Dietary exposures and allergy prevention in high-risk infants

Allergic conditions in children are a prevalent health concern in Canada. The burden of disease and the societal costs of proper diagnosis and management are considerable, making the primary prevention of allergic conditions a desirable health care objective. This position statement reviews current evidence on dietary exposures and allergy prevention in infants at high risk for developing allergic conditions. It revisits previous dietary recommendations for pregnancy, breastfeeding and formula feeding, and provides an approach for introducing solid foods to high-risk infants. While there is no evidence that delaying the introduction of any specific food beyond six months of age helps to prevent allergy, the protective effect of early introduction of potentially allergenic foods (at four to six months of age) remains under investigation. Recent research appears to suggest that regularly ingesting a new, potentially allergenic food may be as important as when that food is first introduced. © Canadian Paediatric Society 2013

Somatic diversification of variable lymphocyte receptors in the agnathan sea lamprey

Although jawless vertebrates are apparently capable of adaptive immune responses, they have not been found to possess the recombinatorial antigen receptors shared by all jawed vertebrates. Our search for the phylogenetic roots of adaptive immunity in the lamprey has instead identified a new type of variable lymphocyte receptors (VLRs) composed of highly diverse leucine-rich repeats (LRR) sandwiched between amino- and carboxy-terminal LRRs. An invariant stalk region tethers the VLRs to the cell surface by means of a glycosyl-phosphatidyl-inositol anchor. To generate rearranged VLR genes of the diversity necessary for an anticipatory immune system, the single lamprey VLR locus contains a large bank of diverse LRR cassettes, available for insertion into an incomplete germline VLR gene. Individual lymphocytes express a uniquely rearranged VLR gene in monoallelic fashion. Different evolutionary strategies were thus used to generate highly diverse lymphocyte receptors through rearrangement of LRR modules in agnathans ( jawless fish) and of immunoglobulin gene segments in gnathostomes ( jawed vertebrates).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62870/1/nature02740.pd

Ankyloglossia and breastfeeding

Ankyloglossia (\u27tongue-tie\u27) is a relatively common congenital anomaly characterized by an abnormally short lingual frenulum, which may restrict tongue tip mobility. There is considerable controversy regarding its diagnosis, clinical significance and management, and there is wide variation in practice in this regard. Most infants with ankyloglossia are asymptomatic and do not exhibit feeding problems. Based on available evidence, frenotomy cannot be recommended for all infants with ankyloglossia. There may be an association between ankyloglossia and significant breastfeeding difficulties in some infants. This subset of infants may benefit from frenotomy (the surgical division of the lingual frenulum). When an association between significant tongue-tie and major breastfeeding problems is clearly identified and surgical intervention is deemed to be necessary, frenotomy should be performed by a clinician experienced with the procedure and using appropriate analgesia. More definitive recommendations regarding the management of tongue-tie in infants await clear diagnostic criteria and appropriately designed trials