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Objective: The dysfunction of the autonomic nervous system investigated in Children with Autism compared with healthy one. Cardiovascular autonomic disturbances are possibly associated with the pathogenesis of Autism in children. The purpose of this study is to use the spectral and coherence analysis of heart rate variability signal (HRV), respiration signal and peripheral blood flow signal (PBF) to assess the autonomic activity of normal children and children with Autism for the clinical usefulness of the applied methods of signal processing and timefrequency analysis for screening and treatment of Autism in children.Methods: Twenty four children who had Autism and who were not taking any medications and Twenty three age and sex matched controls (Children) were participated in this study at Department of Neurology at Johns Hopkins Hospital, Baltimore, MD, USA and Regional Medical Center, Cookeville, TN, USA. PBF and respiration signals as well as HRV signal derived from Electrocardiogram (ECG) were measured during supine and standing positions. Autopower, cross power and coherence spectra were produced to investigate the sympathetic and parasympathetic activity in both groups. Results:The results clearly indicate that in children with Autism, the coherence values are less than in control group in both low frequency (LF) and high frequency (HF) bands at coherence spectra between HRV and PBF as well as HRV and respiration in both supine and standing position. Also, the ratio of amplitude at nearly frequency of 0

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Background: Chest ultrasonography has recently been shown to be useful for the non-invasive assessment of extravascular lung water, Patients on maintenance hemodialysis are characterized by a condition of volume overload, these patients represent a unique model in which volume overload can be evaluated before and after a rapid fluid clearance determined by the dialytic session. Our aim of work was to assess efficacy of lung ultrasound in detecting extravascular lung water and volume over load. Methods: Forty patients known as chronic renal failure patients on regular hemodialysis for more than 6 months were subjected to full history taking and physical examination, laboratory studies, echocardiography, and lung ultrasound, before and after dialysis session. Lung ultrasound and inferior vena cava measurements were performed immediately before and after dialysis. A standard echocardiography probe was used for the detection of lung comets. Examinations were performed in the supine position. Scanning of the anterior and lateral chest was performed on both sides of the chest, Lung comets (B lines) were calculated in 2 different planes both right and left (mid clavicular, mid axillary), to make total of 8 intercostal spaces examined for lung comets. Results: Our study showed highly significant reduction of pulmonary B-lines (ULCs) following dialysis, significant linear regression between B-lines percentage reduction (delta B-lines %) and delta weight (kg), significant reduction in end inspiratory and end expiratory vena cava diameter, Also our study showed significant association between expiratory IVC diameter before dialysis and accumulated weight in respect to dry weight, but did not show significant association between expiratory vena cava diameter after dialysis and residual weight in respect to dry weight. Conclusion: Ultrasound performed at the bedside can detect lung water and intravascular overload and their reduction after dialysis in yet asymptomatic patients.

The main objective of this paper is to assess the autonomic function of healthy subjects and diabetic patients by using autopower spectra and measurement of gain frequency response between breathing signals at different rates as input and heart rate variability signals (HRV) as output.Twenty healthy subjects (39± 3.6) years old and twenty one diabetic patients (41±2.4) years old participated in this study . The subject lies on a bed where Electrocardiogram (ECG) , heart rate variability signals (HRV) extracted from ECG and respiration signals at different breathing rates were measured and recorded. The autopower spectra of breathing rates and HRV signals were produced using the auto-regressive method. The gain frequency response for both healthy and diabetic groups was obtained . The effect of respiration signals at different rates on the auto-power of HRV signals significant specially for healthy subjects on a rate of 6 cycle /min (6 c pm or 0.1 Hz). However, this effect is reduced in all diabetic patients examined. The gain response of healthy group shows high gain with two peaks at 0.1 Hz and 0.2 Hz and high standard deviation (SD).