Helicobacter pylori Chaperone-Like Protein CagT Plays an Essential Role in the Translocation of CagA into Host Cells

( Ding Hong Lei ),( Hao Zeng ),( Lin Ping Huang ),( Yan Dong Dong ),( Yi Jun Duan ),( Xu Hu Mao ),( Gang Guo ),( Quan Ming Zou ) 한국미생물 · 생명공학회 2012 Journal of microbiology and biotechnology Vol.22 No.10

Most of the Helicobacter pylori strains containing the cag pathogenicity island (PAI) have been associated with more severe gastric disease in infected humans. The cag PAI is composed of 27 proteins, and some of the components are required for CagA translocation into host cells as well as induction of proinflammatory cytokines, such as interleukin-8 (IL-8); however, the exact function of most of the components remains unknown or poorly characterized. In this study, we demonstrated that CagT (HP0532), which is an essential structural component of the cag PAI apparatus, plays an important role in the translocation of CagA into host epithelial cells. In addition to being located on the bacterial surface, CagT is also partially localized in the inner membrane, where it acts as a chaperone-like protein and promotes CagA translocation. However, CagT secretion was not detected by immunoprecipitation analysis of cell culture supernatants. Meanwhile, CagT was related to the introduction of IL-8 of the host cell. These results suggest that CagT is expressed on both the inner and outer bacterial membranes, where it serves as a unique type IV secretion system component that is involved in CagA secretion and cag PAI apparatus assembly.

Rapid Detection of Trace 1,4-Dichlorobenzene Using Laser Mass Spectrometry

Lei Ding,Jing Ma,Haiyang Zheng,Li Fang*,Weijun Zhang,Dukhyeon Kim,Hyungki Cha* 대한화학회 2006 Bulletin of the Korean Chemical Society Vol.27 No.9

The 1+1 two-photon Resonant Enhanced Multiphoton Ionization (REMPI) spectra of 1,4-dichlorobenzene was obtained from 240 nm through to 250 nm on a laser mass spectrometer. Special care was taken to build up a heatable sample inlet system suitable for detecting a trace semi-volatile organic compound and reducing the memory effort on the inner wall of the inlet system. The detection limits of 1,4-dichlorobenzene in ppbV/V concentration range at certain wavelengths are presented.

Inverse Source Imaging Methods in Recovering Distributed Brain Sources

Lei Ding,Han Yuan 대한의용생체공학회 2012 Biomedical Engineering Letters (BMEL) Vol.2 No.1

Over the past decades tremendous efforts have been made in developing functional neuroimaging techniques to better understand human brain functions in both normal and diseased states. Towards this goal, it is essential to develop a technique that can noninvasively image human brain activity with high spatial and temporal resolution. Electroencephalography (EEG) and magnetoencephalography (MEG) are important tools for studying the human brain’s large-scale neuronal dynamics, thanks to their millisecond temporal resolution. However, EEG and MEG are limited in providing spatial information concerning the location of active sources in the brain. Localizing the sources of EEG/MEG dynamics can be achieved by the so-called electrophysiological source imaging techniques. Recently, there has been a growing interest in source imaging techniques in recovering distributed brain sources. Such distributed source imaging techniques have been advanced in many aspects, including the forward modeling and the inverse imaging, and have been shown promising in many neuroscience and clinical applications. This paper reviews the basic principles, recent advancements and applications of the distributed source imaging techniques.

Rapid Detection of Trace 1,4-Dichlorobenzene Using Laser Mass Spectrometry

Ding, Lei,Ma, Jing,Zheng, Haiyang,Fang, Li,Zhang, Weijun,Kim, Duk-Hyeon,Cha, Hyung-Ki Korean Chemical Society 2006 Bulletin of the Korean Chemical Society Vol.27 No.9

The 1+1 two-photon Resonant Enhanced Multiphoton Ionization (REMPI) spectra of 1,4-dichlorobenzene was obtained from 240 nm through to 250 nm on a laser mass spectrometer. Special care was taken to build up a heatable sample inlet system suitable for detecting a trace semi-volatile organic compound and reducing the memory effort on the inner wall of the inlet system. The detection limits of 1,4-dichlorobenzene in ppbV/V concentration range at certain wavelengths are presented.

Excessive mechanical strain accelerates intervertebral disc degeneration by disrupting intrinsic circadian rhythm

Ding Sheng-Long,Zhang Tai-Wei,Zhang Qi-Chen,Ding Wang,Li Ze-Fang,Han Guan-Jie,Bai Jin-Song,Li Xi-Lei,Dong Jian,Wang Hui-Ren,Jiang Li-Bo 생화학분자생물학회 2021 Experimental and molecular medicine Vol.53 No.-

Night shift workers with disordered rhythmic mechanical loading are more prone to intervertebral disc degeneration (IDD). Our results showed that circadian rhythm (CR) was dampened in degenerated and aged NP cells. Long-term environmental CR disruption promoted IDD in rats. Excessive mechanical strain disrupted the CR and inhibited the expression of core clock proteins. The inhibitory effect of mechanical loading on the expression of extracellular matrix genes could be reversed by BMAL1 overexpression in NP cells. The Rho/ROCK pathway was demonstrated to mediate the effect of mechanical stimulation on CR. Prolonged mechanical loading for 12 months affected intrinsic CR genes and induced IDD in a model of upright posture in a normal environment. Unexpectedly, mechanical loading further accelerated the IDD in an Light-Dark (LD) cycle-disrupted environment. These results indicated that intrinsic CR disruption might be a mechanism involved in overloading-induced IDD and a potential drug target for night shift workers.

Age-stage, two-sex life tables of the maple poison moth (Lymantria nebulosa Wileman) at different ambient temperatures

Lei Ling,Huang Hui Jing,Yi Jin Yu,Qiu Lin,Ding Wen Bin,He Hua Liang,Yi Tu Yong,Li You Zhi,Xue Jin 한국곤충학회 2021 Entomological Research Vol.51 No.4

The maple poison moth (MPM), Lymantria nebulosa (Wileman), is a Lepidopteran defoliator and one of the most important pests of Liquidambar formosana Hance. The objective of this study was to determine the effects of temperature on the population growth and reproduction of this species. MPM were raised in artificial climate chambers in a laboratory at 21 ± 1°C, 24 ± 1°C, 27 ± 1°C, 30 ± 1°C, 33 ± 1°C and 36 ± 1°C, under a relative humidity (RH) of 70% ± 10% and a 14 L:10D photoperiod, and age-stage, two-sex life tables complied for insects at each temperature. The developmental duration, adult preoviposition period and overall preoviposition period decreased with temperature in a time-dependent manner. The growth curves of the different temperature groups overlapped considerably. The highest larval survival rate (80%) was recorded at 30 ± 1°C. At 36°C only a few eggs hatched and the first instar could not complete the first molt. We consequently regard 36°C as the lethal temperature threshold for this species. Life expectancy decreased with age under all six temperatures. The endogenous growth rate was significantly lower at 21 ± 1°C than at the other temperatures, and was highest in 30 ± 1°C group. The net growth rate of the 30 ± 1°C group was also significantly higher than others. Reproductive parameters were highest at 27 ± 1°C and 30 ± 1°C. Although environmental factors absent from the laboratory environment may limit the generality of our results, they nonetheless provide a theoretical basis for developing integrated control methods for MPM in the wild.

LncRNA H19/miR-29b-3p/PGRN Axis Promoted Epithelial-Mesenchymal Transition of Colorectal Cancer Cells by Acting on Wnt Signaling

Ding, Dayong,Li, Changfeng,Zhao, Tiancheng,Li, Dandan,Yang, Lei,Zhang, Bin Korean Society for Molecular and Cellular Biology 2018 Molecules and cells Vol.41 No.5

This investigation was aimed at working out the combined role of lncRNA H19, miR-29b and Wnt signaling in the development of colorectal cancer (CRC). In the aggregate, 185 CRC tissues and corresponding para-carcinoma tissues were gathered. The human CRC cell lines (i.e. HT29, HCT116, SW480 and SW620) and normal colorectal mucosa cell line (NCM460) were also purchased. Si-H19, si-NC, miR-29b-3p mimics, miR-29b-3p inhibitor, si-PGRN and negative control (NC) were, respectively, transfected into the CRC cells. Luciferase reporter plasmids were prepared to evaluate the transduction activity of $Wnt/{\beta}-catenin$ signaling pathway, and dual-luciferase reporter gene assay was arranged to confirm the targeted relationship between H19 and miR-29b-3p, as well as between miR-29b-3p and PGRN. Finally, the proliferative and invasive capacities of CRC cells were appraised through transwell, MTT and scratch assays. As a result, overexpressed H19 and down-expressed miR-29b-3p displayed close associations with the CRC patients' poor prognosis (P < 0.05). Besides, transfection with si-H19, miR-29b-3p mimic or si-PGRN were correlated with elevated E-cadherin expression, decreased snail and vimentin expressions, as well as less-motivated cell proliferation and cell metastasis (P < 0.05). Moreover, H19 was verified to directly target miR-29b-3p based on the luciferase reporter gene assay (P < 0.05), and miR-29b-3p also bound to PGRN in a direct manner (P < 0.05). Finally, addition of LiCl ($Wnt/{\beta}-catenin$ pathway activator) or XAV93920 ($Wnt/{\beta}-catenin$ pathway inhibitor) would cause remarkably altered E-cadherin, c-Myc, vimentin and snail expressions, as well as significantly changed transcriptional activity of ${\beta}-catenin/Tcf$ reporter plasmid (P < 0.05). In conclusion, the lncRNA H19/miR-29b-3p/PGRN/Wnt axis counted a great deal for seeking appropriate diagnostic biomarkers and treatment targets for CRC.

Tropical forcing of the recent rapid Arctic warming in northeastern Canada and Greenland

Ding, Qinghua,Wallace, John M.,Battisti, David S.,Steig, Eric J.,Gallant, Ailie J. E.,Kim, Hyung-Jin,Geng, Lei Nature Publishing Group, a division of Macmillan P 2014 Nature Vol.509 No.7499

Rapid Arctic warming and sea-ice reduction in the Arctic Ocean are widely attributed to anthropogenic climate change. The Arctic warming exceeds the global average warming because of feedbacks that include sea-ice reduction and other dynamical and radiative feedbacks. We find that the most prominent annual mean surface and tropospheric warming in the Arctic since 1979 has occurred in northeastern Canada and Greenland. In this region, much of the year-to-year temperature variability is associated with the leading mode of large-scale circulation variability in the North Atlantic, namely, the North Atlantic Oscillation. Here we show that the recent warming in this region is strongly associated with a negative trend in the North Atlantic Oscillation, which is a response to anomalous Rossby wave-train activity originating in the tropical Pacific. Atmospheric model experiments forced by prescribed tropical sea surface temperatures simulate the observed circulation changes and associated tropospheric and surface warming over northeastern Canada and Greenland. Experiments from the Coupled Model Intercomparison Project Phase 5 (ref. 16) models with prescribed anthropogenic forcing show no similar circulation changes related to the North Atlantic Oscillation or associated tropospheric warming. This suggests that a substantial portion of recent warming in the northeastern Canada and Greenland sector of the Arctic arises from unforced natural variability.

Variants on ESR1 and their Association with Prostate Cancer Risk: A Meta-analysis

Ding, Xiang,Cui, Feng-Mei,Xu, Song-Tao,Pu, Jin-Xian,Huang, Yu-Hua,Zhang, Jiang-Lei,Wei, Xue-Dong,Hou, Jian-Quan,Yan, Chun-Yin Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Background: Epidemiological studies evaluating the association of two variants rs9340799 and rs2234693 on estrogen receptor 1 (ESR1) with prostate risk have generated inconsistent results. Methods: A meta-analysis was here conducted to systematically evaluate the relationship of these two variants with prostate cancer susceptibility. Results: For rs9340799, heterozygosity of T/C carriers showed a significant increased prostate cancer risk with a pooled odds ratio (OR) of 1.34 (95% CI = 1.06-1.69) while homozygote C/C carriers showed an increased but not statistically significant association with prostate cancer risk (pooled OR = 1.29, 95% CI = 0.94-1.79). Compared to the homozygous TT carriers, the allele C carriers showed a 31% increased risk for prostate cancer (pooled OR = 1.31, 95% CI = 1.06-1.63). No significant association between the rs2234693 and prostate cancer risk was found with the pooled OR of 1.15 (95% CI = 0.97-1.39, T/C and C/C vs. T/T) under the dominant genetic model. Compared to the homozygote T/T carriers, the heterozygous T/C carriers did not show any significantly different risk of prostate cancer (pooled OR = 1.13, 95% CI = 0.94-1.36) and the homozygous C/C carriers also did not show a significant change for prostate cancer risk compared to the wide-type T/T carriers (pooled OR = 1.26, 95% CI = 0.98-1.62). Conclusion: These data suggested that variant rs9340799, but not rs2234693, on ESR1 confers an elevated risk of prostate cancer.

Folate-decorated Polysaccharide-doxorubicin Polymer: Synthesis, Characterization, and Activity in HeLa Cells

Lei Zhang,Lulu Guo,Jingna Ding,Yongming Lu,Yaping Zhang,Yan Chen 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.8

In order to develop the application of the natural polysaccharide lentinan (LNT) and decrease the side effects of doxorubicin, we successfully synthesized a novel folate-modified maleilated lentinan-doxorubicin (FA-M.LNT-DOX) polymer and used it for tumor-targeted drug delivery. The release efficiency and cytotoxicity of the prodrugs were evaluated in vitro. Although DOX release from FA-M.LNT-DOX was quite slow in a neutral buffer, it was particularly fast in an acidic solution with a pH of 5.0. Compared with DOX, FA-M.LNT-DOX showed higher cytotoxicity in HeLa cells and significantly lower cytotoxicity in normal cells. These results suggested that FA-M.LNT-DOX could be considered as a potential drug delivery candidate for folate receptor-positive cancer therapy.