Prevalence, Characteristics, and Outcomes of COVID-19-Associated Acute Myocarditis.

BACKGROUND: Acute myocarditis (AM) is thought to be a rare cardiovascular complication of COVID-19, although minimal data are available beyond case reports. We aim to report the prevalence, baseline characteristics, in-hospital management, and outcomes for patients with COVID-19-associated AM on the basis of a retrospective cohort from 23 hospitals in the United States and Europe. METHODS: A total of 112 patients with suspected AM from 56 963 hospitalized patients with COVID-19 were evaluated between February 1, 2020, and April 30, 2021. Inclusion criteria were hospitalization for COVID-19 and a diagnosis of AM on the basis of endomyocardial biopsy or increased troponin level plus typical signs of AM on cardiac magnetic resonance imaging. We identified 97 patients with possible AM, and among them, 54 patients with definite/probable AM supported by endomyocardial biopsy in 17 (31.5%) patients or magnetic resonance imaging in 50 (92.6%). We analyzed patient characteristics, treatments, and outcomes among all COVID-19-associated AM. RESULTS: AM prevalence among hospitalized patients with COVID-19 was 2.4 per 1000 hospitalizations considering definite/probable and 4.1 per 1000 considering also possible AM. The median age of definite/probable cases was 38 years, and 38.9% were female. On admission, chest pain and dyspnea were the most frequent symptoms (55.5% and 53.7%, respectively). Thirty-one cases (57.4%) occurred in the absence of COVID-19-associated pneumonia. Twenty-one (38.9%) had a fulminant presentation requiring inotropic support or temporary mechanical circulatory support. The composite of in-hospital mortality or temporary mechanical circulatory support occurred in 20.4%. At 120 days, estimated mortality was 6.6%, 15.1% in patients with associated pneumonia versus 0% in patients without pneumonia (P=0.044). During hospitalization, left ventricular ejection fraction, assessed by echocardiography, improved from a median of 40% on admission to 55% at discharge (n=47; P<0.0001) similarly in patients with or without pneumonia. Corticosteroids were frequently administered (55.5%). CONCLUSIONS: AM occurrence is estimated between 2.4 and 4.1 out of 1000 patients hospitalized for COVID-19. The majority of AM occurs in the absence of pneumonia and is often complicated by hemodynamic instability. AM is a rare complication in patients hospitalized for COVID-19, with an outcome that differs on the basis of the presence of concomitant pneumonia.

Granular cell tumor of the neurohypophysis presenting as a third ventricle mass.

Granular cell tumors of the neurohypophysis (GCT) are rare benign neoplasms belonging, along with pituicytoma and spindle cell oncocytoma, to the family of TTF1-positive low-grade neoplasms of the posterior pituitary gland. GCT usually present as a solid sellar mass, slowly growing and causing compressive symptoms over time, occasionally with suprasellar extension. They comprise polygonal monomorphous cells with abundant granular cytoplasm, which is ultrastructurally filled with lysosomes. Here we report the case of a GCT presenting as a third ventricle mass, radiologically mimicking chordoid glioma, with aberrant expression of GFAP and Annexin-A, which lends itself as an example of an integrated diagnostic approach to sellar/suprasellar and third ventricle masses.

Dendritic pathology, spine loss and synaptic reorganization in human cortex from epilepsy patients.

Neuronal dendritic arborizations and dendritic spines are crucial for a normal synaptic transmission and may be critically involved in the pathophysiology of epilepsy. Alterations in dendritic morphology and spine loss mainly in hippocampal neurons have been reported both in epilepsy animal models and in human brain tissues from patients with epilepsy. However, it is still unclear whether these dendritic abnormalities relate to the cause of epilepsy or are generated by seizure recurrence. We investigated fine neuronal structures at the level of dendritic and spine organization using Golgi impregnation, and analysed synaptic networks with immunohistochemical markers of glutamatergic (vGLUT1) and GABAergic (vGAT) axon terminals in human cerebral cortices derived from epilepsy surgery. Specimens were obtained from 28 patients with different neuropathologically defined aetiologies: type Ia and type II focal cortical dysplasia, cryptogenic (no lesion) and temporal lobe epilepsy with hippocampal sclerosis. Autoptic tissues were used for comparison. Three-dimensional reconstructions of Golgi-impregnated neurons revealed severe dendritic reshaping and spine alteration in the core of the type II focal cortical dysplasia. Dysmorphic neurons showed increased dendritic complexity, reduction of dendritic spines and occasional filopodia-like protrusions emerging from the soma. Surprisingly, the intermingled normal-looking pyramidal neurons also showed severe spine loss and simplified dendritic arborization. No changes were observed outside the dysplasia (perilesional tissue) or in neocortical postsurgical tissue obtained in the other patient groups. Immunoreactivities of vGLUT1 and vGAT showed synaptic reorganization in the core of type II dysplasia characterized by the presence of abnormal perisomatic baskets around dysmorphic neurons, in particular those with filopodia-like protrusions, and changes in vGLUT1/vGAT expression. Ultrastructural data in type II dysplasia highlighted the presence of altered neuropil engulfed by glial processes. Our data indicate that the fine morphological aspect of neurons and dendritic spines are normal in epileptogenic neocortex, with the exception of type II dysplastic lesions. The findings suggest that the mechanisms leading to this severe form of cortical malformation interfere with the normal dendritic arborization and synaptic network organization. The data argue against the concept that long-lasting epilepsy and seizure recurrence per se unavoidably produce a dendritic pathology.

pCREB expression in human tissues from epilepsy surgery.

OBJECTIVE: Activity-dependent changes have been reported in animal models and in human epileptic specimens and could potentially be used as tissue biomarkers to evaluate the propensity of a tissue to generate seizure activity. In this context, cAMP-response element binding protein (CREB) activation was specifically reported in human epileptic foci and related mainly to interictal spike activity. To get further insights into CREB activation in human epilepsy, we analyzed pCREB expression on brain tissue samples from patients who underwent surgery for drug-resistant focal epilepsy, correlating this expression with intracranial stereo-electroencephalography (SEEG) recording in a subgroup. METHODS: Neocortical specimens from patients with neuropathological diagnosis of no lesion (cryptogenic), malformations of cortical development,mainly type II focal cortical dysplasia (FCD), and hippocampi with and without hippocampal sclerosis have been analyzed by immunohistochemistry. Peritumoral cortex from non-epileptic patients and autoptic samples were used as controls, whereas rat brains were used to test possible loss of pCREB antigenicity due to fixation procedures and postmortem delay. RESULTS: pCREB was consistently expressed in layer II neuronal nuclei in regions with normal cortical lamination both in epileptic and non-epileptic surgical tissues. In patients with SEEG recordings, this anatomical pattern was unrelated to the presence of interictal spike activity. Conversely, in the core of type II FCD, as well as in other developmental malformations, pCREB was scattered without any laminar specificity. Furthermore, quantitative data did not reveal significant differences between epileptic and non-epileptic tissues, except for an increased immunoreactivity in the core of type IIB FCD lesion related mainly to reactive glial and balloon cells. SIGNIFICANCE: The present data argue against the reliability of pCREB immunohistochemistry as a marker of epileptic focus but underscores its layer-related expression, suggesting a potential application in the study of malformations of cortical development, a wide range of diseases arising from perturbations of normal brain development.

Type II focal cortical dysplasia: Ex vivo 7T magnetic resonance imaging abnormalities and histopathological comparisons.

OBJECTIVE: In the present report, the correlations between ex vivo high-resolution imaging and specific histological and ultrastructural patterns in type II focal cortical dysplasia (FCD) have been studied to explain the differences in the magnetic resonance imaging (MRI) detection of dysplasia and to contribute to the presurgical imaging evaluation of this pathology. METHODS: Surgical specimens from 13 patients with FCD IIa/b were submitted to 7T MRI scanning, and then analyzed histologically and ultrastructurally to compare the results with the MRI findings. Region of interest (ROI)-based measures on T2-weighted images (T2wi) were quantitatively evaluated in the lesion and in adjacent perilesional gray and white matter. RESULTS: Matched histological sections and 7T T2wi showed that the core of the lesion was characterized by patchy aggregates of abnormal cells and fiber disorganization related to inhomogeneity of intracortical signal intensity. The quantitative approach on T2wi can help to distinguish the lesions and perilesional areas even in a clinical MRI-negative case. The ultrastructural study showed that the strong signal hyperintensity in the white matter of FCD IIb was related to a dysmyelination process associated with severe fiber loss and abnormal cells. Less severe histopathological features were found in FCD IIa, thus reflecting their less evident MRI alterations. INTERPRETATION: We suggest that white matter abnormalities in type IIb FCD are due to defects of the myelination processes and maturation, impaired by the presence of balloon cells. To reveal the presence and the border of type II cortical dysplasia on MRI, a quantitative ROI-based analysis (coefficient of variation) is also proposed.

Safe Energy Source in Battery-operated Toys for Children.

OBJECTIVES: Serious and even fatal consequences of disk batteries ingestion in children are well known. Among other applications, disk batteries are used to power small toys, from which they can be unexpectedly extracted and swallowed. METHODS: We tested a new cell intended for little toys (green cell [GC]), after 6 and 12 hours of in vitro close contact with esophageal swine mucosa. The GC was compared with lithium and silver button batteries under the same experimental conditions. RESULTS: Tissues in contact with the GC did not show pH variations nor histological alterations after 6 and 12 hours. In such conditions, statistically significant differences were found between the GC and the lithium and silver batteries. CONCLUSIONS: So far, multidisciplinary medical effort has been driven to both emergency approach and subsequent operative strategies in children with ingested batteries. Our trial demonstrates the possibility to primarily prevent battery-induced damages by designing new-generation safe cells with no tissue toxicity to power little toys intended for children.

Different parvalbumin and GABA expression in human epileptogenic focal cortical dysplasia.

OBJECTIVE: Several studies have reported that inhibitory networks are altered in dysplastic tissue obtained from epilepsy surgery specimens. A consistent decrease in the number of inhibitory interneuronal subpopulation that expresses parvalbumin (PV) was reported in postsurgical tissue from patients with focal cortical dysplasia (FCD). We tested if the decrease in PV protein expression observed in epileptic tissue corresponds to a parallel impairment in the γ-aminobutyric acid (GABA)ergic compartment. METHODS: We analyzed postsurgical tissue from 30 surgically treated patients who underwent surgery for intractable epilepsy including 26 patients with FCD (types I, II, and III) and 4 patients without any microscopic visible lesion (cryptogenic) as controls. Serial sections were processed using in situ hybridization with GAD-65 and GAD-67 probes and immunocytochemistry with antibody against PV. The density of inhibitory PV-immunoreactive interneurons in relation to GABAergic cells was estimated in controls and in all different pathologic groups by using a two- and three-dimensional (2D and 3D) cell-counting technique. Field fraction and line profile analyses were added to estimate immunostaining proportion and distribution of PV signal generated in gray matter. RESULTS: A reduction of PV-positive cells and PV-immunoreactivity was observed exclusively in FCD type I/III specimens compared with cryptogenic tissue from control patients with a poor postsurgical outcome. In FCD type II, a profound rearrangement in the cortical distribution of PV immunoreactivity was observed, without a quantitative reduction of the number of neurons and terminals. In situ hybridization did not reveal significant variations of GAD expression in any FCD subtype. SIGNIFICANCE: Our study suggests a preservation of inhibitory networks in FCD postsurgical tissue, demonstrated by a substantial normal count of GABAergic neurons. A selective PV expression impairment is demonstrated in FCD type I and III and an abnormal, but not reduced, distribution of PV cells and terminals is confirmed in type II FCD. Possible functional consequences are discussed.

Short- and long-term surgical outcomes of temporal lobe epilepsy associated with hippocampal sclerosis: Relationships with neuropathology.

OBJECTIVE: Hippocampal sclerosis (HS) is the most frequent neuropathologic finding in patients undergoing surgery for intractable temporal lobe epilepsy (TLE). The International League Against Epilepsy (ILAE) has recently proposed a new classification of HS based on specific patterns of cell loss. The aim of this study was to investigate the relationships between HS types, their etiologic factors, and the short- and long-term postsurgical outcomes of patients undergoing surgery because of drug-resistant TLE with HS. METHODS: Two hundred thirteen patients with a neuropathologic diagnosis of HS and a minimum follow-up of 2 years were divided on the basis of their ILAE HS type and further classified into: (1) isolated HS, (2) HS associated with focal cortical dysplasia (FCD IIIa), or (3) HS associated with other lesions. Their clinical and neuropathologic data were correlated with their Engel class postsurgical outcomes. RESULTS: The main findings were the following: (1) HS type 1 was associated with a longer duration of epilepsy; (2) >80% of the patients had an Engel class I short- and long-term outcomes, regardless of HS type and associated pathology; (3) short- and long-term postsurgical outcomes were less satisfactory in the patients who were completely seizure-free (Engel class Ia), and patients with HS type 2 had better long-term seizure outcomes than those with type 1; (4) the concomitant presence of FCD contributed to a worse outcome, regardless of HS type; and (5) a shorter duration of epilepsy significantly correlated with an Engel class Ia outcome. SIGNIFICANCE: These data suggest that HS type and associated pathologies may predict the risk of recurrence, but other variables such as the duration of epilepsy need to be considered. A common neuropathologic classification system may help to identify preoperative predictive factors and improve the selection of patients who may benefit from epilepsy surgery.

7T MRI in focal epilepsy with unrevealing conventional field strength imaging.

OBJECTIVE: To assess the diagnostic yield of 7T magnetic resonance imaging (MRI) in detecting and characterizing structural lesions in patients with intractable focal epilepsy and unrevealing conventional (1.5 or 3T) MRI. METHODS: We conducted an observational clinical imaging study on 21 patients (17 adults and 4 children) with intractable focal epilepsy, exhibiting clinical and electroencephalographic features consistent with a single seizure-onset zone (SOZ) and unrevealing conventional MRI. Patients were enrolled at two tertiary epilepsy surgery centers and imaged at 7T, including whole brain (three-dimensional [3D] T1 -weighted [T1W] fast-spoiled gradient echo (FSPGR), 3D susceptibility-weighted angiography [SWAN], 3D fluid-attenuated inversion recovery [FLAIR]) and targeted imaging (2D T2*-weighted dual-echo gradient-recalled echo [GRE] and 2D gray-white matter tissue border enhancement [TBE] fast spin echo inversion recovery [FSE-IR]). MRI studies at 1.5 or 3T deemed unrevealing at the referral center were reviewed by three experts in epilepsy imaging. Reviewers were provided information regarding the suspected localization of the SOZ. The same team subsequently reviewed 7T images. Agreement in imaging interpretation was reached through consensus-based discussions based on visual identification of structural abnormalities and their likely correlation with clinical and electrographic data. RESULTS: 7T MRI revealed structural lesions in 6 (29%) of 21 patients. The diagnostic gain in detection was obtained using GRE and FLAIR images. Four of the six patients with abnormal 7T underwent epilepsy surgery. Histopathology revealed focal cortical dysplasia (FCD) in all. In the remaining 15 patients (71%), 7T MRI remained unrevealing; 4 of the patients underwent epilepsy surgery and histopathologic evaluation revealed gliosis. SIGNIFICANCE: 7T MRI improves detection of epileptogenic FCD that is not visible at conventional field strengths. A dedicated protocol including whole brain FLAIR and GRE images at 7T targeted at the suspected SOZ increases the diagnostic yield.

Linking acetylated α-Tubulin redistribution to α-Synuclein pathology in brain of Parkinson's disease patients.

Highly specialized microtubules in neurons are crucial to both health and disease of the nervous system, and their properties are strictly regulated by different post-translational modifications, including α-Tubulin acetylation. An imbalance in the levels of acetylated α-Tubulin has been reported in experimental models of Parkinson's disease (PD) whereas pharmacological or genetic modulation that leads to increased acetylated α-Tubulin successfully rescues axonal transport defects and inhibits α-Synuclein aggregation. However, the role of acetylation of α-Tubulin in the human nervous system is largely unknown as most studies are based on in vitro evidence. To capture the complexity of the pathological processes in vivo, we analysed post-mortem human brain of PD patients and control subjects. In the brain of PD patients at Braak stage 6, we found a redistribution of acetylated α-Tubulin, which accumulates in the neuronal cell bodies in subcortical structures but not in the cerebral cortex, and decreases in the axonal compartment, both in putamen bundles of fibres and in sudomotor fibres. High-resolution and 3D reconstruction analysis linked acetylated α-Tubulin redistribution to α-Synuclein oligomerization and to phosphorylated Ser 129 α-Synuclein, leading us to propose a model for Lewy body (LB) formation. Finally, in post-mortem human brain, we observed threadlike structures, resembling tunnelling nanotubes that contain α-Synuclein oligomers and are associated with acetylated α-Tubulin enriched neurons. In conclusion, we support the role of acetylated α-Tubulin in PD pathogenesis and LB formation.

Long-duration epilepsy affects cell morphology and glutamatergic synapses in type IIB focal cortical dysplasia.

To investigate hypothesized effects of severe epilepsy on malformed cortex, we analyzed surgical samples from eight patients with type IIB focal cortical dysplasia (FCD) in comparison with samples from nine non-dysplastic controls. We investigated, using stereological quantification methods, where appropriate, dysplastic neurons, neuronal density, balloon cells, glia, glutamatergic synaptic input, and the expression of N-methyl-D-aspartate (NMDA) receptor subunits and associated membrane-associated guanylate kinase (MAGUK). In all FCD patients, the dysplastic areas giving rise to epileptic discharges were characterized by larger dysmorphic neurons, reduced neuronal density, and increased glutamatergic inputs, compared to adjacent areas with normal cytology. The duration of epilepsy was found to correlate directly (a) with dysmorphic neuron size, (b) reduced neuronal cell density, and (c) extent of reactive gliosis in epileptogenic/dysplastic areas. Consistent with increased glutamatergic input, western blot revealed that NMDA regulatory subunits and related MAGUK proteins were up-regulated in epileptogenic/dysplastic areas of all FCD patients examined. Taken together, these results support the hypothesis that epilepsy itself alters morphology-and probably also function-in the malformed epileptic brain. They also suggest that glutamate/NMDA/MAGUK dysregulation might be the intracellular trigger that modifies brain morphology and induces cell death.

Epilepsy surgery of focal cortical dysplasia-associated tumors.

The goal of the present study was to evaluate the clinical characteristics and postoperative seizure outcome of epileptogenic tumors associated with focal cortical dysplasias (FCDs) compared to both solitary FCD type I and solitary tumors. Particular attention is given to FCD type IIIb (tumors associated with FCD type I), which have been recently classified as a separate entity. We retrospectively reviewed the clinical charts of 1,109 patients who were operated on for drug-resistant focal epilepsy, including 492 patients with a histologic diagnosis of solitary FCD I and II (83 and 157 cases, respectively), solitary tumors (179 cases), and FCD-associated tumors (73 cases, 58 of which met the criteria of FCD IIIb of the new International League Against Epilepsy [ILAE] classification). The different subgroups were evaluated for clinical characteristics and postoperative surgical outcome. Clinical variables and postoperative seizure outcome of patients with coexisting tumor and FCDs (FCD IIIb and tumor associated FCD II) were similar to those of patients with a solitary tumor and differed significantly from patients with solitary FCDs. Nevertheless, tumors associated with FCDs are characterized by a striking male predominance and a higher seizure frequency as compared to solitary tumors. Patients with drug-resistant focal epilepsy secondary to a solitary tumor or with a tumor-associated FCD have similar basic clinical presentation and postoperative seizure outcome. Nevertheless, the epileptogenic contribution of the associated FCDs can be crucial, and it needs to be adequately assessed. The impact of FCD on tumor-related epilepsy deserves future research in order to optimize the surgical strategies aimed at seizure relief.

Focal cortical dysplasia type IIa and IIb: MRI aspects in 118 cases proven by histopathology.

INTRODUCTION: This study aims to review the magnetic resonance imaging (MRI) aspects of a large series of patients with focal cortical dysplasia type II (FCD II) and attempt to identify distinctive features in the two histopathological subtypes IIa and IIb. METHODS: We retrospectively reviewed the MRI scans of 118 patients with histological proven FCD IIa (n = 37) or IIb (n = 81) who were surgically treated for intractable epilepsy. RESULTS: MRI was abnormal in 93 patients (79 %) and unremarkable in 25 (21 %). A dysplastic lesion was identified in 90 cases (97 %) and classified as FCD II in 83 and FCD non-II in seven cases. In three cases, the MRI diagnosis was other than FCD. There was a significant association between the presence of cortical thickening (p = 0.002) and the "transmantle sign" (p < 0.001) and a correct MRI diagnosis of FCD II. MRI positivity was more frequent in the patients with FCD IIb than in those with FCD IIa (91 % vs. 51 %), and the detection rate of FCD II was also better in the patients with type IIb (88 % vs. 32 %). The transmantle sign was significantly more frequent in the IIb subgroup (p = 0.003). CONCLUSIONS: The rates of abnormal MRI results and correct MRI diagnoses of FCD II were significantly higher in the IIb subgroup. Although other MRI stigmata may contribute to the diagnosis, the only significant correlation was between the transmantle sign and FCD IIb.

Electroclinical, MRI and surgical outcomes in 100 epileptic patients with type II FCD.

Focal cortical dysplasias (FCDs) are highly epileptogenic malformations associated with drug-resistant epilepsy, susceptible to surgical treatment. Among the different types of FCD, the type II includes two subgroups based on the absence (IIa) or presence (IIb) of balloon cells. The aim of this retrospective study was to investigate possible differences in electroclinical presentations and surgical outcomes between the two subgroups in 100 consecutive surgically treated patients with type II FCDs. All patients underwent a comprehensive presurgical assessment including stereo-EEG (SEEG) when necessary. No significant differences in gender, age at epilepsy onset, duration of epilepsy, age at surgery or seizure frequency were found between the two subgroups. Patients with type IIb FCD frequently showed sleep-related epilepsy. Their peculiar electrographic pattern was characterised by localised rhythmic or pseudo-rhythmic spikes or polyspikes ("brushes") enhanced during non-REM sleep and also associated with well-localised, brief, low-voltage fast activity. The incidence and frequency of short bursts of fast discharges, interrupted by activity suppression, increased during slow-wave sleep and often recurred pseudo-periodically. The occurrence of "brushes", present in 76% of the patients with type IIb FCD, was significantly associated (p<0.001) with the presence of balloon cells. We discuss the possible pathogenetic mechanisms underlying this activity. MRI diagnosis of type II FCD was made in 93% of the patients with balloon cells (BCs), suggesting that the presence of balloon cells might be, at least partially, responsible for the MRI features. Patients had very good postsurgical outcomes (83% in Engel class I) even after a long period of follow-up.

Role of Nuclear Lamin A/C in the Regulation of Nav1.5 Channel and Microtubules: Lesson From the Pathogenic Lamin A/C Variant Q517X.

In this work, we studied an lmna nonsense mutation encoding for the C-terminally truncated Lamin A/C (LMNA) variant Q517X, which was described in patients affected by a severe arrhythmogenic cardiomyopathy with history of sudden death. We found that LMNA Q517X stably expressed in HL-1 cardiomyocytes abnormally aggregates at the nuclear envelope and within the nucleoplasm. Whole-cell patch clamp experiments showed that LMNA Q517X-expressing cardiomyocytes generated action potentials with reduced amplitude, overshoot, upstroke velocity and diastolic potential compared with LMNA WT-expressing cardiomyocytes. Moreover, the unique features of these cardiomyocytes were 1) hyper-polymerized tubulin network, 2) upregulated acetylated α-tubulin, and 3) cell surface Nav1.5 downregulation. These findings pointed the light on the role of tubulin and Nav1.5 channel in the abnormal electrical properties of LMNA Q517X-expressing cardiomyocytes. When expressed in HEK293 with Nav1.5 and its ß1 subunit, LMNA Q517X reduced the peak Na+ current (INa) up to 63% with a shift toward positive potentials in the activation curve of the channel. Of note, both AP properties in cardiomyocytes and Nav1.5 kinetics in HEK293 cells were rescued in LMNA Q517X-expressing cells upon treatment with colchicine, an FDA-approved inhibitor of tubulin assembly. In conclusion, LMNA Q517X expression is associated with hyper-polymerization and hyper-acetylation of tubulin network with concomitant downregulation of Nav1.5 cell expression and activity, thus revealing 1) new mechanisms by which LMNA may regulate channels at the cell surface in cardiomyocytes and 2) new pathomechanisms and therapeutic targets in cardiac laminopathies.

Astrocytes expressing Vitamin D-activating enzyme identify Parkinson's disease.

INTRODUCTION: Astrocytes are involved in Parkinson's disease (PD) where they could contribute to α-Synuclein pathology but also to neuroprotection via α-Synuclein clearance. The molecular signature underlying their dual role is still elusive. Given that vitamin D has been recently suggested to be protective in neurodegeneration, the aim of our study was to investigate astrocyte and neuron vitamin D pathway alterations and their correlation with α-Synuclein aggregates (ie, oligomers and fibrils) in human brain obtained from PD patients. METHODS: The expression of vitamin D pathway components CYP27B1, CYP24A1, and VDR was examined in brains obtained from PD patients (Braak stage 6; n = 9) and control subjects (n = 4). We also exploited proximity ligation assay to identified toxic α-Synuclein oligomers in human astrocytes. RESULTS: We found that vitamin D-activating enzyme CYP27B1 identified a subpopulation of astrocytes exclusively in PD patients. CYP27B1 positive astrocytes could display neuroprotective features as they sequester α-Synuclein oligomers and are associated with Lewy body negative neurons. CONCLUSION: The presence of CYP27B1 astrocytes distinguishes PD patients and suggests their contribution to protect neurons and to ameliorate neuropathological traits.

Type I focal cortical dysplasia: surgical outcome is related to histopathology.

Pre-surgical and post-surgical data were examined and compared from 215 consecutive patients undergoing surgery for intractable epilepsy. Patients were selected on the basis of a proven histopathological diagnosis of type I focal cortical dysplasia (FCD I), alone or associated with other lesions. The patients were divided into five sub-groups: i) 66 with isolated FCD I, ii) 76 with FCD I and hippocampal sclerosis, iii) 49 with FCD I and tumours, iv) 16 with FCD I and other malformations of cortical development and v) eight with FCD I and anoxic-ischaemic or inflammatory diseases. The duration of epilepsy was greatest in patients with FCD I associated with hippocampal sclerosis, and those with isolated FCD I showed the highest seizure frequency at the time of surgery. Hippocampal sclerosis and tumours were the most frequent pathological lesions associated with FCD I in temporal lobe epilepsy. Febrile seizures significantly correlated with the presence of hippocampal sclerosis and FCD I. Isolated FCD I was observed in 31% of the patients, characterized by frequent seizures, negative magnetic resonance imaging, and frequent frontal or multilobar involvement. In comparison to patients with FCD I associated with hippocampal sclerosis, MCD or tumours, the patients with isolated FCD I had a worse post-surgical outcome (46% in class I). Our findings indicate that there is a high incidence of FCD I associated with other apparently distinct pathologies, particularly those affecting the temporal lobe, and highlight the need for a comprehensive clinicopathological approach for the classification of FCD I.

Phospho-HDAC6 Gathers Into Protein Aggregates in Parkinson's Disease and Atypical Parkinsonisms.

HDAC6 is a unique histone deacetylase that targets cytoplasmic non-histone proteins and has a specific ubiquitin-binding activity. Both of these activities are required for HDAC6-mediated formation of aggresomes, which contain misfolded proteins that will ultimately be degraded via autophagy. HDAC6 deacetylase activity is increased following phosphorylation on serine 22 (phospho-HDAC6). In human, HDAC6 localizes in neuronal Lewy bodies in Parkinson's disease (PD) and in oligodendrocytic Papp-Lantos bodies in multiple system atrophy (MSA). However, the expression of phospho-HDAC6 in post-mortem human brains is currently unexplored. Here, we evaluate and compare the distribution of HDAC6 and its phosphorylated form in human brains obtained from patients affected by three forms of parkinsonism: two synucleinopathies (PD and MSA) and a tauopathy (progressive supranuclear palsy, PSP). We find that both HDAC6 and its phosphorylated form localize with pathological protein aggregates, including α-synuclein-positive Lewy bodies in PD and Papp-Lantos bodies in MSA, and phospho-tau-positive neurofibrillary tangles in PSP. We further find a direct interaction of HDAC6 with α-synuclein with proximity ligation assay (PLA) in neuronal cell of PD patients. Taken together, our findings suggest that both HDAC6 and phospho-HDAC6 regulate the homeostasis of intra-neuronal proteins in parkinsonism.

Accurate Detection of Hot-Spot MTOR Somatic Mutations in Archival Surgical Specimens of Focal Cortical Dysplasia by Molecular Inversion Probes.

BACKGROUND: Formalin-fixed, paraffin-embedded brain specimens are a potentially rich resource to identify somatic variants, but their DNA is characterised by low yield and extensive degradation, and matched peripheral samples are usually unavailable for analysis. METHODS: We designed single-molecule molecular inversion probes to target 18 MTOR somatic mutational hot-spots in unmatched, histologically proven focal cortical dysplasias from formalin-fixed, paraffin-embedded tissues of 50 patients. RESULTS: We achieved adequate DNA and sequencing quality in 28 focal cortical dysplasias, mostly extracted within 2 years from fixation, showing a statistically significant effect of time from fixation as a major determinant for successful genetic analysis. We identified and validated seven encompassing hot-spot residues (found in 14% of all patients and in 25% of those sequenced and analysed). The allele fraction had a range of 2-5% and variants were absent in available neighbouring non-focal cortical dysplasia specimens. We computed an alternate allele threshold for calling true variants, based on an experiment-wise mismatch count distribution, well predicting call reliability. CONCLUSIONS: Single-molecule molecular inversion probes are experimentally simple, cost effective and scalable, accurately detecting clinically relevant somatic variants in challenging brain formalin-fixed, paraffin-embedded tissues.

Nodular heterotopia: a neuropathological study of 24 patients undergoing surgery for drug-resistant epilepsy.

PURPOSE: Despite the availability of detailed electroclinical and imaging data, only a few neuropathological studies of nodular heterotopia have been published. The aim of this study was to describe the neuropathological features of various types of nodular heterotopia obtained from patients undergoing surgery for intractable epilepsy. METHODS: Specimens of heterotopic nodules taken from 24 patients were neuropathologically investigated using routine and immunocytochemical procedures, and the data were compared with magnetic resonance imaging (MRI), electroclinical findings, and surgical outcomes. RESULTS: The neuropathological data distinguished two groups. Group 1 (14 patients, 78% in Engel class 1) had similar characteristics regardless of the size, number, or location of the nodules, with both projecting and local circuit neurons in the nodules intermingled with glial cells. Thirteen patients had focal cortical dysplasia. The nodules were identified by MRI in all cases. In group 2 (10 patients, 90% in Engel class 1), all of the nodules were within the temporal lobe and associated with hippocampal sclerosis or gangliogliomas. They were very small (undetected by MRI) and mainly formed by projecting neurons with no evidence of glial cells. All of the patients had cortical dysplasia. DISCUSSION: The distinctive neuropathological features of the nodules in the two groups suggest different etiopathogenetic mechanisms. In group 2, the presence of nodular formations in association with cortical dysplasia and either hippocampal sclerosis or ganglioglioma raises a question concerning so-called dual pathology in the temporal lobe.