Efeitos da deficiência de cobre, zinco e magnésio sobre o sistema imune de crianças com desnutrição grave

Macrominerals and Trace Minerals in Commercial Infant Formulas Marketed in Brazil: Compliance With Established Minimum and Maximum Requirements, Label Statements, and Estimated Daily Intake

Infant formulas are the main nutritional source for infants when breastfeeding is not possible or recommended. The daily need for specific nutrients, such as essential minerals, in early stages of a child's life is high because of rapid infant growth and development, which impose metabolic flux increases on these pathways to support growth, physical activity, and defense against infections. In this context, this research aimed to determine macromineral and trace mineral contents in starting (phase 1) and follow-up (phase 2) infant formulas marketed in Brazil (n = 30) by inductively coupled plasma-mass spectrometry, calculate estimated daily intakes, and compare them to reference values regarding adequate intake and tolerable upper intake levels. The highest concentrations of macrominerals were observed in Ca, K, P, and Na, and trace minerals in Fe, Zn, Mn, and Cu. Certain homogeneity only to trace mineral contents was observed when analyzing inter-batch values from same manufacturers. In general, all phase 1 and phase 2 infant formula brands and batches met or exceeded Fe, Zn, Cu, Mo, and Se contents when compared to maximum limits established by Codex Alimentarius. In addition, Zn contents in eight phase 1 and in four phase 2 infant formulas were above the contents established by the tolerable upper intake level for children aged 0–6 and/or 7–12 months, respectively. These findings highlight the need to expand regular infant formula inspection concerning nutritional quality, as some composition aspects of these foods must be improved to follow international guidelines, since ideal requirements for infant formula composition, quality, and safety interfere in child development and adult health.

Dynamics of plasma micronutrient concentrations and their correlation with serum proteins and thyroid hormones in patients with paracoccidioidomycosis

Minerals, such as zinc, copper, and iron are reported to play roles in chronic infectious diseases; however, their role in paracoccidioidomycosis (PCM) remains unknown. This study aimed to examine the micronutrient dynamics and their correlation with serum proteins and thyroid hormones in patients with PCM. In 14 patients with PCM and 10 healthy subjects, we evaluated the body mass index (BMI) along with serum levels of hemoglobin, iron, ferritin, zinc, copper, magnesium, albumin, globulin, thyroid stimulating hormone (TSH), thyroxine (free T4), and triiodothyronine (T3). Evaluations were conducted at the first appointment, before treatment, and at the end of the first, second, fourth, and sixth month of PCM treatment. The control group was only evaluated once. We observed that before treatment, patients with PCM, had higher levels of copper and lower level of iron than those of the control group. After one month of treatment, the iron levels increased, whereas the levels of copper after six months of treatment. Reduction in inflammatory activity, indicated by the normalization of C-reactive protein, ferritin, albumin, and globulin levels, was observed during treatment. However, no correlation was observed between the serum levels of minerals and inflammatory activity or thyroid function in this study. In conclusion, our results showed higher serum copper levels in control group compared to those in pretreatment patients; the clinical importance of this observation should be investigated in further studies. After treatment, serum copper levels showed a tendency to decrease. In addition, serum iron levels were decreased at the stage of active disease, and were increased after treatment. Thus, serum iron levels can be used as a better biomarker for treatment control.

Brazilian studies on zinc deficiency and supplementation: emphasis on children

Abstract Objectives: to review the literature of studies developed in Brazil on zinc deficiency and the effects of supplementation. Methods: a literature review based on bibliographic research was carried out in SciELO, LILACS and MEDLINE/PUBMED databases. A total of 133 studies on zinc deficiency and 116 on the effects of supplementation were identified. Thirty-two articles, 16 of which were observational and 16 interventional, were analyzed. Results: the studies focused mainly on children (75.0% of the observational and 81.25% of the experimental studies). Biochemical deficiency of zinc in children presented great variability, from 0.0% to 74.3%, with expressive prevalence in most studies. Dietary inadequacy among children presented variability from 16.6% to 46.0%. Five from seven studies showed a positive effect of zinc supplementation on micronutrient nutritional status. Conclusions: there is evidence of zinc deficiency in children as a public health problem, preventable through micronutrient supplementation.

Magnesium Status and Its Relationship with C-Reactive Protein in Obese Women

This study assessed the relationship between magnesium status and C-reactive protein concentration in obese and nonobese women. This cross-sectional study included 131 women, aged between 20 and 50 years, who were divided into two groups: obese (n=65) and control (n=66) groups. Magnesium intake was monitored using 3-day food records and NutWin software version 1.5. The plasma, erythrocyte, and urinary magnesium concentrations were determined by flame atomic absorption spectrophotometry. C-reactive protein concentration in serum was measured by immunoturbidimetric assay. The mean values of the magnesium content in the diet were lower than those recommended, though there was no significant difference between groups (p>0.05). The mean concentrations of plasma and erythrocyte magnesium were within the normal range, with no significant difference between groups (p>0.05). Urinary excretion of this mineral was less than the reference values in both groups, with no significant difference (p>0.05). The mean concentration of serum C-reactive protein was within the normal range in both groups, with no significant difference (p>0.05). There was a positive correlation between urinary magnesium and serum C-reactive protein (p=0.015). Obese patients ingest low dietary magnesium content, which seems to induce hypomagnesuria as a compensatory mechanism to keep plasma concentrations of the mineral at adequate levels. The study shows a positive correlation between urinary magnesium concentrations and serum C-reactive protein, suggesting the influence of hypomagnesuria on this inflammatory protein in obese women.

[Infectious diseases among Brazilian preschool children attending daycare centers]

The scope of this article is to analyze the prevalence and factors associated with the development of infectious diseases that affect children in daycare centers, namely respiratory infections, diarrheal disease and parasitic infections. Bibliographic research was conducted in the MEDLINE, LILACS and SciELO databases, and observational studies were included. 129 studies were identified, of which 21 were considered relevant to this study, namely two longitudinal and 19 cross-sectional studies. The systematization of the reviewed studies highlighted: i) the presence of intestinal parasites was the main outcome analyzed, followed by respiratory infections; ii) only one study investigated the occurrence of diarrheal disease; iii) the Giardia lamblia was the most prevalent parasitosis; iv) the variables that were most often associated with the development of intestinal parasitosis were child age, family income and maternal education; v) the attendance at daycare centers was a risk factor for intestinal parasites and respiratory infections. Respiratory and parasitic infections are major problems in institutionalized children in daycare centers. The reduction of such diseases involves a complex web of socio-economic, sanitation and daycare center infrastructure aspects.

Estresse oxidativo e micronutrientes na hanseníase

Objetivo Avaliar o estresse oxidativo, perfil antioxidante e de micronutrientes em pacientes portadores de hanseníase multibacilar e paucibacilar antes do tratamento poliquimioterápico. Métodos Analisaram-se 52 amostras de soro de pacientes portadores de hanseníase - 38 multibacilares e 14 paucibacilares -, usuários do ambulatório de dermatologia de um hospital público universitário, além de 30 amostras controles. Quantificaram-se marcador de peroxidação lipídica malondialdeído pelo método de substâncias reativas ao ácido tiobarbitúrico, antioxidante glutationa reduzida pelo método baseado na quantificação de tiol solúvel em ácido, antioxidante vitamina E por cromatografia líquida de alta eficiência, minerais selênio, zinco, cobre, magnésio por espectrometria de massa com fonte plasma acoplado, e sorologia do anticorpo glicolipídio fenólico I pelo método Enzyme-Linked Immunosorbent Assay. Foi utilizado teste não paramétrico de Mann-Whitney para comparar as variáveis quantificadas neste estudo entre os diferentes grupos, e correlação de Pearson para verificar associação dessas variáveis com o anticorpo. O critério de significância adotado foi de p<0,05. Resultados Houve diferença significativa para o malondialdeído (p<0,001) e vitamina E (p<0,001) no grupo controle comparado aos grupos com hanseníase, multibacilar e paucibacilar. No entanto, essas mesmas variáveis não diferiram entre os grupos multibacilar e paucibacilar (p=0,495 e p=0,920 respectivamente). A glutationa reduzida foi superior no grupo controle em relação ao grupo com hanseníase (p=0,012) e multibacilar (p=0,001), no entanto não diferiu do grupo paucibacilar (p=0,920). Quando comparada com os multibacilares e paucibacilares, a glutationa reduzida também não diferiu (p=0,063). Quanto aos minerais, todos se apresentaram dentro da normalidade, exceto o magnésio, cujos níveis foram deficientes em todos os pacientes do estudo. Não foi possível observar correlação do anticorpo glicolipídio fenólico I com as demais variáveis. Conclusão Os pacientes paucibacilares parecem possuir maior defesa antioxidante de glutationa reduzida, semelhante à de indivíduos saudáveis. Baixos níveis de vitamina E nos pacientes com hanseníase são sugestivos dos benefícios de suplementação. As alterações metabólicas observadas não evidenciaram relação com a sorologia do glicolipídio fenólico I.

Effect of neonatal malnutrition on expression of nitric oxide synthase enzyme, production of free radicals and in vitro viability of alveolar macrophages infected with methicillin-sensitive and methicillin-resistant Staphylococcus aureus

OBJECTIVE

Evaluate the effects of neonatal malnutrition on the microbicidal response and viability of in vitro macrophages infected with Staphylococcus aureus sensitive/resistant to methicillin.

METHODS

Male Wistar rats (n = 24) were divided into two distinct groups: nourished (rats breast-fed by mothers undergoing diet with 17% casein) and malnourished (rats breast-fed by mothers undergoing diet with 8% casein). Macrophages were recovered after surgical tracheostomy procedure by collecting bronchoalveolar lavage. Four systems were established: negative control, composed only by phagocytes; positive control, macrophages plus lipopolysaccharide; and two test systems, macrophages plus Staphylococcus aureus sensitive and resistant to methicillin. Plates were incubated at 37 °C for 24 h. After this period, tests for the analysis of cell viability and microbicidal response were performed. In the statistical analysis, the Student's t and ANOVA tests were used, accepting p < 0.05.

RESULTS

The neonatal malnutrition impaired the animals' body weight. There was a lower expression of the inducible nitric oxide enzyme (iNOS), nitric oxide production, and viability of macrophages infected with methicillin-resistant Staphylococcus aureus. However, increased production of superoxide anion in the malnourished group was detected.

CONCLUSION

Neonatal malnutrition focusing on critical periods of development promoted lower expression of iNOS, nitric oxide production, cell viability, and exacerbated reactive oxygen species production. The high levels of reactive oxygen species may favor the onset of serious and systemic infections with fatal outcome if associated with methicillin-resistant Staphylococcus aureus.

Evidências do impacto da suplementação múltipla com micronutrientes no crescimento de pré-escolares: revisão sistemática

Objetivos: agregar evidências sobre o efeito da suplementação múltipla com micronutrientes no crescimento de crianças pré-escolares, com ênfase nos efeitos combinados ou isolados do zinco, ferro e vitamina A. Métodos: foi realizada uma busca por ensaios clínicos aleatorizados e artigos de revisão sistemática com metanálise na base de dados PubMed. Foram selecionados artigos publicados entre 1995 e maio de 2013, considerando a combinação dos descritores (child, preschool OR infant) AND (growth) AND (zinc AND iron AND vitamin A) OR (zinc AND iron) OR (zinc AND vitamin A) OR (iron AND vitamin A). Resultados: foram selecionados 33 artigos para a presente revisão, 29 do tipo ensaio clínico e quatro de revisão sistemática com metanálise. A administração de suplementos nutricionais contendo combinações de zinco, ferro e vitamina A pode aumentar o potencial de crescimento das crianças, sendo mais evidente o efeito quando comparada a suplementação com múltiplos micronutrientes vs placebo ou dieta habitual, e com os esquemas de suplementação dupla e única. A combinação de zinco e vitamina A é a melhor opção de suplementação dupla. O efeito da suplementação tripla em relação às outras opções (placebo, única, dupla, múltipla), bem como os possíveis efeitos diferenciados da suplementação segundo a condição nutricional e/ou idade das crianças, ainda precisam de investigação mais aprofundada para orientar as estratégias de prevenção. Conclusões: a suplementação múltipla com micronutrientes tem efeitos positivos no crescimento linear que dependem do esquema de suplementação adotado.

Avaliação de desempenho das concentrações capilares de zinco como método diagnóstico da deficiência de zinco: um estudo comparativo com as concentrações séricas de zinco

OBJETIVO: Examinar o poder diagnóstico de deficiência de zinco das concentrações capilares desse mineral por meio da comparação com as concentrações séricas. MÉTODOS: Estudo transversal desenvolvido com 170 crianças na faixa etária dos 12 aos 72 meses. A análise da Curva Característica de Operação do Receptor foi utilizada para identificar a sensibilidade e a especificidade do melhor ponto de corte para o diagnóstico da deficiência de zinco no cabelo. Verificou-se ainda a significância estatística da área sob a curva. RESULTADOS:O ponto de corte apontado como ótimo para o zinco no cabelo foi de 292,52ppm (sensibilidade de 55,6% e especificidade de 60,8%), com uma área sob a curva de 0,549, sem significância estatística. CONCLUSÃO: O diagnóstico da deficiência de zinco pelas concentrações capilares desse elemento, em comparação às concentrações séricas de zinco, mostra baixa sensibilidade e ponto de corte ideal superior ao sugerido. Permanece, ainda, a necessidade de novos estudos que possibilitem a obtenção de indicadores bioquímicos mais sensíveis e específicos para o diagnóstico da deficiência de zinco na população, sob tudo sem importantes limitações técnicas.

Consumo alimentar entre crianças brasileiras de dois a cinco anos de idade: Pesquisa Nacional de Demografia e Saúde (PNDS), 2006

O objetivo deste estudo foi descrever características do consumo alimentar de crianças brasileiras e sua associação com fatores sociodemográficos. Foram analisados os dados de consumo alimentar da Pesquisa Nacional de Demografia e Saúde da Criança e da Mulher realizada em 2006. A análise considerou a complexidade amostral e incluiu 3.083 crianças de dois a cinco anos de idade. O desfecho foi avaliado a partir de marcadores alimentares. As estimativas desses marcadores foram descritas segundo sexo e idade da criança, local de residência, idade e escolaridade materna. Nas análises estatísticas foram utilizados testes qui-quadrado de heterogeneidade e de tendência linear. Verificou-se que 50% e 25,9% das crianças avaliadas não haviam consumido verduras de folhas e legumes nos sete dias anteriores ao da entrevista, respectivamente. A prevalência de consumo de pelo menos um dia na última semana de frituras foi cerca de 60% e de refrigerantes e sucos artificiais foi de 82%. Crianças do sexo feminino, cujas mães possuíam maior idade e escolaridade, apresentaram as maiores prevalências de consumo de alimentos marcadores de alimentação saudável. Diante desses dados, a intensificação de campanhas de educação nutricional com abordagens inovadoras pode ajudar a melhorar a alimentação das crianças.