Kynurenine and oxidative stress in children having learning disorder with and without attention deficit hyperactivity disorder: possible role and involvement.

BACKGROUND: The etiological and pathophysiological factors of learning disorder (LD) and attention deficit hyperactivity disorder (ADHD) are currently not well understood. These disorders disrupt some cognitive abilities. Identifying biomarkers for these disorders is a cornerstone to their proper management. Kynurenine (KYN) and oxidative stress markers have been reported to influence some cognitive abilities. Therefore, the aim was to measure the level of KYN and some oxidative stress indicators in children with LD with and without ADHD and to investigate their correlations with the abilities of children with LD. METHODS: The study included 154 participants who were divided into 3 groups: one for children who have LD (N = 69); another for children with LD and ADHD (N = 31); and a group for neurotypical (NT) children (N = 54). IQ testing, reading, writing, and other ability performance evaluation was performed for children with LD. Measuring plasma levels of KYN, malondialdehyde, glutathione peroxidase, and superoxide dismutase by enzyme-linked immunosorbent assay was performed for all participants. RESULTS: Some IQ measures and learning skills differed between the first two groups. The biochemical measures differed between children with LD (with and without ADHD) and NT children (p < 0.001). However, the biochemical measures did not show a significant statistical difference between the first two groups. KYN and glutathione peroxidase levels were correlated with one-minute writing and at-risk quotient, respectively (p = 0.03;0.04). KYN and malondialdehyde showed the highest sensitivity and specificity values. CONCLUSION: These biochemical measures could be involved or have a role in the abilities' performance of children with specific learning disorder.

Correlation between diffusion tensor imaging measures and the reading and cognitive performance of Arabic readers: dyslexic children perspective.

PURPOSE: To investigate the correlation between the diffusion tensor imaging (DTI) measures and the reading, spelling, writing, rapid naming, memory, and motor abilities in Arabic dyslexic children. This could verify the influence of possible white matter alterations on the abilities of those children. METHODS: Twenty native Arabic-speaking children with dyslexia (15 males and 5 females; 8.2 years ± 1) underwent DTI of the brain on 1.5 T scanner. Diffusion-weighted images were acquired in 32 noncollinear direction. Tractography of the arcuate fasciculus (AF) was performed. Region of interest (ROI)-based approach was also used. Regions encompass superior longitudinal fasciculus (SLF), anterior and superior corona radiata (CR), and posterior limb of internal capsule (PLIC) were analyzed. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were measured. The aptitudes of those children were evaluated by the dyslexia assessment test. These abilities were statistically correlated with the FA and ADC of the AF and other ROIs. RESULTS: The reduction of FA of right AF was related to worse overall reading and related abilities performance. The ADC of right SLF was negatively correlated with memory abilities. The ADC of right PLIC was positively correlated with writing performance. Other relations were also found. CONCLUSION: White matter microstructural DTI measurements in the right AF, right PLIC, SLF, and left anterior and superior CR are correlated to reading, spelling, writing, memory, and rapid naming abilities of the participants. The DTI measures could be promising regarding their use as a biomarker for follow-up in developmental dyslexia.

Childhood Apraxia of Speech: Exploring Gluten Sensitivity and Changes in Glutamate and Gamma-Aminobutyric Acid Plasma Levels.

BACKGROUND: Individuals with childhood apraxia of speech (CAS) were reported to have genetic variations related to gluten sensitivity and some neuroanatomic changes, which could be associated with alterations in neurotransmitters levels such as glutamate and gamma-aminobutyric acid (GABA). The aim was to measure the levels of antigliadin immunoglobulin A (IgA) antibody, glutamate, and GABA in the plasma of children with CAS compared with children with delayed language development (DLD) and neurotypical (NT) children. METHODS: The participants (N = 120) were in three groups: Group I for CAS (N = 30), Group II for DLD (N = 60), and Group III for NT (N = 30). The abilities of children in Groups I and II were evaluated. The plasma levels of antigliadin IgA, glutamate, and GABA were determined by enzyme-linked immunosorbent assay. RESULTS: The intelligence quotient and expressive language age in Group I were low compared with Group II (P = 0.001; 0.004). The levels of antigliadin IgA and glutamate in Group I were higher compared with the other two groups, whereas the level of GABA was lower (P < 0.0001). An imbalance between glutamate and GABA was found in Group I. In Group II, no measures differed from NTs except lower GABA levels (P = 0.0007). CONCLUSIONS: The elevated levels of antigliadin IgA antibody and glutamate demonstrated high sensitivity and specificity, differentiating children with CAS from children with DLD and NT children. The low levels of GABA contributed to the imbalance between the excitatory and inhibitory neurotransmitters' levels detected in children with CAS.

BDNF Val66Met Polymorphism: Suggested Genetic Involvement in Some Children with Learning Disorder.

Brain-derived neurotrophic factor (BDNF) plays an essential role in neuronal survival, especially in areas responsible for memory and learning. The BDNF Val66Met polymorphism has been described as a cognitive modifier in people with neuropsychiatric disorders. BDNF levels have been found to be low in children with learning disorder (LD). However, Val66Met polymorphism has not been studied before in such children. The aim was to investigate the presence of BDNF val66Met polymorphism in a group of children with specific LD and to verify its impact on their cognitive abilities. The participants in this cross-sectional study (N = 111) were divided into two groups: one for children with LD and the other for neurotypical (NT) ones. Children with LD (N = 72) were diagnosed according to the DSM-5 criteria. Their abilities were evaluated using Stanford-Binet Intelligence Scale, dyslexia assessment test, Illinois Test of Psycholinguistic Abilities, and phonological awareness test. Genotyping of BDNF Val66Met polymorphism was performed for all participants. The frequency of the Met allele was 26% among children with LD (6 children had homozygous, 26 had heterozygous genotype). The percentage of participants with deficits in reading, writing, and phonemic segmentation was higher in Met allele carriers when compared to non-Met allele carriers in LD group. The frequency of Met allele among NT children was 3.85% (0 homozygous, 3 children had heterozygous genotype) (p = 0.00001). The high frequency of Val66Met polymorphism among children with LD introduces the BDNF gene as a genetic modifier of learning performance in some children who manifest specific learning disorder (developmental dyslexia).

Investigating the influence of ubiquinone blood level on the abilities of children with specific learning disorder.

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.

Johnson-McMillin Microtia Syndrome: New Additional Family.

Microtia is a congenital anomaly that is found with different prevalence among various populations. The exact etiology of ear anomalies is still unknown. We describe a new additional family with this rare disorder; Johnson-McMillin syndrome (JMS) where mother, son, and distant grandmother have multiple features of JMS in the form of microtia, facial asymmetry, ear malformation, hearing defect, and hypotrichosis. Variable presentations in this family could be referred to phenotype variation supporting an autosomal dominant pattern of inheritance. We observed that the mother was very sad and suffered from feelings of guilt. We found that she had isolated herself from family and community out of fear of being stigmatized and hurt. We concluded that the occurrence of microtia is of public health importance, adhering to traditional marriage customs in Egypt increases women's risk of giving birth to a disabled child, yet the mothers are blamed and shamed for their children's birth defects by their husbands, families, and communities, while the fathers are not stigmatized.