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This is the peer reviewed version of the following article: Brønd, J. C., Aadland, E., Andersen, L. B., Resaland, G. K., Andersen, S. A. & Arvidsson, D. (2019). The ActiGraph counts processing and the assessment of vigorous activity. Clinical Physiology and Functional Imaging, 39(4), 276-283, which has been published in final form at https://doi.org/10.1111/cpf.12571. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions The purpose of this study was to investigate the effect of different band‐pass filters on the measurement bias with ActiGraph counts during high speed running and for estimating free‐living vigorous physical activity (VPA). Two alternative band‐pass filters were designed, extending the original frequency range from 0·29 to 1·66 Hz (AG) to 0·29–4 Hz (AC4) and 0·29–10 Hz (AC10). Sixty‐two subjects in three age groups participated in a structured locomotion protocol consisting of multiple walking and running speeds. The time spent in free‐living VPA using the three different band‐pass filters were evaluated in 1121 children. Band‐pass filter specific intensity cut‐points from both linear regression and ROC analysis was identified from a calibration experiment using indirect calorimetry. The ActiGraph GT3X+ device recording raw acceleration at 30 Hz was used in all experiments. The linear association between counts and running speed was negative for AG but positive for AC4 and AC10 across all age groups. The time spent in free‐living VPA was similar for all band‐pass filters. Considering higher frequency information in the generation of ActiGraph counts with a hip/waist worn device reduces the measurement bias with running above 10 km·h−1. However, additional developments are required to accurately capture all VPA, including intermittent activities.

BACKGROUND: Cardiac Rubidium-82 (82 Rb) positron emission tomography/computed tomography (PET/CT) provides a measure of the myocardial blood flow and the myocardial flow reserve, which reflects the function of both large epicardial arteries and the myocardial microcirculation. Knowledge on changes in the myocardial microvascular function over time is lacking.METHODS: In this cohort study, we recruited 60 persons with type 2 diabetes and 30 non-diabetic controls, in 2013; all free of overt cardiovascular disease. All underwent a cardiac 82 Rb PET/CT scan. In 2019, all survivors (n = 82) were invited for a repeated cardiac 82 Rb PET/CT scan using the same protocol, and 29 with type 2 diabetes and 19 controls participated.RESULTS: Median duration between visits was 6.2 years (IQR: 6.1-6.3). In the total cohort, the mean age was 66.4 years (SD: 9.3) and 33% were females. The myocardial flow reserve was lower in persons with type 2 diabetes compared to controls (p = 0.002) but there was no temporal change in the myocardial flow reserve in participants with type 2 diabetes: mean change: -0.22 (95% CI: -0.47 to 0.02) nor in controls: -0.12 (-0.49 to 0.25) or when comparing type 2 diabetes to controls: mean difference: -0.10 (95% CI: -0.52 to 0.31). The temporal reduction in stress-induced myocardial blood flow did not differ within the groups but was more pronounced in type 2 diabetes compared to controls: mean difference: -0.30 (95% CI: -0.55 to -0.04).CONCLUSION: The myocardial microvascular function was impaired in persons with type 2 diabetes compared to controls but did not change significantly in either of the groups when evaluated over 6 years.

Excess insulin secretion and hyperinsulinaemia contribute to the progression of type 2 diabetes. However, the mechanisms leading to insulin hypersecretion remain largely unknown. Based on our preliminary data, we examined whether triglycerides and very low-density lipoprotein (VLDL) are independently associated with insulin secretion, and whether ethnicity/race modulates these associations. Fasting triglycerides and VLDL were measured in a multiethnic cohort of 630 non-diabetic adolescents. Insulin secretion, β-cell function parameters, insulin sensitivity and insulin clearance were estimated through a 3-h oral glucose tolerance test. Metabolic assessments were repeated after 2 years in 239 subjects. Triglycerides and triglyceride-rich VLDL (large and medium size fractions) were associated with both basal and glucose-stimulated insulin secretion, after adjustment for age, sex, ethnicity, BMI z-score, plasma glucose, and insulin sensitivity. Ethnicity per se had an impact on lipid profile and β-cell function, but did not modulate the effect of triglycerides/VLDL on insulin secretion. At follow-up, changes in triglyceride levels were proportional to changes in insulin secretion. These findings support the hypothesis that hypertriglyceridaemia is an important stimulus for β-cell insulin release in young people under both fasting and fed conditions.

In mechanically ventilated, lung injured, patients without spontaneous breathing effort, atelectasis with shunt and desaturation may appear suddenly when ventilator pressures are decreased. It is not known how such a formation of atelectasis is related to transpulmonary pressure (PDynamic transverse computed tomography scans were acquired in ten anaesthetized, surfactant-depleted pigs with preserved spontaneous breathing, as ventilator support was lowered by sequentially reducing inspiratory pressure and positive end expiratory pressure in steps. The volumes of gas and atelectasis in the lungs were correlated with PGradual decrease in PWe found a proportional correlation between atelectasis and P

Background: Reference values for working capacity, blood pressure, heart rate, perceived exertion, etc. during bicycle exercise tests have been sought after for many years. This is because earlier commonly used reference values for physical work capacity have been either too low or too high when compared to the clinical experience of several Swedish departments of clinical physiology. The aim of the study was to compare two commonly used reference materials with normal outcomes from a clinical database. Methods: Data from a clinical database of standardized exercise tests in Kalmar, Sweden, between 2004 and 2012, and having been judged as normal, were divided into 5-year categories of 5-10 to 75-80 years of age covering people from 7 to 80 years of age. Results: Maximal working capacity (W-max), maximal heart rate, maximal systolic blood pressure and maximal perceived exertion are presented for each of the 15 age categories. Regression equations are also presented for each sex with age and height as independent predictors. Quantitative comparisons of W-max are calculated for the three materials and possible explanations discussed. Conclusions: Values of W-max lie between the two reference materials most commonly used in Sweden. In addition, the present material covers subjects aged 7-19 years.

The term ‘translational research’ was coined 20 years ago and has become a guiding influence in biomedical research. It refers to a process by which the findings of basic research are extended to the clinical research setting (bench to bedside) and then to clinical practice and eventually health policy (bedside to community). It is a dynamic, multidisciplinary research approach. The concept of translational physiology applies the translational research model to the physiological sciences. It differs from the traditional areas of integrative and clinical physiology by its broad investigative scope of basic research to community health. Translational physiology offers exciting opportunities, but presently is under-developed and -utilized. A key challenge will be to expand physiological research by extending investigations to communities of patients and healthy (or at risk) individuals. This will allow bidirectional physiological investigation throughout the translational continuum: basic research observations can be studied up to the population level, and mechanisms can be assessed by ‘reverse translation’ in clinical research settings and preclinical models based on initial observations made in populations. Examples of translational physiology questions, experimental approaches, roadblocks and strategies for promotion are discussed. Translational physiology provides a novel framework for physiology programs and an investigational platform for physiologists to study function from molecular events to public health. It holds promise for enhancing the completeness and societal impact of our work, while further solidifying the critical role of physiology in the biomedical research enterprise.

Department of Clinical Physiology and Nuclear Medicine, Bispebjerg Hospital, University of Copenhagen, Copenhagen, DenmarkCorresponding author: Jonas Bloch Thorlund, Institute of Sports Science and Clinical Biomechanics, University of SouthernDenmark, Campusvej 55, DK-5230 Odense M, Denmark. Tel: 145 6550 3894, Fax: 145 6550 3480, Email: jthorlund@health.sdu.dkAccepted for publication 16 March 2010The purpose of the present study was to determine thechanges in maximal muscle strength, rapid force capacity,jumping performance and muscle morphology following aSpecialForcesmilitaryoperationinvolving8daysofmuscleunloading. Nine male Special Forces soldiers were testedbefore (pre) and immediately after (post1) an 8-day simu-latedspecialsupportandreconnaissance(SSR)missionandafter 3h of active recovery (post2). Maximal musclestrength (MVC) and rate of force development (RFD)were measured along with maximal counter movementjump height (JH). Muscle biopsies were obtained from thevastus lateralis at pre and post1. Acute reductions werefound in MVC (11%), JH (10%) and RFD (17–22%) after8 days of muscle unloading (post1) (P 0.05). Type IIXfiber type area% increased (P 0.05) at post1 togetherwith a tendency toward increased type IIX fiber type %(P50.09) and decreased type I fiber type % (P50.06),suggesting a transition toward a less fatigue-resistant fiber-type profile. In conclusion, short-term unloading duringSSR missions led to marked reductions in mechanicalmuscle function and functional performance, which may bepartly explained by the changes in muscle morphology.Future studies should identify intervention strategies tocounter-act the observed impairments.

Hasselbalch H, JOrgensen F, Wamberg T, Hey H. (Department of Radiology, Glostrup Hospital, the Dispensary, Royal Veterinary and Agricultural University, Departments of Medicine B and Radiology, Frederiksberg Hospital, Copenhagen, and Department of Clinical Physiology, County Hospital, HillerOd, Denmark.) Alternatives to optimal administration of tablets. This controlled investigation of 27 volunteers compared the effect of cold and lukewarm tap water and carbonated water on the passage through the esophagus of a large circular tablet containing barium sulphate and of the same size and specific gravity as an acetylsali-cylic acid tablet (Kodimagnylss®). The influence of yoghurt on the passage of the same tablet was also examined. The investigation emphasized the importance of taking tablets together with 100 ml of liquid. A comparison of the transit times for tablets taken together with 100 ml of cold carbonated water and 100 ml of lukewarm tap water showed a significantly better passage when the tablets were taken with cold carbonated water (p=0.01). A similar advantage of carbonated liquids was seen when tablets were taken with 25 ml of lukewarm tap water as compared with 25 ml of cold carbonated water (p=0.01). Administration of a tablet in a tablespoon of yoghurt is a good alternative, even though the bioavailability of certain preparations may be reduced.

Although we have known that oxygen tension affects erythrocyte production since the 19th century, we have only recently begun to understand many subtleties of erythropoietin (EPO) physiology. EPO administration has allowed hundreds of thousands of patients to avoid transfusions. With the beneficial effects so apparent a detailed understanding of the full clinical physiology of this plasma factor seemed less important. However, the unanticipated increase in mortality found in recent randomized studies is prompting a reassessment of this view. We will review what is known about the physiology of this plasma factor that, it is now clear, is more than just an erythrocyte production factor.

This study reports a citation analysis of 217 scientific papers on clinical physiology and nuclear medicine published in 69 different journals during the years 1985-92. The actual citation frequency was compared with the journal 'impact factor' (i.e. the average number of times a paper is cited in a particular journal in the year of publication and the subsequent year). The average impact factor per paper was 1.96 and per journal 1.92 (range 0.0-22.8). A direct relation was found between the journal impact factor and the citation factor (i.e. the actual citations in the year of publication and the subsequent year) (journals with five or more papers R = 0.69, P < 0.01; all journals R = 0.40, P < 0.001). However, the citation factor was significantly below the journal impact factor (P < 0.0001). An almost linear relation was found between cumulated citations and time (R = 0.99, P < 0.02.-0.0001), but an initial phase of no citation was identified, and the number of citations per year reached a maximum or plateau 3-7 years after publication, which was later than the general maximum of 2-3 years for all medical specialities. In a sample of 200 known autocitations, 75% of the papers had full recovery, 3% mixed recovery and 22% no recovery, giving an overall recovery of 70%. In conclusion, although a phase of no citation was identified, which gave a lower citation factor than the journal impact factor, the citation frequency increased over time, and altogether there seems to be a good agreement between journal impact factor and overall citation frequency of papers on clinical physiology and nuclear medicine.

Summary. This study reports a bibliometric analysis of scientific publications emanating from departments of clinical physiology and nuclear medicine, Denmark, during the years 1989–1994. The total number of publications during this period was 860 (763 scientific journal papers, 71 book/book chapters and 26 theses). Whereas the number of publications per year (188–113) decreased significantly with time (r= -0.94, P < 0.02), the number of authors (mean 4·41) was almost constant over time. University/university-related departments accounted for 96% of the papers. Only 8% of the papers resulted from a collaboration between two or more departments of clinical physiology and nuclear medicine, but the collaboration with other medical specialities and institutions was much greater (85%). The 763 papers were published in 239 different scientific journals, 80% in journals with an official ‘impact factor,’ a bibliometric measure of quality (the average number of times a paper is cited in a journal in the publishing year and the subsequent year). Twenty per cent (20%) and 8.4% were printed in journals with an impact factor, respectively, of above 2.1 (the 500 journals most cited) and 3.7 (the 200 most cited), which is significantly above the national average (16.6% and 6.0%, P < 0.001). The ‘cumulated impact’ (i.e. the impact of all papers) showed a borderline significant decrease over time (r= -0.77, P= 0.1), whereas the average impact per paper (1.53) remained almost constant and was significantly above the national average (1.10, P < 0.001). A close relationship was found between the number of papers from a department and its cumulated impact (r= -0.97, P < 0–001). It is concluded that the total number of scientific papers from Danish departments of clinical physiology and nuclear medicine fell in the period, whereas the volume of quality, as assessed on the cumulated impact, only fell with borderline significance, and the impact per paper was almost constant from 1989 to 1994, and was above the national average.

Clinical physiology is a branch of physiology particularly dealing with functional disturbances in disease (pathophysiology) and the integrated function of the human body in disease against the background of normal function in healthy subjects, suitable physiological methods for the study of patients--particularly for diagnostic purposes--as well as for research, and the education of medical students and laboratory assistants in these fields. Departments of clinical physiology in university hospitals form a bridge between basic physiology and many clinical specialties. Independent departments of clinical physiology developed early in Sweden due to the work of Professor Torgny Sjöstrand at the Karolinska Hospital in Stockholm, and have been models of research, teaching and hospital organization which have been followed in several other countries. The International Union of Physiological Sciences (IUPS) has recognized clinical physiology as a separate branch of physiology by approving a Commission of Clinical Physiology which has contributed to the programme of this and, we hope, future congresses, as well as promote the development of clinical physiology internationally.

Lange P, Groth, S, Nyboe J, Appleyard M, Mortensen J, Jensen G, Schnohr P (Copenhagen City Heart Study, Medical Department B and Department of Clinical Physiology and Nuclear Medicine KF, Rigshospitalet, and Medical Department P, Bispebjerg Hospital, Copenhagen, Denmark). Chronic obstructive lung disease in Copenhagen: cross-sectional epidemiological aspects. We analysed data from the Copenhagen City Heart Study to study the prevalence, possible risk factors for, and inter-relations between bronchial hypersecretion (BH) and chronic airflow limitation. The study sample consisted of 12698 subjects between 20 years and 90 years of age, randomly selected from the population of the city of Copenhagen. The age-adjusted overall prevalence of BH in the population of Copenhagen was estimated to be 10.1%; 12.5% in men and 8.2% in women. The overall prevalence of clinically relevant chronic airflow limitation (forced expiratory volume in 1 s < 60% of that predicted) was 3.7% and not significantly different between sexes. Both airflow limitation and BH increased with age, smoking, alcohol consumption, short education, and low income. However, the association of airflow limitation with alcohol consumption, education and income was much weaker than the association with smoking. Regardless of smoking habits, the majority of subjects with airflow limitation did not report symptoms of bronchial hypersecretion.

Krabbe, S., Christiansen, C., Rodbro, P and Transbol, I. (University Clinic of Paediatrics, Children's Hospital Fuglebakken, Copenhagen F, Department of Clinical Chemistry, Glostrup Hospital, Glostrup, Department of Clinical Physiology Aalborg Sygehus Syd, Aalborg, and Division of Endocrinology, Department of Internal Medicine, Hvidovre Hospital, University Hospital of Copenhagen, Hvidovre, Denmark). Pubertal growth as reflected by stimultaneous changes in bone mineral content and serum alkaline phosphatase. Acta Paediatr Scand, 69:49, 1980.—Bone mineral content and total serum alkaline phosphatase were measured simultaneously in 230 normal children and adolescents aged 7–20 years. The bone mineral content showed almost no variation from the age of 7 to 13 in boys and 7 to 11 in girls. Thereafter a sharp increase was seen in both sexes with a highly significant sex difference between the mean values. Bone mineral content showed a fairly high correlation with age, height, weight, and surface area in boys. Before the time of the growth spurt, however, these variables were poorly correlated or not correlated at all. Concentrations of total serum alkaline phosphatase increased up to the age of 14 in boys and 11 in girls. Thereafter a rapid fall was seen in both sexes, the mean levels being significantly higher in boys. The fall approximated adult levels in boys by the age of 20 and in girls by 18. A significant negative correlation between bone mineral content and serum alkaline phosphatase was seen both in boys (r= 0.71, p < 0.001) and in girls (r= 0.79, p < 0.001)

Furberg, C. and Hornell, H. (Department of Clinical Physiology and Paediatrics, Central Hospital, Boden, Sweden). Familial QT prolongation and risk of sudden death. Acta Paediatr Scand, 64:777, 1975.–Two sisters with the syndrome of familial QT prolongation in the ECG and syncope are presented. A recently suggested mechanism of the syndrome is presented and preventive measures to reduce the risk of sudden death associated with it are proposed.