ABSTRACT
italic>Dendrobium officinale Kimura et Migo is a rare Chinese herbal medicine, while Dendrobium crepidatum Lindl is a local medicine in Yunnan, both of which have the function of nourishing yin and stomach. To reveal the differences in chemical composition between the two species, ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS/MS) was used to analyze the chemical composition of stems and leaves of D. officinale and D. crepidatum. Principal component analysis (PCA) and partial least squares discriminant analysis (OPLS-DA) were used to determine the differences in metabolites between species and parts of Dendrobium. Fifty-eight chemical compounds were identified in the two species. Analysis indicated that the side ring of alkaloids connected with nitrogen was readily cleaved during analysis. The results of PCA analysis showed that the stems and leaves of D. officinale and D. crepidatum could be easily differentiated, and the chemical constituents of D. officinale and D. crepidatum were significantly different. OPLS-DA analysis showed that there were 16 metabolite differences between the stems and 22 differences in metabolites between the leaves of D. officinale and D. crepidatum. The main metabolite differences in components between the two Dendrobium species were dendrocrepidine B, dendrocrepidine C and dendrocrepine. There were 14 differences in metabolites between the stems and leaves of D. crepidatum. In conclusion, the chemical compositions of D. officinale and D. crepidatum are quite different; the small molecular compounds of D. officinale are mainly terpenoids and flavonoids, and the content of alkaloids is low. There is no significant difference between stem and leaf. In contrast, D. crepidatum is mainly composed of alkaloids and terpenoids, with crepidamine and dendrocrepine as its unique components, and there are great differences in the components between stems and leaves. This study provides a theoretical basis for the development and utilization of Dendrobium resources.
ABSTRACT
UDP glucosyltransferase (UDPGT) catalyzes the synthesis of secondary metabolites and plant hormones to regulate plant growth and development, pathogen defense and environmental adaptability. In this study 18 members of the RcUDPGT gene family were cloned from Tibetan Rhodiola crenulata and analyzed using bioinformatics. The tissue-specific expression, abiotic stresses and plant hormones (abscisic acid, auxin, methyl jasmonate) induced expression patterns were identified by real-time quantitative PCR. The bait vector of RcUDPGT (JX228125.1) was constructed to select interacting proteins from an Arabidopsis yeast library. The results of the bioinformatics analysis revealed that RcUDPGT nucleotide sequences were about 1 400 bp and encoded 452-498 amino acids. In the primary protein sequences, C-terminal sequences were more conserved compared with N-terminal regions, which held a PSPG (plant secondary product glycosyltransferase) domain. In the tertiary structures, RcUDPGTs contained a UDP sugar donor recognition binding site. In addition, all genes had multiple phosphorylation sites. The results of qRT-PCR showed that RcUDPGTs genes were expressed in root, stem and leaf. The expression levels were regulated by low temperature/ultraviolet light and various plant hormones (ABA, IAA, MeJA), but the expression patterns were quite different among them. For example, RcUDPGT6, RcUDPGT11, and RcUDPGT17 had the highest expression in leaves and were induced by all three hormones, suggesting that the functions of these genes might be to respond to environmental changes. RcUDPGT9, RcUDPGT10, RcUDPGT14 were most abundantly expressed in roots and were significantly induced by ABA and MeJA hormones, indicating that these genes may be involved in the synthesis and accumulation of salidroside. Yeast two-hybrid results showed that RcUDPGT did not exhibit autoactivation and cell toxicity, and two significant interactional genes were identified, AtKCR1 (AT1G67730.1) and AtSNL4 (AT1G70060). The AtKCR1 gene encodes a β-ketoacyl reductase (KCR) involved in synthesis of very long chain fatty acids. The AtSNL4 gene encodes a homolog of the transcriptional repressor SIN3, which could participate in the ABA hormone signaling pathway and enhance the transcriptional repression of AP2/EREBP class factors in Arabidopsis. These results suggest that the accumulation of the secondary metabolite salidroside in Rhodiola crenulata might be affected by several regulatory mechanisms. The above results may lay the foundation for understanding the adaptive mechanism of Rhodiola crenulata in a high altitude environment and stimulate an in-depth study of the synthesis and accumulation of secondary metabolites in this species.
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Decompression and curettage can result are effective as treatments for large jaw cysts, which are common diseases in the clinic. Based on a treatment used in a previous study, this paper proposes a "three-step method" to treat large jaw cyst and repair the bone defect by decompression, curettage, and autologous dental bone powder implantation. This paper introduces the processes and key points of the operation involved in the abovementioned method.
Subject(s)
Humans , Bone Cements , Bone Cysts , General Surgery , Bone Transplantation , Curettage , Jaw CystsABSTRACT
Objective: To investigate the effect of V600E mutation of v-raf murine sarcoma viral oncogene homolog B1 (BRAFV600E) gene silencing by RNA interference on the proliferation of papillary thyroid cancer cells. Methods: The plasmid vectors containing short hairpin RNA (shRNA) targeting BRAFV600E gene (BRAFV600E-shRNA) were transfected into papillary thyroid cancer CGTHW3 cells. The silencing efficiency of BRAFV600E-shRNA was measured by semi-quantitative reverse transcription-PCR (RT-PCR) and Western blotting, and the related proteins in mitogen extracellular kinase/extracellular signal-regulated kinase (MEK/ERK) signal pathway were detected by Western blotting. Then the proliferation and cell cycle distribution of CGTHW3 cells after BRAFV600EshRNA transfection were detected by MTT method and flow cytometry, respectively. Results: The expression levels of BRAFV600E mRNA and protein were significantly reduced in CGTHW3 cells transfected with specific shRNAs, and the expressions of Ras, phospho-MEK (p-MEK) and p-ERK proteins in MEK/ERK signal pathway were depressed (all P V600E-shRNA was significantly inhibited (P V600E-shRNA transfection group was higher than that in the blank control group, while the percentage of cells at S phase was reduced (both P V600E gene silencing can inhibit the proliferation of papillary thyroid cancer cells through blocking MEK/ERK signal pathway.
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Objective: To study the effect of metastasis suppressor gene Kail/CD82 on the cell proliferation of Hep-2 cell line. Methods: Recombinant adenovirus rAd-Kail was amplified, purified, and was used to transfect laryngo-carcinoma Hep-2 cell line. Cells transfected with blank vector and untransfected cells served as controls. MTT assay was used to assess the influence of Kail gene on proliferation of Hep-2 cells; RT-PCR was used to examine the expression of Kail gene in cells of different groups. Results: The titer of rAd-Kail reached 6 X 1010 PFU/ml after expansion and purification. When the concentration of the adenovirus was 30 MOI, the transfection rate of Hep-2 cells could be higher than 90%. MTT assay showed that the cell proliferation abilities were similar in the two control groups, and the proliferation ability of cells in the Kail transfection group was significantly lower than that in the non-transfected group (P<0. 05) ,with the inhibitory rate in the Kail group being 29%. Conclusion: The Kail/CD82 gene can inhibit the proliferation of Hep-2 cells.