Pregnancy denial and early infant development: a case-control observational prospective study.

BACKGROUND: The denial of pregnancy is the non-recognition of the state of the current pregnancy by a pregnant woman. It lasts for a few months or for the whole pregnancy, with generally few physical transformations. In this study, we will consider the denial of pregnancy as a late declaration of pregnancy (beyond 20 weeks of gestation) as well as a lack of objective perceptions of this pregnancy. The main objective of this study is to explore the relationship between pregnancy denial and the development of the infant (attachment pattern of the infant, early interactions of mother-infant dyads, and early development of the infant). METHODS: The design is a case-control prospective study, which will compare two groups of mother-infant dyads: a "case" group with maternal denials of pregnancy and a "control" group without denials of pregnancy. A total of 140 dyads (mother + infant) will be included in this study (70 cases and 70 controls) and followed for 18 months. The setting is a national recruitment setting with 10 centers distributed all over France. The follow-up of the "cases" and the "controls" will be identical and will occur over 5 visits. It will include measures of the infant attachment pattern, the quality of early mother-infant interaction and infant development. DISCUSSION: This study aims to examine the pathogenesis of pregnancy denial as well as its consequences on early infant development and early mother-infant interaction. TRIAL REGISTRATION: Clinical Trial Number: NCT02867579 on the date of 16 August 2016 (retrospectively registered).

Biocompatibility and light transmission of liposomal lenses.

PURPOSE: To validate the biocompatibility and transmittance properties of contact lenses bearing intact liposomes. These liposomal lenses loaded with therapeutics can be used as ophthalmic drug delivery systems. METHODS: The biocompatibility of soft contact lenses, coated with liposomes was evaluated through in vitro direct and indirect cytocompatibility assays on human corneal epithelial cells, on reconstructed human corneas and on ex vivo rabbit corneas. The direct and indirect transmission spectra of liposome-covered lenses were also evaluated to test if they transmit all wavelengths of the ultraviolet-visible spectrum, to thereby fulfill their optical function, without gross alteration of the colors perception and with a minimum of light dispersion. RESULTS: Contact lenses bearing layers of stable liposomes did not induce any significant changes in cell viability and in cell growth, compared with lenses bearing no liposome. Elution assays revealed that no cytotoxic compound leaks from the lenses whether bearing liposomes or not. Histological analyses of reconstructed human corneas and ex vivo rabbit corneas directly exposed to liposomal lenses revealed neither alteration to the cell nor to the tissue structures. Contact lenses bearing layers of liposomes did not significantly affect light transmission compared with control lenses without liposome at the wavelength of maximal photopic sensitivity, i.e., 550 nm. In addition, the contact lenses afford more eye protection in the ultraviolet spectrum, compared with the control lenses. CONCLUSIONS: Liposomal contact lenses are biocompatible and their transmittance properties are not affected in the visible light range.

Antibacterial activity of contact lenses bearing surface-immobilized layers of intact liposomes loaded with levofloxacin.

In vitro methods to evaluate antibacterial activity were used with contact lenses bearing levofloxacin-loaded liposomes developed for the prevention and treatment of bacterial ocular infections such as keratitis. Levofloxacin was incorporated into liposomes before these intact liposomes were immobilized onto the surfaces of soft contact lenses using a multilayer immobilization strategy. The release of levofloxacin from contact lenses bearing 2, 5, and 10 layers of liposomes into a saline buffer at 37 degrees C was monitored by fluorescence. The levofloxacin release, as a function of time, was described by a mechanism taking into account two independent first-order kinetic models. The total release of levofloxacin from the contact lenses was completed within 6 days. The release of levofloxacin from contact lenses bearing 10 layers of liposomes and subsequently soaked overnight in a levofloxacin solution was also studied and compare to that of dried contact lenses without any chemical modification rehydrated in a levofloxacin solution. The antibacterial activity of the liposome-coated contact lenses against Staphylococcus aureus was evaluated by measuring (i) the diameters of the inhibition zone on an agar plate and (ii) the optical density using a broth assay. The liposome-coated lenses showed an antibacterial activity both on agar and in broth following 24 h. When initial bacteria inocula were equal or below 10(6) CFU/mL, all the bacteria were inhibited within 2 h. When using initial bacteria inocula of 10(8) CFU/mL, an initial burst release provided by soaking the liposomal lenses was required for the first hours to inhibit bacteria growth.

Fabrication and characterization of contact lenses bearing surface-immobilized layers of intact liposomes.

Intact liposomes were immobilized onto soft contact lenses. In the first step, polyethylenimine was covalently bounded onto the hydroxyl groups available on the surface of a commercial contact lens (Hioxifilcon B). Then, NHS-PEG-biotin molecules were bounded onto the surface amine groups by carbodiimide chemistry. NeutrAvidin were bounded onto the PEG-biotin layer. Liposomes containing PEG-biotinylated lipids were docked onto the surface-immobilized NeutrAvidin. Consecutive addition of further NeutrAvidin and liposome layers enabled fabrication of multilayers. Multilayers of liposomes were also produced by exposing contact lenses coated with NeutrAvidin to liposome aggregates produced by the addition of free biotin in solution. XPS revealed the immobilization of the different layers. By blocking with excess biotin surface-immobilized NeutrAvidin on contact lenses bearing PEG-biotin layers produced under cloud point conditions, ELISA showed that the docking of NeutrAvidin was dependent on biotin-NeutrAvidin affinity binding, with little evidence for nonspecific physisorption; however, it was not possible to differentiate specific versus nonspecific binding of NeutrAvidin attached onto PEG-biotin layers grafted without cloud point conditions. AFM imaging revealed liposome sizes of 106 and 155 nm for layers of liposomes produced (i) by the consecutive addition of further NeutrAvidin and liposomes and (ii) by the exposure of NeutrAvidin-coated contact lenses to liposome aggregates, respectively. The release kinetics of a fluorescent dye demonstrated that intact liposomes had been immobilized onto contact lens surfaces. The stability of surface-immobilized liposomes onto contact lens surfaces showed temperature dependence. Surface-bound liposomes can be stored up to 1 month at 4 degrees C with little release of their content.