Cloning and Expression of the Duck Leptin Gene and the Effect of Leptin on Food Intake and Fatty Deposition in Mice

Dai, Han Chuan,Long, Liang Qi,Zhang, Xiao Wei,Zhang, Wei Min,Wu, Xiao Xiong Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.6

Leptin is the adipocyte-specific product of the obese gene and plays a major role in food intake and energy metabolism. Leptin research was mainly focused on mammalian species, but understanding of leptin and its function in poultry is very poor. In this study, the duck leptin gene was amplified using the reverse transcription-polymerase chain reaction (RT-PCR) from duck liver RNA. The cDNA fragment was inserted into the pET-28a expression vector, and the resulting plasmid was expressed in Escherichia coli BL21 (DE3). Experimental mice were given an intraperitoneal injection of 10 mg/kg leptin dissolved in phosphate buffered saline (PBS), while the control mice were injected with PBS. The effect of leptin on food intake, body weight and fatty deposition in mice was detected. Sequence analysis revealed that duck leptin had a length of 438 nucleotides which encoded a peptide with 146 amino acid residues. The sequence shares highly homology to other animals. The coding sequence of duck leptin was 84 and 86% identical to human and pig leptin nucleotides sequence. Highest identity was with the rat coding sequence (95%). The identity of the amino acid sequence was 84, 82 and 96% respectively compared to that of the human, pig and rat. Results of SDS-PAGE analysis indicated that a fusion protein was specifically expressed in E. coli BL21 (DE3). The purified product was found to be biologically active during tests. Continuous administration of recombinant duck leptin inhibited food intake. Despite the decrease of food intake, leptin significantly induced body weight and fatty deposition. These changes were accompanied by a significant down-secretion of plasma glucose, cholesterol, triglyceride and insulin levels in mice. The observations provide evidence for an inhibitory effect of leptin in the regulation of food intake and for a potential role of duck leptin in the regulation of lipogenesis.

Protective Effects of Scutellaria barbata Against Rat Liver Tumorigenesis

Dai, Zhi-Jun,Wu, Wen-Ying,Kang, Hua-Feng,Ma, Xiao-Bin,Zhang, Shu-Qun,Min, Wei-Li,Lu, Wang-Feng,Lin, Shuai,Wang, Xi-Jing Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is used to treat cancers, inflammation, and urinary diseases. This study aimed to determine any protective effects of S. barbata crude extract (CE-SB) against rat liver tumorigenesis induced by diethylnitrosamine (DENA). Liver malfunction indices in serum were measured by biochemical examination. Hematoxylin and eosin staining was performed to examine liver pathology. Contents of malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in liver homogenates to evaluate oxidative stress. The levels of liver malfunction indices in the CE-SB groups, especially in the CE-SB high dose group, were lower than that of the model group (P<0.05). The results from histological examination indicated that the number of liver nodules in the CE-SB groups decreased compared with the model group (P<0.05). Content of MDA determined in liver was significantly decreased, and level of SOD elevated by CE-SB. CE-SB can inhibit experimental liver tumorigenesis and relieve hepatic injury in rats.

Fabrication and magnetic properties of hexagonal BaFe12O19 ferrite obtained by magnetic-field-assisted hydrothermal process

Min Zhang,Jianming Dai,Qiangchun Liu,Qiang Li,Zhenfa Zi 한국물리학회 2018 Current Applied Physics Vol.18 No.11

High magnetic field effects on the microstructure and magnetic properties of BaFe12O19 hexaferrites synthesized hydrothermal method have been investigated. The obtained results indicate that the lattice constant decreases gradually as the magnetic field strength increases, which may be attributed to the lattice distortion resulted from the high magnetic field. Polycrystalline BaFe12O19 samples prepared under magnetic field strength at zero and 5 T are single phase. It is found that application of external magnetic field during synthesis can induce orientated growth of the hexaferrite crystals along the easy magnetic axis. The magnetic properties can be effectively regulated by an application of high magnetic fields. It is observed that the BaFe12O19 prepared under a 5 T magnetic field exhibits a higher room-temperature saturation magnetization (66.3 emu/g) than that of the sample (43.6 emu/g) obtained without magnetic field. The results can be explained as the enhanced crystalline, improvement of Fe3+ ions occupancy and the oriented growth induced by the external magnetic field. The growing orientation of particles gives rise to increased coercivity due to the enhancement in shape anisotropy. It is expected that an application of magnetic field during the formation of magnetic nanoparticles could be a promising technique to modify magnetic properties with excellent performance.

Mitochondrial Genome Microsatellite Instability and Copy Number Alteration in Lung Carcinomas

Dai, Ji-Gang,Zhang, Zai-Yong,Liu, Quan-Xing,Min, Jia-Xin Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

Objective: Mitochondrial DNA (mtDNA) is considered a hotspot of mutations in various tumors. However, the relationship between microsatellite instability (MSI) and mtDNA copy number alterations in lung cancer has yet to be fully clarifieds. In the current study, we investigated the copy number and MSI of mitochondrial genome in lung carcinomas, as well as their significance for cancer development. Methods: The copy number and MSI of mtDNA in 37 matched lung carcinoma/adjacent histological normal lung tissue samples were examined by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) assays for sequence variation, followed by sequence analysis and fluorogenic 5'-nuclease real-time PCR. Student's t test and linear regression analyses were employed to analyze the association between mtDNA copy number alterations and mitochondrial MSI (mtMSI). Results: The mean copy number of mtDNA in lung carcinoma tissue samples was significantly lower than that of the adjacent histologically normal lung tissue samples (p<0.001). mtMSI was detected in 32.4% (12/37) of lung carcinoma samples. The average copy number of mtDNA in lung carcinoma samples containing mtMSI was significantly lower than that in the other lung carcinoma samples (P<0.05). Conclusions: Results suggest that mtMSI may be an early and important event in the progression of lung carcinogenesis, particularly in association with variation in mtDNA copy number.

Indium doping effect on the magnetic properties of Y-type hexaferrite Ba0.5Sr1.5Zn2(Fe1-xInx)12O22

Min Zhang,Lihua Yin,Qiangchun Liu,Zhenfa Zi,Jianming Dai,Yuping Sun 한국물리학회 2018 Current Applied Physics Vol.18 No.9

The effect of indium doping on structural and magnetic properties of Y-type hexaferrite Ba0.5Sr1.5Zn2(Fe1- xInx)12O22 (x=0, 0.02, 0.04, 0.06, 0.08 and 0.1) prepared by the solid state reaction method was investigated. The Rietveld refinement method was used to analyze the X-ray diffraction patterns. The magnetic transition temperatures associated with the proper-screw spin phase to the collinear ferrimagnetic spin phase transition can be efficiently modulated by varying indium content. The magnetic transition temperature increases to a maximum with indium content x=0.04 and then decreases with x, suggesting the possibility that electrically controlled magnetization reversal can be can be effectively tailored by varying indium content. The saturation magnetization at room temperature was decreased as increasing indium content, which can be explained as the metal ions occupation. It is worthy to note that the coercivity of In-doped samples was decreased drastically compared that of undoped sample, which is probably resulted from the reduction in anisotropy field with substitution of In3+ for Fe3+. The In-doped hexaferrite Ba0.5Sr1.5Zn2(Fe1-xInx)12O22 may be potential candidates for application in magnetoelectric devices.

The evaluation of online course of Traditional Chinese Medicine for Medical Bachelor, Bachelor of Surgery international students during the COVID-19 epidemic period

Zhang Qing,He Yi-Jing,Zhu Yu-Hang,Dai Min-Chen,Pan Man-Man,Wu Jia-Qi,Zhang Xian,Gu Ying-Er,Wang Fang-Fang,Xu Xiang-Rong,Qu Fan 한국한의학연구원 2020 Integrative Medicine Research Vol.9 No.3

Background: During the COVID-19 epidemic period, Traditional Chinese Medicine (TCM) course for international students of Medical Bachelor, Bachelor of Surgery (MBBS) program in Zhejiang University has shifted from traditional classroom to online environment. This study aimed to investigate MBBS international students’ perception on online TCM course, and to assess the online learning efficacy. Methods: A total of 84 MBBS international students attending course of “Basic Traditional Chinese Medicine” during 2020 academic years at Zhejiang University were enrolled in this study. A quantitative questionnaire was respectively completed before and after the TCM course using a pretest–post-test design. By means of two online learning platforms, Learning in ZJU and DingTalk, TCM course was broadcast in both live and archived format to students. Results: A total of 48 participants completed both baseline and follow-up questionnaires. The majority of participants preferred face-to-face classroom learning (26, 54.17% of total) when compared with online learning. Students felt that the course had brought in much benefits (mean 3.88, SD 0.87), and they were satisfied with the course content (mean 3.83, SD 0.95). Students’ TCM related knowledge and their behaviors of discussion and consulting were significantly improved by online TCM course (all P < 0.001). Students’ awareness of the necessity of TCM education and their feeling of difficulty in learning TCM were significantly strengthened (P = 0.042, 0.025, respectively). Conclusion: Online learning is a good alternative for TCM course of MBBS international students when classroom learning is suspended, whereas it cannot replace the need for onsite and face-to-face learning.

A New Ferulic Acid Ester and Other Constituents from Dracocephalum peregrinum

Dai, Li-Min,Zhao, Chun-Chao,Jin, Hui-Zi,Tang, Jian,Shen, Yun-Heng,Li, Hui-Liang,Peng, Cai-Yon,Zhang, Wei-Dong 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.10

A new ferulic acid ester, 1'-methyl-2'-hydroxyethyl ferulate (1), together with methylcaffeate (2), 4-hydroxy cinnamic acid (3), ferulic acid (4), caffeic acid (5), diosmetin (6), luteolin (7), 5,3',4'-trihydroxy-3,7-dimethoxyflavone (8), eriodictyol (9), kaempferol (10), quercetin (11), acacetin-7-O-glcopyranoside (12), 4-($\beta$-glucopyranosyloxy) benzoic acid (13), luteolin-7-O-(6"-feruloyl) glucopyranoside (14), luteolin-7-O-glucopyranoside (15), kaempferide-3-O-rhamnopyranoside (16), quercitrin (17), kaempferol-3-O-glucopyranoside (18), prunasin (19), quercetin-7-O-glucopyranoside (20), quercetin-3-O-glucopyranoside (21), plantaginin (22), linarin (23), luteolin-7-O-rutinoside (24), and chlorogenic acid (25) were isolated from the aerial parts of Dacocephalum peregrinum. The structure of 1 was elucidated on the basis of spectroscopic and HR-ESI-MS analyses. In addition, compound 1 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.

Hybrid functional study on optical properties of Sr2M2O7xNx(M ¼ Nb, Ta) photocatalysts with perovskite-slab structures

Yu-Min Song,Jian-Qing Dai,Hu Zhang 한국물리학회 2016 Current Applied Physics Vol.16 No.1

We present the electronic, dielectric, and optical properties of layered perovskite pure and N-doped Sr2M2O7 (M ¼ Nb and Ta) based on density functional theory with the HSE06 approximation. The band gaps for pure Sr2M2O7 (M ¼ Nb and Ta) are consistent with the experimental data. Optical properties are obtained and compared with the experimental results. Pure Sr2Nb2O7 and Sr2Ta2O7 have broad applications in photocatalysis in the ultra-violet region. In contrast with Sr2Ta2O7, the absorption ability of Sr2Nb2O7 is slightly stronger. The N doping in Sr2Nb2O7 shifts the light absorption boundary into the visible region. The optical absorption effect of Sr2Nb2O5N2 is better than Sr2Nb2O6.5N0.5 in the visible region. The N doping in Sr2Ta2O7 reduces the band gap and produces visible light absorptions. Sr2Ta2O5N2 shows higher absorption effect in the visible light region than Sr2Ta2O6.5N0.5.

A New Ferulic Acid Ester and Other Constituents from Dracocephalum peregrinum

Li-Min Dai,Chun-Chao Zhao,Hui-zi Jin,Yun-Heng Shen,Hui-Liang Li,Cai-Yun Peng,Jian Tang,Wei-Dong Zhang 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.10

A new ferulic acid ester, 1'-methyl-2'-hydroxyethyl ferulate (1), together with methylcaffeate (2), 4- hydroxy cinnamic acid (3), ferulic acid (4), caffeic acid (5), diosmetin (6), luteolin (7), 5,3',4'-trihydroxy- 3,7-dimethoxyflavone (8), eriodictyol (9), kaempferol (10), quercetin (11), acacetin-7-Oglcopyranoside (12), 4-(β-glucopyranosyloxy) benzoic acid (13), luteolin-7-O-(6''-feruloyl) glucopyranoside (14), luteolin-7-O-glucopyranoside (15), kaempferide-3-O-rhamnopyranoside (16), quercitrin (17), kaempferol-3-O-glucopyranoside (18), prunasin (19), quercetin-7-O-glucopyranoside (20), quercetin-3-O-glucopyranoside (21), plantaginin (22), linarin (23), luteolin-7-O-rutinoside (24), and chlorogenic acid (25) were isolated from the aerial parts of Dacocephalum peregrinum. The structure of 1 was elucidated on the basis of spectroscopic and HR-ESI-MS analyses. In addition, compound 1 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.

Compatibility effects of ginseng and Ligustrum lucidum Ait herb pair on hematopoietic recovery in mice with cyclophosphamide-induced myelosuppression and its material basis

Jiahong Han,Min Dai,Yan Zhao,Enbo Cai,Lianxue Zhang,Xiaohuan Jia,Nian Sun,Xuan Fei,Hui Shu 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.2

Background: Ginseng (G) and Ligustrum lucidum Ait (LLA) are core traditional Chinese medicines intreating myelosuppression formula. The present study was designed to profile effect of G and LLA herbpair (G-LLA) on myelosuppressed mice. Methods: The mice myelosuppression model was established by intraperitoneal (i.p.) injection ofcyclophosphamide (Cy). Hematopoietic function of bone marrow was measured by hemopoietic progenitorcell culture and peripheral blood count, and serum hemopoietic factors were tested by enzymelinkedimmunosorbent assay. Bone marrow cell cycle was performed by flow cytometry. HPLC was usedto measure 20 potential chemical components related to myelosuppression, including ginsenoside Rg1,Re, Rb1, Rc, Rb2, Rb3, Rd, Rk3, Rh4, 20 (S)-Rg3, 20 (R)-Rg3, Rk1, Rg5, salidroside, and so on. Results: G, LLA, and G-LLA improved the amount of peripheral blood cells and bone marrow cellsof myelosuppressed mice (P < 0.01). They significantly increased the colony quantity of colony-formingunitegranulocyte macrophage, burst-forming unit erythroid, colony-forming unit erythroid, and colony-forming unit megakaryocyte and amount of G2/M and S phase cells (P < 0.01). They also significantlydecreased the amount of hematopoiesis-related cytokines (P < 0.01). The content of chemicalcomponents in G-LLA changed, and the change of rare saponin was the most obvious. Conclusion: These results show that G-LLA herb pair might produce synergistic or complementarycompatibility effects on bone marrow suppression after chemotherapy. It suggests that the substancebasis of G-LLA for treating bone marrow suppression may be effective chemical components.