Clinical implications of metastatic lymph node ratio in gastric cancer

<p>Abstract</p> <p>Background</p> <p>The 5-year survival rate in patients with gastric cancer is still poor, and lymph node metastasis is considered one of the most important prognostic factors. However, there are controversies in the classification of lymph node metastasis in gastric cancer. This study was carried out to investigate whether the metastatic lymph node ratio is a reliable classification of lymph node metastasis in gastric cancer in Chinese.</p> <p>Methods</p> <p>224 cases with gastric cancer with more than D1 dissection were retrospectively reviewed. The association between the total number of resected lymph nodes and the number of metastatic lymph nodes was determined. The prognostic value of the metastastic node ratio, defined as the ratio of the number of metastatic lymph nodes over the total number of resected lymph nodes, and the pN classification was assessed.</p> <p>Results</p> <p>The number of metastatic lymph node increased with the number of total resected lymph nodes. A Cox regression revealed that the metastatic node ratio, the number of metastatic nodes, histological type, and histological growth pattern independently influenced prognosis. The 5-year survival rates were 78%, 61%, 25%, 0% in cases with a metastastic node ratio of 0%, > 0% but < 40%, 40–80%, > 80%, respectively (<it>P </it>< 0.001), and were 78%, 62%, 38%, 0% in cases with gastric cancer histologically classified as pN0, pN1, pN2, pN3, respectively (<it>P </it>< 0.001).</p> <p>Conclusion</p> <p>The metastatic lymph node ratio is a simple and useful independent prognostic factor. It may obviate possible confounding factors that are related to stage migration, and should be considered as an important component in the lymph node category.</p

Stage-Specific Deletion of Olig2 Conveys Opposing Functions on Differentiation and Maturation of Oligodendrocytes

The temporal and spatial patterning involved in the specification, differentiation, and myelination by oligodendroglia is coordinated in part by the activation and repression of various transcriptional programs. Olig2 is a basic helix-loop-helix transcription factor necessary for oligodendroglial development and expressed continuously throughout the lineage. Despite evidence for the critical role of Olig2 in oligodendroglial specification and differentiation, the function for Olig2 during later stages of oligodendroglial development, namely, the transition into mature oligodendrocytes (OLs) and the formation of the myelin sheath, remains unclear. To address the possibility for a stage-specific role, we deleted Olig2 in oligodendrocyte precursor cells (OPCs) under the control of the CNPase-promoter or in immature OLs under the inducible proteolipid protein promoter. As expected, ablation of Olig2 in OPCs significantly inhibits differentiation, resulting in hypomyelination. However, deletion of the Olig2 gene in immature OLs significantly enhances the maturation process and accelerates the kinetics of myelination/remyelination. Underlying the stage-specific roles for Olig2 is the compensatory expression and function of Olig1, a transcription factor that promotes OL maturation and (re)myelination. Olig1 expression is significantly reduced upon Olig2 deletion in OPCs but is dramatically increased by nearly threefold when deleted in immature OLs. By enforcing expression of Olig1 into OPCs in a null Olig2 background, we demonstrate that overexpression of Olig1 is sufficient to rescue the differentiation phenotype and partially compensates for the Olig2 deletion in vitro. Our results suggest a stage-specific regulatory role for Olig2, mediated by Olig1 that conveys opposing functions on the differentiation and maturation of oligodendrocytes

Classifying the surrounding rock of tunnel face using machine learning

Accurately classifying the surrounding rock of tunnel face is essential. In this paper, we propose a machine learning-based automatic classification and dynamic prediction method of the surrounding rocks of tunnel face using the data monitored by a computerized rock drilling trolley based on the intelligent mechanized construction process for drilling and blasting tunnels. This method provides auxiliary support for the intelligent decision of dynamic support at the construction site. First, this method solves the imbalance in the classification of the surrounding rock samples by constructing the Synthetic Minority Oversampling Technique (SMOTE) algorithm using 500 samples of drilling parameters covering different levels and lithologies of a tunnel. Second, it filters the importance of the characteristic samples based on the random forest method. Third, it uses the XGBoost algorithm to model the processed data and compare it with AdaBoost and BP neural network models. The results show that the XGBoost model achieves a higher accuracy of 87.5% when the sample size is small. Finally, we validate the application scenarios of the above algorithm/model regarding the key aspects of the tunnel construction process, such as surrounding rock identification, design interaction, construction supervision, and quality evaluation, which facilitates the upgrading of intelligent tunnel construction

The complete chloroplast genome of Primula odontocalyx, a heterostylous species

Primula odontocalyx (Franch.) Pax (1905) is a perennial herb of the genus Primula in Primulaceae with heterostyly and ornamental value. Here, the chloroplast genome of P. odontocalyx was sequenced, assembled, and annotated. The complete chloroplast genome was a closed-circular molecule of 151,738 bp in length, containing a large single-copy region (LSC) of 83,817 bp, a small single-copy region (SSC) of 17,529 bp, and two inverted repeat (IR) regions of 25,196 bp. A total of 115 unique genes were annotated in the whole cp genome, including 81 protein-coding genes, 4 rRNA genes, and 30 tRNA genes. Phylogenetic analysis confirmed the close relationship between P. odontocalyx and Primula moupinensis, and both species belong to Sect. Petiolares Pax

The complete chloroplast genome of Primula vialii (Primulaceae), an ornamental plant

Primula vialii Delavay ex Franch. (1905) is an alpine species with an ornamental value. In this study, we sequenced, assembled, and annotated the chloroplast genome of P. vialii. The results showed that it was a double-stranded, closed circular DNA with 154,897 bp in length, comprising a small single-copy (SSC) region of 17,766 bp, a large single-copy (LSC) region of 85,379 bp and a pair of inverted repeat (IR) regions of 25,876 bp. A total of 113 unique genes were annotated, including 79 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. The phylogenetic analysis revealed that P. vialii is closely related to Primula flaccida. The cp genomic data will be useful for systematics and evolutionary studies of Primula

Study on chip formation in grinding nickel-based single-crystal superalloy DD5

According to the significant anisotropy of nickel-based single-crystal superalloy, a three-dimensional single abrasive grinding model based on the Hill model was developed. In this work, the change in the actual grinding thickness (ag) of the abrasive is taken into account in establishing the model. In addition, a combination of theoretical research and experimental research is used. The surface morphology and chip morphology of DD5 were first studied. Then, the evolution of chip morphology and the change in grinding force were investigated. Finally, the influence of grinding speed (vs) on chip morphology and chip segmentation frequency (fc) was studied. The research shows that serrated chips can easily occur when machining DD5 within the range of grinding parameters. The grinding force increased steadily and was accompanied by inevitable periodic fluctuations corresponding to serrated chips. As the grinding speed increased, the abrasive could enter the cutting stage more quickly, and its critical chip thickness (acr) eventually decreased from 0.225 μm to 0.158 μm. The percentage of the cutting phase increased from 85% to 89.5%. However, the critical scratch thickness was not significantly influenced by the change in grinding speed. The grinding speed and thickness substantially influence the morphology and segmentation frequency of DD5 chips. Specifically, as the grinding speed continues to increase, the DD5 chip morphology changes from a densely stacked unit nodal shape with serrated subsections to a continuous type of serrated shape and finally develops into a strip-shaped chip. At different grinding speeds, the chip segmentation frequency of DD5 decreases with increasing grinding depth