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In plants, growth and defence are controlled by many molecular pathways that are antagonistic to one another. This results in a 'growth-defence trade-off', where plants temporarily reduce growth in response to pests or diseases. Due to this antagonism, genetic variants that improve resistance often reduce growth and vice versa. Therefore, in natural populations, the most disease resistant individuals are often the slowest growing. In crops, slow growth may translate into a yield penalty, but resistance is essential for protecting yield in the presence of disease. Therefore, plant breeders must balance these traits to ensure optimal yield potential and yield stability. In crops, both qualitative and quantitative disease resistance are often linked with genetic variants that cause yield penalties, but this is not always the case. Furthermore, both crop yield and disease resistance are complex traits influenced by many aspects of the plant's physiology, morphology and environment, and the relationship between the molecular growth-defence trade-off and disease resistance-yield antagonism is not well-understood. In this article, we highlight research from the last 2 years on the molecular mechanistic basis of the antagonism between defence and growth. We then discuss the interaction between disease resistance and crop yield from a breeding perspective, outlining the complexity and nuances of this relationship and where research can aid practical methods for simultaneous improvement of yield potential and disease resistance.
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Produtos Agrícolas , Resistência à Doença , Doenças das Plantas , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Resistência à Doença/genética , Doenças das Plantas/imunologia , Doenças das Plantas/genética , Melhoramento VegetalRESUMO
Sample preparation can present a significant hurdle within single particle cryo-electron microscopy (cryoEM), resulting in issues with reproducibility, data quality or an inability to visualise the sample. There are several factors which can influence this, including sample or buffer composition, grid type, route of sample preparation and interactions with the air-water interface (AWI). Here, we review some of the current routes for sample preparation and the associated challenges. We discuss a range of approaches for overcoming these challenges, such as minimising the grid preparation time, surfactants, grid type and biochemical approaches such as nanomagnetic beads. Finally, we discuss how a set of commercially available protein samples may serve as a benchmark suite for future technologies. This provides a route to compare techniques' abilities not just to generate high-resolution structures but also to overcome the challenges traditionally associated with cryoEM. As the field continues to produce new approaches to sample preparation and we start to better understand the underlying principles behind the behaviour of proteins within a thin film and in response to different environments, especially grid composition, it is hoped that more universal solutions can be provided that make the intractable systems tractable, improve resolution and, importantly, speed up data collection and reduce the currently required dataset sizes.
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Microscopia Crioeletrônica , Proteínas , Microscopia Crioeletrônica/métodos , Proteínas/química , Manejo de Espécimes/métodosRESUMO
BACKGROUND: Acute unreconstructible 3- or 4-part proximal humerus fractures can be treated with hemiarthroplasty or reverse polarity shoulder arthroplasty. Randomized trials using implants from multiple different companies or uncemented implants have found superior results with reverse polarity arthroplasty. AIMS: This study aims to determine whether cemented reverse polarity arthroplasty produces a superior outcome compared to cemented hemiarthroplasty using one implant system in patients aged 65 years and over at 12 months follow-up as measured with the Constant score. METHODS: A prospective patient and assessor blinded multicenter randomized controlled trial was conducted of shoulder hemiarthroplasty or reverse polarity arthroplasty in patients aged 65 years and older with acute 3- and 4-part proximal humerus fracture not amenable to osteosynthesis. The primary outcome was the Constant score at 12 months with total follow-up to 24 months. Block randomization by site was undertaken using random number generation and sealed envelopes. Power analysis indicated that 17 patients were required in each arm to achieve 80% power with an alpha-value of 5%. Secondary outcome measures were the difference in the mean Constant Score, Quick Disabilities of the Arm Shoulder and Hand Questionnaire (QuickDASH), Oxford Shoulder Score (OSS), American Shoulder and Elbow Surgeons (ASES) Score and EQ5D-5L up to two years; differences in complication rate at one and two years; differences in revision and implant failure at one and two years. RESULTS: 18 patients were randomized to hemiarthroplasty and 18 to reverse polarity arthroplasty across 4 sites. The primary outcome as measured by the Constant score at 12 months was better in the reverse polarity shoulder arthroplasty (RSA) group (Mean 51.1, s.d. 14.9) compared to the hemiarthroplasty (HA) group (mean 35.0, s.d. 13.5) (p=0.004). No significant difference was reported at 24 months but this may be due to high rates of attrition (22%). The mean EQ-5D-5L patient rated health status score was significantly higher in the RSA group compared to the HA group at 12 months. One hemiarthroplasty was revised due to implant uncoupling and one reverse polarity shoulder replacement was revised due to instability. No other complications were recorded. DISCUSSION: Treatment of unreconstructible 3- or 4-part proximal humerus fractures with reverse polarity shoulder arthroplasty results in a superior outcome compared to shoulder hemiarthroplasty at 12 months measured with the Constant score with no increased risk of failure up to 24 months in patients age 65 years and over. High attrition rates are observed in this older population due to cognitive decline and death from other causes.
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PURPOSE: Over 30,000 hip hemiarthroplasties for neck of femur fractures are performed annually in the United Kingdom (UK). The national recommendation is via the lateral approach, to reduce the risk of dislocation, with the potential expense of reduced function and mobility post-operatively. Muscle-sparing approaches, such as SPAIRE (sparing piriformis and internus repairing externus), have been invented to address the issue of dislocation. METHODS: We performed a retrospective data collection at a single center with a high annual volume of hip hemiarthroplasties over 12 months. All patients who had hip hemiarthroplasty as their primary treatment were included. Patients who passed away and were non-ambulant before their surgery were excluded from the study. Our primary outcome was the dislocation rate and secondary outcomes were the time to mobilization after surgery and the duration of surgery. Statistical analysis was performed using XLSTAT software. RESULTS: We identified 194 cases, and these were divided into 3 groups based on the surgical approach: SPAIRE (n = 43), lateral (n = 97), and posterior (n = 54). Groups had similar demographics and a minimum 3-month follow-up after surgery. There were no dislocations in the SPAIRE group, whereas the dislocation rate for the other 2 groups was 2.5% in the lateral and 9.1% in the posterior groups at 6 months post-surgery. There was an earlier return to mobility in the SPAIRE (1.4 day) compared to the 2 other groups ( 2 days and 2.6 days). Average surgical times were very similar among all 3 groups (74 min vs. 79 min vs. 71 min). CONCLUSION: The SPAIRE approach seems to be safe and provides a low risk of dislocation and good post-operative function for patients undergoing hip hemiarthroplasties.
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We report the case of a 71-year-old man who presented 2 years following renal transplantation with diffuse, unilateral cytomegalovirus retinitis five weeks after receiving an intravitreal dexamethasone implant device for the management of central retinal vein occlusion. Examination of the left eye showed diffuse retinal hemorrhages, attenuated and tortuous retinal vessels, and superior retinal whitening. The patient was successfully treated with serial intravitreal foscarnet injections and oral valganciclovir with disease regression observed by 12 weeks after presentation. The patient's visual acuity and examination remained stable at 9-months follow-up.
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BACKGROUND: The aim of this study was to investigate the effects of cardiac rehabilitation on health markers and performance outcomes among diabetic and nondiabetic patients with coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI). METHODS: One hundred and ninety-seven patients with PCI and CABG, who attended phase 2 cardiac rehabilitation, were included in the study. Patient data were separated by cardiac diagnosis, (PCI and CABG), diabetes category (diabetic and nondiabetic), number of sessions attended (12-24 or 25-36), and time (pre- to post-test). The Duke Activity Score Index and Patient Health Questionnaire-9 questionnaires and measurements for total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, and, if diabetic, A1c and fasting blood glucose, were taken at baseline and upon completion of the program. RESULTS: High-density lipoprotein (p < 0.001), diastolic blood pressure (p = 0.004), Duke Activity Score Index questionnaire (p < 0.001), Patient Health Questionnaire-9 (p < 0.001), and A1c (p = 0.003) significantly improved from pre- to post-testing. Total cholesterol (p < 0.001) and low-density lipoprotein (p < 0.001) for the 25-36 nondiabetic PCI group significantly decreased. Triglycerides decreased for all 12-24 session groups (p = 0.015). Fasting blood glucose significantly decreased (p = 0.037) for the 12-24 PCI group with diabetes. No significant interactions were found for systolic blood pressure and body weight. CONCLUSION: Cardiac rehabilitation resulted in significant improvements in the lipid panel, diastolic blood pressure, and questionnaire results, regardless of the number of sessions attended. However, no significant benefits for systolic blood pressure were observed.
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Holocentric karyotypes are assumed to rapidly evolve through chromosome fusions and fissions due to the diffuse nature of their centromeres. Here, we took advantage of the recent availability of a chromosome-scale reference genome for Rhynchospora breviuscula, a model species of this holocentric genus, and developed the first set of oligo-based barcode probes for a holocentric plant. These probes were applied to 13 additional species of the genus, aiming to investigate the evolutionary dynamics driving the karyotype evolution in Rhynchospora. The two sets of probes were composed of 27,392 (green) and 23,968 (magenta) oligonucleotides (45-nt long), and generated 15 distinct FISH signals as a unique barcode pattern for the identification of all five chromosome pairs of the R. breviuscula karyotype. Oligo-FISH comparative analyzes revealed different types of rearrangements, such as fusions, fissions, putative inversions and translocations, as well as genomic duplications among the analyzed species. Two rounds of whole genome duplication (WGD) were demonstrated in R. pubera, but both analyzed accessions differed in the complex chain of events that gave rise to its large, structurally diploidized karyotypes with 2n = 10 or 12. Considering the phylogenetic relationships and divergence time of the species, the specificity and synteny of the probes were maintained up to species with a divergence time of ~25 My. However, karyotype divergence in more distant species hindered chromosome mapping and the inference of specific events. This barcoding system is a powerful tool to study chromosomal variations and genomic evolution in holocentric chromosomes of Rhynchospora species.
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The knowledge of minority and majority charge carrier properties enables controlling the performance of solar cells, transistors, detectors, sensors, and LEDs. Here, we developed the constant light induced magneto transport method which resolves electron and hole mobility, lifetime, diffusion coefficient and length, and quasi-Fermi level splitting. We demonstrate the implication of the constant light induced magneto transport for silicon and metal halide perovskite films. We resolve the transport properties of electrons and holes predicting the material's effectiveness for solar cell application without making the full device. The accessibility of fourteen material parameters paves the way for in-depth exploration of causal mechanisms limiting the efficiency and functionality of material structures. To demonstrate broad applicability, we further characterized twelve materials with drift mobilities spanning from 10-3 to 103 cm2V-1s-1 and lifetimes varying between 10-9 and 10-3 seconds. The universality of our method its potential to advance optoelectronic devices in various technological fields.
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Terapia com Prótons , Prótons , Humanos , Espécies Reativas de Oxigênio , Elétrons , Dosagem RadioterapêuticaRESUMO
Foi realizado um levantamento florístico de três remanescentes de floresta montana localizados na Mata Atlântica do sul da Bahia. Durante os anos de 2004 a 2008 foram feitas coletas periódicas de material botânico, principalmente ao longo de trilhas no interior dos fragmentos das áreas: Reserva Serra da Pedra Lascada - SPL, Reserva Serra das Lontras - SLO e Reserva Particular do Patrimônio Natural Serra Bonita - SBO. A riqueza florística em cada área foi comparada entre si e com outras áreas de Mata Atlântica na Bahia e no Sudeste do Brasil. Foi registrado um total de 1.129 espécies em 467 gêneros e 124 famílias. O hábito arbóreo representou 46,9 por cento das espécies, seguido de herbáceas (20,1 por cento), epífitas (19,5 por cento) e trepadeiras (13,5 por cento). As famílias Araceae, Asteraceae, Bromeliaceae, Fabaceae, Lauraceae, Melastomataceae, Myrtaceae, Orchidaceae, Piperaceae, Poaceae, Rubiaceae e Solanaceae apresentaram a maior riqueza florística nas três áreas em conjunto. O gênero Psychotria (Rubiaceae) apresentou o maior número de espécies em todas as áreas (21 spp.), destacando-se também Miconia (20 spp.), Solanum (20 spp.), Piper (19 spp.), Ocotea (16 spp.), Leandra (16 spp.), Peperomia (15 spp.) e Myrcia (14 spp.). Os resultados confirmam a elevada riqueza de angiospermas no sul da Bahia e evidenciam, pela primeira vez, a ocorrência de espécies características de regiões montanhosas da Mata Atlântica do Sudeste do Brasil nessa região.
A floristic study of three areas of montane Atlantic forest in southern Bahia, Brazil, was carried out. From 2004 to 2008 regular botanical collections were made, principally along trails in the interior of the forest fragments at: the Reserva Serra da Pedra Lascada (SPL), the Reserva Serra das Lontras (SLO) and the Reserva Particular do Patrimônio Natural Serra Bonita (SBO). The species richness of each area was compared to that of the other two, and together to other areas of Atlantic coastal forest in Bahia and southeastern Brazil. For all three areas, a total of 1129 species in 467 genera and 124 families were found. Trees represented 46.9 percent of the species, followed by herbs (20.1 percent), epiphytes (19.5 percent), and vines and lianas (13.5 percent). The families Araceae, Asteraceae, Bromeliaceae, Fabaceae, Lauraceae, Melastomataceae, Myrtaceae, Orchidaceae, Piperaceae, Poaceae, Rubiaceae, and Solanaceae showed the highest species richness for the three areas together. The genus Psychotria (Rubiaceae) had the highest number of species for all three areas (21 spp.), followed by Miconia (20 spp.), Solanum (20 spp.), Piper (19 spp.), Ocotea (16 spp.), Leandra (16 spp.), Peperomia (15 spp.), and Myrcia (14 spp.). The results confirm the high species diversity of angiosperms in southern Bahia and demonstrate for the first time the presence of species characteristic of montane regions of southeastern Brazil in this region.