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Cordycepin, extracted from the medicinal mushroom Cordyceps militaris, was shown to induce cancer cell apoptosis. Yet its anticancer function was limitedly evaluated, and the mechanism was not entirely elucidated. In this study, we demonstrated the effectiveness of cordycepin in inducing apoptosis in HeLa cells and investigated its apoptosis-inducing mechanism through label-free surface-enhanced Raman spectroscopy (SERS). SERS spectral changes revealed detailed molecular changes in both early and late stages of apoptosis. Importantly, SERS characteristic peaks at 805 and 1438 cm&minus ; 1, which were assigned to RNA, continued to decrease significantly from early to late apoptosis stages. It indicated that cordycepin induced HeLa cell apoptosis mainly through interfering with RNA production, potentially by restraining the translation of RNA encoding ribosomal proteins. Meanwhile, apoptotic cells and their apoptosis stage could be easily differentiated by SERS-based principal component analysis (PCA). Furthermore, the morphological changes of early and late-stage apoptotic cells were illustrated by differential interference contrast and fluorescence microscopic imaging. Therefore, the natural ingredient, cordycepin, could serve as a promising anticancer candidate. Our biological model of cell apoptosis in vitro, the non-invasive and rapid SERS technique, combined with PCA analysis, could be a powerful tool in the investigation of cell apoptosis mechanisms and anticancer drug screening.

The object of research is linguistic informativity of the macrostructure of language reference books. The research material is bilingual (Russian-Tatar and Russian-Chinese) dictionaries of various types of the end of the 20th – beginning of the 21st cc. The paper presents the classification including various features of the existing bilingual dictionaries. Bilingual linguography comprises various types of anguage reference books. Most of the language reference books analyzed in this paper are monoscopal, with one source language and one target language. One of the key notions of linguography, as well as the essential component of a language reference book, is the vocabulary. One has to admit that in the modern linguography there is still no distinct objective criterion for selecting words for a language reference book. When composing a vocabulary, subjective factors play a great role. When researching the Russian-foreign language reference books, we revealed a number of mistakes and drawbacks referring to the vocabulary: a) unjustified inclusion of units into the vocabulary, b) unjustified absence of units in the vocabulary, c) orthographic mistakes, d) incorrect use of illustrative material (pictures, photos, etc.). There is no single established opinion as to what information a learner's dictionary should include. It is important to remember that inclusion of specific information depends on the dictionary's addressee and purpose.