Do regional brain volumes and major depressive disorder share genetic architecture?:A study of Generation Scotland (<i>n</i>=19,762), UK Biobank (<i>n</i>=24,048) and the English Longitudinal Study of Ageing (<i>n</i>=5,766)

Major depressive disorder (MDD) is a heritable and highly debilitating condition. It is commonly associated with subcortical volumetric abnormalities, the most replicated of these being reduced hippocampal volume. Using the most recent published data from Enhancing Neuroimaging Genetics through Meta-analysis (ENIGMA) consortium's genome-wide association study of regional brain volume, we sought to test whether there is shared genetic architecture between seven subcortical brain volumes and intracranial volume (ICV) and MDD. We explored this using linkage disequilibrium score regression, polygenic risk scoring (PRS) techniques, Mendelian randomisation (MR) analysis and BUHMBOX. Utilising summary statistics from ENIGMA and Psychiatric Genomics Consortium, we demonstrated that hippocampal volume was positively genetically correlated with MDD (rG=0.46, P=0.02), although this did not survive multiple comparison testing. None of the other six brain regions studied were genetically correlated and amygdala volume heritability was too low for analysis. Using PRS analysis, no regional volumetric PRS demonstrated a significant association with MDD or recurrent MDD. MR analysis in hippocampal volume and MDD identified no causal association, however, BUHMBOX analysis identified genetic subgrouping in GS:SFHS MDD cases only (P=0.00281). In this study, we provide some evidence that hippocampal volume and MDD may share genetic architecture in a subgroup of individuals, albeit the genetic correlation did not survive multiple testing correction and genetic subgroup heterogeneity was not replicated. In contrast, we found no evidence to support a shared genetic architecture between MDD and other regional subcortical volumes or ICV

Bioreactor for microalgal cultivation systems: strategy and development

Microalgae are important natural resources that can provide food, medicine, energy and various bioproducts for nutraceutical, cosmeceutical and aquaculture industries. Their production rates are superior compared to those of terrestrial crops. However, microalgae biomass production on a large scale is still a challenging problem in terms of economic and ecological viability. Microalgal cultivation system should be designed to maximize production with the least cost. Energy efficient approaches of using light, dynamic mixing to maximize use of carbon dioxide (CO2) and nutrients and selection of highly productive species are the main considerations in designing an efficient photobioreactor. In general, optimized culture conditions and biological responses are the two overarching attributes to be considered for photobioreactor design strategies. Thus, fundamental aspects of microalgae growth, such as availability of suitable light, CO2 and nutrients to each growing cell, suitable environmental parameters (including temperature and pH) and efficient removal of oxygen which otherwise would negatively impact the algal growth, should be integrated into the photobioreactor design and function. Innovations should be strategized to fully exploit the wastewaters, flue-gas, waves or solar energy to drive large outdoor microalgae cultivation systems. Cultured species should be carefully selected to match the most suitable growth parameters in different reactor systems. Factors that would decrease production such as photoinhibition, self-shading and phosphate flocculation should be nullified using appropriate technical approaches such as flashing light innovation, selective light spectrum, light-CO2 synergy and mixing dynamics. Use of predictive mathematical modelling and adoption of new technologies in novel photobioreactor design will not only increase the photosynthetic and growth rates but will also enhance the quality of microalgae composition. Optimizing the use of natural resources and industrial wastes that would otherwise harm the environment should be given emphasis in strategizing the photobioreactor mass production. To date, more research and innovation are needed since scalability and economics of microalgae cultivation using photobioreactors remain the challenges to be overcome for large-scale microalgae production

A fast approach for antenna phase center evaluation

Accurate evaluation of the Antenna Phase Center (APC) position is a key issue in radar applications. In this work we propose an approach for the APC position measurement in anechoic chamber. The presented method allows overcoming some limitations of the classical algorithm known as Two Point Approach, and it has been tested on two X-band antennas: a standard horn antenna and the three-horn array antenna mounted onboard the TELAER airborne Synthetic Aperture Radar system

Hepatic mitochondrial bioenergetic and dynamic behaviour adaptations in response to high-fat feeding

Introduction: High-fat feeding induces hepatic lipid accumulation associated with concomitant mitochondrial fat oxidation enhancement and electron-chain impairment that result in excessive formation of reactive oxygen species. Little is known about hepatic mitochondrial dynamic behaviours adaptation to high-fat feeding. Mitochondria are dynamic organelles that frequently undergo fission and fusion processes, imbalances in which have recently emerged as important etiological factors in obesity and insulin-resistance. Bearing in mind that fish-oil feeding has anti-steatotic effects, the present work aimed to evaluate the effects of high-lard (mainly saturated fatty acids) and high-fish-oil (mainly omega-3 polyunsaturated fatty acids) diets on both hepatic mitochondrial bioenergetic and dynamic behaviour. Methods: Hepatic lipid accumulation was monitored in rats fed a high-lard or high-fish-oil (40% J/J) diet for 6 weeks. Mitochondrial functions were assessed by evaluating FADH2 linked respiratory rates, fatty acid oxidation rates, energetic efficiency (by measuring basal and fatty acid induced proton leak kinetics), and oxidative stress (by measuring H2O2 release and aconitase activity). Mitochondrial dynamics behaviour was assessed by analysing the proteins relevant to the processes of fusion (MFN2, OPA1) and fission (DRP1, Fis1) (by western blot and immunohistochemical analysis). Results: Hepatic lipid accumulation, electron chain impairment and oxidative stress induced by high-lard diet were associated with both decreased fatty acid induced proton leak and a shift toward mitochondrial fission processes (decreased MFN2 content and increased DRP1 and Fis1 content). On the other hand, the anti-steatotic effect of high-fish oil feeding was associated with mild uncoupling (increases in both basal and fatty acid induced proton leak kinetics), oxidative stress prevention and increased mitochondrial fusion processes. Conclusions: Fission phenotype and increased energetic efficiency are associated with the steatotic effect of high-lard diet, whereas fusion phenotype and decreased energetic efficiency contributed to the anti-steatotic effect of high-fish oil diet

Diet supplementation with donkey milk upregulates liver mitochondrial uncoupling, reduces energy efficiency and improves antioxidant and antiinflammatory defences in rats.

Dietary PUFA, mainly those of the n-3 family, are known to play essential roles in the maintenance of energy balance and in the reduction of body fat deposition through the upregulation of mitochondrial uncoupling that is the main source of reactive oxygen species. We hypothesized that rat supplementation with raw donkey’s milk (DM), characterized by low-fat content and higher n3:n6 ratio, may affect energy balance, lipid metabolism, and prooxidant status as compared to animals treated with cow’s milk. In the present study, the effects of drinking raw DM (for 4 weeks) on energy balance, lipid metabolism, antiinflammatory, and antioxidant/ detoxifying defences was compared to that produced by rat intake of an iso-energetic amount of raw cow’s milk. The hypolipidemic effect produced by DM paralleled with the enhanced mitochondrial activity/proton leakage and with the increased activity or expression of mitochondrial markers namely, carnitine palmitoyl transferase and uncoupling protein 2. The association of decreased energy efficiency with reduced proinflammatory signs (TNF- and LPS levels) with the significant increase antioxidant (total thiols) and detoxifying enzyme activities (glutathione-S-transferase NADH quinone oxidoreductase) in DM-treated animals, indicated that beneficial effects were attributable, at least in part, to the activation of nuclear factor 2 erythroid-related factor 2 pathway