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Autism spectrum disorder (ASD) is a neurodevelopmental disorder afflicting about one in every 68 children. It is behaviorally diagnosed based on a triad of symptoms, including impairment in communication, impairment in sociability and abnormal and stereotypic behavior. The subjectivity of behavioral diagnosis urges the need for clinical biomarker tests to improve and complement ASD diagnosis and treatment. Over the past two decades, researchers garnered a broad range of biomarkers associated with ASD and often correlating with the severity of ASD, which includes metabolic and genetic biomarkers or neuroimaging abnormalities. Metabolic biomarkers are either involved in key pathways such as a trans-sulfuration pathway or produced due to the derangement of these pathways in the case of oxidative stress. Recent studies reported several genetic abnormalities related to ASD, encompassing various mechanisms, from copy number variations (CNVs) and single nucleotide polymorphisms (SNPs) to chromosomal anomalies. However, it is still premature to consider these genetic variants as true biomarkers for ASD, due to their low reproducibility and regional-specific nature. Herein, we comprehensively review state of the art about major biomarkers reported in ASD and the association of some biomarkers with ASD symptoms and severity. It is important to establish those biomarkers to be able to help in the diagnosis and to optimize the treatment of ASD.  相似文献   
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Ocular pulse amplitude (OPA) is defined as the difference between maximum and minimum intraocular pressure (IOP) during a cardiac cycle. Average values of OPA range from 1 to 4 mmHg. The purpose of this investigation is to determine the source of an irregular IOP waveform with elevated OPA in a 48-year-old male. Ocular pressure waveforms had an unusual shape consistent with early ventricular contraction. With a normal IOP, OPA was 9 mmHg, which is extraordinarily high. The subject was examined by a cardiologist and was determined to be in ventricular bigeminy. In addition, he had bounding carotid pulses and echocardiogram confirmed aortic insufficiency. After replacement of the aortic valve, the bigeminy resolved and the ocular pulse waveform became regular in appearance with an OPA of 1.6–2.0 mmHg. The ocular pressure waveform is a direct reflection of hemodynamics. Evaluating this waveform may provide an additional opportunity for screening subjects for cardiovascular anomalies and arrhythmias.  相似文献   
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Background: Mesenchymal stem cells (MSCs) were isolated from various sources, including various types of tumors. However choosing an appropriate isolation method is an important step in obtaining cells with optimal quality and yield in companion with economical considerations. The purpose of this study was to isolate more pure MSCs from human breast tumor tissue by a modified explant culture method.

Methods and Materials: The tumor tissues (n = 8) were cut into 1 to 3-mm cube-like pieces (explant). Each explant was placed in a well of 24-well format plates, cultured in Dulbecco’s Modified Eagle’s medium (DMEM), and maintained at 37°C with 5% humidified incubator. Morphological phenotypes of the cells were surveyed by an inverted microscope and wells with rather homogenous fibroblast-like morphology cell were considered as positive and selected for more expansion and characterization.

Results: A total of 185 wells, 63.7% of wells were positive that were chosen for expansion. Flowcytometry analysis demonstrated that isolated cells were positive for CD73, CD44, CD29, CD105, and CD90 but negative for CD11b, CD45, CD34, and HLA?DR. In addition, cells possessed the capability of multipotential differentiation into osteoblasts and adipocytes.  相似文献   
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Intratumoral hemorrhage within a myxopapillary ependymoma of the conus medullaris and cauda equina is rare. Most patients with myxopapillary ependymoma present insidiously, but they may present with hemorrhage or cauda equina syndrome. Limited number of case reports available has described this condition only in adult patients. We report our experience with intratumoral hemorrhage of myxopapillary ependymoma of the conus medullaris during weight lifting in a 15-year-old boy.  相似文献   
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Aim of the workThe aim of the present study was to measure the level of the chemokine CXC ligand 13 protein (CXCL13) in the plasma and unstimulated saliva of rheumatoid arthritis (RA) patients in order to find out its role in the disease activity and its relation to secondary Sjögren’s syndrome (sSS).Patients and methodsThe study was conducted on thirty rheumatoid arthritis patients attending the Outpatient Clinic of Rheumatology and Rehabilitation department of Ain shams University Hospitals. The patients’ group had been classified into group (1) which included fifteen RA patients associated with sSS diagnosed according to the American–European Consensus Group Classification Criteria and group (2) which included fifteen RA patients not associated with sSS. Ten healthy subjects were included as a control group. Patients were subjected to full history taking, clinical examination, and laboratory detection of CXCL13 level in the plasma and saliva of patients as well as the control groups using ELISA technique. Assessment of disease activity in RA patients was done using the disease activity score (DAS28).ResultsPlasma levels of CXCL13 were significantly higher in RA patients than control group (p < 0.001). Plasma levels of CXCL13 were significantly correlated with the RA disease activity (r = 0.677, p < 0.001) and disease duration (r = 0.406, p < 0.05), while the salivary levels were higher in those with sSS and correlated with sSS disease duration (r = 0.536, p < 0.05). A highly significant correlation was found between salivary CXCL13 and severity of sSS (r = 0.816, p < 0.001). Salivary levels of CXCL13 above 110 pg/ml may diagnose sSS with sensitivity 80% and specificity 84%.ConclusionThe results of this preliminary study point out the importance of CXCL13 as a marker for RA disease activity, its role in diagnosing sSS, and estimation of sSS severity.  相似文献   
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