Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.

Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Students´ Perception of Real-Time Quiz Kahoot! As a Review Tool in Higher Education: A Case of Study

The use of gamification has spread in recent years, proving to be an effective tool to increase student motivation. Among them stands out Kahoot!, an online questionnaire in which students compete among themselves by counting both the number of correct answers and the response speed. Its effectiveness has been tested mainly in primary and secondary students, with much less available information at higher levels. This study evaluates the opinion of 48 students in Plant Science, a subject of 2nd course of Agricultural Engineering Grade, after carrying out three Kahoot! questionnaires with 12 questions with a single-answer, with two weeks between one and the next. To evaluate the contents fixation a reunified quiz was done, one week after the last Kahoot!, chosen randomly five questions from each questionnaire. The satisfaction of more than 90% of the students was positive or very positive, mainly because of creating a more positive and participatory learning environment. The use as a scoring tool produces a decrease in the acceptance in some students, producing anxiety in 25% of the students, due to the limited available time in about 27% of students. Furthermore Kahoot! has been found as a efficient tool for consolidating knowledge, as the number of questions that the students have consolidated is greater than 20% in the three questionnaires carried out, regardless of whether the period elapsed was 5, 3 or 1 week

Leopoldo Olea Márquez de Prado 20 de octubre de 1943 - 8 de mayo de 2016, Socio de Honor de la SEEP.

In memoria

INFLUENCIA DE LA CALIDAD DEL TERRENO EN LA RESPUESTA DE LOS PASTOS A LA APLICACIÓN DE FÓSFORO = INFLUENCE OF SOIL QUALITY IN THE RESPONSE OF PASTURES TO THE PHOSPHORUS APPLICATION

ResumenEn el suroeste extremeño los pastos son de producción muy irregular y escasa calidad nutritiva. Tradicionalmente los ga- naderos de esta área clasifican las zonas de su finca en malas y buenas, realizando fertilización fosfórica únicamente en parte de las buenas. Con el fin de evaluar la influencia de la calidad del terreno en la respuesta del pasto a la fertili- zación fosfórica, se diseñó un experimento en dos fincas de la comarca de La Serena (Badajoz) consistente en la apli- cación o no de 250 kg ha-1 de superfosfato de cal al 18% en dos zonas diferenciadas según la pendiente, la profundidad  y la pedregosidad del terreno. En tres campañas agrícolas, se analizó la composición botánica, la producción, proteína bruta y digestibilidad de materia orgánica del pasto, tanto en invierno como en primavera. La proteína y la digestibilidad del pasto invernal mejoró en la zona mala por la fertilización fosfórica (aumentó de 15% a 16%), así como el porcentaje de leguminosas que aumentó de 20% aa 30%. Por tanto, existe respuesta positiva a la aportación de fósforo en zonas clasificadas por los ganaderos como malas, mostrando potencial de mejora de calidad y composición botánica.AbstractIn the southwest of Extremadura pastures show a very irregular production and low nutritional value. In this zone, farmers classified their farm’s areas in bad and good, and fertilization with phosphate is made only in good areas. In this study we evaluated the soil quality influence on the pasture improvement when phosphoric fertilizer was used. The experiment was conducted in two farms in the region of La Serena (Badajoz), where the main plot was the quality of the soil differentiated based on slope, depth and stoniness, and the sub-plot was the fertilization. Superphosphate of lime to 18% at a rate of 250 kg ha-1 was applied, having a control area without fertilization. This experiment was replicated in three different agro- nomical years, and the botanical composition of pasture, the production in dry matter, the crude protein and the organic matter digestibility of grass in winter and spring were analyzed. Protein and digestibility of winter grass in bad areas were improved by phosphorus fertilization (increasing from 15% to 16%) and the percentage of legumes changed from 20% to 30%. There is, therefore, a positive contribution of phosphorus in classified areas as bad by farmers, showing them an improvement potential regarding to pasture quality and botanical composition