RCAAP Repository

Background and objective: Mutations in the MAPT gene cause frontotemporal dementia (FTD). Most previous studies investigating the neuroanatomical signature of MAPT mutations have grouped all different mutations together and shown an association with focal atrophy of the temporal lobe. However, the variability in atrophy patterns between each particular MAPT mutation is less well characterised. We aimed to investigate whether there were distinct groups of MAPT mutation carriers based on their neuroanatomical signature. Methods: We applied Subtype and Stage Inference (SuStaIn), an unsupervised machine learning technique that identifies groups of individuals with distinct progression patterns, to characterise patterns of regional atrophy in MAPT-associated FTD within the Genetic FTD Initiative (GENFI) cohort study. Results: 82 MAPT mutation carriers were analysed, the majority of whom had P301L, IVS10+16 or R406W mutations, along with 48 healthy non-carriers. SuStaIn identified two groups of MAPT mutation carriers with distinct atrophy patterns: a 'temporal' subtype in which atrophy was most prominent in the hippocampus, amygdala, temporal cortex and insula, and a 'frontotemporal' subtype in which atrophy was more localised to the lateral temporal lobe and anterior insula, as well as the orbitofrontal and ventromedial prefrontal cortex and anterior cingulate. There was a one-to-one mapping between IVS10+16 and R406W mutations and the temporal subtype, and a near one-to-one mapping between P301L mutations and the frontotemporal subtype. There were differences in clinical symptoms and neuropsychological test scores between subtypes: the temporal subtype was associated with amnestic symptoms, whereas the frontotemporal subtype was associated with executive dysfunction. Discussion: Our results demonstrate that different MAPT mutations give rise to distinct atrophy patterns and clinical phenotype, providing insights into the underlying disease biology, and potential utility for patient stratification in therapeutic trials.

Background: Core outcome sets (COS) should be relevant to key stakeholders and widely applicable and usable. Ideally, they are developed for international use to allow optimal data synthesis from trials. Electronic Delphi surveys are commonly used to facilitate global participation; however, this has limitations. It is common for these surveys to be conducted in a single language potentially excluding those not fluent in that tongue. The aim of this study is to summarise current approaches for optimising international participation in Delphi studies and make recommendations for future practice. Methods: A comprehensive literature review of current approaches to translating Delphi surveys for COS development was undertaken. A standardised methodology adapted from international guidance derived from 12 major sets of translation guidelines in the field of outcome reporting was developed. As a case study, this was applied to a COS project for surgical trials in gastric cancer to translate a Delphi survey into 7 target languages from regions active in gastric cancer research. Results: Three hundred thirty-two abstracts were screened and four studies addressing COS development in rheumatoid and osteoarthritis, vascular malformations and polypharmacy were eligible for inclusion. There was wide variation in methodological approaches to translation, including the number of forward translations, the inclusion of back translation, the employment of cognitive debriefing and how discrepancies and disagreements were handled. Important considerations were identified during the development of the gastric cancer survey including establishing translation groups, timelines, understanding financial implications, strategies to maximise recruitment and regulatory approvals. The methodological approach to translating the Delphi surveys was easily reproducible by local collaborators and resulted in an additional 637 participants to the 315 recruited to complete the source language survey. Ninety-nine per cent of patients and 97% of healthcare professionals from non-English-speaking regions used translated surveys. Conclusion: Consideration of the issues described will improve planning by other COS developers and can be used to widen international participation from both patients and healthcare professionals.

Wolbachia is one of the most prevalent bacterial endosymbionts, infecting approximately 40% of terrestrial arthropod species. Wolbachia is often a reproductive parasite but can also provide fitness benefits to its host, as, for example, protection against viral pathogens. This protective effect is currently being applied to fight arboviruses transmission by releasing Wolbachia-transinfected mosquitoes. Titre regulation is a crucial aspect of Wolbachia biology. Higher titres can lead to stronger phenotypes and fidelity of transmission but can have a higher cost to the host. Since Wolbachia is maternally transmitted, its fitness depends on host fitness, and, therefore, its cost to the host may be under selection. Understanding how Wolbachia titres are regulated and other aspects of Wolbachia biology has been hampered by the lack of genetic tools. Here we developed a forward genetic screen to identify new Wolbachia over-proliferative mutant variants. We characterized in detail two new mutants, wMelPop2 and wMelOctoless, and show that the amplification or loss of the Octomom genomic region lead to over-proliferation. These results confirm previous data and expand on the complex role of this genomic region in the control of Wolbachia proliferation. Both new mutants shorten the host lifespan and increase antiviral protection. Moreover, we show that Wolbachia proliferation rate in Drosophila melanogaster depends on the interaction between Octomom copy number, the host developmental stage, and temperature. Our analysis also suggests that the life shortening and antiviral protection phenotypes of Wolbachia are dependent on different, but related, properties of the endosymbiont; the rate of proliferation and the titres near the time of infection, respectively. We also demonstrate the feasibility of a novel and unbiased experimental approach to study Wolbachia biology, which could be further adapted to characterize other genetically intractable bacterial endosymbionts.

Background: Uveal melanoma (UM) is the most common intraocular tumor in adults. Despite good primary tumor control, up to 50% of patients develop metastasis, which is lethal. UM often presents asymptomatically and is usually diagnosed by clinical examination and imaging, making it one of the few cancer types diagnosed without a biopsy. Hence, alternative diagnostic tools are needed. Circulating tumor DNA (ctDNA) has shown potential as a liquid biopsy target for cancer screening and monitoring. The aim of this study was to evaluate the feasibility and clinical utility of ctDNA detection in UM using specific UM gene mutations. Methods: We used the highly sensitive digital droplet PCR (ddPCR) assay to quantify UM driver mutations (GNAQ, GNA11, PLCβ4 and CYSTLR2) in cell-free DNA (cfDNA). cfDNA was analyzed in six well established human UM cell lines with known mutational status. cfDNA was analyzed in the blood and aqueous humor of an UM rabbit model and in the blood of patients. Rabbits were inoculated with human UM cells into the suprachoroidal space, and mutated ctDNA was quantified from longitudinal peripheral blood and aqueous humor draws. Blood clinical specimens were obtained from primary UM patients (n = 14), patients presenting with choroidal nevi (n = 16) and healthy individuals (n = 15). Results: The in vitro model validated the specificity and accuracy of ddPCR to detect mutated cfDNA from UM cell supernatant. In the rabbit model, plasma and aqueous humor levels of ctDNA correlated with tumor growth. Notably, the detection of ctDNA preceded clinical detection of the intraocular tumor. In human specimens, while we did not detect any trace of ctDNA in healthy controls, we detected ctDNA in all UM patients. We observed that UM patients had significantly higher levels of ctDNA than patients with nevi, with a strong correlation between ctDNA levels and malignancy. Noteworthy, in patients with nevi, the levels of ctDNA highly correlated with the presence of clinical risk factors. Conclusions: We report, for the first time, compelling evidence from in vitro assays, and in vivo animal model and clinical specimens for the potential of mutated ctDNA as a biomarker of UM progression. These findings pave the way towards the implementation of a liquid biopsy to detect and monitor UM tumors.

Several studies have identified a work environment that promotes inclusiveness as a significant predictor of affiliative organizational citizenship behavior or OCB (such as helping), whereas not much research has focused on inclusion and challenging OCB (i.e., voice). Moreover, no previous studies have explored the above-mentioned relationship in the light of self-determination theory (SDT), given that social exchange theory has traditionally been used as the main explanatory mechanism. Therefore, the aim of the present research was to test the mediating role of basic psychological needs satisfaction in the relationship between inclusion climate, promotive voice and prohibitive voice. Data were collected through self-report questionnaires administered to 246 employees of an international company operating in the service industry. Structural equation modelling was used to analyze the data utilizing R software. Results showed that satisfaction of the needs for autonomy, competence and relatedness partially mediated the relationship between inclusion climate and promotive and prohibitive voice, therefore supporting the idea that social exchange might not be the only determinant for employees to engage in voice behavior. Most importantly, those findings underline how a truly inclusive workplace needs to fulfil its employees’ basic needs of behaving volitionally, feeling effective and connecting meaningfully; this would motivate the workers to voice their suggestions and concerns.

Sectoral contracts in many European countries set minimum wage oors for di erent occupation groups. In addition, employers often pay an extra premium (a wage cushion) to individual workers. We use administrative data from an annual census of employees in Portugal, linked to collective bargaining agreements, to study the interactions between wage oors and wage cushions and assess the impact of wage oors. We show that wages exhibit a \spike" at the wage oor, but that a typical worker receives a 20% premium over the oor, with wide variation across workers and rms. Flexibility of cushions allows mean wages to respond to rm-speci c productivity di erences even within the same sectoral agreement. New contract negotiations tend to raise all wage oors proportionally, with increases that re ect average productivity growth among covered rms. As oors rise, however, wage cushions are eroded, leading to an average passthrough rate of only about one-half. We also nd no evidence of employment responses to oor increases. Finally, we use a series of counterfactual simulations to show that real wage reductions during the recent nancial crisis were facilitated by reductions in real wage oors (-2.2 ppts), reductions in real cushions (-2.5 ppts), and the re-allocation of workers to lower wage oors (-4.8 ppts). O setting these e ects was a rapid rise in share of workers at higher education levels, which in the absence of other factors would have led to rising real wages.

The authors developed a global chronic total occlusion crossing algorithm following 10 steps: 1) dual angiography; 2) careful angiographic review focusing on proximal cap morphology, occlusion segment, distal vessel quality, and collateral circulation; 3) approaching proximal cap ambiguity using intravascular ultrasound, retrograde, and move-the-cap techniques; 4) approaching poor distal vessel quality using the retrograde approach and bifurcation at the distal cap by use of a dual-lumen catheter and intravascular ultrasound; 5) feasibility of retrograde crossing through grafts and septal and epicardial collateral vessels; 6) antegrade wiring strategies; 7) retrograde approach; 8) changing strategy when failing to achieve progress; 9) considering performing an investment procedure if crossing attempts fail; and 10) stopping when reaching high radiation or contrast dose or in case of long procedural time, occurrence of a serious complication, operator and patient fatigue, or lack of expertise or equipment. This algorithm can improve outcomes and expand discussion, research, and collaboration.

O sistema nervoso é responsável pelos processos que tornam a vida humana possível. Permite-nos pensar, sonhar e criar memórias. Controla as nossas acções mais básicas e involuntárias como piscar os olhos, respirar e manter os nossos corações a bater. Os neurónios são as unidades básicas do sistema nervoso, são células notáveis pela especialização para comunicação intercelular que apresentam. Normalmente os neurónios apresentam quatro regiões distintas: o corpo celular, dendrites, axónio e terminais pré-sinápticos. Entre a ponta de cada terminal sináptico e o ponto de contacto no neurónio seguinte há um pequeno espaço chamado sinapse. Cada neurónio pode ligar-se a cerca de 1000 a 10000 outros neurónios. Apesar de muitas destas conexões serem especializadas, todos os neurónios utilizam uma de duas possíveis formas de transmissão sináptica: eléctrica ou química. A força de ambas as formas de transmissão sináptica pode ser aumentada ou diminuída através da actividade celular. Esta plasticidade sináptica é vital para a formação de memórias e para os processos de aprendizagem. Long term potentiation de sinapses químicas é um dos modelos mais estudados para a formação de memórias no cérebro de mamíferos. O sistema nervoso pode ser dividido em duas partes principais: o sistema nervoso central (SNC), que é constituído pelo cérebro e espinal medula, e o sistema nervoso periférico (SNP), que consiste nos nervos craniais e espinais e gânglios associados. O sistema nervoso central pode ser dividido em sete partes: espinal medula, medula, ponte, cerebelo, mesencéfalo, diencéfalo e os hemisférios cerebrais. O córtex prefrontal poderá estar relacionado com a organização da informação interna e externa que é necessária para produzir comportamentos complexos. É a área cerebral que mais espaço ocupa no cérebro humano, e é maior na nossa espécie do que em outros primatas. Este facto poderá ser mais um indício de que o córtex prefrontal está envolvido em algumas capacidades consideradas inteligentes. Está também envolvido no processamento de informação cognitiva e emocional e nos processos de memória de trabalho ou working memory (WM). A working memory é uma memória temporária que é bastante útil no cumprimento de tarefas. O hipocampo é outra zona do cérebro, também muito importante na formação de memória (em especial, memória espacial) e na aprendizagem. As funções do hipocampo podem varar entre espécies, mas a maior parte dos estudos são convergentes, no que respeita a caracterização da anatomia e fisiologia desta área. O hipocampo está ligado ao córtex prefrontal, sendo que esta conexão é feia por axónios que têm origem no subículo e terminam nos neurónios piramidais do PFC. O stress é um aspecto comum nas nossas vidas diárias, mas ainda assim há alguma ambiguidade no que toca à sua definição. É um desafio real ou percepcionado, quer endógeno quer exógeno, que perturba o equilíbrio natural do organismo – homeostase. Os humanos e outros animais respondem a estes desafios desencadeando uma série de mecanismos neuronais, endócrinos, neuro-endócrinos e metabólicos. O impacto do stress no cérebro tem recebida imensa atenção nos últimos anos, tanto da parte de neurologistas como de leigos. De facto, o cérebro é o principal órgão por detrás da resposta ao stress: determina o que é ou não uma ameaça, coordena as reacções que cada um tem, e altera-se, estrutural e funcionalmente como resultado de experiências stressantes. Uma das principais respostas ao stress é a activação do eixo HPA (hipotálamo-pituitária-adrenal). Os danos no córtex prefrontal e no hipocampo em consequência de episódios de stress ou de stress crónico estão bem descritos. Em 2007, Cerqueira demonstrou que a plasticidade sináptica entre o hipocampo e o córtex prefrontal diminui depois de um período de stress crónico e que os efeitos do stress neste circuito são devidos a atrofia neuronal, e não a perda de neurónios. Assim, este trabalho propôs-se a tentar compreender como é que estes efeitos do stress poderão ser revertidos. Para isso, utilizámos ratos Wistar Han como modelo animal, e criámos quatro grupos distintos: animais stressados, animais stressados que foram sujeitos a uma tarefa cognitiva, animais controlo e animais controlo que foram submetidos à mesma tarefa. Posteriormente, avaliámos dois parâmetros em cada grupo: plasticidade sináptica e análise morfológica. Para esse efeito utilizámos um protocolo de electrofisiologia. Um estímulo eléctrico no hipocampo gera uma resposta no córtex prefrontal, e essa resposta pode ser aumentada se for induzido LTP. No entanto esse aumento (ou potenciação do sinal) não é tão elevado em animais stressados, sendo por isso uma boa medida para avaliar se o hole board consegue ou não reverter a perda de plasticidade sináptica neste circuito. A análise morfológica consistiu em reconstruir neurónios em três dimensões, utilizando o software Neurolucida e assim conseguir avaliar a quantidade de dendrites, o seu comprimento, e a densidade de espinhas de cada neurónio estudado. Os nossos resultados demonstram que o treino no hole board foi bem sucedido, já que todos os animais aprenderam a tarefa. No entanto, os animais stressados têm mais dificuldade em aprender a tarefa. No protocolo de electrofisiologia, os resultados foram os esperados, os animais stressados demonstraram menor plasticidade sináptica, enquanto que os animais que fizeram a tarefa cognitiva demonstraram maior plasticidade sináptica, embora o aumento da resposta do prefrontal córtex não fosse tão elevado como nos controlos. Em relação à análise morfológica, os resultados também corresponderam ao esperado. Em praticamente todos os parâmetros foi visível a recuperação dos animais que treinaram no hole board, como por exemplo no número de ramos dendríticos, no seu comprimento ou ate na densidade dendrítica de espinhas. Em conclusão, este estudo demonstrou que uma tarefa cognitiva, neste caso o hole board, pode reverter alguns efeitos do stress, incluindo a perda de plasticidade sináptica e a atrofia neuronal na conexão entre i hipocampo e o córtex prefrontal.

Staphylococcus aureus medical devices related-infections, such as blood stream catheter are of major concern. Their prevention is compulsory and strategies, not prone to the development of resistance, to prevent S. aureus biofilms on catheter surfaces (e.g. silicone) are needed. In this work two different approaches using sophorolipids were studied to prevent S. aureus biofilm formation on medical grade silicone: i) an antiadhesive strategy through covalent bond of sophorolipids to the surface; ii) and a release strategy using isolated most active sophorolipids. Sophorolipids produced by Starmerella bombicola, were characterized by UHPLC-MS and RMN, purified by automatic flash chromatography and tested for their antimicrobial activity towards S. aureus. Highest antimicrobial activity was observed for C18:0 and C18:1 diacetylated lactonic sophorolipids showing a MIC of 50 μg mL-1. Surface modification with acidic or lactonic sophorolipids when evaluating the anti-adhesive or release strategy, respectively, was confirmed by contact angle, FTIR-ATR and AFM analysis. When using a mixture of acidic sophorolipids covalently bonded to silicone surface as antiadhesive strategy cytocompatible surfaces were obtained and a reduction of 90 % on biofilm formation was observed. Nevertheless, if a release strategy is adopted with purified lactonic sophorolipids a higher effect is achieved. Most promising compound was C18:1 diacateylated lactonic sophorolipid that showed no cellular viability reduction when a concentration of 1.5 mg mL-1 was selected and a reduction on biofilm around 5 log units. Results reinforce the applicability of these antimicrobial biosurfactants on preventing biofilms and disclose that their antimicrobial effect is imperative when comparing to their antiadhesive properties.

The phonology of prosody has received little attention in studies of motor speech disorders. The present study investigates the phonology of intonation (nuclear contours) and speech chunking (prosodic phrasing) in Parkinson’s disease (PD) as a function of medication intake and duration of the disease. Following methods of the prosodic and intonational phonology frameworks, we examined the ability of 30 PD patients to use intonation categories and prosodic phrasing structures in ways similar to 20 healthy controls to convey similar meanings. Speech data from PD patients were collected before and after a dopaminomimetic drug intake and were phonologically analyzed in relation to nuclear contours and intonational phrasing. Besides medication, disease duration and the presence of motor fluctuations were also factors included in the analyses. Overall, PD patients showed a decreased ability to use nuclear contours and prosodic phrasing. Medication improved intonation regardless of disease duration but did not help with dysprosodic phrasing. In turn, disease duration and motor fluctuations affected phrasing patterns but had no impact on intonation. Our study demonstrated that the phonology of prosody is impaired in PD, and prosodic categories and structures may be differently affected, with implications for the understanding of PD neurophysiology and therapy.

Sharp force fatalities may have a homicidal, suicidal or accidental manner of death. To aid in such differentiation this study aimed to identify medico-legal elements which were predictors of a given manner of death as well as to describe the characteristics of these deaths. A retrospective review was performed on all homicides and suicides due to sharp force injury admitted at the South Branch of the National Institute of Legal Medicine and Forensic Sciences between January 2012 and December 2019. Deaths with a performed external examination or forensic autopsy and with available demographic, circumstantial or necroscopic information were included. Each case was reviewed to collect said information and inferential analysis was employed with both parametric and non-parametric tests as well as binary logistic regression to identify independent predictors, with significance defined at α = 0.05. A total of 57 homicides and 20 suicides were identified, with the obtained demographic and circumstantial profile of the homicide victim being that of a young foreign male whose body was found outside home, with no weapon nearby and without a known psychiatric background. Homicides presented more prominently stab wounds, with these being conspicuous on the thorax and neck. Conversely suicides notably presented cut wounds, being critically present in the neck and upper limbs. Oblique thoracic stab wounds conveyed a homicidal death. Other findings that suggested homicide included the presence of clothing damage, additional traumatic lesions and injured lungs or bone/cartilage. Toxicologically, alcohol presence was associated with homicides while psychiatric drugs suggested suicide. The logistic regression identified the presence of additional traumatic lesions (OR 14.8, p = 0.032) and the absence of lethal neck (OR 0.109, p = 0.043) and lethal upper limb (OR 0.022, p = 0.015) wounds as independent autopsy predictors of a homicidal death. However, no single feature is infallible in establishing manner of death. To achieve a cogent conclusion, all investigative elements must be considered while attending to the specifics of each case.

Background: Cavotricuspid isthmus (CTI) ablation in typical atrial flutter (AFL) restores sinus rhythm in 95% of patients, which may lead to the discontinuation of oral anticoagulation during follow-up. Therefore, we aimed to systematically review the clinical impact of oral anticoagulation in the incidence of thromboembolic events (TE) after typical AFL ablation. Methods: We searched for controlled studies evaluating the impact of anticoagulation in the incidence of TE in patients submitted to AFL ablation in MEDLINE, CENTRAL, PsycINFO database (June/2021). The primary outcome was TE events (ischemic stroke or systemic embolism). A meta-analysis was performed deriving risk ratios (RR) and 95% confidence intervals (CI). Statistical heterogeneity was measured through I2 metric. The confidence in the evidence was appraised with Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Results: Eight observational studies with 4870 patients were included. TE events were not significantly reduced (RR 1.18, 95% CI 0.59-2.36; n = 4870; GRADE very low). A meta-regression showed that for each 10% increase in the prevalence of previous AF in the studied population, anticoagulation reduced TE risk in 32%. There were no significant differences regarding bleeding events (RR 2.16, 95% CI 0.43-10.97, I2 = 0%; GRADE low), but there was a lower all-cause mortality (RR 0.24, 95% CI 0.17-0.32, GRADE low). Conclusion: The best available evidence lacks robustness and the data did not definitely associate anticoagulation after typical AFL ablation with reduced TE.

Signals from sympathetic neurons and immune cells regulate adipocytes and thereby contribute to fat tissue biology. Interactions between the nervous and immune systems have recently emerged as important regulators of host defence and inflammation1-4. Nevertheless, it is unclear whether neuronal and immune cells co-operate in brain-body axes to orchestrate metabolism and obesity. Here we describe a neuro-mesenchymal unit that controls group 2 innate lymphoid cells (ILC2s), adipose tissue physiology, metabolism and obesity via a brain-adipose circuit. We found that sympathetic nerve terminals act on neighbouring adipose mesenchymal cells via the β2-adrenergic receptor to control the expression of glial-derived neurotrophic factor (GDNF) and the activity of ILC2s in gonadal fat. Accordingly, ILC2-autonomous manipulation of the GDNF receptor machinery led to alterations in ILC2 function, energy expenditure, insulin resistance and propensity to obesity. Retrograde tracing and chemical, surgical and chemogenetic manipulations identified a sympathetic aorticorenal circuit that modulates ILC2s in gonadal fat and connects to higher-order brain areas, including the paraventricular nucleus of the hypothalamus. Our results identify a neuro-mesenchymal unit that translates cues from long-range neuronal circuitry into adipose-resident ILC2 function, thereby shaping host metabolism and obesity.

Esta Newsletter (NL) resulta de uma parceria entre o Instituto de Saúde Baseada na Evidência e a Cochrane Portugal, e tem como objectivo disponibilizar informação sobre áreas interessantes para a prática clínica, com base na melhor evidência científica. São incluídos estudos relevantes, criticamente avaliados pela sua validade, importância dos resultados e aplicabilidade prática, resumidos numa óptica de suporte à decisão. É dada prioridade a estudos de causalidade incluindo-se ainda, quando justificado, estudos qualitativos e metodológicos, assim como revisões científicas. O conteúdo da NL é da exclusiva responsabilidade do(s) seu(s) autor(es).

O cancro do pâncreas é das malignidades mais agressivas e mortais. Esta doença raramente é diagnosticada num estadio em que a resseção cirúrgica é viável. A maioria dos doentes, a quando do diagnóstico, encontram-se num estadio avançado onde as opções terapêuticas são limitadas. Para além disso, as características peculiares do microambiente tumoral do cancro do pâncreas, com um estroma fibrótico extremamente denso, compromete a distribuição eficaz dos fármacos anticancerígenos. A quimioterapia sistémica é a única opção terapêutica para doentes com cancro do pâncreas avançado – FOLFIRINOX ou gemcitabina+nab-paclitaxel. No entanto, ainda não existe na clínica marcadores eficazes com valor preditivo que permitem identificar qual a melhor terapêutica para cada doente. Consequentemente, os doentes são submetidos a múltiplas rondas de tratamento e toxicidades desnecessárias, até encontrar a terapia que seja mais eficaz. A imunoterapia também tem sido explorada como terapia complementar para o tratamento do cancro do pâncreas, incluindo inibidores de checkpoint imunológicos. Contudo, o microambiente tumoral rico em fibroblastos e células imunes com atividade imunossupressora, constitui um obstáculo significativo. Além disso, muitos dos doentes não são elegíveis para este tipo de terapia e portanto estratégias mais personalizadas estão a ser a investigadas em ensaios clínicos. Desta forma, um teste capaz de prever as respostas de cada doente antes do tratamento, seria de grande valor para o tratamento personalizado do cancro do pâncreas. O principal objetivo deste projeto de investigação foi testar as principais opções terapêuticas para o cancro do pâncreas em estadio avançado - FOLFIRINOX e gemcitabina+nab-paclitaxel - utilizando o modelo xenógrafo de peixe-zebra. Com este objetivo, xénografos de peixe-zebra foram gerados utilizando linhas celulares humanas de cancro do pâncreas (Panc-1 e MIA PaCa-2), e várias características tumorais foram analisadas por microscopia confocal, incluindo dinâmica tumoral – proliferação e morte celular – e composição do microambiente tumoral. Os efeitos citotóxicos do nivolumab em monoterapia e em combinação com gemcitabina+nabpaclitaxel (ensaio clínico a decorrer) também foram avaliados. Os resultados demonstraram que as linhas celulares de cancro do pâncreas apresentam diferentes capacidades de implantação no modelo de xénografos de peixe-zebra. Relativamente às terapias anticancerígenas, os nossos resultados demonstraram que os xénografos de peixe-zebra são capazes de revelar respostas tumorais ao FOLFIRINOX e gemcitabina+nab-paclitaxel, incluindo comprometimento da proliferação celular e indução da apoptose. Neste projeto, testámos também a imunoterapia com o anticorpo anti-PD-1- nivolumab. Surpreendentemente os xénografos de peixe-zebra submetidos ao nivolumab em monoterapia e em combinação com gemcitabina+nab-paclitaxel também revelaram sensibilidade celular, com indução significativa da apoptose e redução do tamanho tumoral. De seguida, decidimos caracterizar o microambiente tumoral em particular o infiltrado de neutrófilos e macrófagos. Aos 4 dias pós-injeção, a percentagem de neutrófilos aumentou em relação ao primeiro dia, e os macrófagos do tipo M2 (atividade pró-tumoral) passaram a dominar o microambiente tumoral. Para estudar o papel destes infiltrados na tumorigénese, gerámos xenógrafos em mutantes hipomórficos. A redução de neutrófilos, levou a um aumento do tamanho tumoral, enquanto que a redução de macrófagos, levou a um efeito contrário – diminuição do tamanho tumoral. Estes dados sugerem que os neutrófilos e macrófagos têm um papel antagónico, os neutrófilos com um papel anti-tumoral e os macrófagos pró-tumoral. Sumariamente, os nossos resultados realçam a viabilidade de usar xénografos de peixe-zebra como um modelo in vivo para o screening de respostas tumorais às opções terapêuticas do cancro do pâncreas, e para o estudo da complexidade do microambiente tumoral.

Background: Activin receptor-like kinase 1 (ALK1) is an endothelial transmembrane serine threonine kinase receptor for BMP family ligands that plays a critical role in cardiovascular development and pathology. Loss-of-function mutations in the ALK1 gene cause type 2 hereditary hemorrhagic telangiectasia, a devastating disorder that leads to arteriovenous malformations. Here, we show that ALK1 controls endothelial cell polarization against the direction of blood flow and flow-induced endothelial migration from veins through capillaries into arterioles. Methods: Using Cre lines that recombine in different subsets of arterial, capillary-venous, or endothelial tip cells, we show that capillary-venous Alk1 deletion was sufficient to induce arteriovenous malformation formation in the postnatal retina. Results: ALK1 deletion impaired capillary-venous endothelial cell polarization against the direction of blood flow in vivo and in vitro. Mechanistically, ALK1-deficient cells exhibited increased integrin signaling interaction with vascular endothelial growth factor receptor 2, which enhanced downstream YAP/TAZ nuclear translocation. Pharmacologic inhibition of integrin or YAP/TAZ signaling rescued flow migration coupling and prevented vascular malformations in Alk1-deficient mice. Conclusions: Our study reveals ALK1 as an essential driver of flow-induced endothelial cell migration and identifies loss of flow-migration coupling as a driver of arteriovenous malformation formation in hereditary hemorrhagic telangiectasia disease. Integrin-YAP/TAZ signaling blockers are new potential targets to prevent vascular malformations in patients with hereditary hemorrhagic telangiectasia.

HER2 is a prognostic and predictive biomarker in breast cancer, normally assessed in tumour biopsy and used to guide treatment choices. Circulating tumour cells (CTCs) escape the primary tumour and enter the bloodstream, exhibiting great metastatic potential and representing a real-time snapshot of the tumour burden. Liquid biopsy offers the unique opportunity for low invasive sampling in cancer patients and holds the potential to provide valuable information for the clinical management of cancer patients. This study assesses the performance of the RUBYchip™, a microfluidic system for CTC capture based on cell size and deformability, and compares it with the only FDA-approved technology for CTC enumeration, CellSearch®. After optimising device performance, 30 whole blood samples from metastatic breast cancer patients were processed with both technologies. The expression of HER2 was assessed in isolated CTCs and compared to tissue biopsy. Results show that the RUBYchipTM was able to isolate CTCs with higher efficiency than CellSearch®, up to 10 times more, averaging all samples. An accurate evaluation of different CTC subpopulations, including HER2+ CTCs, was provided. Liquid biopsy through the use of the RUBYchipTM in the clinic can overcome the limitations of histological testing and evaluate HER2 status in patients in real-time, helping to tailor treatment during disease evolution.

Heart failure (HF) is a major health problem with a significant impact on morbidity, mortality, quality of life and healthcare costs. Despite the positive impact of disease-modifying therapies developed over the last four decades, HF mortality and hospitalization remain high. We aim at reviewing the evidence supporting the use of sodium-glucose co-transporter-2 (SGLT-2) inhibitors, as a novel strategy for HF with reduced ejection fraction (HFrEF) treatment. The consistent observation of a reduction in HF hospitalizations in type-2 diabetes cardiovascular safety trials EMPA-REG OUTCOME, CANVAS, DECLARE-TIMI 58 and VERTIS raised the hypothesis that SGLT-2 inhibitors could have an impact in HF treatment. This hypothesis was first confirmed in 2019 with the DAPA-HF publication showing that dapagliflozin on top of optimized HFrEF therapy, reduced HF-hospitalizations and cardiovascular mortality. This was reinforced by the EMPEROR-Reduced publication in 2020 showing that empagliflozin on top of optimized HFrEF therapy, reduced HF-hospitalizations. Both studies established SGLT-2 inhibitors as a fourth pillar of HFrEF prognosis-modifying therapy, in addition to the gold standard triple neurohormonal modulation/blockade.

A temática da qualidade de vida no trabalho e a satisfação profissional tem assumido um papel cada vez mais relevante no mundo das organizações e na psicologia dos recursos humanos. A presente investigação tem como objectivo central comparar a qualidade de vida no trabalho e a satisfação profissional entre teletrabalhadores e trabalhadores tradicionais, que são profissionais da tecnologia da informação. Para avaliar a qualidade de vida no trabalho foi aplicado o instrumento designado de Inventário sobre a Qualidade de Vida no Trabalho (Rafael & Lima, 2007a, 2008a) e indicadores de Satisfação Profissional. A amostra é constituída por 51 profissionais empregados, teletrabalhadores e trabalhadores tradicionais. Os resultados obtidos revelam que os teletrabalhadores apresentam um nível mais elevado de QVT em geral, comparativamente com os trabalhadores tradicionais. Da mesma maneira, verifica-se que existem níveis de SP mais elevados nos teletrabalhadores por comparação aos trabalhadores tradicionais.

Influenza viruses are major human pathogens, responsible for respiratory diseases affecting millions of people worldwide, with high morbidity and significant mortality. Infections by influenza can be controlled by vaccines and antiviral drugs. However, this virus is constantly under mutations, limiting the effectiveness of these clinical antiviral strategies. It is therefore urgent to develop new ones. Influenza hemagglutinin (HA) is involved in receptor binding and promotes the pH-dependent fusion of viral and cell endocytic membranes. HA-targeted peptides may emerge as a novel antiviral option to block this viral entry step. In this study, we evaluated three HA-derived (lipo)peptides using fluorescence spectroscopy. Peptide membrane interaction assays were performed at neutral and acidic pH to better resemble the natural conditions in which influenza fusion occurs. We found that peptide affinity towards membranes decreases upon the acidification of the environment. Therefore, the released peptides would be able to bind their complementary domain and interfere with the six-helix bundle formation necessary for viral fusion, and thus for the infection of the target cell. Our results provide new insight into molecular interactions between HA-derived peptides and cell membranes, which may contribute to the development of new influenza virus inhibitors.