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Oral squamous cell carcinoma (OSCC) represents one of the most common head and neck cancer that with dire prognosis due partly to the lack of reliable prognostic biomarker. Here, we aimed to develop a CpG site-based prognostic signature through which we could accurately predict overall survival (OS) of patients with OSCC. We obtained OSCC-related DNA methylation and gene expression data sets from the public accessible Gene Expression Omnibus. Correlations between methylation level of CpG sites and OS of patients with OSCC were assessed by univariate Cox regression analysis followed by robust likelihood-based survival analysis on those CpG sites with permutation P < 0.05 for further screening the optimal CpG sites for OSCC OS prediction based on the risk score formula that composed of the methylation level of optimal CpG sites weighted by their regression coefficients. Besides, differential expression genes (DEGs) and differential methylation genes (DMGs) in OSCC samples compared with normal samples were obtained and shared genes were considered as vital genes in OSCC tumorgenesis and progression. As a result, two CpG sites including cg17892178 and cg17378966 that located in NID2 and IDO1, respectively, were identified as the optimal prognostic signatures for OSCC OS. In addition, 12 overlapping genes between DEGs and DMGs that closely associated with inflammation or blood and tissue development-related biological processes were obtained. In conclusions, this study should provide valuable signatures for OSCC diagnosis and treatment.

During mammalian oocyte growth, chromatin configuration transition from the nonsurrounded nucleolus (NSN) to surrounded nucleolus (SN) type plays a key role in the regulation of gene expression and acquisition of meiotic and developmental competence by the oocyte. Nonetheless, the mechanism underlying chromatin configuration maturation in oocytes is poorly understood. Here we show that nucleolar protein DCAF13 is an important component of the ribosomal RNA (rRNA)-processing complex and is essential for oocyte NSN-SN transition in mice. A conditional knockout of Dcaf13 in oocytes led to the arrest of oocyte development in the NSN configuration, follicular atresia, premature ovarian failure, and female sterility. The DCAF13 deficiency resulted in pre-rRNA accumulation in oocytes, whereas the total mRNA level was not altered. Further exploration showed that DCAF13 participated in the 18S rRNA processing in growing oocytes. The lack of 18S rRNA because of DCAF13 deletion caused a ribosome assembly disorder and then reduced global protein synthesis. DCAF13 interacted with a protein of the core box C/D ribonucleoprotein, fibrillarin, i.e., a factor of early pre-rRNA processing. When fibrillarin was knocked down in the oocytes from primary follicles, follicle development was inhibited as well, indicating that an rRNA processing defect in the oocyte indeed stunts chromatin configuration transition and follicle development. Taken together, these results elucidated the in vivo function of novel nucleolar protein DCAF13 in maintaining mammalian oogenesis.

Meiotic resumption‐coupled degradation of maternal transcripts occurs during oocyte maturation in the absence of mRNA transcription. The CCR4–NOT complex has been identified as the main eukaryotic mRNA deadenylase. In vivo functional and mechanistic information regarding its multiple subunits remains insufficient. Cnot6l , one of four genes encoding CCR4–NOT catalytic subunits, is preferentially expressed in mouse oocytes. Genetic deletion of Cnot6l impaired deadenylation and degradation of a subset of maternal mRNAs during oocyte maturation. Overtranslation of these undegraded mRNAs caused microtubule–chromosome organization defects, which led to activation of spindle assembly checkpoint and meiotic cell cycle arrest at prometaphase. Consequently, Cnot6l −/− female mice were severely subfertile. The function of CNOT6L in maturing oocytes is mediated by RNA‐binding protein ZFP36L2, not maternal‐to‐zygotic transition licensing factor BTG4, which interacts with catalytic subunits CNOT7 and CNOT8 of CCR4–NOT. Thus, recruitment of different adaptors by different catalytic subunits ensures stage‐specific degradation of maternal mRNAs by CCR4–NOT. This study provides the first direct genetic evidence that CCR4–NOT‐dependent and particularly CNOT6L‐dependent decay of selective maternal mRNAs is a prerequisite for meiotic maturation of oocytes.

In this paper, we present a leaf vein extracting algorithm frame which deals with contour and interior vein by employing different methods. The interior vein extraction method based on gray scale processing, mathematical morphology and processing in details is presented. We apply gray-scale morphology to process the image and extract the vein information. Through the analysis of the image information, processing in details is adopted to clear the information on the other tissues and insignificant veins. The extracted significant interior vein is overlaid with the leaf contour extracted through edge detection by pixel union operation. Experiment results show the effectiveness of the proposed method.

We have investigated the feedback control of the cooperative dynamics of two coupled electrochemical oscillators that is induced merely by external noise. The interacting electrochemical cells are modeled with parameter values at which no autonomous oscillations occur, and each unit is forced by its own source of random fluctuations. Application of delayed feedback to only one of two subsystems is shown to be able to change the coherence and time scales of noise-induced oscillations either in the given subsystem or globally. It can also induce or suppress stochastic resonance under the certain conditions.