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1.
Plants (Basel) ; 13(12)2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38931099

RESUMO

Water deficiency has been recognized as a major abiotic stress that causes losses in maize crops around the world. The maize crop is very important due to the range of products that are derived from this plant. A potential way to reduce the damages caused by water deficiency in maize crops is through the association with plant growth-promoting bacteria (PGPB) and arbuscular mycorrhizal fungi (AMF). To define the mechanisms developed by associative PGPB and AMF in maize that are involved in protection against moderate drought (MD), this study evaluated the biometrical, anatomical, biochemical, and physiological parameters of maize grown under MD and inoculated with different PGPB (Azospirillum brasilense strain Ab-V5 and Bacillus sp. strain ZK) and with AMF. The relative water content did not change in the treatments. The association with ZK increased the shoot:total ratio, total dry weight, maximum quantum yield of photosystem II, vascular cylinder thickness, and vascular cylinder area. The Ab-V5 inoculation led to an increment in root dry weight, the area of metaxylem vessel elements, and nitrate reductase activity. The AMF association did not lead to changes in the measured parameters. The results indicate that the association with PGPB is a relevant alternative to contribute to reducing losses in maize crops under drought. However, AMF is not indicated for this crop under drought.

2.
Planta ; 260(1): 31, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888604

RESUMO

Deforestation of Atlantic Forest has caused prolonged drought events in the last decades. The need for reforestation is growing, and the development of native seedlings that are more tolerant to drought stress is necessary. A biotechnological tool that improves plant tolerance is the use of plant growth-promoting bacteria (PGPB) as inoculants. Two species of PGPB were inoculated in drought-stressed seedlings of two neotropical tree species that have been used in environmental restoration programs: Cecropia pachystachya and Cariniana estrellensis. Biometrical, physiological, and metabolomic parameters from carbon and nitrogen pathways were evaluated. We found that the PGPB positively influenced photosynthesis and growth parameters in both trees under drought. The enzymes activities, the tricarboxylic acid cycle intermediates, the amino acids, and protein contents were also influenced by the PGPB treatments. The results allowed us to find the specific composition of secondary metabolites of each plant species. This study provides evidence that there is not a single mechanism involved in drought tolerance and that the inoculation with PGPB promotes a broad-spectrum tolerance response in Neotropical trees. The inoculation with PGPB appears as an important strategy to improve drought tolerance in Atlantic Forest native trees and enhance environmental restoration programs' success. MAIN CONCLUSION: The association with plant growth-promoting bacteria improved the tolerance to drought in Neotropical trees through biochemical, physiological, and biometrical parameters. This can enhance the success of forest restoration programs.


Assuntos
Carbono , Secas , Metabolômica , Nitrogênio , Folhas de Planta , Árvores , Carbono/metabolismo , Nitrogênio/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Árvores/microbiologia , Árvores/metabolismo , Árvores/fisiologia , Cecropia/metabolismo , Cecropia/fisiologia , Fotossíntese , Estresse Fisiológico , Bactérias/metabolismo , Plântula/microbiologia , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Plântula/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-38765519

RESUMO

•The risk of venous thromboembolism (VTE) is not increased in women using long-acting reversible contraceptive methods (LARCs) with progestogens. •Oral contraceptives with levonorgestrel or norgestimate confer half the risk of VTE compared to oral contraceptives containing desogestrel, gestodene or drospirenone. •Progestogen-only pills do not confer an increased risk of VTE. •Women using transdermal contraceptive patches and combined oral contraceptives (COCs) are at an approximately eight times greater risk of VTE than non-users of hormonal contraceptives (HCs), corresponding to 9.7 events per 10,000 women/years. •Vaginal rings increase the risk of VTE by 6.5 times compared to not using HC, corresponding to 7.8 events per 10,000 women/years. •Several studies have demonstrated an increased risk of VTE in transgender individuals receiving hormone therapy (HT). •Hormone therapy during menopause increases the risk of VTE by approximately two times, and this risk is increased by obesity, thrombophilia, age over 60 years, surgery and immobilization. •The route of estrogen administration, the dosage and type of progestogen associated with estrogen may affect the risk of VTE in the climacteric. •Combined estrogen-progesterone therapy increases the risk of VTE compared to estrogen monotherapy. •Postmenopausal HT increases the risk of thrombosis at atypical sites.


Assuntos
Tromboembolia Venosa , Feminino , Humanos , Contraceptivos Hormonais/efeitos adversos , Contraceptivos Hormonais/administração & dosagem , Medição de Risco , Fatores de Risco , Tromboembolia Venosa/induzido quimicamente , Tromboembolia Venosa/etiologia
4.
Org Lett ; 26(4): 860-865, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38252019

RESUMO

ß-Amidated carboxylic acids, or succinamic acid derivatives, constitute a valuable chemical scaffold with broad applications in pharmaceuticals, agrochemicals, and polymer sciences. Herein, we report a redox-neutral multicomponent reaction for the synthesis of succinamic acid derivatives in good yields. This protocol involves styrene, CO2 and 1,4-carbamoyl-dihydropyridine as radical precursors. The method exhibits a broad substrate scope under mild reaction conditions, including late-stage functionalization. Moreover, by employing 13CO2, the method enables the synthesis of labeled 1,2-dicarboxylic compounds.

5.
Mol Ecol Resour ; 24(1): e13889, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38010882

RESUMO

Thiotrophic symbioses between sulphur-oxidizing bacteria and various unicellular and metazoan eukaryotes are widespread in reducing marine environments. The giant colonial ciliate Zoothamnium niveum, however, is the only host of thioautotrophic symbionts that has been cultivated along with its symbiont, the vertically transmitted ectosymbiont Candidatus Thiobius zoothamnicola (short Thiobius). Because theoretical predictions posit a smaller genome in vertically transmitted endosymbionts compared to free-living relatives, we investigated whether this is true also for an ectosymbiont. We used metagenomics to recover the high-quality draft genome of this bacterial symbiont. For comparison we have also sequenced a closely related free-living cultured but not formally described strain Milos ODIII6 (short ODIII6). We then performed comparative genomics to assess the functional capabilities at gene, metabolic pathway and trait level. 16S rRNA gene trees and average amino acid identity confirmed the close phylogenetic relationship of both bacteria. Indeed, Thiobius has about a third smaller genome than its free-living relative ODIII6, with reduced metabolic capabilities and fewer functional traits. The functional capabilities of Thiobius were a subset of those of the more versatile ODIII6, which possessed additional genes for oxygen, sulphur and hydrogen utilization and for the acquisition of phosphorus illustrating features that may be adaptive for the unstable environmental conditions at hydrothermal vents. In contrast, Thiobius possesses genes potentially enabling it to utilize lactate and acetate heterotrophically, compounds that may be provided as byproducts by the host. The present study illustrates the effect of strict host-dependence of a bacterial ectosymbiont on genome evolution and host adaptation.


Assuntos
Bactérias , Genômica , Animais , Filogenia , RNA Ribossômico 16S/genética , Simbiose , Enxofre/metabolismo
6.
BMC Genomics ; 24(1): 711, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38001438

RESUMO

BACKGROUND: Bryozoans are mostly sessile aquatic colonial invertebrates belonging to the clade Lophotrochozoa, which unites many protostome bilaterian phyla such as molluscs, annelids and brachiopods. While Hox and ParaHox genes have been extensively studied in various lophotrochozoan lineages, investigations on Hox and ParaHox gene complements in bryozoans are scarce. RESULTS: Herein, we present the most comprehensive survey of Hox and ParaHox gene complements in bryozoans using four genomes and 35 transcriptomes representing all bryozoan clades: Cheilostomata, Ctenostomata, Cyclostomata and Phylactolaemata. Using similarity searches, phylogenetic analyses and detailed manual curation, we have identified five Hox genes in bryozoans (pb, Dfd, Lox5, Lox4 and Post2) and one ParaHox gene (Cdx). Interestingly, we observed lineage-specific duplication of certain Hox and ParaHox genes (Dfd, Lox5 and Cdx) in some bryozoan lineages. CONCLUSIONS: The bryozoan Hox cluster does not retain the ancestral lophotrochozoan condition but appears relatively simple (includes only five genes) and broken into two genomic regions, characterized by the loss and duplication of serval genes. Importantly, bryozoans share the lack of two Hox genes (Post1 and Scr) with their proposed sister-taxon, Phoronida, which suggests that those genes were missing in the most common ancestor of bryozoans and phoronids.


Assuntos
Proteínas de Homeodomínio , Transcriptoma , Animais , Filogenia , Proteínas de Homeodomínio/genética , Invertebrados/genética , Genes Homeobox , Genômica
7.
Mem Inst Oswaldo Cruz ; 118: e220259, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37531506

RESUMO

BACKGROUND: Chikungunya is a mosquito-borne virus that has been causing large outbreaks in the Americas since 2014. In Brazil, Asian-Caribbean (AC) and East-Central-South-African (ECSA) genotypes have been detected and lead to large outbreaks in several Brazilian states. In Rio Grande do Sul (RS), the southernmost state of Brazil, the first cases were reported in 2016. OBJECTIVES AND METHODS: We employed genome sequencing and epidemiological investigation to characterise the Chikungunya fever (CHIKF) burden in RS between 2017-2021. FINDINGS: We detected an increasing CHIKF burden linked to travel associated introductions and communitary transmission of distinct lineages of the ECSA genotype during this period. MAIN CONCLUSIONS: Until 2020, CHIKV introductions were most travel associated and transmission was limited. Then, in 2021, the largest outbreak occurred in the state associated with the introduction of a new ECSA lineage. CHIKV outbreaks are likely to occur in the near future due to abundant competent vectors and a susceptible population, exposing more than 11 million inhabitants to an increasing infection risk.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Vírus Chikungunya/genética , Brasil/epidemiologia , Viagem , Filogenia , Mosquitos Vetores , Surtos de Doenças , Genótipo
8.
BMC Microbiol ; 23(1): 184, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438698

RESUMO

BACKGROUND: The release of organic acids (OAs) is considered the main mechanism used by phosphate-solubilizing bacteria (PSB) to dissolve inorganic phosphate in soil. Nevertheless, little is known about the effect of individual OAs produced by a particular PSB in a soil-plant system. For these reasons, the present work aimed at investigating the effect of Enterobacter sp. strain 15S and the exogenous application of its OAs on (i) the solubilization of tricalcium phosphate (TCP), (ii) plant growth and (iii) P nutrition of cucumber. To this purpose two independent experiments have been performed. RESULTS: In the first experiment, carried out in vitro, the phosphate solubilizing activity of Enterobacter 15S was associated with the release of citric, fumaric, ketoglutaric, malic, and oxalic acids. In the second experiment, cucumber plants were grown in a Leonard jar system consisting of a nutrient solution supplemented with the OAs previously identified in Enterobacter 15S (jar's base) and a substrate supplemented with the insoluble TCP where cucumber plants were grown (jar's top). The use of Enterobacter 15S and its secreted OAs proved to be efficient in the in situ TCP solubilization. In particular, the enhancement of the morpho-physiological traits of P-starved cucumber plants was evident when treated with Enterobacter 15S, oxalate, or citrate. The highest accumulation of P in roots and shoots induced by such treatments further corroborated this hypothesis. CONCLUSION: In our study, the results presented suggest that organic acids released by Enterobacter 15S as well as the bacterium itself can enhance the P-acquisition by cucumber plants.


Assuntos
Cucumis sativus , Fosfatos de Cálcio , Fosfatos , Compostos Orgânicos , Ácido Cítrico , Enterobacter , Oxalatos
9.
Mem. Inst. Oswaldo Cruz ; 118: e220259, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1448699

RESUMO

BACKGROUND Chikungunya is a mosquito-borne virus that has been causing large outbreaks in the Americas since 2014. In Brazil, Asian-Caribbean (AC) and East-Central-South-African (ECSA) genotypes have been detected and lead to large outbreaks in several Brazilian states. In Rio Grande do Sul (RS), the southernmost state of Brazil, the first cases were reported in 2016. OBJECTIVES AND METHODS We employed genome sequencing and epidemiological investigation to characterise the Chikungunya fever (CHIKF) burden in RS between 2017-2021. FINDINGS We detected an increasing CHIKF burden linked to travel associated introductions and communitary transmission of distinct lineages of the ECSA genotype during this period. MAIN CONCLUSIONS Until 2020, CHIKV introductions were most travel associated and transmission was limited. Then, in 2021, the largest outbreak occurred in the state associated with the introduction of a new ECSA lineage. CHIKV outbreaks are likely to occur in the near future due to abundant competent vectors and a susceptible population, exposing more than 11 million inhabitants to an increasing infection risk.

10.
Clin Appl Thromb Hemost ; 28: 10760296221132556, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36474344

RESUMO

Direct oral anticoagulants (DOACs) for venous thromboembolism (VTE) prevention after major gynecological cancer surgery might be an alternative to parenteral low-molecular-weight heparin (LMWH). Patients undergoing major gynecological cancer surgery were randomized at hospital discharge to receive rivaroxaban 10 mg once daily or enoxaparin 40 mg once daily for 30 days. The primary efficacy outcome was a combination of symptomatic VTE and VTE-related death or asymptomatic VTE at day 30. The primary safety outcome was the incidence of major or clinically relevant nonmajor bleeding. Two hundred and twenty-eight patients were enrolled and randomly assigned to receive rivaroxaban (n = 114)or enoxaparin (n = 114). The trial was stopped due to a lower-than-expected event rate. The primary efficacy outcome occurred in 3.51% of patients assigned to rivaroxaban and in 4.39% of patients assigned to enoxaparin (relative risk 0.80, 95% CI 0.22 to 2.90; p = 0.7344). Patients assigned to rivaroxaban had no primary bleeding event, and 3 patients (2.63%) in the enoxaparin group had a major or CRNM bleeding event (hazard ratio, 0.14; 95% CI, 0.007 to 2.73; P = 0.1963). In patients undergoing major gynecological cancer surgery, thromboprophylaxis with rivaroxaban 10 mg daily for 30 days had similar rates of thrombotic and bleeding events compared to parenteral enoxaparin 40 mg daily. While the power is limited due to not reaching the intended sample size, our results support the hypothesis that DOACs might be an attractive alternative strategy to LMWH to prevent VTE in this high-risk population.


Assuntos
Neoplasias Pélvicas , Tromboembolia Venosa , Humanos , Enoxaparina/efeitos adversos , Rivaroxabana/uso terapêutico , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Anticoagulantes/uso terapêutico , Heparina de Baixo Peso Molecular
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