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Background Ubiquinone has antioxidant properties and has been linked to cognitive performance in some neuropsychiatric disorders. Its role in specific learning disorder manifestations has not been previously investigated. Therefore, the aim of this study was to measure the blood levels of ubiquinone in a group of children with specific learning disorder in comparison to typically developing children and to investigate the correlation between ubiquinone levels in children with specific learning disorder and some of their intellectual capabilities, reading, spelling and writing performance. Methods The study included 71 native Arabic speaking children: 31 in the specific learning disorder group and 40 in the typically developing (TD) group. The abilities of the children with specific learning disorder were evaluated by the Stanford-Binet Intelligence Scale-4th edition, the Dyslexia Assessment Test, and the Illinois Test of Psycholinguistic Abilities. The level of ubiquinone was measured in both groups by ELISA. Correlation between some aptitudes of children with specific learning disorder and the ubiquinone level was performed. Results The blood levels of ubiquinone in the children with specific learning disorder group were less than those in the TD group. Correlation analysis revealed a significant positive correlation between ubiquinone and the scores of backward digit span abilities. Conclusions Ubiquinone has a role in the auditory working memory performance of children with specific learning disorder (with impairment in reading). The decreased levels of ubiquinone in this sample of children with specific learning disorder could have participated in the pathogenesis of this disorder.

BackgroundDown syndrome (DS) is one of the commonest causes of developmental delay in children, with equilibrium problems being an integral part of the syndrome. This leads to further impairment of cognitive and concentration abilities.Material and MethodsIn our study, 30 DS children were categorized into 3 groups: bilateral normal middle ear pressure, bilateral abnormal middle ear pressure, and unilateral abnormal middle ear pressure. Sensory components of balance (somatosensory, visual, and vestibular) were assessed using computerized dynamic posturographyResultsResults showed a statistically significant decrease in composite score, visual ratio, and vestibular ratio among DS children compared to normal children. No significant differences in sensory parameters between the various DS groups (with various tympanogram types) were encountered.ConclusionsThis might lead one to suspect central and proprioceptive causes behind balance problems in DS, but further extended studies are needed to confirm this. Bedside screening tests for visual and vestibular functioning of balance are recommended, e.g. past pointing and Fukuda for early detection and intervention.

White matter lesions (WML) or leukoaraiosis is a major feature in cerebral imaging of older people, and their prevalence increases with age. The clinical effects of WML vary with the main impairment being detected in the cognitive functions, increased risk of severe depression and motor impairment. Although vascular comorbidities have been found to be the main changes in these brains, increased production of reactive oxygen species (ROS) could represent a risk factor for these lesions with elemental iron being a potential factor for ROS production. This study focuses on changes in iron, iron-regulating proteins and RNA expression of iron metabolism genes. Three groups of samples were used: WML, normal areas from lesional WM [NAWM (L)] as disease control and normal WM from control brains [NAWM(C)]. Ferric iron staining was undertaken using known Perl's reaction. Immunohistochemistry (IHC) of white matter for ceruloplasmin (Cp), haemochromatosis (HFE) and transferrin receptor (TfR) was done. Cellular localization of HFE and Cp was performed using dual-antibody IHC. Whole-genome RNA was extracted from WML, NAWM (L) and NAWM(C), and QPCR for HFE, TF, TfR, ceruloplasmin, ferritin and ferroportin was performed. Ferric iron staining shows increased diffuse iron staining among WML, followed by NAWM (L) and the least group being NAWM(C). IHC shows increased HFE and CP expression in lesional WM, while TfR shows no changes among the groups. HFE colocalized with vascular endothelium and microglia in WML and control samples, while Cp colocalized with microglia and some expression was shown by astrocytes. The mRNA expression using QPCR suggests a pattern that favours decreased intracellular iron influx, increased ferrous oxidation and increased iron export from the cells. Iron metabolism seems to be changed in brains with WML, increased elemental iron in these brains and in turn increased production of free oxidative radicals could represent a potentiating factor for the development of ageing WML.

Incidental white matter lesions (WML) are a common neuroradiological finding in elderly people and have been linked to dementia and depression. Various mechanisms including hypoxia and increased production of reactive oxygen species (ROS) are implicated in the etiology of WML. The hemochromatosis (HFE) gene p.H63D and p.C282Y polymorphisms have been linked to dysregulation of iron metabolism and increased levels of ROS, whereas Angiotensin II receptor 1 (AGTR1) c.1166A → C polymorphism is known as a vascular risk factor. These genetic polymorphisms were characterized in brains donated to the UK MRC Cognitive Function and Ageing Study (CFAS) to assess their potential role in the risk for development of age-related WML. The study cohort comprised 258 brain donated to CFAS. WML severity was assessed in the postmortem brain donations using magnetic resonance imaging (MRI) scans and scored using the Scheltens' scale. Polymerase chain reaction (PCR) amplification of extracted DNA followed by restriction enzyme digestion was used to genotype the samples. Genotypes were validated using direct sequencing in a smaller sample. The results show that HFE p.H63D polymorphism is not associated with WML severity in the whole cohort. However, there is a significant association of the D allele with severity of WML in noncarriers of the APOE ε4 allele. No association is demonstrated between the HFE p.C282Y nor the AGTR1 c.1166A → C polymorphisms and WML severity. The HFE gene appears to be a genetic risk factor for severe aging WML independently of the APOE ε4 genotype. This would support the role of iron-related oxidative stress, in addition to previously studied factors, e.g., hypoxia as potential risk factors for developing prominent aging WML.

Background Learning disorder (LD) is manifested by significant difficulties in the acquisition and use of reasoning, reading, writing, or mathematical abilities, despite average intelligence and proper education. Its etiological factors were suggested to be related to neurodevelopmental alterations. Measurement of the levels of brain-derived neurotrophic factor (BDNF) and coenzyme Q10 (CoQ10) was targeted in children with LD in comparison with typically developing (TD) ones. Materials and methods This study included 82 Egyptian Arabic-speaking children matched for age and sex and socioeconomic status, comprising 42 with specific LD (group I) and 40 TD children (group II). All participants were subjected to clinical and full neurological examination after reporting a full medical history. Furthermore, LD group was subjected to Stanford–Binet intelligence scale, dyslexia assessment test, and phonological awareness test, which evaluates cognitive and learning aptitudes. The levels of BDNF and CoQ10 were determined in serum by enzyme-linked immunosorbent assay. Results All children with LD obtained a score of 1 or more as at-risk quotient by the dyslexia assessment test, which indicated a specific reading disorder. The BDNF and CoQ10 levels in the LD group were significantly less than those in the TD group. No correlations were found between the measured markers and each other or between them and the measured factors of the used tests. Conclusion The detected low levels of BDNF and CoQ10 in children with specific LD with impairment in reading would be suspected to be related to etiological or exaggerating factors for the deficits in such children.