Levels of salivary immunoglobulin A under psychological stress and its relationship with rumination and five personality traits in medical students

Background and Objectives: The measurement of salivary immunoglobulin A is a useful and non-invasive method for measuring stress. Personality traits and rumination act as possible mediators in the relationship between psychological stressors and the immune system. This study was aimed to evaluate the levels of salivary IgA under psychological stress and its relationship with rumination and five personality traits in medical students. Methods: In this cross- sectional study, 45 medical students who intended to participate in the final exam were selected by simple random sampling. Two months before the exam, in the basal conditions, the NEO Personality Inventory-Short Form and Emotional Control Questionnaire (ECQ) were completed. Saliva samples were taken from students in both the basal conditions and exam stress conditions. Salivary IgA was measured by an ELISA test. Data was analyzed using paired samples T-test, Pearson correlation analysis, and stepwise regression. Results: A significant reduction of salivary IgA levels was found in exam stress conditions. Also, a significant negative correlation was found between traits of neuroticism and rumination with salivary IgA, as well as a significant positive correlation between of openness to experience and emotional inhibition with salivary IgA. Openness to experience and emotional inhibition may predict a substantial variance (34%) of salivary IgA under exam stress. Conclusions: Salivary IgA is reduced in response to exam stress. In addition, the rumination and personality traits may reduce or increase stress effects on the immune system, particularly the salivary IgA.

Cerebrotendinous xanthomatosis with bradyphrenia and psychiatric disorders: a case with 18F-FDG PET imaging and a literature review

Background and Objectives: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive lipid-storage disease caused by mutations in the CYP27A1. The purpose of this study is to determine the clinical characteristics, neuroimaging and mutation detect in a family with CTX systematically. Methods: Collecting history materials and detecting the routine clinical biochemical tests and imaging examination, and for the first time taking the whole body positron emission tomography (PET)-CT examination for probed in the world to research abnormal metabolism activities in CTX. To observe the effect of treatment with chenodeoxycholic acid (CDCA) and stains before and after the intervention, using serum lipid level detection and neuropsychological evaluation. Genetic testing was carried out to screen the nine exons and exon-intron boundaries about 200-300bq of CYP27A1. Results: A 37-year-old woman with typical clinical characteristics of CTX. Magnetic resonance imaging (MRI) of brain showed bilateral lesions in the dentate nucleus of the cerebellum, then, PET images revealed multiple abnormal hypermetabolism areas at distal tendon, and multifocal areas of hypometabolism in bilateral sides of cerebellar hemispheres, the frontal lobe and temporal lobe. Histopathology reveals accumulation of xanthoma cells and dispersed lipid crystal clefts in xanthomas. In genetic analysis, it shown an insertion of cytosine (77-78insC) located in the first exon of CYP27A1 in the proband. Conclusions: We found that a Chinese patient presented a typical clinical feature of CTX along with clear correlation on both structural and functional imaging had a novel mutation in the CYP27A1 gene.