Basal Lamina Changes During Tissue Interactions in Hair Follicles—An In Vitro Study of Normal Dermal Papillae and Vitamin A-Induced Glandular Morphogenesis

Skin pieces from 14-day fetal mice were cultivated for 1-10 days prior to fixation and sectioning. Subsequently, sections were studied by light and transmission electron microscopy. In a standard medium the lateral hair follicle walls showed progressive maturation of the basal lamina, while the hair matrix, at the time of a known tissue interaction, showed the formation of gaps in the basal lamina, With heterotypic cell contacts through the gaps. In a vitamin-A enriched medium similar changes occurred, not only at the hair matrix, but also at lateral follicle walls, at the sites of, and prior to, budding and glandular morphogenesis. This study shows that the induction of hair matrix by dermal papilla may perhaps be added to the list of normal tissue interactions in which heterotypic cell contacts occur. It also suggests that vitamin-A induced glandular morphogenesis might come about through a mechanism resembling a normal tissue interaction

Distinct fibroblast lineages determine dermal architecture in skin development and repair

This work was funded by the Wellcome Trust (F.M.W., A.C.F.-S.), the Medical Research Council (MRC) (F.M.W., A.C.F.-S.) and the European Union FP7 programme: TUMIC (F.M.W.), HEALING (F.M.W.) and EpigeneSys (A.C.F.-S.). B.M.L. is the recipient of a FEBS long-term fellowship. K.K. is the recipient of a MRC PhD Studentship. The authors acknowledge financial support from the Department of Health via theNational Institute forHealth Research (NIHR) comprehensive Biomedical Research Centre award to Guy’s & St Thomas’ NHS Foundation Trust in partnership with King’s College London (KCL) and King’s College Hospital NHS Foundation Trust. Input from M. Mastrogiannaki, A. Reimer and B. Trappmann is gratefully acknowledged

A spatial relationship between innervation and the early differentiation of vibrissa follicles in the embryonic mouse.

The present study has demonstrated that the mystacial vibrissae of the mouse began to develop at about 12 days of gestation on two plates of thickened ectoderm called the 'whisker pads' which were located on either side of the snout above the margin of the upper lip. Each whisker pad was traversed by five rostrocaudal skin ridges. The individual vibrissae developed along the ridges in a caudorostral sequence. Four new sub-stages of vibrissa follicle development which occurred prior to Stage 1 of Davidson & Hardy (1952) were described. The first of these, Stage A, was the formation of a small nerve plexus under the skin ridge. Stage B was then characterized by the formation of a dermal condensation above the nerve plexus. The epithelium over the dermal condensation began to thicken at Stage C and grow down into the dermal condensation at Stage D. The early morphogenesis of the mystacial vibrissa follicles of the mouse was compared to that of teeth and mammary glands. The possibility of nerve involvement in determining the pattern of follicle array on the snout was discussed. The sequence of the morphological changes in the dermal and epidermal components of the early follicles was related to the present knowledge of epithelial-mesenchymal interactions which occur during this phase of follicle development

The integration of barcode scanning technology into Canadian public health immunization settings

AbstractBackgroundAs part of a series of feasibility studies following the development of Canadian vaccine barcode standards, we compared barcode scanning with manual methods for entering vaccine data into electronic client immunization records in public health settings.MethodsTwo software vendors incorporated barcode scanning functionality into their systems so that Algoma Public Health (APH) in Ontario and four First Nations (FN) communities in Alberta could participate in our study. We compared the recording of client immunization data (vaccine name, lot number, expiry date) using barcode scanning of vaccine vials vs. pre-existing methods of entering vaccine information into the systems. We employed time and motion methodology to evaluate time required for data recording, record audits to assess data quality, and qualitative analysis of immunization staff interviews to gauge user perceptions.ResultsWe conducted both studies between July and November 2012, with 628 (282 barcoded) vials processed for the APH study, and 749 (408 barcoded) vials for the study in FN communities. Barcode scanning led to significantly fewer immunization record errors than using drop-down menus (APH study: 0% vs. 1.7%; p=0.04) or typing in vaccine data (FN study: 0% vs. 5.6%; p<0.001). There was no significant difference in time to enter vaccine data between scanning and using drop-down menus (27.6s vs. 26.3s; p=0.39), but scanning was significantly faster than typing data into the record (30.3s vs. 41.3s; p<0.001). Seventeen immunization nurses were interviewed; all noted improved record accuracy with scanning, but the majority felt that a more sensitive scanner was needed to reduce the occasional failures to read the 2D barcodes on some vaccines.ConclusionEntering vaccine data into immunization records through barcode scanning led to improved data quality, and was generally well received. Further work is needed to improve barcode readability, particularly for unit-dose vials