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Purpose: Lesson studies, a methodology originally developed in Japan, has been used in an increasing number of contexts, both in relation to initial teacher training and in the context of ongoing professional development. However, the research reported on the use of lesson studies in the training of physical education teachers is very limited. The aim of this review is to identify and analyze published studies on physical education lesson studies and to describe the advantages of using the methodology in the context of this discipline. Design/methodology/approach: Exploratory searches were carried out in four multiple-search databases, and 14 publications were found. Information was collected about authors, year of publication, origin and type of study, purposes, concept of the lesson study, methodology and results. Findings: The results of the different studies point in the same direction -- potential of lesson studies in physical education in initial training and professional development; valuing collaborative work, contextualization and continuous nature; lesson studies as a significant experience; need to create conditions for teachers' participation in lesson studies; need for further investigation. Originality/value: The research reported on the use of lesson studies in the training of physical education teachers is very limited. This review is intended to cover all studies related to the theme of physical education lesson studies published in indexed journals.

As metodologias ativas constituem um campo promissor de discussão dentro das escolas de Educação Básica. O uso delas propõem a participação ativa dos(as) estudantes no processo de ensino-aprendizagem, por meio de um arcabouço de estratégias didático-pedagógicas, tais como: sala de aula invertida, aprendizagem baseada em projetos e em problemas, gamificação, rotação por estação de aprendizagem e a cultura maker. Nesse sentido, este texto objetiva apresentar uma análise dos textos publicados nos 45 volumes da revista Química Nova na Escola, de 1995 a maio de 2023, identificando as produções que abordam dimensões teórico-práticas do uso de metodologias ativas no ensino de Ciências/Química, especialmente na perspectiva da cultura maker. Verificamos que de todos os textos publicados até maio de 2023, aproximadamente 6,4% tratam sobre o uso de metodologias ativas, no contexto de jogos e estudos de casos, mas não foi identificado nenhum artigo sobre a cultura maker. Percebemos que o uso de novas metodologias de ensino está presente nas salas de aulas, mas ainda é pouco explorado nas pesquisas que se enveredam sobre a Educação em Química.

This study investigated variations in ground temperatures in four cities in Mato Grosso, considering the emission scenario SSP5-8.5 from the Sixth IPCC Assessment Report. Using computational simulations and historical and future climatic data, the research revealed significant changes in average ground temperatures. In Alta Floresta, simulations indicated a notable increase, especially in the months of April, May, and June, contrasting with estimates based on the EPW climatic file. Alto Taquari showed a distinct response, while Campo Verde and Sinop exhibited significant temperature increases until 2080. The research highlights the importance of considering specific soil characteristics for accurate projections, providing crucial insights for climate change adaptation strategies. There is an emphasis on the need to implement passive cooling strategies in buildings, especially in hot regions, to adapt to future conditions.

Resumo Objetivo Comparar o grau de concordância, a correlação e a acurácia entre os instrumentos Edmonton Frail Scale (EFS) e Índice de Vulnerabilidade Clínico-Funcional-20 (IVCF-20) em pessoas idosas com hipertensão arterial sistêmica (HAS). Método Estudo transversal e domiciliar com pessoas idosas de Montes Claros, MG. Este estudo incluiu somente indivíduos com HAS cujos dados foram coletados no período de novembro de 2016 a fevereiro de 2017. Foram determinados a sensibilidade, especificidade e valores preditivos. A estatística Kappa analisou a concordância e confiabilidade, o coeficiente de Pearson avaliou a correlação entre os instrumentos. Resultados 281 eram hipertensas e foram incluídas neste estudo. Constatou-se que a prevalência de fragilidade foi 31,3% pela EFS e 22,1% pelo IVCF-20. A estatística Kappa foi 0,604 e coeficiente de correlação de Pearson foi de 0,621 (p

ABSTRACT Purpose: Acute-on-chronic liver failure (ACLF) is a leading cause of death in cirrhotic patients. This study aims to describe the outcomes of in-patients with ACLF at a liver transplantation (LT) center in Brazil. Methods: Retrospective study analyzing patient data from 2017 to 2022. Re-transplant cases and patients without previous chronic liver disease were excluded. The ACLF diagnosis was based on the European Association for the Study of the Liver-Chronic Liver Failure criteria and assessments repeated on days 3 and 7 after the initial diagnosis. Results: Among 381 patients, 10.49% (n = 40) were diagnosed with ACLF. Bacterial infection was the most common precipitating factor (45%). Kidney failure occurred in 65% of the cases. The 28-day mortality rate was 35% and varied according to ACLF severity at diagnosis, from single organ failure (ACLF-1) at 22% to three organ failures (ACLF-3) at 60%. Eighteen patients (45%) were transplanted with a 100% 28-day survival rate. For ACLF-3 cases at diagnosis (n = 15), the 28-day and 1-year survival rates with a transplant (n = 4) were 100% and 80%, respectively, and without transplant (n = 11), 10 and 0%, respectively. Conclusions: ACLF was associated with high mortality rates. LT was an effective therapeutic option, particularly for ACLF-3 cases.

Resumo Objetivo Avaliar a prevalência de fragilidade e comparar as variáveis associadas a essa fragilidade em pessoas idosas hipertensas comunitárias brasileiras por meio da Escala de Fragilidade de Edmonton (EFE) e o Índice de Vulnerabilidade Clínico-Funcional-20 (IVCF-20). Métodos Trata-se de um estudo transversal e analítico, conduzido com pessoas idosas hipertensas comunitárias com idade ≥60 anos, residentes na cidade de Montes Claros, Minas Gerais, Brasil. A seleção da amostra seguiu o modelo probabilístico por conglomerado. Os dados foram coletados entre novembro de 2016 e fevereiro de 2017 por meio de aplicação de questionário em domicílio. Foram analisadas variáveis demográficas, socioeconômicas e clínico-assistenciais. Utilizou-se a regressão de Poisson com variância robusta para obter as razões de prevalência brutas e ajustadas. Resultados Participaram 281 pessoas idosas hipertensas. A prevalência geral de fragilidade pela EFE foi de 31,3% e pelo IVCF-20 foi de 22,1%. As variáveis, que após a análise múltipla, foram estatisticamente associadas à fragilidade em idosos hipertensos, pela EFE e IVCF-20 simultaneamente, foram: idade avançada (80 anos ou mais), apresentar como comorbidade artrite reumatoide/artrose, acidente vascular encefálico, autopercepção de saúde negativa, quedas e internações nos últimos 12 meses. Apenas pela EFE, menos de 4 anos de estudo, não ter prática religiosa e não possuir renda própria foram as variáveis associadas. Enquanto pelo IVCF-20, somente a renda familiar mensal associou-se à fragilidade. Conclusão Verificou-se que a fragilidade avaliada pela EFE e pelo IVCF-20 possui similaridade, no entanto, a EFE é mais sensível. Esses resultados demonstram a necessidade dos profissionais da saúde identifiquem precocemente a fragilidade.

Abstract Caloric restriction is known to extend the lifespan and/or improve diverse physiological parameters in a vast array of organisms. In the yeast Saccharomyces cerevisiae, caloric restriction is performed by reducing the glucose concentration in the culture medium, a condition previously associated with increased chronological lifespan and 20S proteasome activity in cell extracts, which was not due to increased proteasome amounts in restricted cells. Herein, we sought to investigate the mechanisms through which glucose restriction improved proteasome activity and whether these activity changes were associated with modifications in the particle conformation. We show that glucose restriction increases the ability of 20S proteasomes, isolated from Saccharomyces cerevisiae cells, to degrade model substrates and whole proteins. In addition, threonine 55 and/or serine 56 of the α5-subunit, were/was consistently found to be phosphorylated in proteasomes isolated from glucose restricted cells, which may be involved in the increased proteolysis capacity of proteasomes from restricted cells. We were not able to observe changes in the gate opening nor in the spatial conformation in 20S proteasome particles isolated from glucose restricted cells, suggesting that the changes in activity were not accompanied by large conformational alterations in the 20S proteasome but involved allosteric activation of proteasome catalytic site.

Hydroxyapatite (HAp) is a widely used biocompatible material in orthopedic composite preparations. However, HAp composites that exhibit both anticancer and antibacterial activities through bioactive coordination complexes are relatively rare. To explore orthopedic applications, we blended several silver camphorimine compounds with HAp to create [Ag(I)] composites. All compounds [Ag(NO3)(L)n] (n = 1,2) based on camphorimine (LA), camphor sulfonimine (LB) or imine bi-camphor (LC) ligands demonstrated significant cytotoxic activity (IC50 = 0.30–2.6 μgAg/mL) against osteosarcoma cancer cells (HOS). Based on their structural and electronic characteristics, four complexes (1–4) were selected for antibacterial evaluation against Escherichia coli, Burkholderia contaminans, Pseudomonas aeruginosa, and Staphylococcus aureus. All complexes (1–4) revealed combined anticancer and antibacterial activities; therefore, they were used to prepare [Ag(I)]:HAp composites of 50:50% and 20:80% weight compositions and the activities of the composites were assessed. Results showed that they retain the dual anticancer and antibacterial characteristics of their precursor complexes. To replicate the clinical context of bone-filling applications, hand-pressed surfaces (pellets) were prepared. It is worth highlighting that no agglutination agent was necessary for the pellet’s consistency. The biological properties of the so-prepared pellets were assessed, and the HOS cells and bacteria spreading on the pellet’s surface were analyzed by SEM. Notably, composite 4B, derived from the bicamphor (LC) complex [Ag(NO3)(OC10H14N(C6H4)2NC10H14O)], exhibited significant anticancer activity against HOS cells and antibacterial activity against P. aeruginosa, fostering potential clinical applications on post-surgical OS treatment.

Clinical reasoning is an essential component of nursing. It has emerged as a concept that integrates the core competencies of quality and safety education for nurses. In cooperation with five European partners, Instituto Politécnico de Setúbal (IPS) realized the “Clinical Reasoning in Nursing and Midwifery Education and Practice” project as part of the Erasmus+ project. As a partner, our team designed a multiplier event—the student training course. The aim of this report is to describe the construction and development of this clinical reasoning training course for nursing students. We outline the pedagogical approach of an undergraduate training course on clinical reasoning in 2023, which we separated into four stages: (i) welcoming, (ii) knowledge exploration, (iii) pedagogical learning, and (iv) sharing experience. This paper presents the learning outcomes of the collaborative reflection on and integration of the clinical reasoning concept among nursing students. This educational experience fostered reflection and discussion within the teaching team of the nursing department regarding the concept, models, and teaching/learning methods for clinical reasoning, with the explicit inclusion of clinical reasoning content in the nursing curriculum. We highlight the importance of implementing long-term pedagogical strategies in nursing education.

Considering that buffalo milk is one of the richest in composition, mainly due to its fat fraction, the objective of this research communication was to determine the detailed fatty acid (FA) profile of buffalo milk produced in southern Brazil. Samples were collected from three farms that represent 100% raw buffalo milk producers of dairy products. Properties A and C had only one milking during the lactation period, and farm B had two milking. Farms A and B provided pasture and grain supplements, and farm C, provided only green pasture to the animals. A total of nine FA was identified: six saturated, two monounsaturated, and one polyunsaturated (conjugated linoleic acid - CLA). This study is the first to report the FA profile, including desirable fatty acids (DFA) like monounsaturated, polyunsaturated fatty acids, and stearic acid in buffalo milk from southern Brazil. The farms tested used different food management practices, as well as pasture management, showing that green pasture increases the fatty acid profile in buffalo milk. In addition, buffalo milk represented a good source of DFA for humans and opens a new field for the dairy industry that can explore the control of its FA composition, mainly through feed management.

This study describes the case of a health professional infected first by influenza virus A(H3N2) and then by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 11 days later. Respiratory samples and clinical data were collected from the patient and from close contacts. RNA was extracted from samples and reverse transcription–quantitative polymerase chain reaction (RT-qPCR) was used to investigate the viruses. The patient presented with two different illness events: the first was characterized by fever, chest and body pain, prostration and tiredness, which ceased on the ninth day; RT-qPCR was positive only for influenza virus A(H3N2). Eleven days after onset of the first symptoms, the patient presented with sore throat, nasal congestion, coryza, nasal itching, sneezing and coughing, and a second RT-qPCR test was positive only for SARS-CoV-2; in the second event, symptoms lasted for 11 days. SARS-CoV-2 sequencing identified the Omicron BA.1 lineage. Of the patient’s contacts, one was coinfected with influenza A(H3N2) and SARS-CoV-2 lineage BA.1.15 and the other two were infected only with SARS-CoV-2, one also with Omicron BA.1.15 and the other with BA.1.1. Our findings reinforce the importance of testing for different viruses in cases of suspected respiratory viral infection during routine epidemiological surveillance because common clinical manifestations of COVID-19 mimic those of other viruses, such as influenza.

Abstract The feasibility of using an external beam microprobe facility to explore the biological effects generated by proton irradiation in cultured cells is demonstrated. An in-air irradiation set-up was developed that allows energy tuning and enables estimating the flux and dose deposition in cells. A pilot study on the effect of boron-rich metallacarboranes as radiosensitizers towards human glioblastoma cells was carried out. This served as a proof of concept for the enhancement effect of proton irradiation induced by the presence of boron, which undergoes a nuclear 11B(p,α)αα reaction. Details of the experimental set-up and physical parameters measured are presented. Also, preliminary results of cell’s irradiation and uncertainties are discussed anticipating the advances that have been achieved by our group in this field.

In May 2022, the World Health Organization (WHO) confirmed a multicountry monkeypox virus (MPXV) outbreak caused by MPXV clade II. As of September 14, 2022, 59,147 infections had been described [...]

Resumo Objetivo Comparar os escores do Índice de Vulnerabilidade Clínico-Funcional-20 (IVCF-20) e da Edmonton Frail Scale (EFS) entre pessoas idosas com 80 anos ou mais de idade que vivem na comunidade, considerando a prevalência e o grau de concordância. Método Trata-se de estudo transversal, aninhado a uma coorte de base populacional. A amostragem na linha de base foi probabilística, por conglomerados, em dois estágios. No primeiro, utilizou-se como unidade amostral o setor censitário. No segundo, definiu-se o número de domicílios segundo a densidade populacional de pessoas idosas. Foram determinados a sensibilidade, a especificidade e os valores preditivos. A estatística Kappa analisou o grau de concordância entre os instrumentos. Resultados Foram avaliadas 92 pessoas idosas longevas. A prevalência do alto risco de vulnerabilidade clínico-funcional, considerado pessoa idosa frágil, foi de 45,7% pelo IVCF-20 e a prevalência de fragilidade pela EFS foi de 44,6%. Os valores de sensibilidade, especificidade, valor preditivo positivo e valor preditivo negativo foram, respectivamente, 88,23%, 87,80%, 90,0% e 85,71%. A acurácia foi de 88,04%. A estatística Kappa foi 0,759 (p

We evaluated epidemiologic and molecular characteristics of monkeypox virus (MPXV) infections sampled from 2 healthcare nurses. Five days after collecting samples from an infected patient, the nurses showed typical MPXV manifestations; quantitative PCR and whole-genome sequencing confirmed MPXV infection, most likely transmitted through contact with fomites.

Chronic stress can trigger or worsen motor symptoms in neuropsychiatric disorders. Here, the authors show that SOM interneurons in the striatum are involved in stress-induced motor behaviors.

Resumo Introdução A raiva é uma doença endêmica no Brasil, cuja forma de combate em humanos é a vacinação de animais. Objetivo Buscou-se analisar associação entre fatores sociodemográficos e econômicos de adultos com vacinação antirrábica de animais domésticos com amostra da Pesquisa Nacional de Saúde realizada em 2013. Método Estudo transversal tendo como desfecho vacinação antirrábica de cães e gatos e exposições: sexo, idade, escolaridade, renda per capita e cor da pele autodeclarada do chefe de domicílio. Foram realizadas análises bi e multivariadas por meio de regressão logística. Resultados No Brasil, 59,3% (IC95%59,1-59,5) dos domicílios tinham animal de estimação. Em relação à vacinação antirrábica, a região Sudeste possui a maior prevalência, em que 84,8% (IC95%83,3-86,2) dos domicílios vacinaram todos os cães e gatos, contra 63,7% (IC95%60,9-66,3) na região Sul. Indivíduos com ≥50 anos têm 64% mais chances de vacinar cães e gatos, comparados àqueles na faixa etária mais jovem (18-29 anos). Quanto à escolaridade, indivíduos com ≥12 anos de estudo têm 2,4 vezes mais chances de vacinar todos os animais do domicílio, em relação àqueles com 0-8 anos de estudo. Conclusão Os resultados deste estudo apontam para a necessidade de políticas públicas que orientem a população sobre guarda responsável e que ofertem serviços de imunização.

O estudo teve por objetivo identificar a percepção dos Presidentes, Conselheiros de Administração e Auditores internos acerca das práticas de controle interno em cooperativas de crédito, baseando-se no framework do COSO ICIF 2013. Para tanto, utilizou-se um survey para capturar os contextos institucionais dos respondentes. Os dados foram analisados em conjunto e pelas médias dos grupos, por meio do teste não paramétrico de Kruskal Wallis. Os resultados indicam a existência de práticas de controle interno nas instituições, todavia, não há uniformização conceitual de controle interno. Além disso, as práticas relacionadas aos componentes: Ambiente de controle e atividades de controle, são mais evidentes, todavia, as práticas relacionadas aos demais componentes necessitam de reforço para garantirem o funcionamento constante do sistema de controle interno. No panorama geral, conclui-se que, apesar da divergência conceitual, as cooperativas possuem estruturas de controles internos, sendo corroboradas pela expressiva concordância acerca da implementação de práticas de controle interno.

Aging causes considerable changes in the nervous system, inducing progressive and long-lasting loss of physiological integrity and synaptic plasticity, leading to impaired brain functioning. These age-related changes quite often culminate in behavioral dysfunctions, such as impaired cognition, which can ultimately result in various forms of neurodegenerative disorders. Still, little is known regarding the effects of aging on behavior. Moreover, the identification of factors involved in regenerative plasticity, in both the young and aged brain, is scarce but crucial from a regenerative point of view and for our understanding on the mechanisms that control the process of normal aging. Recently, we have identified the iron-trafficking protein lipocalin-2 (LCN2) as novel regulator of animal behavior and neuronal plasticity in the young adult brain. On the other hand, others have proposed LCN2 as a biological marker for disease progression in neurodegenerative disorders such as Alzheimer’s disease and multiple sclerosis. Still, and even though LCN2 is well accepted as a regulator of neural processes in the healthy and diseased brain, its contribution in the process of normal aging is not known. Here, we performed a broad analysis on the effects of aging in mice behavior, from young adulthood to middle and late ages (2-, 12-, and 18-months of age), and in the absence of LCN2. Significant behavioral differences between aging groups were observed in all the dimensions analyzed and, in mice deficient in LCN2, aging mainly reduced anxiety, while sustained depressive-like behavior observed at younger ages. These behavioral changes imposed by age were further accompanied by a significant decrease in cell survival and neuronal differentiation at the hippocampus. Our results provide insights into the role of LCN2 in the neurobiological processes underlying brain function and behavior attributed to age-related changes.

Accreditation processes for health care professions are designed to ensure that individuals and programs in these fields meet established standards of quality and effectiveness. The accelerating pace of globalization in the health care professions has increased the need for a shared understanding of the vocabulary of evaluation, assessment, and accreditation. The psychometric principles of valid and reliable assessment are commonly accepted, but the terminology is confusing. We believe that all stakeholders – evaluators, faculty, students but also the community – will benefit from a shared language and common set of definitions. We recognize that not all readers will agree with the definitions we propose, but we hope that this guide will help to ensure clarity, consistency, transparency, and fairness, and that it will promote through the stimulation of a debate greater collaboration across national and international boundaries.

Resumo Objetivo analisar a prevalência de multimorbidade em idosos e seus fatores associados. Método estudo transversal, parte de uma coorte de base populacional, realizado em Montes Claros, Minas Gerais, Brasil. Realizou-se uma amostragem probabilística, por conglomerados, em dois estágios: por setor censitário e por domicílios, segundo a densidade populacional de idosos. A variável dependente foi a multimorbidade, considerando o acúmulo simultâneo de duas ou mais e três ou mais doenças crônicas em idosos comunitários. Foram estimadas as razões de prevalência por meio da regressão de Poisson, com variância robusta. Resultado: a prevalência de multimorbidade em idosos, com duas ou mais e três ou mais doenças crônicas, foi de 67,8% e 43,4%, respectivamente. Após análise múltipla, o sexo feminino (RPaj=1,15; IC95% 1,04-126)/(RPaj=1,19; IC95%108-1,31), a fragilidade (RPaj=1,15; IC95%1,05-1,27)/(RPaj= 1,28; IC95% 1,16-1,41) e a realização de consulta médica nos últimos 12 meses (RPaj=1,25; IC95%1,06-1,47)/(RPaj=1,22; IC95% 1,06-1,41) relacionaram-se à multimorbidade, tanto com duas ou mais, quanto com três ou mais doenças crônicas, respectivamente. A autopercepção de saúde ruim (RPaj=1,20; IC95%1,09-1,32) associou-se à multimorbidade com duas ou mais doenças crônicas, enquanto não possuir plano de saúde particular (RPaj=1,14; IC95%1,04-1,25) foi associado à multimorbidade com três ou mais doenças crônicas. Conclusão A prevalência de multimorbidade foi alta em idosos comunitários, considerando duas ou mais e três ou mais doenças crônicas. O conhecimento dessas condições pode auxiliar nas ações de promoção, prevenção e vigilância em saúde de idosos comunitários.

Lipocalin-2 (LCN2) is an acute phase protein able to bind iron when complexed with bacterial siderophores. The recent identification of a mammalian siderophore also suggested a physiological role for LCN2 in the regulation of iron levels and redox state. In the central nervous system, the deletion of LCN2 induces deficits in neural stem cells proliferation and commitment, with an impact on the hippocampal-dependent contextual fear discriminative task. Additionally, stress is a well-known regulator of cell genesis and is known to decrease adult hippocampal cell proliferation and neurogenesis. Although voluntary running, another well-known regulator of neurogenesis, is sufficient to rescue the defective hippocampal neurogenesis and behavior in LCN2-null mice by promoting stem cells’ cell cycle progression and maturation, the relevance of LCN2-regulated hippocampal neurogenesis in response to stress has never been explored. Here, we show a lack of response by LCN2-null mice to the effects of chronic stress exposure at the cellular and behavioral levels. Together, these findings implicate LCN2 as a relevant mediator of neuronal plasticity and brain function in the adult mammalian brain.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system that presents a largely unknown etiopathology. The presence of reactive astrocytes in MS lesions has been described for a long time; however, the role that these cells play in the pathophysiology of MS is still not fully understood. Recently, we used an MS animal model to perform high-throughput sequencing of astrocytes’ transcriptome during disease progression. Our data show that astrocytes isolated from the cerebellum (a brain region typically affected in MS) showed a strong alteration in the genes that encode for proteins related to several metabolic pathways. Specifically, we found a significant increase in glycogen degradation, glycolytic, and TCA cycle enzymes. Together with these alterations, we detected an upregulation of genes that characterize “astrocyte reactivity”. Additionally, at each disease time point we also reconstructed the morphology of cerebellum astrocytes in non-induced controls and in EAE animals, near lesion regions and in the normal-appearing white mater (NAWM). We found that near lesions, astrocytes presented increased length and complexity compared to control astrocytes, while no significant alterations were observed in the NAWM. How these metabolic alterations are linked with disease progression is yet to be uncovered. Herein, we bring to the literature the hypothesis of performing metabolic reprogramming as a novel therapeutic approach in MS.

Piano-stool-{CpRu} complexes containing 1,3,5-triaza-7-phosphaadamantane (PTA), N-methyl-1,3,5-triaza-7-phosphaadamantane (mPTA), and 3,7-dimethyl-1,3,7-triaza-5-phosphabyciclo[3.3.1]nonane (dmoPTA) were evaluated as drugs against breast cancer. The evaluated compounds include two new examples of this family, the complexes [RuCp(DMSO-κS)(HdmoPTA)(PPh3)](CF3SO3)2 (8) and [RuCp(PPh3)2-µ-dmoPTA-1κP-2κ2N,N′-PdCl2](CF3SO3) (11), which have been synthesized and characterized by NMR, IR, and single-crystal X-ray diffraction. The cytotoxic activity of compounds was evaluated against MDA-MB-231 breast cancer cells, and the three most active complexes were further tested against the hormone-dependent MCF-7 breast cancer cell line. Their cell death mechanism and ruthenium uptake were also evaluated, as well as their binding ability to human serum albumin.

Abstract Background Malocclusion is a condition frequently seen in primary dentition due to the interaction of environmental, genetic and behavioural factors. The occurrence of some types of malocclusions can have an impact on oral health-related quality of life in children. Hence, the present study aimed to verify the impact of primary dentition malocclusion on oral health-related quality of life in preschool children. Methods A population-based cross-sectional study was conducted in Florianopolis, Brazil, with a representative sample of 1050 preschoolers aged between 2 and 5 years, randomly selected. Parents answered the Brazilian version of the Early Childhood Oral Health Impact Scale and also to a questionnaire on socio-economic indicators. Data obtained from the questionnaire were obtained by item response theory based on model of gradual response. The malocclusion assessed was: anterior open bite, increased overjet and posterior crossbite. Poisson regression model was employed for multivariate analysis (P