A wavelet-based VCG QRS loop boundaries and isoelectric coordinates detector

This paper deals with a wavelet-based algorithm for automatic detection of isoelectric coordinates of individual QRS loops of VCG record. Fiducial time instants of QRS peak, QRS onset, QRS end, and isoelectric PQ interval are evaluated on three VCG leads (X, Y, Z) together with global QRS boundaries of a record to spatiotemporal QRS loops alignment. The algorithm was developed and optimized on 161 VCG records of PTB diagnostic database of healthy control subjects (HC), patients with myocardial infarction (MI) and patients with bundle branch block (BBB) and validated on CSE multilead measurement database of 124 records of the same diagnostic groups. The QRS peak was evaluated correctly for all of 1,467 beats. QRS onset, QRS end were detected with standard deviation of 5,5 ms and 7,8 ms respectively from the referee annotation. The isoelectric 20 ms length PQ interval window was detected correctly between the P end and QRS onset for all the cases. The proposed algorithm complies the (2 sigma(CSE)) limits for the QRS onset and QRS end detection and provides comparable or better results to other well-known algorithms. The algorithm evaluates well a wide QRS based on automated wavelet scale switching. The designed multi-lead approach QRS loop detector accomplishes diagnostic VCG processing, aligned QRS loops imaging and it is suitable for beat-to-beat variability assessment and further automatic VCG classification.Web of Science13art. no. 94182

Determination of reference intervals in small size dogs for variables used in veterinary cardiology

La dégénérescence valvulaire mitrale (MVD) est la cardiopathie la plus fréquente chez le chien de petit format. Certaines variables écho-Doppler et sanguines sont incontournables dans son évaluation mais nécessitent d'être interprétées selon un intervalle de référence (IR) spécifique. L'objectif de ce travail a été de déterminer des IR pour 31 variables d'utilité clinique en cardiologie vétérinaire dans une population importante de chiens sains de petit format et selon les recommandations du Clinical and Laboratory Standard Institute. Les trois études réalisées permettent de conclure que l'élaboration d'IR spécifiques dans une sous-population canine est pertinente pour certaines variables. De plus, l'effet de certains facteurs comme le poids, l'âge et le sexe doivent être pris en compte si un intérêt clinique est identifié.Degenerative mitral valve disease is the most common heart disease in small size dogs. Several echocardiographic, Doppler and blood variables are crucial in the assessment of the disease but need to be interpreted in the light of a specific reference interval (RI). The aim of this work was to determine RI for 31 variables of clinical interest in veterinary cardiology within a large population of healthy small size dogs by using the Clinical and Laboratory Standard Institute recommendations. The three studies performed here allowed to conclude that determination of specific RI in this canine sub-population is relevant. Moreover, the effect of covariates such as body-weight, age and gender should be taken into account only if a clinical interest is identified

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 142

This bibliography lists 256 reports, articles, and other documents introduced into the NASA scientific and technical information system in May 1975 for aerospace medicine and biology

Acute Effects of Exercise Mode on Arterial Stiffness and Cardiac Autonomic Function in Healthy Young Adults

Purpose: To analyse the time-course of post-exercise cardiovagal modulation and local and regional changes on indices of arterial stiffness (AS) to three group fitness classes (GFC), in healthy young adults. Methods: 12 participants attended separated sessions of either BIKE, Pump Power (PUMP), Global Training (GT), or no exercise. In each session, participants initially undertook a supine rest followed by one of the sessions in a randomized order. Testing after each session took place at 10-, 20-, and 30-min, including assessments of regional and local indices of AS, cardiovagal modulation and baroreflex sensitivity (BRS). Results: No post-exercise changes were found in aortic and upper-limb pulse wave velocity (PWV). Local carotid indices remained unchanged following GT but increased immediately following (10-min) BIKE and PUMP. Lower-limb PWV, Ln-RMSSD, Ln-HF, BRS and BEI were immediately decreased following the three group fitness classes. Conclusions: These findings suggest that 1) exercise modality influences indices of local AS while having no effect on the remaining assessments, and 2) evidence derived from laboratorial experiments on the acute effects of exercise on indices of arterial stiffness seem to have ecological validity, but this may not be the case for cardiovagal modulation and BRS responses.Objetivo: Analisar a evolução temporal da modulação cardiovagal pós-exercício e as mudanças locais e regionais nos índices de rigidez arterial (RA), após 3 aulas de grupo, em jovens adultos saudáveis. Métodos: 12 participantes realizaram sessões de BIKE, Pump Power (PUMP), Global Training (GT) ou nenhum exercício. Em cada sessão, os participantes permaneceram em repouso seguido por uma das sessões. As avaliações após cada sessão ocorreram aos 10, 20 e 30 minutos, incluindo avaliações regionais e locais de RA, modulação cardiovagal e sensibilidade barorreflexa (SBR). Resultados: Não foram encontradas quaisquer alterações pós-exercicio na velocidade de onda de pulso (VOP) da aorta e dos membros superiores. Índices de RA local permaneceram inalterados após GT, porém aumentaram imediatamente após (10-min) BIKE e PUMP. A VOP dos membros-inferiores, Ln-RMSSD, Ln-HF, SBR e BEI diminuíram imediatamente após as três aulas de grupo. Conclusões: Estes resultados sugerem que 1) a modalidade de exercício influencia os índices de RA local, não tendo qualquer efeito nas restantes avaliações, e 2) estudos realizados em contexto laboratorial sobre efeitos agudos do exercício nos índices de rigidez arterial parecem ter validade ecológica, mas este não parece ser o caso para a modulação cardiovagal e SBR

The Effects of Boron on the Range of Motion of Dexterity Related Joints: A Patient with Rheumatoid Arthritis

Rheumatoid arthritis is a progressive, destructive and chronic, inflammatory disease of the joint synovium. Signs and symptoms include pain, limited range of motion, swelling, and tenderness, which may progress to deformity. These manifestations may limit dexterity, independent living, and the overall well being of an individual. Living with daily restrictions proves to be a psychologically distressing experience. An increase in the dietary boron level of laboratory rats has shown to have a positive effect on the range of motion in their involved joints. This concept was tested on a human subject at the United States Department of Agriculture\u27s Human Nutrition Research Center in Grand Forks, North Dakota over a six-month period from January 9th to June 19th, 2001. Joint involvement was assessed using goniometric measurements, a Poly Arthritis form, along with palpation of 16 fibromyalgic points. Subjective information was compiled regarding subject\u27s level of pain, stiffness, bogginess, and soreness. The subject was measured on a consistent day and time each week. The study was conducted under the direction of Dr. Curtiss Hunt at the Human Nutrition Research Center and Beverly Johnson PT, MS at the University of North Dakota Department of Physical Therapy. Institutional Review Board approval was obtained, and inter-rater and intra-rater reliability were established prior to testing. A standardized verbal instruction regimen, to guide the subject and to encourage her to give her maximal effort during measurements, was used. With an increased intake of boron, a significant influence on the range of motion was predicted. It was found, however, the active number of joints for this subject remained relatively constant, proving bogginess and soreness/sensitivity to palpation to still be present. However, the subjective rating of pain, fibromyalgic points, and hours of morning stiffness decreased with boron deprivation. By analyzing the range of motion statistics, 21 out of 64 tested motions were found to display changes in the measurements of dexterity-related joints for an individual with rheumatoid arthritis between boron supplementation and deprivation. A general increase was noted with boron supplementation, whereas a decrease was noted in the range of motion with boron deprivation. The purpose of this case report was to analyze the effect of boron supplementation and deprivation and to aid in improving the pathological related signs and symptoms of an individual with rheumatoid arthritis. The potential to decrease the clinical manifestations and reduce the psychological stress of living with a chronic illness would benefit individuals with rheumatoid arthritis

Autonomic control in preterm infants - what we can learn from mathematical descriptions of vital signs

Background: Preterm birth is a major burden, affecting approximately 15 million infants each year. Recent advances in reproductive medicine increases that number even more. The population of preterm infants in particular suffers from autonomic dysregulation that manifests as temperature instability and poor control of heart rate and breathing. Thermal care, monitoring of vital signs in a neonatal intensive care unit, pharmacotherapy, and respiratory support over weeks to months is necessary. Improvements in neonatal care in the past years lead to a decrease in mortality, especially in very preterm infants. However, former preterm infants still are a high-risk population for acute and chronic sequelae as a result of the interruption of the physiological development. A better understanding of the pathophysiology of the autonomic dysregulation in that population would be very useful. Unfortunately, accurate diagnostic tools that objectively assess and quantify the immature autonomic control in neonates are lacking. Methods: In this PhD thesis we examined different effects of the immature autonomic control in very preterm infants under clinically relevant conditions. We conducted a prospective single center observational study, where we assessed fluctuations in body temperature, sleep behavior, and heart rate variability in very preterm infants. We described the different regulatory systems using distinct mathematical expressions, such as detrended fluctuation analysis and sample entropy. We assessed associations between these outcome parameters and relevant factors of the infant’s history, such as demographic parameters and co-morbidities. Besides that, we analyzed lung function measurements of preterm infants and healthy term controls at a comparable postconceptional age, to describe respiratory control. Results: This study is systematically assessing different physiological signals of autonomic dysregulation in preterm infants during their first days of life. We found associations between parameters describing the complexity of time series analysis and maturity or relevant co-morbidities of the infants. In the analysis of heart rate variability we even found that parameters derived from time series analysis, assessed during the infants first days of life, improve our ability to predict future evolution of the infants’ autonomic stability. Lastly, several weeks after the expected due date, tidal breathing pattern of preterm infants showed a different reaction in response to a sigh when compared to term born controls at equivalent postmenstrual age indicating that autonomic dysregulation in preterm infants is still present well beyond the expected due date. Conclusion: A better understanding about the resolution of autonomic dysregulation in this population is not only important for the infant and its family but has the potential to support resource allocation and identification of patients with elevated risk for future deterioration. We thus think that the insights about the immature autonomic control in preterm infants, gained through this PhD work, are of substantial scientific and clinical relevance

The common fatty acids of human depot fat

The current renaissance in biological research has evoked widespread interest in the field of lipid metabolism. While extensive studies during the past decade have greatly expanded our knowledge of the subject, these researches have been directed primarily to the serum lipids. By far the greatest accumulation of lipid in the mammalian organism is found in the depot fat. This tissue had, until fairly recently, been generally regarded as a semi-static food store, expanding and shrinking in response to a relative excess or deficit of dietary calories. This simple concept is no longer tenable. The pioneering work of a few workers in the field during the past few decades has more recently interested many others and the accumulated evidence has established the fat depot among the more active organs in the mamnalian organism

Observations on the Coronary Arteries

Abstract Not Provided