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1.
Plant J ; 116(6): 1842-1855, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37665679

RESUMO

Perennial monocarpic mass flowering represents as a key developmental innovation in flowering time diversity in several biological and economical essential families, such as the woody bamboos and the shrubby Strobilanthes. However, molecular and genetic mechanisms underlying this important biodiversity remain poorly investigated. Here, we generated a full-length transcriptome resource incorporated into the BlueOmics database (http://blueomics.iflora.cn) for two Strobilanthes species, which feature contrasting flowering time behaviors. Using about 112 and 104 Gb Iso-seq reads together with ~185 and ~75 Gb strand-specific RNA seq data, we annotated 80 971 and 79 985 non-redundant full-length transcripts for the perennial polycarpic Strobilanthes tetrasperma and the perennial monocarpic Strobilanthes biocullata, respectively. In S. tetrasperma, we identified 8794 transcripts showing spatiotemporal expression in nine tissues. In leaves and shoot apical meristems at two developmental stages, 977 and 1121 transcripts were differentially accumulated in S. tetrasperma and S. biocullata, respectively. Interestingly, among the 33 transcription factors showing differential expression in S. tetrasperma but without differential expression in S. biocullata, three were involved potentially in the photoperiod and circadian-clock pathway of flowering time regulation (FAR1 RELATED SEQUENCE 12, FRS12; NUCLEAR FACTOR Y A1, NFYA1; PSEUDO-RESPONSE REGULATOR 5, PRR5), hence provides an important clue in deciphering the flowering diversity mechanisms. Our data serve as a key resource for further dissection of molecular and genetic mechanisms underpinning key biological innovations, here, the perennial monocarpic mass flowering.


Assuntos
Flores , Transcriptoma , Humanos , Transcriptoma/genética , Flores/genética , Flores/metabolismo , Perfilação da Expressão Gênica , Folhas de Planta/metabolismo , RNA-Seq , Regulação da Expressão Gênica de Plantas/genética
2.
Mol Biol Evol ; 40(1)2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36477354

RESUMO

Self-incompatibility (SI) is a genetic mechanism of hermaphroditic plants to prevent inbreeding after self-pollination. Allogamous Poaceae species exhibit a unique gametophytic SI system controlled by two multi-allelic and independent loci, S and Z. Despite intense research efforts in the last decades, the genes that determine the initial recognition mechanism are yet to be identified. Here, we report the fine-mapping of the Z-locus in perennial ryegrass (Lolium perenne L.) and provide evidence that the pollen and stigma components are determined by two genes encoding DUF247 domain proteins (ZDUF247-I and ZDUF247-II) and the gene sZ, respectively. The pollen and stigma determinants are located side-by-side and were genetically linked in 10,245 individuals of two independent mapping populations segregating for Z. Moreover, they exhibited high allelic diversity as well as tissue-specific gene expression, matching the expected characteristics of SI determinants known from other systems. Revisiting the S-locus using the latest high-quality whole-genome assemblies revealed a similar gene composition and structure as found for Z, supporting the hypothesis of a duplicated origin of the two-locus SI system of grasses. Ultimately, comparative genomic analyses across a wide range of self-compatible and self-incompatible Poaceae species revealed that the absence of a functional copy of at least one of the six putative SI determinants is accompanied by a self-compatible phenotype. Our study provides new insights into the origin and evolution of the unique gametophytic SI system in one of the largest and economically most important plant families.


Assuntos
Lolium , Poaceae , Poaceae/genética , Lolium/genética , Pólen/genética , Plantas , Genômica
3.
Plant Biotechnol J ; 22(3): 678-697, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37902192

RESUMO

Abiotic stresses such as salinity, heat and drought seriously impair plant growth and development, causing a significant loss in crop yield and ornamental value. Biotechnology approaches manipulating specific genes prove to be effective strategies in crop trait modification. The Arabidopsis vacuolar pyrophosphatase gene AVP1, the rice SUMO E3 ligase gene OsSIZ1 and the cyanobacterium flavodoxin gene Fld have previously been implicated in regulating plant stress responses and conferring enhanced tolerance to different abiotic stresses when individually overexpressed in various plant species. We have explored the feasibility of combining multiple favourable traits brought by individual genes to acquire superior plant performance. To this end, we have simultaneously introduced AVP1, OsSIZ1 and Fld in creeping bentgrass. Transgenic (TG) plants overexpressing these three genes performed significantly better than wild type controls and the TGs expressing individual genes under both normal and various abiotic stress conditions, exhibited significantly enhanced plant growth and tolerance to drought, salinity and heat stresses as well as nitrogen and phosphate starvation, which were associated with altered physiological and biochemical characteristics and delicately fine-tuned expression of genes involved in plant stress responses. Our results suggest that AVP1, OsSIZ1 and Fld function synergistically to regulate plant development and plant stress response, leading to superior overall performance under both normal and adverse environments. The information obtained provides new insights into gene stacking as an effective approach for plant genetic engineering. A similar strategy can be extended for the use of other beneficial genes in various crop species for trait modifications, enhancing agricultural production.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Estresse Fisiológico/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Desenvolvimento Vegetal , Regulação da Expressão Gênica de Plantas/genética , Secas , Proteínas de Plantas/genética
4.
Plant Biotechnol J ; 22(9): 2541-2557, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38715250

RESUMO

MicroRNA169 (miR169) has been implicated in multi-stress regulation in annual species such as Arabidopsis, maize and rice. However, there is a lack of experimental functional and mechanistic studies of miR169 in plants, especially in perennial species, and its impact on plant growth and development remains unexplored. Creeping bentgrass (Agrostis stolonifera L.) is a C3 cool-season perennial turfgrass of significant environmental and economic importance. In this study, we generated both miR169 overexpression and knockdown transgenic creeping bentgrass lines. We found that miR169 acts as a positive regulator in abiotic stress responses but is negatively associated with plant growth and development, playing multiple critical roles in the growth and environmental adaptation of creeping bentgrass. These roles include differentiated spatial hormone accumulation patterns associated with growth and stress accommodation, elevated antioxidant activity that alleviates oxidative damage induced by stress, ion-channelling membrane components for maintaining homeostasis under saline conditions, and potential cross-talks with stress-regulating transcription factors such as AsHsfA and AsWRKYs. Our results unravel the role of miR169 in modulating plant development and stress responses in perennial grass species. This underlines the potential of manipulating miR169 to generate crop cultivars with desirable traits to meet diverse agricultural demands.


Assuntos
Agrostis , Regulação da Expressão Gênica de Plantas , MicroRNAs , Estresse Fisiológico , Agrostis/genética , Agrostis/crescimento & desenvolvimento , Agrostis/fisiologia , Agrostis/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Plantas Geneticamente Modificadas/genética , RNA de Plantas/genética , RNA de Plantas/metabolismo
5.
New Phytol ; 244(1): 292-306, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39135384

RESUMO

Spring regrowth in temperate perennials relies on renewal buds, which form a key component in the shoot growth cycle. Still, we possess almost no information on these renewal buds, which is becoming more pressing with the current climate change. Most existing studies concentrated on easy-to-study aboveground buds of woody plants, whose morphology has largely been linked to frost protection. It is not clear to what extent these findings apply also to herbaceous species. We therefore examined protective traits and preformation of winter renewal buds in 379 species of temperate herbs, and tested how these traits are distributed across the phylogeny and related to other bud bank and whole-plant traits. We identified a major gradient from few, large, highly preformed, scale-covered buds associated with larger belowground storage organs deep in the soil, to small, numerous, less preformed, and naked buds near the soil surface. Belowground renewal buds of temperate herbs show several distinct strategies for winter survival and spring regrowth that might affect their response to changing winter and early spring conditions. Renewal bud traits are driven not only by frost protection but also by protection of the apical meristem from mechanical disturbance in the soil.


Assuntos
Filogenia , Estações do Ano , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Biodiversidade , Especificidade da Espécie , Plantas
6.
Plant Cell Environ ; 47(3): 976-991, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38164069

RESUMO

Mosses are vital components of ecosystems, exhibiting remarkable adaptability across diverse habitats from deserts to polar ice caps. Sanionia uncinata (Hedw.) Loeske, a dominant Antarctic moss survives extreme environmental condition through perennial lifecycles involving growth and dormancy alternation. This study explores genetic controls and molecular mechanisms enabling S. uncinata to cope with seasonality of the Antarctic environment. We analysed the seasonal transcriptome dynamics of S. uncinata collected monthly from February 2015 to January 2016 in King George Island, Antarctica. Findings indicate that genes involved in plant growth were predominantly upregulated in Antarctic summer, while those associated with protein synthesis and cell cycle showed marked expression during the winter-to-summer transition. Genes implicated in cellular stress and abscisic acid signalling were highly expressed in winter. Further, validation included a comparison of the Antarctic field transcriptome data with controlled environment simulation of Antarctic summer and winter temperatures, which revealed consistent gene expression patterns in both datasets. This proposes a seasonal gene regulatory model of S. uncinate to understand moss adaptation to extreme environments. Additionally, this data set is a valuable resource for predicting genetic responses to climatic fluctuations, enhancing our knowledge of Antarctic flora's resilience to global climate change.


Assuntos
Briófitas , Briófitas/genética , Ecossistema , Regiões Antárticas , Neve , Ambientes Extremos , Perfilação da Expressão Gênica
7.
Plant Cell Environ ; 47(6): 2274-2287, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38488789

RESUMO

The 18O enrichment (Δ18O) of cellulose (Δ18OCel) is recognized as a unique archive of past climate and plant function. However, there is still uncertainty regarding the proportion of oxygen in cellulose (pex) that exchanges post-photosynthetically with medium water of cellulose synthesis. Particularly, recent research with C3 grasses demonstrated that the Δ18O of leaf sucrose (Δ18OSuc, the parent substrate for cellulose synthesis) can be much higher than predicted from daytime Δ18O of leaf water (Δ18OLW), which could alter conclusions on photosynthetic versus post-photosynthetic effects on Δ18OCel via pex. Here, we assessed pex in leaves of perennial ryegrass (Lolium perenne) grown at different atmospheric relative humidity (RH) and CO2 levels, by determinations of Δ18OCel in leaves, Δ18OLGDZW (the Δ18O of water in the leaf growth-and-differentiation zone) and both Δ18OSuc and Δ18OLW (adjusted for εbio, the biosynthetic fractionation between water and carbohydrates) as alternative proxies for the substrate for cellulose synthesis. Δ18OLGDZW was always close to irrigation water, and pex was similar (0.53 ± 0.02 SE) across environments when determinations were based on Δ18OSuc. Conversely, pex was erroneously and variably underestimated (range 0.02-0.44) when based on Δ18OLW. The photosynthetic signal fraction in Δ18OCel is much more constant than hitherto assumed, encouraging leaf physiological reconstructions.


Assuntos
Dióxido de Carbono , Celulose , Umidade , Isótopos de Oxigênio , Folhas de Planta , Sacarose , Folhas de Planta/metabolismo , Celulose/metabolismo , Dióxido de Carbono/metabolismo , Sacarose/metabolismo , Isótopos de Oxigênio/metabolismo , Lolium/metabolismo , Lolium/crescimento & desenvolvimento , Lolium/fisiologia , Atmosfera , Fotossíntese , Água/metabolismo
8.
Int Arch Allergy Immunol ; 185(3): 218-227, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38052187

RESUMO

INTRODUCTION: Notably, few studies have evaluated the recent changes in the prevalence of allergic diseases in young adults. Studies examining the risk of allergy in two populations with similar social backgrounds, other than the region in which they live, are rare. METHODS: First-year students from Hokkaido University were enrolled in this study between 2011 and 2019. A questionnaire survey was conducted to determine the annual prevalence of current wheeze, seasonal allergic rhinitis (SAR), and perennial allergic rhinitis (PAR) in nonsmoking young adults. Trends in the presence of these disease conditions were evaluated based on their hometowns (Hokkaido and outside Hokkaido separately) due to the low prevalence of cedar pollen allergies in Hokkaido. The association between these disease conditions and body mass index (BMI) was also assessed. RESULTS: The prevalence of current wheeze and PAR food allergies did not change in both regions. SAR showed a significantly increasing trend; however, the prevalence of SAR was higher among those whose place of origin was not Hokkaido. Current wheeze was positively associated with obesity (p < 0.05), whereas the high prevalence of SAR was not associated with body weight. In contrast, a lean body type was significantly associated with a higher prevalence of PAR (p < 0.05). DISCUSSION/CONCLUSION: The prevalence of current wheeze was stable and that of PAR has decreased over the past 9 years. However, the prevalence of SAR in Hokkaido has been increasing in Japanese young adults. A differential association between current wheeze and BMI was observed when comparing PAR and SAR.


Assuntos
Hipersensibilidade , Rinite Alérgica Perene , Rinite Alérgica Sazonal , Humanos , Adulto Jovem , Prevalência , Hipersensibilidade/epidemiologia , Hipersensibilidade/complicações , Rinite Alérgica Sazonal/epidemiologia , Rinite Alérgica Perene/complicações , Obesidade/epidemiologia , Obesidade/complicações
9.
Ann Bot ; 134(1): 101-116, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38488820

RESUMO

BACKGROUND AND AIMS: Intra- and transgenerational plasticity may provide substantial phenotypic variation to cope with environmental change. Since assessing the unique contribution of the maternal environment to the offspring phenotype is challenging in perennial, outcrossing plants, little is known about the evolutionary and ecological implications of transgenerational plasticity and its persistence over the life cycle in these species. We evaluated how intra- and transgenerational plasticity interplay to shape the adaptive responses to drought in two perennial Mediterranean shrubs. METHODS: We used a novel common garden approach that reduced within-family genetic variation in both the maternal and offspring generations by growing the same maternal individual in two contrasting watering environments, well-watered and drought, in consecutive years. We then assessed phenotypic differences at the reproductive stage between offspring reciprocally grown in the same environments. KEY RESULTS: Maternal drought had an effect on offspring performance only in Helianthemum squamatum. Offspring of drought-stressed plants showed more inflorescences, less sclerophyllous leaves and higher growth rates in both watering conditions, and heavier seeds under drought, than offspring of well-watered maternal plants. Maternal drought also induced similar plasticity patterns across maternal families, showing a general increase in seed mass in response to offspring drought, a pattern not observed in the offspring of well-watered plants. In contrast, both species expressed immediate adaptive plasticity, and the magnitude of intragenerational plasticity was larger than the transgenerational plastic responses. CONCLUSIONS: Our results highlight that adaptive effects associated with maternal drought can persist beyond the seedling stage and provide evidence of species-level variation in the expression of transgenerational plasticity. Such differences between co-occurring Mediterranean species in the prevalence of this form of non-genetic inheritance may result in differential vulnerability to climate change.


Assuntos
Adaptação Fisiológica , Secas , Adaptação Fisiológica/genética , Fenótipo , Região do Mediterrâneo , Sementes/genética , Sementes/fisiologia , Sementes/crescimento & desenvolvimento , Variação Genética
10.
Ann Bot ; 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126169

RESUMO

BACKGROUND AND AIMS: Roots and rhizomes are critical for the adaptation of clonal plants to soil water gradients. Oryza longistaminata, a rhizomatous wild rice, is of particular interest for perennial rice breeding due to its resilience under abiotic stress conditions. While root responses to soil flooding are well-studied, rhizome responses to water gradients remain underexplored. We hypothesize that physiological integration of Oryza longistaminata mitigates heterogeneous water deficit stress through interconnected rhizomes, and both roots and rhizomes respond to contrasting water conditions. METHODS: We investigated the physiological integration between mother plants and ramets, measuring key photosynthetic parameters (photosynthetic and transpiration rate, and stomatal conductance) using an Infrared Gas Analyzer. Moreover, root and rhizome responses to three water regimes (flooding, well-watered, and water deficit) were examined by measuring radial water loss and apparent permeance to O2, along with histochemical and anatomical characterization. KEY RESULTS: Our experiment highlights the role of physiological integration via interconnected rhizomes in mitigating water deficit stress. Severing rhizome connections from mother plants or ramets exposed to water deficit conditions led to significant decreases in key photosynthetic parameters, underscoring the importance of rhizome connections in bidirectional stress mitigation. Additionally, O. longistaminata rhizomes exhibited constitutive suberized and lignified apoplastic barriers, while such barriers were induced in roots under water stress. Anatomically, both rhizomes and roots respond similarly to water gradients, showing thinner diameters under water deficit conditions and larger diameters under flooding conditions. CONCLUSION: Our findings indicate that physiological integration through interconnected rhizomes helps alleviate water deficit stress when either the mother plant or the ramet is experiencing water deficit, while the counterpart is in control conditions. Moreover, O. longistaminata can adapt to various soil water regimes by regulating anatomical and physiological traits of roots and rhizomes.

11.
Malar J ; 23(1): 157, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773567

RESUMO

BACKGROUND: Perennial malaria chemoprevention (PMC) aims to protect children at risk from severe malaria by the administration of anti-malarial drugs to children of defined ages throughout the year. Sulfadoxine-pyrimethamine (SP) has been widely used for chemoprevention in Africa and a child-friendly dispersible tablet formulation has recently become available. METHODS: This qualitative non-interventional observational study was conducted in Benin, Côte d'Ivoire, and Mozambique between February and June 2022. Prototype blister packs, dispensing boxes and job aids designed to support dispersible SP deployment for PMC were evaluated using focus group discussions (FGD) and semi-structured in-depth individual interviews (IDI) with health authorities, health personnel, community health workers (CHWs) and caregivers. The aim was to evaluate knowledge and perceptions of malaria and chemoprevention, test understanding of the tools and identify gaps in understanding, satisfaction, user-friendliness and acceptability, and assess the potential role of CHWs in PMC implementation. Interviews were transcribed and imported to ATLAS.ti for encoding and categorization. Thematic content analysis used deductive and inductive coding with cross-referencing of findings between countries and participants to enrich data interpretation. Continuous comparison across the IDI and FGD permitted iterative, collaborative development of materials. RESULTS: Overall, 106 participants completed IDIs and 70 contributed to FGDs. Malaria was widely recognised as the most common disease affecting children, and PMC was viewed as a positive intervention to support child health. The role of CHWs was perceived differently by the target groups, with caregivers appreciating their trusted status in the community, whereas health authorities preferred clinic-based deployment of PMC by health professionals. Empirical testing of the prototype blister packs, dispensing boxes and job aids highlighted the context-specific expectations of respondents, such as familiar situations and equipment, and identified areas of confusion or low acceptance. A key finding was the need for a clear product identity reflecting malaria. CONCLUSION: Simple modifications profoundly affected the perception of PMC and influenced acceptability. Iterative quantitative investigation resulted in PMC-specific materials suited to the local context and socio-cultural norms of the target population with the aim of increasing access to chemoprevention in children most at risk of severe malaria.


Assuntos
Antimaláricos , Quimioprevenção , Combinação de Medicamentos , Malária , Pirimetamina , Moçambique , Benin , Malária/prevenção & controle , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Quimioprevenção/métodos , Quimioprevenção/estatística & dados numéricos , Humanos , Côte d'Ivoire , Pirimetamina/administração & dosagem , Pirimetamina/uso terapêutico , Sulfadoxina/administração & dosagem , Sulfadoxina/uso terapêutico , Pré-Escolar , Feminino , Masculino , Embalagem de Medicamentos/métodos , Lactente , Criança , Adulto
12.
BMC Infect Dis ; 24(1): 1028, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327613

RESUMO

BACKGROUND: The World Health Organization 2022 malaria chemoprevention guidelines recommend providing a full course of antimalarial treatment at pre-defined intervals, regardless of malaria status to prevent illness among children resident in moderate to high perennial malaria transmission settings as perennial malaria chemoprevention (PMC) with sulfadoxine-pyrimethamine (SP). The dhps I431V mutation circulating in West Africa has unknown effect on SP protective efficacy. METHODS: This protocol is for a three-arm, parallel, double-blinded, placebo-controlled, randomised trial in Cameroon among children randomly assigned to one of three directly-observed treatment groups: (i) Group 1 (n = 450) receives daily artesunate (AS) placebo on days - 7 to -1, then active SP plus placebo amodiaquine (AQ) on day 0, and placebo AQ on days 1 and 2; (ii) Group 2 (n = 250) receives placebo AS on days - 7 to -1, then active SP and AQ on day 0, and active AQ on days 1 and 2; and (iii) Group 3 (n = 200) receives active AS on days - 7 to -1, then placebo SP on day 0 and placebo AQ on days 0 to 2. On days 0, 2, 5, 7, and thereafter weekly until day 28, children provide blood for thick smear slides. Dried blood spots are collected on the same days and weekly from day 28 to day 63 for quantitative polymerase chain reaction (qPCR) and genotype analyses. DISCUSSION: Our aim is to quantify the chemopreventive efficacy of SP, and SP plus AQ, and measure the effect of the parasite genotypes associated with SP resistance on parasite clearance and protection from infection when exposed to SP chemoprevention. We will report unblinded results including: (i) time-to-parasite clearance among SP and SP plus AQ recipients who were positive on day 0 by qPCR and followed to day 63; (ii) mean duration of SP and SP plus AQ protection against infection, and (iii) mean duration of symptom-free status among SP and SP plus AQ recipients who were parasite free on day 0 by qPCR. Our study is designed to compare the 28-day follow-up of the new WHO malaria chemoprevention efficacy study protocol with extended follow-up to day 63. TRIAL REGISTRATION: ClinicalTrials.gov NCT06173206; 15/12/2023.


Assuntos
Amodiaquina , Antimaláricos , Artesunato , Combinação de Medicamentos , Malária Falciparum , Plasmodium falciparum , Pirimetamina , Sulfadoxina , Humanos , Pirimetamina/uso terapêutico , Pirimetamina/administração & dosagem , Camarões , Sulfadoxina/uso terapêutico , Sulfadoxina/administração & dosagem , Malária Falciparum/prevenção & controle , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Antimaláricos/uso terapêutico , Antimaláricos/administração & dosagem , Pré-Escolar , Amodiaquina/uso terapêutico , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Método Duplo-Cego , Feminino , Masculino , Artesunato/uso terapêutico , Artemisininas/uso terapêutico , Artemisininas/administração & dosagem , Resultado do Tratamento , Quimioprevenção/métodos
13.
J Asthma ; : 1-8, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38884630

RESUMO

BACKGROUND: Eosinophil-derived neurotoxin (EDN) is an important biomarker of eosinophilic inflammation. METHODS: This study evaluated Montelukast treatment response according to EDN concentration in children with perennial allergic rhinitis (PAR). Fifty-two children with PAR were recruited and took a combination of Montelukast (5mg) and Levocetirizine (5mg) "Mont/Levo Group" or only Montelukast (5mg) "Mont Group" for 4 weeks. All caregivers were instructed to record rhinitis symptoms for 4 weeks. EDN was measured before and after treatment. RESULTS: Daytime nasal symptom scores (DNSS) significantly decreased in both the Mont/Levo (p = 0.0001; n = 20) and Mont Group (p < 0.0001; n = 20), but there were no significant differences between the two groups. EDN concentration also significantly decreased after treatment in both groups (p < 0.0001 and p < 0.001, respectively). For secondary analysis, children with a high initial EDN concentration (EDN ≥ 53 ng/mL) were placed in the "High EDN Group", while those with a lower initial EDN concentration (EDN < 53 ng/mL) were put in the "Low EDN Group". Both groups experienced significant reductions in DNSS after either treatment regimen (p < 0.0001 and p = 0.0027, respectively) but the High EDN Group had greater reductions. EDN concentrations in the High EDN Group decreased significantly from either treatment (p < 0.0001). CONCLUSION: We found that children with AR and a high serum EDN concentration may respond well to Montelukast treatment. A therapeutic strategy using EDN concentrations in patients with AR to evaluate therapeutic response may help improve quality of care.

14.
BMC Public Health ; 24(1): 2430, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243075

RESUMO

BACKGROUND: Perennial malaria chemoprevention (PMC) is a chemoprevention strategy endorsed by the World Health Organization (WHO) and is increasingly being adopted by National Malaria Programmes. PMC aims to reduce morbidity and mortality caused by malaria and anaemia in in young children through provision of antimalarial drugs at routine contact points with the local health system. This study aims to evaluate the impact of the programmatically-implemented country-tailored PMC programmes targeting children up to two years of age using sulfadoxine-pyrimethamine (SP) on the incidence of malaria and anaemia in children in Cameroon and Côte d'Ivoire. METHODS: We will assess the impact of PMC using passive and active monitoring of a prospective observational cohort of children up to 36 months of age at recruitment in selected study sites in Cameroon and Côte d'Ivoire. The primary and secondary outcomes include malaria, anaemia and malnutrition incidence. We will also conduct a time-series analysis of passively detected malaria and anaemia cases comparing the periods before and after PMC introduction. This study is powered to detect a 30% and 40% reduction of malaria incidence compared to the standard of care in Cameroon and Côte d'Ivoire, respectively. DISCUSSION: This multi-country study aims to provide evidence of the effectiveness of PMC targeting children in the first two years of life on malaria and anaemia and will provide important information to inform optimal operationalization and evaluation of this strategy. TRIAL REGISTRATION: Cameroon - NCT05889052; Côte d'Ivoire - NCT05856357.


Assuntos
Anemia , Antimaláricos , Quimioprevenção , Malária , Pirimetamina , Sulfadoxina , Humanos , Camarões/epidemiologia , Lactente , Côte d'Ivoire/epidemiologia , Estudos Prospectivos , Malária/prevenção & controle , Malária/epidemiologia , Antimaláricos/uso terapêutico , Pirimetamina/uso terapêutico , Pré-Escolar , Sulfadoxina/uso terapêutico , Anemia/prevenção & controle , Anemia/epidemiologia , Combinação de Medicamentos , Incidência , Feminino , Masculino
15.
J Dairy Sci ; 107(4): 2129-2142, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37939834

RESUMO

The objective of this study was to quantify the farm gate nitrogen (N) offset potential of perennial ryegrass (Lolium perenne L.; PRG) white clover (Trifolium repens L.; WC) swards by comparing the herbage and milk production from dairy farmlets that were simulations of full farming systems. A study was established where 120 cows were randomly assigned to 4 farmlets of 10.9 ha (stocking rate: 2.75 cow/ha), composed of 20 paddocks each. Cows were fed 526 kg of DM of concentrate on average each year. The 4 grazing treatments were PRG-only at 150 or 250 kg of N/ha and PRG-WC at 150 or 250 kg of N/ha. Cows remained in their treatment group for an entire grazing season and were re-randomized as they calved across treatments each year. As cows calved in the spring as standard practice in Ireland, they were rotationally grazed from early February both day and night (weather permitting) to mid-November, to a target postgrazing sward height of 4.0 cm. Mean sward WC content was 18.1% and 15.4% for the 150 and 250 kg of N/ha PRG-WC treatments, respectively over the 3-yr period. When WC was included, lowering the N rate did not reduce pregrazing yield, pregrazing height, or herbage removed, but those factors decreased significantly when WC was absent. Total annual herbage DM production was 13,771, 15,242, 14,721, and 15,667 kg of DM/ha for PRG-only swards receiving 150 or 250 kg of N/ha and PRG-WC swards receiving 150 or 250 kg of N/ha, respectively. In addition, when WC was present, compressed postgrazing sward heights were lower (4.10 vs. 4.21 cm) and herbage allowance (approximately 17 kg/cow feed allocation per cow per day) higher than the high-N control (+ 0.7 kg of DM/cow per day). There was a significant increase in milk production, both per cow and per hectare, when WC was included in PRG swards. Over the 3-yr study, cows grazing PRG-WC had greater milk (+304 kg) and milk solids (+31 kg of fat + protein) yields than cows grazing PRG-only swards. This significant increase in milk production suggests that the inclusion of WC in grazing systems can be effectively used to increase milk production per cow and per hectare and help offset nitrogen use. This result shows the potential to increase farm gate N use efficiency and reduce the N surplus compared with PRG-dominant sward grazing systems receiving 250 kg of N/ha, without negatively affecting milk solids yield or herbage production, thus increasing farm profit by €478/ha.


Assuntos
Lolium , Trifolium , Feminino , Bovinos , Animais , Leite/metabolismo , Lactação , Nitrogênio/metabolismo , Ração Animal/análise , Indústria de Laticínios , Estações do Ano , Medicago , Dieta/veterinária
16.
Plant Dis ; 108(7): 1982-1986, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38937876

RESUMO

Ganoderma boninense is a basidiomycete pathogen of African oil palm (Elaeis guineensis) and the causal agent of basal stem rot (BSR) disease, which is the most destructive fungal disease of oil palm in Southeast Asia. The disease is fatal for infected palms and can result in 50 to 80% losses in oil yields because of a reduction in productive life span and a yield decline of infected oil palms. In this study, G. boninense isolates collected from different locations and planting blocks with different palm ages were molecularly characterized using microsatellite genotyping. Results showed high pathogen genetic diversity (He = 0.67 to 0.74) among planting blocks and between oil palm estates. Two nearby planting blocks with similar planting ages (i.e., 1999 and 2001) had a similar percentage of BSR incidence (>20%) but showed distinct Ganoderma genetic structure as detected using STRUCTURE. Similar results were obtained from another trial site where planting blocks differing in planting age but located only less than 1 km apart showed a diverse genetic background. The pathogen genetic admixture of the oldest planting (>30% BSR incidence) differed significantly from the younger planting (1.8 to 2.8% BSR incidence, breeding trial block), suggesting that the host-pathogen genotype interaction may impact the Ganoderma genetic variation over time. The genetic structure of G. boninense, as revealed in this study, implies positive selection resulting from the pathogen genetic variation, host-pathogen interaction, and possible introductions of novel genetic variants (through spores) from adjacent plantings. These findings offer new insights into the genetic changes of G. boninense over time. The information is essential to design disease management strategies and breeding for BSR resistance in oil palm.


Assuntos
Arecaceae , Ganoderma , Variação Genética , Doenças das Plantas , Ganoderma/genética , Arecaceae/microbiologia , Doenças das Plantas/microbiologia , Malásia , Repetições de Microssatélites/genética , Genótipo
17.
J Environ Manage ; 368: 122220, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39154386

RESUMO

In the face of the global biodiversity decline, ecological restoration measures to actively enhance urban biodiversity and options for biodiversity-friendly greenspace management are high on the agenda of many governments and city administrations. This review aims to summarize and advance the current knowledge on urban grassland restoration by synthesizing research findings on restoration approaches and biodiversity-friendly management measures globally. Indeed, we found restoration approaches to be generally effective in increasing biodiversity; yet, there were variations in the outcomes due to the difference in soil disturbance methods, management regimes, the set of species introduced to a site, and the specific local setting. Based on the reviewed studies, we formulated recommendations for maximizing restoration success of urban grasslands through: i) creating a network of heterogeneous urban greenspaces and enhancing connectivity between them; ii) maintaining the spontaneous vegetation in vacant lots and wasteland sites that can provide habitats for various invertebrate species; iii) evaluating actual soil conditions, soil seed bank, and seed rain before restoration efforts take place since these seed sources could considerably affect the restoration outcomes, iv) preserving nutrient-poor conditions in urban greenspaces instead of introducing nutrient-rich topsoil; v) shifting to less intensive, biodiversity-friendly management in urban greenspaces by reducing mowing frequency and avoiding the use of chemicals; and vi) utilizing native dry grassland species for climate adaptation without irrigation. We further identified knowledge gaps regarding i) city-scale and regional-scale effects of restoration, ii) effects of interventions on multiple taxa and multiple ecosystem services, iii) restoration in small versus mega-cities, and iv) in the global south. These gaps should be addressed in future studies for making general guidelines for urban grassland restoration broadly applicable.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Pradaria , Conservação dos Recursos Naturais/métodos , Ecossistema , Solo
18.
J Environ Manage ; 357: 120739, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38552522

RESUMO

Knowledge of freeze-thaw-induced carbon (C) and nitrogen (N) cycling and concomitant nitrous oxide (N2O) and carbon dioxide (CO2) emissions in perennial bioenergy crops is crucial to understanding the contribution of these crops in mitigating climate change through reduced greenhouse gas (GHG) emissions. In this study, a 49-day laboratory incubation experiment was conducted to compare the impact of freeze-thaw cycles on N2O and CO2 emissions in different perennial bioenergy crops [miscanthus (Miscanthus giganteus L.), switchgrass (Panicum virgatum L.), and willow (Salix miyabeana L.)] to a successional site and to understand the processes controlling the N2O and CO2 emissions in these crops. The results showed that freeze-thaw cycles caused a decline in dissolved organic C (DOC) and dissolved inorganic N (DIN) concentrations but enhanced the dissolved organic N (DON) and nitrate (NO3-). Although, freeze-thaw decreased water stable soil aggregates in all the bioenergy crops and successional site, this did not have any significant impact on N2O and CO2 emissions, suggesting that the N2O and CO2 emitted during the freeze-thaw cycles may have originated mostly from cellular materials released from lysis and death of microbial biomass rather than from soil aggregate disruption. Cumulative N2O emissions measured over the 49-day incubation period ranged from 148 mg N2O-N m-2 to 17 mg N2O-N m-2 and were highest in miscanthus followed by willow, switchgrass, and successional site. Cumulative CO2 on the other hand was highest in the successional site than any of the bioenergy crops and ranged from 25,262 mg CO2-C m-2 to 15,403 mg CO2-C m-2 after the 49 days. Higher N2O emissions in the miscanthus and willow than switchgrass and successional site were attributed to accelerated N losses as N2O. Results from our study indicate that managing perennial bioenergy crops on low productive agricultural lands to reduce freeze-thaw related GHG emissions and climate change mitigation is dependent on the crop species grown.


Assuntos
Gases de Efeito Estufa , Panicum , Gases de Efeito Estufa/análise , Dióxido de Carbono/análise , Agricultura/métodos , Solo , Óxido Nitroso/análise
19.
Molecules ; 29(8)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38675597

RESUMO

Global food production relies on annual grain crops. The reliability and productivity of these crops are threatened by adaptations to climate change and unsustainable rates of soil loss associated with their cultivation. Perennial grain crops, which do not require planting every year, have been proposed as a transformative solution to these challenges. Perennial grain crops typically rely on wild species as direct domesticates or as sources of perenniality in hybridization with annual grains. Onobrychis spp. (sainfoins) are a genus of perennial legumes domesticated as ancient forages. Baki™ bean is the tradename for pulses derived from sainfoins, with ongoing domestication underway to extend demonstrated benefits to sustainable agriculture. This study contributes to a growing body of evidence characterizing the nutritional quality of Baki™ bean. Through two studies, we investigated the safety of Baki™ bean for human consumption. We quantified heavy metals, folate, and canavanine for samples from commercial seed producers, and we quantified levels of mycotoxins, microorganisms, and pesticides in samples from a single year and seed producer, representing different varieties and production locations. The investigated analytes were not detectable or occurred at levels that do not pose a significant safety risk. Overall, this study supports the safety of Baki™ bean for human consumption as a novel pulse crop.


Assuntos
Fabaceae , Inocuidade dos Alimentos , Fabaceae/química , Fabaceae/microbiologia , Domesticação , Metais Pesados/análise , Ácido Fólico/análise , Canavanina/análise , Nutrientes/análise , Micotoxinas/análise , Praguicidas/análise
20.
Molecules ; 29(17)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39275115

RESUMO

Intermediate wheatgrass (IWG) is a promising perennial grain explored for mainstream food applications. This study investigated the effects of different germination temperatures (10, 15, and 20 °C) and durations (2, 4, and 6 days) on IWG's volatile and fatty acid (FA) profiles. A method using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) was optimized through response surface design to extract the volatile compounds, achieving ideal extraction conditions at 60 °C for 55 min. Multiple headspace extraction (MHE) was used for volatile compound quantification. Fifty-eight compounds were identified and quantified in IWG flour, mainly alcohols, aldehydes, hydrocarbons, terpenes, esters, organic acids, and ketones. The main FAs found were linoleic acid (C18:2), oleic acid (C18:1), palmitic acid (C16:0), and linolenic acid (C18:3). Principal component analysis showed a direct correlation between volatile oxidation products and FA composition. Germination at 15 °C for 6 days led to a reduced presence of aldehydes and alcohols such as nonanal and 1-pentanol. Therefore, optimized germination was successful in reducing the presence of potential off-odor compounds. This study provides valuable insights into the effects of germination on IWG flour, showing a way for its broader use in food applications.


Assuntos
Ácidos Graxos , Cromatografia Gasosa-Espectrometria de Massas , Germinação , Sementes , Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Germinação/efeitos dos fármacos , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Poaceae/química , Temperatura
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