MHR-Net: Multiple-Hypothesis Reconstruction of Non-Rigid Shapes from 2D Views

We propose MHR-Net, a novel method for recovering Non-Rigid Shapes from Motion (NRSfM). MHR-Net aims to find a set of reasonable reconstructions for a 2D view, and it also selects the most likely reconstruction from the set. To deal with the challenging unsupervised generation of non-rigid shapes, we develop a new Deterministic Basis and Stochastic Deformation scheme in MHR-Net. The non-rigid shape is first expressed as the sum of a coarse shape basis and a flexible shape deformation, then multiple hypotheses are generated with uncertainty modeling of the deformation part. MHR-Net is optimized with reprojection loss on the basis and the best hypothesis. Furthermore, we design a new Procrustean Residual Loss, which reduces the rigid rotations between similar shapes and further improves the performance. Experiments show that MHR-Net achieves state-of-the-art reconstruction accuracy on Human3.6M, SURREAL and 300-VW datasets.Comment: Accepted to ECCV 202

Brain-inspired Graph Spiking Neural Networks for Commonsense Knowledge Representation and Reasoning

How neural networks in the human brain represent commonsense knowledge, and complete related reasoning tasks is an important research topic in neuroscience, cognitive science, psychology, and artificial intelligence. Although the traditional artificial neural network using fixed-length vectors to represent symbols has gained good performance in some specific tasks, it is still a black box that lacks interpretability, far from how humans perceive the world. Inspired by the grandmother-cell hypothesis in neuroscience, this work investigates how population encoding and spiking timing-dependent plasticity (STDP) mechanisms can be integrated into the learning of spiking neural networks, and how a population of neurons can represent a symbol via guiding the completion of sequential firing between different neuron populations. The neuron populations of different communities together constitute the entire commonsense knowledge graph, forming a giant graph spiking neural network. Moreover, we introduced the Reward-modulated spiking timing-dependent plasticity (R-STDP) mechanism to simulate the biological reinforcement learning process and completed the related reasoning tasks accordingly, achieving comparable accuracy and faster convergence speed than the graph convolutional artificial neural networks. For the fields of neuroscience and cognitive science, the work in this paper provided the foundation of computational modeling for further exploration of the way the human brain represents commonsense knowledge. For the field of artificial intelligence, this paper indicated the exploration direction for realizing a more robust and interpretable neural network by constructing a commonsense knowledge representation and reasoning spiking neural networks with solid biological plausibility

Prognostic impact of H3K27me3 expression on locoregional progression after chemoradiotherapy in esophageal squamous cell carcinoma

<p>Abstract</p> <p>Background</p> <p>Trimethylation of lysine 27 on histone H3 (H3K27me3) by enhancer of zeste homolog 2 (EZH2) is an epigenetic mark that mediates gene silencing. EZH2 is overexpressed and correlates with poor prognosis in many cancers. However, the clinical implication of H3K27me3 in human malignancies has not been well established. We wished to ascertain whether a correlation exists between the expression of H3K27me3 and clinical outcome in a group of patients with esophageal squamous cell carcinoma (ESCC) treated with definitive chemoradiotherapy (CRT).</p> <p>Methods</p> <p>The method of immunohistochemistry (IHC) was utilized to examine the protein expression of H3K27me3 in 98 pretreatment biopsy specimens of ESCC and in 30 samples of normal esophageal mucosa. The clinical/prognostic significance of H3K27me3 expression was statistically analyzed.</p> <p>Results</p> <p>The expression frequency and expression levels of H3K27me3 were significantly higher in ESCCs than in normal tissues. There was a positive correlation between H3K27me3 expression and WHO grade (<it>P </it>= 0.016), tumor size (<it>P </it>= 0.019), T status (<it>P </it>= 0.024), locoregional progression (<it>P </it>= 0.009) and EZH2 expression (<it>P </it>= 0.036). High H3K27me3 expression was associated with poor locoregional progression-free survival (LPFS) (<it>P </it>= 0.010) in ESCC. Further analysis demonstrated that H3K27me3 could stratify patient outcome in T2-3 (<it>P </it>= 0.048), N0 (<it>P </it>= 0.005) and M0 (<it>P </it>= 0.018) stages as well as in CRT effective group (<it>P </it>= 0.022).</p> <p>Conclusions</p> <p>Our data suggests that H3K27me3 expression examined by IHC might be useful for stratifying LPFS for different subsets of ESCC patients treated with definitive CRT.</p

ApoG2 induces cell cycle arrest of nasopharyngeal carcinoma cells by suppressing the c-Myc signaling pathway

<p>Abstract</p> <p>Background</p> <p>apogossypolone (ApoG2) is a novel derivate of gossypol. We previously have reported that ApoG2 is a promising compound that kills nasopharyngeal carcinoma (NPC) cells by inhibiting the antiapoptotic function of Bcl-2 proteins. However, some researchers demonstrate that the antiproliferative effect of gossypol on breast cancer cells is mediated by induction of cell cycle arrest. So this study was aimed to investigate the effect of ApoG2 on cell cycle proliferation in NPC cells.</p> <p>Results</p> <p>We found that ApoG2 significantly suppressed the expression of c-Myc in NPC cells and induced arrest at the DNA synthesis (S) phase in a large percentage of NPC cells. Immunoblot analysis showed that expression of c-Myc protein was significantly downregulated by ApoG2 and that the expression of c-Myc's downstream molecules cyclin D1 and cyclin E were inhibited whereas p21 was induced. To further identify the cause-effect relationship between the suppression of c-Myc signaling pathway and induction of cell cycle arrest, the expression of c-Myc was interfered by siRNA. The results of cell cycle analysis showed that the downregulation of c-Myc signaling pathway by siRNA interference could cause a significant arrest of NPC cell at S phase of the cell cycle. In CNE-2 xenografts, ApoG2 significantly downregulated the expression of c-Myc and suppressed tumor growth <it>in vivo</it>.</p> <p>Conclusion</p> <p>Our findings indicated that ApoG2 could potently disturb the proliferation of NPC cells by suppressing c-Myc signaling pathway. This data suggested that the inhibitory effect of ApoG2 on NPC cell cycle proliferation might contribute to its use in anticancer therapy.</p

Learning Task-preferred Inference Routes for Gradient De-conflict in Multi-output DNNs

Multi-output deep neural networks(MONs) contain multiple task branches, and these tasks usually share partial network filters that lead to the entanglement of different task inference routes. Due to the inconsistent optimization objectives, the task gradients used for training MONs will interfere with each other on the shared routes, which will decrease the overall model performance. To address this issue, we propose a novel gradient de-conflict algorithm named DR-MGF(Dynamic Routes and Meta-weighted Gradient Fusion) in this work. Different from existing de-conflict methods, DR-MGF achieves gradient de-conflict in MONs by learning task-preferred inference routes. The proposed method is motivated by our experimental findings: the shared filters are not equally important to different tasks. By designing the learnable task-specific importance variables, DR-MGF evaluates the importance of filters for different tasks. Through making the dominances of tasks over filters be proportional to the task-specific importance of filters, DR-MGF can effectively reduce the inter-task interference. The task-specific importance variables ultimately determine task-preferred inference routes at the end of training iterations. Extensive experimental results on CIFAR, ImageNet, and NYUv2 illustrate that DR-MGF outperforms the existing de-conflict methods both in prediction accuracy and convergence speed of MONs. Furthermore, DR-MGF can be extended to general MONs without modifying the overall network structures.Comment: 15 page

Pluripotency-associated genes in human nasopharyngeal carcinoma CNE-2 cells are reactivated by a unique epigenetic sub-microenvironment.

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.BACKGROUND: There is increasing evidence that cancers contain their own stem-like cells, and particular attention has been paid to one subset of cancer-stem cells termed side population (SP). Stem cells under normal physical conditions are tightly controlled by their microenvironment, however, the regulatory role of the microenvironment surrounding cancer stem cells is not well characterized yet. In this study we found that the phenotype of SP can be "generated" by macrophage-like cells under conditioned culture. Furthermore the gene regulation pathway involved in cellular reprogramming process was investigated. METHODS: The selection and identification of SP in 50 CNE-2 single cell clones were performed by flow cytometry. The transwell assay and immunofluorescence staining were used to measure migration and cancer stem cell characters of non-SP single clone cells cultured with conditioned medium respectively. The subtraction suppression hybridization (SSH) technique and northern blotting analysis was applied to explore the pluripotency-associated genes under a unique epigenetic sub-microenvironment. RESULTS: Among 50 clones, only one did not possess SP subpopulation while others did. The non-SP cells induced by macrophage-like cells showed more aggressive characters, which increased cell migration compared with the control cells and showed some fraction of SP phenotype. These cells expressed distinguished level of pluripotency-associated genes such as ADP-ribosylation factor-like 6 interacting protein (ARMER), poly (rC) binding protein 1 (PCBP1) and pyruvate dehydrogenase E1-beta subunit (PDHB) when subjected to the environment. CONCLUSION: To our knowledge, this is the first study to demonstrate that non-SP single-clone cells can be induced to generate a SP phenotype when they are cultured with conditioned medium of macrophage-like cells, which is associated with the reactivation of pluripotency-associated genes.Peer Reviewe

Association between genetic polymorphisms of CYP2A13, CYP2A6 and risk of nasopharyngeal carcinoma in southern Chinese population

Abstract: Background: Cytochrome P450 2A13 (CYP2A13) and 2A6 (CYP2A6) are enzymes expressed in the human respiratory tract, exhibit high efficiency in the metabolic activation of tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). A C→T transition in the CYP2A13 gene causes Arg257Cys amino acid substitution and a deletion of the CYP2A6 gene named as CYP2A6 *4, both of them result in a significantly reduced activity toward NNK and other substrates. In this case-control study, we investigated the association between the CYP2A13 and CYP2A6 variants, smoking status and the risk of developing nasopharyngeal carcinoma (NPC) in the Cantonese population living in southern China. Materials and Methods: Genotypes of CYP2A13 and CYP2A6 genes were analyzed by using polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) assays and two-step PCR method. Results: Neither the CYP2A13 -3375T variants nor CYP2A6 *4 variants were associated with risk of NPC (OR = 0.84, 95% CI = 0.59-1.20, and OR = 0.83, 95% CI = 0.58-1.18, respectively) compared with their wild genotypes. Combination analysis showed that individuals with both CYP2A13 CT or TT variants and CYP2A6 *4 variants had no association with risk for NPC (OR = 0.71, 95% CI = 0.33-1.52) compared with those with both CYP2A13 CC and CYP2A6 *1/*1 genotypes. No association with the risk of NPC was observed in smokers with CYP2A13 C/T polymorphisms or smokers with CYP2A6 *4 variant polymorphisms (OR = 0.75, 95% CI = 0.43-1.32, and OR = 0.90, 95% CI = 0.27-1.70; respectively), including after stratification of smoking status. Furthermore, we did not observe association between the combination of two gene polymorphisms and smokers and risk of developing NPC, including the stratification of smoking. Discussions: Based on the results of this study, the effect of these two CYP2A13 and CYP2A6 enzymes may be not so important in developing of NPC as in other cancers, such as lung cancer. ). http://www.cancer-biology.org

Genetic polymorphisms of TLR3 are associated with Nasopharyngeal carcinoma risk in Cantonese population

<p>Abstract</p> <p>Background</p> <p>Nasopharyngeal carcinoma is endemic in Southern China, displays a strong relationship with genetic susceptibility and associates with Epstein-Barr virus infection. Toll-like receptor 3 (TLR3) plays an important role in the antivirus response. Therefore, we examined the association between <it>TLR3 </it>gene polymorphisms and NPC susceptibility.</p> <p>Methods</p> <p>We performed a case-control study of 434 NPC cases and 512 healthy controls matched on age, sex and residence. Both cases and controls are of Cantonese origin from Southern China. Genetic variants in <it>TLR3 </it>were determined by polymerase chain reaction (PCR)-based DNA direct sequencing and four SNPs were genotyped in all samples.</p> <p>Results</p> <p>Our results showed that allele C for SNP 829A/C increased NPC risk significantly ((p = 0.0068, OR = 1.49, 95%CI:1.10–2.00). When adjusted for age, gender and VCA-IgA antibody titers, the NPC risk was reduced significantly among individuals who carried the haplotype "ATCT" compared to those who carried the most common haplotype "ACCT" (p = 0.0054, OR = 0.028; 95% CI (0.002–0.341).</p> <p>Conclusion</p> <p>The <it>TLR3 </it>polymorphisms may be relevant to NPC susceptibility in the Cantonese population, although the reduction in NPC risk is modest and the biological mechanism of the observed association merits further investigation.</p

Rhodamine-triazine based probes for Cu²⁺ in aqueous media and living cells

The performance of a number of rhodamine-triazine derivatives（probe R1~R4) which utilize rhodamine as the fluorophore with cyanuric chloride as the molecular platform have been evaluated. Spectroscopic analysis revealed that differing structural substitution patterns of the probe resulted in different sensitivity and selectivity for specific metal ions. The probes R1 and R2 were fluorescent/colorimetric probes for Cu²⁺, whilst R3 and R4 were probes for Al³⁺, Cr³⁺ and Fe³⁺. The probe R2 exhibited superior recognition for Cu²⁺ in neutral aqueous medium, and the optical switching behavior of R2 for Cu²⁺ and S²⁻ could be used to construct a molecular logic gate. In addition, fluorescence imaging of probe R2 for Cu²⁺ in living cells was demonstrated