Zhuojie Li, Chenxi Wu, Xiang Ding, Wenzhe Li, and Lei Xue
Cell Division, Vol 15, Iss 1, Pp 1-11 (2020)
Cell death, Drosophila, Toll, JNK, ROS, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282, Cytology, and QH573-671
Abstract Background Apoptosis plays pivotal roles in organ development and tissue homeostasis, with its major function to remove unhealthy cells that may compromise the fitness of the organism. Toll signaling, with the ancient evolutionary origin, regulates embryonic dorsal–ventral patterning, axon targeting and degeneration, and innate immunity. Using Drosophila as a genetic model, we characterized the role of Toll signaling in apoptotic cell death. Results We found that gain of Toll signaling is able to trigger caspase-dependent cell death in development. In addition, JNK activity is required for Toll-induced cell death. Furthermore, ectopic Toll expression induces the activation of JNK pathway. Moreover, physiological activation of Toll signaling is sufficient to produce JNK-dependent cell death. Finally, Toll signaling activates JNK-mediated cell death through promoting ROS production. Conclusions As Toll pathway has been evolutionarily conserved from Drosophila to human, this study may shed light on the mechanism of mammalian Toll-like receptors (TLRs) signaling in apoptotic cell death.
Cell Death and Disease, Vol 10, Iss 12, Pp 1-12 (2019)
Cytology and QH573-671
Abstract Cell death plays a pivotal role in animal development and tissue homeostasis. Dysregulation of this process is associated with a wide variety of human diseases, including developmental and immunological disorders, neurodegenerative diseases and tumors. While the fundamental role of JNK pathway in cell death has been extensively studied, its down-stream regulators and the underlying mechanisms remain largely elusive. From a Drosophila genetic screen, we identified Snail (Sna), a Zinc-finger transcription factor, as a novel modulator of ectopic Egr-induced JNK-mediated cell death. In addition, sna is essential for the physiological function of JNK signaling in development. Our genetic epistasis data suggest that Sna acts downstream of JNK to promote cell death. Mechanistically, JNK signaling triggers dFoxO-dependent transcriptional activation of sna. Thus, our findings not only reveal a novel function and the underlying mechanism of Sna in modulating JNK-mediated cell death, but also provide a potential drug target and therapeutic strategies for JNK signaling-related diseases.
Sitong Wang, Fanwu Wu, Bin Ye, Shiping Zhang, Xingjun Wang, Qian Xu, Guowang Li, Menglong Zhang, Shuai Wang, Yongsen Jia, Chunhua Jiang, Xiaojin La, Hong Chang, Zixue Zhao, Peng Li, Ji-an Li, and Chenxi Wu
BioMed Research International, Vol 2020 (2020)
Xuefu Zhuyu Decoction (XFZYD), a Traditional Chinese Medicine (TCM) decoction mainly for treating blood stasis syndrome, has been widely investigated and applied in clinic and in laboratory. XFZYD contains 11 herbs and has been identified to promoting blood circulation to remove blood stasis for cardiovascular disease. Meanwhile, blood stasis is directly related to malignant tumor according to TCM basic theory. However, the effects of XFZYD on tumor metastasis and the underlying mechanisms are still largely unknown. Here, we employed well-established Drosophila cell migration and tumor invasion models to explore whether XFZYD has the anticancer activity on tumor metastasis in vivo. Our work has demonstrated that XFZYD could suppress cell migration and tumor invasion at the moderate concentrations. In addition, XFZYD altered the expression of MMP1, β-integrin, and E-cadherin to impede cell migration. Moreover, XFZYD inhibited ocular tumor invasion presumably by reducing the activity of Notch signaling. Together, these evidences reveal a positive role of XFZYD in suppressing cell migration and tumor metastasis, providing the potential drug targets and key clues for cancer clinical treatment strategies.
Xiong Xiong, Yenan Tu, Xianchuan Chen, Xiaoming Jiang, Huahong Shi, Chenxi Wu, and James J. Elser
Heliyon, Vol 5, Iss 12, Pp e03063- (2019)
Environmental chemistry, Environmental hazard, Environmental pollution, Environmental risk assessment, Environmental toxicology, Microplastics, Science (General), Q1-390, Social sciences (General), and H1-99
It is vital to understand processes of microplastic ingestion and egestion by aquatic organisms in order to evaluate the potential effects and impacts of microplastics in aquatic ecosystems. In this study, goldfish (Carassius auratus) was used to investigate ingestion and egestion of polyethylene (PE) microplastics and how these processes were affected by size, color, and shape of microplastics. Results showed that goldfish ingested white PE microplastics only in the presence of fish feed and that microplastics larger than 2 mm were rejected even after being ingested. However, in the presence of food, more green and black microplastics were ingested compared with red, blue, and white microplastics while significantly higher amounts of microplastic films were ingested compared with fragments and filaments. Microplastics ingested by goldfish were egested within 72 h. However, the egestion rate of filaments was the lowest among all tested microplastic shapes. The presence of food appeared to reduce film and filament residues in fish after 72 h. Results of this study imply that different features of microplastics result in different exposure risks for fish. Thus, the specific features of microplastics (e.g. their shape, color, and size) should be considered in future ecotoxicological studies.
direction of arrival (DOA), coprime array, sensor failure, matrix reconstruction, redundant sensors, Chemical technology, and TP1-1185
A coprime array of N sensors can achieve Ο(N2) degrees of freedom (DOFs) bypossessing a uniform linear array segment of size Ο(N2) in the difference coarray. However, thestructure of difference coarray is sensitive to sensor failures. Once the sensor fails, the impact offailure sensors on the coarray structure may decrease the DOFs and cause direction finding failure.Therefore, the direction of arrival (DOA) estimation of coprime arrays with sensor failures is asignificant but challenging topic for investigation. Driven by the need for remedial measures, anefficient detection strategy is developed to diagnose the coprime array. Furthermore, based on thedifference coarray, we divide the sensor failures into two scenarios. For redundant sensor failurescenarios, the structure of difference coarray remains unchanged, and the coarray MUSIC(CO-MUSIC) algorithm is applied for DOA estimation. For non-redundant sensor failure scenarios,the consecutive lags of the difference coarray will contain holes, which hinder the application ofCO-MUSIC. We employ Singular Value Thresholding (SVT) algorithm to fill the holes withcovariance matrix reconstruction. Specifically, the covariance matrix is reconstructed into a matrixwith zero elements, and the SVT algorithm is employed to perform matrix completion, therebyfilling the holes. Finally, we employ root-MUSIC
Cell Death Discovery, Vol 4, Iss 1, Pp 1-10 (2018)
Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282, Cytology, and QH573-671
Abstract Pontin (Pont), also known as Tip49, encodes a member of the AAA+ (ATPases Associated with Diverse Cellular Activities) superfamily and plays pivotal roles in cell proliferation and growth, yet its function in cell death has remained poorly understood. Here we performed a genetic screen for dominant modifiers of Eiger-induced JNK-dependent cell death in Drosophila, and identified Pont as a negative regulator of JNK-mediated cell death. In addition, loss of function of Pont is sufficient to induce cell death and activate the transcription of JNK target gene puc. Furthermore, the epistasis analysis indicates that Pont acts downstream of Hep. Finally, we found that Pont is also required for JNK-mediated thorax development and acts as a negative regulator of JNK phosphorylation. Together, our data suggest that pont encodes a negative component of Egr/JNK signaling pathway in Drosophila through negatively regulating JNK phosphorylation, which provides a novel role of ATPase in Egr-JNK signaling.
Yingjie Guo, Chenxi Wu, Maozu Guo, Quan Zou, Xiaoyan Liu, and Alon Keinan
Frontiers in Genetics, Vol 10 (2019)
genome-wide association studies, single nucleotide polymorphisms, quantitative traits, linear mixed model, sparse group lasso, Genetics, and QH426-470
Genome-Wide association studies (GWAS), based on testing one single nucleotide polymorphism (SNP) at a time, have revolutionized our understanding of the genetics of complex traits. In GWAS, there is a need to consider confounding effects such as due to population structure, and take groups of SNPs into account simultaneously due to the “polygenic” attribute of complex quantitative traits. In this paper, we propose a new approach SGL-LMM that puts together sparse group lasso (SGL) and linear mixed model (LMM) for multivariate associations of quantitative traits. LMM, as has been often used in GWAS, controls for confounders, while SGL maintains sparsity of the underlying multivariate regression model. SGL-LMM first sets a fixed zero effect to learn the parameters of random effects using LMM, and then estimates fixed effects using SGL regularization. We present efficient algorithms for hyperparameter tuning and feature selection using stability selection. While controlling for confounders and constraining for sparse solutions, SGL-LMM also provides a natural framework for incorporating prior biological information into the group structure underlying the model. Results based on both simulated and real data show SGL-LMM outperforms previous approaches in terms of power to detect associations and accuracy of quantitative trait prediction.
Xin Yi, Jing Gao, Chenxi Wu, Dingxi Bai, Yingchun Li, Ni Tang, and Xiaoyun Liu
International Journal of Nursing Sciences, Vol 5, Iss 2, Pp 157-161 (2018)
Nursing and RT1-120
Background: This study aimed to determine the prevalence and predictive factors of prolonged grief disorder (PGD) among those bereaved by the Wenchuan earthquake in Southwestern China seven years after the event. Methods: A cross-sectional survey based on census tracts was conducted on the bereaved earthquake survivors. Responses to the questionnaire regarding PGD and its potential associated factors were obtained either through face-to-face or telephone interview. PGD was screened by a validated Chinese version of the PGD questionnaire-13 (PG-13). Bivariate and multivariate regression analyses were used to determine the prevalence and associated risk factors of PGD. Results: A total of 1464 bereaved earthquake survivors, with a response rate of 97.6%, were included in the study. Of the 1464 respondents studied, 124 (8.47%) were diagnosed with PGD. Multivariate regression analysis demonstrated that PGD in the bereaved earthquake individuals was significantly associated with several factors, including age, economic burden, close kinship with the deceased, and living with the deceased before the loss. Wenchuan earthquake bereaved aged 41–60 years were more likely to develop PGD compared to those aged younger than 40 or older than 60 (OR = 2.075, 95%CI = 1.297–3.319). Those who had a close kinship with the deceased had a higher tendency to develop PGD (OR = 5.144, 95%CI = 2.716–9.740). The odds of PGD among the earthquake bereaved with economic burdens were higher relative to those who did not experience an economic burden (OR = 8.123, 95%CI = 2.657–24.831). Those who living with the deceased before loss also had a higher tendency to develop PGD (OR = 0.179, 95%CI = 0.053–0.602). Conclusions: This study revealed that a significantly high proportion (8.47%) of the Wenchuan earthquake-bereaved remain grieving seven years after the event. Those diagnosed with PGD should receive appropriate interventions from clinical psychologists. The risk factors identified in this study are crucial for the early screening and prevention of PGD in future nursing and psycho-clinical practices. Keywords: Earthquake, Prolonged grief disorder, Root cause analysis, Cross-sectional studies
This paper analyses the influence of the spatial association of different provinces on technological diffusion and economic growth, using panel data from 30 Chinese provinces from 2005 to 2016. The results show that firstly, there is a strong spatial correlation in economic growth between the provinces from Moranâ€™s I index and Gearyâ€™s C index. Secondly, the decomposition of the direct and indirect effects in the spatial Durbin model reveals that foreign direct investment is a crucial factor for sustained economic growth. Last but not least, technological diffusion, exhibited in wave-like characteristics in China.