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Theiler's murine encephalomyelitis virus (TMEV) causes a chronic demyelinating disease similar to multiple sclerosis in mice. Although sialic acids have been shown to be essential for TMEV attachment to the host, the surface receptor has not been identified. While type I interferons play a pivotal role in the elimination of the chronic infectious Daniel (DA) strain, the role of plasmacytoid dendritic cells (pDCs) is controversial. We herein found that TMEV binds to conventional DCs but not to pDCs. A glycomics analysis showed that the sialylated N-glycan fractions were lower in pDCs than in conventional DCs, indicating that pDCs are not susceptible to TMEV infection due to the low levels of sialic acid. TMEV capsid proteins contain an integrin recognition motif, and dot blot assays showed that the integrin proteins bind to TMEV and that the viral binding was reduced in the desialylated αX ß2 . αX ß2 protein suppressed TMEV replication in vivo, and TMEV co-localized with integrin αM at the cell membrane and TLR 3 in the cytoplasm, suggesting that αM serves as the viral attachment and entry. These results show that the chronic encephalomyelitis virus utilizes sialylated integrins as cell surface receptors, leading to cellular tropism to evade pDC activation.
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Encefalomielite , Integrinas , Camundongos , Animais , Receptores de Superfície Celular , Células Dendríticas , TropismoRESUMO
Cognitive scientists believe that adaptable intelligent agents like humans perform spatial reasoning tasks by learned causal mental simulation. The problem of learning these simulations is called predictive world modeling. We present the first framework for a learning open-vocabulary predictive world model (OV-PWM) from sensor observations. The model is implemented through a hierarchical variational autoencoder (HVAE) capable of predicting diverse and accurate fully observed environments from accumulated partial observations. We show that the OV-PWM can model high-dimensional embedding maps of latent compositional embeddings representing sets of overlapping semantics inferable by sufficient similarity inference. The OV-PWM simplifies the prior two-stage closed-set PWM approach to the single-stage end-to-end learning method. CARLA simulator experiments show that the OV-PWM can learn compact latent representations and generate diverse and accurate worlds with fine details like road markings, achieving 69 mIoU over six query semantics on an urban evaluation sequence. We propose the OV-PWM as a versatile continual learning paradigm for providing spatio-semantic memory and learned internal simulation capabilities to future general-purpose mobile robots.
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Transformer-based models have gained popularity in the field of natural language processing (NLP) and are extensively utilized in computer vision tasks and multi-modal models such as GPT4. This paper presents a novel method to enhance the explainability of transformer-based image classification models. Our method aims to improve trust in classification results and empower users to gain a deeper understanding of the model for downstream tasks by providing visualizations of class-specific maps. We introduce two modules: the "Relationship Weighted Out" and the "Cut" modules. The "Relationship Weighted Out" module focuses on extracting class-specific information from intermediate layers, enabling us to highlight relevant features. Additionally, the "Cut" module performs fine-grained feature decomposition, taking into account factors such as position, texture, and color. By integrating these modules, we generate dense class-specific visual explainability maps. We validate our method with extensive qualitative and quantitative experiments on the ImageNet dataset. Furthermore, we conduct a large number of experiments on the LRN dataset, which is specifically designed for automatic driving danger alerts, to evaluate the explainability of our method in scenarios with complex backgrounds. The results demonstrate a significant improvement over previous methods. Moreover, we conduct ablation experiments to validate the effectiveness of each module. Through these experiments, we are able to confirm the respective contributions of each module, thus solidifying the overall effectiveness of our proposed approach.
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BACKGROUND: Radiomics is a method for extracting a large amount of information from images and used to predict treatment outcomes, side effects and diagnosis. In this study, we developed and validated a radiomic model of [18F]FDG-PET/CT for predicting progression-free survival (PFS) of definitive chemoradiotherapy (dCRT) for patients with esophageal cancer. MATERIAL AND METHODS: Patients with stage II - III esophageal cancer who underwent [18F]FDG-PET/CT within 45 days before dCRT between 2005 and 2017 were included. Patients were randomly assigned to a training set (85 patients) and a validation set (45 patients). Radiomic parameters inside the area of standard uptake value ≥ 3 were calculated. The open-source software 3D slicer and Pyradiomics were used for segmentation and calculating radiomic parameters, respectively. Eight hundred sixty radiomic parameters and general information were investigated.In the training set, a radiomic model for PFS was made from the LASSO Cox regression model and Rad-score was calculated. In the validation set, the model was applied to Kaplan-Meier curves. The median value of Rad-score in the training set was used as a cutoff value in the validation set. JMP was used for statistical analysis. RStudio was used for the LASSO Cox regression model. p < 0.05 was defined as significant. RESULTS: The median follow-up periods were 21.9 months for all patients and 63.4 months for survivors. The 5-year PFS rate was 24.0%. In the training set, the LASSO Cox regression model selects 6 parameters and made a model. The low Rad-score group had significantly better PFS than that the high Rad-score group (p = 0.019). In the validation set, the low Rad-score group had significantly better PFS than that the high Rad-score group (p = 0.040). CONCLUSIONS: The [18F]FDG-PET/CT radiomic model could predict PFS for patients with esophageal cancer who received dCRT.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/terapia , Fluordesoxiglucose F18 , Intervalo Livre de Progressão , Prognóstico , QuimiorradioterapiaRESUMO
Weather variation in the distribution of image data can cause a decline in the performance of existing visual algorithms during evaluation. Adding additional samples of target domain to training data or using pre-trained image restoration methods such as de-hazing, de-raining, and de-snowing, to improve the quality of input images are two promising solutions. In this work, we propose Multiple Weather Translation GAN (MWTG), a CycleGAN-based, dual-purpose framework that simultaneously learns weather generation and its removal from image data. MWTG consists of four GANs constrained using cycle consistency that carry out domain translation tasks between hazy, rainy, snowy, and clear weather, using an asymmetric approach. To increase network capacity, we employ a spatial feature transform (SFT) layer to fuse the features extracted from the weather layer, which contains high-level domain information from the previous generators. Further, we collect an unpaired, real-world driving dataset recorded under various weather conditions called Realistic Driving Scenes under Bad Weather (RDSBW). We qualitatively and quantitatively evaluate MWTG using the RDSBW and the variation of Cityscapes that synthesize weather effects, eg., FoggyCityscape. Our experimental results suggest that MWTG can generate realistic weather in clear images and also accurately remove noise from weather images. Furthermore, the SOTA pedestrian detector ASCP is shown to achieve an impressive gain in detection precision after image restoration using the proposed MWTG method.
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In the field of intelligent vehicle technology, there is a high dependence on images captured under challenging conditions to develop robust perception algorithms. However, acquiring these images can be both time-consuming and dangerous. To address this issue, unpaired image-to-image translation models offer a solution by synthesizing samples of the desired domain, thus eliminating the reliance on ground truth supervision. However, the current methods predominantly focus on single projections rather than multiple solutions, not to mention controlling the direction of generation, which creates a scope for enhancement. In this study, we propose a generative adversarial network (GAN)-based model, which incorporates both a style encoder and a content encoder, specifically designed to extract relevant information from an image. Further, we employ a decoder to reconstruct an image using these encoded features, while ensuring that the generated output remains within a permissible range by applying a self-regression module to constrain the style latent space. By modifying the hyperparameters, we can generate controllable outputs with specific style codes. We evaluate the performance of our model by generating snow scenes on the Cityscapes and the EuroCity Persons datasets. The results reveal the effectiveness of our proposed methodology, thereby reinforcing the benefits of our approach in the ongoing evolution of intelligent vehicle technology.
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LiDAR point clouds are significantly impacted by snow in driving scenarios, introducing scattered noise points and phantom objects, thereby compromising the perception capabilities of autonomous driving systems. Current effective methods for removing snow from point clouds largely rely on outlier filters, which mechanically eliminate isolated points. This research proposes a novel translation model for LiDAR point clouds, the 'L-DIG' (LiDAR depth images GAN), built upon refined generative adversarial networks (GANs). This model not only has the capacity to reduce snow noise from point clouds, but it also can artificially synthesize snow points onto clear data. The model is trained using depth image representations of point clouds derived from unpaired datasets, complemented by customized loss functions for depth images to ensure scale and structure consistencies. To amplify the efficacy of snow capture, particularly in the region surrounding the ego vehicle, we have developed a pixel-attention discriminator that operates without downsampling convolutional layers. Concurrently, the other discriminator equipped with two-step downsampling convolutional layers has been engineered to effectively handle snow clusters. This dual-discriminator approach ensures robust and comprehensive performance in tackling diverse snow conditions. The proposed model displays a superior ability to capture snow and object features within LiDAR point clouds. A 3D clustering algorithm is employed to adaptively evaluate different levels of snow conditions, including scattered snowfall and snow swirls. Experimental findings demonstrate an evident de-snowing effect, and the ability to synthesize snow effects.
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BACKGROUND: Chronic rhinosinusitis is classified into eosinophilic chronic rhinosinusitis (ECRS) and non-eosinophilic chronic rhinosinusitis (NECRS). ECRS is a refractory allergic disease involving a variety of immune and epithelial cells. S100A8 is a damage-associated molecular pattern that is closely related to allergic inflammation. However, the pathological implications of S100A8 in ECRS have not been clarified. METHODS: We evaluated the role of S100A8 in the pathogenesis of ECRS. Gene expression profiles of nasal polyps obtained from patients with ECRS or NECRS were evaluated using RNA sequencing. RESULTS: S100A8 was identified as a significantly upregulated gene in nasal polyps associated with ECRS. Immunohistochemistry consistently revealed intense S100A8 staining in nasal polyps from patients with ECRS. Human nasal epithelial cells expressed the receptor for advanced glycation end products and Toll-like receptor 4. Recombinant S100A8 protein induced interleukin-1ß secretion in human nasal epithelial cells. CONCLUSIONS: Our data demonstrate that S100A8 results in production of interleukin-1ß in the nasal epithelium, which may be involved in the pathogenesis of ECRS.
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Calgranulina A , Interleucina-1beta , Pólipos Nasais , Rinite , Sinusite , Humanos , Calgranulina A/genética , Calgranulina A/metabolismo , Doença Crônica , Citocinas/metabolismo , Eosinófilos , Células Epiteliais , Interleucina-1beta/metabolismoRESUMO
Background: In the treatment of vertebral bone metastases, estimating patient prognosis is important to select the optimal treatment strategy. The purpose of this study was to identify prognostic factors for vertebral bone metastases treated with palliative radiotherapy and to establish a nomogram for predicting patient survival. Materials and methods: We analyzed patients who underwent palliative radiotherapy for vertebral bone metastasis between January 2010 and December 2020 at a single institution. Exclusion criteria were as follows: (1) primary bone malignancy, (2) stereotactic body radiotherapy, (3) concurrent radiotherapy to sites other than the vertebral bone, (4) radiotherapy to other sites within 12 weeks before or after the current radiotherapy, and (5) lack of more than half of blood test data before radiotherapy. Results: A total of 487 patients met the inclusion criteria. Clinical and hematologic data were collected from the patient record system. Patients were divided into training and test groups in a 7:3 ratio. Multivariate Cox regression analysis in the training cohort revealed six significant factors, including a history of chemotherapy, primary site (breast cancer, prostate cancer, or hematologic malignancy), use of analgesics, neutrophil-lymphocyte ratio, serum albumin, and lactate dehydrogenase. A prognostic nomogram was developed and validated in the test cohort. The area under the curve (AUC) values in predicting survival at 6, 24, and 60 months were 0.83, 0.88, and 0.88 in the training cohort and 0.85, 0.81, and 0.79 in the test cohort, respectively. Conclusions: This nomogram may help to select the treatment strategy for vertebral bone metastases.
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BACKGROUND: In clinical practice, the effect of durvalumab and radiation pneumonitis (RP) on survival after intensity-modulated radiotherapy (IMRT) is not fully understood. The purpose of this retrospective study was to investigate factors related to distant metastasis-free survival (DMFS), progression-free survival (PFS) and overall survival (OS) after IMRT for locally advanced non-small cell lung cancer (LA-NSCLC). METHODS: All patients who were treated with conventional fractionated IMRT for LA-NSCLC between April 2016 and March 2021 were eligible. Time-to-event data were assessed by using the Kaplan-Meier estimator, and the Cox proportional hazards model was used for prognostic factor analyses. Factors that emerged after the start of IMRT, such as durvalumab administration or the development of RP, were analysed as time-dependent covariates. RESULTS: A total of 68 consecutive patients treated with conventional fractionated IMRT for LA-NSCLC were analysed. Sixty-six patients completed radiotherapy, 50 patients received concurrent chemotherapy, and 36 patients received adjuvant durvalumab. During the median follow-up period of 14.3 months, 23 patients died, and tumour progression occurred in 37 patients, including 28 patients with distant metastases. The 1-year DMFS rate, PFS rate and OS rate were 59.9%, 48.7% and 84.2%, respectively. Grade 2 RP occurred in 16 patients, grade 3 in 6 patients and grade 5 in 1 patient. The 1-year cumulative incidences of grade 2 or higher RP and grade 3 or higher RP were 33.8% and 10.3%, respectively. The results of multivariate analyses showed that durvalumab had a significantly lower hazard ratio (HR) for DMFS, PFS and OS (HR 0.31, p < 0.01; HR 0.33, p < 0.01 and HR 0.32, p = 0.02), respectively. Grade 2 or higher RP showed significance for DMFS and a nonsignificant trend for OS (HR 2.28, p = 0.04 and HR 2.12, p = 0.13), respectively, whereas a higher percentage of lung volume receiving 20 Gy or higher was significant for PFS (HR 2.25, p = 0.01). CONCLUSIONS: In clinical practice, durvalumab administration following IMRT with concomitant chemotherapy showed a significant survival benefit. Reducing the risk of grade 2 or higher RP would also be beneficial.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Anticorpos Monoclonais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Quimiorradioterapia/efeitos adversos , Intervalo Livre de Doença , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Intervalo Livre de Progressão , Estudos RetrospectivosRESUMO
BACKGROUND: Palliative radiotherapy for gastric cancer bleeding has been reported to be a safe and effective treatment, but predictive factors for achievement of hemostasis and overall survival have not been established. METHODS: In this retrospective study, 120 courses of palliative radiotherapy for gastric cancer bleeding in 117 patients in 4 institutes in Japan were reviewed with approval of the ethical committee in each institute. The rate of achieving hemostasis was evaluated by 50% or more reduction of red blood cell transfusion before and after the start of radiotherapy, elevation of blood hemoglobin concentration in a period of 4 weeks from the start of radiotherapy or improvement of subjective or objective clinical symptoms in a period of 4 weeks from the start of radiotherapy. Predictive factors for overall survival and achieving hemostasis were investigated with the Cox hazards model. RESULTS: The median overall survival period was 3.7 months. Multivariate analysis showed that absence of metastatic disease, higher biological effective dose, higher serum albumin level, lower blood urea nitrogen level and lower neutrophil-to-lymphocyte ratio (NLR) were associated with longer overall survival. Elevation of hemoglobin concentration in a period of 4 weeks from the start of radiotherapy (mean concentration: 8.2 g/dL vs. 8.9 g/dL, p = 0.006) and decrease in the amount of red cell transfusion from a 4-week period before to a 4-week period after the start of radiotherapy (mean amount: 716 mL vs. 230 mL, p < 0.0001) were observed. The overall rate of achievement of hemostasis was 59.6%. In multivariate analysis, higher biological effective dose was associated with achievement of hemostasis. Grade 2 or higher acute adverse effects related to radiotherapy were observed in 17.5% of cases in 120 treatment courses. Six cases (5.0%) had grade 3 or 4 adverse effects including gastric penetration in 1 patient and anorexia requiring total parental nutrition in 3 patients. No grade 5 adverse effects were observed. CONCLUSIONS: Palliative radiotherapy for gastric cancer bleeding seems to be an effective and safe treatment strategy. Higher treatment dose was associated with longer overall survival and a hemostatic effect. Some hematological parameters may predict overall survival, and they would be helpful for deciding the treatment strategy.
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Neoplasias Gástricas , Hemorragia Gastrointestinal/complicações , Hemorragia Gastrointestinal/radioterapia , Hemoglobinas , Humanos , Cuidados Paliativos , Estudos Retrospectivos , Neoplasias Gástricas/complicações , Neoplasias Gástricas/radioterapiaRESUMO
PURPOSE: To evaluate the benefit of concurrent chemotherapy with radiotherapy (RT) for esophageal cancer in Asian patients aged ≥ 80 years using the Surveillance, Epidemiology, and End Results (SEER) database. MATERIALS AND METHODS: Among more than 7000 patients with squamous cell carcinoma or adenocarcinoma who were treated by RT without surgery for esophageal cancer in the SEER database, 2047 patients aged ≥ 80 years were analyzed. Patients who received chemoradiotherapy (CRT group) and patients who received RT alone (RT alone group) were matched with a propensity score. RESULTS: The median observation period for survivors was 57 months. The 3-year and 5-year overall survival rates in all patients were 15.2% and 8.5%, respectively. The 3-year and 5-year cause-specific survival rates in all patients were 20.8% and 14.5%, respectively. After propensity score matching, the overall survival rate in the CRT group was significantly higher than that in the RT alone group (5-year overall survival rates: 11.9% and 3.2%, respectively, p < 0.001). In 108 Asian or Pacific Islander patients, there was no significant difference (5-year overall survival rates: 13.5% and 0%, respectively, p = 0.291), although the overall survival rate in the CRT group was significantly higher than that in the RT alone group in any other race. CONCLUSIONS: It is controversial whether CRT is beneficial for Asian or Pacific Islander patients aged 80 years or older with esophageal cancer based on Analysis of data in SEER database.
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Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/métodos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , HumanosRESUMO
PURPOSE: The purpose of the present study was to evaluate patterns of recurrence after salvage chemoradiotherapy (SCRT) for postoperative loco-regional recurrent esophageal cancer. METHODS: We reviewed records for 114 patients with postoperative loco-regional recurrent esophageal cancer treated by platinum-based chemoradiotherapy between 2000 and 2020, and we evaluated the patterns of failure in patients who had recurrence again or who had been observed for 2 years or more after SCRT at the last observation date. RESULTS: One hundred and three patients were enrolled in this study. The median observation period for survivors was 60 months. Fifty-three patients died of esophageal cancer and nine patients died of other diseases. The 5-year overall survival rate, cause-specific survival rate and disease-control rate were 43.7%, 45.3% and 37.0%, respectively. Sixty-five patients had failure after SCRT. In those patients, 26 patients had only distant organ or non-regional lymph node metastases, 26 patients had only loco-regional failure, and 13 patients had both. Of those 65 patients, 64 patients showed failure within 42 months after SCRT. Of 39 patients with loco-regional failure, failure in the irradiated field was observed in 28 patients. Of those 28 patients, 27 patients showed failure within 24 months and the other patient showed failure at 26.5 months. CONCLUSIONS: The patterns of failure after SCRT for patients with postoperative loco-regional recurrent esophageal cancer were shown. The patterns of failure suggest that follow-up for at least 4 years after SCRT should be performed for those patients.
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Neoplasias Esofágicas , Recidiva Local de Neoplasia , Quimiorradioterapia/efeitos adversos , Neoplasias Esofágicas/radioterapia , Humanos , Japão/epidemiologia , Recidiva Local de Neoplasia/patologia , Terapia de SalvaçãoRESUMO
OBJECTIVE: Aging of populations has been rapidly increasing worldwide. The aim of this study was to identify prognostic factors of overall survival (OS) and progression-free survival (PFS) in patients aged 80 years or older who had esophageal cancer and received radiotherapy. METHODS: Patients aged 80 years or older who received radiotherapy between 2004 and 2015 were retrospectively reviewed. Pretreatment age, gender, performance status, Charlson comorbidity index score, tumor location, histology, clinical stage, results of blood tests and treatment methods were obtained to determine prognostic factors of OS and PFS. Survival curves were drawn using the Kaplan-Meier method and prognostic factors were analyzed using Cox's hazards model. RESULTS: Ninety-two patients were included. Thirty-five patients were treated with chemo-radiotherapy. The median follow-up period was 19.0 months. The 3-year OS and PFS rates were 44.7% and 28.4%, respectively. In multivariate analysis, clinical stage (hazard ratio [HR] 2.28, 95% confidence interval [CI] 1.40-3.73, p = 0.001) and the geriatric nutritional risk index (GNRI, HR 0.95, 95% CI 0.92-0.97, p < 0.001) were significant prognostic factors of OS. Clinical stage (HR 2.06, 95% CI 1.34-3.18, p = 0.001), tumor location (HR 2.04, 95% CI 1.39-3.01, p < 0.001) and GNRI (HR 0.96, 95% CI 0.94-0.99, p = 0.003) were significant prognostic factors of PFS. CONCLUSION: Clinical stage and GNRI were significant prognostic factors of OS and PFS. Tumor location was a significant prognostic factor of PFS. These prognostic factors might be useful for decision-making for elderly patients with esophageal cancer.
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Quimiorradioterapia , Neoplasias Esofágicas , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/radioterapia , Humanos , Prognóstico , Modelos de Riscos Proporcionais , Estudos RetrospectivosRESUMO
Immune responses against certain viruses are accompanied by auto-antibody production although the origin of these infection-associated auto-antibodies is unclear. Here, we report that murine γ-herpesvirus 68 (MHV68)-induced auto-antibodies are derived from polyreactive B cells in the germinal center (GC) through the activity of short-lived plasmablasts. The analysis of recombinant antibodies from MHV68-infected mice revealed that about 40% of IgG+ GC B cells were self-reactive, with about half of them being polyreactive. On the other hand, virion-reactive clones accounted for only a minor proportion of IgG+ GC B cells, half of which also reacted with self-antigens. The self-reactivity of most polyreactive clones was dependent on somatic hypermutation (SHM), but this was dispensable for the reactivity of virus mono-specific clones. Furthermore, both virus-mono-specific and polyreactive clones were selected to differentiate to B220lo CD138+ plasma cells (PCs). However, the representation of GC-derived polyreactive clones was reduced and that of virus-mono-specific clones was markedly increased in terminally differentiated PCs as compared to transient plasmablasts. Collectively, our findings demonstrate that, during acute MHV68 infection, self-reactive B cells are generated through SHM and selected for further differentiation to short-lived plasmablasts but not terminally differentiated PCs.
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Linfócitos B/imunologia , Centro Germinativo/imunologia , Infecções por Herpesviridae/imunologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
BACKGROUND AND AIMS: The great diversity of floral characteristics among animal-pollinated plants is commonly understood to be the result of coevolutionary interactions between plants and pollinators. Floral antagonists, such as nectar thieves, also have the potential to exert an influence upon the selection of floral characteristics, but adaptation against floral antagonists has attracted comparatively little attention. We found that the corollas of hornet-pollinated Codonopsis lanceolata (Campanulaceae) and the tepals of bee-pollinated Fritillaria koidzumiana (Liliaceae) are slippery to nectar-thieving ants living in the plant's habitat; because the flowers of both species have exposed nectaries, slippery perianths may function as a defence against nectar-thieving ants. METHODS: We conducted a behavioural experiment and observed perianth surface microstructure by scanning electron microscopy to investigate the mechanism of slipperiness. Field experiments were conducted to test whether slippery perianths prevent floral entry by ants, and whether ant presence inside flowers affects pollination. KEY RESULTS: Scanning electron microscopy observations indicated that the slippery surfaces were coated with epicuticular wax crystals. The perianths lost their slipperiness when wiped with hexane. Artificial bridging of the slippery surfaces using non-slippery materials allowed ants to enter flowers more frequently. Experimental introduction of live ants to the Codonopsis flowers evicted hornet pollinators and shortened the duration of pollinator visits. However, no statistical differences were found in the fruit or seed sets of flowers with and without ants. CONCLUSIONS: Slippery perianths, most probably based on epicuticular wax crystals, prevent floral entry by ants that negatively affect pollinator behaviour. Experimental evidence of floral defence based on slippery surfaces is rare, but such a mode of defence may be widespread amongst flowering plants.
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Formigas , Magnoliopsida , Animais , Abelhas , Flores , Néctar de Plantas , PolinizaçãoRESUMO
BACKGROUND: It is still controversial whether intensity-modulated radiotherapy has an obvious advantage over conventional radiotherapy. The purposes of this study were to evaluate prognostic factors in pre-treatment characteristics for nasopharyngeal carcinoma and to compare treatment outcomes in patients who received intensity-modulated radiotherapy and patients who received two-dimensional radiotherapy or three-dimensional radiotherapy. METHODS: We reviewed patients with nasopharyngeal carcinoma who received chemoradiotherapy in our hospital during the period from 2000 to 2017, and we excluded patients who had a history of surgery for nasopharyngeal carcinoma and those who had distant metastases before treatment. A total of 72 patients who were treated by radiotherapy with concurrent chemotherapy were enrolled. All of the patients were irradiated with a total dose of 58-70 Gy. Overall survival, locoregional control and progression-free survival rates were compared in the groups treated by intensity-modulated radiotherapy and two-dimensional/three-dimensional radiotherapy. Propensity score matching was performed to homogenize the two groups. RESULTS: The median follow-up period was 62.5 months. After propensity score matching, in patients treated with intensity-modulated radiotherapy, the 5-year rate of overall survival, locoregional control and progression-free survival were 73.5, 95.2 and 72.7%, respectively. In patients treated with two-dimensional/three-dimensional radiotherapy, the 5-year rate of overall survival, locoregional control and progression-free survival were 69.1, 67.7 and 51.8%, respectively. There was a significant difference between the groups only in locoregional control. Late toxicities of grade 2 or higher were occurred in 38.5 and 24.2% of the patients treated by two-dimensional/three-dimensional radiotherapy and intensity-modulated radiotherapy, respectively. CONCLUSIONS: Our results suggested that intensity-modulated radiotherapy is more effective than two-dimensional/three-dimensional radiotherapy in patients with nasopharyngeal carcinoma, especially in locoregional control.
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Carcinoma , Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Carcinoma/radioterapia , Quimiorradioterapia , Humanos , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Pontuação de Propensão , Estudos RetrospectivosRESUMO
Skilled interception behavior often relies on accurate predictions of external objects because of a large delay in our sensorimotor systems. To deal with the sensorimotor delay, the brain predicts future states of the target based on the current state available, but it is still debated whether internal representations acquired from prior experience are used as well. Here we estimated the predictive manner by analyzing the response behavior of a pursuer to a sudden directional change of the evasive target, providing strong evidence that prediction of target motion by the pursuer was incompatible with a linear extrapolation based solely on the current state of the target. Moreover, using neural network models, we validated that nonlinear extrapolation as estimated was computationally feasible and useful even against unknown opponents. These results support the use of internal representations in predicting target motion, suggesting the usefulness and versatility of predicting external object motion through internal representations.
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Percepção de Movimento , Encéfalo , Movimento (Física) , Redes Neurais de ComputaçãoRESUMO
BACKGROUND: Eosinophilic chronic rhinosinusitis (ECRS) is a subtype of chronic rhinosinusitis. Clinical markers for ECRS disease activity and treatment strategies have not been sufficiently established. Although semaphorins are originally identified as neuronal guidance factors, it is becoming clear that they play key roles in immune regulation and inflammatory diseases. OBJECTIVE: We sought to investigate the pathological functions and therapeutic potential of semaphorin 4D (SEMA4D) in ECRS. METHODS: Serum soluble SEMA4D levels in patients with paranasal sinus diseases were measured by ELISA. The expression of SEMA4D in blood cells and nasal polyp tissues was assessed by flow cytometry and immunohistochemistry, respectively. Generation of soluble SEMA4D was evaluated in matrix metalloproteinase-treated eosinophils. Endothelial cells were stimulated with recombinant SEMA4D, followed by eosinophil transendothelial migration assays. Allergic chronic rhinosinusitis was induced in mice using Aspergillus protease with ovalbumin. The efficacy of treatment with anti-SEMA4D antibody was evaluated histologically and by nasal lavage fluid analysis. RESULTS: Serum soluble SEMA4D levels were elevated in patients with ECRS and positively correlated with disease severity. Tissue-infiltrated eosinophils in nasal polyps from patients with ECRS stained strongly with anti-SEMA4D antibody. Cell surface expression of SEMA4D on eosinophils from patients with ECRS was reduced, which was due to matrix metalloproteinase-9-mediated cleavage of membrane SEMA4D. Soluble SEMA4D induced eosinophil transendothelial migration. Treatment with anti-SEMA4D antibody ameliorated eosinophilic infiltration in sinus tissues and nasal lavage fluid in the ECRS animal model. CONCLUSIONS: Eosinophil-derived SEMA4D aggravates ECRS. Levels of serum SEMA4D reflect disease severity, and anti-SEMA4D antibody has therapeutic potential as a treatment for ECRS.
Assuntos
Antígenos CD/metabolismo , Eosinofilia/metabolismo , Rinite/metabolismo , Semaforinas/metabolismo , Sinusite/metabolismo , Adulto , Animais , Antígenos CD/imunologia , Antígenos CD/farmacologia , Doença Crônica , Eosinofilia/imunologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Eosinófilos/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Proteínas Recombinantes/farmacologia , Rinite/imunologia , Semaforinas/imunologia , Semaforinas/farmacologia , Sinusite/imunologia , Migração Transendotelial e Transepitelial/efeitos dos fármacosRESUMO
BACKGROUND: Presence of unperfused regions containing cells under hypoxia and nutrient starvation; contributes to radioresistance in solid human tumors. We have previously reported that cultured cells; under nutrient starvation show resistance to ionizing radiation compare with cells under normal; condition, and that nutrient starvation increases ATM activity, which causes cellular resistance to; ionizing radiation (Murata et al., BBRC2018). For further investigation of molecular mechanisms; underlying radioresistance of cells under nutrient starvation, effects of nutrient starvation on activity; of DNA-PKcs have been investigated because both DNA-PKcs and ATM belong to the PIKK family; and are required for DNA DSBs repair. In addition to DNA-PKcs, effects of nutrient starvation on; activities of FoxO3a and its regulators Akt, MST1 and AMPK have been investigated because FoxO3a; mediates cellular responses to stress and is activated under nutrient starvation. METHODS: A human glioblastoma cell line, T98G was used to examine the effects of nutrient starvation on activities and expression of DNA-PKcs, Akt, MST1, FoxO3a, NDR1, and AMPK. To elucidate; signal transduction pathways for FoxO3a activation under nutrient starvation, we examined effects of; specific inhibitors or siRNA for DNA-PKcs or Akt on activities and expression of MST1, FoxO3, NDR1, andAMPK. RESULTS: Under nutrient starvation, phosphorylations of DNA-PKcs at Ser2056, Akt at Ser473, MST at Thr183, FoxO3a at Ser413, NDR1 at Ser281 and Thr282, and AMPK at Thr172 were increased, which suggests their activation. Nutrient starvation did not affect expression of DNA-PKcs, Akt, MST1, or NDR1, with decreased expression of FoxO3a and increased expression of AMPK. Inhibition; of DNA-PK suppressed phosphorylation of Akt under nutrient starvation. Inhibition of DNA-PK or; Akt suppressed phosphorylations of MST1, FoxO3a, and NDR1 under nutrient starvation, which; suggests DNA-PKcs and Akt activate MST1, FoxO3a, and NDR1. Inhibition of DNA-PK did not; suppress phosphorylation ofAMPK under nutrient starvation. CONCLUSION: Our data suggest that DN-PKcs is activated under nutrient starvation and activates AktMST1, FoxO3a, and NDR1.