Biology subjects

Bodey, A. J.

Publications and source records attributed to Bodey, A. J..

4 recordsLinked to original sources

bioRxiv2024

Cryogenic non-invasive 3D X-ray phase-contrast imaging of unfixed, intact mouse joints reveals shifting chondrocyte hypertrophy across the endochondral interface

Objectivesi) develop and use a new cryogenically-enhanced phase contrast method to visualise hyaline articular cartilage (HAC); ii) to measure HAC, articular calcified cartilage (ACC) and total articular cartilage thicknesses in male STR/Ort (osteoarthritis, OA) and CBA (healthy) mouse tibial epiphyses, reflecting divergent OA predisposition, at three age timepoints chosen to reflect pre-OA, OA onset and late-progression; iii) to compare HAC, trans-zonal and ACC 3D chondrocyte anatomy in tibial epiphyses. MethodsSTR/Ort and CBA mouse knees (n=4 per age and strain group) were synchrotron-CT scanned at high-resolution while fresh frozen, without staining, fixation, dissection or dehydration of the joint capsule. Both cartilage thickness and cellular characteristics (chondrocyte n=420) were manually measured and statistically compared (SPSS). ResultsCryo-enhanced phase contrast allowed cartilage to be seen in full thickness with cellular detail. HAC was thicker in STR/Ort than age-matched CBA mice in 16/24 knee joint compartments and timepoints (all p<0.04). In contrast, HAC was thicker only in the posterior lateral femur of CBA mice at 10weeks (p<0.001, Table 1). ACC and total cartilage were also thicker in STR/Orts. Trans-zonal chondrocytes were smaller than ACC and HAC chondrocytes (p-values<0.001, volumes 878, 1,567m3 and 1,348m3 respectively). O_TBL View this table: org.highwire.dtl.DTLVardef@191d5a9org.highwire.dtl.DTLVardef@162523borg.highwire.dtl.DTLVardef@4b7caorg.highwire.dtl.DTLVardef@1be6005org.highwire.dtl.DTLVardef@192143d_HPS_FORMAT_FIGEXP M_TBL O_FLOATNOTABLE 1:C_FLOATNO O_TABLECAPTIONCondylar compartments in which HAC thickness was measured, and the presence or absence of a significant difference between STR/Ort and CBA mouse strains. * indicates a significant difference between strains (p<0.05). Note that the posterior lateral femur at 10 weeks of age is the only region in which STR/Ort mice have significantly thinner HAC than CBA mice. C_TABLECAPTION C_TBL ConclusionsCryogenically-enhanced phase-contrast imaging allowed cellular detail to be seen in 3D as never before in HAC in this (or any other) model. Our findings challenge current understanding by associating STR/Ort OA vulnerability with regions of thick, rather than thinning-with-age, cartilage. Our data affirm an association between excessively hypertrophic chondrocytes and OA is present in STR/Ort mice.

physiology↗

bioRxiv2022

"Same same but different"Exploring evolutionary and ecological causes of eye diversification in bumblebees

Bees rely heavily on vision during most of their interaction with the environment, but so far, visual abilities have not been included into functional investigations of these crucial pollinators. This is probably due to the lack of comprehensive and phylogenetically-controlled quantification of visual traits across species. In the present study, we used high-throughput micro-CT tools to quantify, compare and understand the diversity of visual traits of compound eyes in bumblebees. Visual systems of bumblebees were far from identical, with variations across sizes, castes and species. While phylogenetic proximity poorly supported interspecific variations, these were better explained by two ecological factors: social parasitism and habitat. The eye parameter - a metric that measures the relative investment of a compound eye into resolution or sensitivity - was lower in queens of social parasitic species than of non-parasitic species. Workers of species associated with forested habitat had distinct visual traits, including a higher eye parameter, than those of species living in open landscapes. These diverse visual traits are likely to provide selective advantages to bumblebees given their specific ecological requirements. We thus propose that social parasitism and forest habitat are drivers of the diversification of compound eyes in bumblebees. Finally, we discuss how the present study can inspire trait-based approaches in ecology and conservation biology.

neuroscience↗

bioRxiv2022

Allometric scaling of a superposition eye optimises sensitivity and acuity in large and small hawkmoths

Animals vary widely in body size across and within species. This has consequences in large and small individuals for the function of organs and body parts. How these scale in relation to body size reveals evolutionary investment strategies, often resulting in trade-offs between functions. Eyes exemplify these trade-offs, as they are limited by their absolute size in two key performance features: sensitivity and spatial acuity. Previous studies of the 3D structure of apposition compound eyes, which are ideal models for allometric studies due to their size polymorphism, revealed that allometric scaling improves both local resolution and visual sensitivity in larger bumblebees (Taylor et al., 2019). Here, we build on the established methods and results to investigate allometric scaling in superposition compound eyes - the second prominent eye type in insects - for the first time. Our research highlights a surprising strategy to cope with the challenge of trading off sensitivity and spatial resolution in small eyes, as we show that the eyes of the hummingbird hawkmoth retain an optimal balance of these performance measures across all body sizes.

neuroscience↗

bioRxiv2018

Bumblebee visual allometry results in locally improved resolution and globally improved sensitivity

The quality of visual information that is available to an animal is limited by the size of its eyes. Differences in eye size can be observed even between closely related individuals but we understand little about how this affects visual quality. Insects are good models for exploring the effects of size on visual systems because many species exhibit size polymorphism, which modifies both the size and shape of their eyes. Previous work in this area has been limited, however, due to the challenge of determining the 3D structure of eyes. To address this, we have developed a novel method based on x-ray tomography to measure the 3D structure of insect eyes and calculate their visual capabilities. We investigated visual allometry in the bumblebee Bombus terrestris and found that size affects specific aspects of visual quality including binocular overlap, optical sensitivity across the field of view, and visual resolution in the dorsofrontal visual field. This holistic study on eye allometry reveals that differential scaling between different eye areas provides substantial flexibility for larger bumblebees to have improved visual capabilities.

neuroscience↗