Drosophila SPG12 ortholog, reticulon-like 1, governs presynaptic ER organization and Ca2+ dynamics.

Neuronal endoplasmic reticulum (ER) appears continuous throughout the cell. Its shape and continuity are influenced by ER-shaping proteins, mutations in which can cause distal axon degeneration in Hereditary Spastic Paraplegia (HSP). We therefore asked how loss of Rtnl1, a Drosophila ortholog of the human HSP gene RTN2 (SPG12), which encodes an ER-shaping protein, affects ER organization and the function of presynaptic terminals.

Endoplasmic Reticulum Lumenal Indicators in Reveal Effects of HSP-Related Mutations on Endoplasmic Reticulum Calcium Dynamics.

Genes for endoplasmic reticulum (ER)-shaping proteins are among the most commonly mutated in hereditary spastic paraplegia (HSP). Mutation of these genes in model organisms can lead to disruption of the ER network. To investigate how the physiological roles of the ER might be affected by such disruption, we developed tools to interrogate its Ca signaling function.

Rapid Release of Ca from Endoplasmic Reticulum Mediated by Na/Ca Exchange.

Phototransduction in is mediated by phospholipase C (PLC) and Ca-permeable TRP channels, but the function of endoplasmic reticulum (ER) Ca stores in this important model for Ca signaling remains obscure. We therefore expressed a low affinity Ca indicator (ER-GCaMP6-150) in the ER, and measured its fluorescence both in dissociated ommatidia and from intact flies of both sexes. Blue excitation light induced a rapid (tau ∼0.

Dynamic action potential clamp predicts functional separation in mild familial and severe de novo forms of epilepsy.

De novo variants in developmental and epileptic encephalopathy (DEE) show distinctive genotype-phenotype correlations. The two most recurrent variants in DEE, R1882Q and R853Q, are associated with different ages and seizure types at onset. R1882Q presents on day 1 of life with focal seizures, while infantile spasms is the dominant seizure type seen in R853Q cases, presenting at a median age of 8 months.

Sodium channels and the neurobiology of epilepsy.

Voltage-gated sodium channels (VGSCs) are integral membrane proteins. They are essential for normal neurologic function and are, currently, the most common recognized cause of genetic epilepsy. This review summarizes the neurobiology of VGSCs, their association with different epilepsy syndromes, and the ways in which we can experimentally interrogate their function.

EEG dipole source localization of interictal spikes in non-lesional TLE with and without hippocampal sclerosis.

Purpose: A subgroup of patients with non-lesional temporal lobe epilepsy (NLTLE) have no evidence of hippocampal sclerosis (HS) on MRI or on histopathology. It is controversial whether this represents a different clinicopathological syndrome from NLTLE with HS, or whether both subgroups represent different ends of the spectrum of mesial TLE. Here the EEG source localization dipoles were compared between NLTLE patients with HS (HS+) and without HS (HS-), and the relationship with post-surgical outcome was investigated.

Comparison of radiofrequency exposure of a mouse dam and foetuses at 900 MHz.

In vivo studies involving radiofrequency (RF) exposure of rodents require detailed dosimetric analysis to enable correct interpretation of biological outcomes. Detailed anatomical models of mice--a female, a pregnant female, a male and a foetus--have been developed for analyses using finite difference numerical techniques. The mouse models, consisting of 49 tissues, will be made freely available to the research community.

The diagnostic value of oral lacerations and incontinence during convulsive "seizures".

Purpose: Oral lacerations and urinary incontinence have long been considered useful clinical features for the diagnosis of epileptic seizures; however, both are also reported in patients with psychogenic nonepileptic seizures (PNES). The aims of the study were (1) to investigate whether the presence and nature of oral lacerations or incontinence during convulsive seizures of patients with epilepsy differed from those with PNES, and (2) whether the side of the oral laceration has any correlation with the epilepsy syndrome or lateralization.

Methods: Eighty-four consecutive patients who experienced at least one convulsive event during video-EEG monitoring (VEM) were questioned and examined for oral lacerations and incontinence.