Epigallocatechin-3-gallate remodels apolipoprotein A-I amyloid fibrils into soluble oligomers in the presence of heparin

Amyloid deposits of wild-type apolipoprotein A-I (apoA-I), the main protein component of high-density lipoprotein, accumulate in atherosclerotic plaques where they may contribute to coronary artery disease by increasing plaque burden and instability. Using CD analysis, solid-state NMR spectroscopy, and transmission EM, we report here a surprising cooperative effect of heparin and the green tea polyphenol (-)- epigallocatechin-3-gallate (EGCG), a known inhibitor and modulator of amyloid formation, on apoA-I fibrils. We found that heparin, a proxy for glycosaminoglycan (GAG) polysaccharides that co-localize ubiquitously with amyloid in vivo, accelerates the rate of apoA-I formation from monomeric protein and associates with insoluble fibrils. Mature, insoluble apoA-I fibrils bound EGCG (KD = 30 ± 3 μM; Bmax = 40 ± 3 μM), but EGCG did not alter the kinetics of apoA-I amyloid assembly from monomer in the presence or absence of heparin. EGCG selectively increased the mobility of specific backbone and side-chain sites of apoA-I fibrils formed in the absence of heparin, but the fibrils largely retained their original morphology and remained insoluble. By contrast, fibrils formed in the presence of heparin were mobilized extensively by the addition of equimolar EGCG, and the fibrils were remodeled into soluble 20-nm-diameter oligomers with a largely α-helical structure that were nontoxic to human umbilical artery endothelial cells. These results argue for a protective effect of EGCG on apoA-I amyloid associated with atherosclerosis and suggest that EGCG-induced remodeling of amyloid may be tightly regulated by GAGs and other amyloid co-factors in vivo, depending on EGCG bioavailability

Global network analysis in Schizosaccharomyces pombe reveals three distinct consequences of the common 1-kb deletion causing juvenile CLN3 disease

Juvenile CLN3 disease is a recessively inherited paediatric neurodegenerative disorder, with most patients homozygous for a 1-kb intragenic deletion in CLN3. The btn1 gene is the Schizosaccharomyces pombe orthologue of CLN3. Here, we have extended the use of synthetic genetic array (SGA) analyses to delineate functional signatures for two different disease-causing mutations in addition to complete deletion of btn1. We show that genetic-interaction signatures can differ for mutations in the same gene, which helps to dissect their distinct functional effects. The mutation equivalent to the minor transcript arising from the 1-kb deletion (btn1102–208del) shows a distinct interaction pattern. Taken together, our results imply that the minor 1-kb deletion transcript has three consequences for CLN3: to both lose and retain some inherent functions and to acquire abnormal characteristics. This has particular implications for the therapeutic development of juvenile CLN3 disease. In addition, this proof of concept could be applied to conserved genes for other mendelian disorders or any gene of interest, aiding in the dissection of their functional domains, unpacking the global consequences of disease pathogenesis, and clarifying genotype–phenotype correlations. In doing so, this detail will enhance the goals of personalised medicine to improve treatment outcomes and reduce adverse events

Orientation of a Diagnostic Ligand Bound to Macroscopically Aligned Amyloid-ß Fibrils Determined by Solid-state NMR

With amyloid diseases poised to become a major health burden in countries with aging populations, diagnostic molecules that aid the detection of amyloid in vitro and in vivo are of considerable clinical value. Understanding how such ligands recognize their amyloid targets would help to design diagnostics that target specific amyloid types associated with a particular disease, but methods to provide comprehensive information are underdeveloped. Here, solid-state NMR is used to determine the molecular orientation of the amyloid diagnostic 1-fluoro-2,5-bis[(E)-3-carboxy-4-hydroxystyryl]-benzene (FSB) when bound to fibrils of the Alzheimer’s amyloid-β polypeptide aligned on a planar substrate. The 19F NMR spectrum of the aligned complex reveals that FSB is oriented approximately parallel with the fibril long axis and bridges four hydrogen-bonded β-sheets. In addition to providing atomic details to aid the design of amyloid-specific diagnostics, this approach will also illuminate the molecular mechanisms of accessory molecules in amyloid disease

A Survey of Dog Owners in Remote Northern Australian Indigenous Communities to Inform Rabies Incursion Planning

Australia is underprepared for a rabies incursion due to a lack of information about how a rabies outbreak would spread within the susceptible canine populations and which control strategies would be best to control it. The aim of this study was to collect information to parameterize a recently developed dog rabies spread model as well as use this information to gauge how the community would accept potential control strategies. Such information–together with model outputs–would be used to inform decision makers on the best control strategies and improve Australia’s preparedness against a canine rabies incursion. The parameters this study focussed on were detection time, vaccination rates and dog-culling and dog movement restriction compliance. A cross-sectional survey of 31 dog-owners, using a questionnaire, was undertaken in the five communities of the Northern Peninsular Area (NPA) in northern Australia regarding community dog movements, veterinary visits, reporting systems, perceptions of sick dogs and potential human behaviours during hypothetical rabies outbreaks. It highlighted the significant shortfalls in veterinary care that would need to be vastly improved during an outbreak, who educational programs should be targeted towards and which dog movements should be restricted. The results indicate that men were significantly more likely than women to allow their dogs to roam and to move their dogs. The current low vaccination rate of 12% highlighted the limited veterinary services that would need to be substantially increased to achieve effective rabies control. Participation in mass vaccination was accepted by 100% of the respondents. There was lower acceptance for other possible rabies control strategies with 10–20% of the respondents stating a resistance to both a mass culling program and a ban on dog movements. Consequently, movement bans and mass dog culling would have limited effectiveness as a control strategy in the NPA community. More than half of the respondents said that they would report their sick dogs within a week. This would lead to a much more optimistic rabies detection time than observed in other regions with recent dog rabies outbreaks. Findings from this study can be used to parameterize a recently developed dog rabies spread model as well as to develop informed policies for managing a future rabies incursion, thus improving Australia’s preparedness against a canine rabies incursion. Author Summary Australia is underprepared for a rabies incursion due to limited information about how a rabies outbreak would behave and which control strategies would be best to control it. A disease spread model of rabies has been developed to help policy-makers decide on the best response to a rabies incursion. However, data to inform this model are lacking. Therefore, the aim of this study was to gather information to parameterize the existing rabies spread model and to gauge how the community would accept potential control strategies. A survey of dog-owners, using a questionnaire, was undertaken in five remote, indigenous communities in northern Australia. We found that compared to women, men were more likely to allow their dogs to roam and to move their dogs. The current vaccination rates in these dog populations are low due to limited veterinary services. This would make delivery of vaccine in the event of a rabies incursion potentially challenging. However, compliance of dog owners with mass vaccination campaigns would be high. However, compliance with movement control of dogs might be problematic, as would the mass culling of dogs, although, rabies detection following an incursion could optimistically occur within a week

Designing programs for eliminating canine rabies from islands: Bali, Indonesia as a case study

<p>Background: Canine rabies is one of the most important and feared zoonotic diseases in the world. In some regions rabies elimination is being successfully coordinated, whereas in others rabies is endemic and continues to spread to uninfected areas. As epidemics emerge, both accepted and contentious control methods are used, as questions remain over the most effective strategy to eliminate rabies. The Indonesian island of Bali was rabies-free until 2008 when an epidemic in domestic dogs began, resulting in the deaths of over 100 people. Here we analyze data from the epidemic and compare the effectiveness of control methods at eliminating rabies.</p> <p>Methodology/Principal Findings: Using data from Bali, we estimated the basic reproductive number, R0, of rabies in dogs, to be ~1·2, almost identical to that obtained in ten–fold less dense dog populations and suggesting rabies will not be effectively controlled by reducing dog density. We then developed a model to compare options for mass dog vaccination. Comprehensive high coverage was the single most important factor for achieving elimination, with omission of even small areas (<0.5% of the dog population) jeopardizing success. Parameterizing the model with data from the 2010 and 2011 vaccination campaigns, we show that a comprehensive high coverage campaign in 2012 would likely result in elimination, saving ~550 human lives and ~$15 million in prophylaxis costs over the next ten years.</p> <p>Conclusions/Significance: The elimination of rabies from Bali will not be achieved through achievable reductions in dog density. To ensure elimination, concerted high coverage, repeated, mass dog vaccination campaigns are necessary and the cooperation of all regions of the island is critical. Momentum is building towards development of a strategy for the global elimination of canine rabies, and this study offers valuable new insights about the dynamics and control of this disease, with immediate practical relevance.</p&gt

A systematic review investigating fatigue, psychological and cognitive impairment following TIA and minor stroke:protocol paper

Approximately 20,000 people have a transient ischemic attack (TIA) and 23,375 have a minor stroke in England each year. Fatigue, psychological and cognitive impairments are well documented post-stroke. Evidence suggests that TIA and minor stroke patients also experience these impairments; however, they are not routinely offered relevant treatment. This systematic review aims to: (1) establish the prevalence of fatigue, anxiety, depression, post-traumatic stress disorder (PTSD) and cognitive impairment following TIA and minor stroke and to investigate the temporal course of these impairments; (2) explore impact on quality of life (QoL), change in emotions and return to work; (3) identify where further research is required and to potentially inform an intervention study

Endangered right whales enhance primary productivity in the bay of fundy

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. Marine mammals have recently been documented as important facilitators of rapid and efficient nutrient recycling in coastal and offshore waters. Whales enhance phytoplankton nutrition by releasing fecal plumes near the surface after feeding and by migrating from highly productive, high-latitude feeding areas to low-latitude nutrient-poor calving areas. In this study, we measured NH4 + and PO4 3- release rates from the feces of North Atlantic right whales (Eubalaena glacialis), a highly endangered baleen whale. Samples for this species were primarily collected by locating aggregations of whales in surface- Active groups (SAGs), which typically consist of a central female surrounded by males competing for sexual activity. When freshly collected feces were incubated in seawater, high initial rates of N release were generally observed, which decreased to near zero within 24 hours of sampling, a pattern that is consistent with the active role of gut microflora on fecal particles. We estimate that at least 10% of particulate N in whale feces becomes available as NH4 + within 24 hours of defecation. Phosphorous was also abundant in fecal samples: Initial release rates of PO4 3- were higher than for NH4 +, yielding low N/P nutrient ratios over the course of our experiments. The rate of PO4 3- release was thus more than sufficient to preclude the possibility that nitrogenous nutrients supplied by whales would lead to phytoplankton production limited by P availability. Phytoplankton growth experiments indicated that NH4 + released from whale feces enhance productivity, as would be expected, with no evidence that fecal metabolites suppress growth. Although North Atlantic right whales are currently rare (approximately 450 individuals), they once numbered about 14,000 and likely played a substantial role in recycling nutrients in areas where they gathered to feed and mate. Even though the NH4 + released from fresh whale fecal material is a small fraction of total whale fecal nitrogen, and recognizing the fact that the additional nitrogen released in whale urine would be difficult to measure in a field study, the results of this study support the idea that the distinctive isotopic signature of the released NH4 + could be used to provide a conservative estimate of the contribution of the whale pump to primary productivity in coastal regions where whales congregate

Estimation of the prevalence of cholesteryl ester storage disorder in a cohort of patients with clinical features of familial hypercholesterolaemia

Background and aim Familial hypercholesterolaemia is caused by variants in the low-density lipoprotein cholesterol metabolic pathway involving LDLR, APOB and PCSK9 genes. A national genetic testing service in Wales, UK has observed that no familial hypercholesterolaemia variant is found in almost 80% patients with the familial hypercholesterolaemia phenotype. It has recently been suggested that some adult patients with a familial hypercholesterolaemia phenotype may have cholesteryl ester storage disease which can also present as a mixed hyperlipidaemia. The commonest genetic cause of cholesteryl ester storage disease is an exon 8 splice junction variant in the LIPA gene (rs116928232, c.894G>A; E8SJM) previously found to have an allele frequency of 0.0011 (1 in 450 individuals) in a large European population. This study investigated the prevalence of the E8SJM in patients with a familial hypercholesterolaemia phenotype in Wales, UK. Method A total of 1203 patients with a clinical suspicion of familial hypercholesterolaemia but no familial hypercholesterolaemia variant were invited to participate. Of these, 668 patients provided informed written consent. Stored DNA samples from 663 patients were genotyped for the E8SJM variant. Results Three heterozygotes were identified (allele frequency 0.0023). Whole gene sequencing of the LIPA gene was undertaken in these three individuals, but no other variants were found. Therefore, there were no cholesteryl ester storage disease patients (homozygote or compound heterozygote) identified in this cohort. Conclusion The allele frequency 0.0023 (1 in 221 individuals) for the E8SJM variant was more prevalent in this cohort than in a European population study; however, no cholesteryl ester storage disease homozygotes were identified. We found no evidence to support routine testing for cholesteryl ester storage disease in adult patients with a familial hypercholesterolaemia phenotype