Elevated NOX4 promotes tumorigenesis and acquired EGFR-TKIs resistance via enhancing IL-8/PD-L1 signaling in NSCLC.

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been widely used for human non-small-cell lung cancer (NSCLC) treatment. However, acquired resistance to EGFR-TKIs is the major barrier of treatment success, and new resistance mechanism remains to be elucidated. In this study, we found that elevated NADPH oxidase 4 (NOX4) expression was associated with acquired EGFR-TKIs resistance. Gefitinib is the first-generation FDA-approved EGFR-TKI, and osimertinib is the third-generation FDA-approved EGFR-TKI. We demonstrated that NOX4 knockdown in the EGFR-TKI resistant cells enabled the cells to become sensitive to gefitinib and osimertinib treatment, while forced expression of NOX4 in the sensitive parental cells was sufficient to induce resistance to gefitinib and osimertinib in the cells. To elucidate the mechanism of NOX4 upregulation in increasing TKIs resistance, we found that knockdown of NOX4 significantly down-regulated the expression of transcription factor YY1. YY1 bound directly to the promoter region of IL-8 to transcriptionally activate IL-8 expression. Interestingly, knockdown of NOX4 and IL-8 decreased programmed death ligand 1 (PD-L1) expression, which provide new insight on TKIs resistance and immune escape. We found that patients with higher NOX4 and IL-8 expression levels showed a shorter survival time compared to those with lower NOX4 and IL-8 expression levels in response to the anti-PD-L1 therapy. Knockdown of NOX4, YY1 or IL-8 alone inhibited angiogenesis and tumor growth. Furthermore, the combination of NOX4 inhibitor GKT137831 and gefitinib had synergistic effect to inhibit cell proliferation and tumor growth and to increase cellular apoptosis. These findings demonstrated that NOX4 and YY1 were essential for mediating the acquired EGFR-TKIs resistance. IL-8 and PD-L1 are two downstream targets of NOX4 to regulate TKIs resistance and immunotherapy. These molecules may be used as potential new biomarkers and therapeutic targets for overcoming TKIs resistance in the future.

Perylene-based molecular device: multifunctional spintronic and spin caloritronic applications.

Carbon-based magnetic molecular junctions are promising candidates for nanoscale spintronic applications because they are atomically thin and possess high stability and peculiar magnetism. Herein, based on first-principles and non-equilibrium Green's function, we designed a carbon-based molecular spintronic device composed of carbon atomic chains, zigzag-edged graphene nanoribbon (ZGNR), and a perylene molecule. Our results show that the device exhibits integrated spintronic and spin caloritronic functionalities, such as the bias-voltage driven spin filtering effect, negative differential resistance effect and giant magnetoresistance, temperature-gradient driven spin Seebeck effect, thermal spin filtering effect, high thermal magnetoresistance, and thermal colossal giant magnetoresistance. Furthermore, considering the phonon vibration effect, the spin and charge thermoelectric figure of merits (ZTsp and ZTch) can be enhanced and the peak of ZTsp is much larger than that of ZTch, indicating the excellent thermospin performance. The asymmetrical contact configuration between the carbon atomic chain and perylene/ZGNR inhibits the phonon thermal conductivity significantly, leading to the optimal ZTsp and ZTch of 2.4 and 0.5 at 300 K, respectively. These results suggest multifunctional spintronic and spin caloritronic applications for the perylene-based molecular device.

Metallothionein 2A (MT2A) controls cell proliferation and liver metastasis by controlling the MST1/LATS2/YAP1 signaling pathway in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is one of the three major cancers in the world and is the cancer with the most liver metastasis. The present study aimed to investigate the role of metallothionein 2A (MT2A) in the modulation of CRC cell proliferation and liver metastasis, as well as its molecular mechanisms. METHODS: The expression profile of metallothionein 2A (MT2A) in colorectal cancer retrieved from TCGA, GEO and Oncomine database. The biological effect of MT2A overexpression was investigated mainly involving cell proliferation and migration in CRC cells as well as growth and metastasis in CRC animal models. To explore the specific mechanism of MT2A metastasis in CRC, transcriptome sequencing was used to compare the overall expression difference between the control group and the MT2A overexpression group. RESULTS: Metallothionein 2A (MT2A) was downregulated in the tumor tissues of patients with CRC compared to adjacent normal tissues and was related to the tumor M stage of patients. MT2A overexpression inhibited CRC cell proliferation and migration in cells, as well as growth and metastasis in CRC animal models. While knockdown of MT2A had the opposite effect in cells. Western blotting confirmed that MT2A overexpression promoted the phosphorylation of MST1, LAST2 and YAP1, thereby inhibiting the Hippo signaling pathway. Additionally, specific inhibitors of MST1/2 inhibited MT2A overexpression-mediated phosphorylation and relieved the inhibition of the Hippo signaling pathway, thus promoting cell proliferation. Immunohistochemistry in subcutaneous grafts and liver metastases further confirmed this result. CONCLUSIONS: Our results suggested that MT2A is involved in CRC growth and liver metastasis. Therefore, MT2A and MST1 may be potential therapeutic targets for patients with CRC, especially those with liver metastases.

Dietary inflammatory index, inflammation biomarkers and preeclampsia risk: a hospital-based case-control study.

This study evaluated the association between inflammatory diets as measured by the Dietary Inflammatory index (DII), inflammation biomarkers and the development of preeclampsia among the Chinese population. We followed the reporting guidelines of the Strengthening the Reporting of Observational Studies in Epidemiology statement for observational studies. A total of 466 preeclampsia cases aged over 18 years were recruited between March 2016 and June 2019, and 466 healthy controls were 1:1 ratio matched by age (±3 years), week of gestation (±1 week) and gestational diabetes mellitus. The energy-adjusted DII (E-DII) was computed based on dietary intake assessed using a seventy-nine item semiquantitative FFQ. Inflammatory biomarkers were analysed by ELISA kits. The mean E-DII scores were -0·65 ± 1·58 for cases and -1·19 ± 1·47 for controls (P value < 0·001). E-DII scores positively correlated with interferon-γ (r s = 0·194, P value = 0·001) and IL-4 (r s = 0·135, P value = 0·021). After multivariable adjustment, E-DII scores were positively related to preeclampsia risk (Ptrend < 0·001). The highest tertile of E-DII was 2·18 times the lowest tertiles (95 % CI = 1·52, 3·13). The odds of preeclampsia increased by 30 % (95 % CI = 18 %, 43 %, P value < 0·001) for each E-DII score increase. The preeclampsia risk was positively associated with IL-2 (OR = 1·07, 95 % CI = 1·03, 1·11), IL-4 (OR = 1·26, 95 % CI = 1·03, 1·54) and transforming growth factor beta (TGF-ß) (OR = 1·17, 95 % CI = 1·06, 1·29). Therefore, proinflammatory diets, corresponding to higher IL-2, IL-4 and TGF-ß levels, were associated with increased preeclampsia risk.

Dietary and serum vitamin D and preeclampsia risk in Chinese pregnant women: a matched case-control study.

The effect of vitamin D (VD) on the risk of preeclampsia (PE) is uncertain. Few of previous studies focused on the relationship between dietary VD intake and PE risk. Therefore, we conducted this 1:1 matched case-control study to explore the association of dietary VD intake and serum VD concentrations with PE risk in Chinese pregnant women. A total of 440 pairs of participants were recruited during March 2016 to June 2019. Dietary information was obtained using a seventy-eight-item semi-quantitative FFQ. Serum concentrations of 25(OH)D2 and 25(OH)D3 were measured by liquid chromatography-tandem MS. Multivariate conditional logistic regression was used to estimate OR and 95 % CI. Restricted cubic splines (RCS) were plotted to evaluate the dose-response relationship of dietary VD intake and serum VD concentrations with PE risk. Compared with the lowest quartile, the OR of the highest quartile were 0·45 (95 % CI 0·29, 0·71, Ptrend = 0·001) for VD dietary intake and 0·26 (95 % CI 0·11, 0·60, Ptrend = 0·003) for serum levels after adjusting for confounders. In addition, the RCS analysis suggested a reverse J-shaped relationship between dietary VD intake and PE risk (P-nonlinearity = 0·02). A similar association was also found between serum concentrations of total 25(OH)D and PE risk (P-nonlinearity = 0·02). In conclusion, this study provides evidence that higher dietary intake and serum levels of VD are associated with the lower risk of PE in Chinese pregnant women.

LyP-1-fMWNTs enhanced targeted delivery of MBD1siRNA to pancreatic cancer cells.

Functionalized multi-walled carbon nanotubes have been extensively gained popularity in pancreatic cancer gene therapy. LyP-1, a peptide, has been proved to specifically bind pancreatic cancer cells. The potential therapeutic effect of LyP-1-conjugated functionalized multi-walled carbon nanotubes in treating pancreatic cancer is still unknown. In this study, LyP-1-conjugated functionalized multi-walled carbon nanotubes were successfully synthesized, characterized and showed satisfactory size distribution and zeta potential. Compared with functionalized multi-walled carbon nanotubes, cellular uptake of LyP-1-functionalized multi-walled carbon nanotubes was shown to be increased. Compound of LyP-1-functionalized multi-walled carbon nanotubes and MBD1siRNA showed superior gene transfection efficiency. Moreover, LyP-1-fMWNTs/MBD1siRNA complex could significantly decrease the viability and proliferation and promoted apoptosis of pancreatic cancer cells in vitro. Further xenograft assays revealed that the tumour burden in the nude mice injected with LyP-1-functionalized multi-walled carbon nanotubes/MBD1siRNA was significantly relieved. The study demonstrated that LyP-1-functionalized multi-walled carbon nanotubes/MBD1siRNA could be a promising candidate for tumour active targeting therapy in pancreatic cancer.

Exosomal miR-223 derived from natural killer cells inhibits hepatic stellate cell activation by suppressing autophagy.

BACKGROUND: Activation of hepatic stellate cells (HSCs) is a prominent driver of liver fibrosis. We previously demonstrated that exosomes derived from natural killer (NK) cells (NK-Exo) attenuated TGF-ß1-induced HSC activation. Herein, this study was designed to investigate the mechanism underlying the action of NK-Exo. METHODS: NK-Exo was isolated from NK-92MI cells and then administered into TGF-ß1-treated LX-2 (human HSC line) cells. MiR-223 expression in NK-Exo was downregulated by transfecting NK-92MI cells with miR-223 inhibitor followed by exosome isolation. The HSC activation was evaluated by determining cell proliferation using CCK-8 assay and measuring the protein levels of α-SMA and CoL1A1 using western blot in LX-2 cells. The expression of miR-223 was detected by qRT-PCR. The interaction between miR-223 and ATG7 was analyzed by a dual-luciferase activity assay. The autophagy was evaluated by measuring the autophagy-related proteins using western blot. RESULTS: miR-223 was highly expressed in NK-Exo and inhibition of miR-223 expression in NK-Exo abrogated the inhibitory effect of NK-Exo on TGF-ß-induced HSC activation. ATG7 was confirmed as a direct target of miR-223. Furthermore, treatment with the autophagy activator rapamycin and ATG7 overexpression in LX-2 cells abolished the HSC activation-suppressive effect of NK-Exo. CONCLUSION: NK-Exo attenuated TGF-ß-induced HSC activation by transferring miR-223 that inhibited autophagy via targeting ATG7.

Huge field enhancement and high transmittance enabled by terahertz bow-tie aperture arrays: a simulation study.

Sub-wavelength aperture arrays featuring small gaps have an extraordinary significance in enhancing the interactions of terahertz (THz) waves with matters. But it is difficult to obtain large light-substance interaction enhancement and high optical response signal detection capabilities at the same time. Here, we propose a simple terahertz bow-tie aperture arrays structure with a large electric field enhancement factor and high transmittance at the same time. The field enhancement factor can reach a high value of 1.9×104 and the transmission coefficient of around 0.8 (the corresponding normalized-to-area transmittance is about 14.3) at 0.04 µm feature gap simultaneously. The systematic simulation results show that the designed structure can enhance the intensity of electromagnetic hotspot by continuously reducing the feature gap size without affecting the intensity of the transmittance. We also visually displayed the significant advantages of extremely strong electromagnetic hot spots in local terahertz refractive index detection, which provides a potential platform and simple strategy for enhanced THz spectral detection.

[Regulation of Chrysophanol-mediated TLR4/NF-κB Pathway on Renal Injury and Immune Response in IgA Nephropathy Rats].

OBJECTIVE: To investigate the regulatory effect and its mechanism of chrysophanol (CP) on renal injury and immune response in immunoglobin A (IgA) nephropathy rats. METHODS: IgA nephropathy rat model was established by the method of lipopolysaccharide + bovine serum protein + carbon tetrachloride. Then the rats were randomly divided into 5 groups: control group, IgA group, IgA+low, medium and high dose of CP groups(2.5, 5 and 10 mg/kg for each group respectively). IgA+CP groups were intraperitoneally injected with different doses of chrysophanol once a day for 4 weeks, and the control group and IgA group were given isovolumetric saline. Urine protein content, serum creatinine and urea nitrogen were detected at 24 h after the administration of drugs. Kidney histopathological damage and apoptosis were measured by HE and TUNEL staining. The expression levels of Caspase-3 and Caspase-9 were detected by RT-PCR and Western blot; The contents of malondialdehyde (MDA), superoxide dismutase (SOD) and (glutathione peroxidase, Gpx) were detected by enzyme-linked immunosorbent assay (ELISA). The expression of interleukin-1ß, -6 (IL-1ß, IL-6) and tumor necrosis factor (TNF-α) in serum and kidney tissue were measured by ELISA and Western blot, respectively. The mRNA and protein expression levels of toll-like receptro 4 (TLR4), nuclear factor-κB P65 (NF-κB P65) were also detected by RT-PCR and Western blot, and vascular cell adherin molecule (VCAM-1) protein level was deteted by Western blot. RESULTS: In IgA nephropathy rats, the administration of CP reduced proteinuria, serum creatinine and urea nitrogen in a dose-dependent manner (P < 0.01). It also improved the pathological damage of kidney tissue, reduced the apoptosis rate (P < 0.01), and decreased the mRNA and protein expression levels of apoptosis-related proteins Caspase-3 and Caspase-9 (P < 0.01). CP inhibited MDA production while increased the activities of antioxidant enzymes Gpx and SOD (P < 0.01), and decreased the levels of serum and protein expression of IL-1ß, IL-6 and TNF-α (P < 0.01), as well as the expression levels of TLR4, NF-κB P65 and VCAM-1 (P < 0.01). CONCLUSION: Chrysophanol could play a protective role in IgA nephropathy rats, and its mechanism may be related to alleviating kidney injury and regulating immune response.

Demographic expansion and genetic load of the halophyte model plant Eutrema salsugineum.

The halophyte model plant Eutrema salsugineum (Brassicaceae) disjunctly occurs in temperate to subarctic Asia and North America. This vast, yet extremely discontinuous distribution constitutes an ideal system to examine long-distance dispersal and the ensuing accumulation of deleterious mutations as expected in expanding populations of selfing plants. In this study, we resequenced individuals from 23 populations across the range of E. salsugineum. Our population genomic data indicate that E. salsugineum migrated "out of the Altai region" at least three times to colonize northern China, northeast Russia and western China. It then expanded its distribution into North America independently from northeast Russia and northern China, respectively. The species colonized northern China around 33.7 thousand years ago (kya) and underwent a considerable expansion in range size approximately 7-8 kya. The western China lineage is likely a hybrid derivative of the northern China and Altai lineages, originating approximately 25-30 kya. Deleterious alleles accumulated in a stepwise manner from (a) Altai to northern China and North America and (b) Altai to northeast Russia and North America. In summary, E. salsugineum dispersed from Asia to North America and deleterious mutations accumulated in a stepwise manner during the expansion of the species' distribution.

Effects of SDF-1/CXCR4 on the Repair of Traumatic Brain Injury in Rats by Mediating Bone Marrow Derived Mesenchymal Stem Cells.

Our study aims to investigate the effects of the SDF-1/CXCR4 axis on the repair of traumatic brain injury (TBI) in rats by mediating bone marrow derived from mesenchymal stem cells (BMSCs). Healthy male SD rats were collected, their tibiofibulars were removed, cultured, and BMSCs were collected. The expression of cell-surface molecular proteins was examined using flow cytometry. The mRNA and protein expression of CXCR4 in cells were tested using qRT-PCR and western blotting analysis. An electronic brain injury instrument was utilized to build TBI rat models and each rat was assigned into the experiment, positive control and control groups (10 rats in each group). The morris water maze was used to calculate the escape latency and number of times rats in each group crossed the platform. Neurological severity scores (NSS) was calculated to evaluate the recovery of neurological functioning. The distribution of neuronal nuclear antigens was detected using double-labeling immunohistochemistry. The morphological changes in the hippocampal neuronal and the number of BrdU-positive cells were observed through Nissl's staining and high magnification. The mRNA and protein expressions of CXCR4 were gradually increased as SDF-1 concentration increased. NGF and BDNF positive cells were expressed in each group. The distribution of neuronal nuclear antigens in the experiment group was elevated compared to the control and positive control groups. Among the three groups, the experimental group had the shortest escape latency and the highest number platform crossings. The difference in NSS among the three groups was significant. The experimental group had better cell morphology and a higher number of BrdU-positive cells than the other groups. The present study demonstrates that transplanting BMSCs with SDF-1-induced CXCR4 expression can promote the repair of TBI. This is expected to become a new treatment regimen for TBI.

Photoinduced charge transfer by one and two-photon absorptions: physical mechanisms and applications.

We review photoinduced charge transfer in organic solar cells without and with an external electric field and then we introduce the visualization methods of the transition density, charge difference density and transition density matrix for the analysis of the photoinduced charge transfer in a neutral system and a charged system excited by one-photon and two-photon absorption. This review will not only promote a deeper understanding of the available theories and methods of PICT, but also lead to further developments in this field.

High mobility group box 1 promotes sorafenib resistance in HepG2 cells and in vivo.

BACKGROUND: Primary liver cancer is a lethal malignancy with a high mortality worldwide. Currently, sorafenib is the most effective molecular-targeted drug against hepatocellular carcinoma (HCC). However, the sorafenib resistance rate is high. The molecular mechanism of this resistance has not been fully elucidated. High mobility group box 1 (HMGB1) is a multifaceted protein that plays a key role in the proliferation, apoptosis, metastasis and angiogenesis of HCC cells. In addition, HMGB1 has been suggested to contribute to chemotherapy resistance in tumours, including lung cancer, osteosarcoma, neuroblastoma, leukaemia, and colorectal cancer. This study investigated the association between HMGB1 and sorafenib resistance in HCC. METHODS: HepG2 cells with HMGB1 knockdown or overexpression were generated. The efficacy of sorafenib in these cells was tested using flow cytometry and a cell counting assay. The subcellular localization of HMGB1 in HepG2 cells following sorafenib treatment was measured by western blotting and confocal microscopy. A murine subcutaneous HCC model was generated to examine the association between HMGB1 and the sensitivity of sorafenib treatment. RESULTS: The HMGB1 knockdown cells exhibited a significantly higher apoptotic level and lower cell viability than the normal HMGB1 expressing cells following the sorafenib treatment. In addition, the cell viability observed in the HMGB1 overexpressing cells was higher than that observed in the control cells following the sorafenib intervention. Sorafenib had a better tumour inhibition effect in the HMGB1 knockdown group in vivo. The amount of mitochondrial HMGB1 decreased, while the amount of cytosolic HMGB1 increased following the exposure to sorafenib. Altogether, HMGB1 translocated from the mitochondria to the cytoplasm outside the mitochondria following the exposure of HepG2 cells to sorafenib. CONCLUSIONS: A novel potential role of HMGB1 in the regulation of sorafenib therapy resistance in HCC was observed. The knockdown of HMGB1 restores sensitivity to sorafenib and enhances HepG2 cell death, while HMGB1 overexpression blunts these effects. The translocation of HMGB1 from the mitochondria to the cytosol following sorafenib treatment provides new insight into sorafenib resistance in HCC.

Comparative pharmacokinetic profile of cyclosporine (CsA) with a decapeptide and a linear analogue.

The synthesis and in vivo pharmacokinetic profile of an analogue of cyclosporine is disclosed. An acyclic congener was also profiled in in vitro assays to compare cell permeability. The compounds possess similar calculated and measured molecular descriptors however have different behaviors in an RRCK assay to assess cell permeability.

Arsenic trioxide intravenous infusion combined with transcatheter arterial chemoembolization for the treatment of hepatocellular carcinoma with pulmonary metastasis: Long-term outcome analysis.

OBJECTIVE: To evaluate the safety, clinical efficacy, and long-term outcome of arsenic trioxide (As2 O3 ) intravenous infusion for pulmonary metastases in patients with HCC. MATERIALS AND METHODS: Sixty consecutive patients who were diagnosed with advanced hepatocellular carcinoma (HCC) with pulmonary metastasis were randomized 1:1 into the treatment and control groups. Treatment group underwent transcatheter arterial chemoembolization (TACE) for the primary liver tumor and then underwent As2 O3 treatment, whereas control group underwent TACE alone. The treatment group underwent a continuous 5-h intravenous infusion of 10 mg/day As2 O3 . The course of As2 O3 treatment was initiated 3-5 days after TACE (to allow liver and gastrointestinal function to recover) and continued for 14 consecutive days. All patients in the treatment group underwent at least four treatment courses. Response to treatment was evaluated after four treatment courses. RESULT: In treatment group, two patients had a complete response (CR), six had a partial response (PR), 10 had stable disease (SD), and 12 had progressive disease. A clinically effective rate (CR + PR) was achieved in 26.7%, and the clinical benefit rate (CR + PR + SD) was 60%. In the control group, no patients had a CR or PR, five had SD, and 25 had progressive disease. The clinically effective rate was 0%, and the clinical benefit rate was 16.7%. The overall 1-year survival was 56.7% in treatment group and 36.7% in control group. The overall 2-year survival was 16.7% in treatment group and 3.3% in control group. CONCLUSION: Transcatheter arterial chemoembolization plus an intravenous infusion of As2 O3 effectively controlled pulmonary metastasis and prolonged overall survival in patients with HCC compared with TACE alone.

The atomistic origin of interface confinement and enhanced conversion efficiency in Si nanowire solar cells.

The photoelectric properties of Si nanowires (SiNWs) under interface confinement are investigated based on the atomic-bond-relaxation consideration and the detailed balance principle. An analytical model is developed to elucidate the interface confinement and power conversion efficiency (PCE). It is found that the band curvature and surface barrier height decrease with decreasing size. The interface recombination rate and PCE can be determined by the size, shell thickness and local interface conditions. Our theoretical results show evident improvement in the PCE of SiNWs under interface confinement compared to that of a bare nanowire, highlighting the feasibility of the epitaxial layer as a booster for highly efficient SiNW solar cells.

Germanicol induces selective growth inhibitory effects in human colon HCT-116 and HT29 cancer cells through induction of apoptosis, cell cycle arrest and inhibition of cell migration.

PURPOSE: The main aim of this research was to evaluate the anticancer and apoptotic effects of germanicol - a natural triterpene - in HCT-116 and HT29 human colon cancer cells and deciphering its mode of action by studying its effect on the cell cycle and cell migration. METHODS: Cell cytotoxicity was evaluated by MTT assay, while cell death was assessed by LDH assay. Fluorescence microscopy, using DAPI and acridine orange/ethidium bromide (AO-ETBR), was carried out to evaluate the effect of germanicol on cellular morphology and apoptosis induction. Apoptosis quantification was performed by Annexin V-FITC assay, while cell cycle analysis was performed by flow cytometry using propidium iodide (PI). RESULTS: The results revealed that germanicol showed selective, potent and dose-dependent cytotoxicity in HCT-116 and HT29 human colon cancer cells, while it showed lower cytotoxicity in normal colon cells (human colon fibroblast, CCD-18Co). LDH assay also showed that germanicol induced dose-dependent cell death in HCT-116 and HT29 cells. Fluorescence microscopy revealed that germanicol induced apoptosis via chromatin condensation and DNA damage in HCT-116 colon cancer cells. It also revealed that the percentage of cells with orange and red fluorescence increased when adding a germanicol dose, indicating apoptosis. Germanicol also inhibited cancer cell migration. CONCLUSION: The current findings reveal that germanicol exhibits selective antiproliferative activity against two human colon cancer cells. The normal cell line was less affected by the drug, as compared to the two cancer cell lines, indicating that germanicol will not target normal living cells. The antiproliferative effect was shown to be mediated through the induction of apoptosis and suppression of cell migration.

[DNA Barcoding of Mongolian Oxytropis Medicinal Materials].

Objective: To identify Oxytropis medicinal materials using ITS2 sequence. Methods: The second internal transcribed spacer( ITS2) of Oxytropis fetissovii, Oxytropis myriophylla and Oxytropis grandiflora medicinal material samples was amplified by PCR and sequenced. To expand scope of the research topic,ITS2 sequences of related species were downloaded from Gen Bank. Sequences assembly and consensus sequence generation were performed by ITS2 Database. The related data analysis and processing was performed using software MEGA 5. 10 and the NJ tree was constructed. The ITS2 secondary structure was predicted using ITS2 web server, and the differences of the ITS2 secondary structures of the samples were analyzed. Results: Oxytropis medicinal materials ITS2 sequence was shorter, with sequence length of 216 ~ 218 bp, which was in favor of DNA extraction, PCR amplification and sequencing. Genetic distances of Oxytropis myriophylla, Oxytropis fetissovii and Oxytropis grandiflora were much larger than the genetic distances of themselves. In the NJ tree, Oxytropis medicinal materials and counterfeits could be distinguished, and Oxytropis medicinal materials could be distinguished from Astragalus membranaceus. Conclusion: The DNA barcode based on ITS2 sequence is a powerful and efficient tool for identification of Oxytropis medicinal materials.

[DNA Barcoding of Mongolian Medicinal Plant Scutellaria scordifolia].

Objective: To authenticate Scutellaria scordifolia and its closely related species using ITS2 sequence. Methods: Total genomic DNA was isolated from Scutellaria scordifolia and its related species. Nuclear DNA ITS2 sequences were amplified and sequenced,and ITS2 sequences of the other species of plants were obtained in Gen Bank,The Kimura 2-parameter( K2P) distances were calculated. Identification analyses were performed using Neighbor-joining( NJ) and secondary structure of ITS2 sequence methods. Results: The genetic distances of ITS2 between Scutellaria scordifolia and its closely related species were 0. 014 ~ 0. 141,which were obviously higher than those in the intra-species of Scutellaria scordifolia. The NJ tree and secondary structure of ITS2 sequence can distinguish Scutellaria scordifolia and its closely related species. Conclusion: ITS2 sequence can effectively and accurately identify the Mongolian medicinal plant Scutellaria scordifolia and its closely relatives.