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1.
N Engl J Med ; 390(10): 911-921, 2024 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-38393328

RESUMEN

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.).


Asunto(s)
Antiinflamatorios , Anticuerpos Monoclonales Humanizados , Síndrome de Churg-Strauss , Subunidad alfa del Receptor de Interleucina-5 , Adulto , Humanos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Enfermedad Crónica , Síndrome de Churg-Strauss/tratamiento farmacológico , Síndrome de Churg-Strauss/inmunología , Glucocorticoides/efectos adversos , Glucocorticoides/uso terapéutico , Granulomatosis con Poliangitis/tratamiento farmacológico , Granulomatosis con Poliangitis/inmunología , Recurrencia , Antiinflamatorios/administración & dosificación , Antiinflamatorios/efectos adversos , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Método Doble Ciego , Inducción de Remisión , Inyecciones Subcutáneas , Subunidad alfa del Receptor de Interleucina-5/antagonistas & inhibidores , Eosinófilos/efectos de los fármacos , Eosinófilos/inmunología
2.
Plant J ; 119(3): 1327-1335, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38804053

RESUMEN

Ear length (EL) is a key trait that greatly contributes to yield in maize. Although dozens of EL quantitative trait loci have been mapped, very few causal genes have been cloned, and the molecular mechanisms remain largely unknown. Our previous study showed that YIGE1 is involved in sugar and auxin pathways to regulate ear inflorescence meristem (IM) development and thus affects EL in maize. Here, we reveal that YIGE2, the paralog of YIGE1, regulates maize ear development and EL through auxin pathway. Knockout of YIGE2 causes a significant decrease of auxin level, IM length, floret number, EL, and grain yield. yige1 yige2 double mutants had even shorter IM and ears implying that these two genes redundantly regulate IM development and EL. The genes controlling auxin levels are differential expressed in yige1 yige2 double mutants, leading to lower auxin level. These results elucidated the critical role of YIGE2 and the redundancy between YIGE2 and YIGE1 in maize ear development, providing a new genetic resource for maize yield improvement.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Zea mays , Zea mays/genética , Zea mays/metabolismo , Zea mays/crecimiento & desarrollo , Zea mays/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Inflorescencia/genética , Inflorescencia/crecimiento & desarrollo , Meristema/genética , Meristema/crecimiento & desarrollo , Meristema/metabolismo , Sitios de Carácter Cuantitativo/genética , Mutación
3.
Plant J ; 118(2): 457-468, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38198228

RESUMEN

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.


Asunto(s)
Oxidorreductasas , Zea mays , Humanos , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Zea mays/genética , Zea mays/metabolismo , Carotenoides/metabolismo , beta Caroteno/metabolismo , Grano Comestible/genética , Grano Comestible/metabolismo , Plastidios/genética , Plastidios/metabolismo
4.
Am J Respir Crit Care Med ; 210(3): 288-297, 2024 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-38635834

RESUMEN

Background: The anti-IgE monoclonal antibody omalizumab is widely used for severe asthma. This study aimed to identify biomarkers that predict clinical improvement during 1 year of omalizumab treatment. Methods: One-year open-label Study of Mechanisms of action of Omalizumab in Severe Asthma (SoMOSA) involving 216 patients with severe (Global Initiative for Asthma step 4/5) uncontrolled atopic asthma (at least two severe exacerbations in the previous year) taking high-dose inhaled corticosteroids and long-acting ß-agonists with or without maintenance oral corticosteroids. 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 based on ⩾50% reduction in exacerbations or mOCS dose. All participants provided samples (exhaled breath, blood, sputum, urine) before and after 16 weeks of omalizumab treatment. Measurements and Main Results: A total of 191 patients completed phase 1; 63% had early improvement. Of 173 who completed phase 2, 69% had reduced exacerbations by ⩾50% and 57% (37 of 65) taking mOCSs had reduced their dose by ⩾50%. The primary outcomes 2,3-dinor-11-ß-PGF2α, GETE score, and standard clinical biomarkers (blood and sputum eosinophils, exhaled nitric oxide, serum IgE) did not predict either clinical response. Five volatile organic compounds and five plasma lipid biomarkers strongly predicted the ⩾50% reduction in exacerbations (receiver operating characteristic areas under the curve of 0.780 and 0.922, respectively) and early responses (areas under the curve of 0.835 and 0.949, respectively). In an independent cohort, gas chromatography/mass spectrometry biomarkers differentiated between severe and mild asthma. Conclusions: This is the first discovery of omics biomarkers that predict improvement in asthma with biologic agent treatment. Prospective validation and development for clinical use is justified.


Asunto(s)
Antiasmáticos , Asma , Biomarcadores , Omalizumab , Humanos , Omalizumab/uso terapéutico , Asma/tratamiento farmacológico , Asma/sangre , Masculino , Femenino , Antiasmáticos/uso terapéutico , Adulto , Persona de Mediana Edad , Biomarcadores/sangre , Resultado del Tratamiento , Índice de Severidad de la Enfermedad , Inmunoglobulina E/sangre , Esputo/citología , Anticuerpos Antiidiotipos/uso terapéutico , Pruebas Respiratorias
5.
Thorax ; 79(5): 403-411, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38124220

RESUMEN

INTRODUCTION: After puberty, females are more likely to develop asthma and in a more severe form than males. The associations between asthma and sex are complex with multiple intrinsic and external factors. AIM: To evaluate the sex differences in the characteristics and treatment of patients with severe asthma (SA) in a real-world setting. METHODS: Demographic, clinical and treatment characteristics for patients with SA in the UK Severe Asthma Registry (UKSAR) and Optimum Patient Care Research Database (OPCRD) were retrospectively analysed by sex using univariable and multivariable logistic regression analyses adjusted for year, age and hospital/practice. RESULTS: 3679 (60.9% female) patients from UKSAR and 18 369 patients (67.9% female) from OPCRD with SA were included. Females were more likely to be symptomatic with increased Asthma Control Questionnaire-6 (UKSAR adjusted OR (aOR) 1.14, 95% CI 1.09 to 1.18) and Royal College of Physicians-3 Question scores (OPCRD aOR 1.29, 95% CI 1.13 to 1.47). However, they had a higher forced expiratory volume in 1 second per cent (FEV1%) predicted (UKSAR 68.7% vs 64.8%, p<0.001) with no significant difference in peak expiratory flow. Type 2 biomarkers IgE (UKSAR 129 IU/mL vs 208 IU/mL, p<0.001) and FeNO (UKSAR 36ppb vs 46ppb, p<0.001) were lower in females with no significant difference in blood eosinophils or biological therapy. Females were less likely to be on maintenance oral corticosteroids (UKSAR aOR 0.86, 95% CI 0.75 to 0.99) but more likely to be obese (UKSAR aOR 1.67, 95% CI 145 to 1.93; OPCRD SA aOR 1.46, 95% CI 1.34 to 1.58). CONCLUSIONS: Females had increased symptoms and were more likely to be obese despite higher FEV1% predicted and lower type 2 biomarkers with consistent and clinically important differences across both datasets.


Asunto(s)
Asma , Humanos , Femenino , Masculino , Estudios Retrospectivos , Estudios Transversales , Asma/tratamiento farmacológico , Asma/epidemiología , Biomarcadores , Obesidad , Reino Unido/epidemiología
6.
Eur Respir J ; 64(1)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38575162

RESUMEN

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: Out 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 out of 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.


Asunto(s)
Antiasmáticos , Anticuerpos Monoclonales Humanizados , Asma , Humanos , Masculino , Femenino , Asma/tratamiento farmacológico , Persona de Mediana Edad , Anticuerpos Monoclonales Humanizados/uso terapéutico , Estudios Retrospectivos , Antiasmáticos/uso terapéutico , Adulto , Resultado del Tratamiento , Anciano , Eosinófilos , Corticoesteroides/uso terapéutico , Corticoesteroides/administración & dosificación , Eosinofilia/tratamiento farmacológico
7.
Clin Exp Allergy ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39084909

RESUMEN

BACKGROUND: Benralizumab has been reported to lead to clinical remission of severe eosinophilic asthma (SEA) at 1 year in some patients. However, whether this is maintained over a longer term remains unclear. Additionally, the impact of pulmonary and extrapulmonary comorbidities on the ability to meet remission is poorly understood. METHODS: Clinical outcomes including remission of SEA with benralizumab at 1 and 2 years were assessed retrospectively in a real-world UK multi-centre severe asthma cohort. The presence of clinically relevant pulmonary and extrapulmonary comorbidities associated with respiratory symptoms was recorded. Analyses to identify factors associated with the ability to meet remission were performed. RESULTS: In total, 276 patients with SEA treated with benralizumab including 113 patients who had switched from a previous biologic to benralizumab were included. Overall, clinical remission was met in 17% (n = 31/186) and 32% (n = 43/133) of patients at 1 and 2 years, respectively. This increased to 28% at 1 year and 49% at 2 years once patients with pulmonary and/or extrapulmonary comorbidities were excluded. Body mass index (BMI) and maintenance OCS (mOCS) use demonstrated a negative association with clinical remission at 1 (BMI: OR: 0.89, 95% CI: 0.82-0.96, p < 0.01; mOCS: OR: 0.94, 95% CI: 0.89-0.99, p < 0.05) and 2 years (BMI: OR: 0.93, 95% CI: 0.87-0.99, p < 0.05; mOCS: OR: 0.95, 95% CI: 0.89-0.99, p < 0.05). CONCLUSIONS: In this long-term, real-world study, patients with SEA demonstrated the ability to meet and sustain clinical remission when treated with benralizumab. The presence of comorbidities including obesity, which are known to be independently associated with respiratory symptoms, reduced the likelihood of meeting clinical remission.

8.
Allergy ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39087443

RESUMEN

The role of eosinophils in airway inflammation and asthma pathogenesis is well established, with raised eosinophil counts in blood and sputum associated with increased disease severity and risk of asthma exacerbation. Conversely, there is also preliminary evidence suggesting antiviral properties of eosinophils in the airways. These dual roles for eosinophils are particularly pertinent as respiratory virus infections contribute to asthma exacerbations. Biologic therapies targeting key molecules implicated in eosinophil-associated pathologies have been approved in patients with severe asthma and, therefore, the effects of depleting eosinophils in a clinical setting are of considerable interest. This review discusses the pathological and antiviral roles of eosinophils in asthma and exacerbations. We also highlight the significant reduction in asthma exacerbations seen with biologic therapies, even at the height of the respiratory virus season. Furthermore, we discuss the implications of these findings in relation to the role of eosinophils in inflammation and antiviral responses to respiratory virus infection in asthma.

9.
Allergy ; 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38923444

RESUMEN

BACKGROUND: Biologic asthma therapies reduce exacerbations and long-term oral corticosteroids (LTOCS) use in randomized controlled trials (RCTs); however, there are limited data on outcomes among patients ineligible for RCTs. Hence, we investigated responsiveness to biologics in a real-world population of adults with severe asthma. METHODS: Adults in the International Severe Asthma Registry (ISAR) with ≥24 weeks of follow-up were grouped into those who did, or did not, initiate biologics (anti-IgE, anti-IL5/IL5R, anti-IL4/13). Treatment responses were examined across four domains: forced expiratory volume in 1 second (FEV1) increase by ≥100 mL, improved asthma control, annualized exacerbation rate (AER) reduction ≥50%, and any LTOCS dose reduction. Super-response criteria were: FEV1 increase by ≥500 mL, new well-controlled asthma, no exacerbations, and LTOCS cessation or tapering to ≤5 mg/day. RESULTS: 5.3% of ISAR patients met basic RCT inclusion criteria; 2116/8451 started biologics. Biologic initiators had worse baseline impairment than non-initiators, despite having similar biomarker levels. Half or more of initiators had treatment responses: 59% AER reduction, 54% FEV1 increase, 49% improved control, 49% reduced LTOCS, of which 32%, 19%, 30%, and 39%, respectively, were super-responses. Responses/super-responses were more frequent in biologic initiators than in non-initiators; nevertheless, ~40-50% of initiators did not meet response criteria. CONCLUSIONS: Most patients with severe asthma are ineligible for RCTs of biologic therapies. Biologics are initiated in patients who have worse baseline impairments than non-initiators despite similar biomarker levels. Although biologic initiators exhibited clinical responses and super-responses in all outcome domains, 40-50% did not meet the response criteria.

10.
Ann Allergy Asthma Immunol ; 132(5): 610-622.e7, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38151100

RESUMEN

BACKGROUND: There is little agreement on clinically useful criteria for identifying real-world responders to biologic treatments for asthma. OBJECTIVE: To investigate the impact of pre-biologic impairment on meeting domain-specific biologic responder definitions in adults with severe asthma. METHODS: This was a longitudinal, cohort study across 22 countries participating in the International Severe Asthma Registry (https://isaregistries.org/) between May 2017 and January 2023. Change in 4 asthma domains (exacerbation rate, asthma control, long-term oral corticosteroid [LTOCS] dose, and lung function) was assessed from biologic initiation to 1 year post-treatment (minimum 24 weeks). Pre- to post-biologic changes for responders and nonresponders were described along a categorical gradient for each domain derived from pre-biologic distributions (exacerbation rate: 0 to 6+/y; asthma control: well controlled to uncontrolled; LTOCS: 0 to >30 mg/d; percent-predicted forced expiratory volume in 1 second [ppFEV1]: <50% to ≥80%). RESULTS: Percentage of biologic responders (ie, those with a category improvement pre- to post-biologic) varied by domain and increased with greater pre-biologic impairment, increasing from 70.2% to 90.0% for exacerbation rate, 46.3% to 52.3% for asthma control, 31.1% to 58.5% for LTOCS daily dose, and 35.8% to 50.6% for ppFEV1. The proportion of patients having improvement post-biologic tended to be greater for anti-IL-5/5R compared with for anti-IgE for exacerbation, asthma control, and ppFEV1 domains, irrespective of pre-biologic impairment. CONCLUSION: Our results provide realistic outcome-specific post-biologic expectations for both physicians and patients, will be foundational to inform future work on a multidimensional approach to define and assess biologic responders and response, and may enhance appropriate patient selection for biologic therapies. TRIAL REGISTRATION: The ISAR database has ethical approval from the Anonymous Data Ethics Protocols and Transparency (ADEPT) committee (ADEPT0218) and is registered with the European Union Electronic Register of Post-Authorization studies (ENCEPP/DSPP/23720). The study was designed, implemented, and reported in compliance with the European Network Centres for Pharmacoepidemiology and Pharmacovigilance (ENCEPP) Code of Conduct (EUPAS38288) and with all applicable local and international laws and regulation, and registered with ENCEPP (https://www.encepp.eu/encepp/viewResource.htm?id=38289). Governance was provided by ADEPT (registration number: ADEPT1220).


Asunto(s)
Antiasmáticos , Asma , Humanos , Asma/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Antiasmáticos/uso terapéutico , Estudios Longitudinales , Resultado del Tratamiento , Índice de Severidad de la Enfermedad , Corticoesteroides/uso terapéutico , Sistema de Registros , Anciano
11.
BMC Health Serv Res ; 24(1): 658, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783284

RESUMEN

BACKGROUND: The Hawai'i State Department of Health, Child and Adolescent Mental Health Division (CAMHD) has maintained a longstanding partnership with Substance Abuse and Mental Health Services Administration (SAMHSA) to enhance capacity and quality of community-based mental health services. The current study explored CAMHD's history of SAMHSA system of care (SOC) awards and identified common themes, lessons learned, and recommendations for future funding. METHODS: Employing a two-phase qualitative approach, the study first conducted content analysis on seven final project reports, identifying themes and lessons learned based on SOC values and principles. Subsequently, interviews were conducted with 11 system leaders in grant projects and SOC award projects within the state. All data from project reports and interview transcripts were independently coded and analyzed using rapid qualitative analysis techniques. RESULTS: Content validation and interview coding unveiled two content themes, interagency collaboration and youth and family voice, as areas that required long-term and consistent efforts across multiple projects. In addition, two general process themes, connection and continuity, emerged as essential approaches to system improvement work. The first emphasizes the importance of fostering connections in family, community, and culture, as well as within workforce members and child-serving agencies. The second highlights the importance of nurturing continuity throughout the system, from interagency collaboration to individual treatment. CONCLUSIONS: The study provides deeper understanding of system of care evaluations, offering guidance to enhance and innovate youth mental health systems. The findings suggest that aligning state policies with federal guidelines and implementing longer funding mechanisms may alleviate administrative burdens.


Asunto(s)
Investigación Cualitativa , United States Substance Abuse and Mental Health Services Administration , Humanos , Hawaii , Adolescente , Estados Unidos , Trastornos Relacionados con Sustancias/terapia , Niño , Servicios de Salud del Adolescente/organización & administración , Entrevistas como Asunto , Servicios de Salud Mental/organización & administración , Servicios Comunitarios de Salud Mental/organización & administración
13.
Curr Opin Plant Biol ; 79: 102541, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38663258

RESUMEN

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.


Asunto(s)
Plasmodesmos , ARN Mensajero , ARN Mensajero/metabolismo , ARN Mensajero/genética , Plasmodesmos/metabolismo , Ribonucleoproteínas/metabolismo , Ribonucleoproteínas/genética , ARN de Planta/metabolismo , ARN de Planta/genética , Transporte de ARN , Plantas/metabolismo , Plantas/genética , Transducción de Señal , Comunicación Celular
14.
Mol Plant ; 17(1): 50-74, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38130059

RESUMEN

Meristems are stem cell-containing structures that produce all plant organs and are therefore important targets for crop improvement. Developmental regulators control the balance and rate of cell divisions within the meristem. Altering these regulators impacts meristem architecture and, as a consequence, plant form. In this review, we discuss genes involved in regulating the shoot apical meristem, inflorescence meristem, axillary meristem, root apical meristem, and vascular cambium in plants. We highlight several examples showing how crop breeders have manipulated developmental regulators to modify meristem growth and alter crop traits such as inflorescence size and branching patterns. Plant transformation techniques are another innovation related to plant meristem research because they make crop genome engineering possible. We discuss recent advances on plant transformation made possible by studying genes controlling meristem development. Finally, we conclude with discussions about how meristem research can contribute to crop improvement in the coming decades.


Asunto(s)
Productos Agrícolas , Meristema , Productos Agrícolas/genética , Meristema/genética , Inflorescencia/genética , División Celular , Regulación de la Expresión Génica de las Plantas
15.
Mol Plant ; 17(7): 1019-1037, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38877701

RESUMEN

Maize develops separate ear and tassel inflorescences with initially similar morphology but ultimately different architecture and sexuality. The detailed regulatory mechanisms underlying these changes still remain largely unclear. In this study, through analyzing the time-course meristem transcriptomes and floret single-cell transcriptomes of ear and tassel, we revealed the regulatory dynamics and pathways underlying inflorescence development and sex differentiation. We identified 16 diverse gene clusters with differential spatiotemporal expression patterns and revealed biased regulation of redox, programmed cell death, and hormone signals during meristem differentiation between ear and tassel. Notably, based on their dynamic expression patterns, we revealed the roles of two RNA-binding proteins in regulating inflorescence meristem activity and axillary meristem formation. Moreover, using the transcriptional profiles of 53 910 single cells, we uncovered the cellular heterogeneity between ear and tassel florets. We found that multiple signals associated with either enhanced cell death or reduced growth are responsible for tassel pistil suppression, while part of the gibberellic acid signal may act non-cell-autonomously to regulate ear stamen arrest during sex differentiation. We further showed that the pistil-protection gene SILKLESS 1 (SK1) functions antagonistically to the known pistil-suppression genes through regulating common molecular pathways, and constructed a regulatory network for pistil-fate determination. Collectively, our study provides a deep understanding of the regulatory mechanisms underlying inflorescence development and sex differentiation in maize, laying the foundation for identifying new regulators and pathways for maize hybrid breeding and improvement.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Inflorescencia , Meristema , Transcriptoma , Zea mays , Zea mays/genética , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo , Meristema/crecimiento & desarrollo , Meristema/genética , Meristema/metabolismo , Inflorescencia/crecimiento & desarrollo , Inflorescencia/genética , Inflorescencia/metabolismo , Transcriptoma/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Diferenciación Sexual/genética , Análisis de la Célula Individual
16.
Mol Genet Metab Rep ; 40: 101117, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39101156

RESUMEN

Background: Biochemical testing is a common first-tier approach in the setting of genetic evaluation of patients with unexplained developmental delay. However, results can be unclear, and a plan for second-tier analysis must be determined based on the patient's biochemical results and clinical presentation - in many cases, triggering a diagnostic odyssey. Case presentation: A male patient from the United States presenting with unexplained developmental delay, microcephaly, hypotonia, and feeding difficulties was referred for clinical genetic evaluation at age 8 months. Biochemical testing revealed an isolated marked elevation of glutaric acid on urine organic acid profile, without elevations of related metabolites. Further testing included GCDH sequencing, a neurometabolic gene panel, chromosomal microarray, Prader Willi/Angelman testing, and lysosomal disease enzyme panel, all of which were non-diagnostic. The patient had persistent developmental delay and hypotonia, dystonia, sensorineural hearing loss, and abnormal brain myelination on magnetic resonance imaging. Whole exome sequencing (WES) was performed and revealed a dual diagnosis of glutaric aciduria III (GA III) and BCAP31-related disorder, an X-linked intellectual disability syndrome, caused by a novel pathogenic variant. Conclusions: GA III has historically been considered clinically benign, with few reported cases. This patient's presenting symptoms were similar to those commonly seen in GA I and GA II, however the biochemical abnormalities were not consistent with these disorders, prompting additional molecular and biochemical testing. Ultimately, WES confirmed a diagnosis of BCAP31-related syndrome, a rare neurological disorder, which explained the patient's presenting symptoms. WES also identified a secondary diagnosis of GA III. We present a patient with two rare genetic conditions, highlighting the importance of deep phenotyping and the utility of WES in the setting of a patient with dual genetic diagnoses.

17.
bioRxiv ; 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38496543

RESUMEN

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.

18.
J Allergy Clin Immunol Pract ; 12(8): 2074-2083.e4, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38677588

RESUMEN

BACKGROUND: Benralizumab and mepolizumab are interleukin (IL)-5Rα/interleukin-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 every 4 weeks (q4w) or every 8 weeks (q8w) for adults (aged 18-75 y) 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 y) 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, serious adverse events, 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 adverse event in both studies (MELTEMI q8w 46.5%; q4w 47.3%; COLUMBA, 48.7%). Asthma-related events were the most common serious adverse events 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.


Asunto(s)
Antiasmáticos , Anticuerpos Monoclonales Humanizados , Asma , Humanos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Adulto , Persona de Mediana Edad , Masculino , Femenino , Anciano , Asma/tratamiento farmacológico , Antiasmáticos/uso terapéutico , Antiasmáticos/efectos adversos , Adolescente , Adulto Joven
19.
J Allergy Clin Immunol Glob ; 3(2): 100225, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38524787

RESUMEN

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.

20.
Pragmat Obs Res ; 15: 53-64, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505738

RESUMEN

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.

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