Dissecting genetics of spectrum of epilepsies with eyelid myoclonia by exome sequencing.

OBJECTIVE: Epilepsy with eyelid myoclonia (EEM) spectrum is a generalized form of epilepsy characterized by eyelid myoclonia with or without absences, eye closure-induced seizures with electroencephalographic paroxysms, and photosensitivity. Based on the specific clinical features, age at onset, and familial occurrence, a genetic cause has been postulated. Pathogenic variants in CHD2, SYNGAP1, NEXMIF, RORB, and GABRA1 have been reported in individuals with photosensitivity and eyelid myoclonia, but whether other genes are also involved, or a single gene is uniquely linked with EEM, or its subtypes, is not yet known. We aimed to dissect the genetic etiology of EEM. METHODS: We studied a cohort of 105 individuals by using whole exome sequencing. Individuals were divided into two groups: EEM- (isolated EEM) and EEM+ (EEM accompanied by intellectual disability [ID] or any other neurodevelopmental/psychiatric disorder). RESULTS: We identified nine variants classified as pathogenic/likely pathogenic in the entire cohort (8.57%); among these, eight (five in CHD2, one in NEXMIF, one in SYNGAP1, and one in TRIM8) were found in the EEM+ subcohort (28.57%). Only one variant (IFIH1) was found in the EEM- subcohort (1.29%); however, because the phenotype of the proband did not fit with published data, additional evidence is needed before considering IFIH1 variants and EEM- an established association. Burden analysis did not identify any single burdened gene or gene set. SIGNIFICANCE: Our results suggest that for EEM, as for many other epilepsies, the identification of a genetic cause is more likely with comorbid ID and/or other neurodevelopmental disorders. Pathogenic variants were mostly found in CHD2, and the association of CHD2 with EEM+ can now be considered a reasonable gene-disease association. We provide further evidence to strengthen the association of EEM+ with NEXMIF and SYNGAP1. Possible new associations between EEM+ and TRIM8, and EEM- and IFIH1, are also reported. Although we provide robust evidence for gene variants associated with EEM+, the core genetic etiology of EEM- remains to be elucidated.

Bipolar-associated miR-499-5p controls neuroplasticity by downregulating the Cav1.2 subunit CACNB2.

Bipolar disorder (BD) is a chronic mood disorder characterized by manic and depressive episodes. Dysregulation of neuroplasticity and calcium homeostasis are frequently observed in BD patients, but the underlying molecular mechanisms are largely unknown. Here, we show that miR-499-5p regulates dendritogenesis and cognitive function by downregulating the BD risk gene CACNB2. miR-499-5p expression is increased in peripheral blood of BD patients, as well as in the hippocampus of rats which underwent juvenile social isolation. In rat hippocampal neurons, miR-499-5p impairs dendritogenesis and reduces surface expression and activity of the L-type calcium channel Cav1.2. We further identified CACNB2, which encodes a regulatory ß-subunit of Cav1.2, as a direct functional target of miR-499-5p in neurons. miR-499-5p overexpression in the hippocampus in vivo induces short-term memory impairments selectively in rats haploinsufficient for the Cav1.2 pore forming subunit Cacna1c. In humans, miR-499-5p expression is negatively associated with gray matter volumes of the left superior temporal gyrus, a region implicated in auditory and emotional processing. We propose that stress-induced miR-499-5p overexpression contributes to dendritic impairments, deregulated calcium homeostasis, and neurocognitive dysfunction in BD.

The quiet crossing of ocean tipping points.

Anthropogenic climate change profoundly alters the ocean's environmental conditions, which, in turn, impact marine ecosystems. Some of these changes are happening fast and may be difficult to reverse. The identification and monitoring of such changes, which also includes tipping points, is an ongoing and emerging research effort. Prevention of negative impacts requires mitigation efforts based on feasible research-based pathways. Climate-induced tipping points are traditionally associated with singular catastrophic events (relative to natural variations) of dramatic negative impact. High-probability high-impact ocean tipping points due to warming, ocean acidification, and deoxygenation may be more fragmented both regionally and in time but add up to global dimensions. These tipping points in combination with gradual changes need to be addressed as seriously as singular catastrophic events in order to prevent the cumulative and often compounding negative societal and Earth system impacts.

TLR2 and 4 signaling pathways are altered in macrophages from V30M TTR mice with down-regulated expression of chemokines.

Hereditary amyloid transthyretin (ATTRv) amyloidosis is a fatal neurodegenerative disorder, first identified in Portugal. The most common transthyretin (TTR) mutation in ATTRv results from an exchange of a methionine for a valine at position 30 (V30M). ATTRv is characterized by the extracellular deposition of aggregates and fibrils of mutant forms of TTR, particularly in the nerves and ganglia of the peripheral nervous system (PNS). This phenotype is often accompanied by the lack of inflammatory infiltrates, despite the importance of macrophages in removal of TTR deposits in ATTRv patients. The mechanisms underlying this impairment of inflammatory responses in ATTRv patients are poorly understood. Here, we show a significant down-regulation in the expression of several chemokines by bone marrow-derived macrophages (BMDM) generated from V30M TTR mice upon stimulation with toll-like receptor 4 (TLR4) and TLR2 agonists. The phosphorylation of the MAP kinase p38, important for TLR4 and TLR2 signaling pathways, was also down-regulated in V30M macrophages, as compared with wild-type (WT) ones. The present study contributes with new insights to unravel the molecular mechanisms underlying the lack of inflammatory immune responses observed in ATTRv patients and may help in the development of new immune therapeutic strategies for the disease.

Depression: a new enzyme AT play.

Neuronal activity is the main contributor to the high-energy demand of the human brain. ATP is needed for the maintenance of ionic gradients, neurotransmitter transport, and release, as well as the signaling pathways that follow activation of post-synaptic receptors. The inability to maintain a high supply of ATP through tight regulatory mechanisms can, therefore, have severe consequences for brain function. In this issue of EMBO Reports, Cui et al [1] show that pharmacological inhibition or genetic inactivation of CD39, an ectonucleotide tri(di)phosphohydrolase responsible for converting ATP into AMP, has antidepressant-like effects by maintaining high extracellular ATP levels in the presence of stress.

Predictors of physical activity promotion in clinical practice: a cross-sectional study among medical doctors.

BACKGROUND: Physical activity is a major determinant of physical and mental health. International recommendations identify health professionals as pivotal agents to tackle physical inactivity. This study sought to characterize medical doctors' clinical practices concerning the promotion of patients' physical activity, while also exploring potential predictors of the frequency and content of these practices, including doctors' physical activity level and sedentary behaviours. METHODS: A cross-sectional study assessed physical activity promotion in clinical practice with a self-report questionnaire delivered through the national medical prescription software (naturalistic survey). Physical activity and sedentary behaviours were estimated using the International Physical Activity Questionnaire (short form). Indicators of medical doctors' attitudes, knowledge, confidence, barriers, and previous training concerning physical activity promotion targeting their patients were also assessed. Multiple regression analysis was performed to identify predictors of physical activity promotion frequency by medical doctors, including sociodemographic, attitudes and knowledge-related variables, and physical activity behaviours as independent variables. RESULTS: A total of 961 medical doctors working in the Portuguese National Health System participated (59% women, mean age 44 ± 13 years) in the study. The majority of the participants (84.6%) reported to frequently promote patients' physical activity. Five predictors of physical activity promotion frequency emerged from the multiple regression analysis, explaining 17.4% of the dependent variable (p < 0.001): working in primary healthcare settings (p = 0.037), having a medical specialty (p = 0.030), attributing a high degree of relevance to patients' physical activity promotion in healthcare settings (p < 0.001), being approached by patients to address physical activity (p < 0.001), and having higher levels of physical activity (p = 0.001). CONCLUSIONS: The sample of medical doctors approached reported a high level of engagement with physical activity promotion. Physical activity promotion frequency seems to be influenced by the clinical practice setting, medical career position and specialty, attitudes towards physical activity, and perception of patients´ interest on the topic, as well as medical doctors' own physical activity levels.

Controlling false discoveries in genome scans for selection.

Population differentiation (PD) and ecological association (EA) tests have recently emerged as prominent statistical methods to investigate signatures of local adaptation using population genomic data. Based on statistical models, these genomewide testing procedures have attracted considerable attention as tools to identify loci potentially targeted by natural selection. An important issue with PD and EA tests is that incorrect model specification can generate large numbers of false-positive associations. Spurious association may indeed arise when shared demographic history, patterns of isolation by distance, cryptic relatedness or genetic background are ignored. Recent works on PD and EA tests have widely focused on improvements of test corrections for those confounding effects. Despite significant algorithmic improvements, there is still a number of open questions on how to check that false discoveries are under control and implement test corrections, or how to combine statistical tests from multiple genome scan methods. This tutorial study provides a detailed answer to these questions. It clarifies the relationships between traditional methods based on allele frequency differentiation and EA methods and provides a unified framework for their underlying statistical tests. We demonstrate how techniques developed in the area of genomewide association studies, such as inflation factors and linear mixed models, benefit genome scan methods and provide guidelines for good practice while conducting statistical tests in landscape and population genomic applications. Finally, we highlight how the combination of several well-calibrated statistical tests can increase the power to reject neutrality, improving our ability to infer patterns of local adaptation in large population genomic data sets.

Identifying outlier loci in admixed and in continuous populations using ancestral population differentiation statistics.

Finding genetic signatures of local adaptation is of great interest for many population genetic studies. Common approaches to sorting selective loci from their genomic background focus on the extreme values of the fixation index, FST , across loci. However, the computation of the fixation index becomes challenging when the population is genetically continuous, when predefining subpopulations is a difficult task, and in the presence of admixed individuals in the sample. In this study, we present a new method to identify loci under selection based on an extension of the FST statistic to samples with admixed individuals. In our approach, FST values are computed from the ancestry coefficients obtained with ancestry estimation programs. More specifically, we used factor models to estimate FST , and we compared our neutrality tests with those derived from a principal component analysis approach. The performances of the tests were illustrated using simulated data and by re-analysing genomic data from European lines of the plant species Arabidopsis thaliana and human genomic data from the population reference sample, POPRES.

Molecular characterization of hepatitis C virus for determination of subtypes and detection of resistance mutations to protease inhibitors in a group of intravenous drug users co-infected with HIV.

Modifications in therapeutic regimens for the treatment of hepatitis C virus (HCV) have been observed since the approval of viral protease inhibitors (PI), and the selection of natural drug-resistant variants has been also reported. Thus, it becomes crucial to be aware of consequences of new therapeutic approaches and make available tools for monitoring the infection. The study aimed to apply an "in-house" method for amplification and sequencing of the NS3 region which is the target of PI, and allowing simultaneously the classification of viral subtypes and identification of resistance mutations. Forty-seven samples collected from HIV injecting drug users and drug naive for HCV protease inhibitors were tested for anti-HCV antibodies, 93.6% of them had a positive result and in 70.5% was determined HCV active infection. High frequency of subtype 1a (46.2%), followed by an equal proportion of subtypes 3a, 4a, and 4d (15.4%) was obtained. Two potential recombinants, RF1_2k/1b (3.8%) and 2q/2k (3.8%) were identified. Substitutions V36L/P, T54A, I72L/N/T/V, Q80K/G, S122R/T, D168Q, and I170L/V were observed in 65.4% of the samples. The T54A and Q80K mutations, and the combination V36L + T54A were also identified. Polymorphisms were observed exclusively associated with specific genotypes, particularly, I72L and D168Q with genotype 3, and S122T with genotype 4. The V36L substitution was identified in 92.8% of sequences of non-genotype 1 denoting that this amino acid substitution is a natural polymorphism associated with non-genotype 1 strains. Although no major PI resistance mutations were detected, a more extensive study is needed to evaluate the impact of mutations identified in efficacy of PI treatment.

Asymmetric c-fos expression in the ventral orbital cortex is associated with impaired reversal learning in a right-sided neuropathy.

BACKGROUND: Recently we showed that unilateral peripheral neuropathic lesions impacted differentially on rat's emotional/cognitive behavior depending on its left/right location; importantly, this observation recapitulates clinical reports. The prefrontal cortex (PFC), a brain region morphofunctionally affected in chronic pain conditions, is involved in the modulation of both emotion and executive function and displays functional lateralization. To test whether the PFC is involved in the lateralization bias associated with left/right pain, c-fos expression in medial and orbital areas was analyzed in rats with an unilateral spared nerve injury neuropathy installed in the left or in the right side after performing an attentional set-shifting, a strongly PFC-dependent task. RESULTS: SNI-R animals required more trials to successfully terminate the reversal steps of the attentional set-shifting task. A generalized increase of c-fos density in medial and orbital PFC (mPFC/OFC), irrespectively of the hemisphere, was observed in both SNI-L and SNI-R. However, individual laterality indexes revealed that contrary to controls and SNI-L, SNI-R animals presented a leftward shift in c-fos density in the ventral OFC (VO). None of these effects were observed in the neighboring primary motor area. CONCLUSIONS: Our results demonstrate that chronic neuropathic pain is associated with a bilateral mPFC and OFC hyperactivation. We hypothesize that the impaired performance of SNI-R animals is associated with a left/right activity inversion in the VO, whose functional integrity is critical for reversal learning.

Orogenital and anal infection by Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, and other sexually transmitted infections in men who have sex with men in Lisbon.

BACKGROUND: Men who have sex with men (MSM) are at risk for sexually transmitted infections (STIs), but more data on extragenital carriage are needed. AIM: We assessed the genital and extragenital prevalence of bacterial and other STIs in MSM in a Lisbon sexual health clinic. METHODS: We screened oral, anal, and urine samples of MSM visiting the GAT-CheckpointLX clinic June 2017-December 2021 for Chlamydia trachomatis (including lymphogranuloma venereum, LGV), Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, Mycoplasma hominis, Ureaplasma urealyticum, and U. parvum. Ano-oro-genital lesions were tested for LGV, Treponema pallidum, and Herpes Simplex Virus. Blood was tested for HIV and T. pallidum antibodies. RESULTS: N. gonorrhoeae was found in 16.6% of the MSM followed by C. trachomatis (13.2%), M. genitalium (10.3%) and T. vaginalis (0.2%). The most frequent occurrence was anorectal (C. trachomatis, M. genitalium) and oral (N. gonorrhoeae). We found high carriage of U. urealyticum (36.1%) and M. hominis (22.1%). LGV was detected in 21.8% of chlamydia-positive anorectal swabs. Syphilis was detected in 22.6% of tested MSM, while 13.8% had HIV. Gonorrhoea and chlamydia were significantly more prevalent in MSM with concomitant HIV or syphilis. CONCLUSION: The substantial extragenital prevalence of bacterial STIs in MSM, and HIV and syphilis coinfections, suggest screening has value in identifying hidden carriage and in contributing for providing better care.

Comparison of automated methods for measurement of 25-hydroxyvitamin D.

BACKGROUND: The objective of the study was to compare the analytical performance of three automated immunoassays for the determination of serum 25-hydroxyvitamin D. METHODS: Quantitative determination of serum 25(OH)D were performed by "Vitamin D total" (n = 131) and "Vitamin D3(25-OH)" (n = 77) assays (Roche Diagnostics) on a Cobas e411 and by "25-OH Vitamin D" (n = 131) assay (Abbott Laboratories) on an Architect. The inter-assay precision was calculated and methods were compared by the Passing Bablok regression and Bland-Altman analysis. RESULTS: The "Vitamin D total" demonstrated stronger correlation (r = 0.863) and better agreement (bias = -7.89 nmol/L) with the "25-OH Vitamin D" than with the "Vitamin D3(25-OH)" (r = 0.716; bias = +18.6 nmol/L). The inter-assay precision (% CV) for the "Vitamin D total" and "25-OH Vitamin D" assays, were respectively 3.47 to 6.14 and 4.27 to 8.56. CONCLUSIONS: The results of this study demonstrate that Abbott "25-OH Vitamin D" and Roche "Vitamin D total" are rapid and precise methods for 25(OH)D serum measurement over a wide reportable range on automated immunoassay platforms. The Abbott assay exhibited better correlation and agreement with the new Roche assay than the "Vitamin D3(25-OH)" Roche assay. Between method differences observed in this study still indicates the need for standardization of 25(OH)D assays.

Cellular environment of TTR deposits in an animal model of ATTR-Cardiomyopathy.

Introduction: Cardiac amyloidoses are the most fatal manifestation of systemic amyloidoses. It is believed the number of cases to be greatly underestimated mostly due to misdiagnosis. Particularly, the involvement of TTR V30M in the heart of ATTRV30M amyloidosis has not been completely understood specifically in terms of implicated cellular pathways, heart function and cardiac physiology. In the present work we proposed to characterize TTR V30M cardiac involvement particularly at the tissue cellular level in a mouse model. Methods: HSF ± hTTR V30M mice, a model that expresses human TTRV30M in a Ttr null background, widely used for the characterization and modulation of neurological features of ATTRV30M amyloidosis was used. SDS-PAGE of cardiac homogenates followed by Western blot was performed. Immunohistochemistry and double immunofluorescence analyses were carried out to determine TTR deposition pattern and sub-localization. Results: Western blots were able to detect TTR in its monomeric state at ∼14 kDa. Immunofluorescent images showed TTR was found mostly in the intercellular spaces. Blood contamination was excluded by CD31 staining. Tissues were Congo Red negative. Upon TTR and macrophages (CD68) staining in the cardiac tissue a clear tendency of macrophage convergence to the tissue regions where TTR was more abundant was observed. Moreover, in some instances it was possible to detect co-localization of both fluorophores. Cardiac fibroblasts were stained with PDGFr-alpha, and here the co-localization was not so evident although there was some degree of co-occurrence. The hearts of transgenic mice revealed higher content of Galectin-3. Conclusion: This animal model and associated features observed as result of cardiac TTR deposition provide a promising and invaluable research tool for a better understanding of the implicated pathways that lead to the lethality associated to TTR cardiac amyloidosis. New therapeutic strategies can be tested and ultimately this will lead to improved treatment alternatives capable of increasing patient's quality of life and life expectancy and, hopefully to eradicate a condition that is silently spreading worldwide.

Group recommender systems for tourism: how does personality predict preferences for attractions, travel motivations, preferences and concerns?

To travel in leisure is an emotional experience, and therefore, the more the information about the tourist is known, the more the personalized recommendations of places and attractions can be made. But if to provide recommendations to a tourist is complex, to provide them to a group is even more. The emergence of personality computing and personality-aware recommender systems (RS) brought a new solution for the cold-start problem inherent to the conventional RS and can be the leverage needed to solve conflicting preferences in heterogenous groups and to make more precise and personalized recommendations to tourists, as it has been evidenced that personality is strongly related to preferences in many domains, including tourism. Although many studies on psychology of tourism can be found, not many predict the tourists' preferences based on the Big Five personality dimensions. This work aims to find how personality relates to the choice of a wide range of tourist attractions, traveling motivations, and travel-related preferences and concerns, hoping to provide a solid base for researchers in the tourism RS area to automatically model tourists in the system without the need for tedious configurations, and solve the cold-start problem and conflicting preferences. By performing Exploratory and Confirmatory Factor Analysis on the data gathered from an online questionnaire, sent to Portuguese individuals from different areas of formation and age groups (n = 1035), we show all five personality dimensions can help predict the choice of tourist attractions and travel-related preferences and concerns, and that only neuroticism and openness predict traveling motivations.

Advantageous use of lenalidomide in multiple myeloma: discussion of three case studies.

PURPOSE OF REVIEW: Although multiple myeloma remains an essentially incurable disease, treatment options and patients' quality of life have improved over the last years with the introduction of more effective and less toxic agents. Therapy should be tailored to the clinical circumstance of each patient under consideration of factors such as patient age, comorbidities (e.g. history of renal failure, thromboembolism or neuropathy) and performance status. RECENT FINDINGS: This article presents three Portuguese clinical cases, illustrating the efficacy and good tolerability profile of lenalidomide in combination with dexamethasone, especially when used as second-line therapy. In particular, these cases illustrate the benefit of using such combinations in patients previously treated with thalidomide as well as patients with peripheral neuropathy or renal impairment. Finally, the last case highlights the importance of timely administration of effective thromboembolism prophylaxis in the presence of prothrombotic risk factors. SUMMARY: These cases are discussed in light of the current knowledge of achieving the best quality of life for the patients, while minimizing myeloma burden and improving existing organ damage due to either the presence of multiple myeloma or to previous therapies.

Necrotizing fasciitis of the vulva due to carbapenem-resistant Enterobacteriaceae as a complication of acute myeloid leukemia treatment: a case report.

BACKGROUND: Carbapenem-resistant Enterobacteriaceae strains have been reported in healthcare facilities with a rising incidence and are a major concern owing to infections that are often severe and can be potentially fatal, with limited therapeutic options. Klebsiella pneumonia represents the most frequently isolated microorganism. CASE PRESENTATION: We report the case of a Caucasian 52-year old Caucasian woman with acute myeloid leukemia was admitted to the inpatient hematology unit at a university referral hospital in Portugal. This hospital has endemic colonization of Carbapenem-resistant Enterobacteriaceae and contention measures are being implemented to reduce spreading of these multidrug resistant bacteria. After receiving first line chemotherapy according to the intermediate-dose cytarabine regimen, in context of deep medullary aplasia, the patient developed a localized infection of the vulva, which progressed to a necrotizing fasciitis. This is a rare, life-threatening, and fulminant infection. Carbapenem-resistant Klebsiella was isolated in both vulvar exudate and blood cultures. The patient underwent multiple schemes of antimicrobials, but progressed with multiorgan compromise and was admitted to the intensive care unit for a short period for stabilization. Surgical debridement was performed twice with clinical improvement and, after 6 weeks, a skin graft was executed with good response. Reevaluation of the hematologic disease showed a complete response to first cycle of induction therapy. Despite success in resolving this complex infection, decisions regarding antibiotic treatment represented a tremendous challenge for the whole team. The importance of multidisciplinary collaboration was key for the patient's recovery and survival, and therefore, needs to be acknowledged. CONCLUSIONS: This clinical case raises awareness on a clinical entity that can be life threatening and, therefore, requires a high level of suspicion to assure an early integrated approach to avoid complications. Endemic spreading of carbapenem-resistant Enterobacteriaceae is becoming a reality, and health policies need to be urgently undertaken at the national level to decrease morbidity and mortality because of health facilities-related infections.

The role of common genetic variation in presumed monogenic epilepsies.

BACKGROUND: The developmental and epileptic encephalopathies (DEEs) are the most severe group of epilepsies which co-present with developmental delay and intellectual disability (ID). DEEs usually occur in people without a family history of epilepsy and have emerged as primarily monogenic, with damaging rare mutations found in 50% of patients. Little is known about the genetic architecture of patients with DEEs in whom no pathogenic variant is identified. Polygenic risk scoring (PRS) is a method that measures a person's common genetic burden for a trait or condition. Here, we used PRS to test whether genetic burden for epilepsy is relevant in individuals with DEEs, and other forms of epilepsy with ID. METHODS: Genetic data on 2,759 cases with DEEs, or epilepsy with ID presumed to have a monogenic basis, and 447,760 population-matched controls were analysed. We compared PRS for 'all epilepsy', 'focal epilepsy', and 'genetic generalised epilepsy' (GGE) between cases and controls. We performed pairwise comparisons between cases stratified for identifiable rare deleterious genetic variants and controls. FINDINGS: Cases of presumed monogenic severe epilepsy had an increased PRS for 'all epilepsy' (p<0.0001), 'focal epilepsy' (p<0.0001), and 'GGE' (p=0.0002) relative to controls, which explain between 0.08% and 3.3% of phenotypic variance. PRS was increased in cases both with and without an identified deleterious variant of major effect, and there was no significant difference in PRS between the two groups. INTERPRETATION: We provide evidence that common genetic variation contributes to the aetiology of DEEs and other forms of epilepsy with ID, even when there is a known pathogenic variant of major effect. These results provide insight into the genetic underpinnings of the severe epilepsies and warrant a shift in our understanding of the aetiology of the DEEs as complex, rather than monogenic, disorders. FUNDING: Science foundation Ireland, Human Genome Research Institute; National Heart, Lung, and Blood Institute; German Research Foundation.

SARS-CoV-2 introductions and early dynamics of the epidemic in Portugal.

Background: Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration with more than 50 laboratories distributed nationwide. Methods: By applying recent phylodynamic models that allow integration of individual-based travel history, we reconstructed and characterized the spatio-temporal dynamics of SARS-CoV-2 introductions and early dissemination in Portugal. Results: We detected at least 277 independent SARS-CoV-2 introductions, mostly from European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland), which were consistent with the countries with the highest connectivity with Portugal. Although most introductions were estimated to have occurred during early March 2020, it is likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the first cases were confirmed. Conclusions: Here we conclude that the earlier implementation of measures could have minimized the number of introductions and subsequent virus expansion in Portugal. This study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.

Genetic and functional analyses implicate microRNA 499A in bipolar disorder development.

Bipolar disorder (BD) is a complex mood disorder with a strong genetic component. Recent studies suggest that microRNAs contribute to psychiatric disorder development. In BD, specific candidate microRNAs have been implicated, in particular miR-137, miR-499a, miR-708, miR-1908 and miR-2113. The aim of the present study was to determine the contribution of these five microRNAs to BD development. For this purpose, we performed: (i) gene-based tests of the five microRNA coding genes, using data from a large genome-wide association study of BD; (ii) gene-set analyses of predicted, brain-expressed target genes of the five microRNAs; (iii) resequencing of the five microRNA coding genes in 960 BD patients and 960 controls and (iv) in silico and functional studies for selected variants. Gene-based tests revealed a significant association with BD for MIR499A, MIR708, MIR1908 and MIR2113. Gene-set analyses revealed a significant enrichment of BD associations in the brain-expressed target genes of miR-137 and miR-499a-5p. Resequencing identified 32 distinct rare variants (minor allele frequency < 1%), all of which showed a non-significant numerical overrepresentation in BD patients compared to controls (p = 0.214). Seven rare variants were identified in the predicted stem-loop sequences of MIR499A and MIR2113. These included rs142927919 in MIR2113 (pnom = 0.331) and rs140486571 in MIR499A (pnom = 0.297). In silico analyses predicted that rs140486571 might alter the miR-499a secondary structure. Functional analyses showed that rs140486571 significantly affects miR-499a processing and expression. Our results suggest that MIR499A dysregulation might contribute to BD development. Further research is warranted to elucidate the contribution of the MIR499A regulated network to BD susceptibility.

MicroRNA-dependent control of neuroplasticity in affective disorders.

Affective disorders are a group of neuropsychiatric disorders characterized by severe mood dysregulations accompanied by sleep, eating, cognitive, and attention disturbances, as well as recurring thoughts of suicide. Clinical studies consistently show that affective disorders are associated with reduced size of brain regions critical for mood and cognition, neuronal atrophy, and synaptic loss in these regions. However, the molecular mechanisms that mediate these changes and thereby increase the susceptibility to develop affective disorders remain poorly understood. MicroRNAs (miRNAs or miRs) are small regulatory RNAs that repress gene expression by binding to the 3'UTR of mRNAs. They have the ability to bind to hundreds of target mRNAs and to regulate entire gene networks and cellular pathways implicated in brain function and plasticity, many of them conserved in humans and other animals. In rodents, miRNAs regulate synaptic plasticity by controlling the morphology of dendrites and spines and the expression of neurotransmitter receptors. Furthermore, dysregulated miRNA expression is frequently observed in patients suffering from affective disorders. Together, multiple lines of evidence suggest a link between miRNA dysfunction and affective disorder pathology, providing a rationale to consider miRNAs as therapeutic tools or molecular biomarkers. This review aims to highlight the most recent and functionally relevant studies that contributed to a better understanding of miRNA function in the development and pathogenesis of affective disorders. We focused on in vivo functional studies, which demonstrate that miRNAs control higher brain functions, including mood and cognition, in rodents, and that their dysregulation causes disease-related behaviors.