[Development progress of stationary phase for supercritical fluid chromatography and related application in natural products].

Supercritical fluid chromatography (SFC) is an environment-friendly and efficient column chromatography technology that was developed to expand the application range of high performance liquid chromatography (HPLC) using a supercritical fluid as the mobile phase. A supercritical fluid has a temperature and pressure that are above the critical values as well as relatively dynamic characteristics that are between those of a gas and liquid. Supercritical fluids combine the advantages of high solubility and diffusion, as their diffusion and viscosity coefficients are equivalent to those of a gas, while maintaining a density that is comparable with that of a liquid. Owing to the remarkable compressibility of supercritical fluids, analyte retention in SFC is significantly influenced by the density of the mobile phase. Thus, the column temperature and back pressure are crucial variables that regulate analyte retention in SFC. Increasing the back pressure can increase the density and solubility of the mobile phase, leading to reductions in retention time. The column temperature can affect selectivity and retention, and the degree to which different analytes are affected by this property varies. On the one hand, increasing the temperature reduces the density of the mobile phase, thereby extending the retention time of the analytes; on the other hand, it can also increase the energy of molecules, leading to a shorter retention time of the analyte on the stationary phase. CO2, the most widely employed supercritical fluid to date, presents moderate critical conditions and, more importantly, is miscible with a variety of polar organic solvents, including small quantities of water. In comparison with the mobile phases used in normal-phase liquid chromatography (NPLC) and reversed-phase liquid chromatography (RPLC), the mobile phase for SFC has a polarity that can be extended over a wide range on account of its extensive miscibility. The compatibility of the mobile phase determines the diversity of the stationary phase. Nearly all stationary phases for HPLC, including the nonpolar stationary phases commonly used for RPLC and the polar stationary phases commonly used for NPLC, can be applied to SFC. Because all stationary phases can use the same mobile-phase composition, chromatographic columns with completely different polarities can be employed in SFC. The selectivity of SFC has been effectively expanded, and the technique can be used for the separation of diverse analytes ranging from lipid compounds to polar compounds such as flavonoids, saponins, and peptides. The choice of stationary phase has a great impact on the separation effect of analytes in SFC. As new stationary phases for HPLC are constantly investigated, specialized stationary phases for SFC have also been continuously developed. Researchers have discovered that polar stationary phases containing nitrogen heterocycles such as 2-EP and PIC are highly suitable for SFC because they can effectively manage the peak shape of alkaline compounds and provide good selectivity in separating acidic and neutral compounds.The development of various stationary phases has promoted the applications of SFC in numerous fields such as pharmaceuticals, food production, environmental protection, and natural products. In particular, natural products have specific active skeletons, multiple active groups, and excellent biological activity; hence, these materials can provide many new opportunities for the discovery of novel drugs. According to reports, compounds related to natural products account for 80% of all commercial drugs. However, natural products are among the most challenging compounds to separate because of their complex composition and low concentration of active ingredients. Thus, superior chromatographic methods are required to enable the qualitative and quantitative analysis of natural products. Thanks to technological improvements and a good theoretical framework, the benefits of SFC are gradually becoming more apparent, and its use in separating natural products is expanding. Indeed, in the past 50 years, SFC has developed into a widely used and efficient separation technology. This article provides a brief overview of the characteristics, advantages, and development process of SFC; reviews the available SFC stationary phases and their applications in natural products over the last decade; and discusses prospects on the future development of SFC.

Progress in Research on Antitumor Drugs and Dynamic Changes in Skeletal Muscles.

Objective: To review the research progress of reltionship between antitumor drugs and the dynamic changes of the skeletal muscles during treatment phase. Background: Sarcopenia is a common disease in patients with tumors, and it has been agreed that patients with tumors and sarcopenia experience more serious adverse reactions and have a shorter long-term survival after antitumor therapy than patients without sarcopenia. Antitumor drugs whilst beneficial for tumor regression, interferes and synergizes with cancer-induced muscle wasting/sarcopenia, induced myodemia or intramuscular fat and the two conditions often overlap making it difficult to drive conclusions. In recent years, increasing attention has been paid to the dynamic changes in skeletal muscles during antitumor drug therapy. Dynamic changes refer not only measurement skeletal muscle quantity at baseline level, but give more emphasis on the increasing or decreasing level during or end of the whole treatment course. Methods: We retrievaled published English-language original research articles via pubmed, those studies mainly focused on repeated measurements of skeletal muscle index using computed tomography (CT) in cancer patients who received antitumor drug treatment but not received interventions that produced muscle mass change (such as exercise and nutritional interventions). Conclusion: This article will summarize the research progress to date. Most of antineoplastic drug cause skeletal muscle loss during the treatment course, loss of L3 skeletal muscle index is always associated with poor clinical outcomes.

LINC00961 functions as an anti-oncogene in non-small cell lung carcinoma by regulation of miR-3127.

BACKGROUND: This study set out to explore the regulatory relationship between LINC00961/miR-3127 axis and non-small-cell lung carcinoma (NSCLC), so as to provide a new and effective molecular target for targeted therapy of NSCLC. METHODS: RNA-seq and miRNA-seq data of NSCLC and normal samples were obtained from The Cancer Genome Atlas (TCGA) database for analyzing LINC00961 and miR-3127 expression. Eighty-six pairs of clinical NSCLC tissues and adjacent normal tissues as well as NSCLC cell lines were obtained. Measurements of LINK00961 and miR-3127 levels were done using real-time-quantitative polymerase chain reaction (RT-qPCR). Furthermore, LINK00961 and miR-3127 in NSCLC cell were regulated respectively. The NSCLC cell proliferation, invasion and migration were determined with MTT assay, Transwell and wound healing assays, respectively. The levels of invasion- and apoptosis-related proteins were detected using western blots, and the connection of LINC00961 and miR-3127 was identified using dual luciferase reporter (DLR) assay. RESULTS: Differential analysis results of TCGA databases identified that LINC00961 was ubiquitously expressed at low levels in NSCLC, while miR-3127 was highly expressed. Similar expression trends of LINC00961 and miR-3127 were observed in clinical NSCLC samples and cell lines. Overexpression of LINC00961 and knockdown of miR-3127 significantly reduced NCI-H1299 cell migration, invasiveness, and multiplication, decreased MMP-2, MMP-9 and Bcl-2 protein levels, and increased E-cadherin, Bax and Caspase-3 protein levels. The DLR assay confirmed that miR-3127 can be targeted by LINC00961. CONCLUSION: LINC00961 functions as an anti-oncogene in NSCLC by modulating miR-3127.

Development of BRAF V600E Mutation in NRAS Q61L Mutated Rectal Cancer.

BRAF and NRAS are oncogenes in the RAS/RAF/MEK/MAP-kinase signaling pathway. Coexistent mutations of BRAF and NRAS in a single colorectal cancer patient have always been considered mutually exclusive or at least rare. The clinical outcome of these patients remains undetermined. Herein we report a 53-year-old man harboring an NRAS Q61L mutation in his primary rectal carcinoma, who presented with a concomitant mutation of BRAF V600E in his liver metastasis biopsy 55 months after the primary CRC surgical resection. Our findings suggest that a BRAF and NRAS developed co-mutation may lead to a distinct clinicopathological progression. BRAF-mutated CRCwill not benefit from anti-RAS targeted therapy.

Qualitative and quantitative analysis in quality control of traditional Chinese medicines.

Separation techniques with high efficiency and sensitive detection have been widely used for quality control of traditional Chinese medicines (TCMs). High-performance liquid chromatography, gas chromatography, and capillary electrophoresis are commonly used to separate various components in TCMs. Ultraviolet detection, fluorescence detection, evaporative light-scattering detection, mass spectrometry and nuclear magnetic resonance can be applied to separation techniques for qualitative and quantitative analysis of TCMs. The development of quality control for TCMs based on quantitative and qualitative analysis from 2000 to 2007 are reviewed; the fingerprint technique is also discussed due to its broad application in the quality control of TCMs. Prospects for further research based on our primary results are also discussed.