods over 500 million years ago. Research on spider embryogenesis, particularly studies using the common house spider Parasteatoda tepidariorum, has made important contributions to understanding the evolution of animal development, including axis formation, segmentation, and patterning. However, we lack knowledge about the cells that build spider embryos, their gene expression profiles and fate. Single-cell transcriptomic analyses have been revolutionary in describing these complex landscapes of cellular genetics in a range of animals. Therefore, we carried out single-cell RNA sequencing of P. tepidariorum embryos at stages 7, 8 and 9, which encompass the establishment and patterning of the body plan, and initial differentiation of many tissues and organs. We identified 20 cell clusters, from 18.5 k cells, which were marked by many developmental toolkit genes, as well as a plethora of genes not previously investigated. We found differences in the cell cycle transcriptional signatures, suggestive of different proliferation dynamics, which related to distinctions between endodermal and some mesodermal clusters, compared with ectodermal clusters. We identified many Hox genes as markers of cell clusters, and Hox gene ohnologs were often present in different clusters. This provided additional evidence of sub- and/or neo-functionalisation of these important developmental genes after the whole genome duplication in an arachnopulmonate ancestor (spiders, scorpions, and related orders). We also examined the spatial expression of marker genes for each cluster to generate a comprehensive cell atlas of these embryonic stages. This revealed new insights into the cellular basis and genetic regulation of head patterning, hematopoiesis, limb development, gut development, and posterior segmentation. This atlas will serve as a platform for future analysis of spider cell specification and fate, and studying the evolution of these processes among animals at cellular resolution.
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Many annelids can regenerate missing body parts or reproduce asexually, generating all cell types in adult stages. However, the putative adult stem cell populations involved in these processes, and the diversity of cell types generated by them, are still unknown. To address this, we recover 75,218 single cell transcriptomes of the highly regenerative and asexually-reproducing annelid Pristina leidyi. Our results uncover a rich cell type diversity including annelid specific types as well as novel types. Moreover, we characterise transcription factors and gene networks that are expressed specifically in these populations. Finally, we uncover a broadly abundant cluster of putative stem cells with a pluripotent signature. This population expresses well-known stem cell markers such as vasa, piwi and nanos homologues, but also shows heterogeneous expression of differentiated cell markers and their transcription factors. We find conserved expression of pluripotency regulators, including multiple chromatin remodelling and epigenetic factors, in piwi+ cells. Finally, lineage reconstruction analyses reveal computational differentiation trajectories from piwi+ cells to diverse adult types. Our data reveal the cell type diversity of adult annelids by single cell transcriptomics and suggest that a piwi+ cell population with a pluripotent stem cell signature is associated with adult cell type differentiation.
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Células Madre Adultas , Oligoquetos , Células Madre Pluripotentes , Animales , Diferenciación Celular/genética , Factores de Transcripción/genéticaRESUMEN
This overview initially describes insect immune reactions and then brings together present knowledge of the interactions of vector insects with their invading parasites and pathogens. It is a way of introducing this Special Issue with subsequent papers presenting the latest details of these interactions in each particular group of vectors. Hopefully, this paper will fill a void in the literature since brief descriptions of vector immunity have now been brought together in one publication and could form a starting point for those interested and new to this important area. Descriptions are given on the immune reactions of mosquitoes, blackflies, sandflies, tsetse flies, lice, fleas and triatomine bugs. Cellular and humoral defences are described separately but emphasis is made on the co-operation of these processes in the completed immune response. The paper also emphasises the need for great care in extracting haemocytes for subsequent study as appreciation of their fragile nature is often overlooked with the non-sterile media, smearing techniques and excessive centrifugation sometimes used. The potential vital role of eicosanoids in the instigation of many of the immune reactions described is also discussed. Finally, the priming of the immune system, mainly in mosquitoes, is considered and one possible mechanism is presented.
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Typical two-cysteine peroxiredoxins (2-Cys-PRXs) are H2O2-metabolizing enzymes whose activity relies on two cysteine residues. Protists of the family Trypanosomatidae invariably express one cytosolic 2-Cys-PRX (cPRX1). However, the Leishmaniinae sub-family features an additional isoform (cPRX2), almost identical to cPRX1, except for the lack of an elongated C-terminus with a Tyr-Phe (YF) motif. Previously, cytosolic PRXs were considered vital components of the trypanosomatid antioxidant machinery. Here, we shed new light on the properties, functions and relevance of cPRXs from the human pathogen Leishmania infantum. We show first that LicPRX1 is sensitive to inactivation by hyperoxidation, mirroring other YF-containing PRXs participating in redox signaling. Using genetic fusion constructs with roGFP2, we establish that LicPRX1 and LicPRX2 can act as sensors for H2O2 and oxidize protein thiols with implications for signal transduction. Third, we show that while disrupting the LicPRX-encoding genes increases susceptibility of L. infantum promastigotes to external H2O2in vitro, both enzymes are dispensable for the parasites to endure the macrophage respiratory burst, differentiate into amastigotes and initiate in vivo infections. This study introduces a novel perspective on the functions of trypanosomatid cPRXs, exposing their dual roles as both peroxidases and redox sensors. Furthermore, the discovery that Leishmania can adapt to the absence of both enzymes has significant implications for our understanding of Leishmania infections and their treatment. Importantly, it questions the conventional notion that the oxidative response of macrophages during phagocytosis is a major barrier to infection and the suitability of cPRXs as drug targets for leishmaniasis.
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Leishmania , Leishmaniasis , Parásitos , Animales , Humanos , Peroxirredoxinas/metabolismo , Cisteína/metabolismo , Peróxido de Hidrógeno/metabolismo , Parásitos/metabolismo , Oxidación-ReducciónRESUMEN
Herpes simplex virus type 2 (HSV-2) is the most common agent of sexually transmitted infections around the world. Currently, no vaccine is available, and acyclovir is the reference compound in treatment HSV-2 infections. However, the emergence of resistant strains has reduced the efficacy in treatment. Several studies have shown marine seaweed biological activities, but there are no studies yet about the activity anti-HSV-2 of two its secundary metabolites, atomaric acid (1) and marine dolastane (2), isolated from Stypopodium zonale and Canistrocarpus cervicornis respectively. Therefore, we evaluated the anti-HSV-2 activity of compounds 1 and 2. Both compounds showed anti-HSV-2 activity with low cytotoxicity and compound 1 inactivated 90% of the viral particles at 50 µM. Both compounds inhibited the penetration and results in silico indicated the compound 1 as possible therapy alternative anti -HSV-2.
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Pollination is a crucial ecosystem service for maintaining plant communities and food production. 75% of the main crops depend on or benefit from pollination services provided by animal pollinators. However, when these services are insufficient and/or inefficient, crops experience pollen limitation with, often, lower associated yield, which may translate into economic losses. We constructed a global dataset that gathers studies with pollination experiments, aiming to provide pollen limitation values of animal-pollinated crops worldwide. Pollination experiments included hand pollen supplementation treatments, where plants were subjected to pollen supplementation of outcross pollen, and natural pollination treatments. The PolLimCrop dataset comprises 294 studies and 1169 unique pollen supplementation experiments with values of pollen limitation for 108 crops, spanning 50 years and 62 countries.
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Productos Agrícolas , Polinización , Ecosistema , Flores , PolenRESUMEN
Planarian cell dissociation methods using enzymatic approaches are well established and have been widely used in the field. However, their use in transcriptomics and especially single-cell transcriptomics raises concerns as cells are dissociated alive, and this induces cellular stress responses. Here we describe a protocol for planarian cell dissociation using ACME, a dissociation-fixation approach based on acetic acid and methanol. ACME-dissociated cells are fixed, can be cryopreserved, and are amenable to modern methods of single-cell transcriptomics.
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Planarias , Animales , Citometría de Flujo/métodos , Planarias/fisiología , Separación Celular , Agua DulceRESUMEN
Annelids are a broadly distributed, highly diverse, economically and environmentally important group of animals. Most species can regenerate missing body parts, and many are able to reproduce asexually. Therefore, many annelids can generate all adult cell types in adult stages. However, the putative adult stem cell populations involved in these processes, as well as the diversity of adult cell types generated by them, are still unknown. Here, we recover 75,218 single cell transcriptomes of Pristina leidyi, a highly regenerative and asexually-reproducing freshwater annelid. We characterise all major annelid adult cell types, and validate many of our observations by HCR in situ hybridisation. Our results uncover complex patterns of regionally expressed genes in the annelid gut, as well as neuronal, muscle and epidermal specific genes. We also characterise annelid-specific cell types such as the chaetal sacs and globin+ cells, and novel cell types of enigmatic affinity, including a vigilin+ cell type, a lumbrokinase+ cell type, and a diverse set of metabolic cells. Moreover, we characterise transcription factors and gene networks that are expressed specifically in these populations. Finally, we uncover a broadly abundant cluster of putative stem cells with a pluripotent signature. This population expresses well-known stem cell markers such as vasa, piwi and nanos homologues, but also shows heterogeneous expression of differentiated cell markers and their transcription factors. In these piwi+ cells, we also find conserved expression of pluripotency regulators, including multiple chromatin remodelling and epigenetic factors. Finally, lineage reconstruction analyses reveal the existence of differentiation trajectories from piwi+ cells to diverse adult types. Our data reveal the cell type diversity of adult annelids for the first time and serve as a resource for studying annelid cell types and their evolution. On the other hand, our characterisation of a piwi+ cell population with a pluripotent stem cell signature will serve as a platform for the study of annelid stem cells and their role in regeneration.
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Enhanced drought, more frequent rainfall events and increased inter-annual variability of precipitation are the main trends of climate expected for the Mediterranean. Drought is one of the most important stressors for plants and significantly impacts plant communities causing changes in plant composition and species dominance. Through an experiment under controlled conditions, we assessed the response of Mediterranean species from different functional groups (annual grass, annual forb, annual legume, and perennial shrub) to moderate and severe water deficit. Changes in plant traits (leaf dry matter), biomass and physiology (water status, photosynthesis, pigments, and carbohydrate) were evaluated. The studied species differed in their response to water deficit. Ornithopus compressus, the legume, showed the strongest response, particularly under severe conditions, decreasing leaf relative water content (RWC), pigments and carbohydrates. The grass, Agrostis pourreti and the forb, Tolpis barbata, maintained RWC, indicating a higher ability to cope with water deficit. Finally, the shrub, Cistus salviifolius, had the lowest response to stress, showing a higher ability to cope with water deficit. Despite different responses, plant biomass was negatively affected by severe water deficit in all species. These data provide background for predicting plant diversity and species composition of Mediterranean grasslands and Montado under climate change conditions.
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Polyploidy has important ecological effects, including ploidy-mediated effects on morphology, breeding system and ecological tolerances. However, there is still little comprehensive research available to test its adaptive significance and its role in driving distributional patterns. This work aimed to assess the contribution of genome duplications to ecological divergence using an experimental approach with the diploid-tetraploid Jasione maritima polyploid complex. We explored if individuals with different ploidy differ in their tolerance to water deficit and if this may contribute to explaining the distribution patterns along a latitudinal gradient in the northwest Iberian Peninsula. For that, we used three cytogenetic entities: diploids and established tetraploids collected in natural populations along a latitudinal gradient, and neotetraploids synthesized from diploid populations after treatments with colchicine. Thirty plants from each of the nine populations were grown under controlled conditions with half randomly assigned to the water deficit treatment, and half used as control. We determined experimental plants' response by measuring fitness-related parameters, such as above and belowground biomass, plant water status, photosynthetic efficiency and pigments, membrane stability, antioxidant capacity and sugars content. Our data shows that biomass, chlorophyll content, photochemical quenching (qP) and non-photochemical quenching (NPQ) in neotetraploids and established tetraploids were significantly higher than in diploids and that these differences could be attributed to genome duplications. In response to the water deficit, diploids seem to use a strategy of avoidance, whereas tetraploids seem to employ the strategy of tolerance to overcome water deficit stress, which appears equally efficient. Additionally, we did not observe a response pattern along the latitudinal gradient of the distributional range of the J. maritima complex. The results indicate that the response to water deficit is population dependent. Further studies are necessary to understand the role of ploidy in explaining the distribution patterns of the J. maritima complex.
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Sporothrix brasiliensis with low susceptibility isolates were described from the Brazilian zoonotic sporotrichosis hyperendemics. The aim of this work was to evaluate distinct fractions of Ocotea pulchella, Ocotea notata, Myrciaria floribunda, and Hypericum brasiliense plant extracts against itraconazole-sensitive and low susceptibility S. brasiliensis isolates. Crude extracts were tested against clinical isolates and the ATCC MYA4823 to determine the minimum inhibitory concentrations (MICs) and fungicidal or fungistatic activities (MFC). A high MICs and MFCs amplitude (1 - > 128 µg/mL) were obtained for seven extracts. The highest antimicrobial activities against sensitive S. brasiliensis were displayed by the ethyl acetate extracts of O. notata (MIC = 2-128 µg/mL) and M. floribunda (MIC = 1-8 µg/mL). A fungicidal effect was observed for all fraction extracts. Ocotea spp. and M. floribunda ethyl acetate extracts provide promising profiles against itraconazole-sensitive or low susceptibility S. brasiliensis. Future studies will determine if these extracts can contribute as alternative therapies to this neglected zoonosis.
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Fungicidas Industriales , Ocotea , Sporothrix , Esporotricosis , Itraconazol/farmacología , Antifúngicos/farmacología , Esporotricosis/microbiología , Fungicidas Industriales/farmacología , Pruebas de Sensibilidad MicrobianaRESUMEN
BACKGROUND: Since the emergence of HSV resistant strains, new antiviral agents have emerged and still are urgently needed, especially those with alternative targets. OBJECTIVE: In this work, we evaluated new quinolone derivatives as anti-HSV. METHODS: For this study, cells were infected and treated with different components to evaluate the profile of HSV replication in vitro. In addition, studies were performed to determine the pharmacokinetic toxicity and profile of the compound. RESULTS: Indeed the EC50 values of these promising molecules ranged between 8 µM and 32 µM. We have also showed that all compounds inhibited the expression of ICP27 viral proteins, which gives new insights in the search for new target for antiherpetic therapy. Chlorine in positions C6 and phosphonate in position C1 have shown to be important for viral inhibition. The chloroquinolone carboxamide derivatives fulfilled "Lipinsky Rule of Five" for good oral bioavailability and showed higher intestinal absorption and blood brain barrier penetration, as well as lower toxicity profile. CONCLUSION: Although the inhibition activities of chloroquinolone carboxamide derivatives were lower than acyclovir, they showed different modes of action in comparison to the drugs currently available. These findings encourage us to continue pre-clinical studies for the development of new anti-HSV-1 agents.
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Herpesvirus Humano 1 , Replicación Viral , Herpesvirus Humano 2/fisiología , Aciclovir/farmacología , Aciclovir/uso terapéutico , Antivirales/farmacología , Antivirales/uso terapéutico , Herpesvirus Humano 1/fisiologíaRESUMEN
Despite intramuscular vaccines saving millions of lives, constant devastating waves of SARS-CoV-2 infections continue. The elimination of COVID-19 is challenging, but necessary in order to avoid millions more people who would suffer from long COVID if we fail. Our paper describes rapidly advancing and innovative therapeutic strategies for the early stage of infection with COVID-19 so that tolerating continuing cycles of infection should be unnecessary in the future. These therapies include new vaccines with broader specificities, nasal therapies and antiviral drugs some targeting COVID-19 at the first stage of infection and preventing the virus entering the body in the first place. Our article describes the advantages and disadvantages of each of these therapeutic options which in various combinations could eventually prevent renewed waves of infection. Finally, important consideration is given to political, social and economic barriers that since 2020 hindered vaccine application and are likely to interfere again with any COVID-19 endgame.
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COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Síndrome Post Agudo de COVID-19 , SARS-CoV-2 , Antivirales/uso terapéuticoRESUMEN
Grazing represents the most extensive use of land worldwide. Yet its impacts on ecosystem services remain uncertain because pervasive interactions between grazing pressure, climate, soil properties, and biodiversity may occur but have never been addressed simultaneously. Using a standardized survey at 98 sites across six continents, we show that interactions between grazing pressure, climate, soil, and biodiversity are critical to explain the delivery of fundamental ecosystem services across drylands worldwide. Increasing grazing pressure reduced ecosystem service delivery in warmer and species-poor drylands, whereas positive effects of grazing were observed in colder and species-rich areas. Considering interactions between grazing and local abiotic and biotic factors is key for understanding the fate of dryland ecosystems under climate change and increasing human pressure.
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Biodiversidad , Herbivoria , Ganado , Cambio Climático , SueloRESUMEN
Single-cell transcriptomics has revolutionised biology allowing the quantification of gene expression in individual cells. Since each single cell contains cell type specific mRNAs, these techniques enable the classification of cell identities. Therefore, single cell methods have been used to explore the repertoire of cell types (the single cell atlas) of different organisms, including freshwater planarians. Nowadays, planarians are one of the most prominent animal models in single cell biology. They have been studied at the single cell level for over a decade using most of the available single cell methodological approaches. These include plate-based methods, such as qPCR, nanodroplet methods and in situ barcoding methods. Because of these studies, we now have a very good picture of planarian cell types and their differentiation trajectories. Planarian regenerative properties and other characteristics, such as their developmental plasticity and their capacity to reproduce asexually, ensure that another decade of single cell biology in planarians is yet to come. Here, we review these characteristics, the new biological insights that have been obtained by single-cell transcriptomics and outline the perspectives for the future.
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Planarias , Células Madre Pluripotentes , Animales , Planarias/genética , Planarias/metabolismo , Transcriptoma , Diferenciación Celular , ARN Mensajero/metabolismo , Regeneración/genéticaRESUMEN
Introdução: A pandemia por SARS-CoV-2 destacou o trabalho dos fisioterapeutas, sobretudo em relação à assistência aos pacientes acometidos pela Síndrome Respiratória Aguda Grave, também conhecida como Coronavirus Disease 2019 (COVID-19). Objetivo: O presente estudo visou destacar a importância do trabalho dos fisioterapeutas no cuidado aos pacientes com COVID-19. Métodos: Trata-se de uma revisão de literatura que utilizou as bases de dados da Biblioteca Virtual em Saúde (BVS), Portal de Periódicos da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) e do Medline/Pubmed e seguintes descritores: COVID-19 and Respiratory Syndrome and Physical therapy. Os critérios de inclusão foram os estudos publicados de dezembro de 2019 a setembro de 2020, nos idiomas inglês, espanhol e francês, disponíveis online, na íntegra e com abordagem plena do conteúdo. Resultados: Foram encontrados 160 artigos, dos quais 32 foram selecionados a partir dos critérios de inclusão. Conclusão: Os estudos relataram melhora clínica e funcional a partir das intervenções fisioterapêuticas aplicadas aos pacientes, sendo as medidas com maior impacto positivo na mobilização precoce, aspirações de secreções, monitoramento da ventilação mecânica e reabilitação. É de suma importância o fisioterapeuta estar inserido na equipe multidisciplinar que compõe o ambiente hospitalar.
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This study aimed at identifying the perceptions of Brazilian postgraduate students from all over the country on the impacts of the COVID-19 pandemic on their academic trajectories. Data from 5985 postgraduate students were collected in the end of 2020, through a 37-item questionnaire, including multiple-choice questions, through Google Forms. The questions were divided into blocks with different proposals: personal profile, academic profile, issues related to COVID-19 infection, and issues related to mental health. Our analysis showed that 51.43% were master's degree students; 43.02% were doctorate and 5.55% were specialization students, mostly attending Biological, Health, and Human Sciences post-graduation courses (18.13%, 17.91%, and 17.38%, respectively) of different Brazilian educational institutions, including public (e.g., UFRJ) and private (e.g., PUC) federal universities as well as research institutions (e.g., Fiocruz) from all five regions of Brazil (north, south, southeast, northeast, and center Midwest). Most of them were academically impacted by the COVID-19 pandemic, which also involved psychological aspects such as high levels of anxiety and depression. The results showed readjustments of research projects, and academic activities, which in some particular research fields led to the successful completion through the remote activities. However, efforts are still needed by graduate programs in order to allow greater flexibility in academic activities to fulfill all previous planning and chronograms, in addition to implementing ongoing projects to support students' mental health.