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BACKGROUND: Nipple reconstruction is widely regarded as the final step in post-mastectomy breast reconstruction. While grafts, local flaps, or combination approaches have been employed in nipple reconstruction, none has been able to achieve reliable long-term projection preservation. In response, we have sought to bioengineer neo-nipples in situ via the implantation of processed, decellularized cartilage xenografts placed within 3D-printed polylactic acid (PLA) scaffolds. MATERIALS AND METHODS: External nipple scaffolds were designed in-house and 3D-printed with PLA filament. Decellularized ovine xenograft infill was prepared and processed by mincing or zesting. All nipple scaffolds were placed subcutaneously on the dorsa of Sprague-Dawley rats and explanted after 1, 3, and 6 months for analysis. RESULTS: Explanted nipple scaffolds demonstrated gross maintenance of scaffold shape, diameter, and projection with accompanying increases in tissue volume. Histologic analyses revealed preservation of native cartilage architecture after 6 months without evidence of degradation. Analysis of formed tissue within the scaffolds revealed a progressive invasion of fibrovascular tissue with identifiable vascular channels and adipose tissue after 6 months in vivo. Confined compression testing revealed equilibrium moduli of both minced and zested samples that were within the expected range of previously reported human nipple tissue, while these data revealed no differences in the mechanical properties of the neo-tissue between time points or processing techniques. CONCLUSIONS: These preliminary data support potential use of decellularized allograft to foster healthy tissue ingrowth within a PLA scaffold, thereby offering a novel solution to current limitations in nipple reconstruction.

1. In this study, we tested the hypothesis that betaine’s methyl-donor properties would reduce homocysteine concentrations, which was recognised in a previous genetics study to be linked to bone quality, and improve bone quality. This was combined with phytase treatment, as phosphorus is critical for bone mineralisation. 2. Using a 2 X 2 arrangement, a total of 1920 Lohmann LSL-lite chickens in 24 replicates of 20 chickens were fed one of 4 diets containing dietary betaine (0 or 1000 mg/kg) and phytase (300 or 1000 FTU/kg) from one day old until end-of-lay. Blood and bone samples were collected at 45 and 70 weeks of age. 3. Hens that were fed betaine had lower plasma homocysteine level (P < 0.05), higher tibia breaking strength (P < 0.05), and higher tibia density (P < 0.05). 4. Egg production and egg quality were excellent throughout the study and were not affected by the dietary treatments. 5. In summary, the addition of dietary betaine was successful at reducing plasma homocysteine concentrations and improving bone strength in laying hens which could be used as an intervention to alleviate welfare concerns.

Hypertension is linked with an increased risk of white matter hyperintensities; however, recent findings have questioned this association. We examined whether hypertension and additional cerebrovascular risk factors impacted on white matter integrity in an inducible hypertensive rat. No white matter hyperintensities were observed on magnetic resonance imaging either alone or in conjunction with ageing and high-fat diet. Aged hypertensive rats that were fed a high-fat diet had moderately reduced fractional anisotropy in the corpus callosum with no overt pathological features. Herein we show that moderate hypertension alone or with additional risk factors has minimal impact on white matter integrity in this model.

High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design. Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals., Highlights • Aged mice were treated with UE2316 using a vehicle-controlled crossover design. • Short-term UE2316 treatment improves spatial memory in a reversible manner. • Contextual fear memory retention was impaired with UE2316. • Contextual fear memory effects persisted following reversal of treatment.