Detecting cannabis use on the human skin surface via an electronic nose system.

The most commonly used drug testing methods are based on the analysis of hair and urine using gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry or immunoassay screening. These methods are time-consuming and partly expensive. One alternative method could be the application of an "electronic nose" (eNose). We have developed an eNose to detect directly on the human skin surface metabolic changes in the human body odor caused by cannabis consumption. Twenty cannabis-smoking and 20 tobacco-smoking volunteers were enrolled in this study. For the sensor signal data processing, two different methods were applied: Principle component analysis (PCA) with discriminant analysis, and the method of pattern recognition with subsequent support vector machines (SVM) processing. The PCA analysis achieved a correct classification of 70%, whereas the SVM obtained an accuracy of 92.5% (sensitivity 95%, specificity 90%) between cannabis-consuming volunteers and tobacco-smoking subjects. This study shows evidence that a low-cost, portable and fast-working eNose system could be useful for health protection, security agencies and for forensic investigations. The ability to analyze human body odor with an eNose opens up a wide field for diagnosing other drugs and also various diseases.

Rhythmical massage improves autonomic nervous system function: a single-blind randomised controlled trial.

BACKGROUND: Rhythmical massage therapy (RMT) is a massage technique used in anthroposophic medicine. OBJECTIVE: The authors aimed to investigate the physiological action of RMT on the cardiovascular system by analysing heart rate variability (HRV). DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: This study was a randomised, controlled and single-blinded trial, involving 44 healthy women (mean age: (26.20 ±â€¯4.71) years). The subjects were randomised to one of three arms: RMT with aromatic oil (RA), RMT without aromatic oil (RM) or standardised sham massage (SM). In the study the subjects were exposed to a standardised stress situation followed by one of the study techniques and Holter electrocardiograms (ECGs) were recorded for 24 h. MAIN OUTCOME MEASURES: HRV parameters were calculated from linear (time and frequency domain) and nonlinear dynamics (symbolic dynamics, Poincare plot analysis) of the 24-h Holter ECG records. RESULTS: Short- and long-term effects of massage on autonomic regulation differed significantly among the three groups. Immediately after an RMT session, stimulation of HRV was found in the groups RA and RM. The use of an aromatic oil produced greater short-term measurable changes in HRV compared with rhythmic massage alone, but after 24 h the effect was no longer distinguishable from the RM group. The lowest stimulation of HRV parameters was measured in the SM group. CONCLUSION: RMT causes specific and marked stimulation of the autonomic nervous system. Use of a medicinal aromatic oil had only a temporary effect on HRV, indicating that the RM causes the most relevant long-term effect. The effect is relatively specific, as the physiological effects seen in the group of subjects who received only SM were considerably less pronounced. TRIAL REGISTRATION: Registration trial DRKS00004164 on DRKS.

Blood Pressure and Heart Rate Variability to Detect Vascular Dysregulation in Glaucoma.

Purpose. To investigate blood pressure and heart rate variability in patients with primary open-angle glaucoma (POAG) to detect disturbed blood pressure regulation. Methods. Thirty-one patients with POAG (mean age 68 ± 10 years) and 48 control subjects (mean age 66 ± 10 years) were included in a prospective study. Continuous blood pressure and heart rate were simultaneously and noninvasively recorded over 30 min (Glaucoscreen, aviant GmbH, Jena, Germany). Data were analyzed calculating univariate linear (time domain and frequency domain), nonlinear (Symbolic Dynamics, SD) and bivariate (Joint Symbolic Dynamics, JSD) indices. Results. Using nonlinear methods, glaucoma patients were separated with more parameters compared to linear methods. In POAG, nonlinear univariate indices (pW113 and pW120_Sys) were increased while the indices pTH10_Sys and pTH11_Sys reflect a reduction of dominant patterns. Bivariate indices (JSDdia29, JSDdia50, and JSDdia52; coupling between heart rate and diastolic blood pressure) were increased in POAG. The optimum set consisting of six parameters (JSDdia29, JSDdia58, pTH9_Sys, pW231, pW110_Sys and pW120_Sys) revealed a sensitivity of 83.3% and specificity of 80.6%. Conclusions. Nonlinear uni- and bivariate indices of continuous recordings of blood pressure and heart rate are altered in glaucoma. Abnormal blood pressure variability suggests disturbed autonomic regulation in patients with glaucoma.

Altered autonomic regulation as a cardiovascular risk marker for patients with sudden sensorineural hearing loss.

OBJECTIVES: To measure autonomic nervous system function after idiopathic sudden sensorineural hearing loss (ISSHL). STUDY DESIGN: Diagnostic prospective cohort single-center study. SETTING: Tertiary referral university hospital. PATIENTS: Twenty-three adult patients with ISSHL and 10 normal-hearing control patients without ISSHL (CON) matched with respect to age, sex, hypertension, and medication. MAIN OUTCOME MEASURES: Bivariate analysis of autonomic regulation (ISSHL versus CON) using 30-minute heart rate (HR) and systolic and diastolic blood pressure (BP) time series at baseline, based on cardiovascular coupling, HR and BP regulatory patterns, high-resolution coupling analysis based on joint symbolic dynamics (High-Resolution Joint Symbolic Dynamics). INTERVENTION: No intervention. RESULTS: Multivariate discrimination between ISSHL and CON achieved values of area under the receiver operator characteristic curve = 95.5, sensitivity = 90.9%, and specificity = 88.9%. Independent from medication and hypertension increased the complexity of nonlinear HR regulation and reduced cardiovascular coupling of ISSHL patients and independent from hypertension altered nonlinear systolic and diastolic BP regulation. Coupling patterns are characterized by a less pronounced strong and fast decrease of systolic BP when HR increases and rapidly changes in ISSHL patients. Disturbed BP modulation and complexity by impaired baroreflex activities resulting in short-term BP fluctuations, altered peripheral resistance, and reduced cochlear blood flow. Increased values for the pulse wave velocity in the aorta and carotid-femoral were early indicators that the elasticity of the arteries might be restricted in ISSHL patients. CONCLUSION: ISSHL patients show an altered autonomic regulation. At least a subgroup of ISSHL patients seems to exist where a vascular impairment might play an important role in the pathogenesis of this disease.

Improvement of circadian rhythm of heart rate variability by eurythmy therapy training.

Background. Impairment of circadian rhythm is associated with various clinical problems. It not only has a negative impact on quality of life but can also be associated with a significantly poorer prognosis. Eurythmy therapy (EYT) is an anthroposophic movement therapy aimed at reducing fatigue symptoms and stress levels. Objective. This analysis of healthy subjects was conducted to examine whether the improvement in fatigue symptoms was accompanied by improvements in the circadian rhythm of heart rate variability (HRV). Design. Twenty-three women performed 10 hours of EYT over six weeks. Electrocardiograms (ECGs) were recorded before and after the EYT trial. HRV was quantified by parameters of the frequency and time domains and the nonlinear parameters of symbolic dynamics. Results. The day-night contrast with predominance of vagal activity at night becomes more pronounced after the EYT training, and with decreased Ultralow and very low frequencies, the HRV shows evidence of calmer sleep. During the night, the complexity of the HRV is significantly increased indicated by nonlinear parameters. Conclusion. The analysis of the circadian patterns of cardiophysiological parameters before and after EYT shows significant improvements in HRV in terms of greater day-night contrast caused by an increase of vagal activity and calmer and more complex HRV patterns during sleep.

Quantification of autonomic regulation in patients with sudden sensorineural hearing loss.

Previous studies have proposed varying causes for idiopathic sudden sensorineural hearing loss (SSNHL), including vascular occlusion, ruptured inner ear membrane, acoustic tumours and circulatory disturbances in the inner ear. The objective of this study was to characterise the autonomic regulation in 19 SSNHL patients in comparison to 19 healthy age-gender matched normal-hearing control subjects (CON) in order to improve the diagnostics of vascular caused hearing loss in SSNHL patients. A high-resolution short-term electrocardiogram (ECG) and the continuous noninvasive blood pressure signal were simultaneously recorded under resting conditions (30min). Linear and nonlinear indices of heart rate- and blood pressure variability (HRV, BPV) were calculated to characterise autonomic regulation. The results showed that HRV analysis did not produce significantly different results between SSNHL and CON, whereas linear and nonlinear BPV indices showed significant differences between both groups (p<0.01). This study was the first to show an altered cardiovascular regulation in SSNHL patients when compared to CON subjects, based on continuous blood pressure analysis. This was characterised by reduced variability, complexity and dynamics of blood pressure time series in SSNHL. These findings may contribute to an improved classification of the controversially discussed causes of SSNHL and, in addition, may lead to improved diagnostic strategies for a subgroup of SSNHL patients whose hearing loss is caused by cardiovascular factors.

Improvement of heart rate variability by eurythmy therapy after a 6-week eurythmy therapy training.

BACKGROUND: Eurythmy therapy (EYT) is a mind-body therapy used in anthroposophic medicine. Recently, the authors were able to show that at comparable workloads, EYT stimulated heart rate variability (HRV) whereas conventional ergometer training attenuated HRV. Furthermore, a long-term improvement of quality of life (QoL) and stress coping strategies by EYT could be shown. OBJECTIVE: This study aimed to evaluate the long-term effects of EYT training on HRV. DESIGN: A total of 23 healthy women (mean age = 44.57 ± 8.04 years) performed 10 hours of EYT over a period of 6 weeks. Electrocardiograms were recorded before and after the EYT trial. HRV was quantified by the extent of high (HF), low (LF), very low (VLF), and ultra low frequency (ULF) oscillations of heart rate. RESULTS: Autonomic regulation was significantly changed following the EYT training compared with baseline. Especially the proportion referring to the total power (P) of HF/P and LF/P increased, whereas ULF/P and (ULF+VLF)/P decreased after the training period. CONCLUSION: EYT shifted the autonomic regulation proportionally referring to the total power mainly caused by changes of ULF and VLF components of HRV. The LF and HF spectral components were also decreased following EYT while their proportion in relation to the total variance of the power spectrum was increased. The proportional enhancement of the higher frequency and the decrease of the ULF and VLF components are probably an indicator of an improvement of autonomic regulation processes by more relaxed physical activity after the EYT training, thus supporting the plausibility of the improved QoL and better stress coping strategies.

Discrimination and characterization of breath from smokers and non-smokers via electronic nose and GC/MS analysis.

The objective of this study was to prove the general applicability of an electronic nose for analyzing exhaled breath considering the dependency on smoking. At first, odor compounds from spices (n=6) were detected via the electronic nose and further characterized and classified with gas chromatography/ mass spectrometry to demonstrate the principle ability of the electronic nose. Then, the exhaled breath from smokers and non-smokers were analyzed to prove the influence of smoking on breath analyses with the electronic nose. The exhaled breath was sampled from 11 smokers and 11 non-smokers in a special sampling bag with the mounted sensor chip of the electronic nose. Additionally, solid phase micro-extraction (SPME) technique was established for detection of the specific chemical compounds with gas chromatography and mass spectrometry (GC/MS). For analyses of the sensor signals the principle component analysis (PCA) was applied and the groups were differentiated by linear discriminant function analysis. In accordance to the discrimination between the different spices and between smokers and non-smokers the PCA analysis leads to an optimum accuracy of 100%. The results of this study show that an electronic nose has the ability to detect different changes of odor components and provides separation of smoking side effects in smelling different diseases.