Mutations of AKT3 are associated with a wide spectrum of developmental disorders including extreme megalencephaly

Mutations of genes within the phosphatidylinositol-3-kinase (PI3K)-AKT-MTOR pathway are well known causes of brain overgrowth (megalencephaly) as well as segmental cortical dysplasia (such as hemimegalencephaly, focal cortical dysplasia and polymicrogyria). Mutations of the AKT3 gene have been reported in a few individuals with brain malformations, to date. Therefore, our understanding regarding the clinical and molecular spectrum associated with mutations of this critical gene is limited, with no clear genotype–phenotype correlations. We sought to further delineate this spectrum, study levels of mosaicism and identify genotype–phenotype correlations of AKT3-related disorders. We performed targeted sequencing of AKT3 on individuals with these phenotypes by molecular inversion probes and/or Sanger sequencing to determine the type and level of mosaicism of mutations. We analysed all clinical and brain imaging data of mutation-positive individuals including neuropathological analysis in one instance. We performed ex vivo kinase assays on AKT3 engineered with the patient mutations and examined the phospholipid binding profile of pleckstrin homology domain localizing mutations. We identified 14 new individuals with AKT3 mutations with several phenotypes dependent on the type of mutation and level of mosaicism. Our comprehensive clinical characterization, and review of all previously published patients, broadly segregates individuals with AKT3 mutations into two groups: patients with highly asymmetric cortical dysplasia caused by the common p.E17K mutation, and patients with constitutional AKT3 mutations exhibiting more variable phenotypes including bilateral cortical malformations, polymicrogyria, periventricular nodular heterotopia and diffuse megalencephaly without cortical dysplasia. All mutations increased kinase activity, and pleckstrin homology domain mutants exhibited enhanced phospholipid binding. Overall, our study shows that activating mutations of the critical AKT3 gene are associated with a wide spectrum of brain involvement ranging from focal or segmental brain malformations (such as hemimegalencephaly and polymicrogyria) predominantly due to mosaic AKT3 mutations, to diffuse bilateral cortical malformations, megalencephaly and heterotopia due to constitutional AKT3 mutations. We also provide the first detailed neuropathological examination of a child with extreme megalencephaly due to a constitutional AKT3 mutation. This child has one of the largest documented paediatric brain sizes, to our knowledge. Finally, our data show that constitutional AKT3 mutations are associated with megalencephaly, with or without autism, similar to PTEN-related disorders. Recognition of this broad clinical and molecular spectrum of AKT3 mutations is important for providing early diagnosis and appropriate management of affected individuals, and will facilitate targeted design of future human clinical trials using PI3K-AKT pathway inhibitors

Therapy-resistant cluster headache in childhood: case report and literature review

The mean age of onset of cluster headache (CH) is in the late third decade. Only few cases of childhood-onset (<14 years) CH have been reported in the literature. We report the case of an 11-year-old boy who suffered from sudden attacks of shock-like, intense pain, localized in the right orbital region, with associated photophobia, phonophobia, conjunctival injection, lacrimation, nasal congestion, rhinorrhoea and psychomotor agitation. The episodes lasted 60–180 min, and the headache frequency was one to three per day. Physical and neurological examinations, magnetic resonance imaging and blood examinations were normal. The first bout lasted 8 months. Attacks were resistant to every symptomatic and partially to prophylactic treatment that has been tried. The second bout lasted approximately 2 months

ZC4H2 deletions can cause severe phenotype in female carriers

ZC4H2 is involved in human brain development, and, if mutated, can be responsible for a rare X-linked disorder, originally presented in literature as Wieacker-Wolff syndrome and Miles-Carpenter syndrome. In males, severe intellectual disability is associated with variable symptoms of central and peripheral nervous system involvement, such as spasticity, hyperreflexia, muscle weakness, and arthrogryposis. Female carriers are usually described as asymptomatic or only mildly affected. Here, we report on a girl carrying a de novo deletion of ZC4H2 detected by array-CGH analysis. She showed a complex neurodevelopmental disorder resembling the clinical picture commonly observed in male patients. X-inactivation was found to be random. Additionally, she had an unusual appearance of fingers and hand creases, and electromyography showed a peculiar pattern of both neurogenic and myopathic anomalies. The present patient confirms that female carriers can also be severely affected. Systematic clinical investigations of both males and females are needed to define the variety in nature and severity of phenotypes related to ZC4H2 variants

Paradigm shift in the treatment of tuberous sclerosis: Effectiveness of everolimus

Tuberous sclerosis complex (TSC) is an autosomal dominant disease characterised by abnormal cell proliferation and differentiation that affects multiple organs and can lead to the growth of hamartomas. Tuberous sclerosis complex is caused by the disinhibition of the protein mTOR (mammalian target of rapamycin). In the past, various therapeutic approaches, even if only symptomatic, have been attempted to improve the clinical effects of this disease. While all of these therapeutic strategies are useful and are still used and indicated, they are symptomatic therapies based on the individual symptoms of the disease and therefore not fully effective in modifying long-term outcomes. A new therapeutic approach is the introduction of allosteric inhibitors of mTORC1, which allow restoration of metabolic homeostasis in mutant cells, potentially eliminating most of the clinical manifestations associated with Tuberous sclerosis complex. Everolimus, a mammalian target of the rapamycin inhibitor, is able to reduce hamartomas, correcting the specific molecular defect that causes Tuberous sclerosis complex. In this review, we report the findings from the literature on the use of everolimus as an effective and safe drug in the treatment of TSC manifestations affecting various organs, from the central nervous system to the heart

Frost tolerance of 24 olive cultivars and subsequent vegetative re-sprouting as indication of recovery ability

The appearance of fruit malformation was investigated in the strawberry cultivar ‘Capri’ at different temperatures (23, 25 and 26°C) and relative humidity (70, 85 and 87%) in greenhouse cultivation using frigo (traditional, cold-stored) plants. In a second trial, the crop load was reduced by thinning different flower structures (at the crown apex, emerging inflorescences, and single flowers) in waiting bed plants (larger plants with well-differentiated flower buds). At fruit harvest, the percentage of misshapen fruits was recorded and the degree of the malformation was scored. In experiment 1, a higher incidence of fruit deformation was detected under higher temperature. In experiment 2, fruit malformation decreased by reducing the number of flowers per plant. In both experiments, tertiary and quaternary fruits showed a higher proportion of undeveloped fruit tips compared with primary and secondary fruits, but the degree of malformation was less. Anatomical modifications of fruit tissue were observed inside the undeveloped tips

Efficacy of Everolimus Low-Dose Treatment for Cardiac Rhabdomyomas in Neonatal Tuberous Sclerosis: Case Report and Literature Review

none10Background: Cardiac rhabdomyomas (CRs) are the most common cardiac tumors in newborns. Approximately 80-90% of cases are associated with tuberous sclerosis complex (TSC). In selective cases, Everolimus has resulted in a remarkable tumoral regression effect in children with TS. The optimal dosage for neonates is still unknown. Case presentation: We describe the use of Everolimus in a neonate with multiple biventricular CRs, causing subaortic obstruction, in which a low-dose treatment (0.1 mg/die), in an effort to maintain serum trough levels of 3-7 ng/mL, was successfully used off-label, without adverse effects. Conclusions: We showed that a low-dose Everolimus regimen may be an effective and safe treatment for CR regression in TS neonates, when the minimum therapeutic range was maintained.openNespoli, Luisa Federica; Albani, Elena; Corti, Carla; Spaccini, Luigina; Alfei, Enrico; Daniele, Irene; Zuccotti, Gian Vincenzo; Lista, Gianluca; Calcaterra, Valeria; Mannarino, SavinaNespoli, Luisa Federica; Albani, Elena; Corti, Carla; Spaccini, Luigina; Alfei, Enrico; Daniele, Irene; Zuccotti, Gian Vincenzo; Lista, Gianluca; Calcaterra, Valeria; Mannarino, Savin

The Diagnostic Yield of Array Comparative Genomic Hybridization Is High Regardless of Severity of Intellectual Disability/Developmental Delay in Children

Microarray-based comparative genomic hybridization is a method of molecular analysis that identifies chromosomal anomalies (or copy number variants) that correlate with clinical phenotypes. The aim of the present study was to apply a clinical score previously designated by de Vries to 329 patients with intellectual disability/developmental disorder (intellectual disability/developmental delay) referred to our tertiary center and to see whether the clinical factors are associated with a positive outcome of aCGH analyses. Another goal was to test the association between a positive microarray-based comparative genomic hybridization result and the severity of intellectual disability/developmental delay. Microarray-based comparative genomic hybridization identified structural chromosomal alterations responsible for the intellectual disability/developmental delay phenotype in 16% of our sample. Our study showed that causative copy number variants are frequently found even in cases of mild intellectual disability (30.77%). We want to emphasize the need to conduct microarray-based comparative genomic hybridization on all individuals with intellectual disability/developmental delay, regardless of the severity, because the degree of intellectual disability/developmental delay does not predict the diagnostic yield of microarray-based comparative genomic hybridization

CDKL5 deficiency disorder in males: Five new variants and review of the literature

The X-linked Cyclin-Dependent Kinase-Like 5 (CDKL5) gene encodes a serine-threonine kinase highly expressed in the developing brain. Loss of function of CDKL5 is pointed out to underlie the CDKL5 Deficiency Disorder (CDD), an X-linked dominant disease characterized by early-onset epileptic encephalopathy and developmental delay, usually affecting females more than males. To the best to our knowledge, only 45 males with CDD have been reported so far. Type and position of CDKL5 variants with different impact on the protein are reported to influence the clinical presentation. X-chromosome inactivation occurring in females and post-zygotic mosaicism in males are also believed to contribute to this variability. Based on these issues, genotype-phenotype correlations are still challenging. Here, we describe clinical features of five additional affected males with unreported CDKL5 variants, expanding the molecular spectrum of the disorder. We also reviewed the clinical profile of the previously reported 45 males with molecularly confirmed CDD. Severe developmental delay, cortical visual impairment, and early-onset refractory epilepsy characterize the CDD picture in males. By assessing the molecular spectrum, we confirm that germ-line truncating CDKL5 variants, equally distributed across the coding sequence, are the most recurrent mutations in CDD, and cause the worsen phenotype. While recurrence and relevance of missense substitutions within C-terminal remain still debated, disease-causing missense changes affecting the N-terminal catalytic domain correlate to a severe clinical phenotype. Finally, our data provide evidence that post-zygotic CDKL5 mosaicism may result in milder phenotypes and, at least in a subset of subjects, in variable response to antiepileptic treatments

Cognitive, Behavioral and Socioemotional Development in a Cohort of Preterm Infants at School Age: A Cross-Sectional Study

More than 50% of children who survive prematurity have an atypical course of development at school age, as environmental demands become more demanding. This study examines the effects of preterm birth on the cognitive, behavioral and socio emotional development of 185 children at ages five and seven years. Weaknesses were found in attention, working memory, processing speed and the ability to correctly interpret emotions at both ages five and seven. Significant correlations were found in regression and moderation models. These findings suggest that school-age children who were preterm infants are at increased risk of exhibiting impairments in several developmental domains that may affect their overall quality of life

Etiological research in pediatric multiple sclerosis: A tool to assess environmental exposures (PEQ-IT)

Not availabl