Temporal and spatial impact of Spartina alterniflora invasion on methanogens community in Chongming Island, China

Xue Ping Chen,Jing Sun,Yi Wang,Heng Yang Zhang,Chi Quan He,Xiao Yan Liu,Nai Shun Bu,Xi-En Long 한국미생물학회 2018 The journal of microbiology Vol.56 No.7

Methane production by methanogens in wetland is recognized as a significant contributor to global warming. Spartina alterniflora (S. alterniflora), which is an invasion plant in China’s wetland, was reported to have enormous effects on methane production. But studies on shifts in the methanogen community in response to S. alterniflora invasion at temporal and spatial scales in the initial invasion years are rare. Sediments derived from the invasive species S. alterniflora and the native species Phragmites australis (P. australis) in pairwise sites and an invasion chronosequence patch (4 years) were analyzed to investigate the abundance and community structure of methanogens using quantitative real-time PCR (qPCR) and Denaturing gradient gel electrophoresis (DGGE) cloning of the methyl-coenzyme M reductase A (mcrA) gene. For the pairwise sites, the abundance of methanogens in S. alterniflora soils was lower than that of P. australis soils. For the chronosequence patch, the abundance and diversity of methanogens was highest in the soil subjected to two years invasion, in which we detected some rare groups including Methanocellales and Methanococcales. These results indicated a priming effect at the initial invasion stages of S. alterniflora for microorganisms in the soil, which was also supported by the diverse root exudates. The shifts of methanogen communities after S. alterniflora invasion were due to changes in pH, salinity and sulfate. The results indicate that root exudates from S. alterniflora have a priming effect on methanogens in the initial years after invasion, and the predominate methylotrophic groups (Methanosarcinales) may adapt to the availability of diverse substrates and reflects the potential for high methane production after invasion by S. alterniflora.

The Effect of Transformation on the Virulence of Streptococcus pneumoniae

Xue-Mei Zhang,Yi-Bing Yin,Dan Zhu,Bao-De Chen,Jin-Yong Luo,Yi-Ping Deng,Ming-Fang Liu,Shu-Hui Chen,Jiang-Ping Meng,Kai Lan,Yuan-Shuai Huang,Ge-Fei Kang 한국미생물학회 2005 The journal of microbiology Vol.43 No.4

Although pneumococcus is one of the most frequently encountered opportunistic pathogen in the world, the mechanisms responsible for its infectiveness have not yet been fully understood. In this paper, we have attempted to characterize the effects of pneumococcal transformation on the pathogenesis of the organism. We constructed three transformation-deficient pneumococcal strains, which were designated as Nos. 1d, 2d, and 22d. The construction of these altered strains was achieved via the insertion of the inactivated gene, comE, to strains 1, 2 and 22. We then conducted a comparison between the virulence of the transformation-deficient strains and that of the wild-type strains, via an evaluation of the ability of each strain to adhere to endothelial cells, and also assessed psaA mRNA expression, and the survival of hosts after bacterial challenge. Compared to what was observed with the wild-type strains, our results indicated that the ability of all of the transformation-deficient strains to adhere to the ECV304 cells had been significantly reduced (p < 0.05), the expression of psaA mRNA was reduced significantly (p < 0.05) in strains 2d and 22d, and the median survival time of mice infected with strains 1d and 2d was increased significantly after intraperitoneal bacterial challenge (p < 0.05). The results of our study also clearly indicated that transformation exerts significant effects on the virulence characteristics of S. pneumoniae, although the degree to which this effect is noted appears to depend primarily on the genetic background of the bacteria.

Construction of main effects plans orthogonal through the block factor based on level permutation

Xue-Ping Chen,Jinguan Lin,Xing-Fang Huang 한국통계학회 2015 Journal of the Korean Statistical Society Vol.44 No.4

In this paper, We first demonstrate that the orthogonal property of main effects plans orthogonal through the block factor (Bagchi, 2010) remains unchanged under level permutation. However, level permutation of factors could alter their geometrical structures and statistical properties. Hence uniformity is used to further distinguish main effects plans orthogonal through the block factor (POTB). A modified optimization algorithm is proposed to search uniform or nearly uniform POTBs and many new optimal POTBs with lowerdiscrepancy are obtained.

The Effect of Transformation on the Virulence of Streptococcus pneumoniae

Zhang Xue-Mei,Yin Yi-Bing,Zhu Dan,Chen Bao-De,Luo Jin-Yong,Deng Vi-Ping,Liu Ming-Fang,Chen Shu-Hui,Meng Jiang-Ping,Lan Kai,Huang Yuan-Shuai,Kang Ge-Fei The Microbiological Society of Korea 2005 The journal of microbiology Vol.43 No.4

Although pneumococcus is one of the most frequently encountered opportunistic pathogen in the world, the mechanisms responsible for its infectiveness have not yet been fully understood. In this paper, we have attempted to characterize the effects of pneumococcal transformation on the pathogenesis of the organism. We constructed three transformation-deficient pneumococcal strains, which were designated as Nos. 1d, 2d, and 22d. The construction of these altered strains was achieved via the insertion of the inactivated gene, comE, to strains 1, 2 and 22. We then conducted a comparison between the virulence of the transformation-deficient strains and that of the wild-type strains, via an evaluation of the ability of each strain to adhere to endothelial cells, and also assessed psaA mRNA expression, and the survival of hosts after bacterial challenge. Compared to what was observed with the wild-type strains, our results indicated that the ability of all of the transformation-deficient strains to adhere to the ECV304 cells had been significantly reduced (p < 0.05), the expression of psaA mRNA was reduced significantly (p < 0.05) in strains 2d and 22d, and the median survival time of mice infected with strains Id and 2d was increased significantly after intraperitoneal bacterial challenge (p < 0.05). The results of our study also clearly indicated that transformation exerts significant effects on the virulence characteristics of S. pneumoniae, although the degree to which this effect is noted appears to depend primarily on the genetic background of the bacteria.

The genetic engineering of glycine betaine synthesis in tobacco improves the resistance of the photosynthetic apparatus to drought stress

Wang Gui-Ping,Xue Xiao-Min,Yang Xing-hong,Chen Ru,Han Xue-Ping 한국식물생명공학회 2022 Plant biotechnology reports Vol.16 No.2

In recent years, with the global climate change, the intensity, frequency and duration of drought have increased significantly, which has become the main limiting factor for agricultural development in many areas. Glycine betaine (GB) is an effec- tive stress-resistant substance. In this experiment, the effects of the genetic engineering of GB synthesis on photosynthetic apparatus of tobacco under drought stress were studied using transgenic tobacco (T) accumulating GB and wild-type tobacco (K326, WT). Potted tobaccos were subjected to drought stress (controlled irrigation, 25 °C ± 1 °C, a relative humidity: 75–80%) for 9 days, photosynthetic gas exchange parameters, chlorophyll a fluorescence, structure of chloroplast and thyla- koid membrane, and protein function of thylakoid membrane were examined under different drought stress time (days). The results showed that T tobacco could accumulate GB and the accumulated GB improved the resistance of the photosynthetic apparatus to drought stress. Under drought stress, the damage of chloroplast and thylakoid lamellae in T tobacco was less than that in WT tobacco, the accumulation of GB in T tobacco could maintain the stability of thylakoid membrane, improved the unsaturated fatty acid index (IUFA) of thylakoid membrane lipid, increased the contents of digalactosyl diacylglycerol (DGDG) and phosphatidylglycerol (PG), and decreased the ratio of monogalactosyl diaylglycerol (MGDG) to DGDG. In addition, under drought stress, the accumulation of GB in T tobacco alleviated the photo-inhibition of PSII, and the increase of xanthophyll cycle de-epoxidation may be one of the reasons for the enhancement of PSII function.

Upregulation of STK15 in Esophageal Squamous Cell Carcinomas in a Mongolian Population

Chen, Guang-Lie,Hou, Gai-Ling,Sun, Fei,Jiang, Hong-Li,Xue, Jin-Feng,Li, Xiu-Shen,Xu, En-Hui,Gao, Wei-Shi,Cao, Jian-Ping Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

Background: The STK15 gene located on chromosome 20q13.2 encodes a centrosome-associated kinase critical for regulated chromosome segregation and cytokinesis. Recent studies have demonstrated STK15 to be significantly associated with many tumors, with aberrant expression obseved in many human malignancies. The purpose of this study was to investigate expression of STK15 in esophageal squamous cell carcinomas (ESCCs) in a Mongolian population. Methods: Two non-synonymous single nucleotide polymorphisms in the coding region of STK15, rs2273535 (Phe31Ile) and rs1047972 (Val57Ile) were assessed in 380 ESCC patients and 380 healthy controls. We also detected STK15 mRNA expression in 39 esophageal squamous cell carcinomas and corresponding adjacent tissues by real time PCR. Results: rs2273535 showed a significant association with ESCC in our Mongolian population (rs227353, P allele = 0.0447, OR (95%CI) = 1.259 (1.005~1.578)). Real time PCR analysis of ESCC tissues showed that expression of STK15 mRNA in cancer tissues was higher than in normal tissues (p = 0.013). Conclusions: Our study showed that functional SNPs in the STK15 gene are associated with ESCC in a Mongolian population and up-regulation of STK15 mRNAoccurs in ESCC tumors compared adjacent normal tissues. STK15 may thus have an important role in the prognosis of ESCC and be a potential therapeutic target.

Isolation and Identification of Newly Isolated Antagonistic Streptomyces sp. Strain AP19-2 Producing Chromomycins

Xue-Chang Wu,Wei-Feng Chen,Chao-Dong Qian,Ou Li,Ping Li,Yan-Ping Wen 한국미생물학회 2007 The journal of microbiology Vol.45 No.6

A new antagonistic strain of actinomycete, designated AP19-2, was isolated from the feces of giant pandas inhabiting the Foping National Nature Reserve in China. Cultural characteristic studies strongly suggested that this strain is a member of the genus Streptomyces. The nucleotide sequence of the 16S rRNA gene of strain AP19-2 evidenced profound similarity (97-99%) with other Streptomyces strains. Two pure active molecules were isolated from a fermentation broth of Streptomyces sp. strain AP19-2 via extraction, concentration, silica gel G column chromatography, and HPLC. The chemical structures of the two related compounds (referred to as chromomycin A2 and chromomycin A3) were established on the basis of their Infrared spectra (IR), High Resolution Electrospray Ionization Mass Spectrometry (HR-ESI-MS), and Nuclear Magnetic Resonance (NMR) data, and by comparison with published data.

ORiginal Article : The Expression of Programmed Death-1 in Circulating CD4+ and CD8+ T Cells during Hepatitis B Virus Infection Progression and Its Correlation with Clinical Baseline Characteristics

( Ping Xu ),( Yong Jing Chen ),( Hui Chen ),( Xiao Yan Zhu ),( Hua Feng Song ),( Li Juan Cao ),( Xue Feng Wang ) The Editorial Office of Gut and Liver 2014 Gut and Liver Vol.8 No.2

Background/Aims: Programmed death-1 (PD-1) expression was investigated in CD4+ and CD8+ T cells from hepatitis B virus (HBV)-infected patients at the chronic hepatitis B (CHB) infection, liver cirrhosis (LC), and hepatocellular carcinoma (HCC) stages. Methods: PD-1 expression in circulating CD4+ and CD8+ T cells was detected by flow cytometry. The correla-tions between PD-1 expression and HBV viral load, alanine aminotransaminase (ALT) levels and aspartate aminotrans-ferase (AST) levels were analyzed using GraphPad Prism 5.0. Results: PD-1 expression in CD4+ and CD8+ T cells was significantly increased in both the CHB group and advanced-stage group (LC plus HCC). In the CHB group, PD-1 expres-sion in both CD4+ and CD8+ T cells was positively correlated with the HBV viral load, ALT, and AST levels. However, in the LC plus HCC group, significant correlations between PD-1 expression and the clinical parameters were nearly absent. Conclusions: PD-1 expression in peripheral CD4+ and CD8+ T cells is dynamic, changes with HBV infection progression, and is related to HBV viral load and liver function, especially in CHB. PD-1 expression could be utilized as a potential clini-cal indicator to determine the extent of virus replication and liver injury. (Gut Liver 2014;8:186-195)

Depression and APOEε4 Status in Individuals with Subjective Cognitive Decline: A Meta-Analysis

Yue-ping Huang,Ju-jun Xue,Chao Li,Xi Chen,Hong-juan Fu,Teng Fei,Peng-xiang Bi 대한신경정신의학회 2020 PSYCHIATRY INVESTIGATION Vol.17 No.9

Objective To evaluate the associative role of depression and apolipoprotein E epsilon 4 allele (APOEε4) in subjective cognitive decline(SCD) and its progression to objective cognitive decline. Methods After literature search in electronic databases, studies were selected by following precise eligibility criteria. Meta-analyses were performed to examine the role of APOEε4 and depression in SCD or its progression to mild cognitive impairment (MCI) or dementia. Results APOEε4 positivity was not different between SCD and normal individuals but was significantly higher in individuals with SCD plus than in normal individuals [odds ratio: 2.39 (95% CI: 1.87, 3.05); p<0.00001] and in SCD converters than in non-converters [odds ratio: 5.19 (95% CI: 2.36, 11.42); p<0.00001]. Depression was significantly higher in individuals with SCD [standardized mean difference: 0.63 (0.45, 0.82); p<0.00001] and SCD plus [standardized mean difference: 0.83 (0.43, 1.22); p<0.0001] than in normal individuals. However, depression was not different between SCD and MCI or between SCD converters and non-converters. Age of SCD converters was higher than non-converters [mean difference: 2.95 years (0.58, 5.31)]. Conclusion Whereas APOEε4 positivity was higher in SCD plus and SCD converters, depression was higher in SCD and SCD plus but was not different between SCD and MCI.

Orthotropic Analysis of Steel Deck–Girder–Rib Systems Subjected to Transverse Load

Mu Chen,Jianghong Xue,Ping Li,Fusong Jin 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.3

As one of the advanced modern techniques, orthotropic steel decks are widely used in bridge engineering. Because of its structural complexity, theoretical analysis of mechanical performances of the orthotropic steel bridge deck is very diffi cult. Therefore, in the past 50 years, a series of experiments and fi nite element analysis have been used to obtain the information. A steel deck–girder–rib bridge system subjected to the transverse load is investigated in this paper. The bridge deck is laid on four simply-supported girders at the four edges and is reinforced by ribs in longitudinal direction. The longitudinally stiff ened deck is idealized as an orthotropic plate. The equivalent material properties in the longitudinal and breadth directions of the orthotropic plate are evaluated using micro-mechanics of composite material by treating the ribs as reinforcing fi ber-beams. Governing equations for the deck–girder–rib bridge systems are established and are solved using Ritz method. The analytical solutions are substantiated by comparing with the classic solutions of an isotropic deck with fi xed ends and with the fi nite element predictions. The analytical approach presented in this paper eliminates the very intricate and arduous kinematics study among deck–girder–rib and allows the bridge engineer to fast and convenient estimate the deformation in an orthotropic bridge deck.