Adaptação de Cladóceros a ambientes heterogéneos contaminados por metais

Doutoramento em BiologiaNo presente trabalho o cladócero Daphnia longispina foi utilizado como organismo modelo para a avaliação dos efeitos ecológicos da adaptação a ambientes contaminados por metais. Foram amostradas populações naturais de D. longispina num local sujeito à contaminação por metais e num local próximo, de referência, ambos localizados no sistema aquático na área envolvente à mina abandonada de São Domingos. Várias linhagens clonais de ambas as populações foram mantidas em laboratório, sob condições controladas, para a execução dos testes. Um dos testes realizados permitiu estudar e quantificar as diferenças na tolerância letal entre as linhagens clonadas de ambas as populações e também avaliar os custos associados. Utilizando vinte linhagens clonais de D. longispina das duas populações verificou-se que apenas clones sensíveis ao cobre estavam presentes na população de referência e clones resistentes ao cobre estavam presentes na população do local contaminado. Os custos associados à tolerância foram ilustrados pela determinação de taxas alimentares mais baixas para a população tolerante quando comparadas com as da população de referência. Outro dos testes realizados permitiu comparar as respostas de clones de populações de ambos os locais – contaminado e referência – à exposição a concentrações sub-letais do metal cobre. A tolerância evidenciada anteriormente ao nível letal foi confirmada ao nível sub-letal, com o clone proveniente da população do local contaminado evidenciando uma maior tolerância ao cobre quando comparado com os restantes clones, para todos os parâmetros analisados (taxas alimentares, consumo de oxigénio, crescimento e reprodução). Os efeitos da aclimatação ao cobre ao longo de várias gerações foram também avaliados num clone de D. longispina. Os resultados evidenciaram a existência de uma adaptação fisiológica ao cobre ao longo das várias gerações que, no entanto, apenas aumentou marginalmente a tolerância a níveis de cobre letais. Para além disso, observou-se também uma grande variação nas respostas do clone de D. longispina estudado, não só entre concentrações de cobre mas também entre gerações. Os resultados obtidos nos vários estudos realizados com linhagens clonais de ambas as populações de D. longispina reforçam a importância de integrar a temática do desenvolvimento de tolerância à poluição aquando da avaliação dos riscos ambientais e ecológicos de compostos químicos, como os metais, no meio ambiente.In the present study the cladoceran Daphnia longispina was used as a model organism to test the ecological side effects of adaptation to metal contaminated environments. D. longispina natural populations were sampled from a metal contaminated reservoir and from a nearby clean water reservoir, both belonging to the aquatic system surrounding the abandoned São Domingos cupric mine. Clonal lineages were established and maintained in the laboratory by means of asexual reproduction and were used for tests. The comparison of broad sense heritabilities and genetic correlations using up to twenty distinct clonal D. longispina lineages randomly obtained from the metal contaminated reservoir and the reference reservoir showed that only sensitive and resistant lineages to Cu were present in the reference and contaminated site, respectively. For Zn, however, both populations had a similar distribution pattern of sensitivities. Fitness costs of tolerance were illustrated by lower feeding rates of the tolerant population compared to the reference one. Another study assessing life-history responses to sublethal copper contamination in four D. longispina clones, two from a reference site and the other two from a historically copper-exposed site showed that tolerance manifested by D. longispina clones at lethal copper levels was also evident at sublethal concentrations, with the tolerant clone from impacted population showing higher tolerance to copper for all the parameters (feeding, oxygen consumption, growth and reproduction) compared to the rest of clones. The multigenerational effects of acclimation to copper were also evaluated by exposing a single clone of D. longispina originated from the reference population to copper over three consecutive generations. Results from the evaluation of its life-history performance illustrate that physiological adaptation to copper across several generations only increased marginally acute tolerance to copper. Besides that, a high variation in life-history traits was observed not only between copper treatments, but also among generations. For instance, generation had a significantly influence on the observed pattern of age at first reproduction and interact with copper in the observed variation of time and clutch size at first reproduction. Overall, the importance of studying long-term adaptation to metals in natural populations is highlighted in this study as the acquisition of genetically inherited tolerance could have associated ecological costs. The obtained results reinforce the need to integrate these issues when assessing risks posed by chemicals to the environment.FCT/FSE - SFRH/BD/12324/200

Committed to restoring tropical forests: an overview of Brazil’s and Indonesia’s restoration targets and policies

The restoration of tropical forests has become a popular nature-based solution for climate change mitigation, protection of biodiversity, and improving the livelihoods of local populations. The Bonn Challenge and the UN Decade on Ecosystem Restoration underscore the international momentum of the restoration movement, with many countries committing to restore millions of hectares of deforested and degraded land in the next decade. Brazil and Indonesia are among the ones with the most ambitious restoration commitments globally. Since both their economies are highly dependent on the export of agricultural commodities, reconciling economic growth with environmental sustainability will be a major policy challenge. In this paper, we (a) identify the main restoration targets and the policies supporting their implementation in both countries, (b) provide a descriptive overview of these restoration-supportive policies, and (c) discuss the main challenges that Brazil and Indonesia face in the implementation of their restoration commitments. We find that Brazil has an explicit and dedicated strategy to achieve its restoration target, but that recent political developments have weakened environmental governance in the country, affecting the implementation of its restoration commitment. In the case of Indonesia, we find that the government has rather focused and progressed on the restoration of peatlands and mangroves, whereas its commitment to restore forestlands has yet to benefit from a dedicated plan that allows to coordinate policies and agencies’ efforts towards the achievement of its restoration target.Bundesministerium für Umwelt, Naturschutz, nukleare Sicherheit und Verbraucherschutz (BMUV)http://dx.doi.org/10.13039/501100006549Peer Reviewe

PREVALÊNCIA E CARACTERÍSTICAS CLÍNICAS DA DISFUNÇÃO TEMPOROMANDIBULAR EM PACIENTES COM ARTRITE IDIOPÁTICA JUVENIL POLIARTICULAR

Juvenile Idiopathic Arthritis (JIA) is a chronic autoimmune disease that affects children and adolescents, being the most common in childhood. Temporomandibular joint dysfunction (TMD) occurs in up to 87% of JIA cases, regardless of the subtype of the disease. Late diagnosis of TMD contributes to joint deformities, resulting in abnormal mandibular growth and dentofacial deformities, impairing quality of life. This qualitative integrative review, conducted in 2023, adopted the PICO strategy to explore the prevalence of TMD in patients with polyarticular juvenile idiopathic arthritis (JIA) and its impact on clinical management and quality of life. The search included national and international journals indexed in Science Direct, PubMed®, LILACS and Cochrane, using MeSH descriptors. Studies suc revealed an average prevalence of TMD of 12% in juvenile patients, while another pointed out a 40% prevalence of unilateral TMD in pediatric patients. The studies emphasized the need for multidisciplinary approaches, involving medical and dental professionals. The subsequent discussion will cover details about quality of life, signs and symptoms of JIA associated with TMD. The results highlight not only the high prevalence of these dysfunctions, but also the significant influence of this association on the clinical management and quality of life of patients with JIA.La Artritis Idiopática Juvenil (AIJ) es una enfermedad autoinmune crónica que afecta a niños y adolescentes, siendo la más común en la infancia. La disfunción de la articulación temporomandibular (DTM) ocurre hasta en el 87% de los casos de AIJ, independientemente del subtipo de la enfermedad. El diagnóstico tardío de TMD contribuye a las deformidades de las articulaciones, lo que resulta en un crecimiento mandibular anormal y deformidades dentofaciales, lo que perjudica la calidad de vida. Esta revisión integradora cualitativa, realizada en 2023, adoptó la estrategia PICO para explorar la prevalencia de TMD en pacientes con artritis idiopática juvenil (AIJ) poliarticular y su impacto en el manejo clínico y la calidad de vida. La búsqueda incluyó revistas nacionales e internacionales indexadas en Science Direct, PubMed®, LILACS y Cochrane, utilizando descriptores MeSH. Estudios revelaron una prevalencia promedio de TTM del 12% en pacientes juveniles, mientras que otros señalaron una prevalencia del 40% de DTM unilateral en pacientes pediátricos. Los estudios enfatizaron la necesidad de enfoques multidisciplinarios, que involucren a profesionales médicos y dentales. La discusión posterior cubrirá detalles sobre la calidad de vida, los signos y síntomas de AIJ asociados con TMD. Los resultados destacan no sólo la alta prevalencia de estas disfunciones, sino también la influencia significativa de esta asociación en el manejo clínico y la calidad de vida de los pacientes con AIJ.A Artrite Idiopática Juvenil (AIJ) é uma doença autoimune crônica que afeta crianças e adolescentes, sendo a mais comum na infância. A disfunção da articulação temporomandibular (DTM) ocorre em até 87% dos casos de AIJ, independentemente do subtipo da doença. O diagnóstico tardio da DTM contribui para deformidades articulares, resultando em crescimento mandibular anormal e deformidades dento faciais, prejudicando a qualidade de vida. Esta revisão integrativa qualitativa, conduzida em 2023, adotou a estratégia PICO para explorar a prevalência da DTM em pacientes com artrite idiopática juvenil poliarticular (AIJ) e seu impacto no manejo clínico e qualidade de vida. A busca incluiu periódicos nacionais e internacionais indexados em Science Direct, PubMed®, LILACS e Cochrane, utilizando descritores MeSH. Estudos revelaram uma prevalência média de 12% de DTM em pacientes juvenis, outros apontaram uma prevalência de 40% de DTM unilateral em pacientes infantis. Os estudos enfatizaram a necessidade de abordagens multidisciplinares, envolvendo profissionais médicos e odontológicos. A discussão posterior abordará detalhes sobre qualidade de vida, sinais e sintomas da AIJ associados à DTM. Os resultados destacam não apenas a alta prevalência dessas disfunções, mas também a influência significativa dessa associação no manejo clínico e qualidade de vida dos pacientes com AIJ.A Artrite Idiopática Juvenil (AIJ) é uma doença autoimune crônica que afeta crianças e adolescentes, sendo a mais comum na infância. A disfunção da articulação temporomandibular (DTM) ocorre em até 87% dos casos de AIJ, independentemente do subtipo da doença. O diagnóstico tardio da DTM contribui para deformidades articulares, resultando em crescimento mandibular anormal e deformidades dento faciais, prejudicando a qualidade de vida. Esta revisão integrativa qualitativa, conduzida em 2023, adotou a estratégia PICO para explorar a prevalência da DTM em pacientes com artrite idiopática juvenil poliarticular (AIJ) e seu impacto no manejo clínico e qualidade de vida. A busca incluiu periódicos nacionais e internacionais indexados em Science Direct, PubMed®, LILACS e Cochrane, utilizando descritores MeSH. Estudos revelaram uma prevalência média de 12% de DTM em pacientes juvenis, outros apontaram uma prevalência de 40% de DTM unilateral em pacientes infantis. Os estudos enfatizaram a necessidade de abordagens multidisciplinares, envolvendo profissionais médicos e odontológicos. A discussão posterior abordará detalhes sobre qualidade de vida, sinais e sintomas da AIJ associados à DTM. Os resultados destacam não apenas a alta prevalência dessas disfunções, mas também a influência significativa dessa associação no manejo clínico e qualidade de vida dos pacientes com AIJ

A representação visual auxiliando a comunicação para o beneficiamento do jeans: Visual representation aiding communication for the processing of jeans

Originalmente o denim se apresentava nas cores que variavam entre o azul e o verde amarronzado. Processos de acabamento começaram a ser empregados para agregar valor sensorial e posteriormente estético ao produto com valor de moda produzido com o denim. A roupa confeccionada com esse tecido passou a ser denominada jeans. Construir um fluxograma para auxiliar a visualização dos processos de beneficiamento do denim foi o objetivo do estudo que apresenta o jeans como uma roupa que veste todos os povos na atualidade

A Investigação e a escrita: Publicar sem Perecer

Research and Writing: Publish do not Perish is a collection of texts published in Portuguese, based on the problematization of a five-year experience of advanced extracurricular training in information literacy, writing and scientific publication (i.e., Publish do not Perish: Survive the Stampede). It is a questioning of the role of science in a context that appears to reproduce neoliberalism and the commodification of academia. This work results from the collaboration of national and international authors who consider a diversity of theoretical and empirical fields that deal with that phenomenon. This book aims to identify and question the subsequent problems, trying to point out solutions to the growing malaise in the academic world

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Assessment of mercury in sediments and in the benthic invertebrate Micronecta scholtzi downstream an abandoned pyrite mine

y: The drainage of abandoned mines leads to several ecological problems, particularly the acidification of surface freshwater systems and heavy metal contamination. Mercury (Hg) is of particular interest because of its high toxicity and its ability for bioaccumulation. This work evaluates the magnitude and pattern of Hg dissipation from an abandoned pyrite mines to the local water ecosystem by testing of the stream bottom sediments and water invertebrate Micronecta scholtzi along the pyrite-cupric mine drainage system. Overall results showed a high significant correlation (Pearson coefficient = 0.82 at p<0.05) between mercury levels in biota and those in sediments for all the sampling sites. In the sediments Hg concentrations ranged from 14.4-32.4 µg g-1 dw decreasing downstream to 3.67-5.3 µg g-1 due to natural dilution. Hg concentration in M. scholtzi showed a similar trend ranging from 3.6-12.6 µg g-1 dw at the mine pit and decreasing 5 Km downstream to 0.2-1.6 µg g-1 thus reflecting the significant Hg dissipation in surface sediments. Reported Hg levels in sediments were very high and significantly above threshold limits de-fined by the legislation for the protection of aquatic biota. The Hg in stream sediments derived from such mining areas is potentially hazardous to the environment adjacent to the abandoned mine and this work proves that Hg is mobilised from the mines and accumulated by local water biota, posing a risk to surrounding freshwater systems.Peer reviewe

Life-history responses of Daphnia magna Straus to binary mixtures of toxic substances: Pharmacological versus ecotoxicological modes of action

Two prevailing theoretical models: concentration addition (CA) and independent action (IA), predict mixture toxicity on the basis of known toxicities of the mixture components. To date, both models have been in most occasions evaluated using unicellular in vivo responses or biochemical in vitro responses. However, when considering more complex models such as the whole organism physiology or life-history traits, the dominant ecotoxicological mode of action, based on the exposure concentrations at which various toxicological effects become operative at the level of whole organism, should be considered. Offspring production in Daphnia magna is driven by the resources acquired from food, and the number of live offspring produced by an organism is the result of two independent factors: the number of eggs produced and the percentage of eggs that survive egg development. In this study joint toxicity effects on offspring production in D. magna were tested using binary mixtures of toxic contaminants known to specifically impair food acquisition (lambda-cyhalothrin and cadmium) or to cause egg mortality during development (3,4 dichloroaniline). Tests were performed using a simplified 10-day reproduction assay initiated with gravid females. The results obtained indicate that irrespective of their primary pharmacological mode of action, the joint toxicity of cadmium and X-cyhalothrin was predicted by the CA model, whereas the joint toxicity of cadmium and 3,4 dichloroaniline was predicted by the IA model. Thus, the results obtained indicate that for life-history traits such as reproduction responses, the dominant ecotoxicological rather than the pharmacological mode of action should be used for predicting joint mixture effects. (c) 2007 Elsevier B.V. All rights reserved.COMBITOOL project - REN 2003-06917-CO2-O2CEMUGA - CGL2007- 64551/HIDFC