The radiation of nodulated Chamaecrista species from the rainforest into more diverse habitats has been accompanied by a reduction in growth form and a shift from fixation threads to symbiosomes Patricia Alves Casaes, José Miguel Ferreira dos Santos, Verônica Cordeiro Silva, Mariana Ferreira Kruschewsky Rhem, Matheus Martins Teixeira Cota, et al. Journal of Experimental Botany, 2024 All non-Mimosoid nodulated genera in the legume subfamily Caesalpinioideae confine their rhizobial symbionts within cell wall-bound ‘fixation threads’ (FTs). The exception is the large genus Chamaecrista in which shrubs and subshrubs house their rhizobial bacteroids more intimately within symbiosomes, whereas large trees have FTs. This study aimed to unravel the evolutionary relationships between Chamaecrista growth habit, habitat, nodule bacteroid type, and rhizobial genotype. The growth habit, bacteroid anatomy, and rhizobial symbionts of 30 nodulated Chamaecrista species native to different biomes in the Brazilian state of Bahia, a major centre of diversity for the genus, was plotted onto an ITS-trnL-F-derived phylogeny of Chamaecrista. The bacteroids from most of the Chamaecrista species examined were enclosed in symbiosomes (SYM-type nodules), but those in arborescent species in the section Apoucouita, at the base of the genus, were enclosed in cell wall material containing homogalacturonan (HG) and cellulose (FT-type nodules). Most symbionts were Bradyrhizobium genotypes grouped according to the growth habits of their hosts, but the tree, C. eitenorum, was nodulated by Paraburkholderia. Chamaecrista has a range of growth habits that allow it to occupy several different biomes and to co-evolve with a wide range of (mainly) bradyrhizobial symbionts. FTs represent a less intimate symbiosis linked with nodulation losses, so the evolution of SYM-type nodules by most Chamaecrista species may have (i) aided the genus-wide retention of nodulation, and (ii) assisted in its rapid speciation and radiation out of the rainforest into more diverse and challenging habitats.
Relationship between clinical-epidemiological parameters and outcomes of patients with COVID-19 admitted to the intensive care unit: a report from a Brazilian hospital Maisah Meyhr D’Carmo Sodré, Uener Ribeiro dos Santos, Heitor Portella Povoas, Júlio Lenin Guzmán, Caroline Junqueira, et al. Frontiers in Public Health, 2023 BackgroundPeople in low-income countries, especially those with low socio-economic conditions, are likelier to test positive for SARS-CoV-2. The unequal conditions of public health systems also increase the infection rate and make early identification and treatment of at-risk patients difficult. Here, we aimed to characterize the epidemiological profile of COVID-19 patients in intensive care and identify laboratory and clinical markers associated with death.Materials and methodsWe conducted an observational, descriptive, and cross-sectional study in a reference hospital for COVID-19 treatment in the Southern Region of Bahia State, in Brazil, to evaluate the epidemiological, clinical, and laboratory characteristics of COVID-19 patients admitted to the intensive care unit (ICU). Additionally, we used the area under the curve (AUC) to classify survivors and non-survivors and a multivariate logistic regression analysis to assess factors associated with death. Data was collected from the hospital databases between April 2020 and July 2021.ResultsThe use of bladder catheters (OR 79.30; p < 0.0001) and central venous catheters (OR, 45.12; p < 0.0001) were the main factors associated with death in ICU COVID-19 patients. Additionally, the number of non-survivors increased with age (p < 0.0001) and prolonged ICU stay (p < 0.0001). Besides, SAPS3 presents a higher sensibility (77.9%) and specificity (63.1%) to discriminate between survivors and non-survivor with an AUC of 0.79 (p < 0.0001).ConclusionWe suggest that multi-laboratory parameters can predict patient prognosis and guide healthcare teams toward more assertive clinical management, better resource allocation, and improved survival of COVID-19 patients admitted to the ICU.
The innovation of the symbiosome has enhanced the evolutionary stability of nitrogen fixation in legumes Sergio M. de Faria, Jens J. Ringelberg, Eduardo Gross, Erik J. M. Koenen, Domingos Cardoso, et al. New Phytologist, 2022 Summary Nitrogen‐fixing symbiosis is globally important in ecosystem functioning and agriculture, yet the evolutionary history of nodulation remains the focus of considerable debate. Recent evidence suggesting a single origin of nodulation followed by massive parallel evolutionary losses raises questions about why a few lineages in the N2‐fixing clade retained nodulation and diversified as stable nodulators, while most did not. Within legumes, nodulation is restricted to the two most diverse subfamilies, Papilionoideae and Caesalpinioideae, which show stable retention of nodulation across their core clades. We characterize two nodule anatomy types across 128 species in 56 of the 152 genera of the legume subfamily Caesalpinioideae: fixation thread nodules (FTs), where nitrogen‐fixing bacteroids are retained within the apoplast in modified infection threads, and symbiosomes, where rhizobia are symplastically internalized in the host cell cytoplasm within membrane‐bound symbiosomes (SYMs). Using a robust phylogenomic tree based on 997 genes from 147 Caesalpinioideae genera, we show that losses of nodulation are more prevalent in lineages with FTs than those with SYMs. We propose that evolution of the symbiosome allows for a more intimate and enduring symbiosis through tighter compartmentalization of their rhizobial microsymbionts, resulting in greater evolutionary stability of nodulation across this species‐rich pantropical legume clade.
Growth, leaf gas exchange and mycorrhizal colonization of three medicinal species submitted to different irradiance levels Viviane Maria Barazetti, Eduardo Gross, George Andrade Sodré, Ândrea Carla Dalmolin, Larissa Corrêa do Bomfim Costa, et al. Ciencia Rural, 2022 This study o evaluated growth, leaf gas exchange and arbuscular mycorrhizal fungi root colonization in three medicinal plant species under different irradiance intensities. Fridericia chica (Bonpl.) L.G.Lohmann, Mikania laevigata Sch.Bip. ex Baker and Varronia curassavica Jacq. were propagated by cutting and cultivated for 120 days in artificially shaded environments using black shade-type screens, obtaining four irradiance levels: 100%, 70%, 50% and 30%. The experimental design was completely randomized in a 3 x 4 factorial scheme (three plant species and four irradiation levels) with seven replicates. The three medicinal species showed higher liquid assimilation, mass growth and arbuscular mycorrhizal fungi root colonization rates when exposed to environments with 70% light availability. In relation to physiological responses, V. curassavica presented higher photosynthetic rate, stomatal conductance and transpiration when submitted to 70% irradiance, being able to be cultivated in more open environments with higher irradiation levels. Conversely F. chica and M. laevigata presented shade tolerance characteristics. At the initial growth phase, the results obtained can be used as indicators to recommend the ideal cultivation environment for these species in agroforestry systems.
Substrate and quality mangosteen seedlings Gedeon Almeida Gomes Júnior, Rafaela Alves Pereira, Danillo José dos Santos, George Andrade Sodré, Eduardo Gross Revista Brasileira De Fruticultura, 2019