ARTICLE | doi:10.20944/preprints201612.0151.v1
Online: 30 December 2016 (07:43:42 CET)
Mesial temporal lobe epilepsy (mTLE) is one of the most common and refractory focal epilepsy syndromes. The molecular mechanisms of TLE are not completely understood. The aim of this study was to investigate the expression and potential function of plasma exosomal miRNAs (miR-483-5p, miR-671-5p, and miR-150-3p) in a mouse mode and in temporal lobe epilepsy patients. It was found that exosomal miRNAs were differentially expressed in three phases of the mouse mode, and exosomal miRNAs were down-regulated in mTLE patients compared with healthy controls. A bioinformatics analysis showed that target genes of exosomal miRNAs were significantly involved in the apoptotic process, cell adhesion, nervous system development, neurotrophin signaling pathway, PI3K-Akt signaling pathway, and metabolic pathways. The areas under the curve of miR-483-5p and miR-150-3p were 0.8714 (sensitivity = 75.00%, specificity = 91.65%) and 0.8213 (sensitivity = 67.50%, specificity = 90.00%), respectively. More importantly, the exosomal miRNAs were significantly associated with clinical parameters. Exosomal miRNAs may have the potential to become diagnostic and therapeutic biomarkers.
SHORT NOTE | doi:10.20944/preprints202312.0622.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Epilepsy; Awareness; Prevention; SUDEP
Online: 8 December 2023 (17:03:46 CET)
SUDEP is a sudden death in a person with epilepsy, without evidence of a seizure before death. While its cause is still unclear, various factors have been linked to seizure onset and cardiopulmonary function. Studies have shown that although 91.3% of epilepsy patients want information on premature death, only 31% of them receive it. The numbers emphasize the need for open and sensitive communication by medical professionals. It is important to choose the appropriate moment for the conversation, avoiding periods of stress and ensuring emotional stability in the patient, as well as clear, appropriate and easy to comprehend information about SUDEP. To facilitate this, knowing the patient's level of knowledge is essential. Education on the warning signs of seizures and SUDEP can help take precautions and can decrease the incidence of the phenomenon itself. Effective epilepsy care requires a comprehensive plan, including medication adherence and lifestyle changes. Regular communication and collaboration between the patient, caregiver and health professionals are essential for the effective management of epilepsy, so just as epilepsy has a fluid, changeable course of disease and follow-up appointments are very important, the topic of SUDEP is not a one-time conversation either.
ARTICLE | doi:10.20944/preprints202109.0316.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: temporal lobe epilepsy; hippocampus; 4-aminopyridine; epilepsy model; long-term potentiation; AMPA receptor.
Online: 17 September 2021 (12:45:31 CEST)
Even brief epileptic seizures can lead to activity-dependent structural remodeling of neural circuitry. Animal models show that the functional plasticity of synapses and changes in the intrinsic excitability of neurons can be crucial for epileptogenesis. However, the exact mechanisms underlying epileptogenesis remain unclear. We induced epileptiform activity in rat hippocampal slices for 15 min using a 4-aminopyridine (4-AP) in vitro model and observed hippocampal hyperexcitability for at least 1 hour. We tested several possible mechanisms of this hyperexcitability, including changes in intrinsic membrane properties of neurons, presynaptic and postsynaptic alterations. Neither input resistance nor other essential biophysical properties of hippocampal CA1 pyramidal neurons were affected by epileptiform activity. The glutamate release probability also remained unchanged, as the frequency of miniature EPSCs and the paired amplitude ratio of evoked responses did not change after epileptiform activity. However, we found an increase in the AMPA/NMDA ratio, suggesting alterations in the properties of postsynaptic glutamatergic receptors. Thus, the increase in excitability of hippocampal neural networks is realized through postsynaptic mechanisms. In contrast, the intrinsic membrane properties of neurons and the probability of glutamate release from presynaptic terminals are not affected in a 4-AP model.
ARTICLE | doi:10.20944/preprints202309.1353.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: dopamine; D1-like dopamine receptors; D2-like dopamine receptors; prefrontal cortex; generalized epilepsy; absence epilepsy; audiogenic epilepsy; animal model; autism spectrum disorder; phenotype
Online: 20 September 2023 (08:51:40 CEST)
The involvement of the prefrontal cortical dopaminergic system in psychopathology of epilepsies and comorbid conditions such as autism spectrum disorder (ASD) still needs to be explored. We used autoradiography to study the D1-like (D1DR) and D2-like (D2DR) receptor binding density in the prefrontal cortex of normal Wistar rats and Wistar-derived strains with generalized convulsive and/or nonconvulsive epilepsies. WAG/Rij rats served as a model for non-convulsive absence epilepsy, WAG/Rij-AGS as a model of mixed convulsive/non-convulsive forms, and KM strain was a model for convulsive epilepsy comorbiding with ASD-like behavioral phenotype. Prefrontal cortex of rats with any of epileptic pathology studied, demonstrated profound decreases in binding densities to both D1DR, D2DR; the effects were localized in the primary and secondary anterior cingulate cortexi, and adjacent regions. The local decreased D1DR and D2DR binding densities were independent (not correlated) from each other. The particular group of epileptic rats with ASD-like phenotype (KM strain), displayed changes in the lateral prefrontal cortex and adjacent regions: D1DR were lowered, but those to D2DR elevated, in anterior dysgranular insular cortex and adjacent regions. Thus, epilepsy-related changes in the dopaminergic system of rat archeocortex were localized in the medial regions, whereas ASD-related candidates were seen in the lateral aspects. The findings point to putative local dopaminergic dysfunctions, associated with generalized epilepsies and/or ASD.
REVIEW | doi:10.20944/preprints202301.0531.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: astrocyte; gap junction coupling; connexin 43; connexin 30; hippocampus, epilepsy; ep-ileptogenesis; temporal lobe epilepsy
Online: 30 January 2023 (02:07:39 CET)
The gap junction-coupled astroglial network plays a central role in the regulation of neuronal activity and synchronization, but its involvement in the pathogenesis of neuronal diseases is not yet understood. Here we present the current state of knowledge about the impact of impaired glial coupling in the development and progression of epilepsy and discuss whether astrocytes represent alternative therapeutic targets. We focus mainly on temporal lobe epilepsy (TLE), which is the most common form of epilepsy in adults, characterized by high therapy resistance. Functional data from TLE patients and corresponding experimental models point to a complete loss of astrocytic coupling, but preservation of the gap junction forming proteins connexin43 (Cx43) and connexin30 (Cx30) in hippocampal sclerosis. Several studies further indicate that astrocyte uncoupling represents a causal event in the initiation of TLE, as it occurs very early in epileptogenesis, clearly preceding dysfunctional changes in neurons. However, more research is needed to fully understand the role of gap junction channels in epilepsy and to develop safe and effective therapeutic strategies targeting astrocytes.
ARTICLE | doi:10.20944/preprints202309.0663.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Drug-resistant epilepsy; Hemispherotomy; Surgical procedure.
Online: 11 September 2023 (10:15:13 CEST)
(1) Background: Hemispherotomy is the generally accepted treatment for hemispheric drug resistant epilepsy (DRE). Lateral or vertical approaches are performed according to the surgeon's preference. Multiples technical variations have been proposed since Delalande first described his vertical technique. We propose a sub-insular variation of the vertical parasagittal hemispherotomy (VPH) and describe our case series of patients operated on with this procedure. (2) Methods: a continuous series of patients operated on by the senior author (CR) with the modified sub-insular VPH was retrospectively analyzed. We report the demographic pre-operative characteristics, epilepsy and functional outcome as well as the surgical complications.(3) Results: Twenty-five patients were operated on between August 2008 and August 2023, twenty-three of them have at least a 3-month follow-up. On this last group 86,3% of patients were seizure-free. Only two patients developed post-operative hydrocephalus (8.7%), all patients with autonomous preoperative walk and 86,3% of the total series were able to walk without assistance (86.3%) and perform adapted social activities at last follow-up.(4) Conclusion: The modified vertical parasagittal sub-insular hemispherotomy is a successful surgical technique for hemispheric DRE with seizure freedom rates similar to the biggest series reported in the literature. Compared to other series, patients operated with our modified technique had a lower rate of postoperative hydrocephalus and excellent long-term motor and cognitive outcome.
ARTICLE | doi:10.20944/preprints202308.1532.v1
Subject: Public Health And Healthcare, Public Health And Health Services Keywords: generic medicines; opinion; patients; epilepsy; Poland
Online: 22 August 2023 (09:37:57 CEST)
Aim: The majority of medicines used in Poland are generic drugs – substitutions of the original. Objective of the study was to obtain information on the current knowledge about generic medicines among Polish patients with epilepsy. Material and Methods: The study was conducted based on a self-developed questionnaire. The questionnaire consisted of 25 questions, including questions regarding their knowledge about generics, their previous experience and the factors behind these choices. Results: Overall, 1220 questionnaires were analyzed. Among all patients, 66.39% reportedly heard about generics. Of these 61.48% of patients had used the generic drugs in past. A significant proportion of participants had never been recommended to switch to a generic medicine by their health care professional (22.95% physician and 13.93% pharmacist). Statistically relevant differences were observed regarding the respondents’ kind and level of education, place of residence, and net income per household. Conclusions: Significant gaps were identified in the knowledge and perceptions among patients regarding generic medicines especially in relation to efficacy and safety of generic medicines. Efforts must be directed towards increasing public awareness of generic medicines and should also focus on educating patients about generic medicines.
ARTICLE | doi:10.20944/preprints202305.1927.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: COVID19; Children; Epilepsy; Adolescents; Pediatric; Pandemic
Online: 26 May 2023 (11:00:40 CEST)
The coronavirus disease 2019 (COVID-19) pandemic has disrupted health care worldwide. As the pandemic has been prolonged, quarantine restrictions have been lightened gradu-ally, which can influence outcomes of pediatric patients with chronic disease such as epi-lepsy by increase of susceptibility of the COVID-19 infection. The aim of this study was to determine impacts of COVID-19 pandemic on seizure control and identify potential risk factors that might worsen seizure attacks during the pandemic in children with epilepsy. We performed a retrospective chart review of 48 pediatric patients with epilepsy during the COVID-19 pandemic from January 2016 to July 2022. During the COVID-19 pandemic period, 25% of pediatric patients experienced sei-zure worsening, showing an increase in seizure frequency or duration or both. Factors associated with worsening seizures during pandemic were: diagnosis of epi-lepsy less than one year, comorbid conditions with cerebral palsy or having a tracheosto-my or a PEG, and infection with other viruses (respiratory syncytial virus, influenza virus A, influenza virus B) rather than COVID-19 infection. Our finding highlights the need to proactively monitor and regularly follow up (es-pecially short period of time) patients after they are diagnosed with epilepsy. It is also important to properly manage those who are susceptible to serious illness and keep sea-sonal viral infections under surveillance to manage exacerbated seizure in children with epilepsy. Furthermore, pediatric physicians should not overlook surveillance of seasonal respiratory viruses since quarantine restrictions are getting eased.
REVIEW | doi:10.20944/preprints202202.0259.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Epilepsy; Neuroimmunology; Neuroinflammation; Epileptogenesis; Personalized medicine
Online: 21 February 2022 (14:59:18 CET)
Background: Immunologic and neuro-inflammatory pathways have been found to play a major role in the pathogenesis of many neurological disorders such as epilepsy, proposing the use of novel therapeutic strategies. In the era of personalized medicine and in the face of the exhaustion of anti-seizure therapeutic resources it is worth looking at the current or future possibilities that neuroimmunomodulator or anti-inflammatory therapy can offer us in the management of patients with epilepsy. Methods: We performed a narrative review on the recent advances on the basic epileptogenic mechanisms related to the activation of immunity or neuroinflammation with special attention to current and future opportunities for novel treatments in epilepsy. Results: Neuroinflammation can be considered a universal phenomenon and occurs in structural, infectious, post-traumatic, autoimmune, or even genetically based epilepsies. The emerging research developed in recent years has allowed us to identify the main molecular pathways in-volved in these processes. These molecular pathways could constitute future therapeutic targets for epilepsy. Conclusions: Different drugs current or in development have demonstrated their capacity to inhibit or modulate molecular pathways involved in the immunologic or neuroinflammatory mechanisms described in epilepsy. Some of them should be tested in the future as possible antiepileptic drugs.
Subject: Biology And Life Sciences, Behavioral Sciences Keywords: Elderly; epilepsy; stroke; Parkinson’s disease; fall
Online: 7 February 2019 (11:26:29 CET)
Introduction: Epilepsy is one of the most common neurological diseases. Epilepsy poses a significant burden on the quality of life of affected individuals and their families. The aim of this study was to determine the psychiatric disorders in epileptic patients. Methods and Materials: This descriptive-analytical study was conducted in 2017 with a simple random sampling method on patients with epilepsy who admitted to the neurology department. Results: Among the 150 examined patients, 88 (58.7%) were female and 63(42%) had epilepsy more than 10 years. The most common psychiatric disorder among epileptic patients was depression (68 patients = 45.3%) and anxiety (65 patients = 43.3%) patients. Conclusion: Most of patients had more than 10 years history of epilepsy. Also, Anxiety and depression were the most common symptoms in epileptic patients. It need to more study to determine the psychiatric disorders in epileptic patients.
REVIEW | doi:10.20944/preprints202309.0536.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: PET; MRI; SPECT; CT; Depression; Epilepsy; Atrophy
Online: 7 September 2023 (11:26:01 CEST)
Imaging-based biomarkers have developed as an effective tool in neurology, providing vital understandings of the structural, functional, and molecular changes associated with neurological disorders. Imaging techniques such as magnetic resonance imaging (MRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and computed tomography (CT) have been widely employed to record disease-related alterations in the brain. These techniques provide a wide range of biomarkers, such as functional connectivity patterns, volumetric measurements, molecular imaging agents, and perfusion parameters, enabling the correct identification of neurological disorders. These biomarkers have proven useful in early diagnosis, disease progression tracking, therapy response prediction, and surgical planning. This review emphasizes the various obstacles and limitations that are associated with imaging-based biomarkers. Technical constraints, standardization obstacles, ethical concerns, regulatory challenges, and cost-effectiveness concerns all offer substantial barriers to wider use. It is vital to overcome these challenges if imaging biomarkers are to be successfully integrated into routine clinical practice. Imaging technology advancements like high-resolution imaging, multimodal imaging, and artificial intelligence-based analysis hold immense promise for imaging-based biomarkers in the future. While more study and standardization are needed, their ongoing development and integration into clinical practice have the potential to revolutionize the diagnosis, treatment, and management of neurological disorders, resulting in better patient care and outcomes.
ARTICLE | doi:10.20944/preprints202212.0515.v1
Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: Mansonella perstans; onchocerciasis; nodding syndrome; epilepsy; Tanzania
Online: 27 December 2022 (09:20:31 CET)
In South Sudan, three case-control studies found a positive association between Nodding Syn-drome (NS) and a Mansonella perstans infection. To investigate whether M. perstans could play the primary and sole causal role in the development of NS, we examined blood films of persons with and without epilepsy in rural villages affected by NS in Mahenge, Tanzania, to identify M. perstans infections. Study participants were also examined for onchocercal nodules and skin lesions and tested for the presence of anti-O. volvulus antibodies (Ov16 ELISA). One hundred and thirteen epilepsy cases and 132 controls were enrolled, with a mean age of 28.3 years (interquartile range 22 – 34 years); 125 (51%) were females. Of the persons with epilepsy, 43 (38.1%) met the probable NS criteria. M. perstans infection was absent in all participants, but Ov16 prevalence and oncho-cerciasis-associated skin manifestations were positively associated with epilepsy, including probable NS. Onchocercal nodules in the mothers of cases were also positively associated with epilepsy. In conclusion, in contrast with O. volvulus, M. perstans is likely not endemic in Mahenge and therefore cannot be a co-factor for NS in the area. Hence, this filaria cannot be the primary and sole causal factor in the development of NS.
ARTICLE | doi:10.20944/preprints202210.0300.v1
Subject: Biology And Life Sciences, Cell And Developmental Biology Keywords: Nrf2; Oxidative stress; Antioxidants; Pentylenetetrazol; Epilepsy; Seizure
Online: 20 October 2022 (08:29:58 CEST)
The modulation of Nrf2 activity has been reported to be implicated in the pathology of various neurological disorders, including epilepsy. Previous studies have demonstrated that Nrf2 is activated in the post-status epilepticus rat model, however, the spatio-temporal, as well as cell type-specific expression of Nrf2 following brief epileptic seizures remains unclear. Here, we evaluated how an acute epileptic seizure affected the expression of Nrf2 and its downstream genes in the cortex and the hippocampus up to 1-week following the induced seizure. We found that after a pentylenetetrazol-induced seizure, Nrf2 significantly increased at 24 h at the mRNA level and 3 to 6 h at the protein level in the cortex. In the hippocampus, the Nrf2 mRNA level peaked at 3 h after the seizure, and no significant changes were observed in the protein level. Interestingly, the mRNA level of Nrf2 downstream genes peaked at 3-6 h after seizure in both the cortex and the hippocampus. A significant increase in the expression of Nrf2 was observed in the neuronal population of CA1 and CA3 regions of the hippocampus, as well as in the cortex. Moreover, we observed no change in the co-localization of Nrf2 with astrocytes neither in the cortex nor in CA1 and CA3. Our results revealed that following a brief acute epileptic seizure, the expression of Nrf2 and its downstream genes is transiently increased and peaked at early timepoints after seizure predominantly in the hippocampus, and this expression is restricted to the neuronal population.
ARTICLE | doi:10.20944/preprints202203.0180.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: seizures; epilepsy; Alzheimer’s disease; antiseizure medications; hyperexcitability
Online: 14 March 2022 (09:36:19 CET)
Epilepsy and Alzheimer's disease (AD) incidence increase with age. There are reciprocal relationships between epilepsy and AD. Epilepsy is a risk factor for AD and, in turn, AD is an independent risk factor for developing epilepsy in old age and abnormal AD biomarkers in PET and or CSF are frequently found in late onset epilepsies of unknown etiology. Accordingly, epilepsy and AD share pathophysiological processes including neuronal hyperexcitability and an early excitatory-inhibitory dysregulation leading to dysfunction in the inhibitory GABAergic and excitatory glutamatergic systems. Moreover, both β-amyloid and tau protein aggregates, the anatomopathological hallmarks of AD, have proepileptic effects. Finally, these aggregates have been found in the resection material of refractory temporal lobe epilepsies suggesting that epilepsy leads to amyloid and tau aggregates. Some epileptic syndromes, such as medial temporal lobe epilepsy share structural and functional neuroimaging findings with AD, leading to overlapping symptomatology such as episodic memory deficits and toxic synergistic effects. In this respect, the existence of epileptiform activity and electroclinical seizures in AD appears to accelerate progression of cognitive decline and the presence of cognitive decline is much more prevalent in epileptic patients than in elderly without epilepsy. Notwithstanding their clinical significance, the diagnosis of clinical seizures in AD is a challenge. Most are focal and manifest with altered level of consciousness without motor symptoms, and are often interpreted as cognitive fluctuations. Finally, despite the frequent association of epilepsy and AD dementia, there is a lack of clinical trials to guide the use of antiseizure medications (ASM). There is also a potential role for ASMs to be used as disease-modifying drugs in AD.
ARTICLE | doi:10.20944/preprints202202.0270.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Onchocerciasis; Onchocerca volvulus; epilepsy; nodding syndrome; ivermectin
Online: 22 February 2022 (11:10:26 CET)
A two phase survey of epilepsy was conducted in selected villages in Mundri West and East Counties (26 June−8 July, 2021), an onchocerciasis-endemic area in Western Equatoria State in South Sudan. In the first phase, households were visited by a trained research team to identify persons suspected to have epilepsy. In the second phase, persons suspected to have epilepsy were interviewed and examined by a clinician to confirm the diagnosis. A total of 364 households agreed to participate in the survey, amounting to 2,588 individuals. The epilepsy screening questionnaire identified 91 (3.5%) persons suspected to have epilepsy, of whom in 86 (94.5%) the diagnosis of epilepsy was confirmed by a clinician. The overall prevalence of confirmed epilepsy was 3.3% (95% CI: 2.7-4.1%), and of nodding syndrome 0.9% (95% CI: 0.6-1.4%). In 61 (16.8%) households there was at least one person with epilepsy. Only 1,212 (46.9%) of 2,583 people took ivermectin during the last distribution round in 2021. The annual epilepsy incidence was 77.3/100.000 (95% CI: 9.4-278.9/100,000) and the annual epilepsy mortality 251.2/100,000 (95% CI: 133.8-428.7/100,000). In conclusion, a high prevalence and incidence of epilepsy was observed in villages in Mundri. Urgent action is needed to prevent children from developing onchocerciasis-associated epilepsy by strengthening the local onchocerciasis elimination programme.
ARTICLE | doi:10.20944/preprints202110.0415.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: epilepsy; hydrogen sulfide; corneal kindled mice, mitochondrial dysfunction, oxidative stress, LC-MS/MS; temporal lobe epilepsy; neurological disorder; gasotransmitter
Online: 27 October 2021 (13:36:04 CEST)
Epilepsy is a heterogenous neurological disorder characterized by recurrent unprovoked seizures, mitochondrial stress, and neurodegeneration. Hydrogen sulfide (H2S), a gasotransmitter, promotes mitochondrial function and biogenesis, elicits neuromodulation and neuroprotection, and may acutely suppress seizures. A major gap in knowledge remains in understanding the role of mitochondrial dysfunction and progressive changes in H2S levels following acute seizures and during epileptogenesis. We thus sought to quantify changes in H2S and its methylated metabolite (MeSH) via LC-MS/MS subsequent to acute maximal electroshock and 6 Hz 44 mA seizures in mice, as well as in the corneal kindled mouse model of chronic seizures. Plasma H2S was acutely reduced after a maximal electroshock seizure. H2S or MeSH levels in whole brain homogenate and expression of related genes in corneal kindled mice were not altered. However, plasma H2S and MeSH levels were significantly lower during kindling, but not after established kindling. Morever, we demonstrated a time-dependent increase in expression of mitochondrial membrane integrity-related proteins, Opa1, Mfn2, Drp1, and Mff during kindling, which did not correlate with gene expression. Taken together, short-term reductions in plasma H2S could be a novel biomarker for seizures. Future studies should further define the role of H2S and mitochondrial stress in epilepsy.
ARTICLE | doi:10.20944/preprints202307.0895.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Event Related Potentials; Epilepsy; P300; Anti-Seizure Medication
Online: 13 July 2023 (07:40:09 CEST)
Background: Epileptic patients frequently encounter cognitive impairment. Functions that are mostly affected involve memory, attention and executive function; however this is mainly dependant on the location of the epileptic activity. The aim of the study is to assess cognitive functions in MRI-negative epilepsy patients by means of neurophysiological and neuropsychological measures. Methods: The patients were enrolled from the outpatient Epilepsy/Clinical Neurophysiology clinic over a time period of 6 months. The study sample comprised 20 MRI negative epilepsy patients [mean age ± standard deviation (SD), 30.3 ± 12.56 years; age range 16-60 years; average disease duration, 13.95 years) and 10 age-matched controls (mean age ± SD, 24.22 ± 15.39 years), that were also education-matched (p>0.05) Patients with epileptogenic lesions were excluded from the study. Informed consent was obtained from all subjects involved in the study. Auditory ERPs and the cognitive screening tool EpiTrack, were administered to all subjects. Results: Latencies of P300 and slow waves were prolonged in patients compared to controls (p<0.05). ASM load and the patients’ performance in the EpiTrack maze subtest were the most significant predictors of P300 latency. A decline in memory, attention, and speed of information processing has been observed in patients with cryptogenic epilepsy compared to age-matched controls, as reflected by P300 latency and EpiTrack scores.
ARTICLE | doi:10.20944/preprints202107.0706.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: epilepsy; glutamatergic transmission; glutamine synthesis; methionine sulfoximine; metabolomics
Online: 30 July 2021 (14:26:35 CEST)
Pretreatment with non-convulsive dose of methionine sulfoximine (MSO) attenuated lithi-um-pilocarpine-induced (Li-Pilo) seizures in young rats . We hypothesized that the effect of MSO results from a) glutamine synthetase block-mediated inhibition of conversion of Glu/Gln precursors to neurotransmitter Glu, and/or from b) altered synaptic Glu release. Pilo was admin-istered 60 min prior to sacrifice, MSO at 75 mg/kg, i.p., 2.5 h earlier. [1,2-13C]acetate and [U-13C]glucose were i.p.-injected either together with Pilo (onset) or 15 min before sacrifice (final phase). Their conversion to Glu and Gln in hippocampus and entorhinal cortex was followed us-ing [13C] gas chromatography-mass spectrometry. Release of in vitro loaded [3H]D-Asp from ex vi-vo brain slices was measured in continuously collected superfusates. Protein and mRNA expres-sion were measured by Western Blot and real-time PCR techniques, respectively. At no time point nor brain region did MSO modify incorporation of [13C] to Glu or Gln in Pilo-treated rats. MSO pretreatment decreased by ~37% high potassium-induced [3H]D-Asp release and reduced by ~50% the synaptic vesicular Glu transporter VGLUT1 protein, but not mRNA content in the hippo-campus. The results indicate that MSO at non-convulsive dose mitigates the initial Pilo-induced seizures by interfering with synaptic Glu-release but not with neurotransmitter Glu recycling.
REVIEW | doi:10.20944/preprints202105.0317.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Medial septum; Oscillation; Oscillopathy; Deep brain stimulation; Epilepsy
Online: 14 May 2021 (08:44:10 CEST)
The medial septum (MS), as part of the basal forebrain, supports many physiological functions, from sensorimotor integration to cognition. With often reciprocal connections with a broad set of peers at all major divisions of the brain, the MS orchestrates oscillatory neuronal activities throughout the brain. These oscillations are critical in generating sensory and emotional salience, locomotion, maintaining mood, supporting innate anxiety, and governing learning and memory. Accumulating evidence points out that the physiological oscillations under septal influence are frequently disrupted or altered in pathological conditions. Therefore, the MS may be a potential target for treating neurological and psychiatric disorders with abnormal oscillations (oscillopathies) to restore healthy patterns or erase undesired ones. Recent studies have revealed that the patterned stimulation of the MS alleviates symptoms of epilepsy. We discuss here that stimulus timing is a critical determinant of treatment efficacy on multiple time scales. On-demand stimulation may dramatically reduce side effects by not interfering with normal physiological functions. A precise pattern-matched stimulation through adaptive timing governed by the ongoing oscillations is essential to effectively terminate pathological oscillations. The time-targeted strategy for the MS stimulation may provide an effective way of treating multiple disorders including Alzheimer’s disease, anxiety/fear, schizophrenia, and depression, as well as pain.
ARTICLE | doi:10.20944/preprints202104.0135.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Onchocerciasis; Onchocerca volvulus; epilepsy; nodding syndrome; prevalence; ivermectin
Online: 5 April 2021 (12:53:07 CEST)
In June 2020, a door-to-door household survey was conducted in Mvolo County, an onchocerciasis endemic area in South Sudan. A total of 2,357 households containing 15,699 individuals agreed to participate in the study. Of these, 5,046 (32.1%, 95%CI: 31.4-32.9%) had skin itching and 445 (2.8%, 95% CI: 2.6-3.1%) were blind. An epilepsy screening questionnaire identified 813 (5.1%) persons suspected to have epilepsy. Of them, 804 (98.9%) were seen by a medical doctor and in 798 (98.1%) the diagnosis of epilepsy was confirmed. The overall epilepsy prevalence was 50.8/1000 (95% CI: 47.6-54.4/1000) and prevalence of nodding syndrome was 22.4/1000 (95% CI: 20.1-24.9/1000). Younger age, being male, skin itching, blindness and living in a village close to the Naam river were risk factors for epilepsy. The annual incidence of epilepsy was 82.8/100,000 (95% CI: 44.1-141.6/100,000). In conclusion, a high prevalence and incidence of epilepsy was observed in Mvolo, South Sudan. Strengthening the onchocerciasis elimination programme is urgently needed to prevent epilepsy in this region.
CASE REPORT | doi:10.20944/preprints202011.0386.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: Precision diagnosis; Personalised interventions; Temporal lobe epilepsy (TLE)
Online: 13 November 2020 (14:15:57 CET)
A 12 year old boy was diagnosed with temporal lobe epilepsy (TLE) along with mesial temporal sclerosis based on MRI (magnetic resonance imaging) results. The diagnosis was further confirmed by genetic analysis. He also had minor psychiatric symptoms of obsessive-compulsive disorders and mood swings. After 4 years of treatment with Sodium Valproate no change in symptoms was observed. Genetic testing along with deep phenotyping revealed altered glutamate pathway and metabolism. Post genetic testing the patient was put on a combination of Sodium Valproate and Valproic acid along with supplementation of N-acetylcysteine (NAC), Cyanocobalamin, Pyridoxine and Cholecalciferol. Within three months of this combined therapy the patient experienced complete elimination of seizures and drastic improvement in mood and social behaviour. The case report highlights the importance of precision diagnosis in understanding the underlying perturbed pathways in structural epilepsy like TLE and demonstrates the importance of non-invasive targeted therapy in such cases.
REVIEW | doi:10.20944/preprints202212.0046.v1
Subject: Biology And Life Sciences, Biophysics Keywords: oscillations, theta rhythm, gamma rhythm, coherence, temporal lobe epilepsy
Online: 2 December 2022 (10:11:23 CET)
The dentate gyrus (DG) is part of the hippocampal formation and is essential for important cognitive processes such as navigation and memory. The oscillatory activity of the DG network is believed to play a critical role in cognition. DG circuits generate three main rhythms: theta, beta, and gamma, which participate in the specific information processing performed by DG neurons. In the temporal lobe epilepsy (TLE), cognitive abilities are impaired, which may be due to drastic alterations in the DG structure and network activity during epileptogenesis. The theta rhythm and theta coherence are especially vulnerable in dentate circuits; disturbances in DG theta oscillations and their coherence may be responsible for general cognitive impairments observed during epileptogenesis. Some researchers suggested that the vulnerability of DG mossy cells is a key factor in the genesis of TLE, but others did not support this hypothesis. The aim of the review is not only to present the current state of the art in this field of research but to help pave the way for future investigations by highlighting the gaps in our knowledge to completely appreciate the role of DG rhythms in brain functions. Disturbances in oscillatory activity of the DG during TLE development are described in detail that may be a diagnostic marker in the treatment of this disease.
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: cannabinoid receptor 2; epilepsy; cAMP, M-current; anti-inflammatory
Online: 6 July 2021 (17:09:20 CEST)
Epilepsy is characterized by repeated spontaneous reactions caused by hyper-excitability and neurons firing in high synchronization in the central nervous system. It seriously affects the quality of life of epileptic patients and nearly 30% of individuals are refractory to treatment of antiepileptic drugs. Therefore, there is an urgent need to develop new medicines to manage and control the refractory epilepsy. Cannabinoid ligands including selective cannabinoid receptor subtype (CB1 or CB2 receptor) ligands and non-selective cannabinoid (synthetic and endogenous) ligands may serve as the novel candidates for this need. Cannabinoid systems appear to regulating seizure activity in the brain through the activation of CB1 and CB2 cannabinoid receptors (CB1R and CB2R). An abundant series of cannabinoid analogues have been tested in various animal models, including a rat pilocarpine model of acquired epilepsy, in vitro hippocampal neuronal culture models of acquired epilepsy and status epilepticus, a pentylenetetrazole model of myoclonic seizures in mice and a penicillin-induced model of epileptiform activity in the rats. The accumulating lines of evidence show that cannabinoid ligands exhibit significant benefits to control seizure activity in different epileptic models. For this reason, we summarize the relationship between brain CB2 receptors and seizures, and emphasize the potential mechanisms of their therapeutic effects involving affecting neurons, astrocytes, and microglia cells. The unique features of CB2Rs, such as lower expression levels under physiological conditions and high inducibility under epileptic conditions, make it an important target for future research on drug-resistant epilepsy.
REVIEW | doi:10.20944/preprints202104.0043.v1
Subject: Arts And Humanities, Theater Keywords: Epilepsy, Theatre, Neurology, Cultural History, Drama, Engagement, Medical Communication
Online: 2 April 2021 (11:12:17 CEST)
The theatre has a tremendous ability to influence public discourse and shape societal opinions. And medical conditions can provide writers with a rich scope for plot development and characters with challenges to overcome. In particular, the neurological condition epilepsy has many possibilities with historical beliefs that people were possessed by gods and devils and the sudden, disabling seizures characteristic of the condition. But used unsympathetically, it can promote misunderstanding within audiences, resulting in discrimination for people with the condition. This review looks back at how epilepsy has been portrayed throughout history. How the Greeks portrayed epilepsy as a punishment from the gods. Then later, how Shakespeare utilised epilepsy to suggest characters as uncontrollable. However, we finish on a message of hope as modern writers look to collaboration to ensure accurate and honest portrayals of epilepsy, improving public understanding and removing many of the stigmas that have dogged the condition.
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: nNOS; Temporal lobe epilepsy; Interneuron; Synaptic transmission; Mouse models
Online: 25 November 2020 (10:19:05 CET)
Excitation-inhibition imbalance of GABAergic interneurons is predisposed to develop chronic temporal lobe epilepsy (TLE). We have previously shown that virtually every neuronal nitric oxide synthase (nNOS)-positive cell is a GABAergic inhibitory interneuron in the denate gyrus. The present study was designed to quantify the number of nNOS-containing hilar interneurons using stereology in pilocapine- and kainic acid (KA)-exposed transgenic adult mice that expressed GFP under the nNOS promoter. In addition, we studied the properties of miniature excitatory postsynaptic current (mEPSC) and paired-pulse response ratio (PPR) of evoked EPSC in nNOS interneurons using whole cell recording techniques. Results showed that there were fewer nNOS-immunoreactive interneurons of chronically epileptic animals. Importantly, patch-clamp recordings revealed reduction in mEPSC frequency, indicating diminished global excitatory input. In contrast, PPR of evoked EPSC following the granule cell layer stimulation was increased in epileptic animals suggesting reduced neurotransmitter release from granule cell input. In summary, we propose that impaired excitatory drive onto hippocampal nNOS interneurons may be implicated in the development of refractory epilepsy.
Subject: Medicine And Pharmacology, Pathology And Pathobiology Keywords: Epilepsy; Brain damage; Golgi determinations; Ramon y Cajal: axons
Online: 27 March 2020 (12:35:20 CET)
As a medical student (Granada University Medical School, Spain), interested in Pediatrics, expended countless hours at the hospital pediatric facilities and got to know many of the children and their medical problems. A particular case, still vivid on my mind, awaken my scientific curiosity. One day, walking and talking with a seven years old child he unexpectedly felt down unconscious with multiple, incontrollable and erratic muscular contractions involving face, body and extremities and salivating. I was overwhelmed thinking it was the child’ last hour. At the time, my knowledge of epilepsy was nil. Following the seizures, the child was up, talking and walking with me as if nothing has happened and without any knowledge of the event. What could have caused the brain motor cortex to suddenly discharge that amount of altered activity causing generalized and erratic muscular contractions remains inexplicable. I migrated to USA, become a Pediatric (Developmental) Pathologist and Director of the Pediatrics Autopsy Service (1962-1999) at the Dartmouth-Hitchcock Medical Center, New Hampshire. I carried out countless postmortem studied of children brains, normal (unaltered) as well as those altered by hemorrhagic, hypoxic-ischemic and/or traumatic damage. With an NIH Fellowship, I spend one year (1967-68) at the Cajal Institute (Madrid, Spain) studying Cajal’ old Golgi preparations and learning about the method. Some of my Golgi studies of children’ brains have been published: The Human Brain. Prenatal Development and Structure, Springer, Heidelberg, Germany, 2012. The present monograph explores the developmental neuropathology of selected perinatal cortical injuries through their acute, subacute and chronic stages. Including: a) how an altered neuronal activity evolves in a damaged cortical region; b) how it moves through the cortex (epileptic auras); and c) how it reaches the motor cortex to be discharged as erratic and incontrollable muscular contractions. Understanding these processes should provide insights into the pathogenesis of epilepsy secondary to perinatal brain damage.
REVIEW | doi:10.20944/preprints202311.1719.v1
Subject: Medicine And Pharmacology, Clinical Medicine Keywords: Dravet Syndrome; developmental epileptic encephalopathy; genetics; targeted therapy; epilepsy syndrome
Online: 28 November 2023 (08:12:09 CET)
Dravet syndrome (DS), also known as severe myoclonic epilepsy of infancy, is a rare and drug-resistant form of developmental and epileptic encephalopathies, which is both debilitating and challenging to manage, typically arising during the first year of life, with seizures often triggered by fever, infections, or vaccinations. It is characterized by frequent and prolonged seizures, developmental delays, and various other neurological and behavioral impairments. Most cases result from pathogenic mutations in the sodium voltage-gated channel alpha subunit 1 (SCN1A) gene, which encodes a critical voltage-gated sodium channel subunit involved in neuronal excitability. Precision medicine offers significant potential for improving DS diagnosis and treatment. Early genetic testing enables timely and accurate diagnosis. Advances in our understanding of DS's underlying genetic mechanisms and neurobiology have enabled the development of targeted therapies, such as gene therapy, offering more effective and less invasive treatment options for patients with DS. Targeted and gene therapies provide hope for more effective and personalized treatments. However, research into novel approaches remains in its early stages, and their clinical application remains to be seen. This review addresses the current understanding of clinical DS features, genetic involvement in DS development, and outcomes of novel DS therapies.
ARTICLE | doi:10.20944/preprints202307.1606.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: FH; RF; KNN; CHB-MIT; TUHEEG; EEG; Epilepsy; Seizure stages
Online: 25 July 2023 (03:25:03 CEST)
Electroencephalography (EEG) is essential for tracking brain activity and identifying seizure effects. However, epileptic behaviour can only be detected after a specialist has carefully analysed all EEG recordings along with a proper history of the patient. A skilled physician is required for the right epilepsy diagnosis and therapy. But most of the time, patients visit the clinician in the interictal stage with no proper history documented. Therefore, it was essential to the automatic prediction of stages of seizure. K nearest neighbours (KNN) and random forest (RF) models using raw EEG signals, preictal, ictal, postictal, and interictal stages were identified in this study. The possibility of these characteristics is explored by examining how well time-domain signals work in the prediction of epileptic stages using intracranial EEG datasets from Freiburg Hospital (FH), Children's Hospital Boston-Massachusetts Institute of Technology (CHB-MIT), and Temple University Hospital (TUHEEG). To test the viability of this approach, two different types of simulations were carried out on three binary classifications (interictal vs. preictal, interictal vs. ictal, preictal vs. postictal, and interictal vs. postictal), and one four-class problem (interictal vs. preictal vs. ictal vs. postictal) was performed for each model. The average accuracy when using time-domain signals in the FH database was 90.5% and 75.0%; CHB-MIT was 92.87% and 75.9%; and TUHEEG was 94.46% and 76.8%, respectively, for the KNN and RF models.
ARTICLE | doi:10.20944/preprints202306.1970.v1
Subject: Biology And Life Sciences, Life Sciences Keywords: Atp6v1b2; R506*; mice; locomotor hyperactivity; diminished anxiety-related behavior; epilepsy
Online: 28 June 2023 (08:34:11 CEST)
The vacuolar H+-ATPase is a multisubunit enzyme which plays an essential role in the acidification and functions of lysosomes, endosomes, and synaptic vesicles. Many genes encoding subunits of V-ATPases, namely ATP6V0C, ATP6V1A, ATP6V0A1 and ATP6V1B2, have been associated with neurodevelopmental disorders and epilepsy. The autosomal dominant ATP6V1B2 p.Arg506* variant can cause both deafness, congenital, with onychodystrophy, autosomal dominant (DDOD) and deafness, onychodystrophy, osteodystrophy, mental retardation, and seizures syndromes (DOORS). Some but not all individuals with this truncating variant have intellectual disability and/or epilepsy, suggesting incomplete penetrance and/or variable expressivity. To further explore the impact of the p.Arg506* variant in neurodevelopment and epilepsy, we generated Atp6v1b2emR506* mutant mice and performed standardized phenotyping using the International Mouse Phenotyping Consortium (IMPC) pipeline. In addition, we assessed the EEG profile and seizure susceptibility of Atp6v1b2emR506* mice. Behavioral tests revealed that the mice present locomotor hyperactivity and show less anxiety-associated behaviors. Moreover, EEG analyses indicate that Atp6v1b2emR506* mutant mice have interictal epileptic activity and that both heterozygous (like patients) and homozygous mice have reduced seizure thresholds to pentylenetetrazol. Our results confirm that variants in ATP6V1B2 can cause seizures and that the Atp6v1b2emR506* heterozygous mouse model is a valuable tool to further explore the pathophysiology and potential treatments for vacuolar ATPases-associated epilepsy and disorders.
HYPOTHESIS | doi:10.20944/preprints202305.0064.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: VNS; temporal lobe epilepsy; vagus nerve; interoception; hippocampus; medial septum
Online: 2 May 2023 (07:05:43 CEST)
Seizure development relies on two factors. One is the existence of an overexcitable neuronal network and the other is a trigger that switches normal activity of that network into a paroxysmal state. While mechanisms of local overexcitation have been the focus of many studies, the process of triggering remains poorly understood. We suggest that, apart from the known exteroceptive sources of reflex epilepsy – visual, auditory or olfactory, there is a range of interoceptive triggers, relevant for seizure development in Temporal Lobe Epilepsy (TLE). The hypothesis proposed here aims to explain the prevalence of epileptic activity in sleep and in drowsiness states and provide a detailed mechanism of seizure triggering by interoceptive signals.
ARTICLE | doi:10.20944/preprints202203.0114.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: epilepsy; Responsive Neurostimulation; wireless transmission; BLE; Delta encoding; low power
Online: 8 March 2022 (02:16:09 CET)
This research refers to the creation of a method of medical technology such as a device that can collect, encode, temporarily store, and transfer electroencephalographic signals from epileptic patients for study and evaluation. For applying the specific apparatus related to neurostimulation technologies such as Deep Brain Stimulation (DBS) and Responsive Neurostimulation (RNS) the approaches followed concern three basic levels. The first level is concerned with initial modelling and creating the template for the following two stages. Further on, the second level is based on developing code for programming integrated circuits and simulation with the appropriate software. The third and final stage is the most substantial, as the transmitter’s construction is attempted at the evaluation level. In particular, more than one software and device are involved in this phase for the most realistic performance of the desired result. However, it is worth noting that the principal goal of this study is to achieve low consumption rates for the device’s complete and smooth operation. As a result, this research aims to evolve this device so that it can send data wirelessly and simultaneously provide energy efficiency.
ARTICLE | doi:10.20944/preprints202107.0416.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: Epilepsy; VOCs; Attention seeking behaviours; Remote Odour Delivery Mechanism (RODM)
Online: 19 July 2021 (14:30:08 CEST)
Abstract Epilepsy is a disorder of the brain and a seriously debilitating condition, which has been associated with injury, social stigmatisation and in some cases, sudden unexpected and premature death. A sense of profound isolation is felt by many individuals with epilepsy, and this community has expressed an urgent desire for an early warning system to allow them time to prepare for seizure onset. Surveys of dog owners with epilepsy have previously reported that some dogs can predict the onset of a seizure. The current study used an experimental design to investigate the alleged propensity of untrained pet dogs to react to human epileptic seizures. We hypothesised that seizures are associated with specific volatile organic compounds resulting in detectable odours which are the biomarker that triggers these reported behavioural changes in the dogs. Here we provide details of the first empirical test to demonstrate that pet dogs display several significant behavioural changes when they are exposed to seizure-related odours that apparently emanate from their owners. Using a repeated measures design experiment, recordings were made of the reactions of 19 untrained pet dogs to odours from sweat samples provided by three people with epilepsy and by two people without epilepsy (controls). The seizure-associated sweat samples were captured pre-seizure, during seizure and post-seizure. All samples were randomly delivered to individual dogs in a test area, using two bespoke pieces of apparatus called Remote Odour Delivery Mechanisms (RODM). One RODM delivered only experimental odours, the other delivered only control odours. Behavioural changes by the dogs on encountering the odour samples were recorded by video for later analysis. Consistent with our hypothesis, seizure-associated odours evoked significant behavioural changes in the dogs which were affiliative in nature and directed at their owners.
REVIEW | doi:10.20944/preprints202102.0478.v2
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: epilepsy; computational model; seizures; single neurons level; networks; whole brain
Online: 16 June 2021 (12:14:49 CEST)
Dynamical system tools offer a complementary approach to detailed biophysical seizure modeling, with a high potential for clinical applications. This review describes the theoretical framework that provides a basis for theorizing certain properties of seizures and for their classification according to their dynamical properties at onset and offset. We describe various modeling approaches spanning different scales, from single neurons to large-scale networks. This narrative review provides an accessible overview of this field, including non-exhaustive examples of key recent works.
ARTICLE | doi:10.20944/preprints202003.0292.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: temporal lobe epilepsy; antioxidants; oxidative stress; neuroimmune; major depression; schizophrenia
Online: 19 March 2020 (02:11:32 CET)
Background: Temporal lobe epilepsy (TLE) is the most common focal epilepsy subtype in adults and is frequently accompanied by depression, anxiety and psychosis. Aberrations in total paraoxonase (PON)1 status may occur in TLE and those psychiatric conditions. Methods: We examined paraoxonase (PON)1 status, namely Q192R PON1 genotypes and PON1 enzymatic activities, in 40 normal controls and 104 TLE patients, 27 without comorbidities, and 77 with comorbidities including mood disorders (n=25), anxiety disorders (n=27) and psychosis (n=25). Outcomes: CMPAase and arylesterase activities were significantly lower in TLE and mesial temporal sclerosis (MTS) with and without psychiatric comorbidities than in normal controls. The areas under the ROC curve of CMPAase were 0.893 (0.037) for TLE and 0.895 (±0.037) for MTS. Partial Least Squares (PLS) path analysis showed that there were specific indirect effects of PON1 genotype on TLE severity (p<0.0001) and psychopathology (p<0.0001), which were both mediated by lowered CMPAase activity, while arylesterase activity was not significant. The severity of TLE was significantly associated with psychopathology scores. Furthermore, PON1 CMPAase activity was inversely associated with Mini Mental State Examination scores. Interpretation: The severity of TLE and comorbidities are to a large extent explained by lowered PON1 enzyme activities and by effects of the Q192R genotype which are mediated by lowered CMPAase activity. Total PON1 status plays a key role in the pathophysiology of TLE, MTS and psychiatric comorbidities by increasing the risk of oxidative toxicity. PON1 enzyme activities are new drug targets in TLE to treat seizure frequency and psychiatric comorbidities.
ARTICLE | doi:10.20944/preprints202306.0623.v1
Subject: Engineering, Bioengineering Keywords: Epilepsy; Electroencephalogram; Convolutional neural networks; Brain signal integral; Brain signal derivative
Online: 8 June 2023 (10:13:28 CEST)
Epilepsy is a neurological disorder that affects approximately 1% of the world's population. To diagnose and estimate the occurrence of epilepsy, the analysis of recorded brain activity is performed by a neurologist, which is not only time-consuming and tedious but also occasionally accompanied by human error. Therefore, in recent decades, researchers have aimed to unravel an approach for designing and building an automated method for diagnosing and estimating the occurrence of epilepsy. Accordingly, the present study proposed two new-fangled ways based on brain signals and a convolutional neural network (CNN). Moreover, this research implements a CNN with a sequential three-layer structure. Numerous experiments were performed, and the accuracy of estimating epilepsy using the developed methods was achieved at 95% without feedback and 97% with feedback. The proposed methods were proven to be more accurate than the previous techniques and can be employed as a physician's assistant once entering the field of operation.
ARTICLE | doi:10.20944/preprints201912.0382.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: glioblastoma multiforme; MGMT; IDH1; EGFR; P53; ATRX; Ki67; neurosurgery; oncology; epilepsy
Online: 29 December 2019 (13:04:12 CET)
Glioblastoma is a solid, infiltrating and the most frequent highly malignant primary brain tumor. Our aim was to find the prognostic value of mutations of IDH1, MGMT, EGFR, p53, ATRX, Ki67 genes and the correlation between sex, age, presenting with seizures, number of interventions, extent of resection with Overall Survival (OS), Progression Free Survival (PFS) and Karnofsky performance status (KPS) score. A randomized retrospective analysis of 122 patients treated by a single operator at Sapienza University of Rome, was carried out. After surgery patients followed standard treatment Stupp protocol . Exclusion criteria were: patients with primitive brainstem and spinal cord gliomas and patients who underwent partial resections (resection < 90%) and cases of brain biopsy exclusively for diagnostic purposes. Statistical analysis with a simultaneous regression model was carried on by SPSS 25 ® (IBM) program. Results showed statistically significant survival increase in four groups: 1) patients treated with gross total resection (p< 0.03); 2) patients with methylated MGMT promoter (p<0.005); 3) patients with non EGFR amplification or EGFRvIII mutation (p<0.035); 4) mutated IDH1/IDH2 (p<0.0161). Higher survival rates (but not statistically significant) were observed also in patients with: age < 75 years, Ki 67 <10%, lesions in non eloquent areas, ATRX gene mutation and presentation with seizures.
ARTICLE | doi:10.20944/preprints202306.1010.v1
Subject: Medicine And Pharmacology, Dietetics And Nutrition Keywords: Adherence; patient compliance; ketogenic diet; epilepsy; Glut1 deficiency; Treatment Adherence and Compliance
Online: 14 June 2023 (07:58:49 CEST)
Ketogenic dietary therapies (KDTs) are an effective and safe non-pharmacological treatment for drug-resistant epilepsy, but adherence can be challenging for both patients and caregivers. In Europe, there are no adequate tools to measure it other than monitoring ketosis. This study aimed to adapt and validate the Brazilian adherence questionnaire, Keto-check, into the Italian version: iKetoCheck. Using the Delphi technique, 12 judges validated the contents through agreement rate and the Content Validity Index (CVI). The iKetocheck was self-completed electronically by drug-resistant epilepsy or GLUT1 deficiency patients within an interval of 15 days to measure its reproducibility. Test-retest reliability was evaluated using Pearson correlation and relative significance test. Exploratory and confirmatory factorial analyses were made using Factor software. The final tool, iKetoCheck, consists of 10 questions with 5-point Likert scale answers. It evaluates various aspects such as informing caregivers about the diet, organization of meals, measurement of ketosis, weighing food consumed, diet negligence, use of carbohydrate-free medications, attending follow-up visits, reading food labels, consulting an expert for dietary concerns, and cooking at home. The factorial analysis resulted in three factors: "attention," "organization," and "precision," with satisfactory results for indices in exploratory and confirmatory analyses. Although higher mean values of ketonemia measurement were observed in patients with a higher adherence score, these values were not statistically significant (p=0.284). In conclusion, iKetoCheck is a valid tool for evaluating KDTs' adherence in Italian drug-resistant epilepsy or GLUT1 deficiency patients. It can provide valuable information to improve patient management and optimize the effectiveness of KDTs.
REVIEW | doi:10.20944/preprints202304.1118.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: KCNA1; Kv1.1; epilepsy; episodic ataxia; myokymia; SUDEP; respiration; genetic modifiers; musculoskeletal; nystagmus
Online: 28 April 2023 (04:59:32 CEST)
The KCNA1 gene encodes Kv1.1 voltage-gated potassium channel α subunits, which are crucial for maintaining healthy neuronal firing and preventing hyperexcitability. Mutations in the KCNA1 gene can cause several neurological diseases and symptoms, such as episodic ataxia and epilepsy, which may occur alone or in combination, making it challenging to establish simple genotype-phenotype correlations. Previous analyses of human KCNA1 variants have shown that epilepsy-linked mutations tend to cluster in regions critical for the channel’s pore, whereas EA1-associated mutations are evenly distributed across the length of the protein. In this review, we examine 17 recently discovered pathogenic or likely pathogenic KCNA1 variants to gain new insights into the molecular genetic basis of KCNA1 channelopathy. We provide the first systematic breakdown of disease rates for KCNA1 variants in different protein domains, uncovering potential location biases that influence genotype-phenotype correlations. Our examination of the new mutations strengthens the proposed link between the pore region and epilepsy and reveals new connections between epilepsy-related variants, genetic modifiers, and respiratory dysfunction. Additionally, the new variants include the first two gain-of-function mutations ever discovered for KCNA1, the first frameshift mutation, and the first mutations located in the cytoplasmic N-terminal domain, broadening the functional and molecular scope of KCNA1 channelopathy. Moreover, the recently identified variants highlight emerging links between KCNA1 and musculoskeletal abnormalities and nystagmus, conditions not typically associated with KCNA1. These findings improve our understanding of KCNA1 channelopathy and promise to enhance personalized diagnosis and treatment for individuals with KCNA1-linked disorders.
ARTICLE | doi:10.20944/preprints202207.0366.v1
Subject: Medicine And Pharmacology, Tropical Medicine Keywords: onchocerciasis; community directed treatment with ivermectin; elimination; epilepsy; focus group discussions; misconceptions
Online: 25 July 2022 (09:27:22 CEST)
Despite of over 20 years of community directed treatment with ivermectin (CDTI), a high prevalence of onchocerciasis and onchocerciasis-associated epilepsy were observed in rural villages in Mahenge, Tanzania. Therefore, we assessed the knowledge, attitude and practice about onchocerciasis in four rural villages in the Mahenge area. This was a qualitative study conducted between June and July 2019. Eleven focus group discussions were organized with persons with epilepsy and their caretakers, community resource persons, and community drug distributors (CDDs), and two in-depth interviews with district programme coordinators of neglected tropical diseases (NTD). Most participants were aware about symptoms of onchocerciasis using local terminologies such as “ukurutu/rough dry skin” and “kuwashwa/itching”. A small proportion of people did not take ivermectin during CDTI for fear of adverse reactions such as itching and swelling. Some men believed that ivermectin may decrease libido. Challenges for high CDTI coverage included, long walking distance by CDDs to deliver drugs to households, persons being away for farming, low awareness of the disease and limited supervision by the NTD coordinators. In conclusion, ivermectin uptake in Mahenge should be optimised by continuous advocacy about the importance of taking ivermectin to prevent onchocerciasis-associated morbidity and by improving supervision during CDTI.
ARTICLE | doi:10.20944/preprints202203.0314.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: metabolomics; antiseizure medication; ¹H Nuclear Magnetic Resonance; focal epilepsy; response to treatment
Online: 23 March 2022 (09:11:52 CET)
A major challenge in the clinical management of patients with mesial temporal lobe epilepsy (MTLE) is identifying those who do not respond to antiseizure medication (ASM), allowing for the timely pursuit of alternative treatments, such as epilepsy surgery. Here, we investigated changes in plasma metabolites as biomarkers of pharmacoresistance in patients with MTLE. Furthermore, we used the metabolomics data to gain insights into the mechanisms underlying MTLE and response to ASM. We performed an untargeted metabolomic method using magnetic resonance spectroscopy and multi- and univariate statistical analyses to compare data obtained from plasma samples of 28 patients with MTLE compared to 28 controls. The patients were further divided according to response to ASM: 20 patients were refractory to treatment, and eight were responsive to ASM. We only included patients using carbamazepine in combination with clobazam. We compared the group of patients with controls and found that the profiles of glucose (p = 0.01), saturated lipids (p = 0.0002), isoleucine (p = 0.0001), β-hydroxybutyrate (p = 0.0003), and proline (p = 0.02) were different in patients compared to controls (p < 0.05). In addition, lipoproteins (p = 0.05), lactate (p = 0.05), glucose (p = 0.05), unsaturated lipids (p = 0.05), isoleucine (p = 0.05), and proline (p = 0.05), could discriminate between the two groups of patients classified according to response to ASM. The identified metabolites were linked to different biological pathways related to cell energy metabolism, and pathways linked to inflammatory processes and the modulation of neurotransmitter release and activity in MTLE. In contrast, we found that pyruvate metabolism may be linked to resistance to ASM. In conclusion, in addition to insights into the mechanisms underlying MTLE and the response to treatment with ASM, our results suggest that plasma metabolites may be used as biomarkers of disease and response to ASM in patients with MTLE. These findings warrant further studies exploring the clinical use of metabolites to assist in decision-making when treating patients with MTLE.
REVIEW | doi:10.20944/preprints202108.0513.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: liquid biopsy; epilepsy; circulating biomarkers; cfDNA; lncRNA; tRNA; miRNA; diagnosis; prognosis; therapeutics
Online: 26 August 2021 (16:40:54 CEST)
Epilepsy is one of the most common disorders of the central nervous system, impacting nearly 50 million people around the world. Heterogeneous in nature, epilepsy presents in children and adults alike. Currently, surgery is the only treatment that can cure epilepsy. However, not all individuals are eligible or have successful outcomes. Difficulty in accessing samples of human brain tissue along with advances in sequencing technology have driven researchers to investigate sampling liquid biopsies in blood, serum, plasma, and cerebrospinal fluid within the context of epilepsy. Liquid biopsies provide minimal or non-invasive sample collection approaches and can be assayed relatively easily across multiple time points, unlike tissue-based sampling. Various efforts have investigated circulating nucleic acids from these samples including microRNAs, cell-free DNA, transfer RNAs, and long non-coding RNAs. Here, we review nucleic acid-based liquid biopsies in epilepsy to improve understanding of etiology, diagnosis, prediction, and therapeutic monitoring.
CASE REPORT | doi:10.20944/preprints202008.0502.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: KARS gene; aminoacylation; leucodistrophy; epilepsy; hearing loss developmental delay; whole exome sequencing
Online: 24 August 2020 (03:10:45 CEST)
The KARS gene encodes the aminoacyl-tRNA synthetase (aaRS) which activates and joins the lysin with its corresponding transfer RNA (tRNA), through the ATP-dependent aminoacylation of the amino acid. The KARS gene mutations have been linked to diverse neurologic phenotypes such as: neurosensorial hearing loss, leukodistrophy, microcephaly, developmental delay or regression, peripheral neuropathy, cardiomyopathy, impairment of the mitochondrial respiratory chain, hyperlactatemia, among others. This article presents the case of a Colombian pediatric patient with two pathological missense variants in a compound heterozygous state in the KARS gene.
ARTICLE | doi:10.20944/preprints202311.0289.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: febrile seizures; hypertherippocampmia; hus; maximal electroshock seizure threshold test; epilepsy; local field potential
Online: 6 November 2023 (07:33:11 CET)
Febrile seizures in early childhood can lead to developmental disorders in the CNS. However, the specific mechanisms behind the impact of febrile seizures on the developing brain are not well-understood. To address this gap in knowledge, we employed a hyperthermic model of febrile seizures in 10-day-old rats and tracked their development over two months. Our objective was to determine the degree to which the properties of the hippocampal glutamatergic system are modified. We analyzed whether pyramidal glutamatergic neurons in the hippocampus die after febrile seizures. Our findings indicate that there is a reduction in the number of neurons in various regions of the hippocampus in the first two days after seizures. The CA1 field showed the greatest susceptibility, and the reduction in the number of neurons in post-FS rats in this area appeared to be long-lasting. Electrophysiological studies indicate that febrile seizures cause a reduction in glutamatergic transmission, leading to decreased local field potential am-plitude. This impairment could be attributable to diminished glutamate release probability as evidenced by decreases in frequency of miniature excitatory postsynaptic currents and increases in pair-pulse ratio of synaptic responses. We also found higher threshold current causing hindlimb extension in the maximal electroshock seizure threshold test of rats 2 months after febrile seizures compared to control animals. Our research suggests that febrile seizures can impair glutamatergic transmission, which may protect against future seizures.
ARTICLE | doi:10.20944/preprints202308.0238.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: VMAT; stereotactic radiosurgery; brain tumor-related epilepsy; overall survival; brain metastasis; brain location
Online: 2 August 2023 (16:01:27 CEST)
Whole-brain radiation therapy and stereotactic radiosurgery are two treatment modalities commonly utilized to treat brain metastases (BMs). The aim of this study is to retrospectively analyze the main radio-oncologic and clinical-demographic aspects of a cohort of BM patients treated with Volumetric Modulated Arc Therapy for radiosurgery (VMAT-RS). This is a cross-sectional observational design study with retrospective review of medical records of patients with brain metastases treated with VMAT- RS between 2012 and 2018. Clinical and demographic data, with special attention to sex, age, primary tumor, brain tumor-related epilepsy (BTRE), number and brain location of BMs, Karnofsky Performance Status (KPS), the updated DS-GPA prognostic index and the survival estimated according to the Kaplan-Meier model from the date of radiosurgery were analyzed. One hundred and twenty-one patients with 229 BMs were treated with VMAT-RS. Patients presented 1-4 BMs, which were treated with 5 non-coplanar VMAT arcs. Sixty-eight percent of the patients had lung cancer and 35% of the BMs were in the frontal lobe. Proportion of local control was 88.5%. BTRE prevalence was 30.6%. The median survival time (MST) was 7.7 months. In the multivariate analysis of the Cox Regression model KPS70 (HRKPS<70=2.59; p=0.001) and higher DS-GPA (HRDS-GPAII =0.55, p=0.022; HRDS-GPAIII-IV =0.38, p=0.006) were associated with improved survival. In the univariate analysis, primary tumor, age and the presence of metastases in the posterior fossa (PFBMs) were also significative. In conclusion, the VMAT-RS is a technique with an overall survival comparable to other radiosurgery techniques. The median survival is significantly longer in those with higher KPS and DS-GPA. Other variables such as the type of primary tumor, age and PFBMs could also influence survival, although further studies are needed.
REVIEW | doi:10.20944/preprints202007.0373.v1
Subject: Medicine And Pharmacology, Psychiatry And Mental Health Keywords: autism spectrum disorder; cannabinoids; cannabidiol; cannabidivarin; THC; problem behaviors; sleep; epilepsy; side effects.
Online: 17 July 2020 (09:19:13 CEST)
The etiopathogenesis of autism spectrum disorder (ASD) remains largely unclear. Among other biological hypotheses, researchers have evidenced an imbalance in the endocannabinoid (eCB) system, which regulates some functions typically impaired in ASD, such as emotional responses and social interaction. Also, cannabidiol (CBD), the non-intoxicating component of Cannabis sativa, has been recently approved for treatment-resistant epilepsy. Seizures represent frequent medical comorbidities of ASD and could be responsible for the onset or worsening of behavioral problems. Thus, it has been hypothesized that cannabinoids could be useful in improving some ASD symptoms. Our systematic review was conducted according to the PRISMA guidelines and aimed to summarize the literature regarding the use of cannabinoids in ASD. After searching in Web of KnowledgeTM, PsycINFO, and Embase, we included ten studies (eight papers and two abstracts). Four ongoing trials were retrieved in ClinicalTrials.gov. Findings are promising, as cannabinoids appeared to improve problem behaviors, sleep, hyperactivity, and communication deficits, with limited cardiac and metabolic side effects. Interestingly, they generally allowed to reduce the number of prescribed medications and decreased the frequency of seizures in epileptic patients. Mechanisms of action could be linked to the excitatory/inhibitory imbalance found in people with ASD. However, further trials need to be implemented with better characterization and homogenization of samples, and well-defined outcomes.
REVIEW | doi:10.20944/preprints201912.0179.v1
Subject: Biology And Life Sciences, Biophysics Keywords: globular set; category theory; multidimensional; visual recognition; drug-resistant epilepsy; transcranial magnetic stimulation.
Online: 13 December 2019 (10:37:03 CET)
Once a wheat sheaf has been sealed and tied up, its packed down straws display the same orientation and zero-divergence. This observation brings us to the mathematical notion of presheaf, i.e., a topological structure in which diverging functions are locally superimposed. We show how the concepts of presheaves and the correlated globular sets, borrowed from category theory and algebraic topology, allow a well-founded mathematical approach to otherwise elusive activities of the brain. The mathematical assessment of brain functions in terms of presheaves: a) explains why spontaneous random spikes synchronize; b) leads to the counterintuitive intuition of antidromic effects in neuronal spikes: when an entrained oscillation propagates from A to B, changes in B lead to changes in A. We provide testable previsions: a) we suggest the proper locations of transcranial magnetic stimulation’s coils to improve the clinical outcomes of drug-resistant epilepsy; b) we advocate that axonal stimulation by external sources backpropagates and alters the neuronal electric oscillatory frequency. Further, we describe how the hierarchical information transmission inside globular sets provides fresh insights concerning different issues at various coarse-grained scales, such as object persistence, memory reinforcement in spite of random noise, Bayesian inferential circuits.
ARTICLE | doi:10.20944/preprints202306.1329.v1
Subject: Computer Science And Mathematics, Artificial Intelligence And Machine Learning Keywords: Epilepsy; seizure detection; EEG signals; LSTM; GRU; Convolutional Neural Networks; Deep Learning; Machine Learning
Online: 19 June 2023 (08:51:52 CEST)
Epilepsy is a chronic neurological disorder characterized by abnormal electrical activity in the brain, often leading to recurrent seizures. With approximately 50 million people worldwide affected by epilepsy, there is a pressing need for efficient and accurate methods to detect and diagnose seizures. Electroencephalogram (EEG) signals, which record the brain’s electrical activity, have emerged as a valuable tool in detecting epilepsy and other neurological disorders. Traditionally, the process of analyzing EEG signals for seizure detection has relied on manual inspection by experts, which is time-consuming, labor-intensive, and susceptible to human error. To address these limitations, researchers have turned to machine learning and deep learning techniques to automate the seizure detection process. In this work, we propose a novel method for epileptic seizure detection, leveraging the power of 1-D Convolutional layers in combination with Bidirectional Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) and Average pooling Layer as a unit. The performance of the proposed model is verified on the Bonn dataset. Our proposed model offers significant advancements over existing approaches for the detection of epileptic seizures, particularly for 2, 3, 4, and 5-class classification tasks. To assess the robustness and generalizability of our proposed architecture, we employ 5-fold cross-validation. By dividing the dataset into five subsets and iteratively training and testing the model on different combinations of these subsets, we obtain robust performance measures, including accuracy, sensitivity, and specificity. We demonstrate the effectiveness of the proposed architecture in accurately detecting epileptic seizures from EEG signals by using EEG signals of varying lengths. The results indicate its potential as a reliable and efficient tool for automated seizure detection, paving the way for improved diagnosis and management of epilepsy.
REVIEW | doi:10.20944/preprints202304.0224.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: endocannabinoid system; cognition; neurotransmitters; CB receptors; endocannabinoid catabolism; Alzheimer's disease; tempral lobe epilepsy; protection
Online: 11 April 2023 (10:56:55 CEST)
Cognitive functions are based on neuronal plasticity, which is provided by various mechanisms involving numerous bioactive molecules, the most important of which are endocannabinoids (eCBs). Over the past three decades, a lot of data have been accumulated on the involvement of eCBs in the mechanisms of memory and other cognitive functions. These functions are impaired in neurodegenerative diseases such as Alzheimer's disease (AD) and temporal lobe epilepsy (TLE). The main pathological feature of neurons in AD and TLE is increased excitability; therefore, an activation of the endocannabinoid system, which controls cellular excitation, may be a promising approach in their therapy. The available information about the effect of (endo)cannabinoids on cognitive functions is contradictory, which may depend on the drugs used, their dose, and the experimental conditions. There is an extensive literature indicating a protective effect of cannabinoids in the treatment of neurodegenerative diseases in humans and in animal models of cognitive deficits. This review, focusing on the recent researches, is devoted to the analysis of the effects of endocannabinoid system activation on cognitive functions in norm and in the brain with neurodegeneration that occurs in AD and TLE diseases. Possible reasons for inconsistencies in the available data are discussed.
ARTICLE | doi:10.20944/preprints202010.0616.v1
Subject: Computer Science And Mathematics, Algebra And Number Theory Keywords: Spike-and-wave; Generalized Gaussian distribution; EEG; Morlet wavelet; k-nearest neighbors classifier; Epilepsy
Online: 29 October 2020 (14:05:54 CET)
Spike-and-wave discharge (SWD) pattern detection in electroencephalography (EEG) signals is a key signal processing problem. It is particularly important for overcoming time-consuming, difficult, and error-prone manual analysis of long-term EEG recordings. This paper presents a new SWD method with a low computational complexity that can be easily trained with data from standard medical protocols. Precisely, EEG signals are divided into time segments for which the Morlet 1-D decomposition is applied. The generalized Gaussian distribution (GGD) statistical model is fitted to the resulting wavelet coefficients. A k-nearest neighbors (k-NN) self-supervised classifier is trained using the GGD parameters to detect the spike-and-wave pattern. Experiments were conducted using 106 spike-and-wave signals and 106 non-spike-and-wave signals for training and another 96 annotated EEG segments from six human subjects for testing. The proposed SWD classification methodology achieved 95 % sensitivity (True positive rate), 87% specificity (True Negative Rate), and 92% accuracy. These results set the path to new research to study causes underlying the so-called absence epilepsy in long-term EEG recordings.
ARTICLE | doi:10.20944/preprints202309.2036.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: Blood brain barrier, Gliosis, Temporal lobe epilepsy, Inflammation, Epileptogenesis, Hippocampus, Endothelial cells, Pericytes, Basal membrane
Online: 29 September 2023 (08:26:25 CEST)
Temporal lobe epilepsy (TLE) is associated with reorganization of neuronal networks, gliosis, neuroinflammation, loss of integrity of the blood brain barrier (BBB) in the hippocampus in humans and animal models. More than 30% of epilepsies remain intractable and characterization of the molecular mechanisms involved in BBB dysfunction is essential to the identification of new therapeutic strategies. In this work, we induced status epilepticus in rats by injection of the proconvulsant drug pilocarpine that leads to TLE. Using RT-qPCR, double immunohistochemistry and confocal imaging, we studied at different time points of epileptogenesis (latent phase, 3, 7, 14 days; chronic phase, 1 and 3 months) the regulation of reactive glia and vascular markers. In the hippocampus, increased expression of mRNA encoding the glial proteins GFAP and Iba1 confirmed neuroinflammatory status. We report for the first time the concomitant induction in endothelial cells, pericytes and basal membrane of the BBB of specific proteins CD31, PDGFR and ColIV, that peaks at the same time points as inflammation. The altered expression of these proteins occurs early in TLE, during the latent phase, suggesting that they could be associated with early rupture and pathogenicity of the BBB that will contribute to the chronic phase of epilepsy.
ARTICLE | doi:10.20944/preprints202309.1697.v1
Subject: Biology And Life Sciences, Neuroscience And Neurology Keywords: temporal lobe epilepsy; anakinra; lithium–pilocarpine model; behavior; epileptogenesis; hippocampus; spontaneous recurrent seizures; neuronal loss
Online: 26 September 2023 (05:16:16 CEST)
Temporal lobe epilepsy is a common, chronic disorder with spontaneous seizures that is often refractory to drug therapy. A potential cause of temporal lobe epilepsy is primary brain injury, making prevention of epileptogenesis after the initial event an optimal method of treatment. Despite this, no preventive therapy for epilepsy is currently available. The purpose of this study was to evaluate the effects of anakinra, lamotrigine, and their combination on epileptogenesis using the rat lithium-pilocarpine model of temporal lobe epilepsy. The study showed that the treated and untreated animals showed no significant difference in the number and duration of seizures. However, the severity of seizures was significantly reduced after treatment. Anakinra and lamotrigine, alone or in combination, significantly reduced neuronal loss in the CA1 hippocampus compared to the control group. However, the drugs administered alone were found to be more effective for CA3 than their combination. The treatment alleviated the impairments in activity level, exploratory behavior and anxiety, but had a relatively weak effect on TLE-induced impairments in social behavior and memory. The efficacy of the combination treatment did not differ from that of anakinra and lamotrigine monotherapy. These findings suggest that anakinra and lamotrigine, alone or in combination, may have clinical utility in preventing epileptogenesis.
ARTICLE | doi:10.20944/preprints202012.0527.v1
Subject: Computer Science And Mathematics, Algebra And Number Theory Keywords: epilepsy; seizure detection; electroencephalography; classification with a deferral option; home monitoring; long-term monitoring; wearables
Online: 21 December 2020 (13:40:43 CET)
Wearable technology will become available and allow prolonged electroencephalography (EEG) monitoring in the home environment of patients with epilepsy. Neurologists analyse the EEG visually and annotate all seizures, which patients often under report. Visual analysis of a 24 hour EEG recording typically takes one to two hours. Reliable automated seizure detection algorithms will be crucial to reduce this analysis. We study a dataset of behind-the-ear EEG measurements. Our first aim was to develop a methodology to reduce the EEG dataset by classifying part of the data automatically, while retaining 100% detection sensitivity (DS). Prediction confidences are determined by temperature scaling of the classification model outputs and trust scores. A DS of approximately 90% (99%) can be achieved when automatically classifying around 90% (60%) of the data. Perfect DS can be achieved when automatically classifying 50% of the data. Our second contribution demonstrates that a common modelling strategy, where predictions from several short EEG segments are used to obtain a final prediction, can be improved by filtering out untrustworthy segments with low trust scores. The false detection rate shows a relative decrease between 21% and 43%, and the DS shows a small increase or decrease.
ARTICLE | doi:10.20944/preprints201811.0493.v1
Subject: Social Sciences, Behavior Sciences Keywords: recognition of epilepsy EEG; Symlet wavelet; gradient boosting machine; grid search optimizer; multiple-index evaluation
Online: 20 November 2018 (09:31:20 CET)
Automatic recognition methods for non-stationary EEG data collected from EEG sensors play an essential role in neurological detection. The integrative approaches proposed in this study consists of Symlet wavelet processing, a gradient boosting machine, and a grid search optimizer for a three-level classification scheme for normal subjects, intermittent epilepsy, and continuous epilepsy. Fourth-order Symlet wavelets were adopted to decompose the EEG data into five time-frequency sub-bands, whose statistical features were computed and used as classification features. The grid search optimizer was used to automatically find the optimal parameters for training the classifier. The classification accuracy of the gradient boosting machine was compared with that of a support vector machine and a random forest classifier constructed according to previous descriptions. Multiple-index were used to evaluate the Symlet wavelet transform-gradient boosting machine-grid search optimizer classification scheme, which provided better classification accuracy and detection effectiveness than has recently reported in other work on three-level classification of EEG data.
ARTICLE | doi:10.20944/preprints202306.1815.v2
Subject: Social Sciences, Cognitive Science Keywords: neurofeedback; memory enhancement; medial temporal lobe; intracranial electrode; bidirectional control; memory encoding; intracranial electroencephalogram; intractable epilepsy
Online: 28 June 2023 (12:56:15 CEST)
Neurofeedback (NF) shows promise in enhancing memory, but its application to the medial temporal lobe (MTL) still needs to be studied. Therefore, we aimed to develop an NF system for the memory function of the MTL and examine neural activity changes, and memory task score changes through NF training. We created a memory NF system using intracranial electrodes to acquire and visualise the neural activity of the MTL during memory encoding. Twenty trials of a tug-of-war game per session were employed for NF and designed to control neural activity bidirectionally (Up/Down condition). NF training was conducted with three patients with intractable epilepsy, and we observed an increasing difference in NF signal between conditions (Up−Down) as NF training progressed. Similarities and negative correlation tendencies between the transition of neural activity and the transition of memory function were also observed. Our findings demonstrate NF's potential to modulate MTL activity and memory encoding. Future research needs further improvements to the NF system to validate its effects on memory functions. Nonetheless, this study represents a crucial step in understanding NF's application to memory and provides valuable insights for developing more efficient memory enhancement strategies.
CASE REPORT | doi:10.20944/preprints202107.0661.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: CLN2; epilepsy; Jammu and Kashmir; loss of ambulation; neuronal ceroid lipofuscinoses type 2; neuroregression; seizures; TPP1
Online: 29 July 2021 (14:01:16 CEST)
We report diagnosis of Neuronal Ceroid Lipofuscinosis Type 2 (CLN2), a rare, hereditary neurodegenerative disease of childhood, in a four and a half year old girl, the first child of non-consanguineous parents with no family history. Despite extensive efforts by the parents, her clinical condition remained undiagnosed and without management, until recently. Our published “Bottom-up Approach”, based on comprehensive and multidisciplinary clinical, pathological, radiographical and genetic evaluations, played key role in diagnosis of the disease. Detailed analyses involving Next Generation Sequencing confirmed a missense variation NC_00011.10:g.6616374C>T (NP_000382.3:p.Arg339Gln; rs765380155) in exon 8 of TPP1 gene. In silico analyses predicted it to be highly pathogenic. Further family screening (including her both unaffected parents and asymptomatic, one year old younger sister) of the identified variation through Sanger Sequencing, revealed a perfect autosomal recessive segregation in the family. This study is the first case report on classic CLN2 from Jammu and Kashmir-India. This study is also indicating the effectiveness of our “Bottom-up Approach” in understanding rare disorders in low resource regions and the importance of timely diagnosis. Like in the proband, had diagnosis been established a bit early, the family might have benefitted at least with reference to their second child through counselling programmes.
ARTICLE | doi:10.20944/preprints202306.2253.v1
Subject: Computer Science And Mathematics, Artificial Intelligence And Machine Learning Keywords: Epilepsy; Seizure Prediction; Preictal; Federated Learning (FL); Spiking Encoder; Graph Convolutional Neural Network (GCNN); Patient-specific Personalization
Online: 30 June 2023 (14:48:14 CEST)
Electroencephalography (EEG) signals are the primary source for discriminating the preictal from the interictal stage, enabling early warnings before the seizure onset. The epileptic seizure prediction models face significant challenges due to data scarcity, diversity, and privacy. This paper proposes a three-tier architecture for epileptic seizure prediction associated with the Federated Learning (FL) model that enhances the capability by utilizing the significant amount of seizure patterns from globally distributed patients with data privacy. The determination of the preictal state is influenced by global and local model-assisted decision-making by modeling the two-level edge layer. Integrating the Spiking Encoder (SE) with Graph Convolutional Neural Network (Spiking-GCNN) works as the local model trained using the bi-timescale approach. Each local model utilizes the aggregated seizure knowledge from the different medical centers through FL and determines the preictal probability in the coarse-grained personalization. The Adaptive Neuro-Fuzzy Inference System (ANFIS) is utilized in fine-grained personalization to recognize epileptic seizure patients by examining the outcomes of the FL model, heart rate variability features, and patient-specific clinical features. The proposed seizure prediction is evaluated using benchmark datasets by comparing them with the existing works to demonstrate the potential results.
ARTICLE | doi:10.20944/preprints202306.0784.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: antiepileptic drugs; age; autism spectrum disorder; epilepsy; ketogenic diet; mitochondrial dysfunction; modified Atkins diet; neurodevelopmental regression, seizures
Online: 12 June 2023 (07:23:54 CEST)
Despite the high prevalence of epilepsy in individuals with autism spectrum disorder (ASD) there is little information regarding whether seizure characteristics and treatment effectiveness change across age. Using an on-line survey, seizure characteristics, effectiveness of antiepileptic treatments, comorbidities and ASD diagnosis were collected from individuals with ASD and seizures. We previously reported overall general patterns of treatment effectiveness but did not examine the effect of seizure characteristics or age on antiepileptic treatment effectiveness. Such information would improve the personalized medicine approach to the treatment of seizures in ASD. Survey data from 570 individuals with ASD and clinical seizures were analyzed. Seizure severity (seizure/week) decreased with age of onset of seizures, plateauing in adolescence, with a greater reduction in generalized tonic clonic (GTC) seizures with age. Seizure severity was worse in those with genetic disorders, neurodevelopmental regression (NDR) and poor sleep maintenance. Carbamazepine and oxcarbazepine were reported to be more effective when seizures started in later childhood while surgery and the Atkin’s/Modified Atkin’s Diet (A/MAD) were reported to be more effective when seizures started early in life. A/MAD and the ketogenic diet were reported to be more effective in those with NDR. Interestingly, atypical Landau-Kleffner syndrome was associated with mitochondrial dysfunction and NDR, suggesting a novel syndrome. These interesting findings need to be verified in independent, prospectively collected cohorts, but none-the-less these data provide some insight into novel relationships that may assist in a better understanding of epilepsy in ASD and providing insight into personalizing epilepsy care in ASD.
CASE REPORT | doi:10.20944/preprints202105.0101.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: GLUT1 deficiency syndrome, modified Atkins diet, cognition, dystonia, dyskinesia, seizure, epilepsy, ketogenic diet, glucose transporter type 1.
Online: 6 May 2021 (15:12:17 CEST)
Glucose is the primary energy fuel used by the brain and is transported across the blood-brain barrier (BBB) by the glucose transporter type 1 and 2. A GLUT1 genetic defect is responsible for glucose transporter type 1 deficiency syndrome (GLUT1DS). Patients with GLUT1DS may present with pharmaco-resistant epilepsy, developmental delay, microcephaly, and/or abnormal movements, with tremendous phenotypic variability. Diagnosis is made by the presence of specific clinical features, hypoglycorrhachia and an SLC2A1 gene mutation. Treatment with a ketogenic diet therapy (KDT) is the standard of care as it results in production of ketone bodies which can readily cross the BBB and provide an alternate energy source to the brain in the absence of glucose. KDTs have been shown to reduce seizures and abnormal movements in children diagnosed with GLUT1DS. However, little is known about the impact of KDT on cognitive function, seizures and movement disorders in adults newly diagnosed with GLUT1DS and started on a KDT in adulthood, or the appropriate ketogenic diet therapy to administer. This case report demonstrates the potential benefits of using a modified Atkins diet (MAD), a less restrictive ketogenic diet therapy on cognition, seizure control and motor function in an adult with newly-diagnosed GLUT1SD.
ARTICLE | doi:10.20944/preprints202309.1017.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: ketogenic diet; intermittent fasting; neurological disorders; stroke; epilepsy; traumatic brain injury; headache; Alzheimerʹs disease; behavioral disease; cancer; obesity
Online: 14 September 2023 (13:40:01 CEST)
Non-pharmacologic options like the ketogenic diet (KD) and intermittent fasting (IF) are practical nutritional interventions with minor reported side effects like gastrointestinal symptoms, dyslipidemia, and hypomagnesemia for various medical ailments. In conjunction with IF, KD shows promise in weight loss, diabetes management, cardiovascular disorders, polycystic ovarian syndrome, cancer, and chronic neurological disorders. Based on prior research, we have examined the mechanism of action of KD and IF and their effect on neurological diseases, cancer, and obesity. We have also suggested evidence-based recommendations for the safer practice of KD and IF. Despite potential benefits, long-term adherence to KD poses challenges. Periodic KD implementation may thus benefit newly diagnosed overweight or obese patients with type 2 diabetes mellitus, aiding blood glucose and lipid management while promoting weight loss. KD is a high-fat and low-carbohydrate diet with a ratio of fat to carbohydrates and protein being 4:1 or 3:1, and thus, for peripheral tissues and the brain, fatty acids become the mandatory source of cellular energy. Ketone bodies have been used as the primary energy source during fasting. KD has been utilized as an effective treatment for refractory epilepsy since the 1920s. Evidence of the neuroprotective role of KD in diseases like epilepsy, stroke, traumatic brain injury, Alzheimer’s disease, and other neurological diseases has been noted. Since the 1960s, KD has become a popular method for obesity treatment. In addition, KD has been suggested as a potent anticancer therapy when used alone or as an adjuvant. KD may increase tumor cell sensitivity when combined with classic chemotherapy and radiotherapy. Thus, the probability that modifying the diet can help manage obesity, cancer, and chronic neurological disease without depending on pharmacological treatment and their serious side effects for a lifetime is promising and requires further investigation. KD holds promise as a potential adjunctive therapy in various neurological disorders, offering new avenues for treatment and neuroprotection. IF has shown potential in slowing the progression of neurodegenerative diseases such as Alzheimer's and Parkinson's by promoting antioxidant defense and suppressing inflammation. KD and IF show promise in cancer therapy by targeting altered cancer cell metabolism. Additionally, KD may enhance the effects of standard treatments like chemotherapy and radiotherapy. Some of the most robust reports of keto's possible benefits have come from glioblastoma, a very aggressive brain cancer. KD has also shown strong evidence for its effectiveness in weight loss, mainly attributed to its appetite-suppressing action in ketosis. However, long-term adherence to KD can be challenging, and periodic KDs may help manage blood glucose and lipid levels in overweight or obese patients with type 2 diabetes mellitus. Likewise, IF may be more effective than regular calorie restriction for achieving weight loss goals when combined with exercise programs. More prospective human studies are warranted to evaluate both KD and IF's potential therapeutic effectiveness and safety.
REVIEW | doi:10.20944/preprints202204.0189.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: astrocytes; reactive astrogliosis; TGF-β; traumatic brain injury; stroke; aging; Alzheimer’s disease; Parkinson’s disease; amyotrophic lateral sclerosis; multiple sclerosis; epilepsy
Online: 20 April 2022 (09:06:47 CEST)
Astrocytes are essential for normal brain development and functioning. They respond to brain injury and disease through a process referred to as reactive astrogliosis, where the reactivity is highly heterogenous and context dependent. Reactive astrocytes are active contributors to brain pathology and can exert beneficial, detrimental, or mixed effects following brain insults. Transforming growth factor-β (TGF-β) has been identified as one of the key factors regulating astrocyte reactivity. Genetic and pharmacological manipulation of TGF-β signaling pathway in animal models of CNS injury and disease alters pathological and functional outcomes. This review aims to provide recent understanding regarding astrocyte reactivity and TGF-β signaling in brain injury, aging, and neurodegeneration. Further, it explores how TGF-β signaling modulates astrocyte reactivity and function.
REVIEW | doi:10.20944/preprints202307.2136.v1
Subject: Public Health And Healthcare, Public Health And Health Services Keywords: Epilepsy; Pediatric Drug Development (PDD); Therapeutic Orphans; Extrapolation of efficacy from adults to children; Antiseizure Medications (ASMs); Pediatric Investigation Plan (PIP)
Online: 1 August 2023 (02:49:45 CEST)
Modern drugs have changed epilepsy, which affects people of all ages. But for young people with epilepsy, the framework of drug development has stalled. In the wake of the thalidomide catastrophe, the misconception emerged that for people <18y antiseizure medications (ASMs) need separate proof of efficacy and safety (E&S), overall called “pediatric drug development.” This has been corrected to some extent. Authorities accept that ASMs are effective in <18y as well, but they still require "extrapolation of efficacy," as if minors were another species. In our view, the real problem is less that relevant parts of pediatric clinical epilepsy research over the past decades were useless, but that this has hampered research on meaningful challenges. We do not need to show that ASMs work also before the 18th birthday. But we need to learn how to best use ASMs to prevent brain damage in young patients and optimize ASMs use considering a broader range of aspects
ARTICLE | doi:10.20944/preprints202310.1525.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: glial cell line-derived neurotrophic factor; brain derived neurotrophic factor; cortisol; tumor necrosis factor-α; lacrimal fluid; blood serum; focal epilepsy; major depressive disorder; hypothalamic-pituitary-adrenocortical axis
Online: 24 October 2023 (10:16:57 CEST)
Our previous studies showed that in patients with brain diseases neurotrophic factors in lacrimal fluid (LF) may change more prominently than in blood serum (BS). Since glial cell line-derived neurotrophic factor (GDNF) is involved in control of neuronal networks in epileptic brain, we aimed to assess GDNF levels in LF and BS as well as BDNF, hypothalamic-pituitary-adrenocortical and inflammation indices in BS of patients with focal epilepsy (PWFE), epilepsy and comorbid depression (PWFE+MDD) compared with major depressive disorder (PWMDD) and healthy controls (HC). GDNF levels in BS were similar in patients and HC and higher in PWFE taking valproates. GDNF levels in LF were significantly lower in all patient groups compared to controls, and independent of drugs used. LF and BS GDNF concentrations positively correlated in HC, but not patient groups. BDNF level was lower in BS of patients compared with HC and higher in PWFE+MDD taking valproates. Logistic regression models demonstrated that GDNF decrease in LF may be an important predictor of focal epilepsy. Probability of focal epilepsy can be evaluated using GDNF in LF and BDNF in BS; MDD - GDNF in LF, cortisol and TNF-α in BS; epilepsy with MDD - GDNF in LF, TNF-α and BDNF in BS.