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Maternal infections, nutrient deficiencies, and inflammation (MINDI) co-exist in lactating indigenous women in Panama, but their impact on maternal iron status and infant growth is unknown. For this secondary analysis of cross-sectional data of lactating mothers from our MINDI cohort, we investigated associations of MINDI variables with maternal anemia, elevated serum transferrin receptor (sTfR), low serum iron, hepcidin, ferritin, and infant weight-for-age (WAZ), length-for-age (LAZ), and head-circumference-for-age (HCAZ) Z-scores in 99 mother-infant dyads. A bootstrapping resampling procedure preselected covariates for inclusion in multivariable regressions models from chronic maternal infections and nutritional status [folate, vitamins A, D, retinol-binding protein (RBP), insulin-growth factor-1 (IGF-1)] and inflammation [C-reactive protein (CRP), cytokines, platelet indices] indicators. Anemia was prevalent (53.5%) but underestimated due to widespread low plasma volume (

Recently the Canadian government, announced its new ‘feminist international assistance policy’ towards achieving the United Nations Sustainable Development Goals (SDGs). The core action of that pol...

Enhancement of epithelial cell attachment to laminin-5-coated titanium alloy (Ti-6Al-4V) implant material was evaluated in vitro. Protein analysis showed that Ti-6Al-4V has a high affinity for laminin-5 and adsorbed significantly more laminin-5 than laminin-1. DNA analysis showed that laminin-5 enhanced attachment of normal human epidermal keratinocytes (NHEK) to Ti-6Al-4V significantly more than did laminin-1 or uncoated controls. The effect of passivation on laminin-5 adsorption and activity on Ti-6Al-4V also was evaluated. Passivation had no significant effect on the amount of protein adsorbed; however, AFM, ESCA, and ToF-SIMS analyses suggested that passivation affects the conformation of adsorbed laminin-5. Although laminin-5 coating significantly enhanced rapid attachment of epithelial cells to both passivated and unpassivated Ti-6Al-4V, surface area measurements showed that cells spread on laminin-5-coated passivated Ti-6Al-4V covered a significantly larger surface area than cells spread on laminin-5-coated unpassivated samples. TEM analysis showed that cells formed significantly more hemidesmosomes on the surface of laminin-5 coated passivated than on the surface of laminin-5 coated unpassivated titanium alloy. The enhancement of rapid cell attachment, spreading, and hemidesmosome assembly on laminin-5-coated passivated samples may reflect better integration between epithelial cells and titanium alloy and thus may be predictive of long-term implant stability.

Diversity is what gives our society depth and arguably beauty but it also problematizes already complexsocial issues like the importance and value placed on the education. In part, this challenge existsbecause public education is founded on the "values and belief systems of the dominant cultural andlinguistic class" (Goddard & Hart, 2007, p. 16) yet schools are a complex, heterogeneous weave ofcultures (Murakami-Ramalho, 2008). According to Chambers (2003), Canadian students are "probablythe most ethnically, racially, linguistically, and religiously diverse of any school population in the world"(p. 223). This is no less true in the United States where one third of the school population is consideredethnically, linguistically or culturally diverse (Ladson-Billings, 2005). In European countries, the growth ofthe population has also shifted towards greater diversity; Switzerland, for example is now 20% foreignborn (Levin, 2008). Despite this reality, schools leaders struggle to find ways to address the needs ofculturally diverse students and their families (Bazron, Osher & Fleischman, 2005; Goddard & Hart,2007); this challenge creates conflict in schools, particularly for those charged with their leadership.

Publisher Summary This chapter discusses the aspects of structure and function of β4, β1, and αV integrins that are relevant to epithelial cells. Integrin α6β4 acts as a link between basement membrane and the intermediate filament cytoskeleton in epithelial cells. A proper identification of the α6β4 ligand will be an important step that may clarify many aspects of the molecular interactions between epithelial cells and basement membranes. Several laboratories concurrently produced evidence that α6β4 in epithelial cells is physically associated with structures termed hemidesmosomes. It has been speculated that α6β4 has a role in catalyzing the reorganization of hemidesmosomal components, perhaps after the recognition of a ligand in the basement membrane. Although α6β4 is diffusely distributed throughout the cytoplasm of migrating epithelial cells, as soon as migration halts, it becomes quickly polarized to the basal surface in areas of contact with the basement membrane. In addition, there is a consistent distribution of expression in carcinomas from a variety of sources. Interestingly, α6β4 appears to be expressed in carcinoma cells whether or not the normal tissue of origin is α6β4 positive.

Within the integrin family, there are two groups of receptors that bind laminin. One of these groups comprises the heterodimers alpha 3 beta 1, alpha 6 beta 1, and alpha 7 beta 1, all of which bind the E8 fragment of laminin, and whose alpha subunits show significant homology at the amino acid sequence level. alpha 3 and alpha 6 exist as isoforms with distinct cytoplasmic domains (termed A and B), suggesting that they may couple laminin adhesion to distinct cellular responses. We report the identification of a new alpha 7 mRNA which encodes an alpha 7 protein isoform with an alternative cytoplasmic domain. Based on homology with alpha 3 and alpha 6 isoforms, this new isoform is classified as alpha 7A and the previously published one as alpha 7B. This result extends the similarity between alpha 3, alpha 6, and alpha 7 laminin receptor subunits and suggests a common ancestral gene. The alpha 7 beta 1 laminin receptor was proposed to be involved in myogenic differentiation. However, alpha 7 isoforms were not investigated in that context. We detected the alpha 7B isoform mRNA in all tissues and cell types tested, including myocardial and skeletal muscle. In contrast, the alpha 7A isoform was detectable exclusively in skeletal muscle, not in myocardial muscle or cells or any other tissues or cell lines tested. Furthermore, the differentiating skeletal muscle cell line C2C12 expressed only alpha 7B at the replicating myoblast stage and acquired alpha 7A expression upon induction of differentiation and fusion. Splicing of alpha 7B mRNA in C2C12 occurred shortly after myogenin expression and could be an indicator of progression through the program of skeletal muscle differentiation.

The integrin family of adhesion receptors consists of several heterodimeric glycoproteins, each composed of one alpha and one beta subunit. Three different mammalian beta subunits, beta 1, beta 2, and beta 3, have been sequenced, but recent evidence suggests the existence of several others. Amplification of guinea pig airway epithelial cell cDNA with oligonucleotide primers designed to recognize consensus integrin beta subunit sequences led to the identification of a novel partial cDNA sequence. Clones containing portions of this sequence were used to screen cDNA libraries constructed from the human pancreatic carcinoma cell line FG-2 and identified a series of overlapping clones encoding the full-length sequence of the human homologue of this protein. This sequence of 788 amino acids is 43, 38, and 47% identical to the sequences of beta 1, beta 2, and beta 3, respectively. Features shared between this novel protein and the previously sequenced beta subunits include the positions of all 56 cysteine residues in the extracellular domain, the single putative transmembrane domain, and the short putative cytoplasmic domain. However, a unique 11-amino acid extension at the carboxyl terminus, not present in any of the other beta subunits, is suggestive of distinctive interactions with cytoplasmic components. Comparison of the human and guinea pig sequences reveals a high degree (94%) of cross-species conservation. Because this protein is clearly distinct from the two other recently described integrins beta 4 and beta 5, we propose to designate it beta 6.