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1.
Nat Plants ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745100

RESUMO

A comprehensive understanding of inflorescence development is crucial for crop genetic improvement, as inflorescence meristems give rise to reproductive organs and determine grain yield. However, dissecting inflorescence development at the cellular level has been challenging owing to a lack of specific marker genes to distinguish among cell types, particularly in different types of meristems that are vital for organ formation. In this study, we used spatial enhanced resolution omics-sequencing (Stereo-seq) to construct a precise spatial transcriptome map of the developing maize ear primordium, identifying 12 cell types, including 4 newly defined cell types found mainly in the inflorescence meristem. By extracting the meristem components for detailed clustering, we identified three subtypes of meristem and validated two MADS-box genes that were specifically expressed at the apex of determinate meristems and involved in stem cell determinacy. Furthermore, by integrating single-cell RNA transcriptomes, we identified a series of spatially specific networks and hub genes that may provide new insights into the formation of different tissues. In summary, this study provides a valuable resource for research on cereal inflorescence development, offering new clues for yield improvement.

2.
Front Immunol ; 15: 1361891, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711495

RESUMO

Background: To date, studies investigating the association between pre-biologic biomarker levels and post-biologic outcomes have been limited to single biomarkers and assessment of biologic efficacy from structured clinical trials. Aim: To elucidate the associations of pre-biologic individual biomarker levels or their combinations with pre-to-post biologic changes in asthma outcomes in real-life. Methods: This was a registry-based, cohort study using data from 23 countries, which shared data with the International Severe Asthma Registry (May 2017-February 2023). The investigated biomarkers (highest pre-biologic levels) were immunoglobulin E (IgE), blood eosinophil count (BEC) and fractional exhaled nitric oxide (FeNO). Pre- to approximately 12-month post-biologic change for each of three asthma outcome domains (i.e. exacerbation rate, symptom control and lung function), and the association of this change with pre-biologic biomarkers was investigated for individual and combined biomarkers. Results: Overall, 3751 patients initiated biologics and were included in the analysis. No association was found between pre-biologic BEC and pre-to-post biologic change in exacerbation rate for any biologic class. However, higher pre-biologic BEC and FeNO were both associated with greater post-biologic improvement in FEV1 for both anti-IgE and anti-IL5/5R, with a trend for anti-IL4Rα. Mean FEV1 improved by 27-178 mL post-anti-IgE as pre-biologic BEC increased (250 to 1000 cells/µL), and by 43-216 mL and 129-250 mL post-anti-IL5/5R and -anti-IL4Rα, respectively along the same BEC gradient. Corresponding improvements along a FeNO gradient (25-100 ppb) were 41-274 mL, 69-207 mL and 148-224 mL for anti-IgE, anti-IL5/5R, and anti-IL4Rα, respectively. Higher baseline BEC was also associated with lower probability of uncontrolled asthma (OR 0.392; p=0.001) post-biologic for anti-IL5/5R. Pre-biologic IgE was a poor predictor of subsequent pre-to-post-biologic change for all outcomes assessed for all biologics. The combination of BEC + FeNO marginally improved the prediction of post-biologic FEV1 increase (adjusted R2: 0.751), compared to BEC (adjusted R2: 0.747) or FeNO alone (adjusted R2: 0.743) (p=0.005 and <0.001, respectively); however, this prediction was not improved by the addition of IgE. Conclusions: The ability of higher baseline BEC, FeNO and their combination to predict biologic-associated lung function improvement may encourage earlier intervention in patients with impaired lung function or at risk of accelerated lung function decline.


Assuntos
Asma , Produtos Biológicos , Biomarcadores , Eosinófilos , Imunoglobulina E , Humanos , Asma/tratamento farmacológico , Asma/diagnóstico , Asma/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Adulto , Eosinófilos/imunologia , Produtos Biológicos/uso terapêutico , Antiasmáticos/uso terapêutico , Resultado do Tratamento , Sistema de Registros , Índice de Gravidade de Doença , Contagem de Leucócitos , Óxido Nítrico/metabolismo , Idoso , Estudos de Coortes
3.
Curr Opin Plant Biol ; 79: 102541, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38663258

RESUMO

Messenger RNAs (mRNAs) are the templates for protein translation but can also act as non-cell-autonomous signaling molecules. Plants input endogenous and exogenous cues to mobile mRNAs and output them to local or systemic target cells and organs to support specific plant responses. Mobile mRNAs form ribonucleoprotein (RNP) complexes with proteins during transport. Components of these RNP complexes could interact with plasmodesmata (PDs), a major mediator of mRNA transport, to ensure mRNA mobility and transport selectivity. Based on advances in the last two to three years, this review summarizes mRNA transport mechanisms in local and systemic signaling from the perspective of RNP complex formation and PD transport. We also discuss the physiological roles of endogenous mRNA transport and the recently revealed roles of non-cell-autonomous mRNAs in inter-organism communication.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38677588

RESUMO

BACKGROUND: Benralizumab and mepolizumab are IL-5Rα/IL-5-targeted monoclonal antibodies indicated as add-on treatments for patients with uncontrolled severe eosinophilic asthma (SEA). OBJECTIVE: To evaluate and compare the safety of benralizumab and mepolizumab among patients with SEA treated in MELTEMI and COLUMBA open-label, long-term extension studies, respectively. METHODS: MELTEMI was an extension study of benralizumab Q4W or Q8W for adults (aged 18-75 years) with SEA. MELTEMI participants transitioned from the BORA extension, preceded by participation in 1 of 3 placebo-controlled studies (SIROCCO, CALIMA, or ZONDA). COLUMBA was an extension study of mepolizumab for patients (aged ≥12 years) with SEA who transitioned from the dose-ranging DREAM study. Safety endpoints were presented as drug exposure patient years (MELTEMI, Q4W 784.28, Q8W 797.03; COLUMBA 1,201) for nonserious adverse events (AEs), serious adverse events (SAEs), and infections; malignancies were counted numerically. RESULTS: This analysis included 446 MELTEMI patients (benralizumab Q4W, 220; benralizumab Q8W, 226) and 347 COLUMBA patients (mepolizumab Q4W). Viral upper respiratory tract infection was the most common nonserious AE in both studies (MELTEMI Q8W, 46.5%; Q4W, 47.3%; COLUMBA, 48.7%). Asthma-related events were the most common SAE in both studies: MELTEMI 8.0% (Q8W) and 8.6% (Q4W) and COLUMBA 9.5%. Serious infections included pneumonia (MELTEMI Q8W, 2 [0.9%]; COLUMBA, 6 [1.7%]); cellulitis (MELTEMI Q8W, 1 [0.4%]; COLUMBA, 2 [0.6%]); and respiratory tract infections (COLUMBA, 2 [0.6%]). COLUMBA reported 6 malignancies and MELTEMI reported 4 malignancies in each group. CONCLUSIONS: This analysis demonstrated generally similar safety events between mepolizumab and benralizumab in patients with SEA.

5.
Eur Respir J ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575162

RESUMO

BACKGROUND: Pivotal Phase 3 trials and real-world studies have demonstrated benralizumab's overall efficacy and safety in severe eosinophilic asthma (SEA). Additional large-cohort data are needed to confirm its real-world effectiveness in SEA according to previous biologic use and key baseline characteristics important for treatment selection. METHODS: XALOC-1 is a large, multinational, retrospective, observational, real-world study programme of benralizumab in adults with SEA. This 48-week integrated analysis assessed annualised exacerbation rate (AER), maintenance oral corticosteroid (mOCS) use, asthma symptom control and lung function during a 12-month baseline period and up to 48 weeks after benralizumab initiation. Subgroup analyses were based on previous biologic use and key baseline clinical characteristics (mOCS use, blood eosinophil count, exacerbation history, age at asthma diagnosis, fractional exhaled nitric oxide level and presence of atopy and chronic rhinosinusitis with nasal polyps). RESULTS: Of 1002 patients analysed, 380 were biologic-experienced. At Week 48, 71.3% were exacerbation-free (versus 17.2% at baseline); relative reduction in AER was 82.7% overall and 72.9% in biologic-experienced patients; rates were maintained across all key clinical characteristic subgroups. Of patients using mOCS at baseline (n=274), 47.4% (130/274) eliminated their use by Week 48; the mean reduction from baseline in daily dose was 51.2% and, notably, 34.9% in biologic-experienced patients (n=115). Clinically significant improvements in asthma symptom control and lung function were observed. CONCLUSION: In this large, real-world programme, SEA patients treated with benralizumab had substantial improvements in clinical outcomes irrespective of previous biologic use and key clinical characteristics important to therapeutic decision-making in clinical practice.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38583517

RESUMO

BACKGROUND: Dupilumab is an anti-IL4R monoclonal antibody (mAb) with proven efficacy in severe eosinophilic asthma (SEA). A suboptimal response to anti-IL5/5R mAbs is seen in some patients with ongoing evidence of T2 inflammation. OBJECTIVE: To understand whether targeting IL-13 pathways with dupilumab in these patients may lead to better clinical outcomes. METHODS: We performed a retrospective analysis of the extended clinical effectiveness of dupilumab up to 2 years of treatment in patients with SEA who had not responded adequately to anti-IL5/5R biologics. Ability to achieve clinical remission and change in the remission domains of exacerbation rate (AER), maintenance oral corticosteroid dose (mOCS), lung function (FEV1) and asthma control (ACQ6) were recorded. RESULTS: Thirty-seven patients (mean age 41, 70% female) were included in the analysis. The mean (SD) AER fell by almost 90% from 3.16(1.28) at dupilumab initiation to 0.35(0.72) after 1 year. The median (IQR) mOCS dose (n=20) fell from 10(5-25) mg to 0 (0-5) mg at 1 year, with 14/20 (70%) able to stop prednisolone altogether. Clinical remission was achieved in 16/37 (43%). Patients who achieved remission had a higher pre-IL5/5R FeNO level (85ppb [39-198] vs 75ppb [42-96], p=0.03). CONCLUSION: Significant improvements in clinical outcomes are possible following a switch to dupilumab in patients experiencing a suboptimal response to anti-IL5/5R therapies. A higher FeNO in poor responders to anti-IL5/5R who achieve remission with dupilumab is suggestive of an IL-13 driven sub-phenotype of T2-high asthma in which the eosinophil appears unlikely to play a key role in the disease pathogenesis.

7.
HGG Adv ; 5(3): 100288, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38566418

RESUMO

Biallelic loss-of-function variants in the MUSK gene result in two allelic disorders: (1) congenital myasthenic syndrome (CMS; OMIM: 616325), a neuromuscular disorder that has a range of severity from severe neonatal-onset weakness to mild adult-onset weakness, and (2) fetal akinesia deformation sequence (OMIM: 208150), a form of pregnancy loss characterized by severe muscle weakness in the fetus. The MUSK gene codes for muscle-specific kinase (MuSK), a receptor tyrosine kinase involved in the development of the neuromuscular junction. Here, we report a case of neonatal-onset MUSK-related CMS in a patient harboring compound heterozygous deletions in the MUSK gene, including (1) a deletion of exons 2-3 leading to an in-frame MuSK protein lacking the immunoglobulin 1 (Ig1) domain and (2) a deletion of exons 7-11 leading to an out-of-frame, truncated MuSK protein. Individual domains of the MuSK protein have been elucidated structurally; however, a complete MuSK structure generated by machine learning algorithms has clear inaccuracies. We modify a predicted AlphaFold structure and integrate previously reported domain-specific structural data to suggest a MuSK protein that dimerizes in two locations (Ig1 and the transmembrane domain). We analyze known pathogenic variants in MUSK to discover domain-specific genotype-phenotype correlations; variants that lead to a loss of protein expression, disruption of the Ig1 domain, or Dok-7 binding are associated with the most severe phenotypes. A conceptual model is provided to explain the severe phenotypes seen in Ig1 variants and the poor response of our patient to pyridostigmine.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38635834

RESUMO

BACKGROUND: The anti-IgE monoclonal, omalizumab, is widely used for severe asthma. This study aimed to identify biomarkers that predict clinical improvement during one year of omalizumab treatment. METHODS: 1-year, open-label, Study of Mechanisms of action of Omalizumab in Severe Asthma (SoMOSA) involving 216 severe (GINA step 4/5) uncontrolled atopic asthmatics (≥2 severe exacerbations in previous year) on high-dose inhaled corticosteroids, long-acting ß-agonists, ± mOCS. It had two phases: 0-16 weeks, to assess early clinical improvement by Global Evaluation of Therapeutic Effectiveness (GETE), and 16-52 weeks, to assess late responses by ≥50% reduction in exacerbations or dose of maintenance oral corticosteroids (mOCS). All participants provided samples (exhaled breath, blood, sputum, urine) before and after 16 weeks of omalizumab treatment. RESULTS: 191 patients completed phase 1; 63% had early improvement. Of 173 who completed phase 2, 69% had reduced exacerbations by ≥50%, while 57% (37/65) on mOCS reduced their dose by ≥50%. The primary outcome 2, 3-dinor-11-ß-PGF2α, GETE and standard clinical biomarkers (blood and sputum eosinophils, exhaled nitric oxide, serum IgE) did not predict either clinical response. Five breathomics (GC-MS) and 5 plasma lipid biomarkers strongly predicted the ≥50% reduction in exacerbations (receiver operating characteristic area under the curve (AUC): 0.780 and 0.922, respectively) and early responses (AUC:0.835 and 0.949, respectively). In independent cohorts, the GC-MS biomarkers differentiated between severe and mild asthma. Conclusions This is the first discovery of omics biomarkers that predict improvement to a biologic for asthma. Their prospective validation and development for clinical use is justified. This article is open access and distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).

9.
J Allergy Clin Immunol Glob ; 3(2): 100225, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38524787

RESUMO

Background: Increasing frequency of intermittent oral corticosteroid (OCS) prescription and cumulative OCS exposure increase the risk of OCS-related adverse outcomes. Objective: We sought to describe the evolution and trajectory of intermittent OCS prescription patterns in patients with asthma and investigate risk factors independently associated with transitioning to a frequent prescription pattern. Methods: This historical cohort study included patients with active asthma managed in UK primary care and included in the Optimum Patient Care Research Database (OPCRD; opcrd.co.uk). Intermittent OCS prescription patterns were categorized as sporadic, infrequent, moderately frequent, or frequent. Prescription pattern sequences were described for those who had a frequent sequence in their final year of prescribing. We examined associations between OCS prescription pattern and the hazard of transitioning into a frequent intermittent OCS prescription pattern using multivariable Cox regression with a 10-year look-back period. Results: Of 105,229 patients with intermittent OCS prescriptions, 57.1% (n = 60,083) had a frequent OCS prescription pattern at some point. Irrespective of baseline pattern, most patients transitioned to frequent prescription during the look back. The strongest risk factors were a more frequent prescription pattern at the start of look-back period, a lower percentage peak expiratory flow rate, and higher Global Initiative for Asthma treatment step. Older age, female sex, obesity, and active smoking were also associated with a higher risk of transitioning. Conclusion: Our findings help identify those most at risk of transitioning to frequent intermittent OCS receipt and encourage earlier intervention with OCS-sparing treatments.

10.
bioRxiv ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38496543

RESUMO

Stem cells in plant shoots are a rare population of cells that produce leaves, fruits and seeds, vital sources for food and bioethanol. Uncovering regulators expressed in these stem cells will inform crop engineering to boost productivity. Single-cell analysis is a powerful tool for identifying regulators expressed in specific groups of cells. However, accessing plant shoot stem cells is challenging. Recent single-cell analyses of plant shoots have not captured these cells, and failed to detect stem cell regulators like CLAVATA3 and WUSCHEL . In this study, we finely dissected stem cell-enriched shoot tissues from both maize and arabidopsis for single-cell RNA-seq profiling. We optimized protocols to efficiently recover thousands of CLAVATA3 and WUSCHEL expressed cells. A cross-species comparison identified conserved stem cell regulators between maize and arabidopsis. We also performed single-cell RNA-seq on maize stem cell overproliferation mutants to find additional candidate regulators. Expression of candidate stem cell genes was validated using spatial transcriptomics, and we functionally confirmed roles in shoot development. These candidates include a family of ribosome-associated RNA-binding proteins, and two families of sugar kinase genes related to hypoxia signaling and cytokinin hormone homeostasis. These large-scale single-cell profiling of stem cells provide a resource for mining stem cell regulators, which show significant association with yield traits. Overall, our discoveries advance the understanding of shoot development and open avenues for manipulating diverse crops to enhance food and energy security.

11.
Pragmat Obs Res ; 15: 53-64, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505738

RESUMO

Purpose: Associations between systemic glucocorticoid (SGC) exposure and risk for adverse outcomes have spurred a move toward steroid-sparing treatment strategies. Real-world changes in SGC exposure over time, after the introduction of steroid-sparing treatment strategies, reveal areas of successful risk mitigation as well as unmet needs. Patients and Methods: A population-based ecological study was performed from the Optimum Patient Care Research Database to describe SGC prescribing trends of steroid-sparing treatment strategies in primary care practices before and after licensure of biologics in the United Kingdom from 1990 to 2019. Each analysis year included patients aged ≥5 years who were registered for ≥1 year with a participating primary care practice. The primary analysis was SGC exposure, defined as total cumulative SGC dose per patient per year, for asthma, severe asthma, chronic obstructive pulmonary disease (COPD), nasal polyps, Crohn's disease, rheumatoid arthritis, ulcerative colitis, and systemic lupus erythematosus. Secondary outcomes were percentages of patients prescribed SGCs and number of SGC prescriptions per patient per year. Results: The number of patients who met study inclusion criteria ranged from 219,862 (1990) to 1,261,550 (2019). At the population level, patients with asthma or COPD accounted for 67.7% to 73.2% of patients per year with an SGC prescription. Over three decades, decreases in SGC total yearly dose ≥1000 mg have been achieved in multiple conditions. Patients with COPD prescribed SGCs increased from 5.8% (1990) to 34.8% (2017). SGC prescribing trends for severe asthma, Crohn's disease, and ulcerative colitis show decreased prescribing trends after the introduction of biologics. Conclusion: Decreases in total yearly SGC doses have been shown in multiple conditions; however, for conditions such as severe asthma and COPD, an unmet need remains for increased awareness of SGC burden and the adoption or development of SGC-sparing alternatives to reduce overuse.

12.
Chest ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38395297

RESUMO

BACKGROUND: Exacerbation frequency strongly influences treatment choices in patients with severe asthma. RESEARCH QUESTION: What is the extent of the variability of exacerbations rate across countries and its implications in disease management? STUDY DESIGN AND METHODS: We retrieved data from the International Severe Asthma Registry, an international observational cohort of patients with a clinical diagnosis of severe asthma. We identified patients ≥ 18 years of age who did not initiate any biologics prior to baseline visit. A severe exacerbation was defined as the use of oral corticosteroids for ≥ 3 days or asthma-related hospitalization/ED visit. A series of negative binomial models were applied to estimate country-specific severe exacerbation rates during 365 days of follow-up, starting from a naïve model with country as the only variable to an adjusted model with country as a random-effect term and patient and disease characteristics as independent variables. RESULTS: The final sample included 7,510 patients from 17 countries (56% from the United States), contributing to 1,939 severe exacerbations (0.27/person-year). There was large between-country variation in observed severe exacerbation rate (minimum, 0.04 [Argentina]; maximum, 0.88 [Saudi Arabia]; interquartile range, 0.13-0.54), which remained substantial after adjusting for patient characteristics and sampling variability (interquartile range, 0.16-0.39). INTERPRETATION: Individuals with similar patient characteristics but coming from different jurisdictions have varied severe exacerbation risks, even after controlling for patient and disease characteristics. This suggests unknown patient factors or system-level variations at play. Disease management guidelines should recognize such between-country variability. Risk prediction models that are calibrated for each jurisdiction will be needed to optimize treatment strategies.

13.
N Engl J Med ; 390(10): 911-921, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38393328

RESUMO

BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a vasculitis characterized by eosinophilic inflammation. Benralizumab, a monoclonal antibody against the interleukin-5α receptor expressed on eosinophils, may be an option for treating EGPA. METHODS: We conducted a multicenter, double-blind, phase 3, randomized, active-controlled noninferiority trial to evaluate the efficacy and safety of benralizumab as compared with mepolizumab. Adults with relapsing or refractory EGPA who were receiving standard care were randomly assigned in a 1:1 ratio to receive benralizumab (30 mg) or mepolizumab (300 mg) subcutaneously every 4 weeks for 52 weeks. The primary end point was remission at weeks 36 and 48 (prespecified noninferiority margin, -25 percentage points). Secondary end points included the accrued duration of remission, time to first relapse, oral glucocorticoid use, eosinophil count, and safety. RESULTS: A total of 140 patients underwent randomization (70 assigned to each group). The adjusted percentage of patients with remission at weeks 36 and 48 was 59% in the benralizumab group and 56% in the mepolizumab group (difference, 3 percentage points; 95% confidence interval [CI], -13 to 18; P = 0.73 for superiority), showing noninferiority but not superiority of benralizumab to mepolizumab. The accrued duration of remission and the time to first relapse were similar in the two groups. Complete withdrawal of oral glucocorticoids during weeks 48 through 52 was achieved in 41% of the patients who received benralizumab and 26% of those who received mepolizumab. The mean (±SD) blood eosinophil count at baseline was 306.0±225.0 per microliter in the benralizumab group and 384.9±563.6 per microliter in the mepolizumab group, decreasing to 32.4±40.8 and 71.8±54.4 per microliter, respectively, at week 52. Adverse events were reported in 90% of the patients in the benralizumab group and 96% of those in the mepolizumab group; serious adverse events were reported in 6% and 13%, respectively. CONCLUSIONS: Benralizumab was noninferior to mepolizumab for the induction of remission in patients with relapsing or refractory EGPA. (Funded by AstraZeneca; MANDARA ClinicalTrials.gov number, NCT04157348.).


Assuntos
Anti-Inflamatórios , Anticorpos Monoclonais Humanizados , Síndrome de Churg-Strauss , Subunidade alfa de Receptor de Interleucina-5 , Adulto , Humanos , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Doença Crônica , Síndrome de Churg-Strauss/tratamento farmacológico , Síndrome de Churg-Strauss/imunologia , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Granulomatose com Poliangiite/tratamento farmacológico , Granulomatose com Poliangiite/imunologia , Recidiva , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Método Duplo-Cego , Indução de Remissão , Injeções Subcutâneas , Subunidade alfa de Receptor de Interleucina-5/antagonistas & inibidores , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia
15.
Plant J ; 118(2): 457-468, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38198228

RESUMO

Carotenoids perform a broad range of important functions in humans; therefore, carotenoid biofortification of maize (Zea mays L.), one of the most highly produced cereal crops worldwide, would have a global impact on human health. PLASTID TERMINAL OXIDASE (PTOX) genes play an important role in carotenoid metabolism; however, the possible function of PTOX in carotenoid biosynthesis in maize has not yet been explored. In this study, we characterized the maize PTOX locus by forward- and reverse-genetic analyses. While most higher plant species possess a single copy of the PTOX gene, maize carries two tandemly duplicated copies. Characterization of mutants revealed that disruption of either copy resulted in a carotenoid-deficient phenotype. We identified mutations in the PTOX genes as being causal of the classic maize mutant, albescent1. Remarkably, overexpression of ZmPTOX1 significantly improved the content of carotenoids, especially ß-carotene (provitamin A), which was increased by ~threefold, in maize kernels. Overall, our study shows that maize PTOX locus plays an important role in carotenoid biosynthesis in maize kernels and suggests that fine-tuning the expression of this gene could improve the nutritional value of cereal grains.


Assuntos
Oxirredutases , Zea mays , Humanos , Oxirredutases/genética , Oxirredutases/metabolismo , Zea mays/genética , Zea mays/metabolismo , Carotenoides/metabolismo , beta Caroteno/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , Plastídeos/genética , Plastídeos/metabolismo
16.
J Allergy Clin Immunol Pract ; 12(3): 724-732, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211889

RESUMO

BACKGROUND: Eosinophilic granulomatosis with polyangiitis (EGPA) is a multisystemic disease characterized by eosinophilic tissue inflammation. Benralizumab, an anti-IL-5 receptor (anti-IL-5R) monoclonal antibody, induces rapid depletion of eosinophils; its longer-term effect in EGPA is unknown. OBJECTIVE: To assess the real-world effectiveness and clinical remission rates of anti-IL-5R therapy in EGPA. METHODS: We performed a retrospective cohort analysis of patients with EGPA, who commenced treatment with benralizumab. Clinical remission, assessed at 1 year and 2 years after the initiation of benralizumab, was defined as an absence of active vasculitis (Birmingham Vasculitis Activity Score of 0) and an oral corticosteroid (OCS) dose of ≤4 mg/d of prednisolone. "Super-responders" were defined as patients in remission and free of any significant relapses (asthma or extrapulmonary) over the preceding 12 months. The corticosteroid-sparing capacity of benralizumab, patient-reported outcome measures, and characteristics associated with clinical remission and super-responder status were also analyzed. RESULTS: A total of 70 patients completed at least 1 year of treatment with benralizumab, of whom 53 completed 2 years. Of 70 patients, 47 (67.1%) met the definition for clinical remission at 1 year, with a similar proportion in remission at 2 years. Excluding asthma-related relapses, 61 of 70 (87.1%) patients were relapse free at 1 year, and of the 53 who completed 2 years, 45 (84.9%) were relapse free. A total of 67.9% of patients no longer needed any OCS for disease control. No significant difference was seen between antineutrophilic cytoplasmic antibody (ANCA)-positive and ANCA-negative subgroups. CONCLUSIONS: In this real-world setting of patients with EGPA, treatment with benralizumab was well tolerated and resulted in corticosteroid-free clinical remission for the majority of patients.


Assuntos
Anticorpos Monoclonais Humanizados , Asma , Síndrome de Churg-Strauss , Eosinofilia , Granulomatose com Poliangiite , Humanos , Síndrome de Churg-Strauss/tratamento farmacológico , Granulomatose com Poliangiite/tratamento farmacológico , Anticorpos Anticitoplasma de Neutrófilos , Estudos Retrospectivos , Asma/tratamento farmacológico , Corticosteroides/uso terapêutico , Recidiva
17.
Lancet ; 403(10423): 271-281, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38071986

RESUMO

BACKGROUND: Stepwise intensification of inhaled corticosteroids (ICS) is routine for severe eosinophilic asthma, despite some poor responses to high-dose ICS. Dose reductions are recommended in patients responding to biologics, but little supporting safety evidence exists. METHODS: SHAMAL was a phase 4, randomised, open-label, active-controlled study done at 22 study sites in four countries. Eligible participants were adults (aged ≥18 years) with severe eosinophilic asthma and a five-item Asthma Control Questionnaire score below 1·5 and who received at least three consecutive doses of benralizumab before screening. We randomly assigned patients (3:1) to taper their high-dose ICS to a medium-dose, low-dose, and as-needed dose (reduction group) or continue (reference group) their ICS-formoterol therapy for 32 weeks, followed by a 16-week maintenance period. The primary endpoint was the proportion of patients reducing their ICS-formoterol dose by week 32. The primary outcome was assessed in the reduction group, and safety analyses included all randomly assigned patients receiving study treatment. This study is registered at ClinicalTrials.gov, NCT04159519. FINDINGS: Between Nov 12, 2019, and Feb 16, 2023, we screened and enrolled in the run-in period 208 patients. We randomly assigned 168 (81%) to the reduction (n=125 [74%]) and reference arms (n=43 [26%]). Overall, 110 (92%) patients reduced their ICS-formoterol dose: 18 (15%) to medium-dose, 20 (17%) to low-dose, and 72 (61%) to as-needed only. In 113 (96%) patients, reductions were maintained to week 48; 114 (91%) of patients in the reduction group had zero exacerbations during tapering. Rates of adverse events were similar between groups. 91 (73%) patients had adverse events in the reduction group and 35 (83%) in the reference group. 17 patients had serious adverse events in the study: 12 (10%) in the reduction group and five (12%) in the reference group. No deaths occurred during the study. INTERPRETATION: These findings show that patients controlled on benralizumab can have meaningful reductions in ICS therapy while maintaining asthma control. FUNDING: AstraZeneca.


Assuntos
Antiasmáticos , Anticorpos Monoclonais Humanizados , Asma , Eosinofilia Pulmonar , Adulto , Humanos , Corticosteroides/uso terapêutico , Asma/tratamento farmacológico , Fumarato de Formoterol/uso terapêutico , Eosinofilia Pulmonar/induzido quimicamente
19.
Trends Cell Biol ; 34(1): 48-57, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37380581

RESUMO

Messenger RNAs (mRNAs) in multicellular organisms can act as signals transported cell-to-cell and over long distances. In plants, mRNAs traffic cell-to-cell via plasmodesmata (PDs) and over long distances via the phloem vascular system to control diverse biological processes - such as cell fate and tissue patterning - in destination organs. Research on long-distance transport of mRNAs in plants has made remarkable progress, including the cataloguing of many mobile mRNAs, characterization of mRNA features important for transport, identification of mRNA-binding proteins involved in their transport, and understanding of the physiological roles of mRNA transport. However, information on short-range mRNA cell-to-cell transport is still limited. This review discusses the regulatory mechanisms and physiological functions of mRNA transport at the cellular and whole plant levels.


Assuntos
Plantas , Transporte de RNA , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Plantas/genética , Plantas/metabolismo , Comunicação Celular , Floema/genética , Floema/metabolismo
20.
Sex Transm Dis ; 51(1): 54-60, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37889944

RESUMO

BACKGROUND: Over 30,000 mpox cases were reported during the 2022 mpox outbreak with many cases occurring among gay, bisexual and other men who have sex with men (MSM). Decreases in U.S. mpox cases were likely accelerated by a combination of vaccination and modifications to sexual behaviors associated with mpox virus transmission. We assessed reports of sexual behavior change among participants receiving mpox vaccination in Washington, DC. METHODS: During August to October 2022, 711 adults aged ≥18 years receiving mpox vaccination at two public health clinics in Washington, DC completed a self-administered questionnaire that asked whether sexual behaviors changed since learning about mpox. We calculated the frequency and percentages of participants reporting an increase, decrease, or no change in 4 of these behaviors by demographic, clinical, and behavioral characteristics with 95% confidence intervals. RESULTS: Overall, between 46% and 61% of participants reported a decrease in sexual behaviors associated with mpox virus transmission, 39% to 54% reported no change in these behaviors, and <1% reported an increase. Approximately 61% reported decreases in one-time sexual encounters (95% confidence interval [CI], 56.8%-64.7%), 54.3% reduced numbers of sex partners (95% CI, 50.4%-58.0%), 53.4% decreased sex via a dating app or sex venue (95% CI, 49.7%-58.0%), and 45.6% reported less group sex (95% CI, 40.4%-50.9%). Reported decreases in these behaviors were higher for MSM than women; in non-Hispanic Black than non-Hispanic White participants; and in participants with human immunodeficiency virus than participants without human immunodeficiency virus. CONCLUSIONS: Most participants receiving mpox vaccination reported decreasing sexual behaviors associated with mpox virus transmission, including groups disproportionately affected by the outbreak.


Assuntos
Mpox , Minorias Sexuais e de Gênero , Vacina Antivariólica , Adulto , Masculino , Feminino , Humanos , Adolescente , Homossexualidade Masculina , Monkeypox virus , District of Columbia/epidemiologia , Comportamento Sexual
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