Effect of endurance training and seasonal fluctuation on coagulation and fibrinolysis in young sedentary men

Van den Burg, P. J. M., J. E. H. Hospers, M. Van Vliet, W. L. Mosterd, B. N. Bouma, and I. A. Huisveld. Effect of endurance training and seasonal fluctuation on coagulation and fibrinolysis inyoung sedentary men. J. Appl. Physiol.82(2): 613-620, 1997.The effect of 12 wk of submaximal trainingon hemostatic variables was studied in 20 young sedentary men (Tr) and19 nontraining matched controls (Con). After training, a morepronounced increase in factor VIII coagulant activity(P < 0.01), reflected in a decrease in activated partial thromboplastin time(P < 0.01) during maximal exercise,was seen. Both basal plasminogen activator inhibitor 1 antigen (PAI-1Ag) and activity (PAI-1 Act; P < 0.05), as well as basal and exercise-induced tissue-type plasminogenactivator antigen (t-PA Ag; P < 0.05), were decreased after training. The overall effect onfibrinolysis was reflected in an increase in the t-PA Act/t-PA Ag ratioin the Tr group. In contrast, during the same period (February-June),the Con group demonstrated an increase in basal PAI-1 Ag and PAI-1 Act(P < 0.05), together with anincrease in basal and exercise-induced t-PA Ag(P < 0.05). Both basal andexercise-induced t-PA Act were unchanged, but t-PA Act/t-PA Ag wasdecreased (P < 0.05) in the Congroup. We conclude that physical training promotes both coagulation andfibrinolytic potential during exercise and may reverse unfavorableseasonal effects on fibrinolysis.

     

An unusual case of cardiomyopathy in a 75-year-old woman

In this report we describe a 75-year-old woman who presented with an acute coronary syndrome and transient catecholamine-induced cardiomyopathy with severe pulmonary oedema necessitating mechanical ventilation. During mechanical ventilation several episodes of hypertension occurred despite severe left ventricular systolic dysfunction. A pheochromocytoma was diagnosed and after successful surgical resection the patient''s condition improved. Three months after surgery myocardial scintigraphic examination demonstrated a normal ejection fraction and no signs of adenosine-induced ischaemia.     

Pre-participation screening of asymptomatic athletes

Catastrophic events, be it traffic accidents, natural disasters or homicides, always lead to scrutiny. Could we have seen the event coming and could it have been prevented? In the case of a sudden cardiac arrest of a seemingly healthy athlete the public outcry is not any different. Despite an intrinsic appeal for screening to prevent similar events, there is no evidence that justifies routine cardiovascular pre-participation screening of athletes. On balance, cardiovascular screening in athletes will most likely do more harm than good. Fatal exercise-related cardiac arrests do not occur very often. The true diagnostic yield of the pre-participation evaluation is not known and once a cardiac condition has been identified, the most appropriate intervention is often unclear. It follows that pre-participation screening of large groups of athletes without known cardiac disease will inevitably result in many false positive findings, while at the same time providing a false sense of security to those screened negative. Except for compelling reasons (e.?g. cascade screening, research settings, professional athletes), physicians should not engage in routine examination of asymptomatic athletes to prevent cardiac events.     

No psychological distress in sportsmen aged 45 years and older after cardiovascular screening,including cardiac CT: The Measuring Athlete’s Risk of Cardiovascular events (MARC) study

Background

Psychological distress caused by cardiovascular pre-participation screening (PPS) may be a reason not to implement a PPS program. We assessed the psychological impact of PPS, including cardiac computed tomography (CT), in 318 asymptomatic sportsmen aged ≥45 years.

Methods

Coronary artery disease (CAD) was defined as a coronary artery calcium score ≥100 Agatson units and/or ≥50% luminal stenosis on contrast-enhanced cardiac CT. Psychological impact was measured with the Impact of Event Scale (IES) (seven items) on a six-point scale (grade 0–5). A sum score ≥19 indicates clinically relevant psychological distress. A Likert scale was used to assess overall experiences and impact on sports and lifestyle.

Results

A total of 275 participants (86.5% response rate, 95% CI 83–90%) with a mean age of 54.5 ± 6.4 years completed the questionnaires, 48 (17.5%, 95% CI 13–22%) of whom had CAD. The median IES score was 1 (IQR 0–2, [0–23]). IES was slightly higher in those with CAD (mean rank 175 vs. 130, p < 0.001). One participant (with CAD) experienced clinically relevant psychological distress (IES = 23). Participants reported numerous benefits, including feeling safer exercising (58.6%, 95% CI 53–65%) and positive lifestyle changes, especially in those with CAD (17.2 vs. 52.1%, p < 0.001). The majority were satisfied with their participation (93.8%, 95% CI 91–97%).

Conclusion

Cardiovascular PPS, including cardiac CT, causes no relevant psychological distress in older sportsmen. Psychological distress should not be a reason to forego screening in sportsmen.

     

Plasma extracellular vesicle protein content for diagnosis and prognosis of global cardiovascular disease

Cardiovascular disease is a major public health problem worldwide. Its growing burden is particularly ominous in Asia, due to increasing rates of major risk factors such as diabetes, obesity and smoking. There is an urgent need for early identification and treatment of individuals at risk of adverse cardiovascular events. Plasma extracellular vesicle proteins are novel biomarkers that have been shown to be useful in the diagnosis, risk stratification and prognostication of patients with cardiovascular disease. Ongoing parallel biobank initiatives in European (the Netherlands) and Asian (Singapore) populations offer a unique opportunity to validate these biomarkers in diverse ethnic groups.     

Targeting residual inflammatory risk in coronary disease: to catch a monkey by its tail

Patients with coronary disease remain at high risk for future cardiovascular events, even with optimal risk factor modification, lipid-lowering drugs and antithrombotic regimens. A myriad of inflammatory pathways contribute to progression of the atherosclerotic burden in these patients. Only in the last few years has the inflammatory biology of atherosclerosis translated into clinical therapeutic options. Low-dose colchicine can provide a clinically relevant reduction in the risk for composite and individual major cardiovascular outcomes in patients with acute and chronic coronary syndromes. Among others, its anti-inflammatory effects in atherosclerosis seem to be related to neutrophil recruitment and adhesion, inflammasome inhibition, and morphological changes in platelets and platelet aggregation. Future research is aimed at further elucidating its particular mechanism of action, as well as identifying patients with the highest expected benefit and evaluating efficacy in other vascular beds. These data will help to formulate the role of colchicine and other anti-inflammatory drugs in patients with coronary disease and atherosclerosis in general in the near future.     

Sodium-glucose cotransporter 2 inhibitors: a practical guide for the Dutch cardiologist based on real-world experience

Sodium-glucose cotransporter 2 (SGLT2) inhibitors include a relatively new class of glucose-lowering drugs that reduce plasma glucose concentrations by inhibiting proximal tubular reabsorption of glucose in the kidney, while increasing its excretion in urine. Recent large randomised controlled trials have demonstrated that many of these agents reduce the occurrence of major adverse cardiovascular events, hospitalisation for heart failure, cardiovascular death and/or chronic kidney disease progression in patients with and without type 2 diabetes mellitus (DM2). Given their unique insulin-independent mode of action and favourable efficacy and adverse-event profile, SGLT2 inhibitors are promising and they offer an interesting therapeutic approach for the cardiologist to incorporate into routine practice. However, despite accumulating data supporting this class of therapy, cardiologists infrequently prescribe SGLT2 inhibitors, potentially due to a lack of familiarity with their use and the reticence to change DM medication. Here, we provide an up-to-date practical guide highlighting important elements of treatment initiation based on real-world evidence and expert opinion. We describe how to change DM medication, including insulin dosing when appropriate, and how to anticipate any adverse events based on real-world experience in patients with DM2 in the Meander Medical Centre in Amersfoort, the Netherlands. This includes a simple algorithm showing how to initiate SGLT2 inhibitor treatment safely, while considering the consequence of the glucosuric effects of these inhibitors for the individual patient.Supplementary InformationThe online version of this article (10.1007/s12471-021-01580-9) contains supplementary material, which is available to authorized users.     

Thermodynamic and kinetic parameters of lipase-catalyzed ester hydrolysis in biphasic systems with varying organic solvents

Kinetics of lipase-catalyzed hydrolysis of esters were modeled using reactant activities for aqueous-organic, biphasic systems. By using thermodynamic activities of the substrates in ordinary rate equations, the kinetic parameters were corrected for the contribution of substrate-solvent interactions and a uniform quantification of the substrates for lipase attached to the interface can be achieved. The kinetic parameters, on the basis of their thermodynamic activities, should be constant in different systems, provided that the solvents do not interfere with the binding of the substrates to the enzyme nor affect the catalytic mechanism. Experimental and computational methods on how to obtain the thermodynamic activities of the substrates are presented. Initial rates were determined for Pseudomonas cepacia lipase (PcL)-catalyzed hydrolysis of decyl chloroacetate in dynamic emulsions with various solvents. The thermodynamic equilibrium and corrected kinetic constants for this reaction appeared to be similar in various systems. The kinetics of PcL in an isooctane-aqueous biphasic system could be adequately described with the rate equation for a ping-pong mechanism. The observed inhibitory effect of decanol appeared to be a consequence of this mechanism, allowing the backreaction of the decanol with the chloroacetyl-enzyme complex. The kinetic performance of PcL in systems with toluene, dibutyl ether, and methyl isobutyl ketone could be less well described. The possible causes for this and for the remaining differences in corrected kinetic parameters are discussed. (c) 1995 John Wiley & Sons, Inc.     

Reductive activation of the methyl-tetrahydromethanopterin: coenzyme M methyltransferase from Methanobacterium thermoautotrophicum strain ΔH

The enzymatic conversion of formaldehyde to CH₃S-CoM in crude extracts of Methanobacterium thermoautotrophicum was used as a means to investigate the methyl-tetrahydromethanopterin: HS-CoM methyltransferase reaction. All components necessary for formaldehyde conversion were shown to be present in a soluble protein fraction. This soluble cell fraction still contained a major amount of corrinoids. Apart from tetrahydromethanopterin no other soluble cofactors were required for formaldehyde conversion. The dependence of the system on catalytic amounts of ATP was shown to be specific. Several nucleoside triphosphates or ADP were unable to substitute for ATP. Remarkably, various strong reducing systems, especially titanium(III)citrate could replace ATP to a large extent. The ATP-dependent formaldehyde conversion to CH₃S-CoM was inhibited in the presence of nitrous oxide, detergents or 2,3-dialdehyde-ATP. The results support a role for a corrinoid protein in the methyl-tetrahydromethanopterin: HS-CoM methyltransferase reaction at which ATP is involved in the activation of this protein, probably in the conversion of inactive B_12a or B_12r to active B_12s.Abbreviations HS-CoM Coenzyme M, 2-mercaptoethanesulfonate - CH₃S-CoM methylcoenzyme M, 2-(methylthio)ethanesulfonate - H₄MPT 5,6,7,8-tetrahydromethanopterin - BES 2-bromoethanesulfonate - BCE boiled cell-free extract - DTT dithiothreitol - TCS 3,3,4,5-tetrachlorosalicylanilide - DNTB 2,2-dinitro-5,5-dithiobenzoic acid - TES N-tris(hydroxymethyl)methyl-2-aminoethanesulfonate - HEPES N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid - PIPES piperazine-N,N-bis[2-ethanesulfonic acid] - AMP-PNP 5-adenylyl imidophosphate     

The first 20 years of bradypacing in the Netherlands - with special reference to organisational structures

In 1958, Arne Larson was the first patient to undergo an implantation of a completely internal pacemaker. Four years after this successful implantation by Senning and Elmquist in Sweden, Brom implanted the first internal system in a Dutch patient in Leiden. The pioneering work and the early history of bradypacing in the Netherlands until 1982 are described. This article covers the involvement of different specialists, organisations and some of the technical problems encountered during the rapid increase in the number of implantations and the establishment of specialist centres. The important role of Thalen and Rodrigo, as founding fathers of cardiac pacing in the Netherlands, is also highlighted. (Neth Heart J 2008;16(Suppl 1):S5-S8).