Cellular, molecular and functional characterisation of YAC transgenic mouse models of Friedreich Ataxia

Copyright © 2014 Anjomani Virmouni et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.This article has been made available through the Brunel Open Access Publishing Fund.Background - Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disorder, caused by a GAA repeat expansion mutation within intron 1 of the FXN gene. We have previously established and performed preliminary characterisation of several human FXN yeast artificial chromosome (YAC) transgenic FRDA mouse models containing GAA repeat expansions, Y47R (9 GAA repeats), YG8R (90 and 190 GAA repeats) and YG22R (190 GAA repeats). Methodology/Principal Findings - We now report extended cellular, molecular and functional characterisation of these FXN YAC transgenic mouse models. FXN transgene copy number analysis of the FRDA mice demonstrated that the YG22R and Y47R lines each have a single copy of the FXN transgene while the YG8R line has two copies. Single integration sites of all transgenes were confirmed by fluorescence in situ hybridisation (FISH) analysis of metaphase and interphase chromosomes. We identified significant functional deficits, together with a degree of glucose intolerance and insulin hypersensitivity, in YG8R and YG22R FRDA mice compared to Y47R and wild-type control mice. We also confirmed increased somatic GAA repeat instability in the cerebellum and brain of YG22R and YG8R mice, together with significantly reduced levels of FXN mRNA and protein in the brain and liver of YG8R and YG22R compared to Y47R. Conclusions/Significance - Together these studies provide a detailed characterisation of our GAA repeat expansion-based YAC transgenic FRDA mouse models that will help investigations of FRDA disease mechanisms and therapy.European Union, Ataxia UK and FARA

The rise of the Chinrest and shoulder rest : their influence on violin performance practice

In recent decades there has been a growing interest in the performance practice of the 19th-century repertoire for violin, both in academia and within the HIP movement (Historically Informed Performance Practice). Recent research lacks a demonstrable link between playing positions and the specific techniques regarding the use of the left hand in nineteenth-century violin playing. This is, however, an integral consideration for this topic. Only through practice based research can the link between the intrinsic raison d’être of the postures that are reported in the historical documentation be tested for their effect on playing methods and on their interpretative and rhetorical consequences. Historical documentation is not consistently applied in current practice. While some violinists stubbornly use a chin-off position with repertoire from the early 19th century, others use the chin rest for the same repertoire (perhaps out of convenience). Practice based research is, therefore, a necessary step to arrive at informed conclusions about how nineteenth-century violinists played, as well as what this contributes to the interpretation and execution of works historically associated with specific violinists or violin schools

Transformation in the automotive sector: the management challenges of AI and the digital revolution

Digital transformation in the automotive industry is driving significant change in business models, in customer expectations and in organisations and their workforces. As technology is rapidly progressing, organisations are confronted with massive changes, which are particularly affecting the way in which employees work and the conditions under which they do so. This case considers the rapid digitisation of industry and its consequences for human resource management, specifically in light of the use of artificial intelligence (AI). As a management sciences topic, this case study directs the learner to the automotive sector specifically and its use of AI. Given the significant demands on industry to adopt emerging technologies to remain competitive in today’s global economy, how should the workplace and job design evolve

Evidence of increased islet cell proliferation in patients with recent-onset type 1 diabetes.

addresses: Institute of Biomedical and Clinical Science, Peninsula College of Medicine and Dentistry (University of Exeter), Tamar Science Park, Derriford, Plymouth, UK.The final publication is available at link.springer.com/article/10.1007%2Fs00125-010-1817-6In adults, the rate of beta cell replication is normally very low, but recent evidence suggests that it may increase during insulitis. We therefore studied tissue from donors with recent-onset type 1 diabetes to establish whether islet cell proliferation is increased during the disease process

Tissue cell stress response to obesity and its interaction with late gestational diet

Intra-uterine growth restriction in late pregnancy can contribute to adverse long term metabolic health in the offspring. We utilised an animal (sheep) model of maternal dietary manipulation in late pregnancy, combined with exposure of the offspring to a low activity, obesogenic environment after weaning, to characterise the effects on glucose homeostasis. Dizygotic twin-pregnant sheep were either fed to 60% of requirements (nutrient restriction (R)) or fed ad libitum (~ 140% of requirements (A)) from 110 days gestation until term (~147d). After weaning (~3 months of age), their offspring were kept in either a standard (in order to remain lean) or low activity, obesogenic environment. R mothers gained less weight and produced smaller offspring. As adults, obese offspring were heavier and fatter with reduced glucose tolerance, irrespective of maternal diet. Molecular markers of stress and autophagy in liver and adipose tissue were increased with obesity, with gene expression of hepatic Grp78 and of omental Atf6, Grp78 and Edem1 only being increased in R offspring. In conclusion, the adverse effect of juvenile onset obesity on insulin responsive tissues can be amplified by previous exposure to a suboptimal nutritional environment in utero, thereby contributing to earlier onset of insulin resistance

Sex differences in the regulation of porcine coronary artery tone by perivascular adipose tissue: a role of adiponectin?

Background and Purpose- As there is sexual dimorphism in the regulation of vascular tone, the aim of this present study was to determine whether there are sex differences in perivascular adipose tissue (PVAT) - mediated regulation of the porcine coronary artery (PCA) tone. Experimental Approach- Isometric tension recording system was used to record changes in tone in PCAs. Western blot analysis was performed to examine the expression of adiponectin in PVAT and adiponectin receptors (adipo 1 receptor and adipo 2 receptor) and adiponectin binding protein (APPL1) in PCA. The level of adiponectin released from PVAT was measured using ELISA. Key Results- In the presence of adherent PVAT, contractions to the thromboxane mimetic U46619 and endothelin-1 were significantly reduced in PCAs from females, but not males. In PCAs pre-contracted with U46619, re-addition of PVAT caused relaxation in PCAs from females, but not males. This relaxant response in females was attenuated by combined inhibition of NO synthase (with L-NAME) and cyclooxygenase (with indomethacin). Pre-incubation with an anti-adiponectin antibody abolished the relaxant effects of PVAT. The adiponectin receptor agonist (adipoRon) produced a greater relaxation in PCAs from females compared to males. However, there was no difference in either expression or release of adiponectin from PVAT between sexes. Similarly, there was no difference in expression of adiponectin receptors or the adiponectin receptor adaptor protein APPL1 in PCAs. Conclusion and Implications- These findings demonstrate a clear sex difference in the regulation of coronary artery tone in response to adiponectin receptor stimulation, which may underlie the anticontractile effects of PVAT in females