Control moment gyro optimization study

Control moment gyro optimizatio

An Imaging Photoplethysmographic Analysis of the Effects of Internal Thoracic Artery Resection on Chest Wall Perfusion

A prospective, non-randomized observational study involving forty-nine patients undergoing coronary artery bypass surgery (CABG) with a unilateral harvesting of the internal thoracic artery (ITA) was carried out at the Department of Cardiac Surgery, Herzzentrum Dresden University hospital. Using a commercially available industrial-grade RGB camera and normal indoor lighting, the chest wall of the patients was scanned before surgery and in three follow-up measurements. The primary aim of this thesis was to show whether iPPG is sensitive enough to detect global signal changes after a major surgery – CABG in this case – and local signal changes due to the removal of the ITA, the main supply vessel of the chest wall. As a secondary aim, the thesis looked at subgroups of data to show if differences in signal existed between the colour channels of the RGB camera, subdivisions of the thorax and the surgical technique used as well as to show if demographic factors had an impact on signal strength. With mathematical programs developed by the Technical University Dresden, the scanned optical data was transformed into signal to noise ratios (SNR) used in imaging photoplethysmographic (iPPG) studies. The signal data was analysed in R and, based on a stepwise deletion, a multivariable mixed effects model was constructed. Adjusted versions of this model were used for the analysis of the subgroups of the data. Analysis of the data showed a significant decrease of iPPG signal strength after the CABG surgery with a steeper decrease and an attenuated recovery on the side of the ITA harvesting. Even though the signal variations were relatively small, using the models in this thesis, the differences were reliably detected by iPPG. The analysis of the data from the subdivisions of the chest and from patients’ groups determined by the surgical technique showed a caudo-cranial signal gradient on the ITA side twenty-four hours after the surgery and a stronger signal in the Pedicled group within twenty-four hours after the surgery. The latter calculations, however, were based on a possibly biased sample and should be verified using a controlled sample in prospective randomised study designs. Demographic factors showed no significant correlation with iPPG signal strength. iPPG was able to detect relatively small signal variations that could be associated with changes of cutaneous perfusion after major surgery. Future development could lead to non-invasive monitoring devices in the clinical practice of post-surgery care.:1. Introduction 1 1.1. Coronary Artery Bypass Grafting (CABG) 1 1.1.1. Historical Overview 1 1.1.2. Coronary Grafts 3 1.1.2.1. Pedicled vs. Skeletonised Grafts 4 1.2. Plethysmography 5 1.2.1. Air-Displacement Plethysmography (APG) 5 1.2.2. Strain Gauge Plethysmography (SGP) 6 1.2.3. Impedance Plethysmography (IPG) 6 1.2.4. Photoplethysmography (PPG) 7 1.2.5. Imaging Photoplethysmography (iPPG) 8 1.3. Hypothesis and Aim of the Thesis 11 2. Methods 13 2.1. Study Setting and Patients 13 2.2. Camera and Technical Setup 14 2.3. Recording Area and Regions of Interest 15 2.4. Signal Processing 16 2.5. Statistical Analysis 17 3. Results 19 3.1. Descriptive Properties of the Data 19 3.2. Signal Strength in the Three Colour Channels 20 3.3. Choosing a Multilevel Model 21 3.4. The Effect of the Major Surgery on the Signal Strength in the Three Colour Channels 22 3.5. The Effect of the Unilateral Resection of the Internal Thoracic Artery 25 3.6. Results from the Model Fitted to the Data 27 3.7. The Effect of Cofactors 28 3.8. Data from the Subdivisions of the Chest 29 3.9. The Effect of the Surgical Technique 31 4. Discussion 34 4.1. Signal Strength in the Red, Green and Blue Colour Channels 34 4.2. Signal from the Entire Chest Area 36 4.3. Signal from the Subdivisions of the Chest 37 4.4. The Influence of the Surgical Technique on Signal Strength 38 5. Conclusion 39 6. Abstract 41 7. Zusammenfassung 42 8. References 44 9. Appendix 60 10. Acknowledgements 82 11. Resume 83 Anlage 184 Anlage 2 85Eine prospektive, nicht randomisierte Studie mit neunundvierzig Patienten geplant für eine koronare Bypassoperation (CABG) mit einseitiger Präparation der Arteria thoracica interna (ITA) wurde im Herzzentrum Dresden, Universitätsklinikum durchgeführt. In einer präoperativen und in drei postoperativen Messungen wurde die Brustwand bei den untersuchten Patienten unter normaler Innenbeleuchtung mit Hilfe einer handelsüblichen, industriellen RGB Kamera untersucht. Das primäre Ziel der Arbeit war zu zeigen, ob iPPG als Messmethode genug Sensitivität besitzt um globale Signal-Veränderungen nach einem großen Eingriff – die CABG in diesem Fall – und lokale Signaländerung nach der Abnahme der ITA, die Hauptversorgungsarterie der Brustwand, zu erkennen. Als sekundäres Ziel der Arbeit war zu eruieren, ob iPPG Signaldifferenzen zwischen den Farbkanälen der RGB Kamera, den Brustwandaufteilungen und den Arten der ITA Präparation sowie nach den demographischen Faktoren detektieren konnte. Die gemessenen Daten wurden unter Verwendung von Eigentumsprogrammen der Technischen Universität Dresden in den, bei plethysmographischen Studien genutzten, Signal zu Geräusch Quotienten (SNR - signal to noise ratios) umgewandelt. Die gewonnenen Signaldaten wurden in R verarbeitet und durch Verwendung der Methode schrittweise Löschung wurde ein multivariables gemischte Effekte Modell erstellt. Angepasste Versionen dieses Modells wurden für die Analyse von Patientensubgruppen verwendet. Die Datenanalyse ergab eine signifikante Abschwächung des Signals nach der CABG, wobei die Thorax-Seite mit der ITA Präparation zeigte, im Vergleich mit der anderen Thorax-Seite, eine stärkere Abnahme und eine gedämpfte Rückbildung der Signalstärke. Obwohl die detektierte Signaländerungen relativ klein waren, sie konnten durch die entwickelten Modelle mittels iPPG zuverlässig detektiert werden. Die weitere Analyse der Daten aus den Brustwandaufteilungen und von Patientensubgruppen definiert nach Präparationsart der ITA zeigte auf der ITA Seite eine caudo-craniale Zunahme der Signalstärke ab vierundzwanzig Stunden und ein stärkeres Signal in der pedikulierten Präparationsgruppe bis vierundzwanzig Stunden nach der Operation. Allerdings, diese letztere Berechnungen wurden auf einem möglicherweise unausgewogenen Muster durchgeführt und sollten dementsprechend auf kontrollierten Mustern in prospektiven randomisierten Studien verifiziert werden. Die demographischen Faktoren hatten keiner signifikanten Korrelation mit der iPPG Signalstärke. Die iPPG war geeignet kleine Signaländerungen assoziiert mit den erwarteten Änderungen der dermalen Perfusion bei einem großen chirurgischen Eingriff zu detektieren. Weitere Entwicklung der Technologie kann die Anwendung dieses nicht-invasive Monitoringsverfahren in der klinischen postoperativen Patientenversorgung ermöglichen.:1. Introduction 1 1.1. Coronary Artery Bypass Grafting (CABG) 1 1.1.1. Historical Overview 1 1.1.2. Coronary Grafts 3 1.1.2.1. Pedicled vs. Skeletonised Grafts 4 1.2. Plethysmography 5 1.2.1. Air-Displacement Plethysmography (APG) 5 1.2.2. Strain Gauge Plethysmography (SGP) 6 1.2.3. Impedance Plethysmography (IPG) 6 1.2.4. Photoplethysmography (PPG) 7 1.2.5. Imaging Photoplethysmography (iPPG) 8 1.3. Hypothesis and Aim of the Thesis 11 2. Methods 13 2.1. Study Setting and Patients 13 2.2. Camera and Technical Setup 14 2.3. Recording Area and Regions of Interest 15 2.4. Signal Processing 16 2.5. Statistical Analysis 17 3. Results 19 3.1. Descriptive Properties of the Data 19 3.2. Signal Strength in the Three Colour Channels 20 3.3. Choosing a Multilevel Model 21 3.4. The Effect of the Major Surgery on the Signal Strength in the Three Colour Channels 22 3.5. The Effect of the Unilateral Resection of the Internal Thoracic Artery 25 3.6. Results from the Model Fitted to the Data 27 3.7. The Effect of Cofactors 28 3.8. Data from the Subdivisions of the Chest 29 3.9. The Effect of the Surgical Technique 31 4. Discussion 34 4.1. Signal Strength in the Red, Green and Blue Colour Channels 34 4.2. Signal from the Entire Chest Area 36 4.3. Signal from the Subdivisions of the Chest 37 4.4. The Influence of the Surgical Technique on Signal Strength 38 5. Conclusion 39 6. Abstract 41 7. Zusammenfassung 42 8. References 44 9. Appendix 60 10. Acknowledgements 82 11. Resume 83 Anlage 184 Anlage 2 8

Contact-free optical assessment of changes in the chest wall perfusion after coronary artery bypass grafting by imaging photoplethysmography

Imaging photoplethysmography (iPPG) is a contact-free monitoring of the cutaneous blood volume pulse by RGB (red-green-blue) cameras. It detects vital parameters from skin areas and is associated to cutaneous perfusion. This study investigated the use of iPPG to quantify changes in cutaneous perfusion after major surgery. Patients undergoing coronary artery bypass grafting (CABG) were scanned before surgery and in three follow-up measurements. Using an industrial-grade RGB camera and usual indoor lighting, a contact-free imaging plethysmogram from the chest was obtained. Changes of the iPPG signal strength were evaluated in view of both the operation itself as well as the unilateral preparation of the internal thoracic artery (ITA) for coronary artery grafting, which is the main blood source of the chest wall. iPPG signal strength globally decreased after surgery and recovered partially during the follow up measurements. The ITA preparation led to a deeper decrease and an attenuated recovery of the iPPG signal strength compared to the other side of the chest wall. These results comply with the expected changes of cutaneous perfusion after CABG using an ITA graft. iPPG can be used to assess cutaneous perfusion and its global changes after major surgery as well as its local changes after specific surgical procedures

Experimental study of the morphine de-addiction properties of Delphinium denudatum Wall.

BACKGROUND: Our aim was to explore the de-addiction properties of Delphinium denudatum Wall. in morphine dependent rats. METHODS: Charles Foster male albino rats were made morphine dependent by injecting morphine sulphate in increasing doses twice a day for 7 days. The spontaneous withdrawal signs observed 12 h after the last dose were quantified by the 'counted' and 'checked' signs. The drug (alcoholic extract of Delphinium denudatum) was administered p.o. in different regimen: a) single dose (700 mg/kg) 10 h before the first dose of morphine, b) single dose (700 mg/kg) 10 h after the last dose of morphine, c) multiple doses (350 mg/kg) along with morphine twice a day for 7 days. RESULT: Administration of Delphinium denudatum extract caused significant reduction in the frequency of counted signs as well as the presence of checked signs of morphine withdrawal. The maximum reduction was observed in regimen 'b' followed by regimen 'c' and 'a'. CONCLUSION: Delphinium denudatum Wall. significantly reduces the aggregate scores for all parameters in morphine withdrawal syndrome by central action and thus may prove to be an alternative remedy in morphine de-addiction

A stable aberrant immunophenotype characterizes nearly all cases of cutaneous T-cell lymphoma in blood and can be used to monitor response to therapy

BACKGROUND: Abnormal variations in the expression level of some commonly expressed T-cell antigens are a feature of many T-cell malignancies. METHODS: We sought to assess the frequency of such abnormal antigen expression by flow cytometry in peripheral blood (PB) samples from patients with mycosis fungoides (MF) and Sézary syndrome (SS). We correlated presence of morphologically identifiable tumor cells on PB smear with the frequency of abnormalities in the level of expression of CD3, CD4, CD7, CD8 and CD26. We also examined the degree of stability of these abnormal findings in tumor cells over the course of disease. The flow cytometric findings in 100 PB samples from 44 patients, including 38 who had multiple sequential PB samples (2–8 samples each), were assessed. RESULTS: Abnormalities were seen in the expression level of one or more T-cell markers in 41 cases (93%) including CD3 in 34% of patients, CD4 in 54%, CD26 in 86% and CD 45 in 40% (10 cases tested). In all but 2 cases, the abnormal T-cell immunophenotype remained similar over the course of treatment and correlated with the relative numbers of tumor cells counted on PB smear. CONCLUSIONS: Using a standard T-cell panel, stable phenotypically aberrant T-cell populations representing the tumor are detected in the vast majority of involved PB samples in MF/SS and can be used to monitor response to therapy

From Toxins Targeting Ligand Gated Ion Channels to Therapeutic Molecules

Ligand-gated ion channels (LGIC) play a central role in inter-cellular communication. This key function has two consequences: (i) these receptor channels are major targets for drug discovery because of their potential involvement in numerous human brain diseases; (ii) they are often found to be the target of plant and animal toxins. Together this makes toxin/receptor interactions important to drug discovery projects. Therefore, toxins acting on LGIC are presented and their current/potential therapeutic uses highlighted

Prediktory návratu k původní hmotnosti po ukončení 10-týdenní Dietní hubnutí programu (NUGENOB studie)

I would like to thank my consultant, MUDr. Jan Polák for his constructive criticism over my work and his comments for improvements from which I learned much and they were all well appreciated I would like to thank Eva Nemcova, fellow student of the 3rd faculty of Medicine for providing me with the anthropologic data of this study I would like to thank the whole department of Sports Medicine, lead by Doc. MUDr. Vladimír Štich, PhD. for providing me with the resources without which this thesis could not have been madeI would like to thank my consultant, MUDr. Jan Polák for his constructive criticism over my work and his comments for improvements from which I learned much and they were all well appreciated I would like to thank Eva Nemcova, fellow student of the 3rd faculty of Medicine for providing me with the anthropologic data of this study I would like to thank the whole department of Sports Medicine, lead by Doc. MUDr. Vladimír Štich, PhD. for providing me with the resources without which this thesis could not have been madeDepartment of Pathophysiology 3FM CUÚstav patofyziologie 3. LF UKThird Faculty of Medicine3. lékařská fakult

An Imaging Photoplethysmographic Analysis of the Effects of Internal Thoracic Artery Resection on Chest Wall Perfusion

A prospective, non-randomized observational study involving forty-nine patients undergoing coronary artery bypass surgery (CABG) with a unilateral harvesting of the internal thoracic artery (ITA) was carried out at the Department of Cardiac Surgery, Herzzentrum Dresden University hospital. Using a commercially available industrial-grade RGB camera and normal indoor lighting, the chest wall of the patients was scanned before surgery and in three follow-up measurements. The primary aim of this thesis was to show whether iPPG is sensitive enough to detect global signal changes after a major surgery – CABG in this case – and local signal changes due to the removal of the ITA, the main supply vessel of the chest wall. As a secondary aim, the thesis looked at subgroups of data to show if differences in signal existed between the colour channels of the RGB camera, subdivisions of the thorax and the surgical technique used as well as to show if demographic factors had an impact on signal strength. With mathematical programs developed by the Technical University Dresden, the scanned optical data was transformed into signal to noise ratios (SNR) used in imaging photoplethysmographic (iPPG) studies. The signal data was analysed in R and, based on a stepwise deletion, a multivariable mixed effects model was constructed. Adjusted versions of this model were used for the analysis of the subgroups of the data. Analysis of the data showed a significant decrease of iPPG signal strength after the CABG surgery with a steeper decrease and an attenuated recovery on the side of the ITA harvesting. Even though the signal variations were relatively small, using the models in this thesis, the differences were reliably detected by iPPG. The analysis of the data from the subdivisions of the chest and from patients’ groups determined by the surgical technique showed a caudo-cranial signal gradient on the ITA side twenty-four hours after the surgery and a stronger signal in the Pedicled group within twenty-four hours after the surgery. The latter calculations, however, were based on a possibly biased sample and should be verified using a controlled sample in prospective randomised study designs. Demographic factors showed no significant correlation with iPPG signal strength. iPPG was able to detect relatively small signal variations that could be associated with changes of cutaneous perfusion after major surgery. Future development could lead to non-invasive monitoring devices in the clinical practice of post-surgery care.:1. Introduction 1 1.1. Coronary Artery Bypass Grafting (CABG) 1 1.1.1. Historical Overview 1 1.1.2. Coronary Grafts 3 1.1.2.1. Pedicled vs. Skeletonised Grafts 4 1.2. Plethysmography 5 1.2.1. Air-Displacement Plethysmography (APG) 5 1.2.2. Strain Gauge Plethysmography (SGP) 6 1.2.3. Impedance Plethysmography (IPG) 6 1.2.4. Photoplethysmography (PPG) 7 1.2.5. Imaging Photoplethysmography (iPPG) 8 1.3. Hypothesis and Aim of the Thesis 11 2. Methods 13 2.1. Study Setting and Patients 13 2.2. Camera and Technical Setup 14 2.3. Recording Area and Regions of Interest 15 2.4. Signal Processing 16 2.5. Statistical Analysis 17 3. Results 19 3.1. Descriptive Properties of the Data 19 3.2. Signal Strength in the Three Colour Channels 20 3.3. Choosing a Multilevel Model 21 3.4. The Effect of the Major Surgery on the Signal Strength in the Three Colour Channels 22 3.5. The Effect of the Unilateral Resection of the Internal Thoracic Artery 25 3.6. Results from the Model Fitted to the Data 27 3.7. The Effect of Cofactors 28 3.8. Data from the Subdivisions of the Chest 29 3.9. The Effect of the Surgical Technique 31 4. Discussion 34 4.1. Signal Strength in the Red, Green and Blue Colour Channels 34 4.2. Signal from the Entire Chest Area 36 4.3. Signal from the Subdivisions of the Chest 37 4.4. The Influence of the Surgical Technique on Signal Strength 38 5. Conclusion 39 6. Abstract 41 7. Zusammenfassung 42 8. References 44 9. Appendix 60 10. Acknowledgements 82 11. Resume 83 Anlage 184 Anlage 2 85Eine prospektive, nicht randomisierte Studie mit neunundvierzig Patienten geplant für eine koronare Bypassoperation (CABG) mit einseitiger Präparation der Arteria thoracica interna (ITA) wurde im Herzzentrum Dresden, Universitätsklinikum durchgeführt. In einer präoperativen und in drei postoperativen Messungen wurde die Brustwand bei den untersuchten Patienten unter normaler Innenbeleuchtung mit Hilfe einer handelsüblichen, industriellen RGB Kamera untersucht. Das primäre Ziel der Arbeit war zu zeigen, ob iPPG als Messmethode genug Sensitivität besitzt um globale Signal-Veränderungen nach einem großen Eingriff – die CABG in diesem Fall – und lokale Signaländerung nach der Abnahme der ITA, die Hauptversorgungsarterie der Brustwand, zu erkennen. Als sekundäres Ziel der Arbeit war zu eruieren, ob iPPG Signaldifferenzen zwischen den Farbkanälen der RGB Kamera, den Brustwandaufteilungen und den Arten der ITA Präparation sowie nach den demographischen Faktoren detektieren konnte. Die gemessenen Daten wurden unter Verwendung von Eigentumsprogrammen der Technischen Universität Dresden in den, bei plethysmographischen Studien genutzten, Signal zu Geräusch Quotienten (SNR - signal to noise ratios) umgewandelt. Die gewonnenen Signaldaten wurden in R verarbeitet und durch Verwendung der Methode schrittweise Löschung wurde ein multivariables gemischte Effekte Modell erstellt. Angepasste Versionen dieses Modells wurden für die Analyse von Patientensubgruppen verwendet. Die Datenanalyse ergab eine signifikante Abschwächung des Signals nach der CABG, wobei die Thorax-Seite mit der ITA Präparation zeigte, im Vergleich mit der anderen Thorax-Seite, eine stärkere Abnahme und eine gedämpfte Rückbildung der Signalstärke. Obwohl die detektierte Signaländerungen relativ klein waren, sie konnten durch die entwickelten Modelle mittels iPPG zuverlässig detektiert werden. Die weitere Analyse der Daten aus den Brustwandaufteilungen und von Patientensubgruppen definiert nach Präparationsart der ITA zeigte auf der ITA Seite eine caudo-craniale Zunahme der Signalstärke ab vierundzwanzig Stunden und ein stärkeres Signal in der pedikulierten Präparationsgruppe bis vierundzwanzig Stunden nach der Operation. Allerdings, diese letztere Berechnungen wurden auf einem möglicherweise unausgewogenen Muster durchgeführt und sollten dementsprechend auf kontrollierten Mustern in prospektiven randomisierten Studien verifiziert werden. Die demographischen Faktoren hatten keiner signifikanten Korrelation mit der iPPG Signalstärke. Die iPPG war geeignet kleine Signaländerungen assoziiert mit den erwarteten Änderungen der dermalen Perfusion bei einem großen chirurgischen Eingriff zu detektieren. Weitere Entwicklung der Technologie kann die Anwendung dieses nicht-invasive Monitoringsverfahren in der klinischen postoperativen Patientenversorgung ermöglichen.:1. Introduction 1 1.1. Coronary Artery Bypass Grafting (CABG) 1 1.1.1. Historical Overview 1 1.1.2. Coronary Grafts 3 1.1.2.1. Pedicled vs. Skeletonised Grafts 4 1.2. Plethysmography 5 1.2.1. Air-Displacement Plethysmography (APG) 5 1.2.2. Strain Gauge Plethysmography (SGP) 6 1.2.3. Impedance Plethysmography (IPG) 6 1.2.4. Photoplethysmography (PPG) 7 1.2.5. Imaging Photoplethysmography (iPPG) 8 1.3. Hypothesis and Aim of the Thesis 11 2. Methods 13 2.1. Study Setting and Patients 13 2.2. Camera and Technical Setup 14 2.3. Recording Area and Regions of Interest 15 2.4. Signal Processing 16 2.5. Statistical Analysis 17 3. Results 19 3.1. Descriptive Properties of the Data 19 3.2. Signal Strength in the Three Colour Channels 20 3.3. Choosing a Multilevel Model 21 3.4. The Effect of the Major Surgery on the Signal Strength in the Three Colour Channels 22 3.5. The Effect of the Unilateral Resection of the Internal Thoracic Artery 25 3.6. Results from the Model Fitted to the Data 27 3.7. The Effect of Cofactors 28 3.8. Data from the Subdivisions of the Chest 29 3.9. The Effect of the Surgical Technique 31 4. Discussion 34 4.1. Signal Strength in the Red, Green and Blue Colour Channels 34 4.2. Signal from the Entire Chest Area 36 4.3. Signal from the Subdivisions of the Chest 37 4.4. The Influence of the Surgical Technique on Signal Strength 38 5. Conclusion 39 6. Abstract 41 7. Zusammenfassung 42 8. References 44 9. Appendix 60 10. Acknowledgements 82 11. Resume 83 Anlage 184 Anlage 2 8

An Imaging Photoplethysmographic Analysis of the Effects of Internal Thoracic Artery Resection on Chest Wall Perfusion

A prospective, non-randomized observational study involving forty-nine patients undergoing coronary artery bypass surgery (CABG) with a unilateral harvesting of the internal thoracic artery (ITA) was carried out at the Department of Cardiac Surgery, Herzzentrum Dresden University hospital. Using a commercially available industrial-grade RGB camera and normal indoor lighting, the chest wall of the patients was scanned before surgery and in three follow-up measurements. The primary aim of this thesis was to show whether iPPG is sensitive enough to detect global signal changes after a major surgery – CABG in this case – and local signal changes due to the removal of the ITA, the main supply vessel of the chest wall. As a secondary aim, the thesis looked at subgroups of data to show if differences in signal existed between the colour channels of the RGB camera, subdivisions of the thorax and the surgical technique used as well as to show if demographic factors had an impact on signal strength. With mathematical programs developed by the Technical University Dresden, the scanned optical data was transformed into signal to noise ratios (SNR) used in imaging photoplethysmographic (iPPG) studies. The signal data was analysed in R and, based on a stepwise deletion, a multivariable mixed effects model was constructed. Adjusted versions of this model were used for the analysis of the subgroups of the data. Analysis of the data showed a significant decrease of iPPG signal strength after the CABG surgery with a steeper decrease and an attenuated recovery on the side of the ITA harvesting. Even though the signal variations were relatively small, using the models in this thesis, the differences were reliably detected by iPPG. The analysis of the data from the subdivisions of the chest and from patients’ groups determined by the surgical technique showed a caudo-cranial signal gradient on the ITA side twenty-four hours after the surgery and a stronger signal in the Pedicled group within twenty-four hours after the surgery. The latter calculations, however, were based on a possibly biased sample and should be verified using a controlled sample in prospective randomised study designs. Demographic factors showed no significant correlation with iPPG signal strength. iPPG was able to detect relatively small signal variations that could be associated with changes of cutaneous perfusion after major surgery. Future development could lead to non-invasive monitoring devices in the clinical practice of post-surgery care.:1. Introduction 1 1.1. Coronary Artery Bypass Grafting (CABG) 1 1.1.1. Historical Overview 1 1.1.2. Coronary Grafts 3 1.1.2.1. Pedicled vs. Skeletonised Grafts 4 1.2. Plethysmography 5 1.2.1. Air-Displacement Plethysmography (APG) 5 1.2.2. Strain Gauge Plethysmography (SGP) 6 1.2.3. Impedance Plethysmography (IPG) 6 1.2.4. Photoplethysmography (PPG) 7 1.2.5. Imaging Photoplethysmography (iPPG) 8 1.3. Hypothesis and Aim of the Thesis 11 2. Methods 13 2.1. Study Setting and Patients 13 2.2. Camera and Technical Setup 14 2.3. Recording Area and Regions of Interest 15 2.4. Signal Processing 16 2.5. Statistical Analysis 17 3. Results 19 3.1. Descriptive Properties of the Data 19 3.2. Signal Strength in the Three Colour Channels 20 3.3. Choosing a Multilevel Model 21 3.4. The Effect of the Major Surgery on the Signal Strength in the Three Colour Channels 22 3.5. The Effect of the Unilateral Resection of the Internal Thoracic Artery 25 3.6. Results from the Model Fitted to the Data 27 3.7. The Effect of Cofactors 28 3.8. Data from the Subdivisions of the Chest 29 3.9. The Effect of the Surgical Technique 31 4. Discussion 34 4.1. Signal Strength in the Red, Green and Blue Colour Channels 34 4.2. Signal from the Entire Chest Area 36 4.3. Signal from the Subdivisions of the Chest 37 4.4. The Influence of the Surgical Technique on Signal Strength 38 5. Conclusion 39 6. Abstract 41 7. Zusammenfassung 42 8. References 44 9. Appendix 60 10. Acknowledgements 82 11. Resume 83 Anlage 184 Anlage 2 85Eine prospektive, nicht randomisierte Studie mit neunundvierzig Patienten geplant für eine koronare Bypassoperation (CABG) mit einseitiger Präparation der Arteria thoracica interna (ITA) wurde im Herzzentrum Dresden, Universitätsklinikum durchgeführt. In einer präoperativen und in drei postoperativen Messungen wurde die Brustwand bei den untersuchten Patienten unter normaler Innenbeleuchtung mit Hilfe einer handelsüblichen, industriellen RGB Kamera untersucht. Das primäre Ziel der Arbeit war zu zeigen, ob iPPG als Messmethode genug Sensitivität besitzt um globale Signal-Veränderungen nach einem großen Eingriff – die CABG in diesem Fall – und lokale Signaländerung nach der Abnahme der ITA, die Hauptversorgungsarterie der Brustwand, zu erkennen. Als sekundäres Ziel der Arbeit war zu eruieren, ob iPPG Signaldifferenzen zwischen den Farbkanälen der RGB Kamera, den Brustwandaufteilungen und den Arten der ITA Präparation sowie nach den demographischen Faktoren detektieren konnte. Die gemessenen Daten wurden unter Verwendung von Eigentumsprogrammen der Technischen Universität Dresden in den, bei plethysmographischen Studien genutzten, Signal zu Geräusch Quotienten (SNR - signal to noise ratios) umgewandelt. Die gewonnenen Signaldaten wurden in R verarbeitet und durch Verwendung der Methode schrittweise Löschung wurde ein multivariables gemischte Effekte Modell erstellt. Angepasste Versionen dieses Modells wurden für die Analyse von Patientensubgruppen verwendet. Die Datenanalyse ergab eine signifikante Abschwächung des Signals nach der CABG, wobei die Thorax-Seite mit der ITA Präparation zeigte, im Vergleich mit der anderen Thorax-Seite, eine stärkere Abnahme und eine gedämpfte Rückbildung der Signalstärke. Obwohl die detektierte Signaländerungen relativ klein waren, sie konnten durch die entwickelten Modelle mittels iPPG zuverlässig detektiert werden. Die weitere Analyse der Daten aus den Brustwandaufteilungen und von Patientensubgruppen definiert nach Präparationsart der ITA zeigte auf der ITA Seite eine caudo-craniale Zunahme der Signalstärke ab vierundzwanzig Stunden und ein stärkeres Signal in der pedikulierten Präparationsgruppe bis vierundzwanzig Stunden nach der Operation. Allerdings, diese letztere Berechnungen wurden auf einem möglicherweise unausgewogenen Muster durchgeführt und sollten dementsprechend auf kontrollierten Mustern in prospektiven randomisierten Studien verifiziert werden. Die demographischen Faktoren hatten keiner signifikanten Korrelation mit der iPPG Signalstärke. Die iPPG war geeignet kleine Signaländerungen assoziiert mit den erwarteten Änderungen der dermalen Perfusion bei einem großen chirurgischen Eingriff zu detektieren. Weitere Entwicklung der Technologie kann die Anwendung dieses nicht-invasive Monitoringsverfahren in der klinischen postoperativen Patientenversorgung ermöglichen.:1. Introduction 1 1.1. Coronary Artery Bypass Grafting (CABG) 1 1.1.1. Historical Overview 1 1.1.2. Coronary Grafts 3 1.1.2.1. Pedicled vs. Skeletonised Grafts 4 1.2. Plethysmography 5 1.2.1. Air-Displacement Plethysmography (APG) 5 1.2.2. Strain Gauge Plethysmography (SGP) 6 1.2.3. Impedance Plethysmography (IPG) 6 1.2.4. Photoplethysmography (PPG) 7 1.2.5. Imaging Photoplethysmography (iPPG) 8 1.3. Hypothesis and Aim of the Thesis 11 2. Methods 13 2.1. Study Setting and Patients 13 2.2. Camera and Technical Setup 14 2.3. Recording Area and Regions of Interest 15 2.4. Signal Processing 16 2.5. Statistical Analysis 17 3. Results 19 3.1. Descriptive Properties of the Data 19 3.2. Signal Strength in the Three Colour Channels 20 3.3. Choosing a Multilevel Model 21 3.4. The Effect of the Major Surgery on the Signal Strength in the Three Colour Channels 22 3.5. The Effect of the Unilateral Resection of the Internal Thoracic Artery 25 3.6. Results from the Model Fitted to the Data 27 3.7. The Effect of Cofactors 28 3.8. Data from the Subdivisions of the Chest 29 3.9. The Effect of the Surgical Technique 31 4. Discussion 34 4.1. Signal Strength in the Red, Green and Blue Colour Channels 34 4.2. Signal from the Entire Chest Area 36 4.3. Signal from the Subdivisions of the Chest 37 4.4. The Influence of the Surgical Technique on Signal Strength 38 5. Conclusion 39 6. Abstract 41 7. Zusammenfassung 42 8. References 44 9. Appendix 60 10. Acknowledgements 82 11. Resume 83 Anlage 184 Anlage 2 8

Predictors of weight regain after the end of 10-week dietary weight-loss programme (NUGENOB study)

I would like to thank my consultant, MUDr. Jan Polák for his constructive criticism over my work and his comments for improvements from which I learned much and they were all well appreciated I would like to thank Eva Nemcova, fellow student of the 3rd faculty of Medicine for providing me with the anthropologic data of this study I would like to thank the whole department of Sports Medicine, lead by Doc. MUDr. Vladimír Štich, PhD. for providing me with the resources without which this thesis could not have been mad