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Humans have been altering the Mediterranean landscapes for millennia. To diminish the probability of encounters with domestic animals, humans and their activities, many species adjust their behavior to become more nocturnal. Even habitat-generalist species, such as red fox and stone marten that are somehow tolerant to environmental changes, might be affected by anthropic disturbances. Nevertheless, only a small number of studies were implemented in Iberia targeting these mesocarnivores’ activity patterns, and fewer have assessed the temporal ecology of these species in Eucalyptus plantations, the current main forest cover in Portugal. Based on camera traps, we aimed to analyze: 1) the temporal and spatio-temporal activity patterns of red fox and stone marten; and 2) how they are affected by distinct human disturbances (i.e., humans, livestock, dogs, plantations, and hunting). Foxes presented a higher crepuscular activity, while martens were entirely nocturnal, suggesting some avoidance behavior. Both mesocarnivores showed a higher overlap with dogs’ activity than with humans or livestock. Foxes’ activity patterns vary between seasons and habitats but were not influenced by the hunting period. Results suggest that both mesocarnivores, besides setting apart their activity from humans related disturbances, also show a tendency to temporally avoid each other. While the increase of nocturnality may indicate an anthropic disturbance impact, a reduction of activity overlap between mesocarnivores may be a strategy to reduce competition. These results may help support the sustainable management of landscapes by highlighting critical periods where activity overlaps may occur, and thus the anthropic impacts on wildlife are higher.

Early life stress can have significant effects on the developing brain and lead to changes in the structure and function of brain regions involved in stress regulation, emotion and cognitive control. Here, we used the social instability stress (SIS) protocol to understand the impact of social stress during mild (PND30) and late (PND45) adolescence. Our results revealed that SIS can compromise the dominance-subordination coping strategy but does not affect social recognition and motivation in rats. Moreover, SIS can lead to subtle modifications at the molecular level that hamper normal development of the prefrontal cortex in a sex- and age-dependent manner. Understanding the impact of early life stress on brain organization is crucial for developing effective prevention and intervention strategies. By identifying those who are most vulnerable to the effects of stress and providing targeted support and resources, it may be possible to mitigate the negative consequences of early adversity and promote healthy brain development.

Gastric cancer is a dominating cause of cancer-associated mortality with limited therapeutic options. Here, we show that syndecan-4 (SDC4), a transmembrane proteoglycan, is highly expressed in intestinal subtype gastric tumors and that this signature associates with patient poor survival. Further, we mechanistically demonstrate that SDC4 is a master regulator of gastric cancer cell motility and invasion. We also find that SDC4 decorated with heparan sulfate is efficiently sorted in extracellular vesicles (EVs). Interestingly, SDC4 in EVs regulates gastric cancer cell-derived EV organ distribution, uptake, and functional effects in recipient cells. Specifically, we show that SDC4 knockout disrupts the tropism of EVs for the common gastric cancer metastatic sites. Our findings set the basis for the molecular implications of SDC4 expression in gastric cancer cells and provide broader perspectives on the development of therapeutic strategies targeting the glycan-EV axis to limit tumor progression.

Humans have negatively impacted most ecosystems on Earth, altering how species use habitats and resources available to them, but also their circadian rhythms. Among many factors affecting animal activity patterns, conversion of native habitat into production forests and hunting are critical, and their impacts may be exacerbated by seasonal weather conditions. Both these factors are issues in Mediterranean Europe, especially in Portugal. Nevertheless, their impact on native species behavior remains largely unknown, even for generalist species often resilient to human disturbance such as wild boar (Sus scrofa). Therefore, we assessed temporal activity patterns of wild boar in Portugal to explore differences between habitats (native forest versus Eucalyptus plantations), hunting and non-hunting periods, or between seasons. We found that wild boars were primarily nocturnal, with greater nighttime activity more evident during the dry season and within plantations. Furthermore, they appeared to avoid dusk during the hunting season. Together, these patterns indicate that even a species typically resilient to disturbance and environmental change, such as wild boar, tends to avoid adverse weather conditions and disturbance factors, namely high daytime temperatures in summer and probability of encountering forestry workers or hunters. Accordingly, other more sensitive or resource-demanding mammals may also be affected, so evaluating the impacts of the studied anthropic drivers on other mammals should be prioritized to provide information for sustainable plantation management and hunting.

Eucalyptus plantations, the second most economically important exotic tree in Europe, cover circa 1,5 million hectares on this continent. However, little is known about their effect on the ecological patterns of widely distributed and increasing populations of wild ungulates. This lack of knowledge jeopardizes our ability to correctly manage these populations in increasingly ubiquitous exotic forests. We aimed to understand how exotic forestry plantations influence ungulates spatial and temporal dimensions of their niche and determine how the species interactions may be changed by these artificial systems. We used roe deer and red deer as wildlife models, the Portuguese Eucalyptus plantation as standards for forestry plantations, and camera-trapping, occupancy modeling, and kernel density estimators as tools to fulfill our goals. Eucalyptus plantations had a strong effect on roe deer and red deer spatial behavior when compared to areas dominated by native vegetation. Both species seem to avoid disturbed areas such as agricultural land and Eucalyptus plantations. Even when using plantations, they shift their activity to reduce human encounters. Furthermore, plantations are not a homogeneous landcover, and thus distinct production phases of Eucalyptus plantations affect species interactions and activity patterns differently. Our results show that the pre-harvesting phases seem to be the more critical period for deer. Thus, production forest managers must guarantee that plantation structure encompasses areas with different tree ages to minimize this effect and fulfill deer’s food and cover requirements. Forestry activities should avoid dawn and dusk, to minimize disturbance and to reduce the negative interaction between sympatric guild members, by allowing species to be sparsely distributed (and not clustered in the few undisturbed patches). Plantations should include dispersed native patches to which animals may move in search of food and refuge, therefore creating discontinuities within plantations.

Methamphetamine (Meth) is a powerful illicit psychostimulant, widely used for recreational purposes. Besides disrupting the monoaminergic system and promoting oxidative brain damage, Meth also causes neuroinflammation, contributing to synaptic dysfunction and behavioral deficits. Aberrant activation of microglia, the largest myeloid cell population in the brain, is a common feature in neurological disorders triggered by neuroinflammation. In this study, we investigated the mechanisms underlying the aberrant activation of microglia elicited by Meth in the adult mouse brain. We found that binge Meth exposure caused microgliosis and disrupted risk assessment behavior (a feature that usually occurs in individuals who abuse Meth), both of which required astrocyte-to-microglia crosstalk. Mechanistically, Meth triggered a detrimental increase of glutamate exocytosis from astrocytes (in a process dependent on TNF production and calcium mobilization), promoting microglial expansion and reactivity. Ablating TNF production, or suppressing astrocytic calcium mobilization, prevented Meth-elicited microglia reactivity and re-established risk assessment behavior as tested by elevated plus maze (EPM). Overall, our data indicate that glial crosstalk is critical to relay alterations caused by acute Meth exposure. This work was financed by FEDER—Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT— Fundação para a Ciência e a Tecnologia/Ministério da Ciência (FCT), Tecnologia e Ensino Superior in the framework of the project POCI-01-0145-FEDER-030647 (PTDC/ SAU-TOX/30647/2017) in TS lab. FEDER Portugal (Norte-01-0145-FEDER000008000008—Porto Neurosciences and Neurologic Disease Research Initiative at I3S, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); FCOMP-01-0124-FEDER-021333). CCP and RS hold employment contracts financed by national funds through FCT –in the context of the program-contract described in paragraphs 4, 5, and 6 of art. 23 of Law no. 57/ 2016, of August 29, as amended by Law no. 57/2017 of July 2019. TC, TOA, AFT, JB, AIS and AM were supported by FCT (SFRH/BD/117148/2016, SFRH/BD/147981/2019, 2020.07188.BD, PD/BD/135450/2017, SFRH/BD/144324/2019, and IF/00753/2014). Work in JBR lab was supported by the FCT project PTDC/ MED-NEU/31318/2017. JFO was also supported by FCT projects PTDC/MED-NEU/31417/2017 and POCI-01- 0145-FEDER-016818; Bial Foundation Grants 207/14 and 037/18, by National funds, through FCT - project UIDB/50026/2020; and by the projects NORTE-01-0145-FEDER000013 and NORTE-01-0145-FEDER-000023, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). Funding of i3S Scientific Platforms: Advanced Light Microscopy (ALM), a member of the national infrastructure PPBI-Portuguese Platform of BioImaging (POCI-01–0145-FEDER022122); and Genomics through GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020—Operational Programme for Competitiveness and Internationalization (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by FCT.

Forestry plantations have increased considerably over recent decades to fulfil human demand for wood, pulp and paper. Eucalyptus globulus Labill is one of the most abundant plantation species, particularly in Europe, where its largest presence is in Portugal. Furthermore, plantations in Mediterranean areas, such as Portugal, frequently suffer from forest fires, and thus it is crucial to understand their impacts on vertebrates. This is especially relevant for some species, like small mammals, that use landscapes at smaller scales for which even small changes in forest cover may have a profound effect. In this study, we evaluate the effects of several environmental, disturbance and habitat drivers on the relative abundance of rodents (Muridae) in Eucalyptus plantations in central Portugal. Specimen capture took place across two seasons and at eight study sites representing six different stages of Eucalyptus plantations and two native forests from 2019 to 2020. Using a structural equation modelling approach, we show that the relative abundance of rodents was promoted by recent wildfire events and was higher in areas where carnivores and wild boar were more abundant. By contrast, abundant deer and increased percentages of herbaceous or litter cover and bare soil limited the abundance of rodents. We did not detect a significant relationship between Eucalyptus plantations and the relative abundance of rodents. The presence of other species, either by direct contact (carnivores) or by inducing habitat changes (ungulates), and vegetation structure, likely linked to plantation management or fire regime, are the more important factors dictating the population dynamics of rodents across plantation forests in central Portugal.

Purpose The purpose of this paper is to develop new boundary conditions for simulating the injection molding process of polymer melts. Design/methodology/approach The boundary conditions are derived and implemented to simulate real-life air vents (used to allow the air escape from the mold). The simulations are performed in the computational libraryOpenFOAM (R) by considering two different fluid models, namely, Newtonian and generalized Newtonian (Bird-Carreau model). Findings A detailed study on the accuracy of the solverinterFoamfor simulating the filling stage is presented, by considering simple geometries and adaptive mesh refinement. The verified code is then used to study the three-dimensional filling of a more complex geometry. Originality/value The results obtained showed that the numerical method is stable and allows one to model the filling process, simulating the real injection molding process., This work is funded by FEDER funds through the COMPETE 2020 Programme and National Funds through FCT (Portuguese Foundation for Science and Technology) under the projects UID-B/05256/2020, UID-P/05256/2020 and MOLDPRO-Aproximacoes multi-escala para moldacao por injecao de materiais plasticos (POCI-01-0145-FEDER-016665).The research of L.L. Ferras was partially financed by the Portuguese Funds through FCT within the Projects UID-B/00013/2020, UID-P/00013/2020 and the scholarship SFRH/BPD/100353/2014.The authors would like to acknowledge the Minho University Cluster (NORTE-07-0162-FEDER-000086) for providing the HPC resources that contributed to the research results reported within this paper.

Analysis of rodents’ behavior/activity is of fundamental importance in many research fields. However, many behavioral experiments still rely on manual scoring, with obvious problems in reproducibility. Despite important advances in video-analysis systems and computational ethology, automated behavior quantification is still a challenge. The need for large training datasets, background stability requirements, and reduction to two-dimensional analysis (impairing full posture characterization), limit their use. Here we present a novel integrated solution for behavioral analysis of individual rats, combining video segmentation, tracking of body parts, and automated classification of behaviors, using machine learning and computer vision methods. Low-cost depth cameras (RGB-D) are used to enable three-dimensional tracking and classification in dark conditions and absence of color contrast. Our solution automatically tracks five anatomical landmarks in dynamic environments and recognizes seven distinct behaviors, within the accuracy range of human annotations. The developed free software was validated in experiments where behavioral differences between Wistar Kyoto and Wistar rats were automatically quantified. The results reveal the capability for effective automated phenotyping. An extended annotated RGB-D dataset is also made publicly available. The proposed solution is an easy-to-use tool, with low-cost setup and powerful 3D segmentation methods (in static/dynamic environments). The ability to work in dark conditions means that natural animal behavior is not affected by recording lights. Furthermore, automated classification is possible with only ~30 minutes of annotated videos. By creating conditions for high-throughput analysis and reproducible quantitative measurements of animal behavior experiments, we believe this contribution can greatly improve behavioral analysis research.

Internship Report presented as the partial requirement for obtaining a Master's degree in Information Management, specialization in Knowledge Management and Business Intelligence As IT Consulting market revenue increases year after year, more and more digital transformation projects are being sold. Yet, the deep change IT consultants sell to their clients in this type of projects, which translates into the digitalisation of practices accompanied by a change in mentalities, is not usually the reality that we find in their same consultancy firms. For Creative Management, the company that hosted the internship, the problem recurs: there is a general desire of evolving into a digital company, with some disconnected digital tools already implemented but without planning or coordination. Literature shows that a Digital Transformations requires several premises to develop into a successful project such as the definition of a plan, the knowledge and support of leaders, investment, etc. My project, within the internship, aimed to address Digital Transformation at Creative Management by coordinating an internal digital strategy that materialized in new technological tools. The key takeaway is the fact that an IT Consulting firm is probably better prepared for this type of change than non-IT consultancies.

We present a case of a 33-year-old male who worked as a plumber and a locksmith. The patient presented with diffuse myalgia and asthenia, skin sclerosis and puffy fingers, Raynaud's phenomenon, exertional dyspnea and erectile dysfunction. The presence of specific autoantibodies enabled the diagnosis of systemic sclerosis. Chest-computed tomography revealed upper lobe consolidation. After extensive evaluation, the multidisciplinary interstitial lung disease team concluded that the patient also had advanced silicosis. After a year, there was significant clinical, radiologic, and functional deterioration of the lung disease. The patient was referred for lung transplant. Silica inhalation is the cause of silicosis but is also implicated in the development of systemic sclerosis (Erasmus syndrome). Although they share a common risk factor, it is rare to find both diseases co-existing. We present this case of a young patient where both diseases presented aggressively in order to raise awareness to this association. Apresentamos o caso de um homem de 33 anos que trabalhava como canalizador e serralheiro. Apresentava mialgias e astenia, esclerose cutânea e puffy fingers, fenómeno de Raynaud, dispneia de esforço e disfunção erétil. A presença de autoanticorpos específicos permitiu o diagnóstico de esclerose sistémica. A tomografia computadorizada de tórax revelou consolidações dos lobos superiores. Após extensa avaliação, o grupo multidisciplinar de doenças do interstício concluiu que o doente tinha também silicose avançada. Após um ano, houve agravamento clínico, radiológico e funcional significativo da doença pulmonar. O doente foi encaminhado para transplante pulmonar. A inalação de sílica é a causa da silicose, mas também está implicada no desenvolvimento da esclerose sistémica (síndrome de Erasmus). Embora tenham um fator de risco comum, é raro encontrar as duas doenças simultaneamente. Apresentamos o caso de um doente jovem em que ambas as doenças se apresentaram de forma agressiva para alertar sobre esta associação. info:eu-repo/semantics/publishedVersion

Helicobacter pylori infects half of the world population, being associated with several gastric disorders, such as chronic gastritis and gastric carcinoma. The Helicobacter genus also includes other gastric helicobacters, such as H. heilmannii¸ H. ailurogastricus, H. suis, H. felis, H. bizzozeronii, and H. salomonis. These gastric helicobacters colonize both the human and animal stomach. The prevalence of gastric non-Helicobacter pylori Helicobacter (NHPH) species in humans has been described as low, and the in vitro binding to the human gastric mucosa was never assessed. Herein, human gastric tissue sections were used for the evaluation of the tissue glycophenotype and for the binding of gastric NHPH strains belonging to different species. Histopathological evaluation showed that 37.5% of the patients enrolled in our cohort presented chronic gastritis, while the presence of neutrophil or eosinophilic activity (chronic active gastritis) was observed in 62.5% of the patients. The secretor phenotype was observed in 68.8% of the individuals, based on the expression of Lewis B antigen and binding of the UleX lectin. The in vitro binding assay showed that all the NHPH strains evaluated were able to bind, albeit in low frequency, to the human gastric mucosa. The H. heilmannii, H. bizzozeronii, and H. salomonis strains displayed the highest binding ability both to the gastric superficial epithelium and to the deep glands. Interestingly, we observed binding of NHPH to the gastric mucosa of individuals with severe chronic inflammation and intestinal metaplasia, suggesting that NHPH binding may not be restricted to the healthy gastric mucosa or slight chronic gastritis. Furthermore, the in vitro binding of NHPH strains was observed both in secretor and non-secretor individuals in a similar frequency. In conclusion, this study is the first report of the in vitro binding ability of gastric NHPH species to the human gastric mucosa. The results suggest that other glycans, besides the Lewis antigens, could be involved in the bacterial adhesion mechanism; however, the molecular intervenients remain unknown.

Microglial homeostatic functions are fundamental to regulate the central nervous system microenvironment. We use conditional cell-specific gene targeting, RNA-seq profiling, high-throughput proteomics, phosphoproteomics, systems biology, and animal behavior to report a critical role for the RhoGTPase Rac1 in regulating adult microglia physiology. Ablation of Rac1 in adult microglia impaired their ability to sense and interpret the brain microenvironment and affected their capacity to communicate with synapses to drive cognitive performance, both at the steady-state and during experience-dependent plasticity. Overall, our results reveal a novel and central role for Rac1 as a regulator of microglia homeostasis and a molecular driver of the microglia-synapse crosstalk required for context-dependent sociability and learning related to memory.

Heparan sulfate (HS) proteoglycans (HSPGs) are abundant glycoconjugates in cells' glycocalyx and extracellular matrix. By acting as scaffolds for protein-protein interactions, HSPGs modulate extracellular ligand gradients, cell signaling networks, and cell-extracellular matrix crosstalk. Aberrant expression of HSPGs and enzymes involved in HSPG biosynthesis and processing has been reported in tumors, with impact in cancer cell behavior and tumor microenvironment properties. However, the roles of specific glycosyltransferases in the deregulated biosynthesis of HSPGs are not fully understood. In this study, we established glycoengineered gastric cancer cell models lacking either exostosin-like glycosyltransferase 2 (EXTL2) or EXTL3 and revealed their regulatory roles in both HS and chondroitin sulfate (CS) biosynthesis and structural features. We showed that EXTL3 is key for initiating the synthesis of HS chains in detriment of CS biosynthesis, intervening in the fine-tuned balance of the HS/CS ratio in cells, while EXTL2 functions as a negative regulator of HS biosynthesis, with impact over the glycoproteome of gastric cancer cells. We demonstrated that KO of EXTL2 enhanced HS levels along with concomitant upregulation of Syndecan-4, which is a major cell surface carrier of HS. This aberrant HS expression profile promoted a more aggressive phenotype, characterized by higher cellular motility and invasion, and impaired activation of Ephrin type-A 4 cell surface receptor tyrosine kinase. Our findings uncover the biosynthetic roles of EXTL2 and EXTL3 in the regulation of cancer cell GAGosylation and proteoglycans expression and unravel the functional consequences of aberrant HS/CS balance in cellular malignant features.

Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n=31,573) has the highest number of records followed by Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496), Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n=12,159], Monachus monachus [n=1,512], and Lynx pardinus [n=197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications.

Prosocial behavior in rats is known to occur in response to a familiar rat's distress, but the motivations underlying prosocial behavior remain elusive. In this study, we adapted the experimental setting of Ben-Ami Bartal, Decety, and Mason (2011) to explore different motivations behind helping behavior in adolescent rats. In the original setting, a free rat is placed in an arena where a cagemate is trapped inside a restrainer that can only be opened from the outside by the free rat. Here we added a dark compartment to the experimental setting that allowed the free rat to escape the arena and the distress evoked by the trapped cagemate, based on rodents' aversion to bright areas. As a control, we tested rats in the same arena but with the door to the dark area closed. Our results showed that all free rats, except one in the escape condition, learned to open the restrainer's door. However, in the escape condition, rats took significantly longer to open the restrainer to the cagemates when compared with rats that could not escape. To further explore the motivations underlying these group differences in door-opening latencies, we measured both rats' behavior. We found that struggling behavior (i.e., distress) in the trapped rat did not affect door-opening, whereas exploratory behavior (i.e., proactive/positive behavior) in both rats contributed to shorter times. Our results highlight that adolescent rats show prosocial behavior even when they can escape without helping and contribute to demonstrate the role of positive emotional states in prosocial behavior., This research project was financed by Fundacao para a Ciencia e Tecnologia (FCT) and Orcamento do Estado in the framework of the project IF/00753/2014/CP1241/CT0005 at Institute for Research and Innovation in Health Sciences and by European Regional Development Fund (FEDER) funds through Programa Operacional Factores de Competitividade-COMPETE and by Portuguese funds through FCT, in the framework of the project PTDC/MHCPAP/5304/2012 awarded to Instituto de Ciencias Biomedias de Abel Salazar at University of Porto. Part of this study was conducted at Psychology Research Centre (PSI/01662), University of Minho, supported by FCT and the Portuguese Ministry of Science, Technology and Higher Education through national funds, and cofinanced by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653). Ana Magalhaes was supported by FCT (IF/00753/2014). Joana Carvalheiro holds an FCT fellowship (PD/BD/128467/2017). Ana Seara-Cardoso was supported by FCT (SFRH/BPD/94970/2013). Ana Raquel Mesquita was supported by FCT (IF/00750/2015). Teresa Summavielle was supported by FCT (IF/00875/2012).

Methylphenidate (MPH) is the classic treatment for attention deficit hyperactivity disorder (ADHD) among children and adults. Despite its beneficial effects, non-medical use of MPH is nowadays a problem with high impact on society. Thus, our goal was to uncover the neurovascular and cognitive effects of MPH chronic use during a critical period of development in control conditions. For that, male Wistar Kyoto rats were treated with MPH (1.5 or 5 mg/kg/day at weekdays, per os) from P28 to P55. We concluded that the higher dose of MPH caused hippocampal blood-brain barrier (BBB) hyperpermeability by vesicular transport (transcytosis) concomitantly with the presence of peripheral immune cells in the brain parenchyma. These observations were confirmed by in vitro studies, in which the knockdown of caveolin-1 in human brain endothelial cells prevented the increased permeability and leukocytes transmigration triggered by MPH (100 µM, 24 h). Furthermore, MPH led to astrocytic atrophy and to a decrease in the levels of several synaptic proteins and impairment of AKT/CREB signaling, together with working memory deficit assessed in the Y-maze test. On the contrary, we verified that the lower dose of MPH (1.5 mg/kg/day) increased astrocytic processes and upregulated several neuronal proteins as well as signaling pathways involved in synaptic plasticity culminating in working memory improvement. In conclusion, the present study reveals that a lower dose of MPH in normal rats improves memory performance being associated with the modulation of astrocytic morphology and synaptic machinery. However, a higher dose of MPH leads to BBB dysfunction and memory impairment.

Background: Changes in glycosylation are known to play critical roles during gastric carcinogenesis. Expression of truncated O-glycans, such as the Sialyl-Tn (STn) antigen, is a common feature shared by many cancers and is associated with cancer aggressiveness and poor-prognosis. Methods: Glycoengineered cell lines were used to evaluate the impact of truncated O-glycans in cancer cell biology using in vitro functional assays, transcriptomic analysis and in vivo models. Tumor patients ‘samples and datasets were used for clinical translational significance evaluation. Findings: In the present study, we demonstrated that gastric cancer cells expressing truncated O-glycans display major phenotypic alterations associated with higher cell motility and cell invasion. Noteworthy, the glycoengineered cancer cells overexpressing STn resulted in tumor xenografts with less cohesive features which had a critical impact on mice survival. Furthermore, truncation of O-glycans induced activation of EGFR and ErbB2 receptors and a transcriptomic signature switch of gastric cancer cells. The disclosed top activated genes were further validated in gastric tumors, revealing that SRPX2 and RUNX1 are concomitantly overexpressed in gastric carcinomas and its expression is associated with patients’ poor-survival, highlighting their prognosis potential in clinical practice. Interpretation: This study discloses novel molecular links between O-glycans truncation frequently observed in cancer and key cellular regulators with major impact in tumor progression and patients’ clinical outcome. This work was funded by FEDER funds through the Operational Programme for Competitiveness Factors-COMPETE ( POCI-01-0145-FEDER-016585 ; POCI-01-0145-FEDER-007274 ; POCI-01-0145-FEDER-028489 ) and National Funds through the Foundation for Science and Technology (FCT) , under the projects: PTDC/BBB-EBI/0567/2014 (to CAR), PTDC/MED-ONC/28489/2017 (to AM) and UID/BIM/04293/2013 ; and the project NORTE-01-0145-FEDER-000029 , supported by Norte Portugal Regional Programme ( NORTE 2020 ), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). The authors acknowledge the support by Gastric Glyco Explorer Initial Training Network (European Union Seventh Framework Programme GastricGlycoExplorer project, grant number 316929 ). DF acknowledges the FCT PhD Programmes and Programa Operacional Potencial Humano (POPH), specifically the BiotechHealth Programe (Doctoral Programme on Cellular and Molecular Biotechnology Applied to Health Sciences), with the reference PD/0016/2012 funded by FCT . Grants were received from FCT, POPH and FSE (Fundo Social Europeu): SFRH/BD/110636/2015 to DF and SFRH/BPD/115730/2016 to FP. We thank Catharina Steentoft and Henrik Clausen for the cell line models and helpful scientific discussions. We are grateful for Nuno Mendes's technical support. The authors acknowledge the support of José Luis Costa and Mafalda Rocha from the i3S Genomics Platform (GenCore), and Maria G Lazaro from the Bioimaging I3S Scientific Platform , member of the PPBI ( PPBI-POCI-01-0145-FEDER-022122 ).