SH3TC2, a protein mutant in Charcot-Marie-Tooth neuropathy, links peripheral nerve myelination to endosomal recycling

Patients with Charcot-Marie-Tooth neuropathy and gene targeting in mice revealed an essential role for the SH3TC2 gene in peripheral nerve myelination. SH3TC2 expression is restricted to Schwann cells in the peripheral nervous system, and the gene product, SH3TC2, localizes to the perinuclear recycling compartment. Here, we show that SH3TC2 interacts with the small guanosine triphosphatase Rab11, which is known to regulate the recycling of internalized membranes and receptors back to the cell surface. Results of protein binding studies and transferrin receptor trafficking are in line with a role of SH3TC2 as a Rab11 effector molecule. Consistent with a function of Rab11 in Schwann cell myelination, SH3TC2 mutations that cause neuropathy disrupt the SH3TC2/Rab11 interaction, and forced expression of dominant negative Rab11 strongly impairs myelin formation in vitro. Our data indicate that the SH3TC2/Rab11 interaction is relevant for peripheral nerve pathophysiology and place endosomal recycling on the list of cellular mechanisms involved in Schwann cell myelinatio

Gene expression analysis of cell death induction by Taurolidine in different malignant cell lines

<p>Abstract</p> <p>Background</p> <p>The anti-infective agent Taurolidine (TRD) has been shown to have cell death inducing properties, but the mechanism of its action is largely unknown. The aim of this study was to identify potential common target genes modulated at the transcriptional level following TRD treatment in tumour cell lines originating from different cancer types.</p> <p>Methods</p> <p>Five different malignant cell lines (HT29, Chang Liver, HT1080, AsPC-1 and BxPC-3) were incubated with TRD (100 μM, 250 μM and 1000 μM). Proliferation after 8 h and cell viability after 24 h were analyzed by BrdU assay and FACS analysis, respectively. Gene expression analyses were carried out using the <it>Agilent </it>-microarray platform to indentify genes which displayed conjoint regulation following the addition of TRD in all cell lines. Candidate genes were subjected to <it>Ingenuity Pathways Analysis </it>and selected genes were validated by qRT-PCR and Western Blot.</p> <p>Results</p> <p>TRD 250 μM caused a significant inhibition of proliferation as well as apoptotic cell death in all cell lines. Among cell death associated genes with the strongest regulation in gene expression, we identified pro-apoptotic transcription factors (EGR1, ATF3) as well as genes involved in the ER stress response (PPP1R15A), in ubiquitination (TRAF6) and mitochondrial apoptotic pathways (PMAIP1).</p> <p>Conclusions</p> <p>This is the first conjoint analysis of potential target genes of TRD which was performed simultaneously in different malignant cell lines. The results indicate that TRD might be involved in different signal transduction pathways leading to apoptosis.</p

Progression characteristics of the European Friedreich's Ataxia Consortium for Translational Studies (EFACTS): a 4-year cohort study

BACKGROUND: The European Friedreich's Ataxia Consortium for Translational Studies (EFACTS) investigates the natural history of Friedreich's ataxia. We aimed to assess progression characteristics and to identify patient groups with differential progression rates based on longitudinal 4-year data to inform upcoming clinical trials in Friedreich's ataxia. METHODS: EFACTS is a prospective, observational cohort study based on an ongoing and open-ended registry. Patients with genetically confirmed Friedreich's ataxia were seen annually at 11 clinical centres in seven European countries (Austria, Belgium, France, Germany, Italy, Spain, and the UK). Data from baseline to 4-year follow-up were included in the current analysis. Our primary endpoints were the Scale for the Assessment and Rating of Ataxia (SARA) and the activities of daily living (ADL). Linear mixed-effect models were used to analyse annual disease progression for the entire cohort and subgroups defined by age of onset and ambulatory abilities. Power calculations were done for potential trial designs. This study is registered with ClinicalTrials.gov, NCT02069509. FINDINGS: Between Sept 15, 2010, and Nov 20, 2018, of 914 individuals assessed for eligibility, 602 patients were included. Of these, 552 (92%) patients contributed data with at least one follow-up visit. Annual progression rate for SARA was 0·82 points (SE 0·05) in the overall cohort, and higher in patients who were ambulatory (1·12 [0·07]) than non-ambulatory (0·50 [0·07]). ADL worsened by 0·93 (SE 0·05) points per year in the entire cohort, with similar progression rates in patients who were ambulatory (0·94 [0·07]) and non-ambulatory (0·91 [0·08]). Although both SARA and ADL showed slightly greater worsening in patients with typical onset (symptom onset at ≤24 years) than those with late onset (symptom onset ≥25 years), differences in progression slopes were not significant. For a 2-year parallel-group trial, 230 (115 per group) patients would be required to detect a 50% reduction in SARA progression at 80% power: 118 (59 per group) if only individuals who are ambulatory are included. With ADL as the primary outcome, 190 (95 per group) patients with Friedreich's ataxia would be needed, and fewer patients would be required if only individuals with early-onset are included. INTERPRETATION: Our findings for stage-dependent progression rates have important implications for clinicians and researchers, as they provide reliable outcome measures to monitor disease progression, and enable tailored sample size calculation to guide upcoming clinical trial designs in Friedreich's ataxia. FUNDING: European Commission, Voyager Therapeutics, and EuroAtaxia

Prediction of the disease course in Friedreich ataxia

We explored whether disease severity of Friedreich ataxia can be predicted using data from clinical examinations. From the database of the European Friedreich Ataxia Consortium for Translational Studies (EFACTS) data from up to five examinations of 602 patients with genetically confirmed FRDA was included. Clinical instruments and important symptoms of FRDA were identified as targets for prediction, while variables such as genetics, age of disease onset and first symptom of the disease were used as predictors. We used modelling techniques including generalised linear models, support-vector-machines and decision trees. The scale for rating and assessment of ataxia (SARA) and the activities of daily living (ADL) could be predicted with predictive errors quantified by root-mean-squared-errors (RMSE) of 6.49 and 5.83, respectively. Also, we were able to achieve reasonable performance for loss of ambulation (ROC-AUC score of 0.83). However, predictions for the SCA functional assessment (SCAFI) and presence of cardiological symptoms were difficult. In conclusion, we demonstrate that some clinical features of FRDA can be predicted with reasonable error; being a first step towards future clinical applications of predictive modelling. In contrast, targets where predictions were difficult raise the question whether there are yet unknown variables driving the clinical phenotype of FRDA

Pyrethroid treatment of cattle for tsetse control: Reducing its impact on dung fauna

Background: African trypansomiases of humans and animals can be controlled by attacking the vectors,various species of tsetse fly. Treatment of cattle with pyrethroids to kill tsetse as they feed is the most cost-effective method. However, such treatments can contaminate cattle dung, thereby killing the fauna which disperse the dung and so play an important role in soil fertility. Hence there is a need to identify cost-effective methods of treating cattle with minimal impact on dung fauna. Methodology/Principal Findings: We used dung beetles to field bioassay the levels of dung contamination following the use of spray and pour-on formulations of deltamethrin, applied to various parts of the body of cattle in Zimbabwe. Results suggested that dung was contaminated by contact with insecticide on the body surface as the cattle defecated, and by ingestion of insecticide as the cattle licked themselves. Death of dung beetles was reduced to negligible levels by using only the spray and applying it to the legs and belly or legs alone, i.e., places where most tsetse feed. Conclusion/Significance: The restricted applications suitable for minimising the impact on dung fauna have the collateral benefits of improving the economy and convenience of cattle treatments for tsetse control. The demonstration of collateral benefits is one of the surest ways of promoting environmentally friendly procedures

Potential climatic transitions with profound impact on Europe

We discuss potential transitions of six climatic subsystems with large-scale impact on Europe, sometimes denoted as tipping elements. These are the ice sheets on Greenland and West Antarctica, the Atlantic thermohaline circulation, Arctic sea ice, Alpine glaciers and northern hemisphere stratospheric ozone. Each system is represented by co-authors actively publishing in the corresponding field. For each subsystem we summarize the mechanism of a potential transition in a warmer climate along with its impact on Europe and assess the likelihood for such a transition based on published scientific literature. As a summary, the ‘tipping’ potential for each system is provided as a function of global mean temperature increase which required some subjective interpretation of scientific facts by the authors and should be considered as a snapshot of our current understanding. <br/

International Paediatric Mitochondrial Disease Scale

Objective: There is an urgent need for reliable and universally applicable outcome measures for children with mitochondrial diseases. In this study, we aimed to adapt the currently available Newcastle Paediatric Mitochondrial Disease Scale (NPMDS) to the International Paediatric Mitochondrial Disease Scale (IPMDS) during a Delphi-based process with input from international collaborators, patients and caretakers, as well as a pilot reliability study in eight patients. Subsequently, we aimed to test the feasibility, construct validity and reliability of the IPMDS in a multicentre study. Methods: A clinically, biochemically and genetically heterogeneous group of 17 patients (age 1.6–16 years) from five different expert centres from four different continents were evaluated in this study. Results: The feasibility of the IPMDS was good, as indicated by a low number of missing items (4 %) and the positive evaluation of patients, parents and users. Principal component analysis of our small sample identified three factors, which explained 57.9 % of the variance. Good construct validity was found using hypothesis testing. The overall interrater reliability was good [median intraclass correlation coefficient for agreement between raters (ICCagreement) 0.85; range 0.23–0.99). Conclusion: In conclusion, we suggest using the IPMDS for assessing natural history in children with mitochondrial diseases. These data should be used to further explore construct validity of the IPMDS and to set age limits. In parallel, responsiveness and the minimal clinically important difference should be studied to facilitate sample size calculations in future clinical trials

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

The future sea-level rise contribution of Greenland’s glaciers and ice caps

We calculate the future sea-level rise contribution from the surface mass balance of all of Greenland's glaciers and ice caps (GICs, ~90 000 km2) using a simplified energy balance model which is driven by three future climate scenarios from the regional climate models HIRHAM5, RACMO2 and MAR. Glacier extent and surface elevation are modified during the mass balance model runs according to a glacier retreat parameterization. Mass balance and glacier surface change are both calculated on a 250 m resolution digital elevation model yielding a high level of detail and ensuring that important feedback mechanisms are considered. The mass loss of all GICs by 2098 is calculated to be 2016 ± 129 Gt (HIRHAM5 forcing), 2584 ± 109 Gt (RACMO2) and 3907 ± 108 Gt (MAR). This corresponds to a total contribution to sea-level rise of 5.8 ± 0.4, 7.4 ± 0.3 and 11.2 ± 0.3 mm, respectively. Sensitivity experiments suggest that mass loss could be higher by 20–30% if a strong lowering of the surface albedo were to take place in the future. It is shown that the sea-level rise contribution from the north-easterly regions of Greenland is reduced by increasing precipitation while mass loss in the southern half of Greenland is dominated by steadily decreasing summer mass balances. In addition we observe glaciers in the north-eastern part of Greenland changing their characteristics towards greater activity and mass turnover

NfL and pNfH are increased in Friedreich's ataxia

Objective: To assess neurofilaments as neurodegenerative biomarkers in serum of patients with Friedreich’s ataxia. / Methods: Single molecule array measurements of neurofilament light (NfL) and heavy chain (pNfH) in 99 patients with genetically confirmed Friedreich’s ataxia. Correlation of NfL/pNfH serum levels with disease severity, disease duration, age, age at onset, and GAA repeat length. / Results: Median serum levels of NfL were 21.2 pg/ml (range 3.6–49.3) in controls and 26.1 pg/ml (0–78.1) in Friedreich’s ataxia (p = 0.002). pNfH levels were 23.5 pg/ml (13.3–43.3) in controls and 92 pg/ml (3.1–303) in Friedreich’s ataxia (p = 0.0004). NfL levels were significantly increased in younger patients (age 16–31 years, p < 0.001) and patients aged 32–47 years (p = 0.008), but not in patients of age 48 years and older (p = 0.41). In a longitudinal assessment, there was no difference in NfL levels in 14 patients with repeated sampling 2 years after baseline measurement. Levels of NfL correlated inversely with GAA1 repeat length (r = − 0.24, p = 0.02) but not with disease severity (r = − 0.13, p = 0.22), disease duration (r = − 0.06, p = 0.53), or age at onset (r = 0.05, p = 0.62). / Conclusion: Serum levels of NfL and pNfH are elevated in Friedreich’s ataxia, but differences to healthy controls decrease with increasing age. Long-term longitudinal data are required to explore whether this reflects a selection bias from early death of more severely affected individuals or a slowing down of the neurodegenerative process with age. In a pilot study over 2 years of follow-up—a period relevant for biomarkers indicating treatment effects—we found NfL levels to be stable