Head Impact Situations in Professional Football (Soccer)

To assess head impact incidents (HIIs) and to distinguish diagnosed head injuries from other incidents, a video observation analysis of match HIIs was conducted in the German Bundesliga (2017/18 season). Video recordings of each match were screened to identify the respective events. Head injury data were identified by a prospective injury registry. HII and head injury incidence rates (IR) were calculated with 95 % CIs. The total number of HIIs was 1362 corresponding to an IR of 134.9/1000 match hours (95% CI 127.9–142.2). In 123 HII (IR 12.2, 95% CI 10.2–14.5) the contact was classified as severe. Head contact with the opponent was the most frequent cause (85%). The most frequent mechanism was in 44% (combined) the arm and elbow-to-head, followed by head-to-head and hand-to-head contacts (each 13%). In 58%, the HIIs occurred during header duels. Twenty-nine head injuries were recorded (IR 2.9, 95% CI 2.0–4.1). Concussions/traumatic brain injuries accounted for 48%, head/facial fractures 24%, head/facial contusions 21%, and lacerations/abrasions 7%. The number of HIIs not classified as concussions/more severe trauma was high. Identification of HIIs and head injury severity should be improved during on-field assessment as many head injuries might go unrecognised based on the large number of HIIs

Kinetics of Olivine Weathering in Seawater: An Experimental Study

Enhanced weathering of mafic and ultra-mafic minerals has been suggested as a strategy for carbon dioxide removal (CDR) and a contribution to achieve a balance between global CO2 sources and sinks (net zero emission). This study was designed to assess CDR by dissolution of ultramafic sand (UMS) in artificial seawater (ASW). Fine grained UMS with an olivine content of ~75% was reacted in ASW for up to 134 days at 1 bar and 21.5–23.9°C. A decline in total alkalinity (TA) was observed over the course of the experiments. This unexpected result indicates that TA removal via precipitation of cation-rich authigenic phases exceeded the production of TA induced by olivine dissolution. The TA decline was accompanied by a decrease in dissolved inorganic carbon and Ca concentrations presumably induced by CaCO3 precipitation. Temporal changes in dissolved Si, Ca, Mg, and TA concentrations observed during the experiments were evaluated by a numerical model to identify secondary mineral phases and quantify rates of authigenic phase formation. The modeling indicates that CaCO3, FeOOH and a range of Mg-Si-phases were precipitated during the experiments. Chemical analysis of precipitates and reacted UMS surfaces confirmed that these authigenic phases accumulated in the batch reactors. Nickel released during olivine dissolution, a potential toxic element for certain organisms, was incorporated in the secondary phases and is thus not a suitable proxy for dissolution rates as proposed by earlier studies. The overall reaction stoichiometry derived from lab experiments was applied in a box model simulating atmospheric CO2 uptake in a continental shelf setting induced by olivine addition. The model results indicate that CO2 uptake is reduced by a factor of 5 due to secondary mineral formation and the buffering capacity of seawater. In comparable natural settings, olivine addition may thus be a less efficient CDR method than previously believed

Improved Characterization of Visual Evoked Potentials in Multiple Sclerosis by Topographic Analysis

In multiple sclerosis (MS), the combination of visual, somatosensory and motor evoked potentials (EP) has been shown to be highly correlated with the Expanded Disability Severity Scale (EDSS) and to predict the disease course. In the present study, we explored whether the significance of the visual EP (VEP) can be improved with multichannel recordings (204 electrodes) and topographic analysis (tVEP). VEPs were analyzed in 83 MS patients (median EDSS 2.0; 52% with history of optic neuritis; hON) and 47 healthy controls (HC). TVEP components were automatically defined on the basis of spatial similarity between the scalp potential fields (topographic maps) of single subjects' VEPs and reference maps generated from HC. Non-ambiguous measures of latency, amplitude and configuration were derived from the maps reflecting the P100 component. TVEP was compared to conventional analysis (cVEP) with respect to reliability in HC, validity using descriptors of logistic regression models, and sensitivity derived from receiver operating characteristics curves. In tVEP, reliability tended to be higher for measurement of amplitude (p=0.06). Regression models on diagnosis (MS vs. HC) and hON were more favorable using tVEP- versus cVEP-predictors. Sensitivity was increased in tVEP versus cVEP: 72% versus 60% for diagnosis, and 88% versus 77% for hON. The advantage of tVEP was most pronounced in pathological VEPs, in which cVEPs were often ambiguous. TVEP is a reliable, valid, and sensitive method of objectively quantifying pathological VEP in particular. In combination with other EP modalities, tVEP may improve the monitoring of disease course in MS

Brain Exposure to Piperacillin in Acute Hemorrhagic Stroke Patients Assessed by Cerebral Microdialysis and Population Pharmacokinetics

Background The broad antibacterial spectrum of piperacillin/tazobactam makes the combination suitable for the treatment of nosocomial bacterial central nervous system (CNS) infections. As limited data are available regarding piperacillin CNS exposure in patients without or with low-grade inflammation, a clinical study was conducted (1) to quantify CNS exposure of piperacillin by cerebral microdialysis and (2) to evaluate different dosing regimens in order to improve probability of target attainment (PTA) in brain. Methods Ten acute hemorrhagic stroke patients (subarachnoid hemorrhage, n = 6; intracerebral hemorrhage, n = 4) undergoing multimodality neuromonitoring received 4 g piperacillin/0.5 g tazobactam every 8 h by 30-min infusions for the management of healthcare-associated pneumonia. Cerebral microdialysis was performed as part of the clinical neuromonitoring routine, and brain interstitial fluid samples were retrospectively analyzed for piperacillin concentrations after the first and after multiple doses for at least 5 days and quantified by high-performance liquid chromatography. Population pharmacokinetic modeling and Monte Carlo simulations with various doses and types of infusions were performed to predict exposure. A T->MIC of 50% was selected as pharmacokinetic/pharmacodynamic target parameter. Results Median peak concentrations of unbound piperacillin in brain interstitial space fluid were 1.16 (range 0.08-3.59) and 2.78 (range 0.47-7.53) mg/L after the first dose and multiple doses, respectively. A one-compartment model with a transit compartment and a lag time (for the first dose) between systemic and brain exposure was appropriate to describe the brain concentrations. Bootstrap median estimates of the parameters were: transfer rate from plasma to brain (0.32 h(-1)), transfer rate from brain to plasma (7.31 h(-1)), and lag time [2.70 h (coefficient of variation 19.7%)]. The simulations suggested that PTA would exceed 90% for minimum inhibitory concentrations (MICs) up to 0.5 mg/L and 1 mg/L at a dose of 12-16 and 24 g/day, respectively, regardless of type of infusion. For higher MICs, PTA dropped significantly. Conclusion Limited CNS exposure of piperacillin might be an obstacle in treating patients without general meningeal inflammation except for infections with highly susceptible pathogens. Brain exposure of piperacillin did not improve significantly with a prolongation of infusions

Distribution of spleen tyrosine kinase and tau phosphorylated at tyrosine 18 in a mouse model of tauopathy and in the human hippocampus

Purpose: Spleen tyrosine kinase (Syk) has been shown to phosphorylate tyrosine 18 of tau in vitro. It has been proposed that increased immunoreactivity for double-phosphorylated Syk in hippocampal neurons of Alzheimer's disease cases indicates a not yet defined neurodegenerative process. To investigate this possibility we have studied Syk and tau phosphorylated at tyrosine 18 (pTyr18) in transgenic mice and human hippocampi. Methods: We performed immunohistochemistry, immunofluorescence labeling and Western blotting and compared the distribution of Syk double-phosphorylated at tyrosines 525 and 526 and pTyr18 in human tau transgenic pR5 mice and human hippocampi with low and high Braak stages for neurofibrillary tangle pathology. Results: pTyr18 appeared early during the course of neurodegeneration in pR5 mice and was widely distributed in the pR5 brain, including neuronal somata and fiber tracts. In contrast, only strongly pTyr18- and AT100-(tau phosphorylated at Thr212 and Ser214) positive neurons with a fibrillary tau pathology in old pR5 mice and microglia displayed immunoreactivity for double-phosphorylated Syk. In human hippocampi, phosphorylated Syk was mainly present in granulovacuolar inclusions in hippocampal pyramidal neurons and did not co-locate with pTyr18 in these neurons. We observed pTyr18-positive neurons and neurons with granular pSyk immunoreactivity already at early Braak stages and their number was markedly increased in Braak stage VI. Conclusion: Syk appears unlikely to be the major kinase that phosphorylates tyrosine 18 of tau in tauopathy. It possibly phosphorylates tyrosine 18 of tau and regulates other tau kinases in neurons with a fibrillary tau pathology. (C) 2017 Elsevier B.V. All rights reserved

Probabilistic Learning Approaches for Indexing and Retrieval with the TREC-2 Collection

In this paper, we describe the application of probabilistic models for indexing and retrieval with the TREC-2 collection. This database consists of about a million documents (2 gigabytes of data) and 100 queries (50 routing and 50 adhoc topics). For document indexing, we use a description-oriented approach which exploits relevance feedback data in order to produce a probabilistic indexing with single terms as well as with phrases. With the adhoc queries, we present a new query term weighting method based on a training sample of other queries. For the routing queries, the RPI model is applied which combines probabilistic indexing with query term weighting based on query-specific feedback data. The experimental results of our approach show very good performance for both types of queries. 1 Introduction The good TREC-1 results of our group described in [Fuhr & Buckley 93] have confirmed the general concept of probabilistic retrieval as a learning approach. In this paper, we describe some..

Parkinson disease and the risk of epileptic seizures

To assess the association between incident Parkinson disease (PD) and subsequent incident epileptic seizures.; We conducted a retrospective cohort study with a nested case-control analysis using data from the U.K. Clinical Practice Research Datalink. We identified patients aged ≥40 years with an incident diagnosis of PD between 1995 and 2016 and a matched comparison group of PD-free individuals. We calculated crude incidence rates (IRs) with 95% confidence intervals (CIs) of epileptic seizures in PD patients and the PD-free comparison group, and corresponding crude incidence rate ratios (IRRs). In the nested case-control analysis, we calculated adjusted odds ratios (adj. ORs) of incident PD among cases with incident epileptic seizures and seizure-free controls overall and stratified by various seizure-provoking comorbidities.; Among 23,086 incident PD patients and 92,343 PD-free individuals, we identified 898 patients with incident epileptic seizures. The crude IR of epileptic seizures in PD patients was 266.7/100,000 person-years (95% CI = 235.6-297.7), and in PD-free individuals it was 112.4/100,000 person-years (95% CI = 103.5-121.3; IRR = 2.37, 95% CI = 2.06-2.73). The adj. OR of epileptic seizures was 1.68 (95% CI = 1.43-1.98) in PD patients compared with PD-free individuals. PD patients with comorbid brain disorders (adj. OR = 12.36, 95% CI = 8.74-17.48) or with > 1 seizure-provoking comorbidity (adj. OR = 13.24, 95% CI = 10.15-17.25) were at the highest risk of epileptic seizures compared with PD-free individuals with no seizure-provoking comorbidities.; This study suggests that incident PD is associated with an increased risk of incident epileptic seizures