Is afternoon cortisol more reliable than waking cortisol in association studies of children with an ASD?

Effects of physical exercise, LEGO, and Minecraft activities on anxiety in underserved children with autism: Study design and methodological strategies

Anxiety is a common comorbidity for individuals with ASD, and there is some preliminary data about the efficacy of physical exercise to alleviate anxiety. However, we are not aware of any studies that have compared the effects of a physical exercise program on anxiety in underserved children with ASD using a randomized controlled research design. This paper describes a method to evaluate and compare the efficacy of an 8-week physical exercise intervention with a sedentary play intervention to alleviate anxiety in young children with autism spectrum disorders (ASD) from underserved backgrounds. We assessed anxiety and its physical symptoms using the parent-rated Child Behavior Checklist DSM-5 anxiety (CBCL DSM-5) subscale, the child-rated Screen for Childhood Anxiety Related Emotional Disorder (SCARED), the parent-rated Child's Sleep Habits Questionnaire (CSHQ), and salivary cortisol. We also utilized the Physical Activity Questionnaire for Older Children (PAQ-C) to assess physical activity level and identify compounds. Unique components of this study include: •Implementation of novel physical exercise and sedentary play interventions that have been designed for children with ASD.•Recruitment of predominantly underserved and non-English speaking families.

IQ, parent- and self-reports of child anxiety and salivary cortisol in a sample of children with autism spectrum disorder

This study examined the relation between IQ, parent-reported child anxiety, and salivary cortisol levels in youth with autism spectrum disorder (ASD) with a wide range of intellectual abilities using a prospective design. Results showed that IQ at time 1 (T1) positively predicted parent-reports of child anxiety at time 2 (T2); however, IQ at T1 negatively predicted cortisol levels from saliva samples taken at a research laboratory at T2. Parent reports of child anxiety at T1 and T2 were not associated with cortisol levels at T2. Implications for the assessment of anxiety in youth with ASD are discussed.

Salivary Electrochemical Cortisol Biosensor Based on Tin Disulfide Nanoflakes

Cortisol, a steroid hormone, is secreted by the hypothalamic-pituitary-adrenal system. It is a well-known biomarker of psychological stress and is hence known as the "stress hormone." If cortisol overexpression is prolonged and repeated, dysfunction in the regulation of cortisol eventually occurs. Therefore, a rapid point-of-care assay to detect cortisol is needed. Salivary cortisol electrochemical analysis is a non-invasive method that is potentially useful in enabling rapid measurement of cortisol levels. In this study, multilayer films containing two-dimensional tin disulfide nanoflakes, cortisol antibody (C-M_ab), and bovine serum albumin (BSA) were prepared on glassy carbon electrodes (GCE) as BSA/C-M_ab/SnS₂/GCE, and characterized using electrochemical impedance spectroscopy and cyclic voltammetry. Electrochemical responses of the biosensor as a function of cortisol concentrations were determined using cyclic voltammetry and differential pulse voltammetry. This cortisol biosensor exhibited a detection range from 100 pM to 100 μM, a detection limit of 100 pM, and a sensitivity of 0.0103 mA/Mcm² (R² = 0.9979). Finally, cortisol concentrations in authentic saliva samples obtained using the developed electrochemical system correlated well with results obtained using enzyme-linked immunosorbent assays. This biosensor was successfully prepared and used for the electrochemical detection of salivary cortisol over physiological ranges, based on the specificity of antibody-antigen interactions.