62 research outputs found

    Structural basis for phosphorylation and lysine acetylation cross-talk in a kinase motif associated with myocardial ischemia and cardioprotection

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    Myocardial ischemia and cardioprotection by ischemic pre-conditioning induce signal networks aimed at survival or cell death if the ischemic period is prolonged. These pathways are mediated by protein post-translational modifications that are hypothesized to cross-talk with and regulate each other. Phosphopeptides and lysine-acetylated peptides were quantified in isolated rat hearts subjected to ischemia or ischemic pre-conditioning, with and without splitomicin inhibition of lysine deacetylation. We show lysine acetylation (acetyl-Lys)-dependent activation of AMP-activated protein kinase, AKT, and PKA kinases during ischemia. Phosphorylation and acetyl-Lys sites mapped onto tertiary structures were proximal in >50% of proteins investigated, yet they were mutually exclusive in 50 ischemic pre-conditioning- and/or ischemia-associated peptides containing the KXXS basophilic protein kinase consensus motif. Modifications in this motif were modeled in the C terminus of muscle-type creatine kinase. Acetyl-Lys increased proximal dephosphorylation by 10-fold. Structural analysis of modified muscle-type creatine kinase peptide variants by two-dimensional NMR revealed stabilization via a lysine-phosphate salt bridge, which was disrupted by acetyl-Lys resulting in backbone flexibility and increased phosphatase accessibility

    A brown dwarf candidate in the Praesepe Open Cluster

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    We present optical and infrared observations of RPr1, a faint (I = 21.01) and very red object (I - K = 4.57) discovered in a deep CCD survey, covering an area of 800 square arcmin of the Praesepe open cluster. A low resolution spectrum shows that RPr1 is a very late object, the latest object in Praesepe for which a spectrum has been taken to date. Our estimates give a mass between 0.063 and 0.084 solar masses, and indicate that RPr1 may turn out to be the first brown dwarf in this cluster.Comment: 7 pages, 3 Postscript figures, to be published in The Astrophysical Journal Letter

    What’s in a “research passport”? A collaborative autoethnography of institutional approvals in public involvement in research

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    © 2016 Laterza et al. Background In the growing literature on public involvement in research (PIR), very few works analyse PIR organizational and institutional dimensions in depth. We explore the complex interactions of PIR with institutions and bureaucratic procedures, with a focus on the process of securing institutional permissions for members of the public (we refer to them as “research partners”) and academics involved in health research. Methods We employ a collaborative autoethnographic approach to describe the process of validating “research passports” required by UK NHS trusts, and the individual experiences of the authors who went through this journey– research partners and academics involved in a qualitative study of PIR across eight health sciences projects in England and Wales. Results Our findings show that research partners encountered many challenges, as the overall bureaucratic procedures and the emotional work required to deal with them proved burdensome. The effects were felt by the academics too who had to manage the whole process at an early stage of team building in the project. Our thematic discussion focuses on two additional themes: the emerging tensions around professionalisation of research partners, and the reflexive effects on PIR processes. Conclusions In the concluding section, we make a number of practical recommendations. Project teams should allow enough time to go through all the hurdles and steps required for institutional permissions, and should plan in advance for the right amount of time and capacity needed from project leaders and administrators. Our findings are a reminder that the bureaucratic and organisational structures involved in PIR can sometimes produce unanticipated and unwanted negative effects on research partners, hence affecting the overall quality and effectiveness of PIR. Our final recommendation to policy makers is to focus their efforts on making PIR bureaucracy more inclusive and ultimately more democratic

    The Epidemiology of COVID-19 in the Gansu and Jinlin Provinces, China

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    The COVID-19 outbreak has become a pandemic. The outbreak was able to be controlled in China by mid-April through the implementation of critical measures; however, significant reverse transmission has resulted in hot spots perturbing prevention and control. To date, there have only been a total of 92 indigenous COVID-19 cases confirmed in the Gansu Province, which is considered to be a consequence of the strict screening approach applied during the outbreak. The emergency response level to COVID-19 were able to be decreased from high to low, despite some relatively minor reverse transmission cases from other countries in March 2020. The stringent preparative measures undertaken by the Gansu authorities, involving high-level, streamlined cooperation between the transportation, quarantine, and medical resource departments, have underpinned this success. There has been an emergence of clusters of freshly infected COVID-19 patients in the Jilin Province in northeast China. The single largest cluster has been in Shulan of the Jilin Province, involving 43 confirmed infections. A strict lockdown was implemented immediately. The source of the current outbreak of COVID-19 is suggested to be travelers returning from Russia. The current strategy from the Chinese authorities is aimed at preventing reverse transmission via international importation to avert a rebound of COVID-19 in China. These data highlight the need for an exceptionally high level of vigilance and for a pre-emptive response that is informative for the development of policy to prevent a second and further waves of infections in general

    FTO associations with obesity and telomere length

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    Abstract This review examines the biology of the Fat mass- and obesity-associated gene (FTO), and the implications of genetic association of FTO SNPs with obesity and genetic aging. Notably, we focus on the role of FTO in the regulation of methylation status as possible regulators of weight gain and genetic aging. We present a theoretical review of the FTO gene with a particular emphasis on associations with UCP2, AMPK, RBL2, IRX3, CUX1, mTORC1 and hormones involved in hunger regulation. These associations are important for dietary behavior regulation and cellular nutrient sensing via amino acids. We suggest that these pathways may also influence telomere regulation. Telomere length (TL) attrition may be influenced by obesity-related inflammation and oxidative stress, and FTO gene-involved pathways. There is additional emerging evidence to suggest that telomere length and obesity are bi-directionally associated. However, the role of obesity risk-related genotypes and associations with TL are not well understood. The FTO gene may influence pathways implicated in regulation of TL, which could help to explain some of the non-consistent relationship between weight phenotype and telomere length that is observed in population studies investigating obesity

    The Role of Inflammation and Myeloperoxidase-Related Oxidative Stress in the Pathogenesis of Genetically Triggered Thoracic Aortic Aneurysms

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    Genetically triggered thoracic aortic aneurysms (TAAs) are usually considered to exhibit minimal levels of inflammation. However, emerging data demonstrate that specific features of an inflammatory response can be observed in TAA, and that the extent of the inflammatory response can be correlated with the severity, in both mouse models and in human studies. Myeloperoxidase (MPO) is a key mediator of the inflammatory response, via production of specific oxidative species, e.g., the hypohalous acids. Specific tissue modifications, mediated by hypohalous acids, have been documented in multiple cardiovascular pathologies, including atherosclerosis associated with coronary artery disease, abdominal aortic, and cerebral aneurysms. Similarly, data are now emerging that show the capacity of MPO-derived oxidative species to regulate mechanisms important in TAA pathogenesis, including alterations in extracellular matrix homeostasis, activation of matrix metalloproteinases, induction of endothelial dysfunction and vascular smooth muscle cell phenotypic switching, and activation of ERK1/2 signaling. The weight of evidence supports a role for inflammation in exacerbating the severity of TAA progression, expanding our understanding of the pathogenesis of TAA, identifying potential biomarkers for early detection of TAA, monitoring severity and progression, and for defining potential novel therapeutic targets

    Sex-specific educational attainment is associated with telomere length in an Australian rural population

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    BACKGROUND: There is limited understanding on whether and how socioeconomic status (SES), particularly educational attainment and household income, impacts on telomere length in an Australian rural context. Additionally, it is unknown whether access to health services via the Australian public or private health system influences telomere length. AIM: This study investigates whether there is a relationship between telomere length and SES indicators (income, education) as well as health insurance status in a rural Australian population. METHODS: Samples were drawn from the Australian Rural Victoria cross-sectional Crossroads Study. Leucocyte telomere length (LTL) was measured using a multiplex quantitative polymerase chain reaction method. RESULTS: Among 1424 participants, we did not find a significant main effect association with LTL across education, income level and health insurance. An exploratory finding was sex may influence the relationship between educational attainment and LTL (P = 0.021). In males, but not females, higher education was associated with longer LTL by 0.033 [95% confidence interval (CI) 0.002-0.063, P = 0.035]; in those with low education attainment, male participants had shorter LTL by 0.058 (95% CI -0.086 to -0.029) than female participants (P < 0.0001). CONCLUSION: Being male and having lower education attainment was associated with shorter telomere length in our rural population. Evidence from our study supports the importance of education on LTL in males in rural Australia. Our studies also support previous findings that LTL in later life may not be closely associated with indicators of SES

    RUNX1T1 rs34269950 is associated with obesity and metabolic syndrome

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    Background: Runt-related transcription factor 1 (RUNX1T1) isoforms are involved in adipogenesis. RUNX1T1 is mediated by the fat mass and obesity-associated (FTO). However, the extent to which RUNX1T1 single nucleotide polymorphisms (SNPs), are associated with obesity risk or metabolic abnormalities in a community population basis is unknown. Methods: Samples were obtained from the Australian Crossroads study bio-bank. SNPs located in the coding region and 3’untranslated regions of RUNX1T1 with minor allele frequency (MAF) ≥ 0.05 were analysed using Taqman genotyping assays. Results: 8 candidate SNPs were genotyped successfully in 1440 participants. Of these SNPs only rs34269950 located in the “RRACH” motif, the most common N6-methyladenosine (m6A) methylation modification site (recognized by FTO), was significantly associated with obesity risk and metabolic abnormalities. Specifically, compared to AA genotype, rs34269950 del/del genotype was associated with a 1.47 (95% CI: 1.01-2.14, P = 0.042) fold higher rate of obesity risk. Additionally, the del/del genotype was associated with a 60% increased risk of metabolic syndrome (MetS) (OR = 1.60, 95% CI: 1.10 - 2.32, P = 0.015), in comparison to the AA genotype. Finally, rs34269950 del/del increased the risk of a larger waist circumference (OR = 1.65, 95% CI: 1.15 – 2.36, P = 0.007), but not other components of MetS. Conclusion: Our study demonstrates that RUNX1T1 rs34269950, located in a potential FTO recognition motif, is significantly associated with waist circumference. This provides novel evidence to suggest SNPs located in RRACH motif may be involved in RNA m6A modification and mechanistic pathways that influence abdominal obesity

    Myosin binding protein-C : enigmatic regulator of cardiac contraction

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    Myosin binding protein C (MyBPC) is a sarcomeric protein whose role in sarcomere structure and regulation of contraction is currently under investigation. It is a member of the immunoglobulin superfamily and is found in the C-zone of the A-band of the sarcomere. The elongated structure of MyBPC is composed of a series of immunoglobulin and fibronectin domains, with the C-terminal domains binding to the myosin thick filament and the N-terminal domains interacting with the myosin subfragment-2 (S2) neck region and possibly the actin thin filament. The functions of MyBPC are to stabilise the sarcomere structure and to regulate contraction. When phosphorylated near its N-terminus, MyBPC no longer binds myosin-S2, causing an increase in the ordering of the myosin heads, ATPase activity, Fmax and Ca²⁺ sensitivity of contraction. Mutations in MyBPC have been found to cause familial hypertrophic cardiomyopathy (FHC) and changes in MyBPC phosphorylation have been linked to cardiac ischaemia-reperfusion injury.6 page(s
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