Root canal microbiota as an augmented reservoir of antimicrobial resistance genes in type 2 diabetes mellitus patients

Abstract Antimicrobial resistance is a global public health problem. Root canal microbiota associated with apical periodontitis represents a well-known reservoir of antimicrobial resistance genes (ARGs). However, the effect of type 2 diabetes mellitus (T2DM) in this reservoir is unknown. This study aimed to establish if root canal microbiota associated with apical periodontitis in T2DM patients is an augmented reservoir by identifying the prevalence of nine common ARGs and comparing it with the prevalence in nondiabetic patients. Methodology This cross-sectional study included two groups: A T2DM group conformed of 20 patients with at least ten years of living with T2DM and a control group of 30 nondiabetic participants. Premolar or molar teeth with pulp necrosis and apical periodontitis were included. A sample was collected from each root canal before endodontic treatment. DNA was extracted, and ARGs were identified by polymerase chain reaction. Results tetW and tetM genes were the most frequent (93.3 and 91.6%, respectively), while ermA was the least frequent (8.3%) in the total population. The distribution of the ARGs was similar in both groups, but a significant difference (p<0.005) was present in ermB, ermC, cfxA, and tetQ genes, being more frequent in the T2DM group. A total of eighty percent of the T2DM patients presented a minimum of four ARGs, while 76.6% of the control group presented a maximum of three. Conclusions Root canal microbiota associated with apical periodontitis in T2DM patients carries more ARGs. Therefore, this pathological niche could be considered an augmented reservoir.

Iodine nutrition in elementary state schools of Queretaro, Mexico: correlations between urinary iodine concentration with global nutrition status and social gap index / Consumo de iodo em escolas de ensino fundamental de Querétaro, México: correlação entre a concentração urinária de iodo, o estado nutricional geral e o índice de desigualdade social

OBJECTIVE AND METHODS: To estimate median urinary iodine concentration (UIC), and to correlate it with global nutrition indicators and social gap index (SGI) in 50 elementary state schools from 10 municipalities in the State of Queretaro, Mexico. RESULTS: 1,544 students were enrolled and an above of requirements of iodine intake was found (median UIC of 297 µg/L). Iodine status was found as deficient, adequate, more than adequate and excessive in 2, 4, 19 and 25 schools, respectively. Seventy seven percent of table salt samples showed adequate iodine content (20-40 ppm), while 9.6% of the samples had low iodine content (< 15 ppm). Medians of UIC per school were positively correlated with medians of body mass index (BMI) by using the standard deviation score (SDS) (r = 0.47; p < 0.005), height SDS (r = 0.41; p < 0.05), and overweight and obesity prevalence (r = 0.41; p < 0.05). Medians of UIC per school were negatively correlated with stunting prevalence (r = -0.39; p = 005) and social gap index (r = -0.36; p < 0.05). Best multiple regression models showed that BMI SDS and height were significantly related with UIC (p < 0.05). CONCLUSIONS: There is coexistence between the two extremes of iodine intake (insufficient and excessive). To our knowledge, the observed positive correlation between UIC and overweight and obesity has not been described before, and could be explained by the availability and consumption of snack food rich in energy and iodized salt.

OBJETIVO E MÉTODOS: Estimar a concentração de iodo urinário (CIU) mediana e correlacioná-la com os indicadores de nutrição geral e com o índice de desigualdade social (IDS) de 50 escolas estaduais de ensino fundamental de 10 municípios do estado de Querétaro, no México. RESULTADOS: Utilizou-se um total de 1.544 crianças e encontrou-se uma ingestão acima das necessidades de iodo (CIU mediana de 297 µg/L). O nível de iodo determinado foi deficiente, adequado, mais do que adequado e excessivo em 2, 4, 19 e 25 escolas, respectivamente. Setenta e sete por cento de amostras de sal de mesa mostraram uma quantidade de iodo adequada (20-40 ppm), enquanto 9,6% das amostras tinham um teor de iodo baixo (< 15 ppm). As medianas de CIU por escola foram correlacionadas positivamente com as medianas do índice de massa corporal (IMC) usando o desvio-padrão da contagem (DP) (r = 0,47; p < 0.005), o DP da altura (r = 0,41; p < 0.05) e a prevalência de sobrepeso e de obesidade (r = 0,41; p < 0,05). As medianas de CUI por escola foram correlacionadas negativamente com a prevalência de desnutrição (r = -0.39; p = 005) e com o índice de desigualdade social (r = -0.36; p < 0,05). Os melhores modelos de regressão múltipla mostraram que a DP do IMC e a altura foram relacionados significativamente com a CIU (p < 0,05). CONCLUSÃO: Existe uma convivência entre os dois extremos de ingestão de iodo (insuficiente e excessiva). Em nosso conhecimento, a correlação positiva entre a CIU, o excesso de peso e a obesidade não foi descrita anteriormente e poderia ser explicada pela disponibilidade e consumo de alimentos ou refeições ricos(as) em energia e sal iodado.

Importance of iodine in pregnancy

Iodine is an essential constituent of thyroid hormones (TH). TH actively take part in critical periods of brain development during embryonic, fetal and postnatal stages. Therefore the absence of TH or iodine in these critical periods produces an irreversible brain damage. In fact, it is known that iodine deficiency is the leading cause of preventable brain damage worldwide. Because of the physiological adjustments during pregnancy iodine requirements increase significantly from 150 μg per day in non-pregnant adult women to 250 μg per day. Moreover, recent epidemiological studies around the world show that iodine intake during pregnancy is insufficient in many countries, even in developed countries like Australia, Spain and Italy. In the present work an overview of the importance of iodine nutrition during pregnancy is given.

Importancia del yodo en la gestación. El yodo es un nutrimento constituyente indispensable de las hormonas tiroideas (HT). Las HT participan activamente en periodos críticos del desarrollo cerebral durante las etapas embrionaria, fetal y posnatal. Por lo tanto la ausencia o deficiencia de las HT o de yodo en estas etapas del desarrollo produce un daño cerebral irreversible. De hecho, se sabe que la deficiencia de yodo es la principal causa de daño cerebral prevenible en el mundo. Debido a los ajustes fisiológicos propios de la gestación los requerimientos de yodo se incrementan notablemente, pasando de 150 μg al día en la mujer adulta no gestante a 250 μg al día durante el embarazo. Por otra parte, estudios epidemiológicos recientes hechos en todo el mundo muestran que el consumo de yodo durante la gestación es insuficiente en varios países; incluso en países desarrollados como Australia y España e Italia. En la presente revisión se da un panorama general de la importancia del consumo adecuado de yodo durante la gestación.

Estudio de factores nutricionales asociados a la prevención de cáncer mamario: importancia de los modelos animales / Study of nutritional factors related to breast cancer prevention: importance of animal models approaches

El cáncer mamario es la neoplasia más común en la mujer a nivel mundial y debido a que no se conoce su etiología no se ha logrado establecer una estrategia efectiva de prevención. Los principales factores de riesgo asociados al cáncer mamario se clasifican en: hereditarios, endocrino-reproductivos y factores ambientales; entre los que se incluye la dieta. Los modelos animales de inducción química de cáncer mamario con los carcinógenos 7, 12-dimetilbenzo[a]antraceno y N-metil N-nitrosourea han sido de gran utilidad para el estudio de la biología del cáncer mamario así como de su tratamiento y prevención. En esta revisión presentamos la utilidad y ventajas de dichos modelos animales en el estudio de factores nutricionales asociados al cáncer mamario para la generación de estrategias de prevención. Se revisa brevemente diferentes estrategias y abordajes experimentales así como efectos fisiológicos y mecanismo de acción de algunos de los factores nutricionales estudiados con estos modelos de carcinogénesis mamaria. Los factores nutricionales que abordamos son: a) la restrciión dietaria de energía y el exceso de grasa. b) la soya y los fitoestrógenos, c) los retinoides y cartenoides, d) el ácido linoleico conjugado, y e) las algas marinas y el yodo