Longitudinal Ultrasound Evaluation of Dilapan-S During Cervical Ripening.

OBJECTIVE: To assess the diameter change of hygroscopic rod dilation during 12 hours of cervical ripening. METHODS: This was an observational, prospective study of term women undergoing labor induction with a bishop score ≤ 6. Women were allocated into two groups (soaked gauze or no gauze) stratified by parity. Using transvaginal ultrasound, maximal rod diameters were obtained in a longitudinal plane. Measurements were taken at four pre-specified time points (3, 6, 8, and 12 hours). All rods were removed at 12 hours from insertion. Patient satisfaction scores between the groups were assessed. To evaluate if measures were significantly different among the four time points, a generalized linear model was used. Independent t-tests were used to compare mean rod diameter values and pain measures between the two groups. Fisher Exact tests were used to evaluate categorical satisfaction measures. RESULTS: Forty-four women were recruited with a total of 178 hygroscopic rods placed. Mean rod diameters (mm) were significantly different among the four time periods (3 hour: 7.9 mm [SD 0.9]; 6 hour: 9.4 mm [SD 0.9]; 8 hour: 10.0 mm [SD 0.9]; 12 hour: 10.9 mm [SD 0.8]; P-value <.001). After stratifying by the use of gauze, there was no difference in rod diameters at 3, 6, 8, and 12 hours respectively. There was no difference in patient satisfaction scores between the two groups. CONCLUSION: The majority of hygroscopic rod dilation occurs within the first 8 hours of cervical ripening. Placement of saturated gauze does not accelerate rod dilation.

Binding between an amine cationic surfactant and DNA and surface properties of the resultant aggregates.

Binding between cetyltrimethylammonium bromide, a cationic surfactant, and a variety of lengths of single stranded DNA was measured using fluorescence polarization and a simple cooperative model was used to obtain dissociation constants on the order of 1 × 10-5 for the aggregates that formed. Aggregation depended on strand length where strands much shorter than 40 nucleotides (for example strands of 24-nucleotides) were too short to form the same size aggregates. Other factors such as salt concentration and temperature also affected aggregate formation: increasing either the salt concentration or performing binding at the highest temperature studied (60 °C) made it more difficult for aggregates to form. Both heating and dilution of aggregates caused the anisotropy signal to decrease, which suggested that the complexes fell apart under these conditions. Force spectroscopy of aggregate surfaces showed that both electrostatic and hydrophobic adhesive forces were present between aggregates and derivatized AFM tips. These findings can be used to better understand the stability of cationic surfactant-DNA aggregates and may provide guidance for lipid nanoparticle design used in vaccine development and therapeutics.

Functional lacrimal gland regeneration by transplantation of a bioengineered organ germ.

The lacrimal gland has a multifaceted role in maintaining a homeostatic microenvironment for a healthy ocular surface via tear secretion. Dry-eye disease, which is caused by lacrimal gland dysfunction, is one of the most prevalent eye diseases that cause corneal epithelial damage and results in significant loss of vision and a reduction in the quality of life. Here we demonstrate orthotopic transplantation of bioengineered lacrimal gland germs into adult mice with an extra-orbital lacrimal gland defect, a mouse model that mimics the corneal epithelial damage caused by lacrimal gland dysfunction. The bioengineered lacrimal gland germs and harderian gland germs both develop in vivo and achieve sufficient physiological functionality, including tear production in response to nervous stimulation and ocular surface protection. This study demonstrates the potential for bioengineered organ replacement to functionally restore the lacrimal gland.

Porous silk fibroin film as a transparent carrier for cultivated corneal epithelial sheets.

Biological carriers, such as the amniotic membrane and serum-derived fibrin, are currently used to deliver cultivated corneal epithelial sheets to the ocular surface. Such carriers require being transparent and allowing the diffusion of metabolites in order to maintain a healthy ocular surface. However, safety issues concerning biological agents encouraged the development of safer, biocompatible materials as cell carriers. We examined the application of porous silk fibroin films with high molecular permeability prepared by mixing silk fibroin and poly(ethylene glycol) (PEG), and then removal of PEG from the silk-PEG films. Molecular permeability of porous silk fibroin film is higher than untreated silk fibroin film. Epithelial cells were isolated from rabbit limbal epithelium, and seeded onto silk fibroin coated wells and co-cultured with mitomycin C-treated 3T3 fibroblasts. Stratified epithelial sheets successfully engineered on porous silk fibroin film expressed the cornea-specific cytokeratins K3 and K12, as well as the corneal epithelial marker pax6. Basement membrane components such as type-IV collagen and integrin ß1 were expressed in the stratified epithelial sheets. Further more, colony-forming efficiency of dissociated cells was similar to primary corneal epithelial cells showing that progenitor cells were preserved. The biocompatibility of fibroin films was confirmed in rabbit corneas for up to 6 months. Porous silk fibroin film is a highly transparent, biocompatible material that may be useful as a carrier of cultivated epithelial sheets in the regeneration of corneal epithelium.