We studied 167 patients who had identifiable lesions and temporal or extratemporal partial epilepsy. Pathology included neuronal migration disorders (NMDs) (48), low-grade tumors (52), vascular malformations (34), porencephalic cysts (16), and gliotic lesions as a result of cerebral insults early in life (17). MRI volumetric studies using thin (1.5- or 3-mm) coronal images were performed in all patients and in 44 age-matched normal controls. An atrophic hippocampal formation (HF), indicating dual pathology, was present in 25 patients (15%). Abnormal HF volumes were present in those with lesions involving temporal (17%) but also extratemporal (14%) areas. Age at onset and duration of epilepsy did not influence the presence of HF atrophy. However, febrile seizures in early childhood were more frequently, although not exclusively, found in patients with hippocampal atrophy. The frequency of hippocampal atrophy in our patients with low-grade tumors (2%) and vascular lesions (9%) was low. Dual pathology was far more common in patients with NMDs (25%), porencephalic cysts (31%), and reactive gliosis (23.5%). Some structural lesions, such as NMDs, are more likely to be associated with hippocampal atrophy, independent of the distance of the lesion from the HF. In other types of lesions, such as vascular malformations, dual pathology was found when the lesion was close to the HF. A common pathogenic mechanism during pre- or perinatal development may explain the occurrence of concomitant mesial temporal sclerosis and other structural lesions because of either (1) associated developmental abnormalities or (2) predisposition to prolonged febrile convulsions.(ABSTRACT TRUNCATED AT 250 WORDS)
BackgroundBrain inflammation plays a key role in neurological disease. Although much research has been conducted investigating inflammatory events in animal models, potential differences in human brain versus rodent models makes it imperative that we also study these phenomena in human cells and tissue.MethodsPrimary human brain cell cultures were generated from biopsy tissue of patients undergoing surgery for drug-resistant epilepsy. Cells were treated with pro-inflammatory compounds IFNγ, TNFα, IL-1β, and LPS, and chemokines IP-10 and MCP-1 were measured by immunocytochemistry, western blot, and qRT-PCR. Microarray analysis was also performed on late passage cultures treated with vehicle or IFNγ and IL-1β.ResultsEarly passage human brain cell cultures were a mixture of microglia, astrocytes, fibroblasts and pericytes. Later passage cultures contained proliferating fibroblasts and pericytes only. Under basal culture conditions all cell types showed cytoplasmic NFκB indicating that they were in a non-activated state. Expression of IP-10 and MCP-1 were significantly increased in response to pro-inflammatory stimuli. The two chemokines were expressed in mixed cultures as well as cultures of fibroblasts and pericytes only. The expression of IP-10 and MCP-1 were regulated at the mRNA and protein level, and both were secreted into cell culture media. NFκB nuclear translocation was also detected in response to pro-inflammatory cues (except IFNγ) in all cell types. Microarray analysis of brain pericytes also revealed widespread changes in gene expression in response to the combination of IFNγ and IL-1β treatment including interleukins, chemokines, cellular adhesion molecules and much more.ConclusionsAdult human brain cells are sensitive to cytokine challenge. As expected ‘classical’ brain immune cells, such as microglia and astrocytes, responded to cytokine challenge but of even more interest, brain pericytes also responded to such challenge with a rich repertoire of gene expression. Immune activation of brain pericytes may play an important role in communicating inflammatory signals to and within the brain interior and may also be involved in blood brain barrier (BBB) disruption . Targeting brain pericytes, as well as microglia and astrocytes, may provide novel opportunities for reducing brain inflammation and maintaining BBB function and brain homeostasis in human brain disease.
BackgroundTransforming growth factor beta 1 (TGFβ1) is strongly induced following brain injury and polarises microglia to an anti-inflammatory phenotype. Augmentation of TGFβ1 responses may therefore be beneficial in preventing inflammation in neurological disorders including stroke and neurodegenerative diseases. However, several other cell types display immunogenic potential and identifying the effect of TGFβ1 on these cells is required to more fully understand its effects on brain inflammation. Pericytes are multifunctional cells which ensheath the brain vasculature and have garnered recent attention with respect to their immunomodulatory potential. Here, we sought to investigate the inflammatory phenotype adopted by TGFβ1-stimulated human brain pericytes.MethodsMicroarray analysis was performed to examine transcriptome-wide changes in TGFβ1-stimulated pericytes, and results were validated by qRT-PCR and cytometric bead arrays. Flow cytometry, immunocytochemistry and LDH/Alamar Blue® viability assays were utilised to examine phagocytic capacity of human brain pericytes, transcription factor modulation and pericyte health.ResultsTGFβ1 treatment of primary human brain pericytes induced the expression of several inflammatory-related genes (NOX4, COX2, IL6 and MMP2) and attenuated others (IL8, CX3CL1, MCP1 and VCAM1). A synergistic induction of IL-6 was seen with IL-1β/TGFβ1 treatment whilst TGFβ1 attenuated the IL-1β-induced expression of CX3CL1, MCP-1 and sVCAM-1. TGFβ1 was found to signal through SMAD2/3 transcription factors but did not modify nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) translocation. Furthermore, TGFβ1 attenuated the phagocytic ability of pericytes, possibly through downregulation of the scavenger receptors CD36, CD47 and CD68. Whilst TGFβ did decrease pericyte number, this was due to a reduction in proliferation, not apoptotic death or compromised cell viability.ConclusionsTGFβ1 attenuated pericyte expression of key chemokines and adhesion molecules involved in CNS leukocyte trafficking and the modulation of microglial function, as well as reduced the phagocytic ability of pericytes. However, TGFβ1 also enhanced the expression of classical pro-inflammatory cytokines and enzymes which can disrupt BBB functioning, suggesting that pericytes adopt a phenotype which is neither solely pro- nor anti-inflammatory. Whilst the effects of pericyte modulation by TGFβ1 in vivo are difficult to infer, the reduction in pericyte proliferation together with the elevated IL-6, MMP-2 and NOX4 and reduced phagocytosis suggests a detrimental action of TGFβ1 on neurovasculature.Electronic supplementary materialThe online version of this article (doi:10.1186/s12974-016-0503-0) contains supplementary material, which is available to authorized users.
Body sway and vibration perception in the lower limbs were measured in 32 normal subjects and 25 patients with peripheral neuropathies; nerve conduction studies were also performed in the patients with neuropathies. Body sway was measured by means of force-plate posturography, and three methods were used to assess vibration perception: a neurothesiometer, a semiquantitative tuning fork, and the bone vibrator of a conventional audiometer. Body sway and vibration perception were increased in the patients with peripheral neuropathies, and there was significant correlation between these measures. These findings, together with the lack of correlation between sway and muscle strength, indicate that the main source of unsteadiness in these patients is the loss of proprioceptive information. Vibration perception and body sway did not correlate with the electrophysiological variables, indicating that these measures assess different aspects of peripheral nerve function. In all subjects there was close correlation between vibration perception as assessed by the neurothesiometer and the audiometer, indicating that the audiometer could be used to screen proprioceptive fimction in patients with balance disorders. In normal subjects age correlated with vibration perception (measured with the neurothesiometer and audiometer) and also with body sway standing on foam. This suggests that the increased body sway in elderly people may partly be due to reduced proprioception in the lower limbs. (y Neurol Neurosurg Psychiatry 1995;58:335-340)
Mesial temporal lobe epilepsy (MTLE) is a neurological disorder associated with spontaneous recurrent complex partial seizures and hippocampal sclerosis. Although increased hippocampal neurogenesis has been reported in animal models of MTLE, increased neurogenesis has not been reported in the hippocampus of adult human MTLE cases. Here we showed that cells expressing doublecortin (Dcx), a microtubule-associated protein expressed in migrating neuroblasts, were present in the hippocampus and temporal cortex of the normal and MTLE adult human brain. In particular, increased numbers of Dcx-positive cells were observed in the epileptic compared with the normal temporal cortex. Importantly, 56% of Dcx-expressing cells in the epileptic temporal cortex coexpressed both the proliferative cell marker, proliferating cell nuclear antigen and early neuronal marker, TuJ1, suggesting that they may be newly generated neurons. A subpopulation of Dcx-positive cells in the epileptic temporal cortex also coexpressed the mature neuronal marker, NeuN, suggesting that epilepsy may promote the generation of new neurons in the temporal cortex. This study has identified, for the first time, a novel population of Dcx-positive cells in the adult human temporal cortex that can be upregulated by epilepsy and thus, raises the possibility that these cells may have functional significance in the pathophysiology of epilepsy.
Microglia, the resident macrophages of the central nervous system play vital roles in brain homeostasis through clearance of pathogenic material. Microglia are also implicated in neurological disorders through uncontrolled activation and inflammatory responses. To date, the vast majority of microglial studies have been performed using rodent models. Human microglia differ from rodent counterparts in several aspects including their response to pharmacological substances and their inflammatory secretions. Such differences highlight the need for studies on primary adult human brain microglia and methods to isolate them are therefore required. Our procedure generates microglial cultures of >95% purity from both biopsy and autopsy human brain tissue using a very simple media-based culture procedure that takes advantage of the adherent properties of these cells. Microglia obtained in this manner can be utilised for research within a week. Isolated microglia demonstrate phagocytic ability and respond to inflammatory stimuli and their purity makes them suitable for numerous other forms of in vitro studies, including secretome and transcriptome analysis. Furthermore, this protocol allows for the simultaneous isolation of neural precursor cells during the microglial isolation procedure. As human brain tissue is such a precious and valuable resource the simultaneous isolation of multiple cell types is highly beneficial.
Cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) is a recently recognized neurodegenerative ganglionopathy. Prompted by the presence of symptomatic postural hypotension in two patients with CANVAS, we hypothesized that autonomic dysfunction may be an associated feature of the syndrome. We assessed symptoms of autonomic dysfunction and performed autonomic nervous system testing among 26 patients from New Zealand. After excluding three patients with diabetes mellitus, 83% had evidence of autonomic dysfunction; all patients had at least one autonomic symptom and 91% had more than two symptoms. We also found a higher rate of downbeat nystagmus (65%) than previously described in CANVAS. We confirmed that sensory findings on nerve conduction tests were consistent with a sensory ganglionopathy and describe two patients with loss of trigeminal sensation consistent with previous pathological descriptions of trigeminal sensory ganglionopathy. Our results suggest that autonomic dysfunction is a major feature of CANVAS. This has implications for the management of patients with CANVAS as the autonomic symptoms may be amenable to treatment. The findings also provide an important differential diagnosis from multiple system atrophy for patients who present with ataxia and autonomic failure.
Objective This study was undertaken to develop consensus‐based recommendations for the management of adult and pediatric patients with new onset refractory status epilepticus (NORSE)/febrile infection‐related epilepsy syndrome (FIRES) based on best evidence and experience. Methods The Delphi methodology was followed. A facilitator group of nine experts was established, who defined the scope, users, and suggestions for recommendations. Following a review of the current literature, recommendation statements concerning diagnosis, treatment, and research directions were generated, which were then rated on a scale of 1 (strongly disagree) to 9 (strongly agree) by a panel of 48 experts in the field. Consensus that a statement was appropriate was reached if the median score was ≥7 and inappropriate if the median score was ≤3. The analysis of evidence was mapped to the results of each statement included in the Delphi survey. Results Overall, 85 recommendation statements achieved consensus. The recommendations are divided into five sections: (1) disease characteristics; (2) diagnostic testing and sampling; (3) acute treatment; (4) treatment in the postacute phase; and (5) research, registries, and future directions in NORSE/FIRES. The detailed results and discussion of all 85 statements are outlined herein. A corresponding summary of findings and practical flowsheets are presented in a companion article. Significance This detailed analysis offers insight into the supporting evidence and the current gaps in the literature that are associated with expert consensus statements related to NORSE/FIRES. The recommendations generated by this consensus can be used as a guide for the diagnosis, evaluation, and management of patients with NORSE/FIRES, and for planning of future research.
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