Reaction Kinetics Modeling of eHsp70 Induced by Norepinephrine in Response to Exercise Stress.

Exercise elicits a systemic adaptation reaction, involving both neuroendocrine and cellular/paracrine stress responses, exemplified by the sympathoadrenergic activity and the release of cellular Hsp70 into the circulation. Regular sports training is known to result in increased fitness. In this study, we characterized the plasma norepinephrine and Hsp70 levels and modeled their relationship in response to exercise stress by bicycle ergometer in 12 trained judoka athletes and in 10 healthy controls. Resting norepinephrine was similar in both groups, whereas Hsp70 was significantly higher in controls compared to athletes. Intense exercise load induced both norepinephrine and Hsp70 elevation. However, both norepinephrine and Hsp70 were significantly lower in athletes compared to the control group. A reaction kinetic model was developed that provided a quantitative description of norepinephrine-facilitated extracellular Hsp70 release, congruent with the experimental data. Our study indicates that exercise-induced norepinephrine and extracellular Hsp70 may be coordinated responses to physiological stress, which are robustly affected by regular sports activity.

The effects of changing meteorological parameters on fatal aortic catastrophes.

BACKGROUND: Over the span of the last decade, medical research has been increasingly putting greater emphasis on the study of meteorological parameters due to their connection to cardiovascular diseases. The main goal of this study was to explore the relationship between fatal aortic catastrophes and changes in atmospheric pressure and temperature. METHODS: We used a Cox process model to quantify the effects of environmental factors on sudden deaths resulting from aortic catastrophes. We used transfer entropy to draw conclusion about the causal connection between mortality and meteorological parameters. Our main tool was a computer program which we developed earlier in order to evaluate the relationship between pulmonary embolism mortality and weather on data sets comprised of aortic aneurysm (AA) and acute aortic dissection (AAD) cases, where one of these two medical conditions had led to fatal rupture of the aorta. Our source for these cases were the autopsy databases of Semmelweis University, from the time period of 1994 to 2014. We have examined 160 aneurysm and 130 dissection cases in relation to changes in meteorological parameters. The algorythm implemented in our program is based on a non-parametric a Cox process model. It is capable of splitting slowly varying unknown global trends from fluctuations potentially caused by weather. Furthermore, it allows us to explore complex non-linear interactions between meteorological parameters and mortality. RESULTS: Model measures the relative growth of the expected number of events on the nth day caused by the deviation of environmental parameters from its mean value. The connection between ruptured aortic aneurysms (rAA) and changes in atmospheric pressure is more significant than their connection with mean daily temperatures. With an increase in atmospheric pressure, the rate of rAA mortality also increased. The effects of meteorological parameters were weaker for deaths resulting from acute aortic dissections (AAD), although low mean daily temperatures increased the intensity of occurrence for AAD-related deaths. CONCLUSION: The occurrence rate of fatal aortic catastrophes showed a slight dependence on the two examined parameters within our groups.

[The effect of alternating meteorological parameters on fatally ruptured aortic aneurysms (autopsy-based data)]. / Meteorológiai paraméterek változásának hatása a halálos kimenetelu aortaaneurysma-rupturákra.

INTRODUCTION: There are several statements about the connection between cardiovascular diseases and climate change. On behalf of our observation-based knowledge we hypothesized a relationship between the occurence of aortic aneurysm (AA) rupture and weather changes. AIM: The purpose of our study was to explore the relationship between fatal aortic catastrophe and changes in atmospheric pressure and temperature. By using a new method we could even measure the intensity of the connection. METHOD: We have developed a software earlier to examine the link between pulmonary embolism mortality and the weather on data sets comprised of aortic aneurysm cases, where the medical condition had led to the fatal rupture of the aorta. For the events mentioned earlier we used the autopsy database of Semmelweis University between January 1, 2005 and January 1, 2014. Altogether we examined 152 aneurysm-related aortic catastrophes. We reported the exact day of the incident and the weather conditions on that day and the day before. RESULTS AND CONCLUSION: We have defined that the occurrence rate of fatal aortic catastrophe showed a slight dependence on the two examined parameters within our groups. We have found the connection related to ruptured aortic aneurysm and changes in atmospheric pressure more significant than their connection with mean daily temperatures. With the increase in atmospheric pressure, the rate of AA mortality also increased. In the knowledge of our results we believe that the mathematical model we used can be an effective starting point for population-based and prospective studies. Orv Hetil. 2018; 159(37): 1501-1505.

Evaluation of meteorological and epidemiological characteristics of fatal pulmonary embolism.

The objective of the present study was to identify risk factors among epidemiological factors and meteorological conditions in connection with fatal pulmonary embolism. Information was collected from forensic autopsy records in sudden unexpected death cases where pulmonary embolism was the exact cause of death between 2001 and 2010 in Budapest. Meteorological parameters were detected during the investigated period. Gender, age, manner of death, cause of death, place of death, post-mortem pathomorphological changes and daily meteorological conditions (i.e. daily mean temperature and atmospheric pressure) were examined. We detected that the number of registered pulmonary embolism (No 467, 211 male) follows power law in time regardless of the manner of death. We first described that the number of registered fatal pulmonary embolism up to the nth day can be expressed as Y(n) = α ⋅ n (ß) where Y denotes the number of fatal pulmonary embolisms up to the nth day and α > 0 and ß > 1 are model parameters. We found that there is a definite link between the cold temperature and the increasing incidence of fatal pulmonary embolism. Cold temperature and the change of air pressure appear to be predisposing factors for fatal pulmonary embolism. Meteorological parameters should have provided additional information about the predisposing factors of thromboembolism.

Non-invasive in vivo time-dependent strain measurement method in human abdominal aortic aneurysms: Towards a novel approach to rupture risk estimation.

We aim to introduce a novel, inverse method for in vivo material parameter identification of human abdominal aortic aneurysms (AAA), which could overcome one of the greatest sources of uncertainty in patient-specific simulations, and could also serve as a rapid, patient-calibrated, novel measure of aneurysm rupture risk. As an initial step, the determination of the kinematic fields is presented here. Images of the AAA lumen, acquired in 10 discrete time-steps through a stabilized cardiac cycle by electrocardiogram-gated computer tomography angiography, are used to approximate the in vivo, time dependent kinematic fields of the arterial wall using a novel, incompressible Kirchhoff-Love shell element implemented into the isogeometric analysis framework. Defining a smoothing parametric surface via 2D bicubic spline fitting in the spatial, and by harmonic regression in the temporal domain, we are able to adequately mitigate the measurement inaccuracy. The ill-posedness of the problem requires certain assumptions on the displacement. In our case, based on numerical fluid structure interaction simulation observations, we hypothesized the incremental displacement vector of the reference surface to coincide with its corrected normal; hence the periodic movement was assured. Finally, we present two examples: an AAA and an undilated calcificated aorta. Strains in the diseased part were compared to those in a healthy arterial section of the same patient and found to have significant differences in both specimens. In the case of AAAs, high spatial gradients surrounding the dilated part indicate abrupt changes in material properties, a phenomenon less significant for the atherosclerotic case.