RESUMEN
The occurrence of clinically significant changes in empathy is a matter of debate in Alzheimer's disease (AD). Altered empathic mechanisms observed in AD may be a consequence of cognitive impairment, more specifically of reduced mental flexibility and self-regulation. The present study explored possible changes in empathy for subjects in the prodromal phase of AD, namely mild cognitive impairment (MCI) due to AD, and of their neural substrates. Eighteen MCI patients and 20 healthy controls (HC) were included in the study. The Interpersonal Reactivity Index (IRI) questionnaire was administered to each participant. The IRI encompasses four factors: Perspective Taking; Fantasy; Empathic Concern; Personal Distress. MCI patients underwent a magnetic resonance imaging structural examination and were compared to 30 healthy controls (HC-MRI). A limited number of cortical and subcortical regions involved in social cognition was selected as regions of interest (ROIs). MCI individuals obtained lower scores than HC in the Perspective Taking and Fantasy subscales of the IRI, whereas they obtained higher scores on Empathic Concern. Regarding neuroimaging data, a significant correlation emerged between IRI scores and the neural measurements of different regions involved in empathy, especially covering the temporoparietal junction, which is a critical region engaged in both affective and cognitive dimensions of empathy. The results of the present study suggest that a subtle impairment in regulatory mechanisms of empathy may occur very early during the course of AD, possibly as a consequence of neuropathological changes occurring in brain regions involved in social cognition.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Empatía , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/psicología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Enfermedad de Alzheimer/diagnóstico por imagen , Imagen por Resonancia MagnéticaRESUMEN
In the last 30 years a plethora of phylogeography studies have been published targeting Brazilian marine species. To date, several historical and extant physical and ecological processes have been identified as drivers of allopatric, sympatric and parapatric population genetic differentiation detected along the Brazilian coast. Examples of extant physical barriers include the split of the South Equatorial Current into the Brazil and North Brazil boundary currents, the mouth of major rivers (e.g., Amazon, São Francisco and Doce rivers) and coastal upwellings. Examples of historical barriers include the Vitória-Trindade seamount chain promoting genetic differentiation during periods of glacial maxima and lower sea levels. Examples of ecological speciation include adaptations to different substrata, resource use and reproductive biology. We used published data to build data sets and generalized additive models to identify patterns of spatial phylogeographical concordance across multiple taxa and markers. Our results identify Cape São Roque as the most dominant extant barrier to gene flow along the Brazilian coast, followed by the Vitória-Trindade seamount chain and Cape Santa Marta. Cape Santa Marta is the northern winter limit of the Rio da Plata plume and is intermittently influenced by the Malvinas Current. This study provides a novel explicit quantitative approach to comparative phylogeography that recognizes four Brazilian phylogeographical regions delimited by processes associated with barriers to gene flow.
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Flujo Génico , Variación Genética , Filogeografía , Brasil , Filogenia , ADN Mitocondrial/genéticaRESUMEN
Colpomenia sinuosa is a cosmopolitan brown macroalgal species complex and hence a great candidate for evolutionary studies in the marine environment. Since 2009, three major C. sinuosa phylogenetic lineages, subdivided into eight subgroups, have been identified based on cox3 DNA sequences from worldwide collections. However, worldwide sampling remains limited and spotty. To date molecular data from Brazilian C. sinuosa populations have been limited to 10 specimens collected in a single locality. Nonetheless, C. sinuosa populations occur along the entire ~8,000 km Brazilian coast. Consequently, knowledge on population genetic diversity and spatial genetic structuring along most of the Brazilian coastline is nonexistent. To fulfill this gap in knowledge, we performed a phylogeographic analysis of C. sinuosa populations in Brazil. The highly variable cox3 marker was sequenced for 148 individuals collected in 12 localities in Brazil. Results identified two genetically distinct population groups (north vs. south) separated at 20.5° S latitude. Genetic diversity in northern populations is 14.6 and 15.5 times greater than southern populations in terms of haplotype and nucleotide diversity, respectively. Among northern populations, the Bahia state holds the largest genetic diversity. The southern populations had lower genetic diversity and no internal genetic sub-structure suggesting past bottlenecks followed by recent colonization from northern haplotypes. Our results do not indicate recent introductions of foreign haplotypes in Brazil and reinforce the crucial importance of historical and extant allopatric, parapatric, and sympatric processes driving marine macroalgal evolution in the Southwestern Atlantic Ocean.
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ADN Mitocondrial , Phaeophyceae , Brasil , ADN Mitocondrial/genética , Variación Genética , Genética de Población , Haplotipos , Phaeophyceae/genética , Filogenia , FilogeografíaRESUMEN
The Peyssonneliaceae represents the only family in the order Peyssonneliales, a clade of red encrusting algae distributed worldwide, including 136 species in eleven currently accepted genera. Delineation of genera in the Peyssonneliaceae has mostly been based on vegetative characteristics. Previous molecular phylogenies have shown that some traditionally circumscribed genera are not monophyletic and relationships among them are uncertain. We contribute to the knowledge of the evolutionary history of this clade, presenting a robust rbcL phylogeny that provides new insights on the origin and diversification of the Peyssonneliales. Based on a broad dataset and morphological analyses, we propose a revised taxonomic scheme for the Peyssonneliales resolved as monophyletic with well-supported main lineages. Our results show that Peyssonnelia is polyphyletic, and, therefore, we propose three new genera, Agissea, Olokunia, and Rhodowynnea to accommodate species currently assigned to Peyssonnelia, but distantly related to the clade with the type species of the genus. Additionally, barcoding techniques and analyzed criteria for specific delimitation supported the establishment of one new genus, Brasilophycus, and seven new species, from northeastern Brazil: Agissea amadoi, A. densissima, A. taberniforma, A. villatlantica, A. yemonjasagbae, Brasilophycus similis, and B. roseomarginatus. Our integrative taxonomic approach reveals underestimated diversity of Brazilian Peyssonneliales. Investment in broader sampling along the Brazilian coast and other tropical areas may reveal that its marine biodiversity can be expanded, enlightening our knowledge about this ecologically important group of red algae.
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Rhodophyta , Biodiversidad , Evolución Biológica , Brasil , Filogenia , Rhodophyta/genéticaRESUMEN
INTRODUCTION: Healthy elderly, mild cognitive impairment and Alzheimer's disease populations have been among the most affected in the early stages of the COVID-19 pandemic due to the direct effects of the virus, and numerous indirect effects now emerge and will have to be carefully assessed over time. METHODS: This article reviews the main articles that have been published so far about the direct and indirect effects of the COVID-19 pandemic on these particularly fragile populations. RESULTS: The pandemic associated to COVID-19 has shifted most of the health resources to the emergency area and has consequently left the three main medical areas dealing with the elderly population (oncology, time-dependent diseases and degenerative disease) temporarily "uncovered". In the phase following the emergency, it will be crucial to guarantee to each area the economic and organizational resources to quickly return to the level of support of the prepandemic state. CONCLUSIONS: The emergency phase represented a significant occasion of discussion on the possibilities of telemedicine which will inevitably become increasingly important, but all the limits of its use in the elderly population have to be considered. In the post-lockdown recovery phase, alongside the classic medical evaluation, the psychological evaluation must become even more important for doctors caring about people with cognitive decline as well as with their caregivers.
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Envejecimiento , Enfermedad de Alzheimer , COVID-19 , Disfunción Cognitiva , Atención a la Salud , Recursos en Salud , Enfermedad de Alzheimer/terapia , Disfunción Cognitiva/terapia , HumanosRESUMEN
As marine tropical ecosystems deteriorate and lose biodiversity, their communities are shifting to being dominated by a few species, altering ecosystem's functioning and services. Macroalgae are becoming dominant on coral reefs, and are frequently observed outcompeting corals. Turf algal assemblages are the base of energy flow in these systems and one of the most abundant types of macroalgae on coral reefs, but little is known about their biology and diversity. Through molecular and morphological analyses, we identified the turf-forming species Laurencia cervicornis, and by studying seasonal recruitment and the impact of herbivorous fishes on its abundance, we describe its survival strategy. The molecular analyses used a total of 45 rbcL gene sequences including eight current genera within the Laurencia complex and two new sequences of L. cervicornis and strongly support the new combination of Palisada cervicornis comb. nov. In addition, a detailed morphological characterization including the description of reproductive structures is provided. Palisada cervicornis was seen recruiting in all seasons but was typically in low abundance. Specimens grown on tiles in fish exclosure cages were devoured in less than 4 h when offered to fishes. Even though many species of the Laurencia complex have chemicals that deter herbivory, species within the genus Palisada lack feeding deterrents and thus are highly palatable. We suggest that P. cervicornis is a palatable species that seems to survive in the community by obtaining a size-refuge from herbivory within turf communities.
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Arrecifes de Coral , Rasgos de la Historia de Vida , Rhodophyta/fisiología , Algas Marinas/fisiología , Proteínas Algáceas/genética , Florida , Filogenia , Dinámica Poblacional , Rhodophyta/clasificación , Rhodophyta/genética , Ribulosa-Bifosfato Carboxilasa/genética , Estaciones del Año , Algas Marinas/clasificación , Algas Marinas/genética , Análisis de Secuencia de ADNRESUMEN
Hypnea has an intricate nomenclatural history due to a wide pantropical distribution and considerable morphological variation. Recent molecular studies have provided further clarification on the systematics of the genus; however, species of uncertain affinities remain due to flawed taxonomic identification. Detailed analyses coupled with literature review indicated a strong relationship among H. aspera, H. cervicornis, H. flexicaulis, and H. tenuis, suggesting a need for further taxonomic studies. Here, we analyzed sequences from two molecular markers (COI-5P and rbcL) and performed several DNA-based delimitation methods (mBGD, ABGD, SPN, PTP and GMYC). These molecular approaches were contrasted with morphological and phylogenetic evidence from type specimens and/or topotype collections of related species under a conservative approach. Our results demonstrate that H. aspera and H. flexicaulis represent heterotypic synonyms of H. cervicornis and indicate the existence of a misidentified Hypnea species, widely distributed on the Brazilian coast, described here as a new species: H. brasiliensis. Finally, inconsistencies observed among our results based on six different species delimitation methods evidence the need for adequate sampling and marker choice for different methods.
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Filogenia , Rhodophyta/clasificación , Proteínas Algáceas/genética , Brasil , Código de Barras del ADN Taxonómico , Rhodophyta/anatomía & histología , Rhodophyta/genética , Análisis de Secuencia de ADN , Especificidad de la EspecieRESUMEN
Species diversity within the genus Osmundea in the Macaronesian region was explored by conducting a comprehensive sampling in the Azores, the Canary, and the Madeira archipelagos. Toward identification, all specimens were first observed alive to verify the absence of corps en cerise, a diagnostic character for the genus and morphometric data were measured (thallus length and width, first-order branches length and width, branchlets length and width, cortical cell length and width in surface view, cortical cell length and width in transverse section). Specimens were sequenced for COI-5P (39 specimens) and three species delimitation methods (Generalized Mixed Yule Coalescent, Automatic Barcode Gap Discovery method, and Poisson Tree Processes) were used to assess the threshold between infra- and interspecific relationships. Subsequently, one or several sequences of plastid-encoded large subunit of RuBisCO (21 specimens) per delimited species were generated to assess the phylogenetic relationships among Macaronesian Osmundea. Moreover, for each delineated species, vegetative and reproductive anatomy was thoroughly documented and, when possible, specimens were either assigned to existing taxa or described as novel species. This integrative approach has provided data for (i) the presence of O. oederi, O. pinnatifida, and O. truncata in Macaronesia; (ii) the proposal of two novel species, O. prudhommevanreinei sp. nov. and O. silvae sp. nov.; and (iii) evidence of an additional species referred as "Osmundea sp.1," which is a sister taxon of O. hybrida.
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Biodiversidad , Filogenia , Rhodophyta/clasificación , Proteínas Algáceas/genética , Islas del Atlántico , Azores , Código de Barras del ADN Taxonómico , Portugal , Rhodophyta/citología , Rhodophyta/genética , Análisis de Secuencia de ADN , EspañaRESUMEN
In order to evaluate the chemical diversity of Laurencia dendroidea J. Agardh, a widely distributed seaweed in Brazilian coast, a phytochemical study was carried out with algae collected from six different locations along the Southeast Brazilian coast. Purified compounds were identified by MS and NMR techniques. The chemical profiles of lipophilic extracts were obtained by GC/MS for each population. In total, 15 compounds were described. The sesquiterpene composition accounted for 49 - 63% of the GC/MS chromatogram area. The discrimination of three chemotypes was done by the use of HCA on GC/MS chromatograms. They were also analyzed by the PCA and, together with peak area analysis, it was possible to discriminate all populations by the main variation of elatol, obtusol, rogiolol, and triquinane. The results revealed the high diversity of sesquiterpene composition among populations of L. dendroidea. Curiously, the within and among population variation of elatol and obtusol suggested a biochemical interplay on the content of these compounds. More studies are necessary to understand the patterns of chemical diversity and compound variation within and among populations of L. dendroidea.
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Productos Biológicos/análisis , Productos Biológicos/química , Laurencia/metabolismo , Productos Biológicos/metabolismo , Brasil , Laurencia/química , Conformación Molecular , Análisis de Componente PrincipalRESUMEN
Two new chamigrane sesquiterpenes 1-2 and three known compounds 3-5 were isolated from a lipophilic extract of the red alga Laurencia dendroidea collected from the Southeastern Brazilian coast. Dendroidone (1) and dendroidiol (2) were isolated from samples collected at Biscaia Inlet, Angra dos Reis, Rio de Janeiro and at Manguinhos Beach, Serra, Espírito Santo, respectively. Debromoelatol (3), obtusane (4) and (1S*,2S*,3S*,5S*,8S*,9S*)-2,3,5,9-tetramethyltricyclo[6.3.0.0¹·5]undecan-2-ol (5) were obtained from specimens collected at Vermelha Beach, Parati, Rio de Janeiro. The structures of new compounds were elucidated by extensive NMR (¹H-, ¹³C-, COSY, HSQC, HMBC and NOESY) and high resolution mass spectrometry analysis. Additionally, the absolute configuration of compound 2 was assigned by X-ray analysis. Full spectroscopic data is described for the first time for compound 3. Anti-inflammatory and antimycobacterial activities of compounds 2-5 were evaluated. Compounds 3-5 inhibited the release of inflammatory mediator NO while TNF-α levels were only affected by 3. All compounds tested displayed moderate antimycobacterial action.
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Laurencia/química , Extractos Vegetales/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Animales , Línea Celular , Concentración 50 Inhibidora , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Óxido Nítrico/biosíntesis , Resonancia Magnética Nuclear Biomolecular , Factor de Necrosis Tumoral alfa/biosíntesisRESUMEN
Abstract Brazil is characterized as a megadiverse country, and one of the factors that guarantees the knowledge and preservation of this biodiversity is an improvement in the biological collections. They represent a country's biological, scientific, cultural, and genetic heritage and their preservation depends on a joint effort of researchers, institutions, and public authorities. Marine biological collections of invertebrates and algae of the state of São Paulo represent a high percentage of the national collections, with five biological collections deposited in state institutions. Currently, these collections safeguard the vast majority of the state's marine collection and make up one of the largest in the country. Therefore, the objective of this research is to present information on marine biological collections in the state of São Paulo, their current status, funding, and future perspectives, creating communication opportunities and considering the factors that impact their development. Support from the São Paulo Research Foundation (FAPESP) surpasses state limits, since many studies address broader areas and/or establish diverse partnerships with other institutions from outside São Paulo. This is reflected in the taxonomic and geographic scope of the biological collections in the state, since these host specimens/species from different regions of the country, or even from other countries. However, it is worth mentioning that it is not enough to invest in expeditions to enrich the collections without valuing the training of qualified personnel, both for the collections maintenance and for their taxonomic refinement.
Resumo O Brasil é caracterizado como um país megadiverso e uma das prioridades no conhecimento e conservação dessa biodiversidade é seguramente a melhoria das coleções biológicas. Estas representam patrimônio biológico, científico, cultural e genético de um país, e sua preservação depende de um esforço coletivo de pesquisadores, instituições e do poder público. Com relação às coleções biológicas marinhas de invertebrados e algas, o estado de São Paulo representa uma alta porcentagem do acervo nacional, com cinco principais coleções depositadas em instituições estaduais. Atualmente estas coleções salvaguardam a grande maioria do acervo marinho estadual e compõem um dos maiores do país. Assim sendo, o objetivo desta pesquisa é o de apresentar informações sobre as coleções biológicas marinhas do estado de São Paulo, estado atual, financiamentos e perspectivas futuras, criando oportunidades de comunicação e considerando os fatores que impactam o desenvolvimento das mesmas. O apoio financeiro da Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) às instituições paulistas extravasa os limites do estado, visto que muitas pesquisas abordam áreas mais abrangentes e/ou estabelecem parcerias diversas com outras instituições não paulistas. Isso se reflete inclusive na abrangência taxonômica e geográfica das coleções biológicas do Estado, uma vez que estas mantêm espécimes/espécies de diferentes regiões do país, ou mesmo de outros países. No entanto, vale ressaltar que não basta investir em expedições de coleta para enriquecimento das coleções sem valorizar a formação de pessoal qualificado, tanto para a curadoria dos acervos quanto para o refinamento taxonômico.
RESUMEN
Laurencia marilzae Gil-Rodríguez, Sentíes et M.T. Fujii sp. nov. is described based on specimens that have been collected from the Canary Islands. This new species is characterized by distinctive yellow-orange as its natural habitat color, a terete thallus, four pericentral cells per vegetative axial segment, presence of secondary pit-connections between adjacent cortical cells, markedly projecting cortical cells, and also by the presence of corps en cerise (one per cell) present in all cells of the thallus (cortical, medullary, including pericentral and axial cells, and trichoblasts). It also has a procarp-bearing segment with five pericentral cells and tetrasporangia that are produced from the third and fourth pericentral cells, which are arranged in a parallel manner in relation to fertile branchlets. The phylogenetic position of this taxon was inferred based on chloroplast-encoded rbcL gene sequence analyses. Within the Laurencia assemblage, L. marilzae formed a distinctive lineage sister to all other Laurencia species analyzed. Previously, a large number of unique diterpenes dactylomelane derivatives were isolated and identified from this taxon. L. marilzae is morphologically, genetically, and chemically distinct from all other related species of the Laurencia complex described.
RESUMEN
Different species of Laurencia have proven to be a rich source of natural products yielding interesting bioactive halogenated secondary metabolites, such as terpenoids and acetogenins. It is shown that such compounds are accumulated in the spherical, reniform to claviform refractive inclusions called corps en cerise (CC), which are intensively osmiophilic and located mainly in the cortical cells of the thalli and also in trichoblast cells. Up to now, it was believed that CC were present only in these two kinds of cells. Recently, however, a species of Laurencia, L. marilzae, with CC in all cells of the thallus, i.e., cortical, medullary, including the pericentral and axial cells, as well as in the trichoblasts, was described from the Canary Islands, and subsequently also reported to Brazil and Mexico. Within the Laurencia complex, only Laurencia species produce CC. Since the species of Laurencia are targets of interest for the prospection of bioactive substances due to their potential antibacterial, antifungal, anticholinesterasic, antileishmanial, cytotoxic, and antioxidant activities, the present paper carries out a comparative analysis of the corps en cerise in several species of Laurencia from the Atlantic Ocean to obtain basic information that can support natural product bioprospection projects. Our results show that the number and size of the CC are constant within a species, independent of the geographical distribution, corroborating their use for taxonomical purposes to differentiate groups of species that present a lower number from those that have a higher number. In this regard, there was a tendency for the number of CC to be higher in some species of Laurencia from the Canary Islands. The presence of CC can also be used to distinguish species in which these organelles are present in all cells of the thallus from those in which CC are restricted to the cortical cells. Among the species analyzed, L. viridis displayed the most varied secondary metabolites composition, such as sesquiterpenes, diterpenes, triterpenes, all of which showed potent antiviral, cytotoxic, and antitumoral activities, including protein phosphatase type 2A (PP2A) inhibitory effects.
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Morphological and molecular studies were carried out on Laurencia oliveirana from the type locality (Arraial do Cabo, Rio de Janeiro, Brazil). This species is easily recognized by its small size, sub-erect habit forming intricate cushion-like tufts and unilateral pectinate branching. The species displays all the typical characters of the genus Laurencia, such as the production of the first pericentral cell underneath the basal cell of the trichoblast, tetrasporangia produced from particular pericentral cells, with the third and fourth pericentral cells becoming fertile, without production of additional pericentral cells, spermatangial branches produced from one of two laterals on the suprabasal cell of trichoblasts, and procarp-bearing segment with five pericentral cells. Details of tetrasporangial plants and development of procarp and male plants are described for the first time for the species. The phylogenetic position of L. oliveirana was inferred by analysis of the chloroplast-encoded rbcL gene sequences from 57 taxa. In all phylogenetic analyses, L. oliveirana grouped with L. caraibica, L. caduciramulosa, L. venusta and L. natalensis, forming a monophyletic clade within the Laurencia sensu stricto. The genetic divergence between L. oliveirana and the molecularly closest species, L. caraiba collected in Brazil, was 2.3%.
RESUMEN
In Brazil, the Laurencia complex is represented by twenty taxa: Laurencia s.s. with twelve species, Palisada with four species (including Chondrophycus furcatus now that the proposal of its transference to Palisada is in process), and Osmundea and Yuzurua with two species each. The majority of the Brazilian species of the Laurencia complex have been phylogenetically analyzed by 54 rbcL sequences, including five other Rhodomelacean species as outgroups. The analysis showed that the Laurencia complex is monophyletic with high posterior probability value. The complex was separated into five clades, corresponding to the genera: Chondrophycus, Laurencia, Osmundea, Palisada, and Yuzurua. A bibliographical survey of the terpenoids produced by Brazilian species showed that only six species of Laurencia and five of Palisada (including C. furcatcus) have been submitted to chemical analysis with 48 terpenoids (47 sesquiterpenes and one triterpene) isolated. No diterpenes were found. Of the total, 23 sesquiterpenes belong to the bisabolane class and eighteen to the chamigrene type, whose biochemical precursor is bisabolane, two are derived from lauranes and four are triquinols. Despite the considerable number of known terpenes and their ecological and pharmacological importance, few experimental biological studies have been performed. In this review, only bioactivities related to human health were considered.