Detection and Characterization of Endplate Structural Defects on CT: A Diagnostic Accuracy Study.

Study Design: Diagnostic test study.

Objective: To determine the reliability and validity or diagnostic accuracy of two previously described endplate structural defect (EPSD) assessment methods.

Summary Of Background Data: Studies of EPSD may further the understanding of pathoanatomic mechanisms underlying back pain.

Thoracolumbar Vertebral Endplate Defect Morphology: A Descriptive Study of Human Cadaveric Spines Using Micro-Computed Tomography.

Study Design: A descriptive, cross-sectional cadaver study.

Objective: This study aimed to provide a thorough depiction of vertebral endplate defects classified based on their morphologic features and reported with respect to size, location, and prevalence in the human cadaveric spines of older adults.

Summary Of Background Data: Back pain has been associated with vertebral endplate defects; however, findings have been inconsistent.

Effects of risk factors on evoked pain patterns in rat models of experimental knee osteoarthritis.

Pain experiences in patients with knee osteoarthritis (OA) may be influenced differently by OA risk factors, reducing the translatability of preclinical research into the clinic. Our objective was to contrast evoked pain patterns after exposure to different OA risk factors including acute joint trauma, chronic instability, or obesity/metabolic syndrome using rat models of experimental knee OA. We tested longitudinal patterns of evoked pain behaviors (knee pressure pain threshold and hindpaw withdrawal threshold) in young male rats exposed to different OA-inducing risk factors including (1) nonsurgical joint trauma (impact-induced anterior cruciate ligament (ACL) rupture); (2) surgical joint destabilization (ACL + medial meniscotibial ligament transection); and (3) high fat/sucrose (HFS) diet-induced obesity.

Effect of Memantine Treatment and Combination with Vitamin D Supplementation on Body Composition in the APP/PS1 Mouse Model of Alzheimer's Disease Following Chronic Vitamin D Deficiency.

Background: Vitamin D deficiency and altered body composition are common in Alzheimer's disease (AD). Memantine with vitamin D supplementation can protect cortical axons against amyloid-β exposure and glutamate toxicity.

Objective: To study the effects of vitamin D deprivation and subsequent treatment with memantine and vitamin D enrichment on whole-body composition using a mouse model of AD.

Microbial Diversity of Impact-Generated Habitats.

Impact-generated lithologies have recently been identified as viable and important microbial habitats, especially within cold and arid regions such as the polar deserts on Earth. These unique habitats provide protection from environmental stressors, such as freeze-thaw events, desiccation, and UV radiation, and act to trap aerially deposited detritus within the fissures and pore spaces, providing necessary nutrients for endoliths. This study provides the first culture-independent analysis of the microbial community structure within impact-generated lithologies in a Mars analog environment, involving the analysis of 44,534 16S rRNA sequences from an assemblage of 21 rock samples that comprises three shock metamorphism categories.

Rapid in vivo whole body composition of rats using cone beam μCT.

Precise, noninvasive analysis and quantification of in vivo body composition is essential for research involving longitudinal, small-animal disease models. We investigated the feasibility and precision of a rapid, flat-panel μCT scanner to report whole body adipose tissue volume (ATV), lean tissue volume (LTV), skeletal tissue volume (STV), and bone mineral content (BMC) in 25 postmortem female and 52 live male Sprague-Dawley rats. μCT images, acquired in three 90-mm segments and reconstructed with 308 μm of isotropic voxel spacing, formed contiguous image volumes of each entire rat specimen.

The role of Akt1 in terminal stages of endochondral bone formation: angiogenesis and ossification.

Longitudinal bone growth is the result of endochondral bone formation which takes place in the growth plate. The rate of chondrocyte proliferation and hypertrophy, vascular invasion with the formation of primary ossification centers and cartilage replacement by bone tissue are all important processes required for normal growth. We have shown a role for the PI3K signaling pathway in chondrocyte hypertrophy and bone growth in tibia explant cultures.

In vivo micro-CT analysis of bone remodeling in a rat calvarial defect model.

The rodent calvarial defect model is commonly used to investigate bone regeneration and wound healing. This study presents a micro-computed tomography (micro-CT) methodology for measuring the bone mineral content (BMC) in a rat calvarial defect and validates it by estimating its precision error. Two defect models were implemented.

Ionization chamber volume determination and quality assurance using micro-CT imaging.

Ion chamber dosimetry requires a high degree of precision, at all steps within the dosimetric process, in order to ensure accurate dose measurements. This work presents a novel technique for ion chamber volume determination and quality assurance, using micro-computed tomography (micro-CT). Four nominally identical Exradin A1SL chambers (0.

A quality assurance phantom for the performance evaluation of volumetric micro-CT systems.

Small-animal imaging has recently become an area of increased interest because more human diseases can be modeled in transgenic and knockout rodents. As a result, micro-computed tomography (micro-CT) systems are becoming more common in research laboratories, due to their ability to achieve spatial resolution as high as 10 microm, giving highly detailed anatomical information. Most recently, a volumetric cone-beam micro-CT system using a flat-panel detector (eXplore Ultra, GE Healthcare, London, ON) has been developed that combines the high resolution of micro-CT and the fast scanning speed of clinical CT, so that dynamic perfusion imaging can be performed in mice and rats, providing functional physiological information in addition to anatomical information.