Oestradiol levels may differ between premenopausal women, ages 18-50, with type 1 diabetes and matched controls.

BACKGROUND: This study aimed to investigate whether oestradiol differs between premenopausal women with and without type 1 diabetes and whether levels are associated with such factors as age, reproductive history or diabetes management. METHODS: Oestradiol in premenopausal women with type 1 diabetes (n = 89; age = 18-50 years; duration = 13-18 years) and age-matched/race-matched controls without diabetes (n = 76) was collected during a cross-sectional ancillary study of the Wisconsin Diabetes Registry Study, a population-based incident cohort. Total and bioavailable oestradiol and sex hormone-binding globulin were compared using multivariable regression (e.g. adjusting for reproductive history). RESULTS: Adjusted mean total and bioavailable oestradiol did not differ overall by diabetes status (p ≥ 0.74), while adjusted mean sex hormone-binding globulin was higher in type 1 diabetes women (p = 0.02). However, only in women with type 1 diabetes and not controls (interaction p = 0.0005) was total oestradiol positively associated with the duration of reproductive years with unsuppressed ovarian function (UnsuppOvFx = years since menarche minus years on hormonal contraceptives/pregnant/breastfeeding). When stratified into less than/equal to or greater than the median 9 years' duration of UnsuppOvFx, compared with controls, women with type 1 diabetes had significantly lower total oestradiol in the ≤9 years group [ß = -43.2 pg mL-1 (-158.6 pmol L-1 ), p = 0.04] and significantly higher total oestradiol in the >9 years group [ß = 53.9 pg mL-1 (197.9 pmol L-1 ), p = 0.04]. Results remained consistent during additional statistical adjustments and sensitivity analyses. CONCLUSIONS: Compared with controls, women with type 1 diabetes may have lower oestradiol when they have a shorter duration of UnsuppOvFx and higher oestradiol when they have a longer duration of UnsuppOvFx. Given the potential effects of insulin on ovarian function, oestradiol production may vary across the lifespan for women with type 1 diabetes. Copyright © 2016 John Wiley & Sons, Ltd.

Assessing Collagen and Micro-permeability at the Proanthocyanidin-treated Resin-Dentin Interface.

PURPOSE: To establish a fluorescence-based method to simultaneously assess micro-permeability and collagen cross-linking induced by chemical agents at the resin-dentin interface. MATERIALS AND METHODS: Three chemical agents were investigated (proanthocyanidin-rich grape seed extract: GSE; carbodiimide hydrochloride/N-hydroxysuccinimide: EDC/NHS; glutaraldehyde: GD) along with a control (distilled water) as primers applied on flat occlusal dentin surfaces of 48 teeth and restored with two commercially available etch-and-rinse adhesives. Resin-dentin interfaces were polished and infiltrated with rhodamine-B solution for confocal laser scanning microscopy analysis. Parameters were chosen that would allow acquisition of a simultaneous appearance of collagen and interfacial micro-permeability (rhodamine-B). Fluorescence emission intensity (FEI) was converted into numerals and values were calculated for each group. Data were statistically analyzed using one-way ANOVA and post-hoc Scheffe's and multiple comparisons tests (α = 0.05). T-tests with Pearson correlations were used to investigate correlations between collagen cross-linking and micro-permeability. RESULTS: The FEI of collagen was the highest for GD, followed by GSE, with no significant differences between EDC/ NHS and the control group (p > 0.05). Micro-permeability was significantly affected by the adhesives (p < 0.05). Micro- permeability was the lowest for GSE groups, regardless of the adhesives (p < 0.001). Weak correlations were found between micro-permeability and collagen auto-fluorescence. CONCLUSIONS: Non-enzymatic collagen cross-linking induced by GSE and GD can be detected by increased collagen auto-fluorescence, and results in reduced interfacial micro-permeability. Increased collagen auto-fluorescence was correlated with fluorescent collagen cross-links and decreased micro-permeability at the resin-dentin interface. Collagen auto-fluorescence is a useful tool to detect auto-fluorescent exogenous cross links and their potential impact on the quality of the resin-dentin interface.

Potential role of surface wettability on the long-term stability of dentin bonds after surface biomodification.

Degradation of the adhesive interface contributes to the failure of resin composite restorations. The hydrophilicity of the dentin matrix during and after bonding procedures may result in an adhesive interface that is more prone to degradation over time. This study assessed the effect of chemical modification of the dentin matrix on the wettability and the long-term reduced modulus of elasticity (Er) of adhesive interfaces. Human molars were divided into groups according to the priming solutions: distilled water (control), 6.5% Proanthocyanidin-rich grape seed extract (PACs), 5.75% 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride/1.4% n-hydroxysuccinimide (EDC/NHS) and 5% Glutaraldehyde (GA). The water-surface contact angle was assessed before and after chemical modification of the dentin matrix. The demineralized dentin surface was treated with the priming solutions and restored with One Step Plus (OS) and Single Bond Plus (SB) and resin composite. Er of the adhesive, hybrid layer and underlying dentin was evaluated after 24h and 30 months in artificial saliva. The dentin hydrophilicity significantly decreased after application of the priming solutions. Aging significantly decreased Er in the hybrid layer and underlying dentin of control groups. Er of GA groups remained stable over time at the hybrid layer and underlying dentin. Significant higher Er was observed for PACs and EDC/NHS groups at the hybrid layer after 24h. The decreased hydrophilicity of the modified dentin matrix likely influence the immediate mechanical properties of the hybrid layer. Dentin biomodification prevented substantial aging at the hybrid layer and underlying dentin after 30 months storage.