Disrupting epileptiform activity by preventing parvalbumin interneuron depolarization block

Background. In the international clinical practice there have been occasional reports of phenylketonuria (PKU) and cystic fibrosis (CF) found simultaneously in the same patient. Both PKU and CF are the inherited disorders characterized by autosomal recessive type of inheritance. Currently the combination of two or more inherited disorders in one patient is considered to be a clinical rarity.Case description. This is a clinical case of two genetic disorders, CF and PKU, combined in a 5-year old patient who had been followed up since birth. Owing to implementation of neonatal screening for inherited and congenital diseases into clinical practice, during the first month of life the infant was diagnosed with CF (diagnostically significant elevation of immunoreactive trypsin [IRT] at the initial [163.2 ng/mL] and repeat testing on day 21 of life [138.7 ng/mL]) and PKU (phenylalanine [PA] level 15.9 mg/dL). Both disorders have been confirmed by genetic tests, i.e., homozygous DelF508 mutation was found in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, and P281L mutation in the phenylalanine hydroxylase (PAH) gene was also present in homozygous state. Child’s parents strictly adhered to dietary and treatment recommendations. By the age of 5 years the child developed symptoms of neurological disorder and disorder of the respiratory system, cognitive impairment and delay in speech development, subclinical epileptiform activity with high risk of epilepsy, and chronic inflammation of the respiratory tract.Conclusion. This case report demonstrates the important role of neonatal screening in early diagnosis and timely start of therapy, and underscores the importance of continuous medication in such genetic disorders as CF and PKU. On the whole, such approach brings about a relative preservation of functioning of the most affected organs and systems. By the age of 5 years the child does not form bronchiectases, shows no signs of chronic hypoxia, nutritional deficiency or pronounced neurologic deficit, and is at low risk for the development of autism spectrum disorder. At the same time, the larger scale and longer-term observations are required in order to make the unequivocal conclusions about the prognosis of these diseases under conditions of modern-day medical follow-up.

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Succinic Semialdehyde Dehydrogenase Deficiency: Review of the Natural History Study

Journal of Child Neurology ◽

10.1177/0883073820981262 ◽

2021 ◽

pp. 088307382098126

Author(s):

Phillip L. Pearl ◽

Melissa L. DiBacco ◽

Christos Papadelis ◽

Thomas Opladen ◽

Ellen Hanson ◽

...

Keyword(s):

Natural History ◽

Psychiatric Symptoms ◽

Epileptiform Activity ◽

Laboratory Data ◽

Standard Of Care ◽

Succinic Semialdehyde ◽

Succinic Semialdehyde Dehydrogenase ◽

Natural History Study ◽

Semialdehyde Dehydrogenase ◽

Verbal Score

Objective: The SSADHD Natural History Study was initiated in 2019 to define the natural course and identify biomarkers correlating with severity. Methods: The study is conducted by 4 institutions: BCH (US clinical), WSU (bioanalytical core), USF (biostatistical core), and Heidelberg (iNTD), with support from the family advocacy group (SSADH Association). Recruitment goals were to study 20 patients on-site at BCH, 10 with iNTD, and 25 as a standard-of care cohort. Results: At this half-way point of this longitudinal study, 28 subjects have been recruited (57% female, mean 9 years, range 18 months–40 years). Epilepsy is present in half and increases in incidence and severity, as do psychiatric symptoms, in adolescence and adulthood. The average Full Scale IQ (FSIQ) was 53 (Verbal score of 56, Non Verbal score of 49), and half scored as having ASD. Although there was no correlation between gene variant and phenotypic severity, there were extreme cases of lowest functioning in one individual and highest in another that may have genotype-phenotype correlation. The most common EEG finding was mild background slowing with rare epileptiform activity, whereas high-density EEG and magnetoencephalography showed reduction in the gamma frequency band consistent with GABAergic dysfunction. MR spectroscopy showed elevations in the GABA/NAA ratio in all regions studied with no crossover between subjects and controls. Conclusions: The SSADH Natural History Study is providing a unique opportunity to study the complex pathophysiology longitudinally and derive electrophysiologic, neuroimaging, and laboratory data for correlation and to serve as biomarkers for clinical trials and prognostic assessments in this ultra-rare inherited disorder of GABA metabolism.

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Induction of Tertiary Phase Epileptiform Discharges after Postasphyxial Infusion of a Toll-Like Receptor 7 Agonist in Preterm Fetal Sheep

International Journal of Molecular Sciences ◽

10.3390/ijms22126593 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6593

Author(s):

Kenta H.T. Cho ◽

Mhoyra Fraser ◽

Bing Xu ◽

Justin M. Dean ◽

Alistair J. Gunn ◽

...

Keyword(s):

Moderate Hypertension ◽

Epileptiform Activity ◽

Ischemic Brain Injury ◽

Toll Like Receptor ◽

Fetal Sheep ◽

Ischemic Brain ◽

Tlr Agonists ◽

Epileptiform Discharges ◽

Subcortical Regions ◽

Total Burden

Background: Toll-like receptor (TLR) agonists are key immunomodulatory factors that can markedly ameliorate or exacerbate hypoxic–ischemic brain injury. We recently demonstrated that central infusion of the TLR7 agonist Gardiquimod (GDQ) following asphyxia was highly neuroprotective after 3 days but not 7 days of recovery. We hypothesize that this apparent transient neuroprotection is associated with modulation of seizure-genic processes and hemodynamic control. Methods: Fetuses received sham asphyxia or asphyxia induced by umbilical cord occlusion (20.9 ± 0.5 min) and were monitored continuously for 7 days. GDQ 3.34 mg or vehicle were infused intracerebroventricularly from 1 to 4 h after asphyxia. Results: GDQ infusion was associated with sustained moderate hypertension that resolved after 72 h recovery. Electrophysiologically, GDQ infusion was associated with reduced number and burden of postasphyxial seizures in the first 18 h of recovery (p < 0.05). Subsequently, GDQ was associated with induction of slow rhythmic epileptiform discharges (EDs) from 72 to 96 h of recovery (p < 0.05 vs asphyxia + vehicle). The total burden of EDs was associated with reduced numbers of neurons in the caudate nucleus (r2 = 0.61, p < 0.05) and CA1/2 hippocampal region (r2 = 0.66, p < 0.05). Conclusion: These data demonstrate that TLR7 activation by GDQ modulated blood pressure and suppressed seizures in the early phase of postasphyxial recovery, with subsequent prolonged induction of epileptiform activity. Speculatively, this may reflect delayed loss of early protection or contribute to differential neuronal survival in subcortical regions.

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Transcriptional and morphological profiling of parvalbumin interneuron subpopulations in the mouse hippocampus

Nature Communications ◽

10.1038/s41467-020-20328-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Lin Que ◽

David Lukacsovich ◽

Wenshu Luo ◽

Csaba Földy

Keyword(s):

Large Scale ◽

Cell Types ◽

Rna Seq ◽

Neuronal Identity ◽

Parvalbumin Interneurons ◽

Different Types ◽

Parvalbumin Interneuron ◽

Cam Profile ◽

Developmental Domains

AbstractThe diversity reflected by >100 different neural cell types fundamentally contributes to brain function and a central idea is that neuronal identity can be inferred from genetic information. Recent large-scale transcriptomic assays seem to confirm this hypothesis, but a lack of morphological information has limited the identification of several known cell types. In this study, we used single-cell RNA-seq in morphologically identified parvalbumin interneurons (PV-INs), and studied their transcriptomic states in the morphological, physiological, and developmental domains. Overall, we find high transcriptomic similarity among PV-INs, with few genes showing divergent expression between morphologically different types. Furthermore, PV-INs show a uniform synaptic cell adhesion molecule (CAM) profile, suggesting that CAM expression in mature PV cells does not reflect wiring specificity after development. Together, our results suggest that while PV-INs differ in anatomy and in vivo activity, their continuous transcriptomic and homogenous biophysical landscapes are not predictive of these distinct identities.

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Depth Electrode Guided Anterior Insulectomy: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opab112 ◽

2021 ◽

Author(s):

Mauricio Mandel ◽

Layton Lamsam ◽

Pue Farooque ◽

Dennis Spencer ◽

Eyiyemisi Damisah

Keyword(s):

Right Hemisphere ◽

Preoperative Evaluation ◽

Epileptiform Activity ◽

Neurological Deficits ◽

Depth Electrodes ◽

Depth Electrode ◽

Patient Reported ◽

Frontal Operculum ◽

History Of ◽

Electroencephalogram Eeg

Abstract The insula is well established as an epileptogenic area.1 Insular epilepsy surgery demands precise anatomic knowledge2-4 and tailored removal of the epileptic zone with careful neuromonitoring.5 We present an operative video illustrating an intracranial electroencephalogram (EEG) depth electrode guided anterior insulectomy. We report a 17-yr-old right-handed woman with a 4-yr history of medically refractory epilepsy. The patient reported daily nocturnal ictal vocalization preceded by an indescribable feeling. Preoperative evaluation was suggestive of a right frontal-temporal onset, but the noninvasive results were discordant. She underwent a combined intracranial EEG study with a frontal-parietal grid, with strips and depth electrodes covering the entire right hemisphere. Epileptiform activity was observed in contact 6 of the anterior insula electrode. The patient consented to the procedure and to the publication of her images. A right anterior insulectomy was performed. First, a portion of the frontal operculum was resected and neuronavigation was used for the initial insula localization. However, due to unreliable neuronavigation (ie, brain shift), the medial and anterior borders of the insular resection were guided by the depth electrode reference. The patient was discharged 3 d after surgery with no neurological deficits and remains seizure free. We demonstrate that depth electrode guided insular surgery is a safe and precise technique, leading to an optimal outcome.

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Electroencephalography in systemic lupus erythematosus patients with neuropsychiatric manifestations

The Egyptian Journal of Internal Medicine ◽

10.1186/s43162-020-00012-1 ◽

2020 ◽

Vol 32 (1) ◽

Author(s):

Howaida E. Mansour ◽

Reem A. Habeeb ◽

Noran O. El-Azizi ◽

Heba H. Afeefy ◽

Marwa A. Nassef ◽

...

Keyword(s):

Systemic Lupus Erythematosus ◽

Lupus Erythematosus ◽

Epileptiform Activity ◽

Brain Mri ◽

Periventricular White Matter ◽

Normal Brain ◽

Systemic Lupus ◽

Specific Test ◽

Eeg Abnormalities ◽

Neuropsychiatric Manifestations

Abstract Background Neuropsychiatric manifestations are frequently reported in systemic lupus erythematosus (SLE) patients. This study was done to describe electroencephalographic (EEG) findings in SLE patients with neuropsychiatric manifestation (NPSLE). Results Among 60 SLE patients, there were 50 females (83.3%) and 10 males (16.7%). EEG abnormalities were reported in 12 patients out of 30 (40%) with NPSLE, while all patients with non-NPSLE (n = 30) had no EEG abnormalities; diffuse slowing (20%) was the most common abnormalities, followed by generalized epileptiform activity (13.3%), and lastly temporal epileptiform activity (6.7%). Seizure was the most reported neuropsychiatric disorder in 13 patients (43.3%); 8 of them had abnormal EEG (61.5%). Periventricular white matter lesion (23.3%) followed by infarction (13.3%) were the most common MRI brain findings among 53.3% of NPSLE group. Half of the cases with EEG abnormality had normal brain MRI. SLEDAI score and ACL IgM positivity were higher in the NPSLE group than the non-NPSLE group. EEG is not a sensitive or specific test for detecting NPSLE with sensitivity (37.5%) and specificity (57.1%). Conclusion Not all patients with NPSLE must have abnormal brain MRI or EEG. EEG is a useful assistant tool in the assessment of different manifestations of NPSLE, but it cannot be used as a screening test alone and must be supplemented by neuroimaging studies.

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