http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Hu Yuanyuan,Wang Ling,Yang Ge,Wang Shanshan,Guo Miaomiao,Lu Hongzhao,Zhang Tao 한국유전학회 2023 Genes & Genomics Vol.45 No.11
Background The vitamin D receptor (VDR) mediates the pleiotropic biological actions that include osteoporosis, immune responses and androgen synthesis.VDR is widely expressed in testis cells such as Leydig cells, Sertoli cells, and sperm. The levels of steroids are critical for sexual development. In the early stage of steroidogenesis, cholesterol is converted to pregnenolone (precursor of most steroid hormones) by cholesterol side-chain lyase (CYP11A1), which eventually synthesizes the male hormone testosterone. Objective This study aims to reveal how VDR regulates CYP11A1 expression and affects testosterone synthesis in murine Leydig cells. Methods The levels of VDR, CYP11A1 were determined by quantitative real-time polymerase chain reaction (RT-qPCR) or western blot. Targeted relationship between VDR and Cyp11a1 was evaluated by dual-luciferase reporter assay. The levels of testosterone concentrations in cell culture media serum by enzyme-linked immunosorbent assay (ELISA). Results Phylogenetic and motif analysis showed that the Cyp11a1 family had sequence loss, which may have special biological functions during evolution. The results of promoter prediction showed that vitamin D response element (VDRE) existed in the upstream promoter region of murine Cyp11a1. Dual-luciferase assay confirmed that VDR could bind candidate VDREs in upstream region of Cyp11a1, and enhance gene expression. Tissue distribution and localizatio analysis showed that Cyp11a1 was mainly expressed in testis, and dominantly existed in murine Leydig cells. Furthermore, over-expression VDR and CYP11A1 significantly increased testosterone synthesis in mice Leydig cells. Conclusions Active vitamin D3 (VD3) and Vdr interference treatment showed that VD3/VDR had a positive regulatory effect on Cyp11a1 expression and testosterone secretion. VDR promotes testosterone synthesis in male mice by up-regulating Cyp11a1 expression, which played an important role for male reproduction.
Novel Single Switch DC-DC Converter for High Step-Up Conversion Ratio
Hu, Xuefeng,Gao, Benbao,Huang, Yuanyuan,Chen, Hao The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3
This paper presents a new structure for a step up dc-dc converter, which has several advantageous features. Firstly, the input dc source and the clamped capacitor are connected in series to transfer energy to the load through dual voltage multiplier cells. Therefore, the proposed converter can produce a very high voltage and a high conversion efficiency. Secondly, a double voltage clamped circuit is introduced to the primary side of the coupled inductor. The energy of the leakage inductance of the coupled inductor is recycled and the inrush current problem of the clamped circuits can be shared equally by two synchronous clamped capacitors. Therefore, the voltage spike of the switch tube is solved and the current stress of the diode is reduced. Thirdly, dual voltage multiplier cells can absorb the leakage inductance energy of the secondary side of the coupled inductor to obtain a higher efficiency. Fourthly, the active switch turns on at almost zero current and the reverse-recovery problem of the diodes is alleviated due to the leakage inductance, which further improves the conversion efficiency. The operating principles and a steady-state analysis of the continuous, discontinuous and boundary conduction modes are discussed in detail. Finally, the validity of this topology is confirmed by experimental results.
Novel Single Switch DC-DC Converter for High Step-Up Conversion Ratio
Xuefeng Hu,Benbao Gao,Yuanyuan Huang,Hao Chen 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3
This paper presents a new structure for a step up dc-dc converter, which has several advantageous features. Firstly, the input dc source and the clamped capacitor are connected in series to transfer energy to the load through dual voltage multiplier cells. Therefore, the proposed converter can produce a very high voltage and a high conversion efficiency. Secondly, a double voltage clamped circuit is introduced to the primary side of the coupled inductor. The energy of the leakage inductance of the coupled inductor is recycled and the inrush current problem of the clamped circuits can be shared equally by two synchronous clamped capacitors. Therefore, the voltage spike of the switch tube is solved and the current stress of the diode is reduced. Thirdly, dual voltage multiplier cells can absorb the leakage inductance energy of the secondary side of the coupled inductor to obtain a higher efficiency. Fourthly, the active switch turns on at almost zero current and the reverse-recovery problem of the diodes is alleviated due to the leakage inductance, which further improves the conversion efficiency. The operating principles and a steady-state analysis of the continuous, discontinuous and boundary conduction modes are discussed in detail. Finally, the validity of this topology is confirmed by experimental results.
Effect of light quality on regeneration and naphthoquinones accumulation of Arnebia euchroma
Jia Hu,Yao Leng,Yuanyuan Jiang,Su Ni,Li Zhang 한국식물생명공학회 2019 Plant biotechnology reports Vol.13 No.4
The influence of light quality on the regeneration (i.e., formation, proliferation, growth, development, and rooting) and naphthoquinones’ accumulation of Arnebia euchroma was investigated in vitro. The cotyledons of sterile seedings were placed on modified LS medium supplemented with 0.8 mg/L thidiazuron to obtain callus, which was incubated on the corresponding medium at different culture stages under varying light conditions, including dark, fluorescent lamp (Fl), white light-emitting diodes (LEDs), blue LEDs, red LEDs, and a combination of 25% red, 25% blue, and 50% white LEDs [RBW (1:1:2)]. During the establishment of the A. euchroma regeneration system, we obtained the maximum fresh weight, dry weight, germination rate, shoot number, and proliferation rate under RBW (1:1:2) LEDs in the formation and multiplication phases; the growth index, shoot height, leaf number, and photosynthetic pigment concentration were promoted under red LEDs in the growth and development phase; and the maximum rooting rate (89.29% ± 2.06%) was observed under red LEDs in the rooting phase. To study the effect of light quality on naphthoquinones’ accumulation of A. euchroma, we used the euphylla to achieve adventitious roots, and the highest shikonin (121.77 ± 6.68 μg/g DW) and β′β-dimethylacrylalkannin (619.18 ± 15.71 μg/g DW) contents were detected in the dark culture. The lowest naphthoquinone contents were recorded under Fl in the adventitious roots. Overall, RBW (1:1:2) LEDs enhanced A. enchroma formation and proliferation, while red LEDs promoted the plant’s growth, development, and rooting. The dark condition was beneficial to naphthoquinones’ accumulation, whereas the light condition inhibited the naphthoquinones production of A. enchroma adventitious roots. Determining the suitable light quality for the regeneration and accumulation of naphthoquinones that is conducive to the protection and promotes resource utilization is essential.
Xiaolin Hu,Yuanyuan Li,Jian Tian,Hongru Yang,Hongzhi Cui 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.45 No.-
Finding a photocatalyst that can utilize the full solar spectrum is paramount importance inphotocatalysis. Assembling TiO2 with a narrow bandgap semiconductor to form a heterostructurewhich can harvest the light from UV to near-infrared (NIR) region would be ideal for photocatalysis. Here, we report the synthesis of Ag2S quantum dots (QDs)/TiO2 nanobelt heterostructures to display theUV-visible-NIR full spectrum photocatalytic property. The enhanced photocatalytic performance isascribed to the efficient charge separation properties of the heterostructure formed by intimate contactbetween Ag2S and TiO2, and efficient visible and NIR harvesting of Ag2S QDs on the surface of TiO2nanobelts.
( Enkhtuya Bayar ),( Yuanyuan Ren ),( Yinghua Chen ),( Yafang Hu ),( Shuncheng Zhang ),( Xuelian Yu ),( Jun Fan ) 한국미생물 · 생명공학회 2021 Journal of microbiology and biotechnology Vol.31 No.12
Tobacco etch virus protease (TEVp) is a useful tool for removing fusion tags, but wild-type TEVp is less stable under oxidized redox state. In this work, we introduced and combined C19S, C110S and C130S into TEVp variants containing T17S, L56V, N68D, I77V and S135G to improve protein solubility, and S219V to inhibit self-proteolysis. The solubility and cleavage activity of the constructed variants in Escherichia coli strains including BL21(DE3), BL21(DE3)pLys, Rossetta(DE3) and Origami(DE3) under the same induction conditions were analyzed and compared. The desirable soluble amounts, activity, and oxidative stability were identified to be reluctantly favored in the TEVp. Unlike C19S, C110S and C130S hardly impacted on decreasing protein solubility in the BL21(DE3), but they contributed to improved tolerance to the oxidative redox state in vivo and in vitro. After two fusion proteins were cleaved by purified TEVp protein containing double mutations under the oxidized redox state, the refolded disulfide-rich bovine enterokinase catalytic domain or maize peroxidase with enhanced yields were released from the regenerated amorphous cellulose via affinity absorption of the cellulose-binding module as the affinity tag.
Li Chaoqiong,Hu Lizong,Que Beibei,Hu Yueran,Guo Yuanyuan,Zhang Minghui,Wang Zenan,Wang Xueqin,Liu Hongzhan,Wang Junsheng,Tian Huihui,Li Xiaoli 한국유전학회 2021 Genes & Genomics Vol.43 No.8
Background Paeonia ostii seeds were identifed as novel sources of edible plant oil with a high proportion of α-linolenic acid, a type of n-3 fatty acid with many health benefts. Due to the unreliability of seed oil content and quality, it is necessary to discover the mechanism underlying lipid biosynthesis in Paeonia ostii seeds. Objectives This study aimed to identify the key genes involved in lipid biosynthesis in Paeonia ostii seeds by analyzing the relationship among the seed characteristics and the expression patterns of lipid genes in Paeonia ostii during seed development. Methods Preliminary research on Paeonia ostii seed development was carried out from 10 days after pollination until maturity, focusing on phenology, oil content and lipid profles. In addition, we investigated the spatiotemporal expression of 36 lipid biosynthetic genes in Paeonia ostii by using quantitative real-time PCR. Results The results suggested that the development of Paeonia ostii seeds from pollination to maturity could be divided into three periods. The 36 lipid genes showed various spatiotemporal expression patterns and fve gene groups with distinct temporal patterns during seed development were identifed by clustering analysis of expression data. Furthermore, the relationships between gene expression and lipid/fatty acid accumulation and some candidate key lipid genes were discussed. Conclusions This study provided the global patterns of fatty acid and lipid biosynthesis-related gene expression, which are critical to understanding the molecular basis of lipid biosynthesis and identifying the lipid accumulation rate-limiting genes during seed development.