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The role of experience in the organization of cortical feedback (FB) remains unknown. We measured the effects of manipulating visual experience on the retinotopic specificity of supragranular and infragranular projections from the lateromedial (LM) visual area to layer (L)1 of the mouse primary visual cortex (V1). LM inputs were, on average, retinotopically matched with V1 neurons in normally and dark-reared mice, but visual exposure reduced the fraction of spatially overlapping inputs to V1. FB inputs from L5 conveyed more surround information to V1 than those from L2/3. The organization of LM inputs from L5 depended on their orientation preference and was disrupted by dark rearing. These observations were recapitulated by a model where visual experience minimizes receptive field overlap between LM inputs and V1 neurons. Our results provide a mechanism for the dependency of surround modulations on visual experience and suggest how expected interarea coactivation patterns are learned in cortical circuits.
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Glioblastoma (GBM) is a malignant brain tumor with uncontrolled invasive growth. Here, we demonstrate how GBM cells usurp guidance receptor Plexin-B2 to gain biomechanical plasticity for polarized migration through confined space. Using live-cell imaging to track GBM cells negotiating microchannels, we reveal active endocytosis at cell front and filamentous actin assembly at rear to propel GBM cells through constrictions. These two processes are interconnected and governed by Plexin-B2 that orchestrates cortical actin and membrane tension, shown by biomechanical assays. Molecular dynamics simulations predict that balanced membrane and actin tension are required for optimal migratory velocity and consistency. Furthermore, Plexin-B2 mechanosensitive function requires a bendable extracellular ring structure and affects membrane internalization, permeability, phospholipid composition, as well as inner membrane surface charge. Together, our studies unveil a key element of membrane tension and mechanoelectrical coupling via Plexin-B2 that enables GBM cells to adapt to physical constraints and achieve polarized confined migration.
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Stingless bees are major flower visitors in the tropics, but their foraging preferences and behavior are still poorly understood. Studying stingless bee interactions with angiosperms is methodologically challenging due to the high tropical plant diversity and inaccessibility of upper canopy flowers in forested habitats. Pollen DNA metabarcoding offers an opportunity of assessing floral visitation efficiently and was applied here to understand stingless bee floral resources spectra and foraging behavior. We analyzed pollen and honey from nests of three distantly related stingless bee species, with different body size and social behavior: Melipona rufiventris, Scaptotrigona postica and Tetragonisca angustula. Simultaneously, we evaluate the local floristic components through seventeen rapid botanical surveys conducted at different distances from the nests. We discovered a broad set of explored floral sources, with 46.3 plant species per bee species in honey samples and 53.67 in pollen samples. Plant families Myrtaceae, Asteraceae, Euphorbiaceae, Melastomataceae and Malpighiaceae dominated the records, indicating stingless bee preferences for abundant resources that flowers of these families provide in the region. Results also reinforce the preference of stingless bees for forest trees, even if only available at long distances. Our high-resolution results encourage future bee-plant studies using pollen and honey metabarcoding in hyper-diverse tropical environments.
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Asteraceae , Miel , Abejas , Animales , Polen , Conducta Social , Tamaño CorporalRESUMEN
The present study aimed to evaluate the potential and specificity of the inflammatory and antioxidant response of Microbe-Associated Molecular Patterns (MAMPs) in NIH-3T3 fibroblast cells, as well as in the healing process of skin wounds. Cells (NIH-3T3) were cultivated in supplemented specific medium. NIH-3T3 cells were treated with MAMPs (Bifidobacterium lactis or Lactobacillus casei or Lactobacillus gasseri or Lactobacillus paracasei or Streptococcus thermophilus), at two concentrations and insulted with LPS or H2O2. Cell viability, myeloperoxidase activity, nitrite/nitrate, oxidative damage and inflammatory parameters were measured. In addition, scratch assay was performed. Significant scratch closure was observed after 24 h and 48 h, and the effect of 0.1 g/mL MAMPs on wound healing was found to be highly statistically significant. In the viability cellular assay, Lactobacillus showed better response in 0.1 g/mL dose, whereas B. lactis and S. thermophilus showed better response in 0.01 g/mL dose. There was reduction in IL-6 and IL-1ß levels in all treatments insulted with LPS. MAMP's showed preventive efficacy in reducing the effects caused by LPS. The MAMP's action in decreasing the production of ROS, inflammatory activity and increasing cell viability, besides significant cell proliferation during wound healing processes suggests remodeling mechanisms and new possibilities for wound healing.
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Peróxido de Hidrógeno , Repitelización , Ratones , Animales , Células 3T3 NIH , Peróxido de Hidrógeno/farmacología , Lipopolisacáridos , Cicatrización de Heridas/fisiología , Estrés Oxidativo , Antioxidantes/farmacologíaRESUMEN
Some of the icy moons of the solar system with a subsurface ocean, such as Europa and Enceladus, are the targets of future space missions that search for potential extraterrestrial life forms. While the ice shells that envelop these moons have been studied by several spacecrafts, the oceans beneath them remain unreachable. To better constrain the habitability conditions of these moons, we must understand the interactions between their frozen crusts, liquid layers, and silicate mantles. To that end, astrobiologists rely on planetary field analogues, for which the polar regions of Earth have proven to be great candidates. This review shows how spectroscopy is a powerful tool in space missions to detect potential biosignatures, in particular on the aforementioned moons, and how the polar regions of the Earth are being used as planetary field analogues for these extra-terrestrial environments.
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Background: The SARS-CoV virus is a precursor to the SARS-CoV-2 virus (COVID-19) and has caused millions of deaths worldwide. Although exercise can be a non-pharmacological means for the prevention and treatment of various diseases, the effects on COVID-19 patients are not yet completely clear. Aims: The aim of this study was to investigate the relationship between physical exercise and symptoms caused by COVID-19. Methods: The present systematic review was sent for evaluation and received the PROSPERO registration protocol-CRD42021257475. The search for studies related to health and physical exercise was carried out in the following databases; the "National Library in Medicine MEDLINE-Ovid", "Embase", "Web of Science", "SportDiscus-Ebsco", and "Scopus". Results: Ten articles were included in the systematic review and the findings demonstrated the protective effects of physical exercise in patients with COVID-19. These effects were observed both in symptoms and in the period of hospitalization. In addition, the results show that the benefits of physical exercise seem to collaborate both in an individual manner and as an alternative to drug therapy. Finally, it was possible to verify the effect of physical exercise on variables, such as quality of life, cardiorespiratory capacity, and immunological biomarkers, and on the symptoms of the new Coronavirus. Conclusions: It is possible to conclude that physical exercise can be a component for the treatment of COVID-19. In addition, it could help to reduce the symptoms and severity of COVID-19, and may be considered as an adjunct to drug therapy in patients contaminated with SARS-CoV-2.
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The study evaluated the effects of supplementation with three different probiotic strains Bifidobacterium lactis (LACT GB™), Lactobacillus rhamnosus (RHAM GB™) and Lactobacillus reuteri (REUT GB™) on brain-intestinal immunomodulation in an animal model of LPS-induced inflammation. Fifty mice Balb/C were distributed into five groups: control; lipopolysaccharide (LPS); LPS + B. lactis (LACT GB™); LPS + L. rhamnosus (RHAM GB™); and LPS + L. reuteri (REUT GB™). The animals were supplemented with their respective probiotic microorganisms daily, for 30 days, at a concentration of 1 × 109 CFU/animal/day. After 30 days of supplementation, animals received the inflammatory insult by LPS (15 mg/kg). Behavioral tests, oxidative stress and inflammation were performed, as well as gut and brain histology. In the behavioral test, LPS + B. lactis group was less anxious than the other groups. Serum interleukin IL-1ß and IL-6 levels increased in all groups that received the LPS insult, and there was a reduction in inflammation in the supplemented groups when compared to the LPS group in brain and gut. There is a reduction in myeloperoxidase activity and oxidative stress in groups supplemented with probiotics. In intestine histological analysis occurs damage to the tissue integrity in the LPS group, in the other hand, occurs preservation of integrity in the probiotic supplemented animals. In the brain, infiltrates of perivascular inflammatory cells can be seen in the LPS group. The three probiotic studies showed efficient immunomodulating activity and ensured integrity of the intestinal barrier function, even after the severe insult by LPS. These results show the important role of probiotics in the gut-brain axis. Graphical abstract illustratively represents the gut-brain axis and how different probiotic strains influence the immunomodulatory response releasing different pro- and anti-inflammatory cytokines, and their role in the balance of dysbiosis.
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Limosilactobacillus reuteri , Probióticos , Animales , Encéfalo , Endotoxinas , Inmunomodulación , Inflamación , Lipopolisacáridos/farmacología , Ratones , Probióticos/farmacología , Probióticos/uso terapéuticoRESUMEN
Antimicrobial peptides (AMPs) can efficiently control different microbial pathogens and show the potential to be applied in clinical practice and livestock production. In this work, the aim was to isolate AMP-producing ruminal streptococci and to characterize their genetic features through whole-genome sequencing. We cultured 463 bacterial isolates from the rumen of Nelore bulls, 81 of which were phenotypically classified as being Streptococcaceae. Five isolates with broad-range activity were genome sequenced and confirmed as being Streptococcus lutetiensis. The genetic features linked to their antimicrobial activity or adaptation to the rumen environment were characterized through comparative genomics. The genome of S. lutetiensis UFV80 harbored a putative CRISPR-Cas9 system (Type IIA). Computational tools were used to discover novel biosynthetic clusters linked to the production of bacteriocins. All bacterial genomes harbored genetic clusters related to the biosynthesis of class I and class II bacteriocins. SDS-PAGE confirmed the results obtained in silico and demonstrated that the class II bacteriocins predicted in the genomes of three S. lutetiensis strains had identical molecular mass (5197 Da). These results demonstrate that ruminal bacteria of the Streptococcus bovis/equinus complex represent a promising source of novel antimicrobial peptides.
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INTRODUCTION: Necrotizing Enterocolitis (NEC) is a serious intestinal disease that affects premature neonates, causing high mortality, despite the technological development in neonatal intensive care, with antibiotics, parenteral nutrition, surgery, and advanced life support. The correction of dysbiosis with fecal microbiome transplantation (FMT) has shown beneficial effects in experimental models of the disease. The different forms of administration and conservation of FMT and mixed results depending on several factors lead to questions about the mechanism of action of FMT. This study aimed to compare the effectiveness of fresh, sterile FMT and probiotic treatment under parameters of inflammation, oxidative stress, and tissue damage in a neonatal model of NEC. METHODS: One-day-old Wistar rats were used to induce NEC model. Animals were divided in five groups: Control + saline; NEC + saline; NEC + fresh FMT; NEC + sterile FMT and NEC+ probiotics. Parameters of inflammatory response and oxidative damage were measured in the gut, brain, and serum. It was also determined gut histopathological alterations. RESULTS: Proinflammatory cytokines were increased in the NEC group, and IL-10 levels decreased in the gut, brain, and serum. Fresh and sterile FMT decreased inflammation when compared to the use of probiotics. Oxidative and histological damage to the intestine was apparent in the NEC group, and both FMT treatments had a protective effect. CONCLUSION: Fresh and sterile FMT effectively reduced the inflammatory response, oxidative damage, and histological alterations in the gut and brain compared to an experimental NEC model.
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Enterocolitis Necrotizante , Enfermedades Fetales , Microbioma Gastrointestinal , Enfermedades del Recién Nacido , Animales , Enterocolitis Necrotizante/terapia , Trasplante de Microbiota Fecal , Femenino , Humanos , Recién Nacido , Inflamación/patología , Modelos Animales , Ratas , Ratas WistarRESUMEN
Major congenital anomalies are known to play a role in the management and prognosis of airway obstruction. Most studies assess acquired forms of airway obstruction. Data on congenital or otherwise non-acquired forms of airway obstruction is sparse. In this retrospective, single-institution cohort study, we sought to evaluate and compare the patterns of airway obstruction in children with and without major congenital anomalies, and to assess the impact of management and outcome, irrespective of aetiology. Fifty-five patients were included, 23 with and 32 without underlying major congenital anomalies. Multilevel airway obstruction (usually affecting the nasopharynx, oropharynx, and the trachea) was more common in children with congenital anomalies (91% vs. 41%, p < .001). Consequently, these children required more frequent and earlier surgical management, especially tracheostomy and adenotonsillar surgery.Conclusions: Major congenital anomalies are associated with multilevel airway obstruction and poor functional prognosis. A simple clinical definition considering impact of major congenital anomalies on development and growth may help guide management plans following endoscopic evaluation of the entire airway and flanked by multidisciplinary discussions. What is Known: ⢠Children with major comorbidities display increased disease severity and more prevalent multilevel airway obstruction ⢠Previous studies include both children with acquired and non-acquired forms of airway obstruction; therefore, the actual impact major comorbidities in children with non-acquired causes of airway obstruction remain unclear. What is New: ⢠A total of 42% children in this study population had major comorbidities with and impact on growth and/or psychomotor development, with a higher prevalence of multilevel airway obstruction and worse rates of functional improvement/recovery. ⢠Children with major comorbidities require tracheostomy more often and earlier than those without major comorbidities, and remain tracheostomy-dependent for a longer time.
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Obstrucción de las Vías Aéreas , Obstrucción de las Vías Aéreas/epidemiología , Obstrucción de las Vías Aéreas/etiología , Niño , Estudios de Cohortes , Humanos , Lactante , Estudios Retrospectivos , Tráquea , TraqueostomíaRESUMEN
BACKGROUND: Sedentary lifestyles are increasingly common amongst children, and insufficient physical activity is a global epidemic estimated to contribute to future incapacities and potential deaths. OBJECTIVE: We aimed to increase the amount of evidence concerning the effect of chronic exposure to exercise on heart rate variability in children and adolescents affected by obesity. METHODS: A systematic review commenced following the PRISMA guidelines developed by Web of Science, Virtual Health Library, PubMed, Cochrane Library, Embase, Ovid, Medline Complete, and Scopus using keywords obtained from the Descriptors in Health Sciences and Medical Subject Headlines (MeSH) terms. We considered (1) Population: Pediatric individuals affected by obesity; (2) Intervention: Exercise; (3) Control: Pre-intervention and sedentary; (4) Outcomes: Clearly presented primary parameters; and (5) Studies: Clinical trials, case controls, case reports, and case series. RESULTS: 11 articles were involved and predominantly included procedures observed during approximately 12 weeks with a distribution of three sessions per week, each session being 30-60 min of aerobic exercise; additionally, the exercise grades were typically completed at a percentage of subjects' maximum heart rates. The meta-analyses displayed a significant effect on the domains of time (R-R interval, SDNN, rMSSD), frequency (HF ms2, HF (n.u.), LF/HF), and the non-linear index (SD1). CONCLUSIONS: Chronic exposure to exercise influences heart rate variability in children and adolescents affected by obesity by elevating the variability and parasympathetic activity and improving the sympathetic-vagal balance. Exercises should be recommended for the improvement of cardiac autonomic modulation to prevent the likelihood of further chronic diseases.
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Sistema Nervioso Autónomo , Ejercicio Físico , Adolescente , Niño , Corazón , Frecuencia Cardíaca , Humanos , ObesidadRESUMEN
During morphogenesis, molecular mechanisms that orchestrate biomechanical dynamics across cells remain unclear. Here, we show a role of guidance receptor Plexin-B2 in organizing actomyosin network and adhesion complexes during multicellular development of human embryonic stem cells and neuroprogenitor cells. Plexin-B2 manipulations affect actomyosin contractility, leading to changes in cell stiffness and cytoskeletal tension, as well as cell-cell and cell-matrix adhesion. We have delineated the functional domains of Plexin-B2, RAP1/2 effectors, and the signaling association with ERK1/2, calcium activation, and YAP mechanosensor, thus providing a mechanistic link between Plexin-B2-mediated cytoskeletal tension and stem cell physiology. Plexin-B2-deficient stem cells exhibit premature lineage commitment, and a balanced level of Plexin-B2 activity is critical for maintaining cytoarchitectural integrity of the developing neuroepithelium, as modeled in cerebral organoids. Our studies thus establish a significant function of Plexin-B2 in orchestrating cytoskeletal tension and cell-cell/cell-matrix adhesion, therefore solidifying the importance of collective cell mechanics in governing stem cell physiology and tissue morphogenesis.
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Actomiosina/metabolismo , Adhesión Celular/fisiología , Citoesqueleto/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Células Madre/metabolismo , Actinas , Sistemas CRISPR-Cas , Diferenciación Celular , Uniones Célula-Matriz/metabolismo , Células Madre Embrionarias , Edición Génica , Expresión Génica , Humanos , Mecanotransducción Celular , Morfogénesis , Células-Madre Neurales , Semaforinas , Transducción de SeñalRESUMEN
BACKGROUND: Bipolar disorder (BD) is a chronic mood disorder characterized by recurrent episodes of mania or hypomania and depression, expressed by changes in energy levels and behavior. However, most of relapse studies use evidence-based approaches with statistical methods. With the advance of the precision medicine this study aims to use machine learning (ML) approaches as a possible predictor in depressive relapses in BD. METHOD: Four accepted and well used ML algorithms (Support Vector Machines, Random Forests, Naïve Bayes, and Multilayer Perceptron) were applied to the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD) dataset in a cohort of 800 patients (507 patients presented depressive relapse and 293 did not), who became euthymic during the study and were followed for one year. RESULTS: The ML algorithms presented reasonable performance in the prediction task, ranging from 61 to 80% in the F-measure. The Random Forest algorithm obtained a higher average of performance (Relapse Group 68%; No Relapse Group 74%). The three most important mood symptoms observed in the relapse visit (Random Forest) were: interest; depression mood and energy. LIMITATIONS: Social and psychological parameters such as marital status, social support system, personality traits, might be an important predictor in depressive relapses, although we did not compute this data in our study. CONCLUSIONS: Our findings indicate that applying precision medicine models by means of machine learning in BD studies could be feasible as a sensible approach to better support medical decision-making in the BD treatment and prevention of future relapses.
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Trastorno Bipolar , Teorema de Bayes , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/terapia , Trastorno Ciclotímico , Humanos , Aprendizaje Automático , RecurrenciaRESUMEN
Individuals with Duchenne Muscular Dystrophy (DMD) have an impairment of cardiac autonomic function categorized by parasympathetic reduction and sympathetic predominance. The objective of this study was to assess the cardiac autonomic modulation of individuals with DMD undergoing therapy with Prednisone/Prednisolone and Deflazacort and compare with individuals with DMD without the use of these medications and a typically developed control group. Methods: A cross-sectional study was completed, wherein 40 boys were evaluated. The four treatment groups were: Deflazacort; Prednisone/Prednisolone; no corticoid use; and typical development. Heart Rate Variability (HRV) was investigated via linear indices (Time Domain and Frequency Domain) and non-linear indices Results: The results of this study revealed that individuals with DMD undertaking pharmacotherapies with Prednisolone demonstrated HRV comparable to the Control Typically Developed (CTD) group. In contrast, individuals with DMD undergoing pharmacotherapies with Deflazacort achieved lower HRV, akin to individuals with DMD without any medications, as demonstrated in the metrics: RMSSD; LF (n.u.), HF (n.u.), LF/HF; SD1, α1, and α1/α2, and a significant effect for SD1/SD2; %DET and Ratio; Shannon Entropy, 0 V%, 2 LV% and 2 ULV%. Conclusions: Corticosteroids have the potential to affect the cardiac autonomic modulation in adolescents with DMD. The use of Prednisone/Prednisolone appears to promote improved responses in terms of sympathovagal activity as opposed to Deflazacort.
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Este estudo consiste em um ensaio teórico que apresenta reflexões acerca das possibilidades e dos desafios impostos pela Base Nacional Comum Curricular. Para tanto, propõe uma discussão sobre república e democracia, localizando a escola como uma instituição formativa necessária para o funcionamento da sociedade. Procura, por fim, analisar o processo de elaboração da base destacando que, embora a efetivação de um currículo comum seja importante para a legitimação da Educação Física como um componente curricular necessário para a escola republicana, o processo final da construção do documento ocorreu de modo pouco democrático, pondo em xeque sua legitimidade.
The present study consists of a theoretical essay that presents reflections on the possibilities and challenges imposed by the National Common Curricular Base. For this, it proposes a discussion on republic and democracy, locating the school as a training institution necessary for the functioning of society. Finally, we seek to analyze the process of preparing the base, highlighting that although the implementation of a common curriculum is important for the legitimation of Physical Education as a necessary curricular component for the republican school, the final process of the construction of the document occurred in an undemocratic way, challenging its legitimacy.
El presente estudio consiste en un ensayo teórico que presenta reflexiones sobre las posibilidades y desafíos que impone la Base Curricular Común Nacional. Para ello propone una discusión sobre república y democracia, ubicando a la escuela como una institución de formación necesaria para el funcionamiento de la sociedad. Finalmente, buscamos analizar el proceso de elaboración de la base, resaltando que, si bien la implementación de un currículo común es importante para la legitimación de la Educación Física como componente curricular necesario para la escuela republicana, se dio el proceso final de construcción del documento. de forma antidemocrática, desafiando su legitimidad.
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Trastorno Bipolar , Infecciones por Coronavirus , Vías Clínicas , Pandemias , Neumonía Viral , Psicoterapia , Aislamiento Social/psicología , Telemedicina/métodos , Betacoronavirus , Trastorno Bipolar/psicología , Trastorno Bipolar/terapia , COVID-19 , Control de Enfermedades Transmisibles/métodos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/psicología , Humanos , Pandemias/prevención & control , Manejo de Atención al Paciente/métodos , Manejo de Atención al Paciente/tendencias , Neumonía Viral/epidemiología , Neumonía Viral/prevención & control , Neumonía Viral/psicología , Guías de Práctica Clínica como Asunto , Distrés Psicológico , Psicoterapia/educación , Psicoterapia/métodos , SARS-CoV-2Asunto(s)
Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Genitales Femeninos/cirugía , Tratamientos Conservadores del Órgano/métodos , Neoplasias del Cuello Uterino/terapia , Adulto , Conización , Femenino , Preservación de la Fertilidad , Procedimientos Quirúrgicos Ginecológicos/métodos , Humanos , Escisión del Ganglio Linfático , Procedimientos Quirúrgicos Robotizados/métodosRESUMEN
Exercise training not only improves the plasma lipid profile but also reduces risk of developing coronary heart disease. We investigate whether plasma lipids and high density lipoprotein (HDL) metabolism are affected by aerobic training and whether the high-density lipoprotein cholesterol (HDL-C) levels at baseline influence exercise-induced changes in HDL. Seventy-one male sedentary volunteers were evaluated and allocated in two subgroups, according to the HLD-C levels (< or >40 mg/dL). Participants underwent an 18-week aerobic training period. Blood was sampled before and after training for biochemical analysis. Plasma lipids, apolipoproteins, HDL diameter, and VO2 peak were determined. Lipid transfers to HDL were determined in vitro by incubating plasma samples with a donor lipid artificial nanoemulsion. After the 18-week period of aerobic training, the VO2 peak increased, while the mean body mass index (BMI) decreased. HDL-C concentration was higher after the training period, but low-density lipoprotein cholesterol (LDL-C) and non-HDL-C did not change. The transfer of esterified cholesterol and phospholipids was greater after exercise training, but the triacylglycerol and unesterified cholesterol transfers were unchanged. The HDL particle diameter increased after aerobic training in all participants. When the participants were separated in low-HDL and normal-HDL groups, the postaerobic exercise increment in HDL-C was higher in the low-HDL group, while the transfer of esterified cholesterol was lower. In conclusion, aerobic exercise training increases the lipid transfers to HDL, as measured by an in vitro method, which possibly contributes to the classical elevation of the HDL-C associated with training.
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Colesterol/metabolismo , Ejercicio Físico , Lipoproteínas HDL/química , Lipoproteínas HDL/metabolismo , Adulto , Colesterol/sangre , Humanos , Lipoproteínas HDL/sangre , Masculino , Tamaño de la Partícula , Adulto JovenRESUMEN
BACKGROUND: Bipolar disorder (BD) is a severe psychiatric disorder characterized by periodic episodes of manic and depressive symptomatology. Predominant polarity (PP) appears to be an important specifier of BD. The present study employed machine learning (ML) algorithms to accurately determine a patient´s PP without the inclusion of number and polarity of past episodes, while exploring associations between PP and demographic and clinical variables. METHODS: From a cohort of 148 BD patients, demographic and clinical variables were collected using a customized questionnaire and the SCID-CV. The algorithm employed was the Random-Forest method. The algorithm was programed to classify patients into either depressive or manic predominant polarities and to reveal which variables were associated to the specifier. RESULTS: The algorithm attained an AUC ROC of 74.72% (95% CIâ¯=â¯72.29-77.15%) in classifying patients into either manic or depressive PP. The variables selected by the algorithm were: (1) age at first depressive episode; (2) number of hospitalizations; (3) BD Type II; (4) manic onset; (5) delusions; (6) psychotic features at onset; (7) tobacco addiction; (8) family history of BD; (9) hallucinations; and (10) comorbid anxiety disorders, (11) alcohol dependence, (12) eating disorders and (13) substance dependence. LIMITATIONS: The study is limited due to the small sample size, the inclusion of only self-reported and clinician-observed clinical variables and its cross-sectional design. DISCUSSION: The results suggest that the ML approach could be effective in determining a patient´s PP. Furthermore, although not previously reported, some variables, such as tobacco use and comorbid eating disorders, appear to be closely associated with PP.