Deuterium imaging of the Warburg effect at sub-millimolar concentrations by joint processing of the kinetic and spectral dimensions

Deuterium metabolic imaging (DMI) is a promising molecular MRI approach, which follows the administration of deuterated substrates and their metabolization. [6,6’-2H2]-glucose for instance is preferentially converted in tumors to [3,3’-2H2]-lactate as a result of the Warburg effect, providing a distinct resonance whose mapping using time-resolved spectroscopic imaging can diagnose cancer. The MR detection of low-concentration metabolites such as lactate, however, is challenging. It has been recently shown that multi-echo balanced steady-state free precession (ME-bSSFP) increases the signal-to-noise ratio (SNR) of these experiments approximately threefold over regular chemical shift imaging; the present study examines how DMI's sensitivity can be increased further by advanced processing methods. Some of these, such as compressed sensing multiplicative denoising and block-matching/3D filtering, can be applied to any spectroscopic/imaging methods. Sensitivity-enhancing approaches were also specifically tailored to ME-bSSFP DMI, by relying on priors related to the resonances' positions and to features of the metabolic kinetics. Two new methods are thus proposed that use these constraints for enhancing the sensitivity of both the spectral images and the metabolic kinetics. The ability of these methods to improve DMI is evidenced in pancreatic cancer studies carried at 15.2 T, where suitable implementations of the proposals imparted eightfold or more SNR improvement over the original ME-bSSFP data, at no informational cost. Comparisons with other propositions in the literature are briefly discussed

“Losing Faith in My Body”: Body Image in Individuals Diagnosed with End-Stage Renal Disease as Reflected in Drawings and Narratives

Chronic kidney disease (CKD) and the dependency on dialysis is an abrupt life-changing event that harms a patient’s life (e.g., social relationships, work, and well-being). This study aimed to examine how individuals who undergo chronic dialysis due to failure end-stage renal disease perceive their bodies, as reflected in drawings and narratives. Following ethical approval and signing a consent form to participate in the study, 29 adults between the ages of 20 and 85 who have undergone dialysis filled out an anonymous questionnaire that consisted of the following measures: The Center for Epidemiological Studies—Depression (CES-D), The Multidimensional Body-Self Relations Questionnaire (MBSRQ), and The MOS 36-Item Short-Form Health Survey (SF-36). After completion, they were asked to draw their self-figure before and after being diagnosed and narrate it. The data were quantitatively and narratively analyzed. The results revealed high levels of depression and concerns regarding body fitness and weight. Few significant differences were noted between self-figured drawings before and after the diagnosis, such as the body line and gender markers. Additionally, Fitness Evaluation and Overweight Preoccupation were significant among the participants

Genetic and behavioural factors affecting interpopulation colour pattern variation in two congeneric chameleon species

We conducted a study on interpopulation variation of colour patterns in two congeneric chameleon species, which have an analogous life history. Both species are able to rapidly change colour pattern, and their context-dependent colour patterns often vary across a wide geographical range. Specifically, we tested four hypotheses that can explain the observed interpopulation variation of colour patterns by a series of behavioural field trials where the colour patterns of individuals were recorded and later analysed by a deep neural network algorithm. We used redundancy analysis to relate genetic, spectral and behavioural predictors to interpopulation colour pattern distance. Our results showed that both isolation by distance (IBD) and alternative mating tactics were significant predictors for interpopulation colour pattern variation in Chamaeleo chamaeleon males. By contrast, in Chamaeleo dilepis, the interpopulation colour pattern variation was largely explained by IBD, and evidence for alternative mating tactics was absent. In both chameleon species, the environmental colours showed no evidence of influencing chameleon interpopulation colour pattern variation, regardless of sex or behavioural context. This contrasting finding suggests that interpopulation context-dependent colour pattern variations in each species are maintained under a different set of selective pressures or circumstances