Search

The proper evaluation of whether our given bodily capabilities and environmental properties allow particular actions is indispensable for pertinent decisions, so-called affordance judgments. These can be impacted by older age or brain damage. Virtual Environments (VEs) may provide an efficient opportunity to offer trainings. But do people make affordance judgments in VEs in the same way that they do in Physical Environments (PEs)? And are these decisions trainable by use of VEs? We investigated 24 healthy young adults’ judgment performance of whether or not they could fit their hand into a given aperture. They were presented with a set of opening-increments and indicated their judgments by pressing a yes- or no-button. The stimuli were presented in PE using an aperture apparatus and in VE displayed by use of Oculus Rift goggles. Our results demonstrated the level of equivalence to be specific to the variable: While we found equivalence between VE and PE for the accuracy parameter, results were uncertain or non-equivalent for perceptual sensitivity and for judgment tendency, respectively. When applying training in VE, judgment accuracy improved significantly when tested subsequently within VE. Improvement appeared detectable in PE only on a descriptive level. Furthermore, equivalence testing post-training revealed that perceptual sensitivity performance in VE approached a PE-level. Promisingly, the VE training approach appeared applicable and efficacious within the VE. Future studies need to specify factors that enhance equivalence for detection theory variables and that facilitate transfer from VEs to PEs when judging action opportunities.

While the effects of an antenatal dietary intervention for women with obesity or overweight on pregnancy and newborn health have been extensively studied, the longer-term effects into childhood are unknown. We followed children born to women who participated in the LIMIT randomised trial, where pregnant women were randomised to an antenatal dietary and lifestyle intervention or standard antenatal care. Our aim was to assess the effect of the intervention, on child outcomes at 3–5 years of age on children whose mothers provided consent. We assessed 1418 (Lifestyle Advice n = 727; Standard Care n = 691) (66.9%) of the 2121 eligible children. There were no statistically significant differences in the incidence of child BMI z-score >85th centile for children born to women in the Lifestyle Advice Group, compared with the Standard Care group (Lifestyle Advice 444 (41.73%) versus Standard Care 417 (39.51%); adjusted relative risk (aRR) 1.05; 95% confidence intervals 0.93–1.19; p = 0.42). There were no significant effects on measures of child growth, adiposity, neurodevelopment, or dietary intake. There is no evidence that an antenatal dietary intervention altered child growth and adiposity at age 3–5 years. This cohort of children remains at high risk of obesity, and warrants ongoing follow-up.

In the field of evolutionary genome analysis, biologists seek to identify important genes or chromosome regions by comparing phylogenetic trees and analyzing the mutation at which locus might affect phenotypic traits. Unfortunately, the tree comparison and accompanying analysis are often performed manually. In this paper, we characterize the workflow of evolutionary genome analysis and present a task analysis for the fundamental questions asked by biologists during the analysis procedure. We propose two algorithms to enable quantitative tree comparison. One is to measure the differences between corresponding leaf nodes on two trees, and the other is to compute the classification inconsistency of each leaf node by comparing tree structure with a given biological classification. Configuring with the obtained difference and inconsistency, we present a visual analysis system, visual comparison of phylogenetic trees for evolutionary genome analysis, which not only enables biologists to intuitively explore trees but also identify locus which affects their traits by comparing SNP variants of selected leaf nodes. We conclude with case studies from two biologists who used our system to augment their previous manual analysis workflow and demonstrate that our system can reveal more insight. published

Background The impact of maternal obesity extends beyond birth, being independently associated with an increased risk of child obesity. Current evidence demonstrates that women provided with a dietary intervention during pregnancy improve their dietary quality and have a modest reduction in gestational weight gain. However, the effect of this on longer-term childhood obesity-related outcomes is unknown. Methods We conducted an individual participant data meta-analysis from RCTs in which women with a singleton, live gestation between 10+0 and 20+0 weeks and body mass index (BMI) ≥ 25 kg/m2 in early pregnancy were randomised to a diet and/or lifestyle intervention or continued standard antenatal care and in which longer-term maternal and child follow-up at 3–5 years of age had been undertaken. The primary childhood outcome was BMI z-score above the 90th percentile. Secondary childhood outcomes included skinfold thickness measurements and body circumferences, fat-free mass, dietary and physical activity patterns, blood pressure, and neurodevelopment. Results Seven primary trials where follow-up of participants occurred were identified by a systematic literature search within the International Weight Management in Pregnancy (i-WIP) Collaborative Group collaboration, with six providing individual participant data. No additional studies were identified after a systematic literature search. A total of 2529 children and 2383 women contributed data. Approximately 30% of all child participants had a BMI z-score above the 90th percentile, with no significant difference between the intervention and control groups (aRR 0.97; 95% CI 0.87, 1.08; p=0.610). There were no statistically significant differences identified for any of the secondary outcome measures. Conclusions In overweight and obese pregnant women, we found no evidence that maternal dietary and/or lifestyle intervention during pregnancy modifies the risk of early childhood obesity. Future research may need to target the pre-conception period in women and early childhood interventions. Trial registration PROSPERO, CRD42016047165

Background The immediate impact of providing an antenatal dietary intervention during pregnancy has been extensively studied, but little is known of the effects beyond the neonatal period. Our objective was to evaluate the effect of an antenatal dietary intervention in overweight or obese women on infant outcomes 6 months after birth. Methods We conducted a follow up study of infants born to women who participated in the LIMIT trial during pregnancy. Live-born infants at 6-months of age, and whose mother provided consent to ongoing follow-up were eligible. The primary follow-up study endpoint was the incidence of infant BMI z-score ≥90th centile for infant sex and age. Secondary study outcomes included a range of infant anthropometric measures, neurodevelopment, general health, and infant feeding. Analyses used intention to treat principles according to the treatment group allocated in pregnancy. Missing data were imputed and analyses adjusted for maternal early pregnancy BMI, parity, study centre, socioeconomic status, age, and smoking status. Outcome assessors were blinded to the allocated treatment group. Results A total of 1754 infants were assessed at age 6 months (Lifestyle Advice n = 869; Standard Care n = 885), representing 82.1% of the eligible sample (n = 2136). There were no statistically significant differences in the incidence of infant BMI z-score ≥90th centile for infants born to women in the Lifestyle Advice group, compared with the Standard Care group (Lifestyle Advice 233 (21.71%) vs. Standard Care 233 (21.90%); adjusted relative risk (aRR) 0.99; 95% confidence interval 0.82 to 1.18; p = 0.88). There were no other effects on infant growth, adiposity, or neurodevelopment. Conclusion Providing pregnant women who were overweight or obese with an antenatal dietary and lifestyle intervention did not alter 6-month infant growth and adiposity. Trial Registration: Australian and New Zealand Clinical Trials Registry (ACTRN12607000161426).

Der Energiestoffwechsel des Herzens ist obligatorisch aerob, um den hohen Adenosintriphosphat(ATP)-Bedarf bei geringer ATP-Reserve zu decken. Je nach Verfugbarkeit greift der Herzmuskel auf die verschiedenen Substrate wie Fettsauren, Glucose und Lactat zuruck, sodass ein Substratmangel praktisch ausgeschlossen ist. Eine hocheffiziente Vorwartskopplung von Stoffwechsel und Durchblutung an die Herzarbeit gewahrleistet unter physiologischen Bedingungen die kontinuierliche Anpassung an den ATP-Bedarf. Einschrankungen in der Energieversorgung konnen aber auftreten, wenn die Koronardurchblutung fallt (Flussstopp) oder Diffusionsstrecken fur Sauerstoff zunehmen (Myokardhypertrophie). Hier kommt der Substratwahl eine wichtige Bedeutung fur die Aufrechterhaltung des Energiestoffwechsels zu. Zwar ist der Energiegehalt von Fettsauren hoch, ihre Energieeffizienz ist jedoch deutlich niedriger als diejenige von Kohlenhydraten. Die Kombination von Fasten, Stress, Flussstopp und Heparingabe im Rahmen kardiochirurgischer Eingriffe stellt eine ungunstige Konstellation fur einen effizienten Energiestoffwechsel dar, da hier die Fettsaurespiegel typischerweise hoch sind. Stoffwechselinterventionen zielen auf eine Reduktion der Fettsaureplasmaspiegel bei Steigerung der myokardialen Glucoseaufnahme, z. B. durch normoglykamische Insulin-Glucose-Infusion. Ziel ist die Optimierung des Energiestoffwechsels, um die perioperative Mortalitat bzw. die notwendige Dauer der Intensivtherapie kardiochirurgischer Patienten weiter zu reduzieren.

published

Over-activation of the renin-angiotensin axis and worsening of vascular function are critical contributors to the development of hypertension. Therefore, inhibition of angiotensin-converting enzyme (ACE), a key factor of the renin-angiotensin axis, is a first line treatment of hypertension. Besides pharmaceutical ACE inhibitors, some natural peptides have been shown to exert ACE-inhibiting properties with antihypertensive effects and potentially beneficial effects on vascular function. In this study, the ACE-inhibiting potential and effects on vascular function of tryptophan-containing peptides were evaluated. The ACE inhibitory action and stability of tryptophan-containing peptides was tested in endothelial cells—a major source of whole body ACE activity. Furthermore, the efficacy of peptides on vascular ACE activity, as well as vessel tone was assessed both ex vivo and in vivo. In human umbilical vein endothelial cells (HUVEC), isoleucine-tryptophan (IW) had the highest ACE inhibitory efficacy, followed by glutamic acid-tryptophan (EW) and tryptophan-leucine (WL). Whereas none of the peptides affected basal vessel tone (rat aorta), angiotensin I-induced vasoconstriction was blocked. IW effectively inhibited aortic ACE activity ex vivo taken from SHRs after 14-weeks of oral treatment with IW. Furthermore, IW treated SHRs showed better endothelium-dependent vessel relaxation compared to placebo. This study shows strong ACE-inhibiting effects of IW, EW and WL in HUVECs and aorta. The peptides effectively counteract angiotensin-induced vasoconstriction and preserve endothelium-dependent vessel relaxation. Thus, tryptophan-containing peptides and particularly IW may serve as innovative food additives with the goal of protection from angiotensin II-induced worsening of vascular function.

The micro-crustacean Daphnia pulex is a model species for studying predator-induced defenses. When exposed to chemical cues released by its predator, the phantom midge larvae Chaoborus (Diptera), it develops protective neckteeth that reduce the predator’s success of predation in the juvenile instars. Defensive traits need to be expressed as soon as possible, which requires an early sensitivity to predator cues. We investigated the exact kairomone-sensitive period in three D. pulex strains and the timeline of neckteeth expression in early juvenile instars. We divided embryonic development into five major stages based on successive morphological landmarks. We exposed animals in these developmental stages to kairomones in order to determine the sensitive periods for neckteeth expression in the 1st and 2nd juvenile instar. Our results indicate that kairomone sensitivity starts during embryogenesis when compound eye spots begin to fuse and egg membranes are shed. Neckteeth develop with a stage-dependent time lag, being shorter when exposed in the first kairomone-sensitive stage and longer when exposed in the following developmental stages. Evolution of early kairomone sensitivity and fast defense development is a crucial step in D. pulex’s defenses against Chaoborus as it allows for protection of the most vulnerable juvenile stages.

Estrogen modulates adrenergic reactivity of macrovessels, resulting in weaker α-adrenergic vasoconstriction in females than males. However, the mechanisms governing this important sex-specific difference are not well understood. We hypothesized that vessels of females express more dilatory β-adrenoceptors, which counteract constrictive effects of α-adrenoceptors. This hypothesis was tested using aortas of normotensive (WKY) and hypertensive rats (SHR), along with human mammary artery. Selective blockade of β1 (CGP20712) or β3 (SR59230A), but not β2 (ICI118,551) adrenoceptors, greatly increased α-adrenergic constriction (norepinephrine) of aorta in female SHRs, but not in male SHRs at 12 weeks of age. Consistently, the selective β1/β2 (isoproterenol) and β3-adrenergic (BRL37344) relaxation was stronger in female SHRs than in males. Removal of endothelium and use of L-NMMA abolished sex-difference in α-adrenergic constriction and β-adrenergic relaxation. Immunostainings revealed endothelial localization of β1- and β3-adrenoceptors. mRNA levels of aortic β1- and β3-, but not β2-adrenoceptors were markedly higher in female than in male SHRs. The sex-specific differences in α-adrenergic constriction and β-adrenoceptor mRNA levels were age-dependent, predominantly present up to 29 weeks and disappeared at 36 weeks of age. The sex-specific difference was not strain-dependent and was similarly present in normotensive WKY rats. Human mammary artery of women showed a weaker α-adrenergic constriction than arteries of men. This sex-specific difference was prominent at 45–65 years and disappeared with aging. Our results convincingly demonstrate that female macrovessels express more dilatory β1- and β3-adrenoreceptors than male vessels with a predominant endothelial localization. This sex-specific difference is functionally relevant in young adults and is attenuated with aging.

Entwicklungen in der Displaytechnologie haben in den vergangenen Jahren eine Vielzahl hochauflösender Bildschirme hervorgebracht. Der Forschungsverbund ,,Information at your finger tips – interaktive Visualisierung für Gigapixel Displays“ hat sich mit den Herausforderungen beschäftigt, die diese Technologie für viele Bereiche der Informatik in sich birgt. Hierbei wurden sowohl neue Grafiksysteme untersucht als auch Interaktionsmethoden und Darstellungsformen sowie deren Anwendung in Visualisierung und Kunst.

Hitze und Kalte sind Umweltfaktoren, die erhebliche Auswirkungen auf den Blutkreislauf haben. Bei Erwarmung der Kerntemperatur (Hyperthermie) von ca. 36,5 auf 39°C wird das Herzzeitvolumen verdoppelt. Dies fuhrt im Zusammenhang mit Vasokonstriktionen im Splanchnikusgebiet und in der Skelettmuskulatur zu einer starken Durchblutungszunahme in der Haut. Die zugrunde liegende Gefasdilatation erfolgt vorwiegend reflektorisch uber eine Reduktion α-adrenerger Efferenzen und eine Steigerung sympathisch cholinerger Efferenzen unter Beteiligung von Stickstoffmonoxid. Beim Vorliegen bestimmter Risikofaktoren, wie Alter und Diabetes, kann die Adaptationsfahigkeit unter Hyperthermie eingeschrankt sein. Bei Abnahme der Kerntemperatur (Hypothermie) reagiert das Gefassystem reflektorisch mit einer adrenergen Vasokonstriktion (Noradrenalin). Unterhalb einer Kerntemperatur von 34°C sinkt das Herzzeitvolumen infolge Bradykardie. Im Alter kann die reflektorische Vasokonstriktion gesteigert sein; dies kann insbesondere bei Hypertonikern problematisch werden. Tiefe Narkose schaltet die Regulationsprozesse aus.

The hypothesis was tested that vardenafil, a PDE5 inhibitor, specifically enhances coronary vasodilation during acidosis. In isolated constant pressure perfused guinea pig hearts, infusion of vardenafil (or= 1 microM) increased coronary flow concentration-dependently 34 % above baseline. In parallel, cGMP release increased (0.44 +/- 0.094 vs. 0.14 +/- 0.017 pmol/min x g at 0.5 microM vardenafil vs. baseline). Flow increases occurred in the absence of changes in heart function (LVP, heart rate, dP/dt(max), heart rate - pressure product). Infusion of the NO synthase blocker L-NMMA (100 microM) caused a rightward shift of the dose-response curve of vardenafil. To test whether vardenafil treatment may enhance metabolic coronary vasodilation, arterial pCO(2) was raised from 38 to 61 mmHg, which resulted in a steady state flow increase of 18.8 +/- 4.5%. Infusion of vardenafil, given at a threshold flow enhancing concentration, doubled the coronary flow response during hypercapnic acidosis to 38.4 +/- 4.2 % (p=0.004). This flow amplification during acidosis was not shared by the K(ATP) channel opener cromakalim, indicating a specific effect of vardenafil on flow control during myocardial acidosis. We conclude that vardenafil specifically relaxes coronary resistance vessels through NO/cGMP-dependent pathways and increases the coronary flow response toward hypercapnic acidosis. This finding further supports the importance of the NO-cGMP axis in mediation of this flow response.

Objective: Although it has been shown recently that acetylcholine (ACh)-induced vasodilation of forearm resistance vessels is predominantly mediated by nitric oxide, direct biochemical evidence for eNOS stimulation by bradykinin (BK) in the human arterial circulation is still lacking. Therefore, the present study was designed to test the hypothesis that in the human forearm vasculature eNOS stimulation significantly contributes to BK-induced vasodilation. Methods: BK was infused in the presence and absence of the NOS inhibitor L-NMMA (8 μmol/min) into the brachial artery of 16 healthy volunteers and the effects compared to muscarinergic eNOS stimulation following acetylcholine infusion. Forearm blood flow (FBF) was measured by venous occlusion plethysmography, and plasma nitrite (NO2 −), which represents a sensitive and specific marker of regional eNOS activity, was determined in the antecubital vein and brachial artery by flow injection analysis. Nitric oxide production was calculated as product of the veno-arterial difference of NO2 − concentration times FBF. Results: Kininergic (BK: 20, 60, 200 ng/min) as well as muscarinergic (ACh: 1, 3, 10 μg/min) stimulation resulted in a dose-dependent increase in FBF and NO2 − in each individual. The relationship between FBF and NO production upon BK infusion was comparable to that obtained with ACh (r = 0.98; n = 64, p < 0.01). Moreover, NOS inhibition reduced both flow responses and NO production (BK: 54 and 75 %; ACh: 57 and 72 %) to a similar extent. Conclusions: These data provide direct biochemical evidence for the involvement of eNOS in bradykinin-induced vasodilation of forearm resistance vessels in humans.

In diesem Artikel geben wir eine grundlegende Einfuhrung in die algorithmischen Empfehlungssysteme und wie sie – unter Umstanden – Filterblasen und Echokammern in sozialen Medien erzeugen konnten. Der Term Filterblase beschreibt dabei das Phanomen, dass wir von Algorithmen hauptsachlich solche Themen wieder vorgeschlagen bekommen, die wir schon mogen. Als Echokammern bezeichnet man Freundesgruppen, die hauptsachlich aus Leuten mit ahnlicher Meinung bestehen, in denen also jede Aussage widerhallt. Auch wenn es noch keine Studien gibt, die wirklich nachweisen, dass Menschen heutzutage durch die Wirkung von Algorithmen tatsachlich in dichteren Filterblasen leben oder in der Bildung von Echokammern bestarkt werden, ist doch klar, dass mit Hilfe dieser Algorithmen unsere Meinungsbildung manipuliert werden konnte. Daher sprechen wir uns fur eine sinnvolle Uberwachung von solchen Algorithmen aus, um eine solche Manipulation uberhaupt entdecken zu konnen.

Overweight and obesity during pregnancy represents a considerable health burden. While research has focused on interventions to limit gestational weight gain, there is little information describing their impact on neonatal health. Our aim was to investigate the effect on a range of pre-specified secondary neonatal outcomes of providing antenatal dietary and lifestyle advice to women who are overweight or obese. We report a range of pre-specified secondary neonatal outcomes from a large randomised trial in which antenatal dietary and lifestyle advice was provided to women who were overweight or obese. Pregnant women were eligible for participation with a body mass index of 25 kg/m2 or over, and singleton gestation between 10+0 and 20+0 weeks. Outcome measures included gestational age at birth; Apgar score below 7 at 5 minutes of age; need for resuscitation at birth; birth weight above 4.5 kg or below 2.5 kg; birth weight, length and head circumference (and Z-scores); admission to the nursery; respiratory distress syndrome; and postnatal length of stay. Data relating to the primary outcome (large for gestational age infants defined as birth weight above the 90th centile) and birth weight above 4 kg have been reported previously. Analyses used intention-to-treat principles. In total, 2,142 infants were included in the analyses. Infants born to women following lifestyle advice were significantly less likely to have birth weight above 4.5 kg (2.15% versus 3.69%; adjusted risk ratio (aRR) = 0.59; 95% confidence interval (CI) 0.36 to 0.98; P = 0.04), or respiratory distress syndrome (1.22% versus 2.57%; aRR = 0.47; 95% CI 0.24 to 0.90; P = 0.02), particularly moderate or severe disease, and had a shorter length of postnatal hospital stay (3.94 ± 7.26 days versus 4.41 ± 9.87 days; adjusted ratio of means 0.89; 95% CI 0.82 to 0.97; P = 0.006) compared with infants born to women who received Standard Care. For women who are overweight or obese, antenatal dietary and lifestyle advice has health benefits for infants, without an increase in the risk of harm. Continued follow-up into childhood will be important to assess the longer-term effects of a reduction in high infant birth weight on risk of child obesity. Please see related articles: http://www.biomedcentral.com/1741-7015/12/161 and http://www.biomedcentral.com/1741-7015/12/201 . Australian and New Zealand Clinical Trials Registry ( http://ACTRN12607000161426 )

Chronic activation of angiotensin II (ANGII) and matrix metalloproteinase-2 (MMP-2) during hypertension contributes to increased aortic stiffness. We studied signalling mechanisms employed by ANGII in the regulation of latent (pro-) and active forms of MMP-2 in rat aortic endothelial and smooth muscle cells, along with isolated rat aorta. Using western blotting, we demonstrate that ANGII (1 µmol/L) significantly (P < 0.01) increases pro-MMP-2 protein expression after 8 h not only in endothelial and smooth muscle cells, but also in isolated rat aorta. We demonstrate that ANGII acts via AT1 receptor-activated cell-specific pathways. In endothelial cells, the JNK1/c-jun pathway is activated, whereas in smooth muscle cells, the JAK2/STAT3 pathway. Activation of JAK2/STAT3 pathway in response to ANGII was EGF receptor-dependent. Results obtained in cell culture are in agreement with the results obtained in isolated aorta. However, active MMP-2 was not found under cell culture conditions, whereas in isolated aorta, active MMP-2 was significantly (P < 0.05) increased after stimulation with ANGII, as detected by gelatine zymography. This increase of MMP-2 activity was not inhibited by blocking the pathways we identified to control pro-MMP-2 protein expression, but was abolished in the absence of endothelium. Our findings demonstrate that ANGII regulates pro-MMP-2 protein expression via cell-specific pathways in rat aorta. The endothelium may play an essential role in the activation of pro-MMP-2. These results may lead to new strategies for inhibiting MMP-2 expression and activity in distinct cell types of the aortic wall.

Since late eighties scientists in computer graphics elaborate nonrealistic rendering techniques in addition to realistic image generation. The present article gives an overview by describing three different techniques: computer generated copper plates as an example for the imitation of traditional printing techniques, synthetic stipple drawings for use in scientific illustration and pen-and-ink illustrations of plants with applications in landscaping.

N-Aryl-N-hydroxy urethanes (AHUs), which are promising N*OH mediators for oxidoreductase catalysis, are electrochemically active redox compounds with a redox potential of 0.35–0.40 V vs. SCE (0.59–0.64 V vs. NHE). Alkyl substituents in the carbamic acid residue have, as expected, only little influence on the redox potential. The highest potential was noticed for N-hydroxy-N-(4-cyanophenyl)-carbamic acid methyl ester. Recombinant Coprinus cinereus peroxidase (rCiP) catalyzes oxidation of the AHUs with apparent bimolecular constants k ox of 2.5ċ104–7.5ċ104 M −1s−1 at pH = 8.5 and 25°C. Structure-function connectivities of the substrates were analysed within the framework of the Marcus cross relationship and by using ab initio quantum chemical calculations. An excellent correlation of the redox potentials and the HOMO energies could be found. However, no correlation of log(k ox) with redox potential and HOMO energy was indicated as predicted by theory. This was explained by specific docking of the substrates in the active center of rCiP.

The quantitatively most important source of adenosine under well-oxygenated conditions is 5'-AMP hydrolyzed by cytosolic 5'-nucleotidase N-I. Hydrolysis of S-adenosylhomocysteine and extracellular dephosphorylation of 5'-AMP further contribute to total production. More than 90% of the total production occur intracellularly under well-oxygenated conditions. Besides cardiomyocytes, endothelial cells and smooth muscle contribute significantly to total cardiac adenosine production. Rapid enzymatic conversion of adenosine is provided by adenosine kinase and adenosine deaminase, keeping the cytosolic adenosine concentration in the nanomolar range. Due to the high intracellular rates of adenosine rephosphorylation and deamination the cytosolic is normally below the extracellular adenosine concentration, making the cytosol to a sink rather than a source of adenosine. It is for this reason that blockers of membrane transport enhance the plasma adenosine concentration. With increasing catabolism of adenine nucleotides the rate of intracellular adenosine production exceeds the rate of adenosine deamination and rephosphorylation. Thus, this condition will result in a concentration gradient from intra- to extracellular. Thence, membrane transport blockers would be expected to increase the intracellular adenosine concentration. A considerable insecurity on the importance of experimental data results from species differences of purine metabolism. Cardiac adenosine metabolism has recently been described in quantitative terms using mathematical model analysis. This analysis tool may prove useful in future when (1) clarifying the importance of various regulatory actions described for the different pathways of adenosine metabolism, (2) making quantitative comparisons of different experimental models possible and (3) deepening the insight from experimental data.