A Circuit Simulation Model for An Uitra-fast IGBT And Analysis of Parameter Sensitivity

Ai-min Li,Xiang-ning He,Zhao-ming Qian 전력전자학회 1995 ICPE(ISPE)논문집 Vol.1995 No.10

Based on existing built-in models of PSpice, by the composite model principle, a composite Insulated Gate Bipolar Transistor (IGBT) model for an ultra-fast IGBT is presented Comparison between measurement and simulation results shows good agreement in transient and steady-state behaviour of the IGBT Parametric sentive analysis of this model is performed, and validity of the composite model is discussed.

Mangiferin Induces Apoptosis by Regulating Bcl-2 and Bax Expression in the CNE2 Nasopharyngeal Carcinoma Cell Line

Pan, Li-Li,Wang, Ai-Yan,Huang, Yong-Qi,Luo, Yu,Ling, Min Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.17

To investigate the anti-proliferative mechanism of mangiferin in a human nasopharyngeal carcinoma cell line, CNE2 cells were incubated with different concentrations of mangiferin (12.5, 25, 50, 100, 150 and $200{\mu}M$) or with PBS as a control for 72 hours. Analyses were made of the cell cycle and apoptosis with measurement of mRNA and protein levels of two apoptosis-related genes, Bcl-2 and Bax. Flow cytometry assays showed mangiferin could inhibit CNE2 cell proliferation via G2/M arrest and induction of early apoptosis. Real time PCR and Western blotting showed the mRNA and protein level of Bcl-2 to be down-regulated, while those of Bax were upregulated, when CNE2 cells were treated with mangiferin. This investigation indicated anti-proliferation effects of mangiferin through induction of cell apoptosis regulated by Bcl-2 and Bax expression.

MR Imaging of the Spine at 3.0T with T2-Weighted IDEAL Fast Recovery Fast Spin-Echo Technique

Ai-Jun Ren,Yong Guo,Shu-Ping Tian,Li-Jing Shi,Min-Hua Huang 대한영상의학회 2012 Korean Journal of Radiology Vol.13 No.1

Objective: To compare the iterative decomposition of water and fat with echo asymmetry and the least-squares estimation (IDEAL) method with a fat-saturated T2-weighted (T2W) fast recovery fast spin-echo (FRFSE) imaging of the spine. Materials and Methods: Images acquired at 3.0 Tesla (T) in 35 patients with different spine lesions using fat-saturated T2W FRFSE imaging were compared with T2W IDEAL FRFSE images. Signal-to-noise ratio (SNR)-efficiencies measurements were made in the vertebral bodies and spinal cord in the mid-sagittal plane or nearest to the mid-sagittal plane. Images were scored with the consensus of two experienced radiologists on a four-point grading scale for fat suppression and overall image quality. Statistical analysis of SNR-efficiency, fat suppression and image quality scores was performed with a paired Student’s t test and Wilcoxon’s signed rank test. Results: Signal-to-noise ratio-efficiency for both vertebral body and spinal cord was higher with T2W IDEAL FRFSE imaging (p < 0.05) than with T2W FRFSE imaging. T2W IDEAL FRFSE demonstrated superior fat suppression (p < 0.01) and image quality (p < 0.01) compared to fat-saturated T2W FRFSE. Conclusion: As compared with fat-saturated T2W FRFSE, IDEAL can provide a higher image quality, higher SNR-efficiency, and consistent, robust and uniform fat suppression. T2W IDEAL FRFSE is a promising technique for MR imaging of the spine at 3.0T. Objective: To compare the iterative decomposition of water and fat with echo asymmetry and the least-squares estimation (IDEAL) method with a fat-saturated T2-weighted (T2W) fast recovery fast spin-echo (FRFSE) imaging of the spine. Materials and Methods: Images acquired at 3.0 Tesla (T) in 35 patients with different spine lesions using fat-saturated T2W FRFSE imaging were compared with T2W IDEAL FRFSE images. Signal-to-noise ratio (SNR)-efficiencies measurements were made in the vertebral bodies and spinal cord in the mid-sagittal plane or nearest to the mid-sagittal plane. Images were scored with the consensus of two experienced radiologists on a four-point grading scale for fat suppression and overall image quality. Statistical analysis of SNR-efficiency, fat suppression and image quality scores was performed with a paired Student’s t test and Wilcoxon’s signed rank test. Results: Signal-to-noise ratio-efficiency for both vertebral body and spinal cord was higher with T2W IDEAL FRFSE imaging (p < 0.05) than with T2W FRFSE imaging. T2W IDEAL FRFSE demonstrated superior fat suppression (p < 0.01) and image quality (p < 0.01) compared to fat-saturated T2W FRFSE. Conclusion: As compared with fat-saturated T2W FRFSE, IDEAL can provide a higher image quality, higher SNR-efficiency, and consistent, robust and uniform fat suppression. T2W IDEAL FRFSE is a promising technique for MR imaging of the spine at 3.0T.

Theoretical Study of the Relationships between Excited State Geometry Changes and Emission Energies of Oxyluciferin

Li, Zhong-Wei,Min, Chun-Gang,Ren, Ai-Min,Guo, Jing-Fu,Goddard, John D.,Feng, Ji-Kang,Zuo, Liang Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.4

In order to find a relationship between firefly luciferases structure and bioluminescence spectra, we focus on excited substrate geometries which may be affected by rigid luciferases. Density functional theory (DFT) and time dependent DFT (TDDFT) were employed. Changes in only six bond lengths of the excited substrate are important in determining the emission spectra. Analysis of these bonds suggests the mechanism whereby luciferases restrict more or less the excited substrate geometries and to produce multicolor bioluminescence.

Contributed Mini Review : Isoforms, structures, and functions of versatile spectraplakin MACF1

( Li Fang Hu ),( Pei Hong Su ),( Run Zhi Li ),( Chong Yin ),( Yan Zhang ),( Peng Shang ),( Tuan Min Yang ),( Ai Rong Qian ) 생화학분자생물학회(구 한국생화학분자생물학회) 2016 BMB Reports Vol.49 No.1

Spectraplakins are crucially important communicators, linking cytoskeletal components to each other and cellular junctions. Microtubule actin crosslinking factor 1 (MACF1), also known as actin crosslinking family 7 (ACF7), is a member of the spectraplakin family. It is expressed in numerous tissues and cells as one extensively studied spectraplakin. MACF1 has several isoforms with unique structures and well-known function to be able to crosslink F-actin and microtubules. MACF1 is one versatile spectraplakin with various functions in cell processes, embryo development, tissue-specific functions, and human diseases. The importance of MACF1 has become more apparent in recent years. Here, we summarize the current knowledge on the presence and function of MACF1 and provide perspectives on future research of MACF1 based on our studies and others. [BMB Reports 2016; 49(1): 37-44]

Correlation of Histological Examination of Meniscus with MR Images: Focused on High Signal Intensity of the Meniscus Not Caused by Definite Meniscal Tear and Impact on MR Diagnosis of Tears

Chun Ai Li,Min Ki Kim,김인환,이주홍,장규윤,이상용 대한영상의학회 2013 Korean Journal of Radiology Vol.14 No.6

Objective: To document the causes of high signal intensity of the meniscus which is not caused by definite meniscal tears on MR imaging, through correlation with histological examination. Materials and Methods: For the correlation between the MR image and histology, we obtained prospectively 31 meniscal specimens from 21 patients. Proton density-weighted turbo spin-echo MR images were used. Minimal tear, thinning of the lamellar layer, degeneration of the central layer, and radial tie fibers were detected upon histological examination, and were correlated with the corresponding MR images. Results: Minimal tear of the lamellar layer was seen in 60 zones out of 100 slides. On MR images, 29 (48.3%) of these 60 zones had high signal intensity. Thinning of the lamellar layer was seen in 24 zones, with 7 (29.2%) having high signal intensity. 57 central zones showed degenerative change in the central layer and high signal intensity on all corresponding MR images. Radial tie fibers in the central layer appeared as high signal intensity areas. Conclusion: Minimal tear and thinning of the lamellar layer, degeneration and radial tie fibers of the central layer of the meniscus cause high signal intensity on MR images.

miR-140-3p Knockdown Suppresses Cell Proliferation and Fibrogenesis in Hepatic Stellate Cells via PTEN-Mediated AKT/mTOR Signaling

Shi-Min Wu,Tian-Hong Li,Hao Yun,Hong-Wu Ai,Ke-Hui Zhang 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.6

Purpose: Liver fibrosis is a major cause of morbidity and mortality and the outcome of various chronic liver diseases. Activationof hepatic stellate cells (HSCs) is the key event in liver fibrosis. Studies have confirmed that miR-140-3p plays a potential regulatoryeffect on HSC activation. However, whether miR-140-3p mediates the liver fibrosis remains unknown. Materials and Methods: Expression of miR-140-3p was detected by real-time quantitative PCR (qPCR). Cell proliferation wasmeasured by MTT, while cell apoptosis rate was determined via flow cytometry. Western blot assay was used to detect the expressionof cleaved PARP. The fibrogenic effect was evaluated by expression of α-smooth muscle actin and desmin. Functional experimentswere performed in transforming growth factor β1 (TGF-β1)-induced HSC-T6 cells with transfection of anti-miR-140-3pand/or siPTEN. Target binding between miR-140-3p and PTEN was predicted by the TargetScan database and identified usingluciferase reporter assay and RNA immunoprecipitation. Results: TGF-β1 induced the activation of HSC-T6 cells, and miR-140-3p expression varied according to HSC-T6 cell activationstatus. Knockdown of miR-140-3p reduced cell proliferation and the expressions of α-SMA and desmin, as well as increasedapoptosis, in TGF-β1-induced HSC-T6 cells, which could be blocked by PTEN silencing. Additionally, inactivation of the AKT/mTOR signaling pathway stimulated by miR-140-3p knockdown was abolished when silencing PTEN expression. PTEN was negativelyregulated by miR-140-3p via direct binding in HSC-T6 cells. Conclusion: miR-140-3p is an important mediator in HSC-T6 cell activation, and miR-140-3p knockdown suppresses cell proliferationand fibrogenesis in TGF-β1-induced HSC-T6 cells, indicating that miR-140-3p may be a potential novel molecular targetfor liver fibrosis.

Efficacy and safety of herbal medicine (Binafuxi granules) for the common cold with fever: A multicenter, randomized, double-blind, placebo-controlled, phase II clinical trial

Liu Xuemei,Min Jie,She Bin,Chen Yang,Li Jun,Huang Lei,Chen Ju,Luo Ai,Mei Yang,Li Ting,Wu Yanqing,Chen Daohong,Hongli Zhong,Liu Wei,Mao Bing,Jiang Hongli 한국한의학연구원 2023 Integrative Medicine Research Vol.12 No.3

Background: Binafuxi granules are a traditional Uighur medicine (TUM) for treating the common cold with fever. However, high-quality clinical studies supporting its efficacy and safety are lacking. Methods: In this multicenter, randomized, double-blind, placebo-controlled, phase II clinical trial, patients with common cold and fever were randomly assigned to a high-dose group, low-dose group, and placebo group in a 1:1:1 ratio. Outcomes were time to fever relief, time to fever clearance, proportion of afebrile patients, time to symptom disappearance, rate of symptom disappearance, effective rate, emergency drug usage and safety assessment. Results: A total of 235 patients were recruited. Of these, 234 were included in the full analysis set (FAS), and 217 were included in the per-protocol set (PPS). In the FAS analysis, the median time to fever relief was 6.00 h, 5.54 h and 10.65 h (P = 0.31) in the high-dose group, low-dose group and placebo group, respectively. The median time to fever clearance was 18.29 h, 20.08 h and 25.00 h (P = 0.0018), respectively, and the proportion of afebrile patients was 92.4%, 89.7% and 71.4% (P = 0.0002), respectively. There was a significant difference in the disappearance time and disappearance rate of all symptoms and of individual symptoms. No serious adverse events were found. Conclusions: Binafuxi granules can dose-dependently shorten the fever course and improve clinical symptoms in patients suffering from the common cold with fever.

The GntR-Type Regulators GtrA and GtrB Affect Cell Growth and Nodulation of Sinorhizobium meliloti

Yi Wang,Ai-Min Chen,Ai-Yuan Yu,Li Luo,Guan-Qiao Yu,Jia-Bi Zhu,Yan-Zhang Wang 한국미생물학회 2008 The journal of microbiology Vol.46 No.2

GntR-type transcriptional regulators are involved in the regulation of various biological processes in bacteria, but little is known about their functions in Sinorhizobium meliloti. Here, we identified two GntR-type transcriptional regulator genes, gtrA and gtrB, from S. meliloti strain 1021. Both the gtrA1 mutant and the gtrB1 mutant had lower growth rates and maximal cell yields on rich and minimal media, as well as lower cell motility on swimming plates, than did the wild-type strain. Both mutants were also symbiotically deficient. Alfalfa plants inoculated with wild-type strain 1021 formed pink elongated nodules on primary roots. In contrast, the plants inoculated with the gtrA1 and gtrB1 mutants formed relatively smaller, round, light pink nodules mainly on lateral roots. During the first 3~4 weeks post-inoculation, the plants inoculated with the gtrA1 and gtrB1 mutants were apparently stunted, with lower levels of nitrogenase activity, but there was a remarkable increase in the number of nodules compared to those inoculated with the wild-type strain. Moreover, the gtrA1 and gtrB1 mutants not only showed delayed nodulation, but also showed markedly reduced nodulation competition. These results demonstrated that both GtrA and GtrB affect cell growth and effective symbiosis of S. meliloti. Our work provides new insight into the functions of GntR-like transcriptional regulators.

Theoretical Study of the Relationships between Excited State Geometry Changes and Emission Energies of Oxyluciferin

Zhong-wei Li,Chun-gang Min,Ai-min Ren,Jing-fu Guo,John D. Goddard,Ji-kang Feng,Liang Zuo 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.4

In order to find a relationship between firefly luciferases structure and bioluminescence spectra, we focus on excited substrate geometries which may be affected by rigid luciferases. Density functional theory (DFT) and time dependent DFT (TDDFT) were employed. Changes in only six bond lengths of the excited substrate are important in determining the emission spectra. Analysis of these bonds suggests the mechanism whereby luciferases restrict more or less the excited substrate geometries and to produce multicolor bioluminescence.