Discriminating unifloral honey from a dioecious mass flowering tree of Brazilian seasonally dry tropical forest through pollen spectra: consequences of honeybee preference for staminate flowers

International audienceMyracrodruon urundeuva (“aroeira”) is a dioecious tree of the seasonally dry tropical forest (SDTF) of Brazil and source of a unique unifloral honey. To discriminate this honey by its pollen spectra, we compared melissopalynological analysis of reference honey samples with those of other samples collected in the SDTF belt. Reference honeys had on average 99% of aroeira pollen, while the other honey samples averaged 84% of this pollen. We used the receiver operating characteristic (ROC) curve, applied here for the first time in honey analysis, for determining the cut-off value of at least 93% of Myracrodruon pollen in a sample for classifying unifloral aroeira honey. The over-representation of aroeira pollen in this honey reflects that honeybees visited ten times as many staminate flowers as pistillate flowers. We conclude that unifloral aroeira honey has uniform pollen spectra, as a byproduct of the preference of honeybees for staminate flowers

Does Seasonality Affect the Nest Productivity, Body Size, and Food Niche of Tetrapedia curvitarsis Friese (Apidae, Tetrapediini)?

Tetrapedia curvitarsis Friese is a widely distributed species, frequently attracted by trap-nests. Previous studies have revealed a higher frequency of nesting in the wet season and dimorphism between the sexes, with females exhibiting larger body size than males. We evaluated the effects of seasonality on the production of nests, food niche, and body size of T. curvitarsis. The study was conducted from April 2009 to March 2010 and from April 2012 to March 2013 at the Água Limpa Experimental Station, located in the Triângulo Mineiro, Minas Gerais State. The number of cells was positively correlated with length and diameter of trap-nests. However, the number of nests and the number of cells produced did not differed between the seasons. The females demonstrated a larger head width than males and both presented greater body size in the wet season. However, there was no interaction between sex and season. A higher food niche breadth was observed in the wet season and low similarity in the use of pollen sources between seasons (PS=39.05%). Thus, it is concluded that the season has no effect on the production of nests or cells, but rather on the body size of males and females and food niche breadth. The production of smaller individuals in the dry season could be related not only to the quantity but also the quality of food offered to immature bees

Content of phenolic compounds in monofloral aroeira honey and in floral nectary tissue

O objetivo deste trabalho foi quantificar os compostos fenólicos totais no mel monofloral de aroeira (Astronium urundeuva) e verificar, por meio de testes histoquímicos, se estes compostos estão presentes nos tecidos florais. O apiário, com abelhas Apis mellifera, foi instalado em meio a aroeiras, na região do semiárido do estado de Minas Gerais, Brasil. A partir da anatomia das flores e da raque da inflorescência, observou-se epiderme ornamentada, tricomas tectores e glandulares, idioblastos e sistema secretor desenvolvido. O mel de aroeira apresenta, em média, 142.5±22.6 mg 100 g-1 de compostos fenólicos totais, valor considerado muito elevado quando comparado aos de outros méis monoflorais provenientes do Brasil e do mundo. Os testes histoquímicos detectaram a presença de substâncias fenólicas nos idioblastos e nos ductos secretores associados ao floema nos tecidos florais, especialmente no parênquima nectarífero, na epiderme e nos tricomas glandulares. Os compostos fenólicos estão presentes no tecido floral de ambos os morfos florais, principalmente no nectário onde as abelhas coletam o néctar. Os resultados obtidos são os primeiros, na literatura, indicativos de que os compostos fenólicos produzidos pelas árvores de aroeira são transferidos através do néctar para o mel. Este estudo contribui para o estabelecimento de padrões de qualidade do mel de aroeira e para a identificação da sua origem botânica.The objective of this work was to quantify the content of total phenolic compounds in monofloral honey from aroeira (Astronium urundeuva) trees and to verify, through histochemical tests, if these compounds are present in the floral tissues. The apiary, with Apis mellifera bees, was installed among aroeira trees in the semiarid region of the state of Minas Gerais, Brazil. From the anatomy of the flowers and of the inflorescence rachis, an ornamented epidermis, tector and glandular trichomes, idioblasts, and a developed secretory system were observed. Aroeira honey has an average phenolic content of 142.5±22.6 mg 100 g-1, a value considered very high when compared with those of other monofloral honeys from Brazil and around the world. Histochemical tests detected the presence of phenolic substances in the idioblasts and secretory ducts associated with the phloem in the floral tissues, especially in the nectar parenchyma, epidermis, and glandular trichomes. Phenolic compounds are present in the floral tissue of both floral morphs, mainly in the nectary where honeybees collect nectar. The obtained results are the first, in the literature, indicative that the phenolic compounds produced by aroeira trees are transferred through the nectar to the honey. This study contributes to the establishment of quality standards for monofloral aroeira honey and to the identification of its botanical origin

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

Figure 1 in Food niche of Exomalopsis (Exomalopsis) fulvofasciata Smith (Hymenoptera: Apidae) in Brazilian savannah: the importance of oil-producing plant species as pollen sources

Figure 1. Number of Exomalopsis fulvofasciata recorded on Byrsonima flowers in the two savannah areas. Ecological Station of Panga, MG (ESP) – 1 to 9 and State Park of Serra de Caldas Novas, GO (SPSCN) – 10 to18.Published as part of <i>Rabelo, Laíce Souza, Bastos, Esther Margarida Alves Ferreira & Augusto, Solange Cristina, 2016, Food niche of Exomalopsis (Exomalopsis) fulvofasciata Smith (Hymenoptera: Apidae) in Brazilian savannah: the importance of oil-producing plant species as pollen sources, pp. 1859-1873 in Journal of Natural History 50</i> on page 1864, DOI: 10.1080/00222933.2016.1169328, <a href="http://zenodo.org/record/3993335">http://zenodo.org/record/3993335</a&gt

Figure 5 in Food niche of Exomalopsis (Exomalopsis) fulvofasciata Smith (Hymenoptera: Apidae) in Brazilian savannah: the importance of oil-producing plant species as pollen sources

Figure 5. Abundance of pollen types according to grain size categories: small (S) and medium (M) in two natural areas. (A) Ecological Station of Panga, MG (ESP), and (B) State Park of Serra de Caldas Novas, GO (SPSCN).Published as part of <i>Rabelo, Laíce Souza, Bastos, Esther Margarida Alves Ferreira & Augusto, Solange Cristina, 2016, Food niche of Exomalopsis (Exomalopsis) fulvofasciata Smith (Hymenoptera: Apidae) in Brazilian savannah: the importance of oil-producing plant species as pollen sources, pp. 1859-1873 in Journal of Natural History 50</i> on page 1867, DOI: 10.1080/00222933.2016.1169328, <a href="http://zenodo.org/record/3993335">http://zenodo.org/record/3993335</a&gt