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McInerney, N.

Publications and source records attributed to McInerney, N..

2 recordsLinked to original sources

Evaluation of adipose-derived stromal cell infused modified-hyaluronic acid scaffolds for post cancer breast reconstruction

IntroductionPrimary breast cancer surgery can compromise aesthetics and quality-of-life for breast cancer patients. While breast reconstruction improves these outcomes, current methods are limited by suboptimal aesthetic outcomes and potential complication risks. There is an urgent clinical need for improved approaches to post surgical reconstruction for breast cancer patients. Adipose-derived stromal cells (ADSCs) with biological scaffolds are being widely evaluated for tissue engineering applications in the field of reconstruction. AimsThis study aimed to assess the biomechanical properties, biocompatibility, adipogenic potential of ADSCs encapsulated in modified hyaluronic acid derivatives in vitro; and efficacy and tissue integration of this construct in vivo in a murine breast cancer and reconstruction model. MethodsADSCs were obtained, with informed consent, from female breast cancer patients undergoing autologous breast reconstruction or cosmetic procedures (n=8) aged 47{+/-}12 years. Modified hyaluronic acid solution was combined with 1x106 ADSCs/mL and crosslinked using hydrogen peroxide and horseradish peroxidase. Youngs modulus, cell viability and adipogenic potential of the cell-loaded hydrogels were assessed in vitro. In vivo, hydrogels combined with murine ADSCs were grafted into a murine breast cancer model and tissues were harvested for immunohistochemistry after 4 weeks. ResultsADSCs were characterised via morphology, Colony forming unit-fibroblast (CFU-F) assay, flow cytometry and multilineage differentiation. The cell-loaded hydrogels had a compressive Youngs modulus of 7.35{+/-}0.96 kPa after 21 days in culture, similar to human breast adipose tissue ([~]10 kPa). High ADSC viability was observed after 21 days in culture, and ADSCs differentiated into mature adipocytes. After 4 weeks in vivo, hydrogels exhibited adipocytes, vascular endothelium, and pericyte-like cells. ConclusionThis study demonstrates the potential suitability of modified hyaluronic acid hydrogels encapsulating ADSCs for adipose tissue engineering for post breast cancer reconstruction.

bioengineering↗

President Roosevelt's lions reveal a century of population fragmentation in Africa's largest carnivore

Over the past century, lion (Panthera leo) populations across Africa have experienced rapid and severe declines. Despite this, East Africa is considered a modern-day lion stronghold. Here, we use whole-genome sequencing of both recent and historical lion populations, primarily collected during the Smithsonians Roosevelt East African (1909-1911) and Rainey (1911-1912) Expeditions, to investigate changes in population structure, connectivity, and diversity over the last [~]100 years in East Africa. We find a clear signal of population fragmentation when comparing historical (1896-1946) and recent (1990-present) lion populations. Our analyses reveal genetic distinctions between remaining lion populations in Kenya and Tanzania and document loss of genetic diversity over time including reduced heterozygosity and the accumulation of runs of homozygosity. We detect a severe bottleneck in both Kenya and Tanzania approximately 25 generations ago, coinciding with a severe rinderpest outbreak in the region that is known to have decimated bovid and ultimately carnivore populations in the area. Nevertheless, modern lions in East Africa still exhibit overall high levels of diversity and low levels of inbreeding. Our results provide direct evidence of the effects of increasing habitat fragmentation and the significance of temporal data for contextualizing current patterns of population connectivity and diversity.

evolutionary biology↗