ANOCA patients with and without coronary vasomotor dysfunction present with limited electrocardiographic remodeling

Background: Coronary vasomotor dysfunction (CVDys) comprises coronary vasospasm (CVS) and/or coronary microvascular dysfunction (CMD) and is highly prevalent in patients with angina and non-obstructive coronary artery disease (ANOCA). Invasive coronary function testing (CFT) to diagnose CVDys is becoming more common, enabling pathophysiologic research of CVDys. This study aims to explore the electrophysiological characteristics of ANOCA patients with CVDys. Methods: We collected pre-procedural 12-lead electrocardiograms of ANOCA patients with CVS (n = 35), CMD (n = 24), CVS/CMD (n = 26) and patients without CVDys (CFT-, n = 23) who participated in the NL-CFT registry and underwent CFT. Heart axis and conduction times were compared between patients with CVS, CMD or CVS/CMD and patients without CVDys. Results: Heart axis, heart rate, PQ interval and QRS duration were comparable between the groups. A small prolongation of the QT-interval corrected with Bazett (QTcB) and Fridericia (QTcF) was observed in patients with CVDys compared to patients without CVDys (CVS vs CFT-: QTcB = 422 ± 18 vs 414 ± 18 ms (p = 0.14), QTcF = 410 ± 14 vs 406 ± 12 ms (p = 0.21); CMD vs CFT-: QTcB = 426 ± 17 vs 414 ± 18 ms (p = 0.03), QTcF = 413 ± 11 vs 406 ± 12 ms (p = 0.04); CVS/CMD vs CFT-: QTcB = 424 ± 17 vs 414 ± 18 ms (p = 0.05), QTcF = 414 ± 14 vs 406 ± 12 ms (p = 0.04)). Conclusions: Pre-procedural 12-lead electrocardiograms were comparable between patients with and without CVDys undergoing CFT except for a slightly longer QTc interval in patients with CVDys compared to patients without CVDys, suggesting limited cardiac remodeling in patients with CVDys

Guelb el Ahmar (Bathonian, Anoual Syncline, eastern Morocco): First continental flora and fauna including mammals from the Middle Jurassic of Africa

We report the discovery in Mesozoic continental “red beds” of Anoual Syncline, Morocco, of the new Guelb el Ahmar (GEA) fossiliferous sites in the Bathonian Anoual Formation. They produced one of the richest continental biotic assemblages from the Jurassic of Gondwana, including plants, invertebrates and vertebrates. Both the sedimentological facies and the biotic assemblage indicate a lacustrine depositional environment. The flora is represented by tree trunks (three families), pollen (13 species, five major clades) and charophytes. It suggests local forests and humid (non-arid) conditions. The vertebrate fauna is dominated by microvertebrates recovered by screening–washing. It is rich and diverse, with at least 29 species of all major groups (osteichthyans, lissamphibians, chelonians, diapsids, mammals), except chondrichthyans. It includes the first mammals discovered in the Middle Jurassic of Arabo-Africa. The GEA sites yielded some of the earliest known representatives of osteoglossiform fishes, albanerpetontid and caudate amphibians, squamates (scincomorphans, anguimorphan), cladotherian mammals, and likely choristoderes. The choristoderes, if confirmed, are the first found in Gondwana, the albanerpetontid and caudatan amphibians are among the very few known in Gondwana, and the anguimorph lizard is the first known from the Mesozoic of Gondwana. Mammals (Amphitheriida, cf. Dryolestida) remain poorly known, but are the earliest cladotherians known in Gondwana. The GEA biotic assemblage is characterized by the presence of Pangean and Laurasian (especially European) taxa, and quasi absence of Gondwanan taxa. The paleobiogeographical analysis suggests either a major fossil bias in Gondwana during the Middle Jurassic, and an overall vicariant Pangean context for the GEA assemblage, or alternatively, noticeable Laurasian (European) affinities and North-South dispersals. The close resemblance between the Bathonian faunas of GEA and Britain is remarkable, even in a Pangean context. The similarity between the local Anoual Syncline Guelb el Ahmar and Ksar Metlili faunas raises questions on the ?Berriasian age of the latter

Impact of symptom duration and mechanical circulatory support on prognosis in cardiogenic shock complicating acute myocardial infarction

BACKGROUND: Mortality rates in patients with cardiogenic shock complicating acute myocardial infarction (AMICS) remain high despite advancements in AMI care. Our study aimed to investigate the impact of prehospital symptom duration on the prognosis of AMICS patients and those receiving mechanical circulatory support (MCS). METHODS AND RESULTS: We conducted a retrospective cohort study with data registered in the Netherlands Heart Registration. A total of 1,363 patients with AMICS who underwent percutaneous coronary intervention between 2017 and 2021 were included. Patients presenting after out-of-hospital cardiac arrest were excluded. Most patients were male (68%), with a median age of 69 years (IQR 61-77), predominantly presenting with ST-elevation myocardial infarction (86%). The overall 30-day mortality was 32%. Longer prehospital symptom duration was associated with a higher 30-day mortality with the following rates:  24 h was associated with significantly higher mortality compared to symptom duration of  24 h symptom duration, age and in-hospital cardiac arrest as predictors of 30-day mortality in MCS patients. CONCLUSION: Prolonged prehospital symptom duration was associated with significantly increased 30-day mortality in patients presenting with AMICS. In AMICS patients treated with MCS, a symptom duration of > 24 h was an independent predictor of poor survival. These results emphasise the critical role of early recognition and intervention in the prognosis of AMICS patients

Modélisation de la production de biomasse de microalgues dans des bassins sous serres

3rd year engineering internship repor

Optimizing CO2 transfer in algal open ponds

International audienceThe objective of this study was to optimize the CO2 injection system of algal raceway open ponds to minimize CO2 losses to the atmosphere and therefore reduce operational costs. CO2 transfers can be optimized by increasing the bubble-to-culture CO2 transfer rate and by decreasing the culture-to-atmosphere CO2 transfer rate. CO2 transfer coefficients were first experimentally determined on a pilot-scale algal pond for different designs of the injection system. The impact of five design parameters was tested: the CO2 diffuser length, the CO2 diffuser position, the CO2 flow rate, the paddle wheel rotation speed and the water level. Culture-to-atmosphere transfer coefficient was only significantly impacted by the paddle wheel rotation speed (range: 3.42–48.7 10−3 min−1; base-case value: 17.1 10−3 min−1). Bubble-to-culture transfer coefficient, determined for a mix of fine and coarse CO2 bubbles, varied significantly with the CO2 injection flow rate (range: 1.47–18.3 10−4 min−1; base-case value: 9.11 10−4 min−1) and water level (range: 7.46–14.4 10−4 min−1). The efficiencies of the various system designs at full-scale were then extrapolated through simulation by coupling an algal productivity model to the CO2 transfer model developed in this study. Reducing the water level from 0.2 m down to 0.1 m reduced CO2 supply by 14%. Reducing the paddle wheel rotation speed from 21 rpm to 13 rpm decreased CO2 supply by 40%. Increasing the pH set point from 7.2 to 8 reduced CO2 supply by 38% but also decreased Dunaliella salina biomass productivity by 17%. A trade-off must be achieved between high biomass productivity and lower environmental footprint

Modelling an Artificial Microalgae-Cyanobacteria Ecosystem

International audienceMicroalgae based processes have been actively studied in the last decades with perspective for food, feed, and source of chemicals such as biofuels. Most of the developments focused on monospecific culture of microalgae, with dedicated practices to avoid any contaminations. However, interactions between microalgae and bacteria are likely to enhance microalgae growth, provide more resilience to external changes and eventually limit external contaminations. But interactions within these natural ecosystems are still poorly understood and are affected by the environment. A photosynthetic marine ecosystem composed of the microalgae Dunaliella salina and the nitrogen fixing cyanobacteria Crocosphaera watsonii was therefore studied. A model was designed to represent the competition for light and the interactions with nitrogen between these two microorganisms. An allelopathic effect was noticed and a toxin production by C. watsonii was assumed and included in the model. Calibration was carried out with experimental data where cell densities and nitrate concentrations were measured. The predictions of the mathematical model accurately represented the experimental data. The model therefore highlighted the interactions within this artificial ecosystem. The model confirms that D. salina growth was limited by nitrate concentration and did not consume dissolved organic nitrogen produced by C. watsonii from its diazotrophic activity. D. salina and C. watsonii were competing for light, which favored D. salina and limited C. watsonii when grown in cocultures. The model supports the hypothesis that C. watsonii produced toxins enhancing D. salina mortality in the cocultures

Continuous Versus Bolus Thermodilution‐Derived Coronary Flow Reserve and Microvascular Resistance Reserve and Their Association With Angina and Quality of Life in Patients With Angina and Nonobstructive Coronaries: A Head‐to‐Head Comparison

Background Coronary flow reserve (CFR) and microvascular resistance reserve (MRR) are physiological parameters to assess coronary microvascular dysfunction. CFR and MRR can be assessed using bolus or continuous thermodilution, and the correlation between these methods has not been clarified. Furthermore, their association with angina and quality of life is unknown. Methods and Results In total, 246 consecutive patients with angina and nonobstructive coronary arteries from the multicenter Netherlands Registry of Invasive Coronary Vasomotor Function Testing (NL‐CFT) were investigated. The 36‐item Short Form Health Survey Quality of Life and Seattle Angina questionnaires were completed by 153 patients before the invasive measurements. CFR and MRR were measured consecutively with bolus and continuous thermodilution. Mean continuous thermodilution‐derived coronary flow reserve (CFRabs) was significantly lower than mean bolus thermodilution‐derived coronary flow reserve (CFRbolus) (2.6±1.0 versus 3.5±1.8; P<0.001), with a modest correlation (ρ=0.305; P<0.001). Mean continuous thermodilution‐derived microvascular resistance reserve (MRRabs) was also significantly lower than mean bolus thermodilution‐derived MRR (MRRbolus) (3.1±1.1 versus 4.2±2.5; P<0.001), with a weak correlation (ρ=0.280; P<0.001). CFRbolus and MRRbolus showed no correlation with any of the angina and quality of life domains, whereas CFRabs and MRRabs showed a significant correlation with physical limitation (P=0.005, P=0.009, respectively) and health (P=0.026, P=0.012). In a subanalysis in patients in whom spasm was excluded, the correlation further improved (MRRabs versus physical limitation: ρ=0.363; P=0.041, MRRabs versus physical health: ρ=0.482; P=0.004). No association with angina frequency and stability was found. Conclusions Absolute flow measurements using continuous thermodilution to calculate CFRabs and MRRabs weakly correlate with, and are lower than, the surrogates CFRbolus and MRRbolus. Absolute flow parameters showed a relationship with physical complaints. No relationship with angina frequency and stability was found

ANOCA patients with and without coronary vasomotor dysfunction present with limited electrocardiographic remodeling

Background: Coronary vasomotor dysfunction (CVDys) comprises coronary vasospasm (CVS) and/or coronary microvascular dysfunction (CMD) and is highly prevalent in patients with angina and non-obstructive coronary artery disease (ANOCA). Invasive coronary function testing (CFT) to diagnose CVDys is becoming more common, enabling pathophysiologic research of CVDys. This study aims to explore the electrophysiological characteristics of ANOCA patients with CVDys. Methods: We collected pre-procedural 12-lead electrocardiograms of ANOCA patients with CVS (n = 35), CMD (n = 24), CVS/CMD (n = 26) and patients without CVDys (CFT-, n = 23) who participated in the NL-CFT registry and underwent CFT. Heart axis and conduction times were compared between patients with CVS, CMD or CVS/CMD and patients without CVDys. Results: Heart axis, heart rate, PQ interval and QRS duration were comparable between the groups. A small prolongation of the QT-interval corrected with Bazett (QTcB) and Fridericia (QTcF) was observed in patients with CVDys compared to patients without CVDys (CVS vs CFT-: QTcB = 422 ± 18 vs 414 ± 18 ms (p = 0.14), QTcF = 410 ± 14 vs 406 ± 12 ms (p = 0.21); CMD vs CFT-: QTcB = 426 ± 17 vs 414 ± 18 ms (p = 0.03), QTcF = 413 ± 11 vs 406 ± 12 ms (p = 0.04); CVS/CMD vs CFT-: QTcB = 424 ± 17 vs 414 ± 18 ms (p = 0.05), QTcF = 414 ± 14 vs 406 ± 12 ms (p = 0.04)). Conclusions: Pre-procedural 12-lead electrocardiograms were comparable between patients with and without CVDys undergoing CFT except for a slightly longer QTc interval in patients with CVDys compared to patients without CVDys, suggesting limited cardiac remodeling in patients with CVDys