Publications by authors named "Megan Pendleton"

In this study, we used micro-CT-based finite element analysis to investigate the biomechanical effects of radiation on the microstructure and mechanical function of murine lumbar vertebrae. Specifically, we evaluated vertebral microstructure, whole-bone stiffness, and cortical-trabecular load sharing in the L5 vertebral body of mice exposed to ionizing radiation 11 days post exposure (5 Gy total dose;  = 13) and controls ( = 14). Our findings revealed the irradiated group exhibited reduced trabecular bone volume and microstructure ( < 0.

View Article and Find Full Text PDF

Introduction: Despite efforts to advance clinical research through collaboration between Latin and North American partners, there remains persistent barriers to performing investigative work. To overcome these obstacles, a team of over 100 surgeon-leaders from 18 Latin American countries founded the Asociación de Cirujanos Traumatólogos de las Américas (ACTUAR). One of ACTUAR's first major collaborative projects, initiated in 2018, was a prospective, observational, multicenter study evaluating quality of life after open tibia fracture management.

View Article and Find Full Text PDF

Humans are exposed to ionizing radiation via spaceflight or cancer radiotherapy, and exposure from radiotherapy is known to increase risk of skeletal fractures. Although irradiation can reduce trabecular bone mass, alter trabecular microarchitecture, and increase collagen cross-linking, the relative contributions of these effects to any loss of mechanical integrity remain unclear. To provide insight, while addressing both the monotonic strength and cyclic-loading fatigue life, we conducted total-body, acute, gamma-irradiation experiments on skeletally mature (17-week-old) C57BL/6J male mice ( = 84).

View Article and Find Full Text PDF

Spaceflight is a unique environment that includes at least two factors which can negatively impact skeletal health: microgravity and ionizing radiation. We have previously shown that a diet supplemented with dried plum powder (DP) prevented radiation-induced bone loss in mice. In this study, we investigated the capacity of the DP diet to prevent bone loss in mice following exposure to simulated spaceflight, combining microgravity (by hindlimb unloading) and radiation exposure.

View Article and Find Full Text PDF

Bone can become brittle when exposed to ionizing radiation across a wide range of clinically relevant doses that span from radiotherapy (accumulative 50 Gy) to sterilization (~35,000 Gy). While irradiation-induced embrittlement has been attributed to changes in the collagen molecular structure, the relative role of collagen fragmentation versus non-enzymatic collagen crosslinking remains unclear. To better understand the effects of radiation on the bone material without cellular activity, we conducted an ex vivo x-ray radiation experiment on excised mouse lumbar vertebrae.

View Article and Find Full Text PDF
Article Synopsis
  • The text discusses a new method for testing the bone quality of small animals, specifically mouse vertebrae, through cyclic mechanical loading methods.
  • The new method uses precise 3D-printed support structures and pivotable loading to ensure consistent and accurate testing results.
  • Results showed that this method significantly reduced variability in the fatigue life measurements of the vertebrae, indicating it could provide better insights into bone quality compared to existing techniques.
View Article and Find Full Text PDF