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81.
Multi-species compartment epidemic models, such as the multi-species susceptible–infectious–recovered (SIR) model, are extensions of the classic SIR models, which are used to explore the transient dynamics of pathogens that infect multiple hosts in a large population. In this article, we propose a dynamical Bayesian hierarchical SIR (HSIR) model, to capture the stochastic or random nature of an epidemic process in a multi-species SIR (with recovered becoming susceptible again) dynamical setting, under hidden mass balance constraints. We call this a Bayesian hierarchical multi-species SIR (MSIRB) model. Different from a classic multi-species SIR model (which we call MSIRC), our approach imposes mass balance on the underlying true counts rather than, improperly, on the noisy observations. Moreover, the MSIRB model can capture the discrete nature of, as well as uncertainties in, the epidemic process. 相似文献
82.
Qiuxia Wang Congcong Liu Lili Xu Fangzhou Zhuang Bo Guan Guangcan Lin Chengdong Peng 《Zeitschrift fur angewandte Ichthyologie》2020,36(4):542-544
Parameters of the length-weight relationship (LWR) were estimated for four fish species [Beaufortia szechuanensis (Fang, 1930), Claea dabryi (Sauvage, 1874), Percocypris pingi (Tchang, 1930), and Yunnanilus sichuanensis Ding, 1995] from the Yalong River. Samples were collected seasonally from June 2018 to July 2019, using various fishing gears [set nets (mesh: 1.5 × 2.0 cm), hook, drift gill nets (three mesh sizes: 1.0; 2.0; 3.0 cm) and electro fishing]. Two new maximum standard length were recorded for C. dabryi and P. pingi. 相似文献
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84.
Yi Shi Ronghan He Ze Zhuang Jianhua Ren Zhe Wang Yuangao Liu Jiajun Wu Shihai Jiang Kun Wang 《Journal of cellular biochemistry》2020,121(7):3479-3490
Osteosarcoma (OS) is the most common primary solid malignant bone tumor, and its metastasis is a prominent cause of high mortality in patients. In this study, a prognosis risk signature was constructed based on metastasis-associated genes. Four microarrays datasets with clinical information were downloaded from Gene Expression Omnibus, and 256 metastasis-associated genes were identified by limma package. Further, a protein-protein interaction network was constructed, and survival analysis was performed using data from the Therapeutically Applicable Research to Generate Effective Treatments data matrix, identifying 19 genes correlated with prognosis. Six genes were selected by the least absolute shrinkage and selection operator regression for multivariate cox analysis. Finally, a three-gene (MYC, CPE, and LY86) risk signature was constructed, and datasets GSE21257 and GSE16091 were used to validate the prediction efficiency of the signature. The survival times of low- and high-risk groups were significantly different in the training set and validation set. Additionally, gene set enrichment analysis revealed that the genes in the signature may affect the cell cycle, gap junctions, and interleukin-6 production. Therefore, the three-gene survival risk signature could potentially predict the prognosis of patients with OS. Further, proteins encoded by CPE and LY86 may provide novel insights into the prediction of OS prognosis and therapeutic targets. 相似文献
85.
Mei Du Yuan Zhuang Peng Tan Zongbu Yu Xiutian Zhang Aihua Wang 《Journal of cellular physiology》2020,235(2):944-956
This study investigated the role of microRNA-95 (miR-95) in gastric cancer (GC) and to elucidate the underlying mechanism. Initially, bioinformatic prediction was used to predict the differentially expressed genes and related miRNAs in GC. miR-95 and DUSP5 expression was altered in GC cell line (MGC803) to evaluate their respective effects on the epithelial–mesenchymal transition (EMT) process, cellular processes (cell proliferation, migration, invasion, cell cycle, and apoptosis), cancer stem cell (CSC) phenotype, as well as tumor growth ability. It was further predicted in bioinformatic prediction and verified in GC tissue and cell line experiments that miR-95 was highly expressed in GC. miR-95 negatively regulated DUSP5, which resulted in the MAPK pathway activation. Inhibited miR-95 or overexpressed DUSP5 was observed to inhibit the levels of CSC markers (CD133, CD44, ALDH1, and Lgr5), highlighting the inhibitory role in the CSC phenotype. More important, evidence was obtained demonstrating that miR-95 knockdown or DUSP5 upregulation exerted an inhibitory effect on the EMT process, cellular processes, and tumor growth. Together these results, miR-95 knockdown inhibited GC development via DUSP5-dependent MAPK pathway. 相似文献
86.
Zhen Yu Ming Chang Min Wu Guiqin Yang Shungui Zhou Li Zhuang 《Archives of microbiology》2013,195(12):815-822
A Gram-staining-negative, rod-shaped and motile with several polar flagellums bacterium, designated WM-3T, was isolated from a rice paddy soil in South China. Growth occurred with 0–3.0 % (w/v) NaCl (optimum 2.0 %), at pH 5.5–9.0 (optimum pH 7.0) and at 25–42 °C (optimum 30–37 °C) in liquid Reasoner’s 2A medium. Analysis of the 16S rRNA gene and gyrB gene sequences revealed that strain WM-3T was most closely related to the type strains of the species Pseudomonas linyingensis and Pseudomonas sagittaria. Its sequence similarities with P. linyingensis CGMCC 1.10701T and P. sagittaria JCM 18195T were 97.4 and 97.3 %, respectively, for 16S rRNA gene, and were 94.1 and 94.2 %, respectively, for gyrB gene. DNA–DNA hybridization between strain WM-3T and these two type strains showed relatedness of 35.6 and 30.9 %, respectively. G+C content of genomic DNA was 69.4 mol%. The whole-cell fatty acids mainly consisted of C16:0 (30.0 %), C16:1 ω6c and/or C16:1 ω7c (19.3 %) and C18:1 ω6c and/or C18:1 ω7c (16.3 %). The results of phenotypic, chemotaxonomic and genotypic analyses clearly indicated that strain WM-3T belongs to genus Pseudomonas but represents a novel species, for which the name Pseudomonas oryzae sp. nov. is proposed. The type strain is WM-3T (=KCTC 32247T =CGMCC 1.12417T). 相似文献
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Hiroyuki Hosokawa Phat Vinh Dip Maria Merkulova Anastasia Bakulina Zhenjie Zhuang Ashok Khatri Xiaoying Jian Shawn M. Keating Stephanie A. Bueler John L. Rubinstein Paul A. Randazzo Dennis A. Ausiello Gerhard Grüber Vladimir Marshansky 《The Journal of biological chemistry》2013,288(8):5896-5913
Previously, we reported an acidification-dependent interaction of the endosomal vacuolar H+-ATPase (V-ATPase) with cytohesin-2, a GDP/GTP exchange factor (GEF), suggesting that it functions as a pH-sensing receptor. Here, we have studied the molecular mechanism of signaling between the V-ATPase, cytohesin-2, and Arf GTP-binding proteins. We found that part of the N-terminal cytosolic tail of the V-ATPase a2-subunit (a2N), corresponding to its first 17 amino acids (a2N(1–17)), potently modulates the enzymatic GDP/GTP exchange activity of cytohesin-2. Moreover, this peptide strongly inhibits GEF activity via direct interaction with the Sec7 domain of cytohesin-2. The structure of a2N(1–17) and its amino acids Phe5, Met10, and Gln14 involved in interaction with Sec7 domain were determined by NMR spectroscopy analysis. In silico docking experiments revealed that part of the V-ATPase formed by its a2N(1–17) epitope competes with the switch 2 region of Arf1 and Arf6 for binding to the Sec7 domain of cytohesin-2. The amino acid sequence alignment and GEF activity studies also uncovered the conserved character of signaling between all four (a1–a4) a-subunit isoforms of mammalian V-ATPase and cytohesin-2. Moreover, the conserved character of this phenomenon was also confirmed in experiments showing binding of mammalian cytohesin-2 to the intact yeast V-ATPase holo-complex. Thus, here we have uncovered an evolutionarily conserved function of the V-ATPase as a novel cytohesin-signaling receptor. 相似文献
90.