Meconium microbiome analysis identifies bacteria correlated with premature birth.

Preterm birth is the second leading cause of death in children under the age of five years worldwide, but the etiology of many cases remains enigmatic. The dogma that the fetus resides in a sterile environment is being challenged by recent findings and the question has arisen whether microbes that colonize the fetus may be related to preterm birth. It has been posited that meconium reflects the in-utero microbial environment. In this study, correlations between fetal intestinal bacteria from meconium and gestational age were examined in order to suggest underlying mechanisms that may contribute to preterm birth.Meconium from 52 infants ranging in gestational age from 23 to 41 weeks was collected, the DNA extracted, and 16S rRNA analysis performed. Resulting taxa of microbes were correlated to clinical variables and also compared to previous studies of amniotic fluid and other human microbiome niches.Increased detection of bacterial 16S rRNA in meconium of infants of <33 weeks gestational age was observed. Approximately 61·1% of reads sequenced were classified to genera that have been reported in amniotic fluid. Gestational age had the largest influence on microbial community structure (R = 0·161; p = 0·029), while mode of delivery (C-section versus vaginal delivery) had an effect as well (R = 0·100; p = 0·044). Enterobacter, Enterococcus, Lactobacillus, Photorhabdus, and Tannerella, were negatively correlated with gestational age and have been reported to incite inflammatory responses, suggesting a causative role in premature birth.This provides the first evidence to support the hypothesis that the fetal intestinal microbiome derived from swallowed amniotic fluid may be involved in the inflammatory response that leads to premature birth

Inflammatory marker S100A12 was correlated with gestational age.

<p>(A) Non-metric multidimensional scaling ordination plot depicting the relatedness of the bacterial communities from all meconium samples; communities from >33 week infants (blue) clustered more closely than those from <33 week infants (red). Analysis of similarity (ANOSIM) revealed that gestational age (<33 and >33 weeks) had the largest effect on meconium microbial structure (R = 0·16; p-value = 0·03). (B) Of the four predominant phyla, the relative abundance of Firmicutes and Actinobacteria was correlated with low gestational age (**p<0·01 & *p<0·05, respectively). (C) Genera negatively correlated with gestational age (**p<0·01) are presented. (D) Genera associated with mode of delivery (*p<0·05) were observed, though these differences are not as pronounced as the genera associated with gestational age.</p

Meconium microbiome is most suggestive of amniotic fluid origin.

<p>(A) The average percent relative abundance in meconium samples of this study for genera reported in amniotic fluid, and the oral and vaginal cavities of pregnant women^6,7,27 are displayed by the Venn diagram which distinguishes unique and shared maternal environments of genera. (B) The potential total mean contribution and standard deviation of any particular maternal locale (amniotic fluid^5,6, oral²¹, or vaginal²¹), and the phyletic distribution of contributing genera is shown in the stacked bar plot. The color assignment is as follows: Actinobacteria  =  purple; Bacteroidetes  =  green; Firmicutes  =  blue; Fusobacteria  =  orange; Proteobacteria  =  red; Tenericutes  =  aquamarine.</p

Globalización El cambio del derecho del trabajo. De un derecho de frontera a un derecho de fronteras

La presente obra contiene una reunión virtual de amigos y disípulos de quienes en dos continentes han gestado la estructura dogmática del Derecho del Trabajo. Las fronteras de la rama del derecho que toma por nombre y se ocupa del trabajo son cada vez más difusas, los esquemas de producción económica demandan cambios que el ordenamiento concede manteniendo las bases mínimas que garanticen las categorías del trabajo decente. El análisis de los esquemas laborales en el post-fordismo constituye la columna vertebral de ésta obra que contiene investigaciones de destacados juristas iberoamericanos que rinden tributo a quienes construyeron las categorías jurídicas que estructuraron el Derecho del trabajo en Italia e Iberoamérica