Repositório RCAAP

Biodiversity varies with elevation and is affected by disturbances. However, little is known about how the associations between the diversities of different bryophyte and macrolichen functional-taxonomic groups are altered along elevational gradients and by disturbances. Knowledge on the associations between these functional-taxonomic groups might be of importance in practical conservation biology, as identifying indicator taxa which are easy to monitor could be useful in estimating a wider biodiversity. We sampled the species richness of bryophytes and macrolichens in 92 plots distributed in disturbed and undisturbed stands along elevational gradients in the laurel forest of Madeira. We then calculated a matrix of correlations for all pairwise combinations of 18 different functional-taxonomic bryophyte and macrolichen groups and tested for average differences in correlations with elevation and disturbance history and whether particular functional-taxonomic groups can be used to estimate the richness of other taxa. Associations between the diversities of functional-taxonomic groups within the bryophyte group and within the macrolichen group were always positive and mainly strong. Although changes in elevation and disturbance history changed the associations between the different bryophyte and macrolichen functional-taxonomic groups, we found the species richness of mosses or liverworts to be suitable for predicting overall bryophyte species richness and the species richness of green-algae macrolichens to be reliable for estimating overall macrolichen species richness. Associations between diversities of bryophyte and macrolichen groups were generally weak, suggesting that the two groups have different ecological requirements and do not share the same environmental drivers. The fact that no single bryophyte taxon can be used to predict the richness of any macrolichen group, and vice versa, points to the need to study both bryophytes and lichens. However, we found indicator taxa that are relatively easy to monitor and therefore could be used to estimate the wider biodiversity.

Background: subthalamic nucleus deep brain stimulation (STN-DBS) may have a detrimental effect on speech in Parkinson's disease (PD) patients and new stimulation technologies may help in addressing this issue. Objective: to evaluate the STN-DBS acute effect of 30 μs pulse width (30PW) versus conventional 60 μs PW (60PW) on speech and identify the core features of voice modified by 30PW. Methods: seven STN-DBS treated PD patients participated into a pilot cross-sectional study. Motor and speech performances were tested by means of both automatic analysis and blinded clinical evaluations in four stimulation conditions: 30PW and 60PW both at the usual amplitude and at an amplitude just below the threshold for stimulation-related side effects. Results: at the threshold amplitude, 30PW stimulation improved speech intelligibility for both words (p = 0.02) and sentences (p = 0.04), without worsening motor performance. A lower but not statistically significant voice variability and instability and percentage of stuttering disfluencies was also observed. The beneficial effect of 30PW detected by automatic analysis, was confirmed by patients' perception. Conclusions: STN-DBS treated patients experiencing low speech intelligibility may benefit from a 30PW stimulation trial at a higher amplitude. Deep characterization of PD speech profiles may help in a better application of recent DBS hardware advances.

Introduction: Although in some countries, palliative care (PC) still remains poorly implemented, its importance throughout the course of Parkinson's disease (PD) is increasingly being acknowledged. With an emergence of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) pandemic, growing emphasis has been placed on the palliative needs of people with Parkinson's (PwP), particularly elderly, frail, and with comorbidities.Areas covered: The ongoing COVID-19 pandemic poses an enormous challenge on aspects of daily living in PwP and might interact negatively with a range of motor and non-motor symptoms (NMS), both directly and indirectly - as a consequence of pandemic-related social and health care restrictions. Here, the authors outline some of the motor and NMS relevant to PC, and propose a pragmatic and rapidly deployable, consensus-based PC approach for PwP during the ongoing COVID-19 pandemic, potentially relevant also for future pandemics.Expert opinion: The ongoing COVID-19 pandemic poses a considerable impact on PwP and their caregivers, ranging from mental health issues to worsening of physical symptoms - both in the short- and long-term, (Long-COVID) and calls for specific, personalized PC strategies relevant in a lockdown setting globally. Validated assessment tools should be applied remotely to flag up particular motor or NMS that require special attention, both in short- and long-term.

Background: In the last years, several studies were conducted that evaluated biomarkers that could be helpful for cardioembolic stroke diagnosis, prognosis, and the determination of risk of stroke recurrence. Methods: We performed a narrative review of the main studies that evaluated biomarkers related to specific cardioembolic causes: atrial fibrillation, patent foramen ovale, atrial cardiomyopathy, and left ventricular wall motion abnormalities. Results: BNP and NT-proBNP are, among all biomarkers of cardioembolic stroke, the ones that have the highest amount of evidence for their use. NT-proBNP is currently used for the selection of patients that will be included in clinical trials that aim to evaluate the use of anticoagulation in patients suspected of having a cardioembolic stroke and for the selection of patients to undergo cardiac monitoring. NT-proBNP has also been incorporated in tools used to predict the risk of stroke recurrence (ABC-stroke score). Conclusions: NT-proBNP and BNP continue to be the biomarkers most widely studied in the context of cardioembolic stroke. The possibility of using other biomarkers in clinical practice is still distant, mainly because of the low methodological quality of the studies in which they were evaluated. Both internal and external validation studies are rarely performed for most biomarkers.

A 62-year-old woman recently arrived from Angola to start treatment for a papillary adenocarcinoma of the endometrium presented to the emergency room complaining of asthenia and anorexia.

The unique capabilities of gamma-delta (γδ) T cells to recognize cells under stressed conditions, particularly infected or transformed cells, and killing them or regulating the immune response against them, paved the way to the development of promising therapeutic strategies for cancer and infectious diseases. From a mechanistic standpoint, numerous studies have unveiled a remarkable flexibility of γδ T cells in employing their T cell receptor and/or NK cell receptors for target cell recognition, even if the relevant ligands often remain uncertain. Here, we review the accumulated knowledge on the diverse mechanisms of target cell recognition by γδ T cells, focusing on human γδ T cells, to provide an integrated perspective of their therapeutic potential in cancer and infectious diseases.

There is limited information on the serotypes causing non-invasive pneumococcal pneumonia (NIPP). Our aim was to characterize pneumococci causing NIPP in adults to determine recent changes in serotype prevalence, the potential coverage of pneumococcal vaccines and changes in antimicrobial resistance. Serotypes and antimicrobial susceptibility profiles of a sample of 1300 isolates recovered from adult patients (≥18 yrs) between 1999 and 2011 (13 years) were determined. Serotype 3 was the most frequent cause of NIPP accounting for 18% of the isolates. The other most common serotypes were 11A (7%), 19F (7%), 19A (5%), 14 (4%), 22F (4%), 23F (4%) and 9N (4%). Between 1999 and 2011, there were significant changes in the proportion of isolates expressing vaccine serotypes, with a steady decline of the serotypes included in the 7-valent conjugate vaccine from 31% (1999-2003) to 11% (2011) (P<0.001). Taking together the most recent study years (2009-2011), the potential coverage of the 13-valent conjugate vaccine was 44% and of the 23-valent polysaccharide vaccine was 66%. While erythromycin resistance increased from 8% in 1999-2003 to 18% in 2011 (P<0.001), no significant trend was identified for penicillin non-susceptibility, which had an average value of 18.5%. The serotype distribution found in this study for NIPP was very different from the one previously described for IPD, with only two serotypes in common to the ones responsible for half of each presentation in 2009-2011 - serotypes 3 and 19A. In spite of these differences, the overall prevalence of resistant isolates was similar in NIPP and in IPD.

Several studies conducted worldwide report an inverse association between caffeine/coffee consumption and the risk of developing Parkinson's disease (PD). However, heterogeneity and conflicting results between studies preclude a correct estimation of the strength of this association. We conducted a systematic review and meta-analysis of published epidemiological studies to better estimate the effect of caffeine exposure on the incidence of PD. Data sources searched included Medline, LILACS, Scopus, Web of Science and reference lists, up to September 2009. Cohort, case-control and cross-sectional studies were included. Three independent reviewers selected the studies and extracted the data on to standardized forms. Twenty-six studies were included: 7 cohort, 2 nested case-control, 16 case-control, and 1 cross-sectional study. Quantitative data synthesis of the most precise estimates from each study was accomplished through random effects meta-analysis. Heterogeneity was quantified using the I2 statistic. The summary RR for the association between caffeine intake and PD was 0.75 [[95% Confidence Interval (95%CI): 0.68-0.82], with low to moderate heterogeneity (I2= 28.8%). Publication bias for case-control/cross-sectional studies may exist (Egger's test, p=0.053). When considering only the cohort studies, the RR was 0.80 (95%CI: 0.71-90; I2=8.1%). The negative association was weaker when only women were considered (RR=0.86, 95%CI: 0.73-1.02; I2=12.9%). A linear relation was observed between levels of exposure to caffeine and the RR estimates: RR of 0.76 (95%CI: 0.72-0.80; I2= 35.1%) per 300 mg increase in caffeine intake. This study confirm an inverse association between caffeine intake and the risk of PD, which can hardly by explained by bias or uncontrolled confounding.

Background and purpose: NMDA receptors play a key role in both synaptic plasticity and neurodegeneration. Adenosine is an endogenous neuromodulator and through membrane receptors of the A2A subtype can influence both synaptic plasticity and neuronal death. The present work was designed to evaluate the influence of adenosine A2A receptors upon NMDA receptor activity in CA1 hippocampal neurons. We discriminated between modulation of synaptic versus extrasynaptic receptors, since extrasynaptic NMDA receptors are mostly associated with neurodegeneration while synaptic NMDA receptors are linked to plasticity phenomena. Experimental approach: Whole-cell patch-clamp recordings were obtained to evaluate NMDA receptor actions on CA1 pyramidal neurons of young adult (5-10 weeks) male Wistar rat hippocampus. Key results: Activation of A2A receptors with CGS 21680 (30 nM) consistently facilitated chemically-evoked NMDA receptor-currents (NMDA-PSCs) and afferent-evoked NMDA-currents (NMDA-EPSCs), an action prevented by an A2A receptor antagonist (SCH58261, 100 nM) and a PKA inhibitor, H-89 (1 μM). These actions did not reflect facilitation in glutamate release since there was no change in NMDA-EPSCs paired pulse ratio. A2A receptor actions were lost in the presence of an open-channel NMDA receptor blocker, MK-801 (10 μM), but persisted in the presence of memantine, at a concentration (10 μM) known to preferentially block extrasynaptic NMDA receptors. Conclusion and implications: These results show that A2A receptors exert a positive postsynaptic modulatory effect over synaptic, but not extrasynaptic, NMDA receptors in CA1 neurons and, therefore, under non-pathological conditions may contribute to shift the dual role of NMDA receptors towards enhancement of synaptic plasticity.

Delivering healthcare to people living with Parkinson's disease (PD) may be challenging in face of differentiated care needs during a PD journey and a growing complexity. In this regard, integrative care models may foster flexible solutions on patients' care needs whereas Parkinson Nurses (PN) may be pivotal facilitators. However, at present hardly any training opportunities tailored to the care priorities of PD-patients are to be found for nurses. Following a conceptual approach, this article aims at setting a framework for training PN by reviewing existing literature on care priorities for PD. As a result, six prerequisites were formulated concerning a framework for training PN. The proposed training framework consist of three modules covering topics of PD: (i) comprehensive care, (ii) self-management support and (iii) health coaching. A fourth module on telemedicine may be added if applicable. The framework streamlines important theoretical concepts of professional PD management and may enable the development of novel, personalized care approaches.

Physiological network functioning in the hippocampus is dependent on a balance between glutamatergic cell excitability and the activity of diverse local circuit neurons that release the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Tuners of neuronal communication such as adenosine, an endogenous modulator of synapses, control hippocampal network operations by regulating excitability. Evidence has been recently accumulating on the influence of adenosine on different aspects of GABAergic transmission to shape hippocampal function. This review addresses how adenosine, through its high-affinity A1 (A1 R) and A2A receptors (A2A R), interferes with different GABA-mediated forms of inhibition in the hippocampus to regulate neuronal excitability. Adenosine-mediated modulation of phasic/tonic inhibitory transmission, of GABA transport mechanisms and its interference with other modulatory systems are discussed together with the putative implications for neuronal function in physiological and pathological conditions. This article is part of a mini review series: 'Synaptic Function and Dysfunction in Brain Diseases'.

Background: Verbal language deteriorates in Alzheimer's disease, contributing to dramatic disturbances in the ability to communicate. The presence of language disturbances may be detected at earlier phases of the neurodegenerative process, like mild cognitive impairment (MCI). In daily verbal interactions, people mostly use literal language, but sometimes they employ non-literal language, which requires listeners to interpret messages beyond the plain meaning of the words and can be quite demanding. In the present study, we tested the hypotheses that patients with MCI may have deficits in non-literal language, and these deficits are more pronounced than deficits in literal language. Methods: Participants were recruited in a private memory clinic and senior universities. General cognitive evaluation included a comprehensive neuropsychological battery, the Mini-Mental State Examination, and the instrumental activities of daily living scale. Literal language was assessed with the semantic decision test, Token Test, and literal text comprehension test, and non-literal language with the proverbs comprehension, idiomatic expressions and non-literal text comprehension tests. Results: Fifty-two participants with MCI and 31 controls were recruited. Patients with MCI had lower scores in all complex language tests, both literal (Token Test, semantic decision and literal text) and non-literal (proverbs, idiomatic expressions, and non-literal text), than the controls; the difference in literal text score was marginally significant. As much as 69% of MCI participants had deficits (performance below 1.5 SD of the mean) on at least one of the complex language tasks. Deficits were more frequent on the proverbs comprehension and semantic decision tests, and the deficits on these tests did not significantly differ from that on the Token Test. Conclusion: Patients with MCI are hindered in understanding complex language, both literal and non-literal. In daily living, these complex language deficits could compromise effective verbal interactions with the others. Amelioration of these deficits should be an important intervention target as part of a comprehensive rehabilitation strategy for patients with cognitive decline.

The fifth international γδ T-cell conference was held in Freiburg, Germany, from May 31 to June 2, 2012, bringing together approximately 170 investigators from all over the world. The scientific program covered topics such as thymic development and the mechanisms of ligand recognition and activation, the interaction of γδ T cells with other immune and non-immune cells and its implications for homeostasis, infection, tissue repair and autoimmunity, and the role of γδ T cells in malignancy and their potential for novel immunotherapies. Here we discuss a selection of the oral communications at the conference, and summarise exciting new findings in the field regarding the development, mode of antigen recognition, and responses to microorganisms, viruses and tumours by human and mouse γδ T cells.

Background: Extramedullary plasmacytomas (EMP) are rare plasma cell tumors that arise outside the bone marrow. They are most often located in the head and neck region, but may also occur in the other locations. The lower gastrointestinal EMP represents less than 5% of all cases, and location in the anal canal is exceedingly rare. Aim: We present an exceedingly rare case of anal canal plasmacytoma, aiming to achieve a better understanding of this rare entity. Methods: We report a case of a 61-year-old man with a bulky mass in the anal canal. The lesion measured about 6 cm and invaded in all layers of the anal canal wall. The biopsy was performed and revealed a round and plasmocitoid cell population with a solid growth pattern and necrosis. The tumoral cells have express CD79a and CD138 with lambda chains. There was no evidence of disease in other locations and these features were consistent with the diagnosis of an extra-osseous plasmacytoma. The patient was submitted to conformal radiotherapy 50.4 Gy total dose, 1.8 Gy per fraction. After 24 months, the patient is asymptomatic and the lesion has completely disappeared. Conclusions: EMP accounts for approximately 3% of plasma cell malignancies. The median age is about 60 years, and the majority of patients are male. The treatment of choice for extramedullary plasmacytoma is radiation therapy in a dosage of about 50 Gy. Patients should be followed-up for life with repeated bone marrow aspiration and protein studies to detect the development of multiple myeloma.

The molecular characterization of 218 GBS isolates recovered from neonatal invasive infections in Portugal in 2005-2015 revealed the existence of a small number of genetically distinct lineages that were present over a significant time-span. Serotypes III and Ia were dominant in the population, together accounting for >80% of the isolates. Clonal complex 17 included 50% of all isolates, highlighting the importance of the hypervirulent genetic lineage represented by serotype III ST17/rib/PI-1+PI-2b. Serotype Ia was represented mainly by ST23, previously reported as dominant among invasive disease in non-pregnant adults in Portugal, but also by ST24, showing an increased frequency among late-onset disease. Overall erythromycin resistance was 16%, increasing during the study period (p < 0.001). Macrolide resistance was overrepresented among CC1 and CC19 isolates (p < 0.001 and p = 0.008, respectively). While representatives of the hypervirulent CC17 lineage were mostly susceptible to macrolides, we identified for the first time in Europe a recently emerging sublineage characterized by the loss of PI-1 (CC17/PI-2b), simultaneously resistant to macrolides, lincosamides, and tetracycline, also exhibiting high-level resistance to streptomycin and kanamycin. The stability and dominance of CC17 among neonatal invasive infections in the past decades indicates that it is extremely well adapted to its niche; however emerging resistance in this genetic background may have significant implications for the prevention and management of GBS disease.

Este estudo teve por objectivo a análise da dinâmica espaço-temporal dos ecossistemas de sapal da Reserva Natural do Estuário do Sado. O Estuário do Sado é uma das áreas costeiras onde se antevê que as alterações climáticas possam motivar uma subida significativa do nível do mar. Foram seleccionados sectores com uma maior e menor exposição à ondulação lagunar dominante do Estuário do Sado ('lagoon seiche'). A análise de diferentes coberturas de fotografias aéreas e ortofotomapas, entre 1958 e 2007, com recurso a Tecnologias de Informação Geográfica e Geosimulação (Cadeias de Markov e Autómatos Celulares), permitiu a determinação das taxas de erosão e acreção para os sectores abrigados e expostos à ondulação dominante. Procedeu-se ainda à quantificação e à previsão das alterações ao uso e ocupação do solo, com ênfase nos habitats de sapal baixo e alto. Este trabalho demonstrou que a dinâmica de recuo e as alterações de uso e ocupação do solo são dominantes nos ecossistemas de sapal do Estuário do Sado. Apesar do fenómeno de recuo acelerado dos sapais em todo o Estuário do Sado estar correlacionado com a subida do nível do mar, deve ainda ser considerado o efeito induzido pela ocupação antrópica das margens do Estuário. A abordagem desenvolvida poderá assumir um papel relevante na interpretação das dinâmicas espaciais e temporais dos ecossistemas de sapal, e para a simulação da evolução e reacção do território.

Este estudo teve por objectivo a produção de cartografia pormenorizada dos habitats da Rede Natura 2000 do sistema fluviolagunar de Santo André-Monte Velho com recurso a Detecção Remota Multi-espectral sobre Imagens de Satélite de Muito Grande Resolução Espacial (ISMGRE) GeoEye 2011 (GeoEye Foundation). A metodologia adoptada neste estudo baseou-se num estudo de separabilidade espectral e na abordagem combinada (espectral/espacial), tendo sido aplicadas a classificação de imagem ao nível do pixel e a técnica semi-automatizada de Análise de Imagem Baseada em Objectos (OBIA). Com base nos resultados obtidos, ficou comprovado que a integração de Detecção Remota Multi-espectral pode contribuir para a monitorização da área (localização, tamanho), estrutura e função (em particular ao nível das suas características estruturais) dos habitats da Rede Natura 2000. Em termos de exactidão global obtiveram-se valores de 75% para o mapa de habitats produzido. Conclui-se que a Detecção Remota Multi-espectral além de ser de extrema utilidade na monitorização dos habitats da Rede Natura 2000, constitui uma oportunidade emergente para a harmonização de procedimentos metodológicos na produção semi-automática de cartografia de habitats com elevado nível de detalhe em Portugal.

It is now established that natural killer T (NKT) cells can influence adaptive immune responses by producing vast amounts of cytokines. Different subsets of NKT cells with distinctive functional characteristics regarding cytokine production have been described. This is the case for NKT1, NKT2, or NKT17 that resemble conventional CD4 Th1, Th2, and Th17 cells in the cytokines they produce. Unlike conventional CD4 T cells that mostly acquire functional specialization in the periphery, a number of NKT cells become specialized effectors during thymic development. This opinion article describes the evidence for an extrathymic commitment of specialized NKT-cell subsets that, together with thymic lineages, contributes to the overall functional diversity of NKT cells participating in immune responses in the periphery.

The cytokine IL-7 and its receptor, IL-7R, are critical for T cell and, in the mouse, B cell development, as well as differentiation and survival of naive T cells, and generation and maintenance of memory T cells. They are also required for innate lymphoid cell (ILC) development and maintenance, and consequently for generation of lymphoid structures and barrier defense. Here we discuss the central role of IL-7 and IL-7R in the lymphoid system and highlight the impact of their deregulation, placing a particular emphasis on their 'dark side' as promoters of cancer development. We also explore therapeutic implications and opportunities associated with either positive or negative modulation of the IL-7-IL-7R signaling axis.

The potential of cancer immunotherapy relies on the mobilization of immune cells capable of producing antitumour cytokines and effectively killing tumour cells. These are major attributes of γδ T cells, a lymphoid lineage that is often underestimated despite its major role in tumour immune surveillance, which has been established in a variety of preclinical cancer models. This situation notwithstanding, in particular instances the tumour microenvironment seemingly mobilizes γδ T cells with immunosuppressive or tumour-promoting functions, thus emphasizing the importance of regulating γδ T cell responses in order to realize their translation into effective cancer immunotherapies. In this Review we outline both seminal work and recent advances in our understanding of how γδ T cells participate in tumour immunity and how their functions are regulated in experimental models of cancer. We also discuss the current strategies aimed at maximizing the therapeutic potential of human γδ T cells, on the eve of their exploration in cancer clinical trials that may position them as key players in cancer immunotherapy.