Publications

23 Dec 2022

rTMS treatment for hypokinetic dysarthria in Parkinson's disease enhances white matter integrity of the auditory-motor loop

Background: In our previous study, repeated sessions of repetitive transcranial magnetic stimulation (rTMS) over the auditory feedback area were shown to improve hypokinetic dysarthria (HD) in Parkinson's disease (PD) and led to changes in functional connectivity within the left-sided articulatory networks.

Objectives: We analyzed data from this previous study and assessed the effects of rTMS for HD in PD on the diffusion parameters of the left anterior arcuate fasciculus (AAF), which connects the auditory feedback area with motor regions involved in articulation.

Methods: Patients were assigned to ten sessions of real or sham 1 Hz stimulation over the right posterior superior temporal gyrus (STG). Stimulation effects were evaluated using magnetic resonance diffusion tensor imaging and by speech therapist using a validated tool (Phonetics score of the Dysarthric Profile) at baseline, immediately after 2 weeks of stimulation, and at follow-up visits at week 6 and 10 after the baseline.

19 Dec 2022

Impact of analgesic regimen on patient outcome following subarachnoid hemorrhage: positive adjuvant effects of metamizole

Introduction: Various analgesics are used to control intense headaches in patients following subarachnoid hemorrhage. In addition to pain control, it has been shown that some analgesics can affect various pathophysiological cascades. Therefore, we devised a study to assess whether the use of metamizole has a significant impact on the development of ischemic complications, hydrocephalus, and the overall outcome in patients following aneurysmal subarachnoid hemorrhage in the context of the other non-opioids and opioids effects.

Methods: In our retrospective, single-center cohort study, we enrolled 192 patients diagnosed with subarachnoid hemorrhage. We recorded their initial clinical status, comorbidities, and the daily dosage of analgesics over 14 days of hospitalization after the onset of subarachnoid hemorrhage. Using univariate and subsequent multivariate logistic regression analysis, we assessed the influence of various factors, including analgesics, on the development of delayed cerebral ischemia and hydrocephalus, as well as on 2-week and 6-month outcomes.

19 Dec 2022

The landscape of tumor cell states and spatial organization in H3-K27M mutant diffuse midline glioma across age and location

Histone 3 lysine27-to-methionine (H3-K27M) mutations most frequently occur in diffuse midline gliomas (DMGs) of the childhood pons but are also increasingly recognized in adults. Their potential heterogeneity at different ages and midline locations is vastly understudied. Here, through dissecting the single-cell transcriptomic, epigenomic and spatial architectures of a comprehensive cohort of patient H3-K27M DMGs, we delineate how age and anatomical location shape glioma cell-intrinsic and -extrinsic features in light of the shared driver mutation. We show that stem-like oligodendroglial precursor-like cells, present across all clinico-anatomical groups, display varying levels of maturation dependent on location. We reveal a previously underappreciated relationship between mesenchymal cancer cell states and age, linked to age-dependent differences in the immune microenvironment. Further, we resolve the spatial organization of H3-K27M DMG cell populations and identify a mitotic oligodendroglial-lineage niche.

9 Dec 2022

A new approach to the determination of tubular membrane capacitance: passive membrane electrical properties under reduced electrical conductivity of the extracellular solution

The transverse-axial tubular system (tubular system) of cardiomyocytes plays a key role in excitation-contraction coupling. To determine the area of the tubular membrane in relation to the area of the surface membrane, indirect measurements through the determination of membrane capacitances are currently used in addition to microscopic methods. Unlike existing electrophysiological methods based on an irreversible procedure (osmotic shock), the proposed new approach uses a reversible short-term intermittent increase in the electrical resistance of the extracellular medium. The resulting increase in the lumen resistance of the tubular system makes it possible to determine separate capacitances of the tubular and surface membranes. Based on the analysis of the time course of the capacitive current, computational relations were derived to quantify the elements of the electrical equivalent circuit of the measured cardiomyocyte including both capacitances. 

9 Dec 2022

Use of free radial forearm and pronator quadratus muscle flap: Anatomical study and clinical application

The authors present an anatomical study and clinical experience with radial forearm flap (RFF) and pronator quadratus muscle (PQM) application in the reconstruction of various body areas. The aim was to describe the anatomical placement and proportions of the PQM, the anatomical location of the major arterial branch of the radial artery supplying the PQM, and the application of this knowledge in clinical practice. The anatomical study was based upon an analysis of 13 fresh adult cadaver upper extremities, of which nine were female and four male; both arms from the same donors were used in four cases. The study of the PQM was performed using a dye-containing intraarterial injection, standard macro- and micro-preparation techniques, and chemical digestion. The data on the PQM size in males and females, thickness of the radial artery branch (the principal artery nourishing the muscle), and its position were analysed. The radial artery branch nourishing the PQM was identified in all cadaveric specimens of the anatomical study.

9 Dec 2022

Immune system disorders in the early post-injury period in patients after severe brain injury from the perspective of the severity of the injury

Background: Brain injuries are the most common cause of death in productive age. Besides the extent of the injury, other systemic factors can also affect the outcome. Patients suffering from severe brain injury often experience extracranial inflammatory complications during the early period of treatment. Here, we investigate the changes in immunity in patients with brain injury.

Methods: 121 patients and 92 healthy controls were included in the research. Blood samples were collected on admission and analyzed by flow cytometry and biochemical methods. Multiple clusters of differentiation (CD) and antibody levels were investigated. The results were compared between patients and controls. In addition, results of two classes of severity (Glasgow Coma Scale, GCS, of 3-5 vs. 6-8) were also compared.

9 Dec 2022

Model-informed unsupervised deep learning approaches to frequency and phase correction of MRS signals

Purpose: A supervised deep learning (DL) approach for frequency and phase correction (FPC) of MRS data recently showed encouraging results, but obtaining transients with labels for supervised learning is challenging. This work investigates the feasibility and efficiency of unsupervised deep learning-based FPC.

Methods: Two novel deep learning-based FPC methods (deep learning-based Cr referencing and deep learning-based spectral registration), which use a priori physics domain knowledge, are presented. The proposed networks were trained, validated, and evaluated using simulated, phantom, and publicly accessible in vivo MEGA-edited MRS data. The performance of our proposed FPC methods was compared with other generally used FPC methods, in terms of precision and time efficiency. A new measure was proposed in this study to evaluate the FPC method performance. 

9 Dec 2022

Perinatal maternal mental health and amygdala morphology in young adulthood

The pre- and perinatal environment is thought to play a critical role in shaping brain development. Specifically, maternal mental health and maternal care have been shown to influence offspring brain development in regions implicated in emotional regulation such as the amygdala. In this study, we used data from a neuroimaging follow-up of a prenatal birth-cohort, the European Longitudinal Study of Pregnancy and Childhood, to investigate the impact of early postnatal maternal anxiety/co-dependence, and prenatal and early-postnatal depression and dysregulated mood on amygdala volume and morphology in young adulthood (n = 103). We observed that in typically developing young adults, greater maternal anxiety/co-dependence after birth was significantly associated with lower volume (right: t = -2.913, p = 0.0045, β = -0.523; left: t = -1.471, p = 0.144, β = -0.248) and non-significantly associated with surface area (right: t = -3.502, q = 0.069, <10%FDR, β = -0.090, left: t = -3.137, q = 0.117, <10%FDR, = -0.088) of the amygdala in young adulthood.

7 Dec 2022

Inter-individual differences in baseline dynamic functional connectivity are linked to cognitive aftereffects of tDCS

Transcranial direct current stimulation (tDCS) has the potential to modulate cognitive training in healthy aging; however, results from various studies have been inconsistent. We hypothesized that inter-individual differences in baseline brain state may contribute to the varied results. We aimed to explore whether baseline resting-state dynamic functional connectivity (rs-dFC) and/or conventional resting-state static functional connectivity (rs-sFC) may be related to the magnitude of cognitive aftereffects of tDCS. To achieve this aim, we used data from our double-blind randomized sham-controlled cross-over tDCS trial in 25 healthy seniors in which bifrontal tDCS combined with cognitive training had induced significant behavioral aftereffects. We performed a backward regression analysis including rs-sFC/rs-dFC measures to explain the variability in the magnitude of tDCS-induced improvements in visual object-matching task (VOMT) accuracy. Rs-dFC analysis revealed four rs-dFC states.

29 Nov 2022

Geometric Control of Cell Behavior by Biomolecule Nanodistribution

Many dynamic interactions within the cell microenvironment modulate cell behavior and cell fate. However, the pathways and mechanisms behind cell-cell or cell-extracellular matrix interactions remain understudied, as they occur at a nanoscale level. Recent progress in nanotechnology allows for mimicking of the microenvironment at nanoscale <i>in vitro</i>; electron-beam lithography (EBL) is currently the most promising technique. Although this nanopatterning technique can generate nanostructures of good quality and resolution, it has resulted, thus far, in the production of only simple shapes (e.g., rectangles) over a relatively small area (100 × 100 μm), leaving its potential in biological applications unfulfilled. Here, we used EBL for cell-interaction studies by coating cell-culture-relevant material with electron-conductive indium tin oxide, which formed nanopatterns of complex nanohexagonal structures over a large area (500 × 500 μm).

16 Nov 2022

Global Impact of the COVID-19 Pandemic on Stroke Volumes and Cerebrovascular Events: One-Year Follow-up

Background and objectives: Declines in stroke admission, intravenous thrombolysis, and mechanical thrombectomy volumes were reported during the first wave of the COVID-19 pandemic. There is a paucity of data on the longer-term effect of the pandemic on stroke volumes over the course of a year and through the second wave of the pandemic. We sought to measure the impact of the COVID-19 pandemic on the volumes of stroke admissions, intracranial hemorrhage (ICH), intravenous thrombolysis (IVT), and mechanical thrombectomy over a one-year period at the onset of the pandemic (March 1, 2020, to February 28, 2021) compared with the immediately preceding year (March 1, 2019, to February 29, 2020).

Methods: We conducted a longitudinal retrospective study across 6 continents, 56 countries, and 275 stroke centers. 

16 Nov 2022

Deep Brain Stimulation during Pregnancy and Delivery: Review of Current Literature

Deep brain stimulation (DBS) is an established method in the treatment of not only Parkinson's disease motor complications but also dystonia and tremor, and there are data supporting the efficacy of DBS in epilepsy and some psychiatric problems. The alleviation of the neurologic problems may enable females of childbearing age to consider pregnancy because of being able to take care of their child. The aim of the study is to provide a review of the data available on the effect of DBS on the course of pregnancy and delivery in patients suffering from diseases amenable for DBS treatment (Parkinson's disease, dystonia, obsessive compulsive disorder, Tourette's syndrome, epilepsy). Although data available in the literature on pregnancy and childbirth in patients with an implanted active DBS system are limited to small case series and case reports, the number of younger patients implanted with DBS systems will potentially require more attention beyond specialized DBS centers.

16 Nov 2022

A Randomized, Double-Blind, Placebo-Controlled Trial of the Corticosteroid-Sparing Effects of Immunoglobulin in Myasthenia Gravis

Background and objectives: Myasthenia gravis (MG) is an autoimmune disease characterized by dysfunction at the neuromuscular junction. Treatment frequently includes corticosteroids (CS) and intravenous immunoglobulin (IVIG). This study was conducted to determine if immune globulin (human), 10% caprylate/chromatography purified (IGIV-C) could facilitate CS dose reduction in CS-dependent MG patients.

Methods: In this randomized, double-blind, placebo-controlled trial, CS-dependent MG patients (MGFA class II-Iva; AChR+) received a loading dose of 2 g/kg IGIV-C over 2 days (maximum 80 g/day) or placebo at week 0 (baseline). Maintenance doses (1 g/kg IGIV-C or placebo) were administered every three weeks through week 36. Tapering of CS was initiated at week 9 and continued through week 36 unless the patient worsened (QMG score ≥ 4 points from baseline). 

16 Nov 2022

Current Management of Generalized Convulsive Status Epilepticus in Children

Keywords: burst-suppression pattern; children; generalized convulsive status epilepticus; management; propofol infuse syndrome.

16 Nov 2022

Incidence of Emergence Delirium in the Pediatric PACU: Prospective Observational Trial

Emergence delirium (ED) is a postoperative complication in pediatric anesthesia characterized by perception and psychomotor disorder and has a negative impact on morbidity in the form of maladaptive behavior, which can last weeks after anesthesia. Patients with developed ED present with psychomotor anxiety, agitation, and are at higher risk of unintentional extraction of an intravenous cannula, self-harm and nausea and vomiting. The described incidence of ED varies between 25-80%, with a higher prevalence among children younger than 6 years of age. We aimed to determine the incidence of ED in pediatric patients (&gt;1 month) after general anesthesia in the post-anesthesia care unit (PACU), using Paediatric Anaesthesia Emergence Delirium (PAED) score, Watcha score and Richmond agitation and sedation scale (RASS). The incidence of ED was the highest in the PAED score with cutoff ≥10 points (89.0%, n = 1088). When using PAED score &gt;12 points, ED incidence was 19.3% (n = 236). The lowest incidence was described by Watcha and RASS scores, 18.8% (n = 230) vs. 18.1% (n = 221), respectively.

11 Nov 2022

Astrocyte reactivity in the glia limitans superficialis of the rat medial prefrontal cortex following sciatic nerve injury

The glia limitans superficialis (GLS) on the rodent cortical surface consists of astrocyte bodies intermingled with their cytoplasmic processes. Many studies have observed astrocyte reactivity in the medial prefrontal cortex (mPFC) parenchyma induced by a peripheral nerve injury, while the response of GLS astrocytes is still not fully understood. The aim of our study was to identify the reactivity of rat GLS astrocytes in response to sciatic nerve compression (SNC) over different time periods.

The alteration of GLS astrocyte reactivity was monitored using immunofluorescence (IF) intensities of glial fibrillary acidic protein (GFAP), glutamine synthetase (GS), and NFκBp65. Our results demonstrated that SNC induced GLS astrocyte reactivity seen as increased intensities of GFAP-IF, and longer extensions of cytoplasmic processes into lamina I. First significant increase of GFAP-IF was observed on post-operation day 7 (POD7) after SNC with further increases on POD14 and POD21. 

11 Nov 2022

Safety and Outcome of Revascularization Treatment in Patients With Acute Ischemic Stroke and COVID-19: The Global COVID-19 Stroke Registry

Background and objectives: COVID-19 related inflammation, endothelial dysfunction and coagulopathy may increase the bleeding risk and lower efficacy of revascularization treatments in patients with acute ischemic stroke. We aimed to evaluate the safety and outcomes of revascularization treatments in patients with acute ischemic stroke and COVID-19.

Methods: Retrospective multicenter cohort study of consecutive patients with acute ischemic stroke receiving intravenous thrombolysis (IVT) and/or endovascular treatment (EVT) between March 2020 and June 2021, tested for SARS-CoV-2 infection. With a doubly-robust model combining propensity score weighting and multivariate regression, we studied the association of COVID-19 with intracranial bleeding complications and clinical outcomes. Subgroup analyses were performed according to treatment groups (IVT-only and EVT).

20 Oct 2022

Teaching Video NeuroImage: Amaurosis Fugax Due to Recurrent Central Retinal Artery Occlusion by Microemboli

A previously healthy 71-year-old woman with hypercholesterolemia and current tobacco use presented with transient painless vision loss in the left eye without other neurologic abnormalities.

The 30-second episodes, followed by a recovery, repeated in 2- to 3-minute intervals.¹ Microemboli passing through central retinal artery (CRA) vasculature (Video 1) originated from a complicated atherosclerotic plaque in the left internal carotid artery (Figure).

After receiving intravenous thrombolysis 5 hours after symptom onset,² she reported a scotoma in the inferior part of her left eye, which persisted 2 years later.

Retinal embolism from carotid artery disease is the most common cause of CRA occlusion.