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1.
New Phytol ; 241(6): 2435-2447, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38214462

RESUMO

Radiation use efficiency (RUE) is a key crop adaptation trait that quantifies the potential amount of aboveground biomass produced by the crop per unit of solar energy intercepted. But it is unclear why elite maize and grain sorghum hybrids differ in their RUE at the crop level. Here, we used a non-traditional top-down approach via canopy photosynthesis modelling to identify leaf-level photosynthetic traits that are key to differences in crop-level RUE. A novel photosynthetic response measurement was developed and coupled with use of a Bayesian model fitting procedure, incorporating a C4 leaf photosynthesis model, to infer cohesive sets of photosynthetic parameters by simultaneously fitting responses to CO2 , light, and temperature. Statistically significant differences between leaf photosynthetic parameters of elite maize and grain sorghum hybrids were found across a range of leaf temperatures, in particular for effects on the quantum yield of photosynthesis, but also for the maximum enzymatic activity of Rubisco and PEPc. Simulation of diurnal canopy photosynthesis predicted that the leaf-level photosynthetic low-light response and its temperature dependency are key drivers of the performance of crop-level RUE, generating testable hypotheses for further physiological analysis and bioengineering applications.


Assuntos
Fotossíntese , Luz Solar , Temperatura , Teorema de Bayes , Fotossíntese/fisiologia , Folhas de Planta , Zea mays
2.
Plant J ; 93(2): 338-354, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29161754

RESUMO

Sorghum bicolor is a drought tolerant C4 grass used for the production of grain, forage, sugar, and lignocellulosic biomass and a genetic model for C4 grasses due to its relatively small genome (approximately 800 Mbp), diploid genetics, diverse germplasm, and colinearity with other C4 grass genomes. In this study, deep sequencing, genetic linkage analysis, and transcriptome data were used to produce and annotate a high-quality reference genome sequence. Reference genome sequence order was improved, 29.6 Mbp of additional sequence was incorporated, the number of genes annotated increased 24% to 34 211, average gene length and N50 increased, and error frequency was reduced 10-fold to 1 per 100 kbp. Subtelomeric repeats with characteristics of Tandem Repeats in Miniature (TRIM) elements were identified at the termini of most chromosomes. Nucleosome occupancy predictions identified nucleosomes positioned immediately downstream of transcription start sites and at different densities across chromosomes. Alignment of more than 50 resequenced genomes from diverse sorghum genotypes to the reference genome identified approximately 7.4 M single nucleotide polymorphisms (SNPs) and 1.9 M indels. Large-scale variant features in euchromatin were identified with periodicities of approximately 25 kbp. A transcriptome atlas of gene expression was constructed from 47 RNA-seq profiles of growing and developed tissues of the major plant organs (roots, leaves, stems, panicles, and seed) collected during the juvenile, vegetative and reproductive phases. Analysis of the transcriptome data indicated that tissue type and protein kinase expression had large influences on transcriptional profile clustering. The updated assembly, annotation, and transcriptome data represent a resource for C4 grass research and crop improvement.


Assuntos
Variação Genética/genética , Genoma de Planta/genética , Sorghum/genética , Transcriptoma , Análise por Conglomerados , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Mutação INDEL , Anotação de Sequência Molecular , Nucleossomos/genética , Polimorfismo de Nucleotídeo Único/genética
3.
Plant Physiol ; 172(2): 823-834, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27528244

RESUMO

Dissecting the genetic basis of complex traits is aided by frequent and nondestructive measurements. Advances in range imaging technologies enable the rapid acquisition of three-dimensional (3D) data from an imaged scene. A depth camera was used to acquire images of sorghum (Sorghum bicolor), an important grain, forage, and bioenergy crop, at multiple developmental time points from a greenhouse-grown recombinant inbred line population. A semiautomated software pipeline was developed and used to generate segmented, 3D plant reconstructions from the images. Automated measurements made from 3D plant reconstructions identified quantitative trait loci for standard measures of shoot architecture, such as shoot height, leaf angle, and leaf length, and for novel composite traits, such as shoot compactness. The phenotypic variability associated with some of the quantitative trait loci displayed differences in temporal prevalence; for example, alleles closely linked with the sorghum Dwarf3 gene, an auxin transporter and pleiotropic regulator of both leaf inclination angle and shoot height, influence leaf angle prior to an effect on shoot height. Furthermore, variability in composite phenotypes that measure overall shoot architecture, such as shoot compactness, is regulated by loci underlying component phenotypes like leaf angle. As such, depth imaging is an economical and rapid method to acquire shoot architecture phenotypes in agriculturally important plants like sorghum to study the genetic basis of complex traits.


Assuntos
Folhas de Planta/genética , Brotos de Planta/genética , Locos de Características Quantitativas/genética , Sorghum/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Biologia Computacional/métodos , Grão Comestível/anatomia & histologia , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Brotos de Planta/anatomia & histologia , Brotos de Planta/crescimento & desenvolvimento , Reprodutibilidade dos Testes , Sorghum/anatomia & histologia , Sorghum/crescimento & desenvolvimento
4.
Cochrane Database Syst Rev ; 5: CD009781, 2017 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-28516471

RESUMO

BACKGROUND: Traumatic corneal abrasions are relatively common and there is a lack of consensus about analgesia in their management. It is therefore important to document the clinical efficacy and safety profile of topical ophthalmic non-steroidal anti-inflammatory drugs (NSAIDs) in the management of traumatic corneal abrasions. OBJECTIVES: To identify and evaluate all randomised controlled trials (RCTs) comparing the use of topical NSAIDs with placebo or any alternative analgesic interventions in adults with traumatic corneal abrasions (including corneal abrasions arising from foreign body removal), to reduce pain, and its effects on healing time. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 2), MEDLINE Ovid (1946 to 30 March 2017), Embase Ovid (1947 to 30 March 2017), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 30 March 2017), OpenGrey (System for Information on Grey Literature in Europe) (www.opengrey.eu/); searched 30 March 2017, ZETOC (1993 to 30 March 2017), the ISRCTN registry (www.isrctn.com/editAdvancedSearch); searched 30 March 2017, ClinicalTrials.gov (www.clinicaltrials.gov); searched 30 March 2017 and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 30 March 2017. We did not use any date or language restrictions in the electronic searches for trials.We checked the reference lists of identified trials to search for further potentially relevant studies. SELECTION CRITERIA: RCTs comparing topical NSAIDs to placebo or any alternative analgesic interventions in adults with traumatic corneal abrasions. DATA COLLECTION AND ANALYSIS: Two review authors independently performed data extraction and assessed risks of bias in the included studies. We rated the certainty of the evidence using GRADE. MAIN RESULTS: We included nine studies that met the inclusion criteria, reporting data on 637 participants.The studies took place in the UK, USA, Israel, Italy, France and Portugal. These studies compared five types of topical NSAIDs (0.1% indomethacin, 0.03% flurbiprofen, 0.5% ketorolac, 1% indomethacin, 0.1% diclofenac) to control (consisting of standard care and in four studies used placebo eye drops). Overall, the studies were at an unclear or high risk of bias (particularly selection and reporting bias). None of the included studies reported the primary outcome measures of this review, namely participant-reported pain intensity reduction of 30% or more or 50% or more at 24 hours. Four trials, that included data on 481 participants receiving NSAIDs or control (placebo/standard care), reported on the use of 'rescue' analgesia at 24 hours as a proxy measure of pain control. Topical NSAIDs were associated with a reduction in the need for oral analgesia compared with control (risk ratio (RR) 0.46, 95% confidence interval (CI) 0.34 to 0.61; low-certainty evidence). Approximately 4 out of 10 people in the control group used rescue analgesia at 24 hours. No data were available on the use of analgesia at 48 or 72 hours.One trial (28 participants) reported on the proportion of abrasions healed after 24 and 48 hours. These outcomes were similar in both arms of the trial. (at 24 hours RR 1.00 (0.81 to 1.23); at 48 hours RR 1.00 (0.88 to 1.14); low-certainty evidence). In the control group nine out of 10 abrasions were healed within 24 hours and all were healed by 48 hours. Complications of corneal abrasions were reported in 6 studies (609 participants) and were infrequently reported (4 complications, 1 in NSAID groups (recurrent corneal erosion) and 3 in control groups (2 recurrent corneal erosions and 1 corneal abscess), very low-certainty evidence). Possible drug-related adverse events (AEs) were reported in two trials (163 participants), with the number of adverse events low (4 AEs, 3 in NSAID group, including discomfort/photophobia on instillation, conjunctival hyperaemia and urticaria, and 1 in the control group, corneal abscess) very low-certainty evidence. AUTHORS' CONCLUSIONS: The findings of the included studies do not provide strong evidence to support the use of topical NSAIDs in traumatic corneal abrasions. This is important, since NSAIDs are associated with a higher cost compared to oral analgesics. None of the trials addressed our primary outcome measure of participant-reported pain intensity reduction of 30% or more or 50% or more at 24 hours.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Lesões da Córnea/tratamento farmacológico , Administração Tópica , Anti-Inflamatórios não Esteroides/efeitos adversos , Lesões da Córnea/complicações , Diclofenaco/administração & dosagem , Flurbiprofeno/administração & dosagem , Humanos , Indometacina/administração & dosagem , Cetorolaco/administração & dosagem , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Cicatrização
5.
Basic Res Cardiol ; 110(1): 456, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25480109

RESUMO

The ß1-adrenergic antagonist metoprolol improves cardiac function in animals and patients with chronic heart failure, isolated mitral regurgitation (MR), and ischemic heart disease, though the molecular mechanisms remain incompletely understood. Metoprolol has been reported to upregulate cardiac expression of ß3-adrenergic receptors (ß3AR) in animal models. Myocardial ß3AR signaling via neuronal nitric oxide synthase (nNOS) activation has recently emerged as a cardioprotective pathway. We tested whether chronic ß1-adrenergic blockade with metoprolol enhances myocardial ß3AR coupling with nitric oxide-stimulated cyclic guanosine monophosphate (ß3AR/NO-cGMP) signaling in the MR-induced, volume-overloaded heart. We compared the expression, distribution, and inducible activation of ß3AR/NO-cGMP signaling proteins within myocardial membrane microdomains in dogs (canines) with surgically induced MR, those also treated with metoprolol succinate (MR+ßB), and unoperated controls. ß3AR mRNA transcripts, normalized to housekeeping gene RPLP1, increased 4.4 × 10(3)- and 3.2 × 10(2)-fold in MR and MR+ßB hearts, respectively, compared to Control. Cardiac ß3AR expression was increased 1.4- and nearly twofold in MR and MR+ßB, respectively, compared to Control. ß3AR was detected within caveolae-enriched lipid rafts (Cav3(+)LR) and heavy density, non-lipid raft membrane (NLR) across all groups. However, in vitro selective ß3AR stimulation with BRL37344 (BRL) triggered cGMP production within only NLR of MR+ßB. BRL induced Ser (1412) phosphorylation of nNOS within NLR of MR+ßB, but not Control or MR, consistent with detection of NLR-specific ß3AR/NO-cGMP coupling. Treatment with metoprolol prevented MR-associated oxidation of NO biosensor soluble guanylyl cyclase (sGC) within NLR. Metoprolol therapy also prevented MR-induced relocalization of sGCß1 subunit away from caveolae, suggesting preserved NO-sGC-cGMP signaling, albeit without coupling to ß3AR, within MR+ßB caveolae. Chronic ß1-blockade is associated with myocardial ß3AR/NO-cGMP coupling in a microdomain-specific fashion. Our canine study suggests that microdomain-targeted enhancement of myocardial ß3AR/NO-cGMP signaling may explain, in part, ß1-adrenergic antagonist-mediated preservation of cardiac function in the volume-overloaded heart.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 1/farmacologia , GMP Cíclico/fisiologia , Insuficiência da Valva Mitral/tratamento farmacológico , Óxido Nítrico/fisiologia , Receptores Adrenérgicos beta 3/fisiologia , Transdução de Sinais/fisiologia , Antagonistas de Receptores Adrenérgicos beta 1/uso terapêutico , Animais , Doença Crônica , Cães , Etanolaminas/farmacologia , Guanilato Ciclase/metabolismo , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/fisiologia , Metoprolol/farmacologia , Insuficiência da Valva Mitral/fisiopatologia , Óxido Nítrico Sintase Tipo I/fisiologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Guanilil Ciclase Solúvel , Função Ventricular Esquerda
6.
J Exp Bot ; 65(13): 3479-89, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24958898

RESUMO

Sorghum is emerging as an excellent genetic model for the design of C4 grass bioenergy crops. Annual energy Sorghum hybrids also serve as a source of biomass for bioenergy production. Elucidation of Sorghum's flowering time gene regulatory network, and identification of complementary alleles for photoperiod sensitivity, enabled large-scale generation of energy Sorghum hybrids for testing and commercial use. Energy Sorghum hybrids with long vegetative growth phases were found to accumulate more than twice as much biomass as grain Sorghum, owing to extended growing seasons, greater light interception, and higher radiation use efficiency. High biomass yield, efficient nitrogen recycling, and preferential accumulation of stem biomass with low nitrogen content contributed to energy Sorghum's elevated nitrogen use efficiency. Sorghum's integrated genetics-genomics-breeding platform, diverse germplasm, and the opportunity for annual testing of new genetic designs in controlled environments and in multiple field locations is aiding fundamental discovery, and accelerating the improvement of biomass yield and optimization of composition for biofuels production. Recent advances in wide hybridization between Sorghum and other C4 grasses could allow the deployment of improved genetic designs of annual energy Sorghums in the form of wide-hybrid perennial crops. The current trajectory of energy Sorghum genetic improvement indicates that it will be possible to sustainably produce biofuels from C4 grass bioenergy crops that are cost competitive with petroleum-based transportation fuels.


Assuntos
Genoma de Planta/genética , Genômica , Sorghum/genética , Biocombustíveis , Biomassa , Cruzamento , Produtos Agrícolas , Metabolismo Energético , Flores/genética , Flores/metabolismo , Flores/efeitos da radiação , Fenótipo , Filogenia , Poaceae/genética , Poaceae/metabolismo , Poaceae/efeitos da radiação , Sorghum/metabolismo , Sorghum/efeitos da radiação , Fatores de Tempo
7.
Sci Rep ; 14(1): 7612, 2024 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-38556523

RESUMO

Europe imports large amounts of soybean that are predominantly used for livestock feed, mainly sourced from Brazil, USA and Argentina. In addition, the demand for GM-free soybean for human consumption is project to increase. Soybean has higher protein quality and digestibility than other legumes, along with high concentrations of isoflavones, phytosterols and minerals that enhance the nutritional value as a human food ingredient. Here, we examine the potential to increase soybean production across Europe for livestock feed and direct human consumption, and review possible effects on the environment and human health. Simulations and field data indicate rainfed soybean yields of 3.1 ± 1.2 t ha-1 from southern UK through to southern Europe (compared to a 3.5 t ha-1 average from North America). Drought-prone southern regions and cooler northern regions require breeding to incorporate stress-tolerance traits. Literature synthesized in this work evidenced soybean properties important to human nutrition, health, and traits related to food processing compared to alternative protein sources. While acknowledging the uncertainties inherent in any modelling exercise, our findings suggest that further integrating soybean into European agriculture could reduce GHG emissions by 37-291 Mt CO2e year-1 and fertiliser N use by 0.6-1.2 Mt year-1, concurrently improving human health and nutrition.


Assuntos
Fabaceae , Glycine max , Humanos , Melhoramento Vegetal , Agricultura , Europa (Continente)
8.
J Neurosci ; 32(12): 4004-16, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22442067

RESUMO

Previous studies have shown that modulation of the receptor-mediated cannabinoid system during neuroinflammation can produce potent neuroprotective and anti-inflammatory effects. However, in this context, little is known about how selective activation of the cannabinoid type-2 receptor (CB2R) affects the activated state of the brain endothelium and blood-brain barrier (BBB) function. Using human brain tissues and primary human brain microvascular endothelial cells (BMVECs), we demonstrate that the CB2R is highly upregulated during inflammatory insult. We then examined whether the CB2R agonists could attenuate inflammatory responses at the BBB using a mouse model of LPS-induced encephalitis and highly selective CB2R agonists. Visualization by intravital microscopy revealed that administration of JWH133 [(6aR,10aR)-3-(1,1-dimethylbutyl)-6a,7,10,10a-tetrahydro-6,6,9-trimethyl-6H-dibenzo[b,d]pyran] or a novel resorcinol-based compound, O-1966 (1-[4-(1,1-dimethyl-heptyl)-2,6-dimethoxy-phenyl]-3-methyl-cyclohexanol), greatly attenuated leukocyte adhesion in surface pial vessels and in deep ascending cortical postcapillary venules. BBB permeability assessments with small and large fluorescent tracers showed that CB2R agonists were effective at preventing barrier leakiness after LPS administration. To determine whether the effects by CB2R agonists on barrier protection are not only due to the CB2R modulation of immune cell function, we tested the agonists in vitro with barrier-forming primary BMVECs. Remarkably, the addition of CB2R agonist increased transendothelial electrical resistance and increased the amount of tight junction protein present in membrane fractions. Furthermore, CB2R agonists decreased the induction of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 surface expression in BMVECs exposed to various proinflammatory mediators. Together, these results suggest that pharmacological CB2R ligands offer a new strategy for BBB protection during neuroinflammation.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Encefalite/patologia , Células Endoteliais/fisiologia , Leucócitos/fisiologia , Receptor CB2 de Canabinoide/metabolismo , Animais , Anisóis/farmacologia , Anisóis/uso terapêutico , Barreira Hematoencefálica/efeitos dos fármacos , Canfanos/farmacologia , Canabinoides/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Permeabilidade Capilar/fisiologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Células Cultivadas , Cicloexanóis , Dextranos/metabolismo , Modelos Animais de Doenças , Impedância Elétrica , Encefalite/induzido quimicamente , Endotélio/metabolismo , Citometria de Fluxo , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos/efeitos adversos , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfoproteínas/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Pirazóis/farmacologia , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/deficiência , Estatísticas não Paramétricas , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Proteína da Zônula de Oclusão-1
9.
Front Plant Sci ; 14: 1172359, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37389290

RESUMO

Introduction: Dynamic crop growth models are an important tool to predict complex traits, like crop yield, for modern and future genotypes in their current and evolving environments, as those occurring under climate change. Phenotypic traits are the result of interactions between genetic, environmental, and management factors, and dynamic models are designed to generate the interactions producing phenotypic changes over the growing season. Crop phenotype data are becoming increasingly available at various levels of granularity, both spatially (landscape) and temporally (longitudinal, time-series) from proximal and remote sensing technologies. Methods: Here we propose four phenomenological process models of limited complexity based on differential equations for a coarse description of focal crop traits and environmental conditions during the growing season. Each of these models defines interactions between environmental drivers and crop growth (logistic growth, with implicit growth restriction, or explicit restriction by irradiance, temperature, or water availability) as a minimal set of constraints without resorting to strongly mechanistic interpretations of the parameters. Differences between individual genotypes are conceptualized as differences in crop growth parameter values. Results: We demonstrate the utility of such low-complexity models with few parameters by fitting them to longitudinal datasets from the simulation platform APSIM-Wheat involving in silico biomass development of 199 genotypes and data of environmental variables over the course of the growing season at four Australian locations over 31 years. While each of the four models fits well to particular combinations of genotype and trial, none of them provides the best fit across the full set of genotypes by trials because different environmental drivers will limit crop growth in different trials and genotypes in any specific trial will not necessarily experience the same environmental limitation. Discussion: A combination of low-complexity phenomenological models covering a small set of major limiting environmental factors may be a useful forecasting tool for crop growth under genotypic and environmental variation.

10.
Circulation ; 124(11 Suppl): S18-26, 2011 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-21911811

RESUMO

BACKGROUND: Experimentally, exogenous administration of recombinant stromal cell-derived factor-1α (SDF) enhances neovasculogenesis and cardiac function after myocardial infarction. Smaller analogs of SDF may provide translational advantages including enhanced stability and function, ease of synthesis, lower cost, and potential modulated delivery via engineered biomaterials. In this study, computational protein design was used to create a more efficient evolution of the native SDF protein. METHODS AND RESULTS: Protein structure modeling was used to engineer an SDF polypeptide analog (engineered SDF analog [ESA]) that splices the N-terminus (activation and binding) and C-terminus (extracellular stabilization) with a diproline segment designed to limit the conformational flexibility of the peptide backbone and retain the relative orientation of these segments observed in the native structure of SDF. Endothelial progenitor cells (EPCs) in ESA gradient, assayed by Boyden chamber, showed significantly increased migration compared with both SDF and control gradients. EPC receptor activation was evaluated by quantification of phosphorylated AKT, and cells treated with ESA yielded significantly greater phosphorylated AKT levels than SDF and control cells. Angiogenic growth factor assays revealed a distinct increase in angiopoietin-1 expression in the ESA- and SDF-treated hearts. In addition, CD-1 mice (n=30) underwent ligation of the left anterior descending coronary artery and peri-infarct intramyocardial injection of ESA, SDF-1α, or saline. At 2 weeks, echocardiography demonstrated a significant gain in ejection fraction, cardiac output, stroke volume, and fractional area change in mice treated with ESA compared with controls. CONCLUSIONS: Compared with native SDF, a novel engineered SDF polypeptide analog (ESA) more efficiently induces EPC migration and improves post-myocardial infarction cardiac function and thus offers a more clinically translatable neovasculogenic therapy.


Assuntos
Proteínas Angiogênicas/química , Proteínas Angiogênicas/farmacologia , Quimiocina CXCL12/química , Quimiocina CXCL12/farmacologia , Biologia Computacional/métodos , Neovascularização Fisiológica/efeitos dos fármacos , Engenharia de Proteínas/métodos , Proteínas Angiogênicas/uso terapêutico , Animais , Débito Cardíaco/efeitos dos fármacos , Débito Cardíaco/fisiologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Células Cultivadas , Quimiocina CXCL12/uso terapêutico , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiologia , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Modelos Animais , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/prevenção & controle , Neovascularização Fisiológica/fisiologia , Ratos , Ratos Wistar , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/fisiologia
11.
Surg Endosc ; 26(3): 727-31, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22042583

RESUMO

BACKGROUND: This study aimed to demonstrate the effectiveness of using a multifunctional miniature in vivo robotic platform to perform a single-incision colectomy. Standard laparoscopic techniques require multiple ports. A miniature robotic platform to be inserted completely into the peritoneal cavity through a single incision has been designed and built. The robot can be quickly repositioned, thus enabling multiquadrant access to the abdominal cavity. METHODS: The miniature in vivo robotic platform used in this study consists of a multifunctional robot and a remote surgeon interface. The robot is composed of two arms with shoulder and elbow joints. Each forearm is equipped with specialized interchangeable end effectors (i.e., graspers and monopolar electrocautery). RESULTS: Five robotic colectomies were performed in a porcine model. For each procedure, the robot was completely inserted into the peritoneal cavity, and the surgeon manipulated the user interface to control the robot to perform the colectomy. The robot mobilized the colon from its lateral retroperitoneal attachments and assisted in the placement of a standard stapler to transect the sigmoid colon. This objective was completed for all five colectomies without any complications. CONCLUSIONS: The adoption of both laparoscopic and single-incision colectomies currently is constrained by the inadequacies of existing instruments. The described multifunctional robot provides a platform that overcomes existing limitations by operating completely within one incision in the peritoneal cavity and by improving visualization and dexterity. By repositioning the small robot to the area of the colon to be mobilized, the ability of the surgeon to perform complex surgical tasks is improved. Furthermore, the success of the robot in performing a completely in vivo colectomy suggests the feasibility of using this robotic platform to perform other complex surgeries through a single incision.


Assuntos
Colectomia/instrumentação , Laparoscopia/instrumentação , Miniaturização , Robótica/instrumentação , Animais , Colectomia/métodos , Desenho de Equipamento , Laparoscopia/métodos , Sus scrofa
12.
Circulation ; 122(11 Suppl): S107-17, 2010 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-20837901

RESUMO

BACKGROUND: Myocardial ischemia causes cardiomyocyte death, adverse ventricular remodeling, and ventricular dysfunction. Endothelial progenitor cells (EPCs) have been shown to ameliorate this process, particularly when activated with stromal cell-derived factor-1α (SDF), known to be the most potent EPC chemokine. We hypothesized that implantation of a tissue-engineered extracellular matrix (ECM) scaffold seeded with EPCs primed with SDF could induce borderzone neovasculogenesis, prevent adverse geometric remodeling, and preserve ventricular function after myocardial infarction. METHODS AND RESULTS: Lewis rats (n=82) underwent left anterior descending artery ligation to induce myocardial infarction. EPCs were isolated, characterized, and cultured on a vitronectin/collagen scaffold and primed with SDF to generate the activated EPC matrix (EPCM). EPCM was sutured to the anterolateral left ventricular wall, which included the region of ischemia. Control animals received sutures but no EPCM. Additional groups underwent application of the ECM alone, ECM primed with SDF (ECM+SDF), and ECM seeded with EPCs but not primed with SDF (ECM+SDF). At 4 weeks, borderzone myocardial tissue demonstrated increased levels of vascular endothelial growth factor in the EPCM group. When compared to controls, Vessel density as assessed by immunohistochemical microscopy was significantly increased in the EPCM group (4.1 versus 6.2 vessels/high-powered field; P<0.001), and microvascular perfusion measured by lectin microangiography was enhanced 4-fold (0.7% versus 2.7% vessel volume/section volume; P=0.04). Comparisons to additional groups also showed a significantly improved vasculogenic response in the EPCM group. Ventricular geometry and scar fraction assessed by digital planimetric analysis of sectioned hearts exhibited significantly preserved left ventricular internal diameter (9.7 mm versus 8.6 mm; P=0.005) and decreased infarct scar formation expressed as percent of total section area (16% versus 7%; P=0.002) when compared with all other groups. In addition, EPCM animals showed a significant preservation of function as measured by echocardiography, pressure-volume conductance, and Doppler flow. CONCLUSIONS: Extracellular matrix seeded with EPCs primed with SDF induces borderzone neovasculogenesis, attenuates adverse ventricular remodeling, and preserves ventricular function after myocardial infarction.


Assuntos
Quimiocina CXCL12/farmacologia , Células Endoteliais/citologia , Matriz Extracelular , Infarto do Miocárdio/terapia , Neovascularização Fisiológica/efeitos dos fármacos , Células-Tronco/citologia , Engenharia Tecidual/métodos , Animais , Células Cultivadas , Colágeno , Modelos Animais de Doenças , Humanos , Masculino , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Ratos , Ratos Endogâmicos Lew , Disfunção Ventricular/patologia , Disfunção Ventricular/terapia , Vitronectina
13.
Eukaryot Cell ; 9(10): 1549-56, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20675579

RESUMO

Light signaling pathways and circadian clocks are inextricably linked and have profound effects on behavior in most organisms. Here, we used chromatin immunoprecipitation (ChIP) sequencing to uncover direct targets of the Neurospora crassa circadian regulator White Collar Complex (WCC). The WCC is a blue-light receptor and the key transcription factor of the circadian oscillator. It controls a transcriptional network that regulates ∼20% of all genes, generating daily rhythms and responses to light. We found that in response to light, WCC binds to hundreds of genomic regions, including the promoters of previously identified clock- and light-regulated genes. We show that WCC directly controls the expression of 24 transcription factor genes, including the clock-controlled adv-1 gene, which controls a circadian output pathway required for daily rhythms in development. Our findings provide links between the key circadian activator and effectors in downstream regulatory pathways.


Assuntos
Relógios Circadianos , Regulação Fúngica da Expressão Gênica , Luz , Neurospora crassa/fisiologia , Transdução de Sinais , Fatores de Transcrição/metabolismo , Imunoprecipitação da Cromatina , Ritmo Circadiano , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Redes Reguladoras de Genes , Genoma Fúngico/genética , Sequenciamento de Nucleotídeos em Larga Escala , Neurospora crassa/genética , Neurospora crassa/metabolismo , Reação em Cadeia da Polimerase , Fatores de Transcrição/genética
14.
Heart Lung Circ ; 19(11): 644-54, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20719564

RESUMO

PURPOSE: Post-myocardial infarction heart failure is a major health concern with limited therapy. Molecular revascularisation utilising granulocyte-macrophage colony stimulating factor (GMCSF) mediated endothelial progenitor cell (EPC) upregulation and stromal cell derived factor-1α (SDF) mediated myocardial EPC chemokinesis, may prevent myocardial loss and adverse remodelling. Vasculogenesis, viability, and haemodynamic improvements following therapy were investigated. PROCEDURES: Lewis rats (n=91) underwent LAD ligation and received either intramyocardial SDF and subcutaneous GMCSF or saline injections at the time of infarction. Molecular and haemodynamic assessments were performed at pre-determined time points following ligation. FINDINGS: SDF/GMCSF therapy upregulated EPC density as shown by flow cytometry (0.12±0.02% vs. 0.06±0.01% circulating lymphocytes, p=0.005), 48hours following infarction. A marked increase in perfusion was evident eight weeks after therapy, utilising confocal angiography (5.02±1.7×10(-2)µm(3)blood/µm(3)myocardial tissue vs. 2.03±0.710(-2)µm(3)blood/µm(3)myocardial tissue, p=0.00004). Planimetric analysis demonstrated preservation of wall thickness (0.98±0.09mm vs. 0.67±0.06mm, p=0.003) and ventricular diameter (7.81±0.99mm vs. 9.41±1.1mm, p=0.03). Improved haemodynamic function was evidenced by echocardiography and PV analysis (ejection fraction: 56.4±18.1% vs. 25.3±15.6%, p=0.001; pre-load adjusted maximal power: 6.6±2.6mW/µl(2) vs. 2.7±1.4mW/µl(2), p=0.01). CONCLUSION: Neovasculogenic therapy with GMCSF-mediated EPC upregulation and SDF-mediated EPC chemokinesis maybe an effective therapy for infarct modulation and preservation of myocardial function following acute myocardial infarction.


Assuntos
Quimiocina CXCL12/uso terapêutico , Células Endoteliais/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Coração/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Infarto do Miocárdio/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos , Animais , Apoptose , Quimiocina CXCL12/farmacologia , Ecocardiografia , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Ventrículos do Coração/anatomia & histologia , Células-Tronco Hematopoéticas/fisiologia , Masculino , Modelos Animais , Miocárdio/patologia , Ratos , Ratos Endogâmicos Lew , Regulação para Cima
15.
Front Plant Sci ; 8: 335, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28377779

RESUMO

Bioenergy sorghum is targeted for production in water-limited annual cropland therefore traits that improve plant water capture, water use efficiency, and resilience to water deficit are necessary to maximize productivity. A crop modeling framework, APSIM, was adapted to predict the growth and biomass yield of energy sorghum and to identify potentially useful traits for crop improvement. APSIM simulations of energy sorghum development and biomass accumulation replicated results from field experiments across multiple years, patterns of rainfall, and irrigation schemes. Modeling showed that energy sorghum's long duration of vegetative growth increased water capture and biomass yield by ~30% compared to short season crops in a water-limited production region. Additionally, APSIM was extended to enable modeling of VPD-limited transpiration traits that reduce crop water use under high vapor pressure deficits (VPDs). The response of transpiration rate to increasing VPD was modeled as a linear response until a VPD threshold was reached, at which the slope of the response decreases, representing a range of responses to VPD observed in sorghum germplasm. Simulation results indicated that the VPD-limited transpiration trait is most beneficial in hot and dry regions of production where crops are exposed to extended periods without rainfall during the season or to a terminal drought. In these environments, slower but more efficient transpiration increases biomass yield and prevents or delays the exhaustion of soil water and onset of leaf senescence. The VPD-limited transpiration responses observed in sorghum germplasm increased biomass accumulation by 20% in years with lower summer rainfall, and the ability to drastically reduce transpiration under high VPD conditions could increase biomass by 6% on average across all years. This work indicates that the productivity and resilience of bioenergy sorghum grown in water-limited environments could be further enhanced by development of genotypes with optimized VPD-limited transpiration traits and deployment of these crops in water limited growing environments. The energy sorghum model and VPD-limited transpiration trait implementation are made available to simulate performance in other target environments.

16.
Sci Rep ; 7(1): 4616, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28676627

RESUMO

Sorghum is an important C4 grass crop grown for grain, forage, sugar, and bioenergy production. While tall, late flowering landraces are commonly grown in Africa, short early flowering varieties were selected in US grain sorghum breeding programs to reduce lodging and to facilitate machine harvesting. Four loci have been identified that affect stem length (Dw1-Dw4). Subsequent research showed that Dw3 encodes an ABCB1 auxin transporter and Dw1 encodes a highly conserved protein involved in the regulation of cell proliferation. In this study, Dw2 was identified by fine-mapping and further confirmed by sequencing the Dw2 alleles in Dwarf Yellow Milo and Double Dwarf Yellow Milo, the progenitor genotypes where the recessive allele of dw2 originated. The Dw2 locus was determined to correspond to Sobic.006G067700, a gene that encodes a protein kinase that is homologous to KIPK, a member of the AGCVIII subgroup of the AGC protein kinase family in Arabidopsis.


Assuntos
Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Sorghum/crescimento & desenvolvimento , Mapeamento Cromossômico , Genótipo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/crescimento & desenvolvimento , Locos de Características Quantitativas , Análise de Sequência de DNA , Sorghum/genética
17.
ACS Appl Mater Interfaces ; 8(30): 19494-506, 2016 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-27414167

RESUMO

Emulsion-based, resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) has been demonstrated as an alternative technique to deposit conjugated polymer films for photovoltaic applications; yet, a fundamental understanding of how the emulsion target characteristics translate into film properties and solar cell performance is unclear. Such understanding is crucial to enable the rational improvement of organic solar cell (OSC) efficiency and to realize the expected advantages of emulsion-based RIR-MAPLE for OSC fabrication. In this paper, the effect of the primary solvent used in the emulsion target is studied, both experimentally and theoretically, and it is found to determine the conjugated polymer cluster size in the emulsion as well as surface roughness and internal morphology of resulting polymer films. By using a primary solvent with low solubility-in-water and low vapor pressure, the surface roughness of deposited P3HT and PCPDTBT polymer films was reduced to 10 nm, and the efficiency of P3HT:PC61BM OSCs was increased to 3.2% (∼100 times higher compared to the first MAPLE OSC demonstration [ Caricato , A. P. ; Appl. Phys. Lett. 2012 , 100 , 073306 ]). This work unveils the mechanism of polymer film formation using emulsion-based RIR-MAPLE and provides insight and direction to determine the best ways to take advantage of the emulsion target approach to control film properties for different applications.

18.
G3 (Bethesda) ; 5(4): 655-65, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25681258

RESUMO

Recent advances in variant calling made available in the Genome Analysis Toolkit (GATK) enable the use of validated single-nucleotide polymorphisms and indels to improve variant calling. However, large collections of variants for this purpose often are unavailable to research communities. We introduce a workflow to generate reliable collections of single-nucleotide polymorphisms and indels by leveraging available genomic resources to inform variant calling using the GATK. The workflow is demonstrated for the crop plant Sorghum bicolor by (i) generating an initial set of variants using reduced representation sequence data from an experimental cross and association panels, (ii) using the initial variants to inform variant calling from whole-genome sequence data of resequenced individuals, and (iii) using variants identified from whole-genome sequence data for recalibration of the reduced representation sequence data. The reliability of variants called with the workflow is verified by comparison with genetically mappable variants from an independent sorghum experimental cross. Comparison with a recent sorghum resequencing study shows that the workflow identifies an additional 1.62 million high-confidence variants from the same sequence data. Finally, the workflow's performance is validated using Arabidopsis sequence data, yielding variant call sets with 95% sensitivity and 99% positive predictive value. The Recalibration and Interrelation of genomic sequence data with the GATK (RIG) workflow enables the GATK to accurately identify genetic variation in organisms lacking validated variant resources.


Assuntos
Genômica/métodos , Software , Algoritmos , Arabidopsis/genética , Sequência de Bases , Calibragem , Genoma de Planta , Genômica/normas , Polimorfismo de Nucleotídeo Único
19.
Genetics ; 201(3): 1229-38, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26323882

RESUMO

The efficiency with which a plant intercepts solar radiation is determined primarily by its architecture. Understanding the genetic regulation of plant architecture and how changes in architecture affect performance can be used to improve plant productivity. Leaf inclination angle, the angle at which a leaf emerges with respect to the stem, is a feature of plant architecture that influences how a plant canopy intercepts solar radiation. Here we identify extensive genetic variation for leaf inclination angle in the crop plant Sorghum bicolor, a C4 grass species used for the production of grain, forage, and bioenergy. Multiple genetic loci that regulate leaf inclination angle were identified in recombinant inbred line populations of grain and bioenergy sorghum. Alleles of sorghum dwarf-3, a gene encoding a P-glycoprotein involved in polar auxin transport, are shown to change leaf inclination angle by up to 34° (0.59 rad). The impact of heritable variation in leaf inclination angle on light interception in sorghum canopies was assessed using functional-structural plant models and field experiments. Smaller leaf inclination angles caused solar radiation to penetrate deeper into the canopy, and the resulting redistribution of light is predicted to increase the biomass yield potential of bioenergy sorghum by at least 3%. These results show that sorghum leaf angle is a heritable trait regulated by multiple loci and that genetic variation in leaf angle can be used to modify plant architecture to improve sorghum crop performance.


Assuntos
Variação Genética , Folhas de Planta , Sorghum/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Agricultura , Sorghum/crescimento & desenvolvimento
20.
J Am Soc Cytopathol ; 3(6): 303-308, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-31051720

RESUMO

INTRODUCTION: DOG1 is a calcium-activated chloride channel protein that may have a potential role in secretory cells of salivary glands and tumors derived from them. Its role in cytologic specimens is not well documented. This study was performed to evaluate its utility in separating acinic cell carcinoma (AciCC) from other closely related differential diagnoses on cytologic samples. In addition, an immunohistochemical panel consisting of DOG1, p63, and S100 protein to assist in the subclassification of these salivary gland neoplasms with oncocytic differentiation was also investigated. MATERIALS AND METHODS: Thirty-one fine-needle aspiration cell blocks (CBs) of oncocytic salivary gland neoplasms (16 Warthin tumors [WTs], 10 AciCCs, 3 mucoepidermoid carcinomas [MECs], and 2 oncocytomas [ONCs]), and 75 salivary gland resections (7 WTs, 27 AciCCs, 36 MECs, 2 high-grade adenocarcinomas, 2 ONCs, 1 papillary cystadenoma) were immunostained for DOG1, p63, and S100. RESULTS: DOG1 and p63 were very useful in distinguishing AciCC from WT on CB, because 100% of WTs were DOG1-negative and 87.5% were p63-positive, whereas 70% of AciCCs were DOG1-positive and 100% were p63-negative. The resection results correlated with those on CBs: 100% of WTs were DOG1-negative and 86% were p63-positive, whereas 93% of AciCCs were DOG1-positive and 89% were p63-negative. S100 and DOG1 were negative in both WTs and ONCs, with <10% S100 positivity in AciCCs. CONCLUSIONS: DOG1 was very helpful in separating AciCC from WT, MEC, and ONC. In summary, an immunohistochemical panel including DOG1, p63, and S100 can significantly improve the accuracy of diagnosing oncocytic salivary gland neoplasms on CBs.

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