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We examined the effects of whole-body mechanical vibration ( WBV) on indices of motoneuronal excitability at rest and during muscle contraction in healthy humans. Real and sham WBV at 30 Hz had no effect on reflexes measured during muscle contraction. Real WBV at 30 and 50 Hz depressed the H-reflex ∼45%. These depressions diminished across the five inter-bout rest intervals. The depression converted to 27% and 7% facilitation over the 15-min long recovery period following real WBV at 30 and 50 Hz, respectively. The depression, measured during the inter-bout rest, correlated r = 0.48 ( P = 0.007) with the subsequent facilitation, measured during the follow-up. The depression produced by sham vs real WBV was significant but less (23%), recovered faster, and the facilitation was absent in the 15-min long follow-up period. WBV produced time-varying depression followed by facilitation of the H-reflex at rest. A lack of change in volitional wave suggests that WBV did not affect the efferent neural drive. [ABSTRACT FROM AUTHOR]

C. Troakes, T. Hortobágyi, C. Vance, S. Al-Sarraj, B. Rogelj and C. E. Shaw (2013) Neuropathology and Applied Neurobiology 39, 553-561 Transportin 1 colocalization with Fused in Sarcoma (FUS) inclusions is not characteristic for amyotrophic lateral sclerosis- FUS confirming disrupted nuclear import of mutant FUS and distinguishing it from frontotemporal lobar degeneration with FUS inclusions Aims: Transportin 1 (TNPO 1) is an abundant component of the Fused in Sarcoma (FUS)-immunopositive inclusions seen in a subgroup of frontotemporal lobar degeneration (FTLD-FUS). TNPO 1 has been shown to bind to the C-terminal nuclear localizing signal (NLS) of FUS and mediate its nuclear import. Amyotrophic lateral sclerosis (ALS)-linked C-terminal mutants disrupt TNPO 1 binding to the NLS and impair nuclear import in cell culture. If this held true for human ALS then we predicted that FUS inclusions in patients with C-terminal FUS mutations would not colocalize with TNPO 1. Methods: Expression of TNPO 1 and colocalization with FUS was studied in the frontal cortex of FTLD-FUS ( n = 3) and brain and spinal cord of ALS- FUS ( n = 3), ALS- C9orf72 ( n = 3), sporadic ALS ( n = 7) and controls ( n = 7). Expression levels and detergent solubility of TNPO 1 was measured by Western blot. Results: Aggregates of TNPO 1 were abundant and colocalized with FUS inclusions in the cortex of all FTLD-FUS cases. In contrast, no TNPO 1-positive aggregates or FUS colocalization was evident in two-thirds, ALS-FUS cases and was rare in one ALS- FUS case. Nor were they present in C9orf72 or sporadic ALS. No increase in the levels of TNPO 1 was seen in Western blots of spinal cord tissues from all ALS cases compared with controls. Conclusions: These findings confirm that C-terminal FUS mutations prevent TNPO 1 binding to the NLS, inhibiting nuclear import and promoting cytoplasmic aggregation. The presence of TNPO 1 in wild-type FUS aggregates in FTLD-FUS distinguishes the two pathologies and implicates different disease mechanisms. [ABSTRACT FROM AUTHOR]

G. G. Kovacs, A. J. M. Rozemuller, J. C. van Swieten, E. Gelpi, K. Majtenyi, S. Al-Sarraj, C. Troakes, I. Bódi, A. King, T. Hortobágyi, M. M. Esiri, O. Ansorge, G. Giaccone, I. Ferrer, T. Arzberger, N. Bogdanovic, T. Nilsson, I. Leisser, I. Alafuzoff, J. W. Ironside, H. Kretzschmar and H. Budka (2013) Neuropathology and Applied Neurobiology 39, 166-178 Neuropathology of the hippocampus in FTLD-Tau with Pick bodies: a study of the BrainNet Europe Consortium Aims: Frontotemporal lobar degeneration with Pick bodies (Pick's disease) is characterized by the presence of tau immunoreactive spherical structures in the cytoplasm of neurones. In view of confusion about the molecular pathology of Pick's disease, we aimed to evaluate the spectrum of tau pathology and concomitant neurodegeneration-associated protein depositions in the characteristically affected hippocampus. Methods: We evaluated immunoreactivity (IR) for tau (AT8, 3R, 4R), α-synuclein, TDP43, p62, and ubiquitin in the hippocampus, entorhinal and temporal cortex in 66 archival cases diagnosed neuropathologically as Pick's disease. Results: Mean age at death was 68.2 years (range 49-96). Fifty-two (79%) brains showed 3R immunoreactive spherical inclusions in the granule cells of the dentate gyrus. These typical cases presented mainly with the behavioural variant of frontotemporal dementia, followed by progressive aphasia, mixed syndromes or early memory disturbance. α-Synuclein IR was seen only in occasional spherical tau-positive inclusions, TDP-43 IR was absent, and 4R IR was present only as neurofibrillary tangles in pyramidal neurones. Aβ IR was observed in 16 cases; however, the overall level of Alzheimer's disease-related alterations was mainly low or intermediate ( n = 3). Furthermore, we identified six cases with unclassifiable tauopathy. Conclusions: (i) Pick's disease may occur also in elderly patients and is characterized by a relatively uniform pathology with 3R tau inclusions particularly in the granule cells of dentate gyrus; (ii) even minor deviation from these morphological criteria suggests a different disorder; and (iii) immunohistological revision of archival cases expands the spectrum of tauopathies that require further classification. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about desmoplastic ganglioglioma with meninggiomatous and myofibroblastic components presenting with epilepsy.

Immunohistochemistry staining for β-amyloid precursor protein (β-APP) is a sensitive method to detect early axonal damage in traumatic brain injury, which was previously estimated to be of minimum 60–90 min after head injury. We present seven cases of well-documented posttraumatic survival of 35–60 min where β-APP detects early axonal damage. Cases were selected from routine work where documentation about survival is judged to be accurate. These are divided into three groups: group 1: severe head injury ( n = 7) with documented survival between 35 and 60 min. Group 2: severe head injury ( n = 4) with documented survival of less than 30 min. Group 3: cases ( n = 4) where death was not due to head injury but survival is documented between 45 and 109 min. The brains were fixed in formalin for 4 weeks and six regions (frontal lobe with anterior corpus callosum, parietal lobe with deep white matter, basal ganglia with posterior limb of internal capsule, cerebellum with white matter and middle cerebellar peduncle and pons with basis pontis and superior cerebellar peduncle) were sampled. All blocks were stained for haematoxylin and eosin and β-APP and selected ones for CD68, using antigen retrieval method. In group 1 sections revealed β-APP immunoreactivity in forms of small globules and granules and occasionally as thin and short filaments. These were detected in the pons, corpus callosum, internal capsule and cerebral white matter, with some variation in localization and intensity. In groups 2 and 3 all the sections were negative for β-APP staining. None of the cases showed evidence of severe brain swelling, increased intracranial pressure, ischaemia or infection. Using the antigen retrieval method, β-APP immunohistochemistry can detect axonal damage within 35 min after severe head injury. These results may have an implication in the consideration of minimal survival time after traumatic head injury in medico-legal practice. [ABSTRACT FROM AUTHOR]

The article presents a study on adult cerebellar liponeurocytoma with predominant pilocytic pattern and myoid differentiation. It is noted that lipidization is rare in neuroepithelial neoplasms. Cerebellar liponeurocytoma is determined as one of the new entities incorporated in the recent classification of tumour of the nervous system.

Introduction: Aneurysmal malformation of the vein of Galen (AVG) is caused by an arteriovenous fistula (AVF) between the basal arteries and deep venous sinuses of the brain. Congenital forms of AVG are potentially fatal, leading to a left-to-right shunt and cardiomegaly, and the death is most commonly as a result of cardiac failure. We present a case with an AVF of brain with an ASD. Material and methods: A mature male baby born at gestational week 38 was admitted to PICU with tachydyspnoe 4 h after birth. Ultrasound (US) and computed tomography scans of the brain detected a large bilateral AVF with dilated basal arteries and venous sinuses (sinus petrosus, sinus confluens, sinus transvs. and sagittal inferior sinus), hydrocephalus and brain atrophy. Cardiac US showed right ventricular hypertrophy, persistent ductus Botall and ASD. The patient died of cardiac failure 6 days after birth. Results: Autopsy examination of the brain showed dilatation of the vein of Galen and venous sinuses, a large conglomerate of dilated blood vessels in the midline and left occipital lobe, oedema and hydrocephalus. Examination of the heart confirmed Us findings and showed an ostium secundum ASD. Histologically, the occipital mass revealed features of an AVF, consistent with AVG. Chronic ischaemic lesions with ferruginated neurons were also present. Conclusions: The presence of chronic hypoxic changes in the brain suggests intrauterine damage as a result of a congenital AVF. The left-to-right shunt, in addition to causing cardiomegaly, may also have interfered with the development of the atrial septum, leading to an ostium secundum ASD, aggravating the clinical course. [ABSTRACT FROM AUTHOR]

Unilateral muscle contractions are often accompanied by the activation of the ipsilateral hemisphere, producing associated activity (AA) in the contralateral homologous muscles. However, the functional role of AA is not fully understood. We determined the effects of voluntary suppression of AA in the first dorsal interosseous (FDI), on force steadiness during a constant force isometric contraction of the contralateral FDI. Participants (n = 17, 25.5 years) performed two trials of isometric FDI contractions as steadily as possible. In Trial 1, they did not receive feedback or explicit instructions for suppressing the AA in the contralateral homologous FDI. In Trial 2, participants received feedback and were asked to voluntarily suppress the AA in the contralateral nontarget FDI. During both trials, corticospinal excitability and motor cortical inhibition were measured. The results show that participants effectively suppressed the AA in the nontarget contralateral FDI (-71%), which correlated with reductions in corticospinal excitability (-57%), and the suppression was also accompanied by increases in inhibition (27%) in the ipsilateral motor cortex. The suppression of AA impaired force steadiness, but the decrease in force steadiness did not correlate with the magnitude of suppression. The results show that voluntary suppression of AA decreases force steadiness in the active hand. However, due to the lack of association between suppression and decreased steadiness, we interpret these data to mean that specific elements of the ipsilateral brain activation producing AA in younger adults are neither contributing nor detrimental to unilateral motor control during a steady isometric contraction., (© 2021 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Unilateral lengthening contractions provide a greater stimulus for neuromuscular adaptation than shortening contractions in the active and non-active contralateral homologous muscle, although little is known of the potential mechanism. Here we examined the possibility that corticospinal and spinal excitability vary in a contraction-specific manner in the relaxed right flexor carpi radialis (FCR) when humans perform unilateral lengthening and shortening contractions of the left wrist flexors at the same absolute force. Corticospinal excitability in the relaxed right FCR increased more during lengthening than shortening at 80% and 100% of maximum voluntary contraction (MVC). Short-interval intracortical inhibition diminished during shortening contractions, and it became nearly abolished during lengthening. Intracortical facilitation lessened during shortening but increased during lengthening. Interhemispheric inhibition to the 'non-active' motor cortex diminished during shortening, and became nearly abolished during lengthening at 90% MVC. The amplitude of the Hoffman reflex in the relaxed right FCR decreased during and remained depressed for 20 s after lengthening and shortening of the left wrist flexors. We discuss the possibility that instead of the increased afferent input, differences in the descending motor command and activation of brain areas that link function of the motor cortices during muscle lengthening vs. shortening may cause the contraction-specific modulation of ipsilateral motor cortical output. In conclusion, ipsilateral motor cortex responses to transcranial magnetic stimulation are contraction-specific; unilateral lengthening and shortening contractions reduced contralateral spinal excitability, but uniquely modulated ipsilateral corticospinal excitability and the networks involved in intracortical and interhemispheric connections, which may have clinical implications., (© 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.)