ATP-evoked intracellular Ca2+ transients shape the ionic permeability of human microglia from epileptic temporal cortex

BACKGROUND: Intracellular Ca2+ modulates several microglial activities, such as proliferation, migration, phagocytosis, and inflammatory mediator secretion. Extracellular ATP, the levels of which significantly change during epileptic seizures, activates specific receptors leading to an increase of intracellular free Ca2+ concentration ([Ca2+]i). Here, we aimed to functionally characterize human microglia obtained from cortices of subjects with temporal lobe epilepsy, focusing on the Ca2+-mediated response triggered by purinergic signaling.METHODS: Fura-2 based fluorescence microscopy was used to measure [Ca2+]i in primary cultures of human microglial cells obtained from surgical specimens. The perforated patch-clamp technique, which preserves the cytoplasmic milieu, was used to measure ATP-evoked Ca2+-dependent whole-cell currents.RESULTS: In human microglia extracellular ATP evoked [Ca2+]i increases depend on Ca2+ entry from the extracellular space and on Ca2+ mobilization from intracellular compartments. Extracellular ATP also induced a transient fivefold potentiation of the total transmembrane current, which was completely abolished when [Ca2+]i increases were prevented by removing external Ca2+ and using an intracellular Ca2+ chelator. TRAM-34, a selective KCa3.1 blocker, significantly reduced the ATP-induced current potentiation but did not abolish it. The removal of external Cl- in the presence of TRAM-34 further lowered the ATP-evoked effect. A direct comparison between the ATP-evoked mean current potentiation and mean Ca2+ transient amplitude revealed a linear correlation. Treatment of microglial cells with LPS for 48h did not prevent the ATP-induced Ca2+ mobilization but completely abolished the ATP-mediated current potentiation. The absence of the Ca2+-evoked K+ current led to a less sustained ATP-evoked Ca2+ entry, as shown by the faster Ca2+ transient kinetics observed in LPS-treated microglia.CONCLUSIONS: Our study confirms a functional role for KCa3.1 channels in human microglia, linking ATP-evoked Ca2+ transients to changes in membrane conductance, with an inflammation-dependent mechanism, and suggests that during brain inflammation the KCa3.1-mediated microglial response to purinergic signaling may be reduced

Prime nella vita comune - Impronte femminili nella specie umana

Le impronte femminili segnano tutti gli aspetti della vita di ciascuno, in ogni luogo e tempo, ma sono spesso celate, appannate dalla scontatezza del quotidiano e talvolta svilite dalle donne stesse. Obiettivo di quest’opera è farle emergere utilizzando differenti approcci: antropologico, sociologico, storico, filosofico. Si ripercorrono varie dimensioni dell’esistenza umana alla ricerca del contributo femminile, partendo dal positivo, ma senza rimuovere il negativo, le contraddizioni: dal rapporto con il proprio corpo a quello con la natura, dalla dimensione culturale a quella materiale, passando per la sfera sociale. A quest’ultima si è particolarmente dedicata la sottoscritta, facendo riferimento alle relazioni con gli altri e con le altre, con i più piccoli, tra i generi, in famiglia e in collettività più ampie

Long-term seizure outcome in frontal lobe epilepsy surgery

Purpose: The purpose of this study was to report long-term seizure outcome in patients who underwent frontal lobe epilepsy (FLE) surgery. Method: This retrospective study included 44 consecutive subjects who underwent resective surgery for intractable FLE at IRCCS NEUROMED (period 2001–2014), followed up for at least 2 years (mean: 8.7 years). All patients underwent noninvasive presurgical evaluation and/or invasive electroencephalography (EEG) monitoring when nonconcordant data were obtained or epileptogenic zone was hypothesized to be close to the eloquent cortex. Electroclinical, neuroimaging, surgical data, and histology were compared to seizure outcome. Results: Mean epilepsy duration was 19 years; mean age at surgery was 31.6 years. Preoperative magnetic resonance imaging (MRI) showed a frontal lesion in 86.4 % of cases. Scalp video-electroencephalography (VEEG) monitoring detected a focal ictal onset in 90% of cases. Twenty-seven patients (61.4%) underwent invasive recordings. Resections involved dorsolateral (47.7%), medial (9%), orbital (13.6%), and rolandic (13.6%) region. Lobectomy within functional boundaries was performed in the remaining 7 cases (16%). Transient and permanent neurological deficits were observed in 2 and 3 cases, respectively. Histology revealed focal cortical dysplasia (45.5%), World Health Organization (WHO) I–II grade tumors (15.9%), gliosis (22.7%), vascular malformations (4.5%), Rasmussen encephalitis (6.8%), and normal tissue (4.5%). At last observation 68.1% of patients were in Engel's class I, 11.4% in class II, 9% in class III, and 11.4% in class IV. A favorable outcome was associated with focal ictal scalp EEG onset (p = 0.0357). Conclusion: Surgery is a safe treatment option in drug-resistant FLE with a satisfying long-term outcome. These data highlight the importance of an appropriate selection of potential surgical candidates

Ictal Asystole in Drug-Resistant Focal Epilepsy: Two Decades of Experience from an Epilepsy Monitoring Unit

Background: Ictal asystole (IA) is a rare event observed in people with epilepsy (PwE). Clinical and IA video-electroencephalographic findings may be helpful in screening for high-risk subjects. Methods: From all PwE undergoing video-EEG for presurgical evaluation between 2000 and 2019, we retrospectively selected those with at least one IA (R–R interval of ≥3 s during a seizure). Results: IA was detected in eight out of 1088 (0.73%) subjects (mean age: 30 years; mean epilepsy duration: 9.6 years). Four out of them had a history of atonic falls. No patients had cardiac risk factors or cardiovascular diseases. Seizure onset was temporal (n = 5), temporo-parietal (n = 1) or frontal (n = 2), left-sided and right-sided in five and two patients, respectively. In one case a bilateral temporal independent seizure onset was recorded. IA was recorded in 11 out of 18 seizures. Mean IA duration was 13 s while mean IA latency from seizure onset was 26.7 s. Symptoms related to IA were observed in all seizures. Conclusion: IA is a rare and self-limiting event often observed during video-EG in patients with a history of atonic loss of consciousness and/or tardive falls in the course of a typical seizure

ATP-evoked intracellular Ca2+ transients shape the ionic permeability of human microglia from epileptic temporal cortex.

BackgroundIntracellular Ca2+ modulates several microglial activities, such as proliferation, migration, phagocytosis, and inflammatory mediator secretion. Extracellular ATP, the levels of which significantly change during epileptic seizures, activates specific receptors leading to an increase of intracellular free Ca2+ concentration ([Ca2+]i). Here, we aimed to functionally characterize human microglia obtained from cortices of subjects with temporal lobe epilepsy, focusing on the Ca2+-mediated response triggered by purinergic signaling.MethodsFura-2 based fluorescence microscopy was used to measure [Ca2+]i in primary cultures of human microglial cells obtained from surgical specimens. The perforated patch-clamp technique, which preserves the cytoplasmic milieu, was used to measure ATP-evoked Ca2+-dependent whole-cell currents.ResultsIn human microglia extracellular ATP evoked [Ca2+]i increases depend on Ca2+ entry from the extracellular space and on Ca2+ mobilization from intracellular compartments. Extracellular ATP also induced a transient fivefold potentiation of the total transmembrane current, which was completely abolished when [Ca2+]i increases were prevented by removing external Ca2+ and using an intracellular Ca2+ chelator. TRAM-34, a selective KCa3.1 blocker, significantly reduced the ATP-induced current potentiation but did not abolish it. The removal of external Cl- in the presence of TRAM-34 further lowered the ATP-evoked effect. A direct comparison between the ATP-evoked mean current potentiation and mean Ca2+ transient amplitude revealed a linear correlation. Treatment of microglial cells with LPS for 48 h did not prevent the ATP-induced Ca2+ mobilization but completely abolished the ATP-mediated current potentiation. The absence of the Ca2+-evoked K+ current led to a less sustained ATP-evoked Ca2+ entry, as shown by the faster Ca2+ transient kinetics observed in LPS-treated microglia.ConclusionsOur study confirms a functional role for KCa3.1 channels in human microglia, linking ATP-evoked Ca2+ transients to changes in membrane conductance, with an inflammation-dependent mechanism, and suggests that during brain inflammation the KCa3.1-mediated microglial response to purinergic signaling may be reduced

Temporal pole abnormalities in temporal lobe epilepsy with hippocampal sclerosis: Clinical significance and seizure outcome after surgery

PURPOSE: To assess the clinical significance of temporal pole abnormalities (temporopolar blurring, TB, and temporopolar atrophy, TA) in patients with temporal lobe epilepsy (TLE) and hippocampal sclerosis (HS) with a long post-surgical follow-up. METHODS: We studied 60 consecutive patients with TLE-HS and 1.5 preoperative MRI scans who underwent surgery and were followed up for at least 5 years (mean follow-up 7.3 years). Based on findings of pre-surgical MRI, patients were classified according to the presence of TB or TA. Groups were compared on demographic, clinical, neuropsychological data, and seizure outcome. RESULTS: TB was found in 37 (62%) patients, while TA was found in 35 (58%) patients, always ipsilateral to HS, with a high degree of overlap (83%) between TB and TA (p<0.001). Patients with TB did not differ from those without TB with regard to history of febrile convulsions, GTCSs, age of epilepsy onset, side of surgery, seizure frequency, seizure outcome, and neuropsychological outcome. On the other hand, they were significantly older, had a longer duration of epilepsy, and displayed lower preoperative scores on several neuropsychological tests. Similar findings were observed for TA. Multivariate analysis corroborated the association between temporopolar abnormalities and age at onset, age at surgery (for TB only), and lower preoperative scores on some neuropsychological tests. CONCLUSIONS: Temporopolar abnormalities are frequent in patients with TLE-HS. Our data support the hypothesis that TB and TA are caused by seizure-related damages. These abnormalities did not influence seizure outcome, even after a long-term post-surgical follow-up

Detection of Pneumocystis jirovecii and Aspergillus spp. DNa in bronchoalveolar lavage fluids by commercial real-time PCr assays: comparison with conventional diagnostic tests

The present study employed two commercial real-time PCR kits, MycAssay™ Pneumocystis (PJ-PCR) and MycAssay™ Aspergillus (ASP-PCR), for the search of fungal DNA on 44 bronchoalveolar lavage (BAL) fluids from patients at risk of invasive fungal disease. Operationally, on the basis of clinical diagnosis and according to the European Organization for Research and Treatment Cancer/Mycoses Study Group (EORTC/MSG) criteria, patients were clustered in 3 groups: a P. jirovecii pneumonia (PCP) group, an invasive aspergillosis (IA) group and a control (CTRL) group, consisting of 8, 10 and 24 patients, respectively. The results were compared to those obtained with conventional diagnostic assays, including BAL culture, galactomannan-ELISA (GM) and immunofluorescence (IF). The PJ-PCR assay returned a sensitivity and specificity of 100% and 94.4%, respectively. The ASP-PCR assay showed a sensitivity and specificity of 80% and 97.1%. When compared to the culture assay, the ASP-PCR showed enhanced sensitivity, and a good level of agreement (kappa = 0.63) was observed between ASP-PCR and GM assays. Overall, our data emphasize the diagnostic usefulness of the two commercial real-time PCR assays, especially in high-risk patients where timing is critical and a low fungal burden may hamper correct and prompt diagnosis by conventional tests

Temporal pole abnormalities detected by 3 T MRI in temporal lobe epilepsy due to hippocampal sclerosis: No influence on seizure outcome after surgery

PURPOSE: To assess the clinical significance of temporal pole abnormalities (temporopolar blurring, TB, and temporopolar atrophy, TA) detected by using 3 Tesla MRI in the preoperative workup in patients with temporal lobe epilepsy due to hippocampal sclerosis (TLE-HS) who underwent surgery. METHODS: We studied 78 consecutive patients with TLE-HS who underwent surgery and were followed up for at least 2 years. Based on findings of pre-surgical 3 Tesla MRI, patients were subdivided in subgroups according to the presence of TB or TA. Subgroups were compared on demographic, clinical, neuropsychological data and seizure outcome. RESULTS: TB was found in 39 (50%) patients, while TA was found in 32 (41%) patients, always ipsilateral to HS, with a considerable degree of overlap (69%) between TB and TA (p=0.01). Patients with temporopolar abnormalities did not significantly differ from those without TB or TA with regard to sex, age, age of epilepsy onset, duration of epilepsy, history of febrile convulsions or birth complications, side of surgery, seizure frequency at surgery, presence of GTCSs, and, in particular, seizure outcome. On the other hand, TB patients show a less frequent family history of epilepsy (p<.05) while age at epilepsy onset showed a trend to be lower in the TB group (p=.09). Patients with temporopolar atrophy did not significantly differ from those without TA on any variable, except for age at epilepsy onset, which was significantly lower for the TA group (p<.05). History of birth complications and longer duration of epilepsy also showed a trend to be associated with TA (p=.08). Multivariate analysis corroborated the association between temporopolar abnormalities and absence of family history of epilepsy and history of birth complications. CONCLUSIONS: High-field 3 T MRI in the preoperative workup for epilepsy surgery confirms that temporopolar abnormalities are frequent findings in TLE-HS patients and may be helpful to lateralize the epileptogenic zone. Their presence did not influence seizure outcome