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• The objective of our study was to compare the response of autonomic system parameters (blood pressure, ECG, heart rate variability) in healthy subjects while listening to Indian classical music of different fractal qualities. • To quantify the complexity of a musical phrase we have used the Higuchi fractal dimension. • Indian classical music has the unique quality of slow transition betwen notes, with consequent changes in dimensions of the string being played, which we have quantified in the study. • 25 healthy volunteers were recruited, all between 18 and 35 years of age. The subjects were randomised into three groups: sinewave, low fractal music and high fractal music. • Electrocardiogram (ECG) and Non invasive BP (NIBP) leads were placed and continuous measurements started 10 min prior to intervention. At 0 min, the standardised musical intervention/ control was played. • During intervention, the fractal dimension of the BP waveform showed a significant difference between subjects of high fractal group and low fractal group. The Hurst exponent and sample entropy of the waveform was also measured. • In addition, the increment in heart rate variability during intervention showed an increasing trend from high to low fractal to sinewave. • Whether the changes are due to direct contact with source of music or through a cerebral mechanism can be ascertained by further studies. Music is an external stimulus that affects physiological systems; both the quality of music and the resultant physiological changes can be quantified, which presents an unique opportunity. To quantify the complexity of a musical phrase we have used the Higuchi fractal dimension. We then compared the response of autonomic system (blood pressure, ECG, heart rate variability) in healthy subjects while listening to Indian classical music of different fractal qualities. Indian classical music has the unique quality of slow transition between notes, with consequent changes in dimensions of the string being played, which we have quantified. 25 healthy volunteers were recruited, all 18–35 years of age; the subjects were randomised into three groups: sinewave, low fractal and high fractal, depending on the type of musical intervention. The subjects were placed in a quiet room and asked to perform deep breathing exercises for relaxation. Electrocardiogram (ECG) and Non invasive BP (NIBP) leads were placed and continuous measurements started 10 min prior to intervention. At 0 min, the standardised musical intervention/ control was played. During intervention, the fractal dimension of the BP waveform showed a significant difference between subjects of high fractal group and low fractal group. In addition, the increment in heart rate variability (measured by standard parameters) during intervention showed an increasing trend from high to low fractal to sinewave. Whether the changes are due to direct contact with source of music or through a cerebral mechanism can be ascertained by further studies. [ABSTRACT FROM AUTHOR]

• Implementation of IT2-FLCP-PID control scheme for mean arterial blood pressure regulation. • Automatic control of SNP drug administration in order to meet the required performance specifications. • The controller parameters and scaling gains are obtained with a recent meta-heuristic optimization technique CSA. • Comparison is done with T1-FLC-PID and conventional PID controllers. • Robustness testing is done for parameter variations and noise rejection. The main aim of this work is to present an optimal and robust controller design in order to improve the drug infusion to the automatic control of mean arterial blood pressure in conditions like critically-ill or post-operative or anaesthesia administration. The physiological systems also have uncertainty issues such as parameter variations with time or external disturbances and noise. Therefore, a controlled drug administration is necessary to regulate the mean arterial blood pressure of a person during surgery/observation. Over the years, the proportional-integral-derivative (PID) controller is the most commonly used controller in industries due to its easy structure and simplicity. However, this controller does not meet the desired performance with the complex and uncertain plants. Therefore, a robust controller is required to regulate the physiological variables that are uncertain in nature and can affect the human life. In this work, a hybrid control scheme consisting of an interval type-2-fuzzy logic controller which acts as pre-compensator to the traditional PID controller is presented, to regulate the mean arterial blood pressure of a patient by administering the drug sodium nitroprusside in a controlled manner. An effective and well-established nature-inspired optimization technique namely cuckoo search algorithm is employed for obtaining the optimal parameters for the presented scheme. Simulation results are presented to show the effectiveness and robustness of proposed interval type-2-fuzzy logic controller based PID controller scheme, for maintaining the mean arterial pressure to 100 mmHg within considerable limit through SNP infusion. The results are further compared with other two controllers namely type-1 fuzzy logic based PID and traditional PID controllers for the parameter variations and external noise. In this study, the proposed interval type-2-fuzzy logic controller pre-compensator based PID controller provides an effective control than traditional type-1 fuzzy logic based control scheme and PID controller in terms of overshoot, settling-time and error which are the prime performance objectives of the closed-loop controlled drug delivery of human blood pressure. The presented study provides a firm base for initial design considerations for development of a low-cost closed-loop drug delivery system for blood pressure regulation. [ABSTRACT FROM AUTHOR]

Lower body negative pressure (LBNP) has been employed in multiple countermeasure protocols against post spaceflight orthostatic hypotension. However, protocols utilizing oscillatory LBNP (oLBNP) have not been explored in this regard. oLBNP has shown promise in few studies to have good tolerance in conditions of hypovolemic stress and since the negative suction is only phasic, the extravascular fluid shifts associated with negative suction are also hypothesized to be less. Our study addressed the paucity of information on oLBNP by investigating the cardiovascular and neurohormonal effects of oLBNP of −15 and −45 mm Hg in 40 healthy adult males (mean age = 29.6 ± 4.7 years, BMI = 25.1 ± 3.6 kg/m2). After supine rest of 10 min (baseline), oLBNP was applied at −15 mm Hg and −45 mm Hg for 10 min each with a gap of 10 min. Blood sample for neurohormonal analysis was collected at the end of baseline and after each oLBNP exposure. Blood pressure, heart rate, respiratory rate and end tidal CO 2 (EtCO 2) were recorded for the entire duration. Serum angiotensin II (ATII), antidiuretic hormone (ADH) and atrial natriuretic peptide (ANP) were analyzed using ELISA. On comparison with the baseline [SBP: 114 ± 2.38, MBP: 75.8 ± 2.16 mm Hg] there was a significant fall in SBP on application of −15 mm Hg as well as −45 mm Hg oLBNP[-15 oLBNP: 107.4 ± 2.34 mm Hg; −45 oLBNP: 105.3 ± 2.28 mm Hg], while there was no significant difference observed in the DBP. There was a significant increase in the heart rate at both −15 [77.29(72.75–85.65) BPM] and −45 mm Hg [81.29 (73.93–86.09) BPM] oLBNP as compared to the baseline [70.41(64.32–79.80) BPM]. No significant difference in the serum ATII, ADH and ANP after 10 min of application of −15 or −45 mm Hg oLBNP as compared to baseline was observed. In conclusion, oLBNP induced legward pooling of blood causes a fall in the blood pressure which initiates the neural reflex mechanisms, most important being the baroreflex and the cardiopulmonary reflex. However, since there was no significant difference in the serum ATII, ADH and ANP from baseline, this suggests that 10 min oLBNP up to −45 mm Hg results in recruitment of cardiovascular neural reflex response but it does not evoke neurohormonal responses which mediate long term volume changes. • -45 mm Hg Oscillatory LBNP (oLBNP) evoked blood pressure drop & elevation in heart rate. • However, the serum ATII, ADH and ANP remain unchanged after the same protocol. • oLBNP causes recruitment of cardiovascular reflexes but not hormonal response. [ABSTRACT FROM AUTHOR]

Background: Autonomic dysfunction is common in children with Rett syndrome. They usually manifest with agitation, persistent screaming, constipation, gastroesophageal reflux, aerophagia, hyperventilation, and breath-holding episodes. Cardiovascular autonomic dysfunction may result in fatal a arrhythmia. Many of these events are mistaken for seizures and treated with antiepileptics.Methods: The present study was conducted in a tertiary care teaching hospital in north India for more than a six month period. MeCP2 mutation positive, 24 cases with Rett syndrome and 24 age-matched healthy girls were evaluated for cardiovascular autonomic dysfunction (heart rate variability, head-up tilt test, and cold pressor test).Results: The mean age was 9.06 years (±3.4) and 9.75 years (±3.13) for patients and control subjects, respectively. The heart rate variability contributed independently by parasympathetic and sympathetic nervous system was significantly reduced in cases compared with control subjects (P = 0.033 and P = 0.001, respectively). There was significant sympathovagal imbalance with sympathetic overactivity in cases compared with control subjects (P = 0.001). The mean longest QTc interval was significantly prolonged in cases compared with control subjects (P = 0.001). Cold pressor test and head-up tilt test could be done in 16 Rett syndrome patients (because of poor cooperation) and in all 24 control subjects. The change in blood pressure during cold pressor test and head-up tilt test was not significantly different in cases and control subjects.Conclusions: Children with Rett syndrome exhibited significant cardiovascular autonomic dysfunction in the form of sympathetic overactivity, parasympathetic underactivity, and sympathovagal imbalance. These findings have potentially important therapeutic- and outcome-related implications. [ABSTRACT FROM AUTHOR]