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Objective To assess whole brain and central brain atrophy as well as their differential relation to memory, cognitive performance, fatigue, depression and quality of life in patients with relapsingremitting multiple sclerosis (RRMS). Methods A 3D flow compensated gradient recalled T1-weighted MRI was acquired in 45 RRMS patients. An automated analysis tool was used to calculate brain parenchymal fraction (BPF) and ventricular brain fraction (VF). All patients were assessed with neuropsychological tests focusing on memory and self-rating scales for depression, fatigue and quality of life. Age corrected partial correlations between brain atrophy, motor performance, psychological scales and test scores were calculated. Results BPF correlated moderately (0.3 ≤ r < 0.5) with duration of symptoms and disease, the Expanded Disability Status Scale (EDSS), the upper extremity motor performance, and with mental aspects of quality of life. VF correlated moderately with EDSS, upper and lower extremity motor performance and memory functions. Neither BPF nor VF correlated with fatigue and depression. Results of several cognitive tests correlated moderately with depression and fatigue, the Paced Auditory Serial Addition Test (PASAT) showing the largest correlation. Conclusions Memory performance shows a correlation with relative ventricular size in RRMS patients, indicating the strategic location of the ventricle system along the structures of the limbic system and its vulnerability in MS. The PASAT and several other cognitive tests show moderate correlations with depression and fatigue, arguing for an inter relation between the cognitive functioning and the emotional state of patients. However, this relation is independent of measurable brain atrophy. [ABSTRACT FROM AUTHOR]

In order to investigate activation of the innate immune system in routine toxoplasmosis, T- and B-cell-deficient SCID mice and their co-isogenic immunocompetent C.B-17 counterparts were orally infected with a low-virulent strain of Toxoplasma gondii (DX strain). SCID mice developed a fatal necrotizing toxoplasmosis, whereas CD4+ and CD8 + T cells contributing to inflammatory infiltrates conferred resistance to immunocompetent mice. Significant amounts of interferon-γ (IFN-γ) were detectable in SCID mice. The most likely source for this cytokine is activated natural killer (N K )cells. In comparison to immunocompetent mice I FN-γ levels were reduced in cerebrospinal fluid (CSF) and serum of SCID mice at days 7 and 14 of disease. Similar amounts of turnour necrosis factor (TNF) were detected in both strains of mice. In addition, immunohistochemistry showed major histocompatibility complex (MHC) class II antigen expression on SCID and C.B-17 microglial cells and macrophages demonstrating activation of these cells in both strains. However, the up-regulation of MHC class II antigen on microglia was less pronounced in SC1D mice, presumably due to reduced levels of IFN-γ. Interleukin-6 (IL-6) levels in CSF and serum were elevated in both strains and correlated with systemic and intracerebral disease activity. In conclusion, our results demonstrate activation of macrophages and NK cells as the predominant defence mechanisms of the comprised SCID immune system during toxoplasma infection. This implies a major role for the innate immune system during early stages of toxoplasmosis although T cells are necessary to control the infection efficiently. [ABSTRACT FROM AUTHOR]

Rabbits were immunised repeatedly with bovine brain galactocerebroside. Almost all animals developed overt polyradiculoneuropathy. Circulating IgG antibodies to galactocerebroside in the serum and deposits of IgG in the spinal roots were detectable weeks before definite clinical, morphological, and electrophysiological alterations occurred. The levels of IgG antibody titres to galactocerebroside did not correlate with the severity of the clinical disease and of nerve conduction slowing. Remyelination and a virtually complete recovery of nerve dysfunction occurred although circulating antibodies to galactocerebroside were still present. [ABSTRACT FROM AUTHOR]

Anti-Leu 7 monoclonal antibody (MAB), a marker of natural killer cells, and a human MAB to myelin-associated glycoprotein (MAG) from a patient with a demyelinating neuropathy specifically stained Schmidt-Lanterman incisures, paranodal and periaxonal regions in peripheral nerve myelin by immunocytochemistry on thin plastic sections, while compact myelin was labelled in paraffin-embedded material. Preabsorption studies indicated that the antigen recognised was a MAG epitope shared by MAG and Leu 7. In spinal cord both MABS bound to oligodendrocytes and a subclass of anterior horn cells. Our findings support the hypothesis that shared antigens between the nervous and the immune systems do exist in situ, which may be important in the pathogenesis of demyelinating neuropathies with monoclonal gammopathies. [ABSTRACT FROM AUTHOR]

Within the constraints of operational work supporting humanitarian organizations in their response to the Covid-19 pandemic, we conducted building extraction for Khartoum, Sudan. We extracted approximately 1.2 million dwellings and buildings, using a Mask R-CNN deep learning approach from a Pléiades very high-resolution satellite image with 0.5 m pixel resolution. Starting from an untrained network, we digitized a few hundred samples and iteratively increased the number of samples by validating initial classification results and adding them to the sample collection. We were able to strike a balance between the need for timely information and the accuracy of the result by combining the output from three different models, each aiming at distinctive types of buildings, in a post-processing workflow. We obtained a recall of 0.78, precision of 0.77 and F 1 score of 0.78, and were able to deliver first results in only 10 days after the initial request. The procedure shows the great potential of convolutional neural network frameworks in combination with GIS routines for dwelling extraction even in an operational setting., (© 2021 The Authors. Transactions in GIS published by John Wiley & Sons Ltd.)

This study investigated event-related oscillations associated with a Simon task in 11 Parkinson's disease patients, 11 age-matched, and 11 young participants. During this task, participants respond faster when the relative spatial positions of stimulus and response match (no response conflict exists) than when they do not match (response conflict exists). An increased response conflict (increase in reaction times known as Simon effect) was found in elderly control and Parkinson's patients compared with young participants. Group and condition differences were found in the delta and theta frequency range, which may reflect that Parkinson's patients and matched controls use different cognitive strategies for stimulus-response processing than young controls and neurophysiological correlates of such strategy are deficient in patients compared with age-matched controls.

Purpose: Cognitive disorders are common in MS patients without any generally recommended treatment. Recent brain imaging studies show considerable neuroplasticity for cognitive tasks in MS patients, but also brain atrophy already early in the disease progression. We explored the benefits of a home-based cognitive training program for memory and working memory functions in relapsing-remitting MS patients controlling for whole brain and central brain atrophy as covariates., Methods: Using a single-blinded controlled study design, 42 patients were randomised into a treatment group and a control group. Home based computer training focusing on memory and working memory was started at least 4 weeks after the discontinuation of methylprednisolone treatment and lasted for 6 weeks. Two weeks later the patients were re-investigated for their clinical and cognitive performance. We assessed also quality of life (QoL), depression and fatigue using self-rating scales., Results: Training had no effect on the neurological status and on QoL or fatigue. However, the treatment group showed better verbal learning, long-delay verbal memory performance, and working memory performance. The impact of treatment on long-delay verbal memory performance was independent from the extent of brain atrophy, whereas for the other findings brain atrophy played a significant role., Conclusions: An intensive home-based cognitive training program is suitable to improve the cognitive performance of MS patients. The impact of brain atrophy on rehabilitation outcome may differ for cognitive functions.

The aim of the present study was to investigate alterations in brain oscillatory activity during transient intentional encoding of abstract novel shapes in patients with Parkinson's disease (PD). Combined time-frequency analyses of alpha and theta power revealed a clear dissociation between PD patients (N=10) and age-matched healthy controls (N=10). PD patients used sub-optimal stimulus encoding strategies for subsequent maintenance and recall, whereas the controls mainly used categorization processes. In contrast to controls, PD patients showed significantly less theta increase and upper alpha suppression at frontal locations and significant laterality of early posterior theta and lower-2 alpha oscillations at right posterior locations. These findings suggest that the fronto-striatal circuits participate in visual categorization processes. Furthermore, theta and alpha oscillations appear to be involved in mediating the integration processes in mnemonic networks underlying visual categorization.

In recent years a consensus has been reached about the neuroanatomical substrate of verbal memory, but this state of knowledge has not yet been implemented in clinical practice. One reason for this may be that most of the neuroscientific studies on verbal memory used different neuropsychological instruments and that only a small set of patient groups with the same etiology but different lesion sites were analysed. Returning to three earlier studies, we analyse the possibility to make differential judgements on the verbal memory impairments of four different patient groups by using the California Verbal Learning Test (CVLT). We compare patients with left-sided (n = 16) and right-sided (n = 10) posterior cerebral artery infarcts and patients with infarcts of the left (n = 10) or right (n = 21) frontal lobe, and we integrated data about their retention errors that had not been analysed so far. Our findings reveal significant differences between these patient groups, concerning the quantitative aspects of impairments, and also the profiles of memory errors (recall, interference and perseverations). Our study documents a relation between the site of the lesion and the type of verbal memory impairment, agreeing with some of the most recent neuroscientific findings. Starting from this observation we try to define a neuropsychological pattern of memory impairment which enables differential clinical diagnoses using the CVLT as a memory test.

Early neurological rehabilitation means starting rehabilitation of brain damaged patients already during the acute phase of the trauma or illness. It meanwhile is commonly accepted that early onset of specific neurological rehabilitation interventions will enhance medical improvement and social reintegration potential. On the other hand, the number of treatment places required for adequate early neurological rehabilitation remains a controversial, and as yet unresolved, issue in Germany. In the present study, an evaluation was undertaken for the first time to determine the local demand for early rehabilitation beds in the well-defined region of the federal state of Bremen, based on retrospective analysis of all adults treated for severe brain disease in the major Bremen clinics over a period of 22 months, i.e., between January 1992 and October 1993. A total of 146 early rehabilitation treatments was found, which is equivalent to 80 treatments a year. These results are compared with the figures and recommendations given by Kuratorium ZNS. Also, our findings document the apparent deficits in neurological rehabilitation at the time in the Land Bremen, which undoubtedly jeopardize our daily objectives, the progress and successes achieved in early intensive care.

Factors which determine the pathogenesis and course of Toxoplasma encephalitis are poorly understood. In the present study, the influence of genetic factors in congenic B10 and BALB mice of H-2q, H-2k, and H-2b haplotypes was examined following oral infection with a low-virulence strain of Toxoplasma gondii (DX). There were striking differences among these strains. Whereas B10 mice were highly susceptible, BALB mice had a less severe and more protracted disease. In all animals with a fatal outcome, Toxoplasma encephalitis was the cause of death. Within the two congenic groups, the major histocompatibility complex haplotype had a strong impact on the disease. The H-2k haplotype was associated with early death in B10 mice but with a favorable outcome in BALB mice, whereas the reverse was observed for the H-2q haplotype. These findings indicate that genetically determined factors are critically involved in determining the intracerebral immune response and the course of murine toxoplasmosis. Some of these factors appear to be associated with the major histocompatibility complex haplotype, but significant differences between B10 and BALB mice point to a modulating role of additional genetic loci. Immunohistochemical studies and cytokine analyses of cerebrospinal fluid and serum revealed significant differences in the intracerebral immune response between susceptible and resistant strains. A poor outcome was associated with a large number of intracerebral parasites, significant tissue necrosis, a reduced number of intracerebral CD4+ T cells, low intrathecal tumor necrosis factor levels, and, to a lesser extent, a reduced number of intracerebral CD8+ T cells.