22 research outputs found

    Phenotypic and genetic spectrum of epilepsy with myoclonic atonic seizures

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    Objective: We aimed to describe the extent of neurodevelopmental impairments andidentify the genetic etiologies in a large cohort of patients with epilepsy with myoclonicatonic seizures (MAE).Methods: We deeply phenotyped MAE patients for epilepsy features, intellectualdisability, autism spectrum disorder, and attention-deficit/hyperactivity disorderusing standardized neuropsychological instruments. We performed exome analysis(whole exome sequencing) filtered on epilepsy and neuropsychiatric gene sets toidentify genetic etiologies.Results: We analyzed 101 patients with MAE (70% male). The median age of seizureonset was 34 months (range = 6-72 months). The main seizure types were myoclonicatonic or atonic in 100%, generalized tonic-clonic in 72%, myoclonic in 69%, absencein 60%, and tonic seizures in 19% of patients. We observed intellectual disability in62% of patients, with extremely low adaptive behavioral scores in 69%. In addition,24% exhibited symptoms of autism and 37% exhibited attention-deficit/hyperactivitysymptoms. We discovered pathogenic variants in 12 (14%) of 85 patients, includingfive previously published patients. These were pathogenic genetic variants inSYNGAP1 (n = 3), KIAA2022 (n = 2), and SLC6A1 (n = 2), as well as KCNA2,SCN2A, STX1B, KCNB1, and MECP2 (n = 1 each). We also identified three newcandidate genes, ASH1L, CHD4, and SMARCA2 in one patient each.Significance: MAE is associated with significant neurodevelopmental impairment.MAE is genetically heterogeneous, and we identified a pathogenic genetic etiologyin 14% of this cohort by exome analysis. These findings suggest that MAE is a manifestationof several etiologies rather than a discrete syndromic entity

    De novo DHDDS variants cause a neurodevelopmental and neurodegenerative disorder with myoclonus

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    Subcellular membrane systems are highly enriched in dolichol, whose role in organelle homeostasis and endosomal-lysosomal pathway remains largely unclear besides being involved in protein glycosylation. DHDDS encodes for the catalytic subunit (DHDDS) of the enzyme cis-prenyltransferase (cis-PTase), involved in dolichol biosynthesis and dolichol-dependent protein glycosylation in the endoplasmic reticulum. An autosomal recessive form of retinitis pigmentosa (retinitis pigmentosa 59) has been associated with a recurrent DHDDS variant. Moreover, two recurring de novo substitutions were detected in a few cases presenting with neurodevelopmental disorder, epilepsy, and movement disorder. We evaluated a large cohort of patients (n=25) with de novo pathogenic variants in DHDDS and provided the first systematic description of the clinical features and long-term outcome of this new neurodevelopmental and neurodegenerative disorder. The functional impact of the identified variants was explored by yeast complementation system and enzymatic assay. Patients presented during infancy or childhood with a variable association of neurodevelopmental disorder, generalized epilepsy, action myoclonus/cortical tremor, and ataxia. Later in the disease course they experienced a slow neurological decline with the emergence of hyperkinetic and/or hypokinetic movement disorder, cognitive deterioration, and psychiatric disturbances. Storage of lipidic material and altered lysosomes were detected in myelinated fibers and fibroblasts, suggesting a dysfunction of the lysosomal enzymatic scavenger machinery. Serum glycoprotein hypoglycosylation was not detected and, in contrast to retinitis pigmentosa and other congenital disorders of glycosylation involving dolichol metabolism, the urinary dolichol D18/D19 ratio was normal. Mapping the disease-causing variants into the protein structure revealed that most of them clustered around the active site of the DHDDS subunit. Functional studies using yeast complementation assay and in vitro activity measurements confirmed that these changes affected the catalytic activity of the cis-PTase and showed growth defect in yeast complementation system as compared with the wild-type enzyme and retinitis pigmentosa-associated protein. In conclusion, we characterized a distinctive neurodegenerative disorder due to de novo DHDDS variants, which clinically belongs to the spectrum of genetic progressive encephalopathies with myoclonus. Clinical and biochemical data from this cohort depicted a condition at the intersection of congenital disorders of glycosylation and inherited storage diseases with several features akin to of progressive myoclonus epilepsy such as neuronal ceroid lipofuscinosis and other lysosomal disorders

    Molecular Mechanisms Generating and Stabilizing Terminal 22q13 Deletions in 44 Subjects with Phelan/McDermid Syndrome

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    In this study, we used deletions at 22q13, which represent a substantial source of human pathology (Phelan/McDermid syndrome), as a model for investigating the molecular mechanisms of terminal deletions that are currently poorly understood. We characterized at the molecular level the genomic rearrangement in 44 unrelated patients with 22q13 monosomy resulting from simple terminal deletions (72%), ring chromosomes (14%), and unbalanced translocations (7%). We also discovered interstitial deletions between 17–74 kb in 9% of the patients. Haploinsufficiency of the SHANK3 gene, confirmed in all rearrangements, is very likely the cause of the major neurological features associated with PMS. SHANK3 mutations can also result in language and/or social interaction disabilities. We determined the breakpoint junctions in 29 cases, providing a realistic snapshot of the variety of mechanisms driving non-recurrent deletion and repair at chromosome ends. De novo telomere synthesis and telomere capture are used to repair terminal deletions; non-homologous end-joining or microhomology-mediated break-induced replication is probably involved in ring 22 formation and translocations; non-homologous end-joining and fork stalling and template switching prevail in cases with interstitial 22q13.3. For the first time, we also demonstrated that distinct stabilizing events of the same terminal deletion can occur in different early embryonic cells, proving that terminal deletions can be repaired by multistep healing events and supporting the recent hypothesis that rare pathogenic germline rearrangements may have mitotic origin. Finally, the progressive clinical deterioration observed throughout the longitudinal medical history of three subjects over forty years supports the hypothesis of a role for SHANK3 haploinsufficiency in neurological deterioration, in addition to its involvement in the neurobehavioral phenotype of PMS

    The James Webb Space Telescope Mission

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    Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4m4m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5m6.5m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

    Alterations in the α2 Ύ ligand, thrombospondin-1, in a rat model of spontaneous absence epilepsy and in patients with idiopathic/genetic generalized epilepsies

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    Objectives Thrombospondins, which are known to interact with the α2Ύ subunit of voltage-sensitive calcium channels to stimulate the formation of excitatory synapses, have recently been implicated in the process of epileptogenesis. No studies have been so far performed on thrombospondins in models of absence epilepsy. We examined whether expression of the gene encoding for thrombospondin-1 was altered in the brain of WAG/Rij rats, which model absence epilepsy in humans. In addition, we examined the frequency of genetic variants of THBS1 in a large cohort of children affected by idiopathic/genetic generalized epilepsies (IGE/GGEs). Methods We measured the transcripts of thrombospondin-1 and α2Ύ subunit, and protein levels of α2Ύ, Rab3A, and the vesicular glutamate transporter, VGLUT1, in the somatosensory cortex and ventrobasal thalamus of presymptomatic and symptomatic WAG/Rij rats and in two control strains by real-time polymerase chain reaction (PCR) and immunoblotting. We examined the genetic variants of THBS1 and CACNA2D1 in two independent cohorts of patients affected by IGE/GGE recruited through the Genetic Commission of the Italian League Against Epilepsy (LICE) and the EuroEPINOMICS-CoGIE Consortium. Results Thrombospondin-1 messenger RNA (mRNA) levels were largely reduced in the ventrobasal thalamus of both presymptomatic and symptomatic WAG/Rij rats, whereas levels in the somatosensory cortex were unchanged. VGLUT1 protein levels were also reduced in the ventrobasal thalamus of WAG/Rij rats. Genetic variants of THBS1 were significantly more frequent in patients affected by IGE/GGE than in nonepileptic controls, whereas the frequency of CACNA2D1 was unchanged. Significance These findings suggest that thrombospondin-1 may have a role in the pathogenesis of IGE/GGEs

    Sleep in children with attention-deficit/hyperactivity disorder (ADHD) before and after 6-month treatment with methylphenidate: a pilot study

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    Children with ADHD may present with sleep disturbances that add to the impairment of the disorder. The long-term sleep effects of the first-line pharmacological treatment for ADHD, i.e., psychostimulants, are unclear. In this pilot study, we compared polysomnographic variables in children with ADHD (n?=?11, aged 6–15 years), before pharmacological treatment, and in children without ADHD (n?=?22, aged 5–14 years); we also assessed polysomnographic changes in children with ADHD (n?=?7) after a 6-month treatment with methylphenidate immediate-release (once or twice daily). Compared to children without ADHD, those with ADHD at baseline presented with significantly increased duration of awakenings (p?=?0.02), reduction in sleep efficiency (p?=?0.03), and increase in stage I (N1) (p?<?0.01) and reduction in stage II (N2) (p?=?0.02) and stage III–IV (N3) percentages. Methylphenidate treatment did not significantly change any parameter of sleep architecture.Conclusion: Preliminary evidence from this pilot study shows that, compared to children without ADHD, those with ADHD presented a more fragmented and less effective sleep at baseline and that the 6-month methylphenidate treatment did not further negatively impact on sleep architecture

    Biologics in Severe Eosinophilic Asthma: Three-Year Follow-Up in a SANI Single Center

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    Introduction: Biologic drugs have dramatically improved severe eosinophilic asthma (SEA) outcomes. Our aim was to evaluate the long-term efficacy of biological therapy in SEA in a real-life setting and to identify the predictors for switching to another biological drug in patients with poor asthma control. The outcomes for efficacy were decreased annual exacerbations (AE) and improved asthma control test (ACT). Methods: In 90 SEA patients being treated with a biological drug, clinical examination, ACT, blood eosinophils count and spirometry were assessed before (T0) and after 6 (T1), 12 (T2), 24 (T3) and 36 (T4) months from the start of biological therapy. Patients were considered responders (R) or non-responders (NR) to biologics depending on whether or not they had less than two AE and a 20% increase in the ACT after 12 months of treatment. Results: 75% of the patients were R, 25% NR. In R patients, biological therapy add-on was followed by significant improvement in AE and ACT throughout the whole follow-up period. The percentage of patients on oral corticosteroids (OCS) dropped from 40% to 12%. By contrast, the NR patients were shifted to another biological drug after 12 months of therapy, as they still had high AE and nearly unchanged ACT; 40% of them still needed OCS treatment. The predictors of switching to another biological drug were three or more AE, ACT below 17, nasal polyposis and former smoking (p < 0.05). In NR, the shift to another biological drug was followed by a significant decrease in AE and an increase in the ACT. Discussion: This real-life study confirms the long-term efficacy of biologics in most SEA patients and indicates that even in non-responders to a first biological drug, it is worth trying a second one. It is hoped that the availability of additional biologics with different targets will help improve the personalization of SEA therapy

    Electroclinical Features of Epilepsy in Kleefstra Syndrome

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    Background Kleefstra's syndrome (KS) or 9q34.3 microdeletion syndrome (OMIM #610253) is a rare genetic condition featuring intellectual disability, hypotonia, and dysmorphic facial features. Autism spectrum disorder, severe language impairment, and sleep disorders have also been described. The syndrome can be either caused by a microdeletion in 9q34.3 or by pathogenic variants in the euchromatin histone methyltransferase 1 gene ( EHMT1 , *607001). Although epilepsy has been reported in 20 to 30% of subjects, a detailed description of epileptic features and underlying etiology is still lacking. The purpose of this study is to investigate epilepsy features in a cohort of epileptic patients with KS.Methods This multicenter study investigated eight patients with KS and epilepsy. Our findings were compared with literature data.Results We included five patients with 9q or 9q34.33 deletions, a subject with a complex translocation involving EHMT1 , and two with pathogenic EHMT1 variants. All patients presented with moderate to severe developmental delay, language impairment, microcephaly, and infantile hypotonia. Although the epileptic manifestations were heterogeneous, most patients experienced focal seizures. The seizure frequency differs according to the age of epilepsy onset, with patients with early-onset epilepsy (before 36 months of age) presenting more frequent seizures. An overtime reduction in seizure frequency, as well as in antiseizure drug number, was observed in all patients. Developmental delay degree did not correlate with seizure onset and frequency or drug resistance.Conclusion Epilepsy is a frequent finding in KS, but the underlying pathogenetic mechanism and specific features remain elusive

    COPD, but Not Asthma, Is Associated with Worse Outcomes in COVID-19: Real-Life Data from Four Main Centers in Northwest Italy

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    Introduction: Asthma, along with inhaled steroids, was initially considered a risk factor for worse clinical outcomes in COVID-19. This was related to the higher morbidity observed in asthma patients during previous viral outbreaks. This retrospective study aimed at evaluating the prevalence of asthma among patients admitted due to SARS-CoV-2 infection as well as the impact of inhaled therapies on their outcomes. Furthermore, a comparison between patients with asthma, COPD and the general population was made. Methods: All COVID-19 inpatients were recruited between February and July 2020 from four large hospitals in Northwest Italy. Data concerning medical history, the Charlson Comorbidity Index (CCI) and the hospital stay, including length, drugs and COVID-19 complications (respiratory failure, lung involvement, and the need for respiratory support) were collected, as well as the type of discharge. Results: patients with asthma required high-flow oxygen therapy (33.3 vs. 14.3%, p = 0.001) and invasive mechanical ventilation (17.9 vs. 9.5%, p = 0.048) more frequently when compared to the general population, but no other difference was observed. Moreover, asthma patients were generally younger than patients with COPD (59.2 vs. 76.8 years, p < 0.001), they showed both a lower mortality rate (15.4 vs. 39.4%, p < 0.001) and a lower CCI (3.4 vs. 6.2, p < 0.001). Patients with asthma in regular therapy with ICS at home had significantly shorter hospital stay compared to those with no treatments (25.2 vs. 11.3 days, p = 0.024). Discussion: Our study showed that asthma is not associated with worse outcomes of COVID-19, despite the higher need for respiratory support compared with the general population, while the use of ICS allowed for a shorter hospital stay. In addition, the comparison of asthma with COPD patients confirmed the greater frailty of the latter, according to their multiple comorbidities
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