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Necroptosis is a mode of programmed, lytic cell death that is executed by the mixed lineage kinase domain-like (MLKL) pseudokinase following activation by the upstream kinases, receptor-interacting serine/threonine protein kinase (RIPK)-1 and RIPK3. Dysregulated necroptosis has been implicated in the pathophysiology of many human diseases, including inflammatory and degenerative conditions, infectious diseases and cancers, provoking interest in pharmacological targeting of the pathway. To identify small molecules impacting on the necroptotic machinery, we performed a phenotypic screen using a mouse cell line expressing an MLKL mutant that kills cells in the absence of upstream death or pathogen detector receptor activation. This screen identified the vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR) tyrosine kinase inhibitor, ABT-869 (Linifanib), as a small molecule inhibitor of necroptosis. We applied a suite of cellular, biochemical and biophysical analyses to pinpoint the apical necroptotic kinase, RIPK1, as the target of ABT-869 inhibition. Our study adds to the repertoire of established protein kinase inhibitors that additionally target RIPK1 and raises the prospect that serendipitous targeting of necroptosis signalling may contribute to their clinical efficacy in some settings.

Ebola virus (EBOV) causes lethal disease in humans but not in mice. Here, we generated recombinant mouse-adapted (MA)-EBOVs, including one based on the previously reported serially adapted strain (rMA-EBOV), along with single-reporter rMA-EBOVs expressing either fluorescent (ZsGreen1 [ZsG]) or bioluminescent (nano-luciferase [nLuc]) reporters, and dual-reporter rMA-EBOVs expressing both ZsG and nLuc. No detriment to viral growth in vitro was seen with inclusion of MA-associated mutations or reporter proteins. In CD-1 mice, infection with MA-EBOV, rMA-EBOV, and single-reporter rMA-EBOVs conferred 100% lethality; infection with dual-reporter rMA-EBOV resulted in 80% lethality. Bioluminescent signal from rMA-EBOV expressing nLuc was detected in vivo and ex vivo using the IVIS Spectrum CT. Fluorescent signal from rMA-EBOV expressing ZsG was detected in situ using hand-held blue-light transillumination and ex vivo through epi-illumination with the IVIS Spectrum CT. These data support the use of reporter MA-EBOV for studies of Ebola virus in animal disease models.

Development of lethal models of Ebola virus disease has been achieved by the serial passage of virus isolates from human cases in mice and guinea pigs. Use of mice infected with non-adapted virus has been limited due to the absence of overt clinical disease. In recent years, newly recognized sequelae identified in human cases has highlighted the importance of continued investigations of non-lethal infection both in humans and animal models. Here, we revisit the use of rodent-adapted and non-adapted Ebola virus (EBOV) variants in mice to investigate infection tolerance and future utility of these models in pathogenesis and therapeutic intervention studies. We found that like non-adapted wild-type EBOV, guinea pig-adapted EBOV results in widespread tissue infection, variably associated with tissue pathology, and alterations in clinical and immunological analytes in the absence of overt disease. Notably, infection with either non-lethal variant does not greatly differ from lethal mouse-adapted EBOV until near the time end-point criteria are reached in these mice, supporting use of these models of virus tolerance for continued investigations of non-lethal infection and sequelae.

Analytical chemistry 93(32), 11108 - 11115 (2021). doi:10.1021/acs.analchem.1c01128, Studies of the metal content of metalloproteins in tissues from the human central nervous system (CNS) can be compromised by preparative techniques which alter levels of, or interactions between, metals and the protein of interest within a complex mixture. We developed a methodological workflow combining size exclusion chromatography, native isoelectric focusing, and either proton or synchrotron X-ray fluorescence within electrophoresis gels to analyze the endogenous metal content of copper-zinc superoxide dismutase (SOD1) purified from minimal amounts (, Published by American Chemical Society, Columbus, Ohio

Recent work on Pitman closeness has compared estimators under Type-II censored samples from an exponential distribution. More recently, a comparison was done for Type-I censored data wherein two es...

Mixed lineage kinase domain-like (MLKL) is the terminal protein in the pro-inflammatory necroptotic cell death program. RIPK3-mediated phosphorylation is thought to initiate MLKL oligomerization, membrane translocation and membrane disruption, although the precise choreography of events is incompletely understood. Here, we use single-cell imaging approaches to map the chronology of endogenous human MLKL activation during necroptosis. During the effector phase of necroptosis, we observe that phosphorylated MLKL assembles into higher order species on presumed cytoplasmic necrosomes. Subsequently, MLKL co-traffics with tight junction proteins to the cell periphery via Golgi-microtubule-actin-dependent mechanisms. MLKL and tight junction proteins then steadily co-accumulate at the plasma membrane as heterogeneous micron-sized hotspots. Our studies identify MLKL trafficking and plasma membrane accumulation as crucial necroptosis checkpoints. Furthermore, the accumulation of phosphorylated MLKL at intercellular junctions accelerates necroptosis between neighbouring cells, which may be relevant to inflammatory bowel disease and other necroptosis-mediated enteropathies., Mixed lineage kinase domain-like (MLKL) is the terminal protein in the pro-inflammatory necroptotic cell death program. Here the authors show that MLKL trafficking and plasma membrane accumulation are crucial necroptosis checkpoints, and that accumulation of phosphorylated MLKL at intercellular junctions promotes necroptosis.

Across different types of lifetime studies, whether it be in the medical or engineering sciences, the possibility of competing causes of failures needs to be addressed. Typically referred to as com...

The necroptosis cell death pathway has been implicated in host defense and in the pathology of inflammatory diseases. While phosphorylation of the necroptotic effector pseudokinase Mixed Lineage Kinase Domain-Like (MLKL) by the upstream protein kinase RIPK3 is a hallmark of pathway activation, the precise checkpoints in necroptosis signaling are still unclear. Here we have developed monobodies, synthetic binding proteins, that bind the N-terminal four-helix bundle (4HB) “killer” domain and neighboring first brace helix of human MLKL with nanomolar affinity. When expressed as genetically encoded reagents in cells, these monobodies potently block necroptotic cell death. However, they did not prevent MLKL recruitment to the “necrosome” and phosphorylation by RIPK3, nor the assembly of MLKL into oligomers, but did block MLKL translocation to membranes where activated MLKL normally disrupts membranes to kill cells. An X-ray crystal structure revealed a monobody-binding site centered on the α4 helix of the MLKL 4HB domain, which mutational analyses showed was crucial for reconstitution of necroptosis signaling. These data implicate the α4 helix of its 4HB domain as a crucial site for recruitment of adaptor proteins that mediate membrane translocation, distinct from known phospholipid binding sites.

The ancestral origins of the lytic cell death mode, necroptosis, lie in host defense. However, the dysregulation of necroptosis in inflammatory diseases has led to widespread interest in targeting the pathway therapeutically. This mode of cell death is executed by the terminal effector, the MLKL pseudokinase, which is licensed to kill following phosphorylation by its upstream regulator, RIPK3 kinase. The precise molecular details underlying MLKL activation are still emerging and, intriguingly, appear to mechanistically-diverge between species. Here, we report the structure of the human RIPK3 kinase domain alone and in complex with the MLKL pseudokinase. These structures reveal how human RIPK3 structurally differs from its mouse counterpart, and how human RIPK3 maintains MLKL in an inactive conformation prior to induction of necroptosis. Residues within the RIPK3:MLKL C-lobe interface are crucial to complex assembly and necroptotic signaling in human cells, thereby rationalizing the strict species specificity governing RIPK3 activation of MLKL., The pseudokinase MLKL is activated by the upstream kinase RIPK3 in the necroptotic pathway but the structural basis of MLKL activation is not well understood yet. Here, the authors present the crystal structures of the human RIPK3:MLKL complex and human RIPK3 kinase alone, which reveal structural differences between human and murine RIPK3 and they discuss mechanistic implications.

Necroptosis is a lytic programmed cell death pathway with origins in innate immunity that is frequently dysregulated in inflammatory diseases. The terminal effector of the pathway, MLKL, is licensed to kill following phosphorylation of its pseudokinase domain by the upstream regulator, RIPK3 kinase. Phosphorylation provokes the unleashing of MLKL’s N-terminal four-helix bundle (4HB or HeLo) domain, which binds and permeabilizes the plasma membrane to cause cell death. The precise mechanism by which the 4HB domain permeabilizes membranes, and how the mechanism differs between species, remains unclear. Here, we identify the membrane binding epitope of mouse MLKL using NMR spectroscopy. Using liposome permeabilization and cell death assays, we validate K69 in the α3 helix, W108 in the α4 helix, and R137/Q138 in the first brace helix as crucial residues for necroptotic signaling. This epitope differs from the phospholipid binding site reported for human MLKL, which comprises basic residues primarily located in the α1 and α2 helices. In further contrast to human and plant MLKL orthologs, in which the α3-α4 loop forms a helix, this loop is unstructured in mouse MLKL in solution. Together, these findings illustrate the versatility of the 4HB domain fold, whose lytic function can be mediated by distinct epitopes in different orthologs.

Necroptosis is a lytic programmed cell death pathway with origins in innate immunity that is frequently dysregulated in inflammatory diseases. The terminal effector of the pathway, MLKL, is licensed to kill following phosphorylation of its pseudokinase domain by the upstream regulator, RIPK3 kinase. Phosphorylation provokes the unleashing of MLKL's N-terminal four-helix bundle (4HB or HeLo) domain, which binds and permeabilizes the plasma membrane to cause cell death. The precise mechanism by which the 4HB domain permeabilizes membranes, and how the mechanism differs between species, remains unclear. Here, we identify the membrane binding epitope of mouse MLKL using NMR spectroscopy. Using liposome permeabilization and cell death assays, we validate K69 in the α3 helix, W108 in the α4 helix, and R137/Q138 in the first brace helix as crucial residues for necroptotic signaling. This epitope differs from the phospholipid binding site reported for human MLKL, which comprises basic residues primarily located in the α1 and α2 helices. In further contrast to human and plant MLKL orthologs, in which the α3-α4 loop forms a helix, this loop is unstructured in mouse MLKL in solution. Together, these findings illustrate the versatility of the 4HB domain fold, whose lytic function can be mediated by distinct epitopes in different orthologs.

The excessive use of antimicrobial agents such as antibiotics and disinfectants for domestic purposes and industries polluted the water bodies severely in the recent past. Thus released antimicrobial agents negatively impact the environment and human health as it induce antimicrobial resistance (AMR) to microbes in the environment. Conventional biodegradation routes showed feasible antibiotics pollutants degradation. Nonetheless, they often demand a long time of operation (usually in days) and a major portion of the antimicrobial agents is left untreated unlike the complete oxidation with advanced oxidation processes. The residues of antibiotics left in the water bodies accelerate growth of microorganisms (bacterial, fungal, and viral) with AMR. In virtue of avoiding the catastrophe of widespread AMR, photocatalysis assisted antibiotic pollutant treatment is recently gaining a great popularity as an advanced oxidation process and has shown to be useful for the removal of antimicrobial compounds, mainly antibiotics. Recent review reports on photocatalytic antibiotic degradation focus on summarizing materials progress and antibiotics pollutants in chronological viewpoints. However, the relationship between photocatalytic materials and antibiotics oxidation reaction pathways and the toxicity of by-products are needed to be shown with better clarity to transfer the photocatalysis technique from lab to market in a safe way. This review critically analyzes the insights of energetic semiconductor structure lacking to achieve hydroxyl and superoxide radicals mediated antibiotics degradation, recommends new materials design (Z scheme) and standardization in the experimental designs, and also informs the influencing parameters on antibiotic degradation. It further assesses the possibility of recovering value-added chemicals from the photocatalytic treatment process and highlights the importance of environmental toxicity analysis. Overall, this review will be a resourceful guide for interdisciplinary researchers working on advanced photocatalysis and pharmaceutical pollutant treatment for achieving a sustainable ecology and initiating a circular economy in chemical industries.

Power-free, light-driven catalysis-based water treatment is a green approach compared to chemical-based water treatment techniques. In this context, a broad range of photocatalytic material is demonstrated for organic water pollutant treatment. However, understanding catalysis reaction at pollutant environment and by-product formation are ambiguous. In this view, this chapter discusses insights of photocatalysis in organic water pollutant treatment at different pollutants (textile dye, pharmaceutical drug and pesticide) using TiO2 as benchmarking photocatalyst. The analytical tools for evaluating the light-active and colourless pollutant before and after photocatalytic experiments are elaborately discussed. A comprehensive discussion on TiO2-based photocatalysis at different strategies such as metal doping, coated on host surface, and varying pH of the solution are clearly explaining the interrelationship between properties of semiconductor catalysts, processing parameters and photocatalytic performance. This chapter is resourceful for fundamental researchers on how to choose the photocatalysis experimental techniques for organic water pollutant treatment.

The feasibility of a solar-driven photoelectrochemical process to generate hydrogen fuel from metal mine polluted water while simultaneously recovering heavy metals has been explored. Electron transport from the photoanode to the cathode plays a key role in generating hydrogen (37.6 μmol h−1 cm−2 at 0.2 V RHE, 1 sun illumination), and scavenging Zn2+ ions in the form of ZnO.

BACKGROUND: Excessive sweating of the residual limb has a substantial effect on the daily activities of people with lower limb amputation. Prosthetic liners offer protection and comfort to sensitive areas but often exacerbate perspiration. They act as insulators, trapping sweat on the skin’s surface to the detriment of skin health. Recently, liners with perforations have been developed, allowing the moisture to escape. The goal of this study was to assess the impact of such liners. METHODS: A sample group of 13 patients with unilateral transtibial amputation, who wore a perforated liner (PL) as part of their current prescription, was compared to 20 control patients who wore non-perforated liners (NPL). During their routine appointments, they completed a survey of scientifically validated outcome measures relating to their limb health, pain and the impact on daily life over a 12-month period. RESULTS: Patients using the PL had healthier residual limbs, reporting higher scores on questions relating to limb health, experiencing fewer skin issues (p

The family Hantaviridae within the Bunyavirales order comprises tri-segmented negative sense RNA viruses, many of which are rodent-borne emerging pathogens associated with fatal human disease. In contrast, hantavirus infection of corresponding rodent hosts results in inapparent or latent infections, which can be recapitulated in cultured cells that become persistently infected. In this study, we used Tula virus (TULV) to investigate the location of hantavirus replication during early, peak and persistent phases of infection, over a 30-day time course. Using immunofluorescent (IF) microscopy, we showed that the TULV nucleocapsid protein (NP) is distributed within both punctate and filamentous structures, with the latter increasing in size as the infection progresses. Transmission electron microscopy of TULV-infected cell sections revealed these filamentous structures comprised aligned clusters of filament bundles. The filamentous NP-associated structures increasingly co-localized with the Golgi and with the stress granule marker TIA-1 over the infection time course, suggesting a redistribution of these cellular organelles. The analysis of the intracellular distribution of TULV RNAs using fluorescent in-situ hybridization revealed that both genomic and mRNAs co-localized with Golgi-associated filamentous compartments that were positive for TIA. These results show that TULV induces a dramatic reorganization of the intracellular environment, including the establishment of TULV RNA synthesis factories in re-modelled Golgi compartments.

The MLKL pseudokinase is the terminal effector in the necroptosis cell death pathway. Phosphorylation by its upstream regulator, RIPK3, triggers MLKL’s conversion from a dormant cytoplasmic protein into oligomers that translocate to, and permeabilize, the plasma membrane to kill cells. The precise mechanisms underlying these processes are incompletely understood, and were proposed to differ between mouse and human cells. Here, we examine the divergence of activation mechanisms among nine vertebrate MLKL orthologues, revealing remarkable specificity of mouse and human RIPK3 for MLKL orthologues. Pig MLKL can restore necroptotic signaling in human cells; while horse and pig, but not rat, MLKL can reconstitute the mouse pathway. This selectivity can be rationalized from the distinct conformations observed in the crystal structures of horse and rat MLKL pseudokinase domains. These studies identify important differences in necroptotic signaling between species, and suggest that, more broadly, divergent regulatory mechanisms may exist among orthologous pseudoenzymes., The necroptotic cell death pathway involves signaling through pseudokinases. Here the authors define the structural determinants of species specificity in necroptosis signaling mediated by the essential necroptotic effector pseudokinase, Mixed Lineage Kinase Domain-Like (MLKL).

BACKGROUND: Lower limb amputees have a high incidence of comorbidities, such as osteoarthritis, which are believed to be caused by kinetic asymmetries. A lack of prosthetic adaptation to different terrains requires kinematic compensations, which may influence these asymmetries. METHOD: Six SIGAM grade E-F trans-tibial amputees (one bilateral) wore motion capture markers while standing on force plates, facing down a 5° slope. The participants were tested under three prosthetic conditions; a fixed attachment foot (FIX), a hydraulic ankle (HYD) and a microprocessor foot with a ‘standing support’ mode (MPF). The resultant ground reaction force (GRF) and support moment for prosthetic and sound limbs were chosen as outcome measures. These were compared between prosthetic conditions and to previously captured able-bodied control data. RESULTS: The distribution of GRF between sound and prosthetic limbs was not significantly affected by foot type. However, the MPF condition required fewer kinematic compensations, leading to a reduction in sound side support moment of 59% (p=0.001) and prosthetic side support moment of 43% (p=0.02) compared to FIX. For the bilateral participant, only the MPF positioned the GRF vector anterior to the knees, reducing the demand on the residual joints to maintain posture. CONCLUSION: For trans-tibial amputees, loading on lower limb joints is affected by prosthetic foot technology, due to the kinematic compensations required for slope adaptation. MPFs with ‘standing support’ might be considered reasonable and necessary for bilateral amputees, or amputees with stability problems due to the reduced biomechanical compensations evident. LAYMAN’S ABSTRACT: Lower limb prostheses work well on flat ground but often don’t adapt well to uneven ground or slopes. As a result, amputees tend to put more of their weight through their healthy leg. This can lead to problems like back pain and arthritis. In this study, the posture and weight distribution of below knee amputees were analysed while they stood facing down a slope. They did this with three different prosthetic feet; one with no ‘ankle’ joint, one with an ‘ankle’ (which could always move) and one with a computer-controlled ‘ankle’ (which could adapt to the slope but then resist movement when the wearer was stood still). Changing the prosthetic feet did not affect the amount of weight put through each limb, but when they had ‘ankle’ joints, the amputees were able to stand up straight, with a better posture. This meant that the demand on their joints was reduced, particularly on the healthy limb. One participant had below knee amputations on both legs. For this participant, only the computer-controlled device allowed her to stand up straight and well balanced. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/33517/25933 How to Cite: McGrath M, Davies KC, Laszczak P, Rek B, McCarthy J, Zahedi S, Moser D. The influence of hydraulic ankles and microprocessor-control on the biomechanics of trans-tibial amputees during quiet standing on a 5° slope. Canadian Prosthetics & Orthotics Journal. 2019;Volume2, Issue2, No.2. https://doi.org/10.33137/cpoj.v2i2.33517 CORRESPONDING AUTHOR Dr. Michael McGrath,Research Scientist–Clinical EvidenceBlatchford Group, Unit D Antura, Bond Close, Basingstoke, RG24 8PZ, United KingdomEmail: mike.mcgrath@blatchford.co.ukORCID: https://orcid.org/0000-0003-0195-970X

In this paper, we consider two well-known parametric long-term survival models, namely, the Bernoulli cure rate model and the promotion time (or Poisson) cure rate model. Assuming the long-term survival probability to depend on a set of risk factors, the main contribution is in the development of the stochastic expectation maximization (SEM) algorithm to determine the maximum likelihood estimates of the model parameters. We carry out a detailed simulation study to demonstrate the performance of the proposed SEM algorithm. For this purpose, we assume the lifetimes due to each competing cause to follow a two-parameter generalized exponential distribution. We also compare the results obtained from the SEM algorithm with those obtained from the well-known expectation maximization (EM) algorithm. Furthermore, we investigate a simplified estimation procedure for both SEM and EM algorithms that allow the objective function to be maximized to split into simpler functions with lower dimensions with respect to model parameters. Moreover, we present examples where the EM algorithm fails to converge but the SEM algorithm still works. For illustrative purposes, we analyze a breast cancer survival data. Finally, we use a graphical method to assess the goodness-of-fit of the model with generalized exponential lifetimes.

The programmed cell death pathway, necroptosis, relies on the pseudokinase, Mixed Lineage Kinase domain-Like (MLKL), for cellular execution downstream of death receptor or Toll-like receptor ligation. Receptor-interacting protein kinase-3 (RIPK3)-mediated phosphorylation of MLKL’s pseudokinase domain leads to MLKL switching from an inert to activated state, where exposure of the N-terminal four-helix bundle (4HB) ‘executioner’ domain leads to cell death. The precise molecular details of MLKL activation, including the stoichiometry of oligomer assemblies, mechanisms of membrane translocation and permeabilisation, remain a matter of debate. Here, we dissect the function of the two ‘brace’ helices that connect the 4HB to the pseudokinase domain of MLKL. In addition to establishing that the integrity of the second brace helix is crucial for the assembly of mouse MLKL homotrimers and cell death, we implicate the brace helices as a device to communicate pseudokinase domain phosphorylation event(s) to the N-terminal executioner 4HB domain. Using mouse:human MLKL chimeras, we defined the first brace helix and adjacent loop as key elements of the molecular switch mechanism that relay pseudokinase domain phosphorylation to the activation of the 4HB domain killing activity. In addition, our chimera data revealed the importance of the pseudokinase domain in conferring host specificity on MLKL killing function, where fusion of the mouse pseudokinase domain converted the human 4HB + brace from inactive to a constitutive killer of mouse fibroblasts. These findings illustrate that the brace helices play an active role in MLKL regulation, rather than simply acting as a tether between the 4HB and pseudokinase domains.

In life-testing and reliability studies, it is commonly assumed that the lifetimes come from a continuous distribution. While this often makes derivations more tractable, under certain circumstances, it may be more realistic to assume a discrete distribution. Recent literature has heavily focused on the former and with this, results have been aimed at deriving properties in the case of independent and identically distributed random variables and associated order statistics. In this paper, we consider the case of discrete order statistics from non-identical distributions. We derive expression for single and product moments, and with this, covariances. We demonstrate the results for the geometric and binomial distributions.

The family Hantaviridae mostly comprises rodent-borne segmented negative-sense RNA viruses, many of which are capable of causing devastating disease in humans. In contrast, hantavirus infection of rodent hosts results in a persistent and inapparent infection through their ability to evade immune detection and inhibit apoptosis. In this study, we used Tula hantavirus (TULV) to investigate the interplay between viral and host apoptotic responses during early, peak and persistent phases of virus infection in cell culture. Examination of early-phase TULV infection revealed that infected cells were refractory to apoptosis, as evidenced by the complete lack of cleaved caspase-3 (casp-3C) staining, whereas in non-infected bystander cells casp-3C was highly abundant. Interestingly, at later time points, casp-3C was abundant in infected cells, but the cells remained viable and able to continue shedding infectious virus, and together these observations were suggestive of a TULV-associated apoptotic block. To investigate this block, we viewed TULV-infected cells using laser scanning confocal and wide-field deconvolution microscopy, which revealed that TULV nucleocapsid protein (NP) colocalized with, and sequestered, casp-3C within cytoplasmic ultrastructures. Consistent with casp-3C colocalization, we showed for the first time that TULV NP was cleaved in cells and that TULV NP and casp-3C could be co-immunoprecipitated, suggesting that this interaction was stable and thus unlikely to be solely confined to NP binding as a substrate to the casp-3C active site. To account for these findings, we propose a novel mechanism by which TULV NP inhibits apoptosis by spatially sequestering casp-3C from its downstream apoptotic targets within the cytosol.

In this paper, a mixture representation is derived for the pooled system lifetimes arising from a life-test on two or more independent samples. The components of each system are assumed to have the same common absolutely continuous distribution, but the system signature may vary between the samples. These mixtures are then used for developing exact nonparametric inference in the form of confidence intervals for quantiles of component or system lifetimes, as well as prediction intervals for future component or system lifetimes. Examples are finally provided to illustrate the developed methods. It is noted that testing with systems rather than components directly can reduce the expected number of failures while maintaining nominal coverage probability.

Copper is a biometal essential for normal brain development and function, thus copper deficiency or excess results in central nervous system disease. Well-characterized disorders of disrupted copper homoeostasis with neuronal degeneration include Menkes disease and Wilson's disease but a large body of evidence also implicates disrupted copper pathways in other neurodegenerative disorders, including Parkinson's disease, Alzheimer's disease, Amyotrophic lateral sclerosis, Huntington's disease and prion diseases. In this short review we critically evaluate the data regarding changes in systemic and brain copper levels in Parkinson's disease, where alterations in brain copper are associated with regional neuronal cell death and disease pathology. We review copper regulating mechanisms in the human brain and the effects of dysfunction within these systems. We then examine the evidence for a role for copper in pathogenic processes in Parkinson's disease and consider reports of diverse copper-modulating strategies in in vitro and in vivo models of this disorder. Copper-modulating therapies are currently advancing through clinical trials for Alzheimer's and Huntington's disease and may also hold promise as disease modifying agents in Parkinson's disease.

Rural coastal communities in the global south are mostly natural resource-dependent and their livelihoods are therefore vulnerable to the impacts of climate and environmental changes. Efforts to improve their adaptive capacity often prove mal-adaptive due to misunderstanding the dynamics of the unique socioeconomic factors that shape their vulnerability. By integrating theories from climate change vulnerability and the Sustainable Livelihoods Approach, this study draws upon household survey data from a fishing community in Ghana to assess the vulnerability of fishing households to climate change and explore how their vulnerability is differentiated within the community. The findings suggest that household incomes in the last decade have reduced significantly, attributable to an interaction of both climatic and non-climatic factors. Analysis of the characteristics of three vulnerability groups derived by quantile clustering showed that the most vulnerable household group is not necessarily women or poorer households as expected. Rather, it is dynamic and includes all gender and economic class categories in varying proportions depending on the success or failure of the fishing season. The findings suggest furthermore that the factors that significantly differentiates vulnerability between households differ, depending on whether households are categorised by economic class, gender of household-head or vulnerability group. Consequently, the study highlights the importance of looking beyond existing social categorizations like gender and economic classes when identifying and prioritizing households for climate change adaptive capacity building.

In this paper we consider correlation-type tests based on plotting points which are modifications to the simultaneous closeness probability plotting points as recently introduced in the literature. In particular, we consider a maximal correlation test and a minimal correlation test. Furthermore, we provide two methods to carry out each test, where one method uses plotting points which are data dependent and the other test uses plotting points which are not. Some numerical properties on the associated correlation statistics are provided for various distributions, as well as a comprehensive power study to assess their performance in comparison to correlation-type tests based on more traditional plotting points. Two illustrative examples are also provided to demonstrate the tests. Finally, we make some observations and provide ideas for future work.

© 2017, Springer-Verlag Berlin Heidelberg. Neuronal loss in numerous neurodegenerative disorders has been linked to protein aggregation and oxidative stress. Emerging data regarding overlapping proteinopathy in traditionally distinct neurodegenerative diseases suggest that disease-modifying treatments targeting these pathological features may exhibit efficacy across multiple disorders. Here, we describe proteinopathy distinct from classic synucleinopathy, predominantly comprised of the anti-oxidant enzyme superoxide dismutase-1 (SOD1), in the Parkinson’s disease brain. Significant expression of this pathology closely reflected the regional pattern of neuronal loss. The protein composition and non-amyloid macrostructure of these novel aggregates closely resembles that of neurotoxic SOD1 deposits in SOD1-associated familial amyotrophic lateral sclerosis (fALS). Consistent with the hypothesis that deposition of protein aggregates in neurodegenerative disorders reflects upstream dysfunction, we demonstrated that SOD1 in the Parkinson’s disease brain exhibits evidence of misfolding and metal deficiency, similar to that seen in mutant SOD1 in fALS. Our data suggest common mechanisms of toxic SOD1 aggregation in both disorders and a potential role for SOD1 dysfunction in neuronal loss in the Parkinson’s disease brain. This shared restricted proteinopathy highlights the potential translation of therapeutic approaches targeting SOD1 toxicity, already in clinical trials for ALS, into disease-modifying treatments for Parkinson’s disease.

In this paper, we consider two problems concerning two independent progressively Type-II censored samples. We first consider the Pitman closeness (PC) of order statistics from two independent progressively censored samples to a specific population quantile. We then consider the point prediction of a future progressively censored order statistic and discuss the determination of the closest progressively censored order statistic from the current sample according to the simultaneous closeness probabilities. For both these problems, explicit expressions are derived for the pertinent PC probabilities, and then special cases are given as examples. For various censoring schemes, we also present numerical results for the standard uniform, standard exponential, and standard normal distributions. Finally, a distribution-free result for the median is obtained.

Recent work on Pitman closeness has compared estimators under Type-II censored samples from exponential distribution based on observed number of failures. In this paper, we carry out similar Pitman closeness comparisons for Type-I censored samples from exponential distribution based on time under test.

In this paper, we focus on Pitman closeness probabilities when the estimators are symmetrically distributed about the unknown parameter θ. We first consider two symmetric estimators θˆ1 and θˆ2 and obtain necessary and sufficient conditions for θˆ1 to be Pitman closer to the common median θ than θˆ2. We then establish some properties in the context of estimation under the Pitman closeness criterion. We define Pitman closeness probability which measures the frequency with which an individual order statistic is Pitman closer to θ than some symmetric estimator. We show that, for symmetric populations, the sample median is Pitman closer to the population median than any other independent and symmetrically distributed estimator of θ. Finally, we discuss the use of Pitman closeness probabilities in the determination of an optimal ranked set sampling scheme (denoted by RSS) for the estimation of the population median when the underlying distribution is symmetric. We show that the best RSS scheme from symmetric p...

In this work, we extend prior results concerning the simultaneous Pitman closeness of order statistics (OS) to population quantiles. By considering progressively type-II right-censored samples, we derive expressions for the simultaneous closeness probabilities of the progressively censored OS to population quantiles. Explicit expressions are deduced for the cases when the underlying distribution has bounded and unbounded supports. Illustrations are provided for the cases of exponential, uniform and normal distributions for various progressive type-II right-censoring schemes and different quantiles. Finally, an extension to the case of generalized OS is outlined.