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1.
Plant J ; 99(4): 673-685, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31009129

RESUMO

Nuclear male-sterile mutants with non-conditional, recessive and strictly monogenic inheritance are useful for both hybrid and conventional breeding systems, and have long been a research focus for many crops. In allohexaploid wheat, however, genic redundancy results in rarity of such mutants, with the ethyl methanesulfonate-induced mutant ms5 among the few reported to date. Here, we identify TaMs5 as a glycosylphosphatidylinositol-anchored lipid transfer protein required for normal pollen exine development, and by transgenic complementation demonstrate that TaMs5-A restores fertility to ms5. We show ms5 locates to a centromere-proximal interval and has a sterility inheritance pattern modulated by TaMs5-D but not TaMs5-B. We describe two allelic forms of TaMs5-D, one of which is non-functional and confers mono-factorial inheritance of sterility. The second form is functional but shows incomplete dominance. Consistent with reduced functionality, transcript abundance in developing anthers was found to be lower for TaMs5-D than TaMs5-A. At the 3B homoeolocus, we found only non-functional alleles among 178 diverse hexaploid and tetraploid wheats that include landraces and Triticum dicoccoides. Apparent ubiquity of non-functional TaMs5-B alleles suggests loss-of-function arose early in wheat evolution and, therefore, at most knockout of two homoeoloci is required for sterility. This work provides genetic information, resources and tools required for successful implementation of ms5 sterility in breeding systems for bread and durum wheats.


Assuntos
Proteínas de Plantas/metabolismo , Triticum/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Infertilidade das Plantas/genética , Infertilidade das Plantas/fisiologia , Proteínas de Plantas/genética , Pólen/metabolismo , Pólen/fisiologia , Triticum/genética , Triticum/fisiologia
2.
Plant Physiol ; 181(3): 1127-1147, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31492738

RESUMO

Stalk lodging in maize (Zea mays) causes significant yield losses due to breaking of stalk tissue below the ear node before harvest. Here, we identified the maize brittle stalk4 (bk4) mutant in a Mutator F2 population. This mutant was characterized by highly brittle aerial parts that broke easily from mechanical disturbance or in high-wind conditions. The bk4 plants displayed a reduction in average stalk diameter and mechanical strength, dwarf stature, senescence at leaf tips, and semisterility of pollen. Histological studies demonstrated a reduction in lignin staining of cells in the bk4 mutant leaves and stalk, and deformation of vascular bundles in the stalk resulting in the loss of xylem and phloem tissues. Biochemical characterization showed a significant reduction in p-coumaric acid, Glc, Man, and cellulose contents. The candidate gene responsible for bk4 phenotype is Chitinase-like1 protein (Ctl1), which is expressed at its highest levels in elongated internodes. Expression levels of secondary cell wall cellulose synthase genes (CesA) in the bk4 single mutant, and phenotypic observations in double mutants combining bk4 with bk2 or null alleles for two CesA genes, confirmed interaction of ZmCtl1 with CesA genes. Overexpression of ZmCtl1 enhanced mechanical stalk strength without affecting plant stature, senescence, or fertility. Biochemical characterization of ZmCtl1 overexpressing lines supported a role for ZmCtl1 in tensile strength enhancement. Conserved identity of CTL1 peptides across plant species and analysis of Arabidopsis (Arabidopsis thaliana) ctl1-1 ctl2-1 double mutants indicated that Ctl1 might have a conserved role in plants.


Assuntos
Quitinases/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/metabolismo , Zea mays/enzimologia , Zea mays/metabolismo , Parede Celular/genética , Parede Celular/metabolismo , Quitinases/genética , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/fisiologia , Resistência à Tração/fisiologia , Zea mays/fisiologia
3.
J Natl Compr Canc Netw ; 17(12): 1497-1504, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31805534

RESUMO

BACKGROUND: The addition of androgen deprivation therapy to radiation therapy (RT) improves survival in patients with intermediate- and high-risk prostate cancer (PCa), but it is not known whether combined androgen blockade (CAB) with a gonadotropin-releasing hormone agonist (GnRH-A) and a nonsteroidal antiandrogen improves survival over GnRH-A monotherapy. METHODS: This study evaluated patients with intermediate- and high-risk PCa diagnosed in 2001 through 2015 who underwent RT with either GnRH-A alone or CAB using the Veterans Affairs Informatics and Computing Infrastructure. Associations between CAB and prostate cancer-specific mortality (PCSM) and overall survival (OS) were determined using multivariable regression with Fine-Gray and multivariable Cox proportional hazards models, respectively. For a positive control, the effect of long-term versus short-term GnRH-A therapy was tested. RESULTS: The cohort included 8,423 men (GnRH-A, 4,529; CAB, 3,894) with a median follow-up of 5.9 years. There were 1,861 deaths, including 349 resulting from PCa. The unadjusted cumulative incidences of PCSM at 10 years were 5.9% and 6.9% for those receiving GnRH-A and CAB, respectively (P=.16). Compared with GnRH-A alone, CAB was not associated with a significant difference in covariate-adjusted PCSM (subdistribution hazard ratio [SHR], 1.05; 95% CI, 0.85-1.30) or OS (hazard ratio, 1.02; 95% CI, 0.93-1.12). For high-risk patients, long-term versus short-term GnRH-A therapy was associated with improved PCSM (SHR, 0.74; 95% CI, 0.57-0.95) and OS (SHR, 0.82; 95% CI, 0.73-0.93). CONCLUSIONS: In men receiving definitive RT for intermediate- or high-risk PCa, CAB was not associated with improved PCSM or OS compared with GnRH alone.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Hormônio Liberador de Gonadotropina/uso terapêutico , Neoplasias da Próstata/mortalidade , Idoso , Quimioterapia Combinada , Seguimentos , Humanos , Masculino , Prognóstico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Estudos Retrospectivos , Taxa de Sobrevida
4.
Plant Biotechnol J ; 16(11): 1836-1847, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29570925

RESUMO

Epigenetic variation has been associated with a wide range of adaptive phenotypes in plants, but there exist few direct means for exploiting this variation. RNAi suppression of the plant-specific gene, MutS HOMOLOG1 (MSH1), in multiple plant species produces a range of developmental changes accompanied by modulation of defence, phytohormone and abiotic stress response pathways along with methylome repatterning. This msh1-conditioned developmental reprogramming is retained independent of transgene segregation, giving rise to transgene-null 'memory' effects. An isogenic memory line crossed to wild type produces progeny families displaying increased variation in adaptive traits that respond to selection. This study investigates amenability of the MSH1 system for inducing agronomically valuable epigenetic variation in soybean. We developed MSH1 epi-populations by crossing with msh1-acquired soybean memory lines. Derived soybean epi-lines showed increase in variance for multiple yield-related traits including pods per plant, seed weight and maturity time in both glasshouse and field trials. Selected epi-F2:4 and epi-F2:5 lines showed an increase in seed yield over wild type. By epi-F2:6, we observed a return of MSH1-derived enhanced growth back to wild-type levels. Epi-populations also showed evidence of reduced epitype-by-environment (e × E) interaction, indicating higher yield stability. Transcript profiling of epi-lines identified putative signatures of enhanced growth behaviour across generations. Genes related to cell cycle, abscisic acid biosynthesis and auxin response, particularly SMALL AUXIN UP RNAs (SAURs), were differentially expressed in epi-F2:4 lines that showed increased yield when compared to epi-F2:6 . These data support the potential of MSH1-derived epigenetic variation in plant breeding for enhanced yield and yield stability.


Assuntos
Epigênese Genética , Glycine max/genética , Melhoramento Vegetal/métodos , Produção Agrícola , Epigênese Genética/genética , Perfilação da Expressão Gênica , Genes de Plantas/genética , Genes de Plantas/fisiologia , Estudos de Associação Genética , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Glycine max/crescimento & desenvolvimento
5.
Plant Physiol ; 168(1): 222-32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25736208

RESUMO

Evidence is compelling in support of a naturally occurring epigenetic influence on phenotype expression in land plants, although discerning the epigenetic contribution is difficult. Agriculturally important attributes like heterosis, inbreeding depression, phenotypic plasticity, and environmental stress response are thought to have significant epigenetic components, but unequivocal demonstration of this is often infeasible. Here, we investigate gene silencing of a single nuclear gene, MutS HOMOLOG1 (MSH1), in the tomato (Solanum lycopersicum) 'Rutgers' to effect developmental reprogramming of the plant. The condition is heritable in subsequent generations independent of the MSH1-RNA interference transgene. Crossing these transgene-null, developmentally altered plants to the isogenic cv Rutgers wild type results in progeny lines that show enhanced, heritable growth vigor under both greenhouse and field conditions. This boosted vigor appears to be graft transmissible and is partially reversed by treatment with the methylation inhibitor 5-azacytidine, implying the influence of mobile, epigenetic factors and DNA methylation changes. These data provide compelling evidence for the feasibility of epigenetic breeding in a crop plant.


Assuntos
Cruzamento , Epigênese Genética , Proteínas de Plantas/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/genética , Adaptação Fisiológica/genética , Arabidopsis/genética , Cruzamentos Genéticos , Metilação de DNA/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Padrões de Herança/genética , Fenótipo , Plantas Geneticamente Modificadas , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Reprodução , Plântula/crescimento & desenvolvimento , Análise de Sequência de RNA , Supressão Genética , Transgenes
6.
J Natl Compr Canc Netw ; 12(11): 1513-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25361797

RESUMO

Stereotactic body radiotherapy (SBRT) has become the standard of care for patients with medically inoperable early-stage non-small cell lung cancer (NSCLC). A paucity of published data exists regarding the safety of SBRT use in patients with prior pneumonectomy. This report describes 2 patients with NSCLC and prior pneumonectomy who were treated with lung SBRT and experienced a favorable treatment response with no major adverse treatment effects. The data presented herein are promising and provide early evidence that lung SBRT is a safe and feasible option in this subset of patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Idoso , Humanos , Pulmão/efeitos da radiação , Pulmão/cirurgia , Masculino , Pneumonectomia/métodos , Radiocirurgia/métodos
7.
Cureus ; 16(7): e64936, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39165474

RESUMO

While lifestyle choices or behavioral patterns remain the most significant factors influencing cancer risk, environmental exposure to certain chemicals, both manufactured and natural, may also contribute to an individual's likelihood of developing cancer. This interplay of factors, coupled with an aging demographic and shifting lifestyle patterns, has led to an increasing prevalence of cancer in recent years. This study examines the environmental and behavioral factors that contribute to anomalies in the immune system and increase the risk of developing cancer. Significant environmental and occupational factors include the contamination of air and water, exposure to radiation, contact with harmful microorganisms and pathogens, and workplace exposure to carcinogens such as asbestos, certain chemicals, and industrial pollutants. Behavioral factors, such as food, physical activity, stress, substance misuse, and sleep patterns, have a substantial impact on immunological function and the likelihood of developing cancer. For example, pollutants like benzene and arsenic can disrupt immune function and raise the risk of developing cancer. Similarly, lifestyle variables such as inactivity and poor nutrition have been linked to an increased risk of cancer. Long-term stress and substance abuse can also decrease immunological responses, increasing the risk of developing cancer. The review underlines the complexities of examining gene-environment interactions, as well as the importance of using several perspectives to fully comprehend these pathways. Future investigations should emphasize improved methodology and larger sample sizes. Public health campaigns should aim to reduce human exposure to cancer-causing compounds known as carcinogens while also encouraging the adoption of healthy behaviors and habits. Tailored preventive approaches that account for individual genetic vulnerabilities have the potential to improve cancer prevention and treatment.

8.
Cureus ; 16(7): e64738, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39156410

RESUMO

Obesity significantly impacts gut microbial composition, exacerbating metabolic dysfunction and weight gain. Traditional treatment methods often fall short, underscoring the need for innovative approaches. Glucagon-like peptide-1 (GLP-1) agonists have emerged as promising agents in obesity management, demonstrating significant potential in modulating gut microbiota. These agents promote beneficial bacterial populations, such as Bacteroides, Lactobacillus, and Bifidobacterium, while reducing harmful species like Enterobacteriaceae. By influencing gut microbiota composition, GLP-1 agonists enhance gut barrier integrity, reducing permeability and systemic inflammation, which are hallmarks of metabolic dysfunction in obesity. Additionally, GLP-1 agonists improve metabolic functions by increasing the production of short-chain fatty acids like butyrate, propionate, and acetate, which serve as energy sources for colonocytes, modulate immune responses, and enhance the production of gut hormones that regulate appetite and glucose homeostasis. By increasing microbial diversity, GLP-1 agonists create a more resilient gut microbiome capable of resisting pathogenic invasions and maintaining metabolic balance. Thus, by shifting the gut microbiota toward a healthier profile, GLP-1 agonists help disrupt the vicious cycle of obesity-induced gut dysbiosis and inflammation. This review highlights the intricate relationship between obesity, gut microbiota, and GLP-1 agonists, providing valuable insights into their combined role in effective obesity treatment and metabolic health enhancement.

9.
Cureus ; 16(7): e64388, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39131016

RESUMO

Cardiovascular diseases (CVDs), including ischemic heart disease and stroke, are the leading cause of mortality worldwide, causing nearly 20 million deaths annually. Traditional therapies, while effective, have not curbed the rising prevalence of CVDs driven by aging populations and lifestyle factors. This review highlights innovative therapeutic strategies that show promise in improving patient outcomes and transforming cardiovascular care. Emerging pharmacological treatments, such as proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors and sodium-glucose co-transporter 2 (SGLT2) inhibitors, introduce novel mechanisms to complement existing therapies, significantly reducing cardiovascular events and mortality. These advancements emphasize the necessity of ongoing clinical trials and research to discover new therapeutic targets. Advanced biological therapies, including gene therapy, stem cell therapy, and RNA-based treatments, offer groundbreaking potential for repairing and regenerating damaged cardiovascular tissues. Despite being in various stages of clinical validation, early results are promising, suggesting these therapies could fundamentally change the CVD treatment landscape. Innovative medical devices and technologies, such as implantable devices, minimally invasive procedures, and wearable technology, are revolutionizing CVD management. These advancements facilitate early diagnosis, continuous monitoring, and effective treatment, driving care out of hospitals and into homes, improving patient outcomes and reducing healthcare costs. Personalized medicine, driven by genetic profiling and biomarker identification, allows for tailored therapies that enhance treatment efficacy and minimize adverse effects. However, the adoption of these emerging therapies faces significant challenges, including regulatory hurdles, cost and accessibility issues, and ethical considerations. Addressing these barriers and fostering interdisciplinary collaboration are crucial for accelerating the development and implementation of innovative treatments. Integrating emerging therapeutic strategies in cardiovascular care holds immense potential to transform CVD management. By prioritizing future research and overcoming existing challenges, a new era of personalized, effective, and accessible cardiovascular care can be achieved.

10.
Cureus ; 16(8): e67654, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39314570

RESUMO

Gastroesophageal reflux disease (GERD) remains a significant global health concern, with increasing prevalence and a substantial impact on quality of life. This narrative review explores recent advances in our understanding of GERD pathophysiology, diagnosis, and management. The complex interplay of factors contributing to GERD, including lower esophageal sphincter dysfunction, transient sphincter relaxations, and esophageal motility disorders, is discussed. Emerging diagnostic techniques, such as high-resolution manometry and impedance-pH monitoring, have enhanced our ability to accurately identify and characterize GERD. The review highlights the evolving landscape of GERD treatment, from conventional approaches like lifestyle modifications and proton pump inhibitors to novel strategies including potassium-competitive acid blockers, endoscopic therapies, and minimally invasive surgical techniques. The potential role of the microbiome in GERD pathogenesis and as a therapeutic target is examined. The concept of personalized medicine in GERD management is explored, considering genetic factors, biomarkers, and individual patient profiles. Complications of GERD, including erosive esophagitis, Barrett's esophagus, and esophageal adenocarcinoma, are reviewed, emphasizing the importance of early detection and appropriate management. The economic burden and impact on the quality of due to GERD are also addressed. This comprehensive review underscores the multifaceted nature of GERD and the need for a personalized, multidisciplinary approach to its management. It highlights ongoing research efforts and emerging therapies that promise to improve outcomes for GERD patients, while also identifying areas requiring further investigation to optimize diagnosis and treatment strategies.

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