Impact of early-life feeding on local intestinal microbiota and digestive system development in piglets.

Early-life gut microbial colonisation is known to influence host physiology and development, shaping its phenotype. The developing gastro-intestinal tract of neonatal piglets provides a "window of opportunity" for programming their intestinal microbiota composition and corresponding intestinal development. Here, we investigated the impact of early feeding on jejunum and colon microbiota composition, and intestinal maturation in suckling piglets. From two days of age, early-fed (EF; n = 6 litters) piglets had access to solid feed containing a mixture of fibres till weaning (day29) in addition to sow's milk, whereas the control (CON; n = 6 litters) piglets exclusively fed on sow's milk. Early feeding elicited a significant impact on the colon microbiota, whereas no such effect was seen in the jejunal and ileal microbiota. Quantified eating behavioural scores could significantly explain the variation in microbiota composition of EF piglets and support their classification into good, moderate, and bad eaters. Members of the Lachnospiraceae family, and the genera Eubacterium, Prevotella, and Ruminococcus were quantitatively associated with eating scores. EF piglets were found to have a decreased pH in caecum and colon, which coincided with increased short-chain fatty acid (SCFA) concentrations. Moreover, they also had increased weights and lengths of several intestinal tract segments, as well as a decreased villus-crypt ratio in jejunal mucosa and an increased abundance of proliferative cells in colon mucosa. The approaches in this study indicate that early feeding of a mixed-fibre (pre-weaning) diet changes the microbiota composition, pH, and fermentation products in the distal gut of piglets, while it also alters both macroscopic and microscopic intestinal measurements. These results exemplify the potential of early feeding to modulate intestinal development in young piglets.

Graphene Oxide as Scaffolds for Stem Cells: An Overview.

Graphene and graphene oxide topography have an effect on the fate of stem cells such as adhesion, differentiation, and proliferation. This overview clearly shows that a new design and manipulation of associated graphene oxide stem cell culture platforms are of paramount importance as a focus in stem cell to tissue engineering applications. This overview also proposes that a film of graphene oxide is an efficient platform to modulate structure and function of multipotent mesenchymal stem/stromal cells (MSCs) and in special human adipose tissue derived mesenchymal stromal/stem cells (AT-MSCs). The implication of graphene oxide on osteogenesis, neurogenesis, oligodendrogenesis, adipogenic and epithelial differentiation is also discussed. Graphene oxide toxicity on stem cells and the importance of GO application on ATMSCs differentiation and proliferation are final topics that are being discussed.

Selective reflection spectroscopy of a resonant vapor at the interface with a metallic layer.

We discuss the properties of selective reflection spectroscopy at the interface between a resonant vapor and a complex dense medium, such as a metallic film layered on a dielectric substrate. We show that in the approximation of a low-density vapor, the signal mixes up the absorptive and dispersive components of the "effective resonant susceptibility" of the vapor, with the mixture amount governed by simple laws of linear optics. Preliminary experiments performed at the interface between Cs vapor (D2, 852-nm line) and a silver-coated glass window are reported, that show qualitatively the effect of the atom-surface van der Waals interaction.

[Immunoglobulins in the chronic phase of Chagas disease]. / Imunoglobulinas na fase crônica da doença de Chagas.

Since divergent results were obtained by different authors about immunoglobulins concentration in sera from acute and chronic cases of Chagas disease, the problem was submitted to statistical approach in field conditions in the endemic zone of Bambui, state of Minas Gerais, Brazil. Positives cases were considered in all individuals presenting evidences in parasitological, immunological or electrocardiographical examination living exactly in the same conditions, but without any evidence of infection under the same criteria. The sample consisted of 32 chronic cases and no significant difference in the immunoglobulins levels were detected in chronic cases of Chagas disease as compared with the control group. Heterophili antibodies are being determined in chronic cases and apparently there is no relationship between its concentration and pathogenic effects.