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1.
Front Oncol ; 13: 1180642, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37384298

RESUMO

Objective: Head and neck cancer (HNC) accounts for almost 890,000 new cases per year. Radiotherapy (RT) is used to treat the majority of these patients. A common side-effect of RT is the onset of oral mucositis, which decreases the quality of life and represents the major dose-limiting factor in RT. To understand the origin of oral mucositis, the biological mechanisms post-ionizing radiation (IR) need to be clarified. Such knowledge is valuable to develop new treatment targets for oral mucositis and markers for the early identification of "at-risk" patients. Methods: Primary keratinocytes from healthy volunteers were biopsied, irradiated in vitro (0 and 6 Gy), and subjected to mass spectrometry-based analyses 96 h after irradiation. Web-based tools were used to predict triggered biological pathways. The results were validated in the OKF6 cell culture model. Immunoblotting and mRNA validation was performed and cytokines present in cell culture media post-IR were quantified. Results: Mass spectrometry-based proteomics identified 5879 proteins in primary keratinocytes and 4597 proteins in OKF6 cells. Amongst them, 212 proteins in primary keratinocytes and 169 proteins in OKF6 cells were differentially abundant 96 h after 6 Gy irradiation compared to sham-irradiated controls. In silico pathway enrichment analysis predicted interferon (IFN) response and DNA strand elongation pathways as mostly affected pathways in both cell systems. Immunoblot validations showed a decrease in minichromosome maintenance (MCM) complex proteins 2-7 and an increase in IFN-associated proteins STAT1 and ISG15. In line with affected IFN signalling, mRNA levels of IFNß and interleukin 6 (IL-6) increased significantly following irradiation and also levels of secreted IL-1ß, IL-6, IP-10, and ISG15 were elevated. Conclusion: This study has investigated biological mechanisms in keratinocytes post-in vitro ionizing radiation. A common radiation signature in keratinocytes was identified. The role of IFN response in keratinocytes along with increased levels of pro-inflammatory cytokines and proteins could hint towards a possible mechanism for oral mucositis.

2.
Front Plant Sci ; 13: 966596, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36082293

RESUMO

The non-uniform growth and development of crops within Chinese Solar Greenhouses (CSG) is directly related to the micro-light climate within canopy. In practice, reflective films are used to improve micro-light climate within plant canopy by homogenizing light distribution and so increasing total plant light interception. However, as to our knowledge, the contributions to light distribution within canopy have not been investigated for passive reflector like reflective films. Field experiments dealing with light conditions and growth behavior over time, are complicated to carry out, time-consuming and hard to control, while however, accurate measurements of how reflective films influence the micro-light climate of canopy are an essential step to improve the growth conditions for any crop. Here, we propose a supplementary light strategy using reflective films to improve light distribution within plant canopy. Based on the example of CSG, a 3D greenhouse model including a detailed 3D tomato canopy structure was constructed to simulate the influence of supplementary reflective films to improve micro-light climate. Comparison of measured solar radiation intensity with predicted model data demonstrated that the model could precisely predict light radiation intensity over time with different time points and positions in the greenhouse. A series of reflective film configurations were investigated based on features analysis of light distribution in the tomato canopy on sunny days using the proposed model. The reflective film configuration scheme with the highest impact significantly improved the evenness of horizontal and vertical light distribution in tomato canopy. The strategy provided here can be used to configure reflective films that will enhance light conditions in CSG, which can be applied and extended in different scenarios.

3.
Front Plant Sci ; 13: 906410, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909752

RESUMO

Background: Automated analysis of large image data is highly demanded in high-throughput plant phenotyping. Due to large variability in optical plant appearance and experimental setups, advanced machine and deep learning techniques are required for automated detection and segmentation of plant structures in complex optical scenes. Methods: Here, we present a GUI-based software tool (DeepShoot) for efficient, fully automated segmentation and quantitative analysis of greenhouse-grown shoots which is based on pre-trained U-net deep learning models of arabidopsis, maize, and wheat plant appearance in different rotational side- and top-views. Results: Our experimental results show that the developed algorithmic framework performs automated segmentation of side- and top-view images of different shoots acquired at different developmental stages using different phenotyping facilities with an average accuracy of more than 90% and outperforms shallow as well as conventional and encoder backbone networks in cross-validation tests with respect to both precision and performance time. Conclusion: The DeepShoot tool presented in this study provides an efficient solution for automated segmentation and phenotypic characterization of greenhouse-grown plant shoots suitable also for end-users without advanced IT skills. Primarily trained on images of three selected plants, this tool can be applied to images of other plant species exhibiting similar optical properties.

4.
Cancers (Basel) ; 14(15)2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35954409

RESUMO

Human papillomavirus (HPV)-driven head and neck squamous cell carcinomas (HNSCC) generally have a more favourable prognosis. We hypothesized that HPV-associated HNSCC may be identified by an miRNA-signature according to their specific molecular pathogenesis, and be characterized by a unique transcriptome compared to HPV-negative HNSCC. We performed miRNA expression profiling of two p16/HPV DNA characterized HNSCC cohorts of patients treated by adjuvant radio(chemo)therapy (multicentre DKTK-ROG n = 128, single-centre LMU-KKG n = 101). A linear model predicting HPV status built in DKTK-ROG using lasso-regression was tested in LMU-KKG. LMU-KKG tumours (n = 30) were transcriptome profiled for differential gene expression and miRNA-integration. A 24-miRNA signature predicted HPV-status with 94.53% accuracy (AUC: 0.99) in DKTK-ROG, and 86.14% (AUC: 0.86) in LMU-KKG. The prognostic values of 24-miRNA- and p16/HPV DNA status were comparable. Combining p16/HPV DNA and 24-miRNA status allowed patient sub-stratification and identification of an HPV-associated patient subgroup with impaired overall survival. HPV-positive tumours showed downregulated MAPK, Estrogen, EGFR, TGFbeta, WNT signaling activity. miRNA-mRNA integration revealed HPV-specific signaling pathway regulation, including PD-L1 expression/PD-1 checkpoint pathway in cancer in HPV-associated HNSCC. Integration of clinically established p16/HPV DNA with 24-miRNA signature status improved clinically relevant risk stratification, which might be considered for future clinical decision-making with respect to treatment de-escalation in HPV-associated HNSCC.

5.
Front Plant Sci ; 13: 828252, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242156

RESUMO

Determine the level of significance of planting strategy and plant architecture and how they affect plant physiology and dry matter accumulation within greenhouses is essential to actual greenhouse plant management and breeding. We thus analyzed four planting strategies (plant spacing, furrow distance, row orientation, planting pattern) and eight different plant architectural traits (internode length, leaf azimuth angle, leaf elevation angle, leaf length, leaflet curve, leaflet elevation, leaflet number/area ratio, leaflet length/width ratio) with the same plant leaf area using a formerly developed functional-structural model for a Chinese Liaoshen-solar greenhouse and tomato plant, which used to simulate the plant physiology of light interception, temperature, stomatal conductance, photosynthesis, and dry matter. Our study led to the conclusion that the planting strategies have a more significant impact overall on plant radiation, temperature, photosynthesis, and dry matter compared to plant architecture changes. According to our findings, increasing the plant spacing will have the most significant impact to increase light interception. E-W orientation has better total light interception but yet weaker light uniformity. Changes in planting patterns have limited influence on the overall canopy physiology. Increasing the plant leaflet area by leaflet N/A ratio from what we could observe for a rose the total dry matter by 6.6%, which is significantly better than all the other plant architecture traits. An ideal tomato plant architecture which combined all the above optimal architectural traits was also designed to provide guidance on phenotypic traits selection of breeding process. The combined analysis approach described herein established the causal relationship between investigated traits, which could directly apply to provide management and breeding insights on other plant species with different solar greenhouse structures.

6.
Sensors (Basel) ; 21(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34833515

RESUMO

Automated analysis of small and optically variable plant organs, such as grain spikes, is highly demanded in quantitative plant science and breeding. Previous works primarily focused on the detection of prominently visible spikes emerging on the top of the grain plants growing in field conditions. However, accurate and automated analysis of all fully and partially visible spikes in greenhouse images renders a more challenging task, which was rarely addressed in the past. A particular difficulty for image analysis is represented by leaf-covered, occluded but also matured spikes of bushy crop cultivars that can hardly be differentiated from the remaining plant biomass. To address the challenge of automated analysis of arbitrary spike phenotypes in different grain crops and optical setups, here, we performed a comparative investigation of six neural network methods for pattern detection and segmentation in RGB images, including five deep and one shallow neural network. Our experimental results demonstrate that advanced deep learning methods show superior performance, achieving over 90% accuracy by detection and segmentation of spikes in wheat, barley and rye images. However, spike detection in new crop phenotypes can be performed more accurately than segmentation. Furthermore, the detection and segmentation of matured, partially visible and occluded spikes, for which phenotypes substantially deviate from the training set of regular spikes, still represent a challenge to neural network models trained on a limited set of a few hundreds of manually labeled ground truth images. Limitations and further potential improvements of the presented algorithmic frameworks for spike image analysis are discussed. Besides theoretical and experimental investigations, we provide a GUI-based tool (SpikeApp), which shows the application of pre-trained neural networks to fully automate spike detection, segmentation and phenotyping in images of greenhouse-grown plants.


Assuntos
Redes Neurais de Computação , Melhoramento Vegetal , Grão Comestível , Processamento de Imagem Assistida por Computador , Folhas de Planta
7.
Sci Rep ; 11(1): 16047, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362967

RESUMO

High-throughput root phenotyping in the soil became an indispensable quantitative tool for the assessment of effects of climatic factors and molecular perturbation on plant root morphology, development and function. To efficiently analyse a large amount of structurally complex soil-root images advanced methods for automated image segmentation are required. Due to often unavoidable overlap between the intensity of fore- and background regions simple thresholding methods are, generally, not suitable for the segmentation of root regions. Higher-level cognitive models such as convolutional neural networks (CNN) provide capabilities for segmenting roots from heterogeneous and noisy background structures, however, they require a representative set of manually segmented (ground truth) images. Here, we present a GUI-based tool for fully automated quantitative analysis of root images using a pre-trained CNN model, which relies on an extension of the U-Net architecture. The developed CNN framework was designed to efficiently segment root structures of different size, shape and optical contrast using low budget hardware systems. The CNN model was trained on a set of 6465 masks derived from 182 manually segmented near-infrared (NIR) maize root images. Our experimental results show that the proposed approach achieves a Dice coefficient of 0.87 and outperforms existing tools (e.g., SegRoot) with Dice coefficient of 0.67 by application not only to NIR but also to other imaging modalities and plant species such as barley and arabidopsis soil-root images from LED-rhizotron and UV imaging systems, respectively. In summary, the developed software framework enables users to efficiently analyse soil-root images in an automated manner (i.e. without manual interaction with data and/or parameter tuning) providing quantitative plant scientists with a powerful analytical tool.

8.
Sensors (Basel) ; 21(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33803032

RESUMO

Saturation effects limit the application of vegetation indices (VIs) in dense vegetation areas. The possibility to mitigate them by adopting a negative soil adjustment factor X is addressed. Two leaf area index (LAI) data sets are analyzed using the Google Earth Engine (GEE) for validation. The first one is derived from observations of MODerate resolution Imaging Spectroradiometer (MODIS) from 16 April 2013, to 21 October 2020, in the Apiacás area. Its corresponding VIs are calculated from a combination of Sentinel-2 and Landsat-8 surface reflectance products. The second one is a global LAI dataset with VIs calculated from Landsat-5 surface reflectance products. A linear regression model is applied to both datasets to evaluate four VIs that are commonly used to estimate LAI: normalized difference vegetation index (NDVI), soil adjusted vegetation index (SAVI), transformed SAVI (TSAVI), and enhanced vegetation index (EVI). The optimal soil adjustment factor of SAVI for LAI estimation is determined using an exhaustive search. The Dickey-Fuller test indicates that the time series of LAI data are stable with a confidence level of 99%. The linear regression results stress significant saturation effects in all VIs. Finally, the exhaustive searching results show that a negative soil adjustment factor of SAVI can mitigate the SAVIs' saturation in the Apiacás area (i.e., X = -0.148 for mean LAI = 5.35), and more generally in areas with large LAI values (e.g., X = -0.183 for mean LAI = 6.72). Our study further confirms that the lower boundary of the soil adjustment factor can be negative and that using a negative soil adjustment factor improves the computation of time series of LAI.


Assuntos
Folhas de Planta , Solo , Modelos Lineares , Imagens de Satélites
9.
Plant Methods ; 16: 95, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670387

RESUMO

BACKGROUND: Automated segmentation of large amount of image data is one of the major bottlenecks in high-throughput plant phenotyping. Dynamic optical appearance of developing plants, inhomogeneous scene illumination, shadows and reflections in plant and background regions complicate automated segmentation of unimodal plant images. To overcome the problem of ambiguous color information in unimodal data, images of different modalities can be combined to a virtual multispectral cube. However, due to motion artefacts caused by the relocation of plants between photochambers the alignment of multimodal images is often compromised by blurring artifacts. RESULTS: Here, we present an approach to automated segmentation of greenhouse plant images which is based on co-registration of fluorescence (FLU) and of visible light (VIS) camera images followed by subsequent separation of plant and marginal background regions using different species- and camera view-tailored classification models. Our experimental results including a direct comparison with manually segmented ground truth data show that images of different plant types acquired at different developmental stages from different camera views can be automatically segmented with the average accuracy of 93 % ( S D = 5 % ) using our two-step registration-classification approach. CONCLUSION: Automated segmentation of arbitrary greenhouse images exhibiting highly variable optical plant and background appearance represents a challenging task to data classification techniques that rely on detection of invariances. To overcome the limitation of unimodal image analysis, a two-step registration-classification approach to combined analysis of fluorescent and visible light images was developed. Our experimental results show that this algorithmic approach enables accurate segmentation of different FLU/VIS plant images suitable for application in fully automated high-throughput manner.

10.
Int J Radiat Oncol Biol Phys ; 106(2): 320-328, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669562

RESUMO

PURPOSE: Oral mucositis (OM) is a frequent and painful sequela of concomitant chemoradiation (CRT) used for the treatment of head and neck cancer (HNC) for which there is no effective intervention. This randomized, placebo-controlled study evaluated the efficacy of a novel, mucoadhesive topical tablet formulation of clonidine in mitigating CRT-induced OM in patients with HNC. METHODS AND MATERIALS: Patients with HNC undergoing adjuvant radiation therapy (60-66 Gy; 5 × 1.8-2.2 Gy/wk) with concomitant platinum-based chemotherapy received daily local clonidine at 50 µg (n = 56), 100 µg (n = 65), or placebo (n = 62) via a topical mucobuccal tablet starting 1 to 3 days before and continuing during treatment. The primary endpoint was the incidence of severe OM (severe OM [SOM], World Health Organization grade 3/4). RESULTS: SOM developed in 45% versus 60% (P = .06) of patients treated with clonidine compared with placebo and occurred for the first time at 60 Gy as opposed to 48 Gy (median; hazard ratio, 0.75 [95% confidence interval, 0.484-1.175], P = .21); median time to onset was 45 versus 36 days. Opioid analgesic use, mean patient-reported mouth and throat soreness, and CRT compliance were not significantly different between treatment arms. Adverse events were reported in 90.8% versus 98.4%, nausea in 49.6% versus 71.0%, dysphagia in 32.8% versus 48.4%, and reversible hypotension in 6.7% versus 1.6% of patients on clonidine versus placebo, respectively. CONCLUSIONS: Although the primary endpoint was not met, the positive trends of OM-associated outcomes suggest that the novel mucoadhesive tablet delivery of clonidine might favorably affect the course and severity of CRT-induced SOM and support further evaluation.


Assuntos
Quimiorradioterapia/efeitos adversos , Clonidina/administração & dosagem , Neoplasias de Cabeça e Pescoço/radioterapia , Protetores contra Radiação/administração & dosagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Estomatite/prevenção & controle , Administração Bucal , Adulto , Idoso , Analgésicos Opioides/administração & dosagem , Clonidina/efeitos adversos , Intervalos de Confiança , Transtornos de Deglutição/etiologia , Método Duplo-Cego , Esquema de Medicação , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Protetores contra Radiação/efeitos adversos , Dosagem Radioterapêutica , Estomatite/etiologia , Comprimidos , Adulto Jovem
11.
Sci Rep ; 9(1): 19674, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31873104

RESUMO

Quantitative characterization of root system architecture and its development is important for the assessment of a complete plant phenotype. To enable high-throughput phenotyping of plant roots efficient solutions for automated image analysis are required. Since plants naturally grow in an opaque soil environment, automated analysis of optically heterogeneous and noisy soil-root images represents a challenging task. Here, we present a user-friendly GUI-based tool for semi-automated analysis of soil-root images which allows to perform an efficient image segmentation using a combination of adaptive thresholding and morphological filtering and to derive various quantitative descriptors of the root system architecture including total length, local width, projection area, volume, spatial distribution and orientation. The results of our semi-automated root image segmentation are in good conformity with the reference ground-truth data (mean dice coefficient = 0.82) compared to IJ_Rhizo and GiAroots. Root biomass values calculated with our tool within a few seconds show a high correlation (Pearson coefficient = 0.8) with the results obtained using conventional, pure manual segmentation approaches. Equipped with a number of adjustable parameters and optional correction tools our software is capable of significantly accelerating quantitative analysis and phenotyping of soil-, agar- and washed root images.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Raízes de Plantas/anatomia & histologia , Algoritmos , Arabidopsis/anatomia & histologia , Gráficos por Computador , Ensaios de Triagem em Larga Escala , Fenótipo , Software , Solo , Interface Usuário-Computador
12.
PLoS One ; 14(9): e0221203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31568494

RESUMO

With the introduction of multi-camera systems in modern plant phenotyping new opportunities for combined multimodal image analysis emerge. Visible light (VIS), fluorescence (FLU) and near-infrared images enable scientists to study different plant traits based on optical appearance, biochemical composition and nutrition status. A straightforward analysis of high-throughput image data is hampered by a number of natural and technical factors including large variability of plant appearance, inhomogeneous illumination, shadows and reflections in the background regions. Consequently, automated segmentation of plant images represents a big challenge and often requires an extensive human-machine interaction. Combined analysis of different image modalities may enable automatisation of plant segmentation in "difficult" image modalities such as VIS images by utilising the results of segmentation of image modalities that exhibit higher contrast between plant and background, i.e. FLU images. For efficient segmentation and detection of diverse plant structures (i.e. leaf tips, flowers), image registration techniques based on feature point (FP) matching are of particular interest. However, finding reliable feature points and point pairs for differently structured plant species in multimodal images can be challenging. To address this task in a general manner, different feature point detectors should be considered. Here, a comparison of seven different feature point detectors for automated registration of VIS and FLU plant images is performed. Our experimental results show that straightforward image registration using FP detectors is prone to errors due to too large structural difference between FLU and VIS modalities. We show that structural image enhancement such as background filtering and edge image transformation significantly improves performance of FP algorithms. To overcome the limitations of single FP detectors, combination of different FP methods is suggested. We demonstrate application of our enhanced FP approach for automated registration of a large amount of FLU/VIS images of developing plant species acquired from high-throughput phenotyping experiments.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Plantas/anatomia & histologia , Algoritmos , Clorofila/metabolismo , Fluorescência , Humanos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Iluminação , Fenótipo , Fotografação/métodos , Desenvolvimento Vegetal , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Plantas/metabolismo
13.
Plant Methods ; 15: 44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31168314

RESUMO

With the introduction of high-throughput multisensory imaging platforms, the automatization of multimodal image analysis has become the focus of quantitative plant research. Due to a number of natural and technical reasons (e.g., inhomogeneous scene illumination, shadows, and reflections), unsupervised identification of relevant plant structures (i.e., image segmentation) represents a nontrivial task that often requires extensive human-machine interaction. Registration of multimodal plant images enables the automatized segmentation of 'difficult' image modalities such as visible light or near-infrared images using the segmentation results of image modalities that exhibit higher contrast between plant and background regions (such as fluorescent images). Furthermore, registration of different image modalities is essential for assessment of a consistent multiparametric plant phenotype, where, for example, chlorophyll and water content as well as disease- and/or stress-related pigmentation can simultaneously be studied at a local scale. To automatically register thousands of images, efficient algorithmic solutions for the unsupervised alignment of two structurally similar but, in general, nonidentical images are required. For establishment of image correspondences, different algorithmic approaches based on different image features have been proposed. The particularity of plant image analysis consists, however, of a large variability of shapes and colors of different plants measured at different developmental stages from different views. While adult plant shoots typically have a unique structure, young shoots may have a nonspecific shape that can often be hardly distinguished from the background structures. Consequently, it is not clear a priori what image features and registration techniques are suitable for the alignment of various multimodal plant images. Furthermore, dynamically measured plants may exhibit nonuniform movements that require application of nonrigid registration techniques. Here, we investigate three common techniques for registration of visible light and fluorescence images that rely on finding correspondences between (i) feature-points, (ii) frequency domain features, and (iii) image intensity information. The performance of registration methods is validated in terms of robustness and accuracy measured by a direct comparison with manually segmented images of different plants. Our experimental results show that all three techniques are sensitive to structural image distortions and require additional preprocessing steps including structural enhancement and characteristic scale selection. To overcome the limitations of conventional approaches, we develop an iterative algorithmic scheme, which allows it to perform both rigid and slightly nonrigid registration of high-throughput plant images in a fully automated manner.

14.
Clin Cancer Res ; 25(5): 1505-1516, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30171046

RESUMO

PURPOSE: Human papillomavirus (HPV)-negative head and neck squamous cell carcinoma (HNSCC) is associated with unfavorable prognosis, while independent prognostic markers remain to be defined. EXPERIMENTAL DESIGN: We retrospectively performed miRNA expression profiling. Patients were operated for locally advanced HPV-negative HNSCC and had received radiochemotherapy in eight different hospitals (DKTK-ROG; n = 85). Selection fulfilled comparable demographic, treatment, and follow-up characteristics. Findings were validated in an independent single-center patient sample (LMU-KKG; n = 77). A prognostic miRNA signature was developed for freedom from recurrence and tested for other endpoints. Recursive-partitioning analysis was performed on the miRNA signature, tumor and nodal stage, and extracapsular nodal spread. Technical validation used qRT-PCR. An miRNA-mRNA target network was generated and analyzed. RESULTS: For DKTK-ROG and LMU-KKG patients, the median follow-up was 5.1 and 5.3 years, and the 5-year freedom from recurrence rate was 63.5% and 75.3%, respectively. A five-miRNA signature (hsa-let-7g-3p, hsa-miR-6508-5p, hsa-miR-210-5p, hsa-miR-4306, and hsa-miR-7161-3p) predicted freedom from recurrence in DKTK-ROG [hazard ratio (HR) 4.42; 95% confidence interval (CI), 1.98-9.88, P < 0.001], which was confirmed in LMU-KKG (HR 4.24; 95% CI, 1.40-12.81, P = 0.005). The signature also predicted overall survival (HR 3.03; 95% CI, 1.50-6.12, P = 0.001), recurrence-free survival (HR 3.16; 95% CI, 1.65-6.04, P < 0.001), and disease-specific survival (HR 5.12; 95% CI, 1.88-13.92, P < 0.001), all confirmed in LMU-KKG data. Adjustment for relevant covariates maintained the miRNA signature predicting all endpoints. Recursive-partitioning analysis of both samples combined classified patients into low (n = 17), low-intermediate (n = 80), high-intermediate (n = 48), or high risk (n = 17) for recurrence (P < 0.001). CONCLUSIONS: The five-miRNA signature is a strong and independent prognostic factor for disease recurrence and survival of patients with HPV-negative HNSCC.See related commentary by Clump et al., p. 1441.


Assuntos
Biomarcadores Tumorais , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/mortalidade , MicroRNAs/genética , Transcriptoma , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Papillomaviridae , Infecções por Papillomavirus/complicações , Prognóstico , Modelos de Riscos Proporcionais , Resultado do Tratamento
15.
Front Plant Sci ; 9: 1519, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464765

RESUMO

Modern facilities for high-throughput phenotyping provide plant scientists with a large amount of multi-modal image data. Combination of different image modalities is advantageous for image segmentation, quantitative trait derivation, and assessment of a more accurate and extended plant phenotype. However, visible light (VIS), fluorescence (FLU), and near-infrared (NIR) images taken with different cameras from different view points in different spatial resolutions exhibit not only relative geometrical transformations but also considerable structural differences that hamper a straightforward alignment and combined analysis of multi-modal image data. Conventional techniques of image registration are predominantly tailored to detection of relative geometrical transformations between two otherwise identical images, and become less accurate when applied to partially similar optical scenes. Here, we focus on a relatively new technical problem of FLU/VIS plant image registration. We present a framework for automated alignment of FLU/VIS plant images which is based on extension of the phase correlation (PC) approach - a frequency domain technique for image alignment, which relies on detection of a phase shift between two Fourier-space transforms. Primarily tailored to detection of affine image transformations between two structurally identical images, PC is known to be sensitive to structural image distortions. We investigate effects of image preprocessing and scaling on accuracy of image registration and suggest an integrative algorithmic scheme which allows to overcome shortcomings of conventional single-step PC by application to non-identical multi-modal images. Our experimental tests with FLU/VIS images of different plant species taken on different phenotyping facilities at different developmental stages, including difficult cases such as small plant shoots of non-specific shape and non-uniformly moving leaves, demonstrate improved performance of our extended PC approach within the scope of high-throughput plant phenotyping.

16.
Ann Bot ; 122(4): 669-676, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-29905760

RESUMO

Background and Aims: Currently, functional-structural plant models (FSPMs) mostly resort to static descriptions of leaf spectral characteristics, which disregard the influence of leaf physiological changes over time. In many crop species, including soybean, these time-dependent physiological changes are of particular importance as leaf chlorophyll content changes with leaf age and vegetative nitrogen is remobilized to the developing fruit during pod filling. Methods: PROSPECT, a model developed to estimate leaf biochemical composition from remote sensing data, is well suited to allow a dynamic approximation of leaf spectral characteristics in terms of leaf composition. In this study, measurements of the chlorophyll content index (CCI) were linked to leaf spectral characteristics within the 400-800 nm range by integrating the PROSPECT model into a soybean FSPM alongside a wavelength-specific light model. Key Results: Straightforward links between the CCI and the parameters of the PROSPECT model allowed us to estimate leaf spectral characteristics with high accuracy using only the CCI as an input. After integration with an FSPM, this allowed digital reconstruction of leaf spectral characteristics on the scale of both individual leaves and the whole canopy. As a result, accurate simulations of light conditions within the canopy were obtained. Conclusions: The proposed approach resulted in a very accurate representation of leaf spectral properties, based on fast and simple measurements of the CCI. Integration of accurate leaf spectral characteristics into a soybean FSPM leads to a better, dynamic understanding of the actual perceived light within the canopy in terms of both light quantity and quality.


Assuntos
Clorofila/análise , Glycine max/fisiologia , Modelos Biológicos , Nitrogênio/metabolismo , Simulação por Computador , Luz , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Tecnologia de Sensoriamento Remoto , Glycine max/anatomia & histologia , Glycine max/efeitos da radiação , Fatores de Tempo
17.
Ann Bot ; 121(5): 833-848, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29293870

RESUMO

Background and Aims: Predicting both plant water status and leaf gas exchange under various environmental conditions is essential for anticipating the effects of climate change on plant growth and productivity. This study developed a functional-structural grapevine model which combines a mechanistic understanding of stomatal function and photosynthesis at the leaf level (i.e. extended Farqhuhar-von Caemmerer-Berry model) and the dynamics of water transport from soil to individual leaves (i.e. Tardieu-Davies model). Methods: The model included novel features that account for the effects of xylem embolism (fPLC) on leaf hydraulic conductance and residual stomatal conductance (g0), variable root and leaf hydraulic conductance, and the microclimate of individual organs. The model was calibrated with detailed datasets of leaf photosynthesis, leaf water potential, xylem sap abscisic acid (ABA) concentration and hourly whole-plant transpiration observed within a soil drying period, and validated with independent datasets of whole-plant transpiration under both well-watered and water-stressed conditions. Key Results: The model well captured the effects of radiation, temperature, CO2 and vapour pressure deficit on leaf photosynthesis, transpiration, stomatal conductance and leaf water potential, and correctly reproduced the diurnal pattern and decline of water flux within the soil drying period. In silico analyses revealed that decreases in g0 with increasing fPLC were essential to avoid unrealistic drops in leaf water potential under severe water stress. Additionally, by varying the hydraulic conductance along the pathway (e.g. root and leaves) and changing the sensitivity of stomatal conductance to ABA and leaf water potential, the model can produce different water use behaviours (i.e. iso- and anisohydric). Conclusions: The robust performance of this model allows for modelling climate effects from individual plants to fields, and for modelling plants with complex, non-homogenous canopies. In addition, the model provides a basis for future modelling efforts aimed at describing the physiology and growth of individual organs in relation to water status.


Assuntos
Modelos Biológicos , Fotossíntese , Transpiração Vegetal , Vitis/fisiologia , Água/metabolismo , Ácido Abscísico/análise , Transporte Biológico , Mudança Climática , Desidratação , Reguladores de Crescimento de Plantas/análise , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , Estômatos de Plantas/anatomia & histologia , Estômatos de Plantas/fisiologia , Solo/química , Temperatura , Pressão de Vapor , Vitis/anatomia & histologia , Xilema/anatomia & histologia , Xilema/fisiologia
18.
Biom J ; 59(6): 1339-1351, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28692743

RESUMO

Radiation therapy in patients with head and neck cancer has a toxic effect on mucosa, the soft tissue in and around the mouth. Hence mucositis is a serious common side effect and is a condition characterized by pain and inflammation of the surface of the mucosa. Although the mucosa recovers during breaks of and following the radiotherapy course, the recovery will depend on the type of tissue involved and on its location. We present a novel flexible multivariate random effects proportional odds model that takes account of the longitudinal course of oral mucositis at different mouth sites and of the radiation dosage (in terms of cumulative dose). The model is an extension of the proportional odds model that is used for ordinal response variables. Our model includes the ordinal multivariate response of the mucositis score by site, random intercepts for individuals, and a nonlinear function of cumulative radiation dose. The model allows to test whether sensitivity differs by mouth sites after having adjusted for site-specific cumulative radiation dose. The model also allows to check whether and how the (nonlinear) effect of site-specific dose differs by site. We fit the model to longitudinal patient data from a prospective observation and find that after adjusting for cumulative dose, upper, lower lips, and mouth floor are associated with the lowest mucositis scores and hard and soft palate are associated with the highest mucositis scores. This implies the possibility that tissues at different mouth sites differ in their sensitivity to the toxic effect of radiation.


Assuntos
Modelos Estatísticos , Modelos de Riscos Proporcionais , Radioterapia/efeitos adversos , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Análise Multivariada , Processos Estocásticos
19.
Front Plant Sci ; 8: 313, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28377775

RESUMO

Functional-structural plant modeling (FSPM) is a fast and dynamic method to predict plant growth under varying environmental conditions. Temperature is a primary factor affecting the rate of plant development. In the present study, we used three different temperature treatments (10/14°C, 18/22°C, and 26/30°C) to test the effect of temperature on growth and development of rapeseed (Brassica napus L.) seedlings. Plants were sampled at regular intervals (every 3 days) to obtain growth data during the length of the experiment (1 month in total). Total leaf dry mass, leaf area, leaf mass per area (LMA), width-length ratio, and the ratio of petiole length to leaf blade length (PBR), were determined and statistically analyzed, and contributed to a morphometric database. LMA under high temperature was significantly smaller than LMA under medium and low temperature, while leaves at high temperature were significantly broader. An FSPM of rapeseed seedlings featuring a growth function used for leaf extension and biomass accumulation was implemented by combining measurement with literature data. The model delivered new insights into growth and development dynamics of winter oilseed rape seedlings. The present version of the model mainly focuses on the growth of plant leaves. However, future extensions of the model could be used in practice to better predict plant growth in spring and potential cold damage of the crop.

20.
Data Brief ; 8: 501-5, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27358911

RESUMO

Saliva as major human body fluid may act as an indicator of oral disease status. Oral mucositis is a common and often treatment-limiting side effect of radiotherapy for head and neck cancer patients. In this dataset, we provide the complete proteome dataset (raw and search files) of the patients at baseline of radiotherapy treatment in patients undergoing radiotherapy analyzed by nano liquid chromatography coupled to mass spectrometry (LC-MS/MS). In the data set, 5323 tryptic peptides were identified which can be assigned to 487 distinct proteins (≥2 peptides). The MS data have been deposited to the ProteomeXchange ("ProteomeXchange provides globally coordinated proteomics data submission and dissemination" [1]) via the PRIDE partner repository with the dataset identifier PRIDE: PXD003230. The data are associated with the previously published work, "Differences in the whole saliva baseline proteome profile associated with development of oral mucositis in head and neck cancer patients undergoing radiotherapy" [2].

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