Child food insecurity is measured using parental reports of children's experiences based on an adult-generated conceptualization. Research on other child experiences (e.g. pain, exposure to domestic violence) cautions that children generally best report their own experiences, and parents' reports of children's experiences may lack adequate validity and impede effective intervention. Because this may be true of child food insecurity, we conducted semistructured interviews with mothers, children (age 9-16 y), and other household adults in 26 South Carolina families at risk for food insecurity. Interview transcripts were analyzed using a constant comparative process combining a priori with inductive coding. Child interviews revealed experiences of food insecurity distinct from parent experiences and from parent reports of children's experiences. Children experienced cognitive, emotional, and physical awareness of food insecurity. Children took responsibility for managing food resources through participation in parental strategies, initiation of their own strategies, and generation of resources to provide food for the family. Adults were not always aware of children's experiences. Where adult experiences of food insecurity are conditioned on inadequate money for food, child experiences were grounded in the immediate household social and food environment: quality of child/parent interactions, parent affect and behavior, and types and quantities of foods made available for children to eat. The new, child-derived understanding of what children experience that results from this study provides a critical basis from which to build effective approaches to identify, assess, and respond to children suffering from food insecurity.

Previous studies have indicated that retinoic acid (RA) promotes rod photoreceptor differentiation in dissociated cultures of rat retina and in zebrafish embryos. To determine whether RA will have the same affect in the mammalian retina in vivo, pregnant rats were given single i.p. injections of RA on the 18th and 20th days of gestation, and the retinas of the pups were analyzed for rods. HPLC showed that i.p. injections of RA substantially increased levels of retinal RA in the embryos. Embryonic exposure to RA caused an increase in the number of cells that differentiated as rod photoreceptors. There was a comparable decrease in the number of cells that differentiated as amacrine cells. These results demonstrate that RA promotes the differentiation of rods in vivo and further support the hypothesis that differentiation of rods is normally controlled partly by the RA concentration in the developing retina or RPE.

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SummaryThe anti-idiotypic (anti-Id) antibody (Ab) 9G4 binds a cross-reactive idiotope (CRI) present in a select group of human autoantibodies. This Id has been localized to the portion of immunoglobulin (Ig) heavy (H) chains encoded by the V,4-21 gene segment, a member of the human V.4 family. This gene segment is utilized by essentially all cold agglutinin (CA) Abs with I/i specificity isolated from patients with CA disease stemming from chronic lymphoproliferative disorders. In this study, mutational analysis of a CA has been used to determine the structural basis for 9G4 binding to Abs utilizing the VH4--21 gene segment. Recombinant CA H chain mutants were produced and their 9G4 reactivity determined. Mutants were generated by exchanging V.4-21 sequences in the FK1, CDR1, and CDK2 with corresponding sequences from a closely related gene segment V71-2, a V.4 family member that is associated neither with Abs having CA activity nor with Abs that react with 9G4. The results indicate that the motif AVY at amino acid positions 23-25 in FR1 defines the 9G4 idiotope. Reaction of these recombinant Abs with a polyclonal rabbit anti-CA antiserum absorbed to render it specific for a CA CRI also maps predominantly to FR1. These findings indicate that the solvent-exposed FR1 plays an important role in eliciting an immune response to Igs.

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