Antiviral and immunological activity of zinc and possible role in COVID-19.

Zn deficiency compromises its biological functions, its effect on the immune system and its antiviral activity, increasing vulnerability to infectious diseases. This narrative review aims at presenting and discussing functional aspects and possible mechanisms involved in the potential role of Zn in the immune response and antiviral activity for coronavirus infectious disease-19 (COVID-19) prevention and control. The searches were conducted in PubMed and Science Direct databases, using clinical trials, experimental studies in animals and humans, case-control studies, case series, letters to the editor, and review articles published in English, without restrictions on year of publication. Search approach was based on using the terms: 'zinc', 'COVID-19', 'antiviral agents', 'immunologic factors' and 'respiratory tract infections'. Literature shows the importance of Zn as an essential mineral immunomodulator with relevant antiviral activity in the body. Thus, although there is still a scarcity of studies evaluating Zn supplementation in patients with COVID-19, the results on the topic show the necessity of controlling Zn mineral deficiency, as well as maintaining its homoeostasis in the body in order to strengthen the immune system and improve the prevention of highly complex viral infections, such as that of the COVID-19.

Feelings reported by adolescents after food ingestion: a comparative study / Sentimentos relatados por adolescentes após a ingestão alimentar: um estudo comparativo

INTRODUCTION: Food is closely linked with emotions in a complex relationship. The imaginary and symbolic meaning attributed to food has been little studied and the act of eating needs to be better understood. OBJECTIVE: To analyze the association of adolescents´ feelings to selected foods. METHODS: Cross-sectional study with 995 adolescents from public and private schools in Teresina, PI, Brazil. It was a Supplementary Project to the Brazilian national survey ERICA (Estudo de Riscos Cardiovasculares em Adolescentes). Adolescents had to choose one of the following feelings to selected food: well-being/satisfaction, malaise, no feeling, aversion. For the option aversion, the participant had to indicate if it was related to smell, color, appearance, or taste. Adolescents´ feelings to foods were analyzed by type of school, sex, and age range, using Pearson's chi-square (χ²) or Fisher's exact tests. RESULTS: There was significant differences regarding the type of school for the feeling to chocolate (p=0.015); vegetables (p=0.003); leafy greens (p=0.005); healthy sandwich/natural fruit juice (p≤0.001); high fat red meat (p=0.046); fruit/natural fruit juice (p≤0.001). For sex, there was significant difrerences for healthy sandwich/natural fruit juice (p=0.001); beans and rice (p=0.021) and high fat red meat (p=0.005). There was significant differences between age groups for sandwich, chips, soda and ice cream (p=0.018); pasta (p=0.047) and high fat red meat (p=0.021). Well-being predominated in almost all foods and aversion was poorly reported. CONCLUSION: The results suggest that adolescents' feelings are not directed to specific foods.

INTRODUÇÃO: O alimento está intimamente ligado com as emoções em uma relação complexa. O sentido imaginário e simbólico atribuído à alimentação tem sido pouco estudado e o ato de comer precisa ser melhor compreendido. OBJETIVO: Avaliar a associação de sentimentos dos adolescentes relacionados a alimentos selecionados. MÉTODO: Estudo transversal com 995 adolescentes de escolas públicas e privadas de Teresina, PI, Brasil. Os dados foram provenientes do Projeto Suplementar ao levantamento nacional brasileiro ERICA (Estudo de Riscos Cardiovasculares em Adolescentes). O adolescente teve que escolher um dos seguintes sentimentos para o alimento selecionado: bem-estar/satisfação, desconforto, nenhum sentimento ou aversão. Para a opção aversão, o participante deveria indicar se ela estava relacionada ao cheiro, cor, aparência ou sabor. Os sentimentos dos adolescentes em relação aos alimentos foram analisados ​​por tipo de escola, sexo e faixa etária, por meio do teste qui-quadrado de Pearson (c²) ou teste exato de Fisher. RESULTADOS: Houve diferenças significativas entre os tipos de escola para o sentimento em relação ao chocolate (p=0,015); legumes/verduras (p=0,003); folhosos (p=0,005); sanduiche/suco natural (p≤0,001); carne vermelha gordurosa (p=0,046); fruta/suco natural (p≤0,001). Para o sexo, houve diferença significativa para sanduiche/suco natural (p=0,001); arroz com feijão (p=0,021) e carne vermelha gordurosa (p=0,005). Para a faixa etária, houve diferença significativa para sanduíche, batata frita, refrigerante e sorvete (p=0,018); macarrão (p=0,047) e carne vermelha gordurosa (p=0,021). O bem-estar predominou em quase todos os alimentos e a aversão foi pouco relatada. CONCLUSÃO: Os resultados sugerem que os sentimentos dos adolescentes não estão direcionados a um alimento específico.

Vitamin B12, bone mineral density and fracture risk in adults: A systematic review / Vitamina B12, densidade mineral óssea e risco de fraturas em adultos: uma revisão sistemática

Summary Objective: To consolidate information available on the effect of vitamin B12 on bone mineral density and fracture risk, with emphasis on clinical trials, observational and longitudinal data conducted in humans. Method: A systematic review of the literature of the past decade on the role of vitamin B12 in bone mineral density and fracture risk in subjects of all ages and both sexes was performed by means of a PubMed, Science Direct, Medline and SciELO database search. Articles included in this review were identified using the search terms: B12 Vitamin and Bone Mineral Density and Vitamin B12 and Risk of Fractures. Evidence quality of the included articles was evaluated by GRADE system. Results: A total of 25 original studies were identified. After reviewing the titles and abstracts of articles, only 17 articles met the inclusion criteria. The present review provides evidence that the role of vitamin B12 on bone mineral density or fracture risk should be further elucidated. Controversies are explained by heterogeneity of methodologies used for the diagnosis of vitamin B12 and also by differences among populations investigated on the studies. Conclusion: A real effect of vitamin B12 deficiency in bone health and the mechanisms associated with bone metabolism is not well established yet. It is extremely important to carry out more clarifying studies about this theme, especially with vulnerable groups such as postmenopausal and elderly women, as is well-known that they are greatly affected by deficiency of this vitamin.

Resumo Objetivo: Consolidar as informações disponíveis acerca dos efeitos da vitamina B12 sobre a densidade mineral óssea e o risco de fraturas, com destaque para ensaios clínicos, dados observacionais e longitudinais realizados com humanos. Método: Foi realizada uma revisão sistemática da literatura dos últimos dez anos sobre o papel da vitamina B12 na densidade mineral óssea e no risco de fraturas em populações de todas as idades e para ambos os sexos, com busca de artigos nos bancos de dados eletrônicos: PubMed, Science Direct, Medline e SciELO. Como estratégia de busca de dados incluíram-se os descritores: B12 Vitamin and Bone Mineral Density e B12 Vitamin and Risk of Fractures. A qualidade das evidências dos artigos incluídos foi avaliada pelo sistema GRADE. Resultados: Após a análise dos títulos e dos resumos dos artigos, a estratégia de busca resultou em 25 referências, das quais 17 artigos preencheram os critérios de elegibilidade. Esta revisão fornece evidências de que o papel da vitamina B12 sobre a densidade mineral óssea ou o risco de fraturas ainda precisa ser mais bem elucidado. As controvérsias encontram respaldo na heterogeneidade das metodologias utilizadas para o diagnóstico da vitamina B12 e também na variedade de populações presentes entre os estudos. Conclusão: Ainda não está bem estabelecido o real impacto da deficiência de vitamina B12 na saúde dos ossos e sobre os mecanismos associados ao metabolismo ósseo. É de suma importância a realização de mais estudos esclarecedores, principalmente em grupos vulneráveis como as mulheres pós-menopausa e os idosos, grupos estes bastante afetados pela deficiência dessa vitamina.

Vitamin B12, bone mineral density and fracture risk in adults: A systematic review.

OBJECTIVE: To consolidate information available on the effect of vitamin B12 on bone mineral density and fracture risk, with emphasis on clinical trials, observational and longitudinal data conducted in humans. METHOD: A systematic review of the literature of the past decade on the role of vitamin B12 in bone mineral density and fracture risk in subjects of all ages and both sexes was performed by means of a PubMed, Science Direct, Medline and SciELO database search. Articles included in this review were identified using the search terms: B12 Vitamin and Bone Mineral Density and Vitamin B12 and Risk of Fractures. Evidence quality of the included articles was evaluated by GRADE system. RESULTS: A total of 25 original studies were identified. After reviewing the titles and abstracts of articles, only 17 articles met the inclusion criteria. The present review provides evidence that the role of vitamin B12 on bone mineral density or fracture risk should be further elucidated. Controversies are explained by heterogeneity of methodologies used for the diagnosis of vitamin B12 and also by differences among populations investigated on the studies. CONCLUSION: A real effect of vitamin B12 deficiency in bone health and the mechanisms associated with bone metabolism is not well established yet. It is extremely important to carry out more clarifying studies about this theme, especially with vulnerable groups such as postmenopausal and elderly women, as is well-known that they are greatly affected by deficiency of this vitamin.

Effect of magnesium supplementation on insulin resistance in humans: A systematic review.

OBJECTIVES: Recent studies have demonstrated that minerals play a role in glucose metabolism disorders in humans. Magnesium, in particular, is an extensively studied mineral that has been shown to function in the management of hyperglycemia, hyperinsulinemia, and insulin resistance (IR) action. The aim of this study was to investigate the effect of magnesium supplementation on IR in humans via systematic review of the available clinical trials. METHODS: This review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. A survey was conducted to select clinical trials related to the effects of this mineral in insulin sensitivity using the following databases: PubMed, SciVerse Scopus, ScienceDirect, and SciVerse Cochrane. RESULTS: After the selection process, 12 articles were identified as eligible, representing different clinical conditions and being free of restriction with regard to sex, age, ethnicity, and differential dosing/shape of magnesium. The results of eight clinical trials showed that supplementation with magnesium influences serum fasting glucose concentrations, and five trials determined an effect on fasting insulin levels. The results of seven studies demonstrated that mineral supplementation reduced homeostasis model assessment for IR values. CONCLUSIONS: The data of this systematic review provide evidence as to the benefits of magnesium supplementation in reducing IR in patients with hypomagnesemia presenting IR. However, new intervention studies are needed to elucidate the role of the nutrient in protection against this metabolic disorder, as well as the standardization of the type, dose, and time of magnesium supplementation.

High 15-F2t-Isoprostane Levels in Patients with a Previous History of Nonmelanoma Skin Cancer: The Effects of Supplementary Antioxidant Therapy.

BACKGROUND: Phase I of this study was aimed at comparing the profiles of oxidative stress biomarkers in patients with history of nonmelanoma skin cancer (NMSC), previously treated with surgery, to the healthy subjects. Phase II aimed to evaluate the effects of supplementary antioxidant therapy on the levels of biomarkers in the case group. MATERIALS AND METHODS: In Phase I, oxidative stress biomarkers were measured in blood samples obtained from 24 healthy subjects and 60 patients with history of NMSC previously treated with surgery. In Phase II, the 60 patients with history of NMSC were randomized into two subgroups, one receiving placebo (n = 34) and the other (n = 26) receiving vitamin C, vitamin E, and zinc supplementation for 8 weeks, followed by reevaluation of biomarkers. RESULTS: In Phase I, patients with history of NMSC showed increased plasma concentrations of all biomarkers, but only 15-F2t-isoprostane was significantly higher than in the healthy subjects. Risk of NMSC increased by 4% for each additional 1 pg/mL increase in 15-F2t-isoprostane. In Phase II, supplementation did not significantly reduce levels of oxidative stress biomarkers. CONCLUSION: Patients with history of NMSC had significantly high 15-F2t-isoprostane plasma levels; supplementation did not result in significant reduction of oxidative stress biomarkers. This trial was registered with ClinicalTrials.gov (ID NCT02248584).