Observations on the ecology and behavior of the giant river otter Pteronura brasiliensis in Suriname

L'écologie et le comportement de la Loutre géante du Brésil Pteronura brasiliensis ont été étudiés de juillet 1977 à mars 1978 au Suriname. L'espèce est diurne et grégaire, formant des groupes familiaux durables qui défendent certaines portions de leur domaine vital contre les incursions de leurs congénères. Pteronura brasiliensis est piscivore. Les modalités de reproduction et les déplacements saisonniers des poissons Characoides qui forment l'essentiel de son régime ont une influence profonde sur l'écologie de cette loutre. Pendant la saison des pluies, par exemple, les Pteronura suivent leurs proies dans la forêt inondée, abandonnant temporairement leurs « bivouacs » et tanières habituels. La reproduction a lieu d'août à octobre. Les jeunes loutres restent avec leurs parents quand naît la portée suivante, peut-être même jusqu'à leur propre maturité. Le répertoire comportemental de Pteronura brasiliensis est décrit et comparé avec celui des Lutra solitaires. Lutra enudris peut cohabiter avec Pteronura dans certains cours d'eau de Suriname. Ses moeurs solitaires, son activité surtout crépusculaire et la taille moyenne de ses proies, tout comme le fait qu'elle peut également habiter dans les marais côtiers et les petites rivières de la grande forêt, minimisent les chances d'une éventuelle compétition avec Pteronur

Vocal repertoire of the social giant otter

According to the “social intelligence hypothesis,” species with complex social interactions have more sophisticated communication systems. Giant otters (Pteronura brasiliensis) live in groups with complex social interactions. It is likely that the vocal communication of giant otters is more sophisticated than previous studies suggest. The objectives of the current study were to describe the airborne vocal repertoire of giant otters in the Pantanal area of Brazil, to analyze call types within different behavioral contexts, and to correlate vocal complexity with level of sociability of mustelids to verify whether or not the result supports the social intelligence hypothesis. The behavior of nine giant otters groups was observed. Vocalizations recorded were acoustically and statistically analyzed to describe the species’ repertoire. The repertoire was comprised by 15 sound types emitted in different behavioral contexts. The main behavioral contexts of each sound type were significantly associated with the acoustic variable ordination of different sound types. A strong correlation between vocal complexity and sociability was found for different species, suggesting that the communication systems observed in the family mustelidae support the social intelligence hypothesis

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

Observations on the ecology and behavior of the Giant River Otter Pteronura brasiliensis in Suriname

L’écologie et le comportement de la Loutre géante du Brésil Pteronura brasiliensis ont été étudiés de juillet 1977 à mars 1978 au Suriname. L’espèce est diurne et grégaire, formant des groupes familiaux durables qui défendent certaines portions de leur domaine vital contre les incursions de leurs congénères. Pteronura brasiliensis est piscivore. Les modalités de reproduction et les déplacements saisonniers des poissons Characoides qui forment l’essentiel de son régime ont une influence profonde sur l’écologie de cette loutre. Pendant la saison des pluies, par exemple, les Pteronura suivent leurs proies dans la forêt inondée, abandonnant temporairement leurs «bivouacs » et tanières habituels. La reproduction a lieu d’août à octobre. Les jeunes loutres restent avec leurs parents quand naît la portée suivante, peut-être même jusqu’à leur propre maturité. Le répertoire comportemental de Pteronura brasiliensis est décrit et comparé avec celui des Lutra solitaires. Lutra enudris peut cohabiter avec Pteronura dans certains cours d’eau de Suriname. Ses mœurs solitaires, son activité surtout crépusculaire et la taille moyenne de ses proies, tout comme le fait qu’elle peut également habiter dans les marais côtiers et les petites rivières de la grande forêt, minimisent les chances d’une éventuelle compétition avec Pteronura.Duplaix Nicole. Observations on the ecology and behavior of the Giant River Otter Pteronura brasiliensis in Suriname. In: Revue d'Écologie (La Terre et La Vie), tome 34, n°4, 1980. pp. 495-620

Fayard, A. (Editeur). — Atlas des mammifères sauvages de France. Ouvrage collectif réalisé sous la direction de Armand Fayard, pour le compte du Ministère de l’Environnement, avec la participation du Secrétariat de la Faune et de la Flore. Paris, 1984, Société Française pour l’Etude et la Protection des Mammifères

Duplaix Nicole. Fayard, A. (Editeur). — Atlas des mammifères sauvages de France. Ouvrage collectif réalisé sous la direction de Armand Fayard, pour le compte du Ministère de l’Environnement, avec la participation du Secrétariat de la Faune et de la Flore. Paris, 1984, Société Française pour l’Etude et la Protection des Mammifères. In: Revue d'Écologie (La Terre et La Vie), tome 40, n°2, 1985. pp. 276-277

Klopfer, P.H. et Hailman, J. P. - An introduction to animal Behavior. Ethology's first century. Englewood Cliffs, New Jersey, Prentice-Hall, 1967

Duplaix Nicole. Klopfer, P.H. et Hailman, J. P. - An introduction to animal Behavior. Ethology's first century. Englewood Cliffs, New Jersey, Prentice-Hall, 1967. In: La Terre et La Vie, Revue d'Histoire naturelle, tome 21, n°4, 1967. pp. 477-478

Golley F. B. (Editor) — Tropical rain forest ecosystems. Part A. Structure and function. Amsterdam, Oxford and New York, Elsevier Scientific Publishing Company, Ecosystems of the World, volume 14 A, 1983

Duplaix N. Golley F. B. (Editor) — Tropical rain forest ecosystems. Part A. Structure and function. Amsterdam, Oxford and New York, Elsevier Scientific Publishing Company, Ecosystems of the World, volume 14 A, 1983. In: Revue d'Écologie (La Terre et La Vie), tome 38, n°2, 1983. pp. 244-245