Effects of the excessive use of electronic screens on vision and emotional state / Efeitos do uso excessivo de telas eletrônicas na visão e no estado emocional

ABSTRACT Objective To investigate relations between electronic screen use and eye health in a representative sample of the Brazilian population. Methods Data were collected online and analyzed at a private Brazilian hospital (Provisão Hospital, Maringá, Brazil). Male and female individuals aged 12 to 35 years participated in the study. A population-based cross-sectional survey based on a questionnaire developed using the Google Forms interface was carried out. The questionnaire was answered anonymously in order to ensure the confidentiality of data and the privacy of participants. Data were collected between October 13, 2020, and January 30, 2021. Results A total of 200 questionnaires were completed. Most responders were young people aged 18 to 27 years. Daily electronic device use time reported by responders ranged from more than 5 hours (150; 75.5%) to 3 to 5 hours/day (28; 14%) or 2 to 3 hours/day (16; 8%). Only a small proportion of responders (2.5%) used these devices less than 1 hour per day. Most participants had myopia (164; 84%) and/or astigmatism (151; 75.5%), whereas keratoconus was less prevalent (34; 17%). However, 92 participants were unable to say whether they had these diseases or not. Most participants reported eye symptoms after screen use (red eyes, fatigue, dry and gritty eyes and blurred vision). Mental issues such as smartphone dependence and difficulties to communicate while using electronic devices were also addressed. Most responders reported dependence and communication problems. Conclusions Most young people in this sample had sings of eye disease, including keratoconus. Smartphone dependence and addition was also observed. Findings presented may inform future studies and help health authorities to properly guide public health strategies aimed at eye disease prevention.

RESUMO Objetivo Investigar o uso de telas na saúde ocular em uma amostra populacional brasileira. Métodos Os dados foram adquiridos on-line, e as análises foram realizadas em uma clínica privada na Região Sul do Brasil. Os participantes foram indivíduos de 12 a 35 anos, de ambos os sexos. Foi realizada pesquisa transversal de base populacional por meio de questionário elaborado na plataforma Google Forms. O questionário foi respondido de forma anônima, mantendo o sigilo dos dados coletados e a privacidade dos participantes. A coleta de dados teve início em 13 de outubro de 2020 e término em 30 de janeiro de 2021. Resultados Foram respondidos 200 questionários. A maioria foi de jovens entre 18 e 27 anos. O tempo de uso de dispositivos eletrônicos durante o dia foi de mais de 5 horas para 150 (75,5%) entrevistados, 28 (14%) gastavam de 3 a 5 horas por dia, 16 (8%) de 2 a 3 horas por dia e uma pequena parte dos entrevistados (2,5%) usava menos de 1 hora por dia. A maioria dos participantes tinha miopia (164; 84%) e/ou astigmatismo (151; 75,5%). Ceratocone foi menos prevalente (34; 17%), entretanto 92 pessoas não sabiam a resposta. A maioria dos participantes teve problemas nos olhos após o uso da tela, como olhos vermelhos, cansados e secos, além de visão turva. Questões mentais, como dependência de smartphones e dificuldade de comunicação durante o uso do dispositivo, também foram abordadas. A maioria dos entrevistados demonstrou dependência e problemas de comunicação. Conclusões A maior parte dos jovens apresentou quadro de doenças oculares, incluindo ceratocone. Dependência e adição de smartphone também foram observados. Esses resultados apoiam a identificação de fatores associados à patologia ocular, servindo de base para estudos futuros, e podem auxiliar às autoridades de saúde no direcionamento adequado das atividades de prevenção e controle em saúde pública.

Morphologic study of the effect of iron on pseudocyst formation in Trichomonas vaginalis and its interaction with human epithelial cells

BACKGROUND Trichomonas vaginalis is the aetiological agent of human trichomoniasis, which is one of the most prevalent sexually transmitted diseases in humans. Iron is an important element for the survival of this parasite and the colonisation of the host urogenital tract. OBJECTIVES In this study, we investigated the effects of iron on parasite proliferation in the dynamics of pseudocyst formation and morphologically characterised iron depletion-induced pseudocysts. METHODS We performed structural and ultrastructural analyses using light microscopy, scanning electron microscopy and transmission electron microscopy. FINDINGS It was observed that iron depletion (i) interrupts the proliferation of T. vaginalis, (ii) induces morphological changes in typical multiplicative trophozoites to spherical non-proliferative, non-motile pseudocysts, and (iii) induces the arrest of cell division at different stages of the cell cycle; (iv) iron is the fundamental element for the maintenance of typical trophozoite morphology; (v) pseudocysts induced by iron depletion are viable and reversible forms; and, finally, (vi) we demonstrated that pseudocysts induced by iron depletion are able to interact with human epithelial cells maintaining their spherical forms. MAIN CONCLUSIONS Together, these data suggest that pseudocysts could be induced as a response to iron nutritional stress and could have a potential role in the transmission and infection of T. vaginalis.