Maternal-infant attachment: a developmental perspective

Enhanced purification coupled with biophysical analyses shows cross-β structure as a core building block for Streptococcus mutans functional amyloids

Streptococcus mutans is an etiologic agent of human dental caries that forms dental plaque biofilms containing functional amyloids. Three amyloidogenic proteins, P1, WapA, and Smu_63c were previously identified. C123 and AgA are naturally occurring amyloid-forming fragments of P1 and WapA, respectively. We determined that four amyloidophilic dyes, ThT, CDy11, BD-oligo, and MK-H4, differentiate C123, AgA, and Smu_63c amyloid from monomers, but non-specific binding to bacterial cells in the absence of amyloid precludes their utility for identifying amyloid in biofilms. Congo red-induced birefringence is a more specific indicator of amyloid formation and differentiates biofilms formed by wild-type S. mutans from a triple ΔP1/WapA/Smu_63c mutant with reduced biofilm forming capabilities. Amyloid accumulation is a late event, appearing in older S. mutans biofilms after 60 hours of growth. Amyloid derived from pure preparations of all three proteins is visualized by electron microscopy as mat-like structures. Typical amyloid fibers become evident following protease digestion to eliminate non-specific aggregates and monomers. Amyloid mats, similar in appearance to those reported in S. mutans biofilm extracellular matrices, are reconstituted by co-incubation of monomers and amyloid fibers. X-ray fiber diffraction of amyloid mats and fibers from all three proteins demonstrate patterns reflective of a cross-β amyloid structure.

Impact of forced separation policy on incarcerated postpartum mothers

The number of incarcerated women in the United States is steadily increasing with 9% giving birth while serving time. Mothers and babies are routinely separated immediately and during most of the postpartum period. This qualitative study examines the impact of this policy by exploring the nature and meaning of the mother-infant bonding experience when the mothers know separation is coming. Twelve incarcerated postpartum mothers were interviewed during the early postpartum period about their antepartum and postpartum relationships with their babies. Qualitative data analysis produced four relational themes: (a) "a love connection," (b) "everything was great until I birthed," (c) "feeling empty and missing a part of me," and (d) "I don't try to think too far in advance." Results of this qualitative study provide information to professionals exploring gender-sensitive prison policies for the growing female population.