34 research outputs found
Comparison of the endocranial- and brain volumes in brachycephalic dogs, mesaticephalic dogs and Cavalier King Charles spaniels in relation to their body weight
BACKGROUND: A number of studies have attempted to quantify the relative volumes of the endocranial volume and brain parenchyma in association with the pathogenesis of the Chiari-like malformation (CLM) in the Cavalier King Charles spaniel (CKCS). In our study we examine the influence of allometric scaling of the brain and cranial cavity volume on morphological parameters in different dog breeds. MRI scans of 110 dogs (35 mesaticephalic dogs, 35 brachycephalic dogs, 20 CKCSs with SM, and 20 CKCSs without SM) have been used to create 3-dimensional volumetric models of skull and brain parts. Volumes were related to body weight calculating the adjusted means for different breeds.
RESULTS: There was a strong global dependency of all volumes to body weight (P<0.0001). The adjusted means of the absolute and relative volumes of brain parenchyma and cranial compartments are not significantly larger in CKCSs in comparison to brachycephalic and mesaticephalic dogs. A difference in absolute or relative volumes between CKCSs with and without SM after relating these values to body weight could not be identified. The relative volume of the hindbrain parenchyma (caudal fossa parenchyma percentage) was larger in brachycephalic dogs than in CKCSs, without causing herniation or SM.
CONCLUSION: An influence of body weight exist in dogs, which can be sufficiently large to render conclusions on the difference in volumes of the brain and skull unsafe unless some account of the body weight is taken in the analysis. The results of this study challenge the role of overcrowding for the development of SM in dogs
The genetic overlap between mood disorders and cardiometabolic diseases: a systematic review of genome wide and candidate gene studies
© The Author(s) 2017 This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material.Meta-analyses of genome-wide association studies (meta-GWASs) and candidate gene studies have identified genetic variants associated with cardiovascular diseases, metabolic diseases and mood disorders. Although previous efforts were successful for individual disease conditions (single disease), limited information exists on shared genetic risk between these disorders. This article presents a detailed review and analysis of cardiometabolic diseases risk (CMD-R) genes that are also associated with mood disorders. First, we reviewed meta-GWASs published until January 2016, for the diseases ‘type 2 diabetes, coronary artery disease, hypertension’ and/or for the risk factors ‘blood pressure, obesity, plasma lipid levels, insulin and glucose related traits’. We then searched the literature for published associations of these CMD-R genes with mood disorders. We considered studies that reported a significant association of at least one of the CMD-R genes and ‘depression’ or ‘depressive disorder’ or ‘depressive symptoms’ or ‘bipolar disorder’ or ‘lithium treatment response in bipolar disorder’, or ‘serotonin reuptake inhibitors treatment response in major depression’. Our review revealed 24 potential pleiotropic genes that are likely to be shared between mood disorders and CMD-Rs. These genes include MTHFR, CACNA1D, CACNB2, GNAS, ADRB1, NCAN, REST, FTO, POMC, BDNF, CREB, ITIH4, LEP, GSK3B, SLC18A1, TLR4, PPP1R1B, APOE, CRY2, HTR1A, ADRA2A, TCF7L2, MTNR1B and IGF1. A pathway analysis of these genes revealed significant pathways: corticotrophin-releasing hormone signaling, AMPK signaling, cAMP-mediated or G-protein coupled receptor signaling, axonal guidance signaling, serotonin or dopamine receptors signaling, dopamine-DARPP32 feedback in cAMP signaling, circadian rhythm signaling and leptin signaling. Our review provides insights into the shared biological mechanisms of mood disorders and cardiometabolic diseases
The Toroid Cavity NMR Detector
A cylindrical toroid cavity has been developed as an NMR detector for investigations at high temperature and high pressure in metal vessel probes. With toroid cavity detectors, resonance frequencies up to 400 MHz can easily be attained, which makes them particularly useful for high-field 1H and 19F spectroscopy. Typically, static half-height linewidths of 1.5 Hz are achieved, as measured on 1H with standard solutions in cylindrical pressure vessels. Based on the radial dependency of the B1 field inside a toroid detector, a mathematical equation was derived that precisely predicts the signal intensity as a function of the pulse width. Inversion-recovery measurements of the T1 relaxation time of compressed gases (methane and hydrogen) were conducted by using composite inversion pulses. The results demonstrated the utility of toroid cavities for quantitative measurements in pressure probes. Pressures up to 300 bar have been used successfully. Because of the strength and regularity of the B1 gradient, the toroid cavity detector is also suitable for one dimensional rotating-frame NMR microscopy. A spatial resolution down to a few micrometers can be achieved. The spin concentration and spatial distribution of a chloroform solution were accurately reconstructed from two-dimensional 1H NMR data. Another similarly accurate but even stronger B1 gradient evolves as a result of the skin effect during high-frequency current transmission inside the central conductor. This gradient makes it possible to perform rotating-frame microscopy inside the central conductor, as demonstrated with 63Cu NMR spectroscopy
Recommended from our members
Near-Electrode Imager
An apparatus, near-electrode imager, for employing nuclear magnetic resonance imaging to provide in situ measurements of electrochemical properties of a sample as a function of distance from a working electrode. The near-electrode imager use the radio frequency field gradient within a cylindrical toroid cavity resonator to provide high-resolution nuclear magnetic resonance spectral information on electrolyte materials