Publications by authors named "Rongyu Li"

22 Publications

  • Page 1 of 1

Circulating humanin is lower in coronary artery disease and is a prognostic biomarker for major cardiac events in humans.

Biochim Biophys Acta Gen Subj 2021 Sep 12:130010. Epub 2021 Sep 12.

The Cardiovascular Center, First Hospital of Jilin University, 71 Xinmin Road, Changchun, Jilin 130021, China. Electronic address:

Background: Humanin is an endogenous mitochondria-derived peptide that plays critical roles in oxidative stress, inflammation and CAD. In this study, we measured the levels of circulating humanin, markers of oxidative stress and inflammation in patients with unstable angina and MI and studied the relationship between these parameters and major adverse cardiac events (MACE).

Methods: A total of 327 subjects were recruited from the inpatient department at First Hospital of Jilin University and divided into 3 groups [control, angina and myocardial infarction (MI)] based on the clinical data and the results of the angiography. Serum humanin and thiobarbituric acid reactive substances (TBARS) were measured at the time of initial admission. The hospitalization data and MACE of all patients were collected.

Results: Circulating humanin levels were lower in the angina group compared to controls [124.22 ± 63.02 vs. 157.77 ± 99.93 pg/ml, p < 0.05] and even lower in MI patients [67.17 ± 24.35 pg/ml, p < 0.05 vs controls] and oxidative stress marker were higher in MI patients compared to the control and angina groups [12.94 ± 4.55 vs. 8.26 ± 1.66 vs. 9.06 ± 2.47 umol/ml, p < 0.05]. Lower circulating humanin levels was an independent risk factor of MI patients. Circulating humanin levels could be used to predict MACE in angina group.

Conclusions: Lower circulating humanin levels was an independent risk factor for CAD, and a potential prognostic marker for mild CAD.

General Significance: Humanin may become a new index for the diagnosis and treatment of CAD.
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http://dx.doi.org/10.1016/j.bbagen.2021.130010DOI Listing
September 2021

Establishment of an Artificial Inoculation Method of Ustilaginoidea virens without Damaging the Rice Panicle Sheaths.

Plant Dis 2021 Sep 13. Epub 2021 Sep 13.

Guiyang, China;

Rice false smut (RFS) is a destructive disease of rice worldwide caused by Ustilaginoidea virens. There is a lack of efficient and stable artificial inoculation method to simulate the natural infection of U. virens, which is an important factor limiting further research on the disease. The purpose of this study was to establish an artificial inoculation method, which can simulate the natural infection process of U. virens without destroying the panicle sheath structure of rice. In this research, rice plants were inoculated by soaking roots at the seedling stage, spraying at the tillering stage, injecting at the booting stage, and again spraying at the flowering stage to determine the appropriate artificial inoculation time. The panicle sheath instillation method and injection inoculation method were compared. The results show that stages 6 to 8 of young panicle differentiation are an important period for U. virens infection. There were no significant differences in the mean rates of infected panicles, mean rates of infected grains, and maximum infected grains per panicle between the two inoculation methods. However, the frequency of RFS ball occurrence at the upper part of the panicles was significantly higher on the spikelets inoculated by the injection method than that of spikelets inoculated by natural infection and panicle sheath instillation. Therefore, panicle sheath instillation method was more similar to the natural infection of U. virens in the field. This research exhibited an innovative artificial inoculation method for identification of U. virens pathogenicity and evaluation of rice resistance against RFS.
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http://dx.doi.org/10.1094/PDIS-12-20-2746-REDOI Listing
September 2021

First Report of Soft Rot on Dendrobium officinale caused by Epicoccum sorghinum in China.

Plant Dis 2021 Sep 7. Epub 2021 Sep 7.

Guizhou University, 71206, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guiyang, Guizhou, China;

In recent years, soft rot is one of the most serious diseases in the production of Dendrobium officinale. In this study, we took the diseased plants of Dendrobium officinale in Guizhou as samples, through Koch's rule and sequence analysis of rDNA internal transcribed spacer (rDNA-ITS), calmodulin (cmdA), the second largest subunit of RNA polymerase Ⅱ (RPB2), elongation factor EF-1 α and β-tubulin (β-Tub), it was determined that the pathogen of Dendrobium officinale soft rot was sorghum accessory cocci. This is our first report on the soft rot of Dendrobium officinale caused by Epicoccum sorghinum in China. The morphological characteristics of the pathogen shown in the study will have a certain reference value for the prevention and control of the soft rot of Dendrobium officinale in the future.
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http://dx.doi.org/10.1094/PDIS-04-21-0866-PDNDOI Listing
September 2021

Naturally produced magnolol can significantly damage the plasma membrane of Rhizoctonia solani.

Pestic Biochem Physiol 2021 Oct 25;178:104942. Epub 2021 Jul 25.

Institute of Crop Protection, Guizhou University, Guiyang 550025, China; The Provincial Key Laboratory for Agricultural Pest Management in Mountainous Region, Guiyang 550025, China; College of Agriculture, Guizhou University, Guiyang 550025, China. Electronic address:

Rice sheath blight is a destructive fungal disease caused by Rhizoctonia solani. To find a safe and green measure, the biological activity of six plant extracts against R. solani was determined by mycelial growth rate method. The results showed that magnolol possessed better antifungal activities against R. solani, with an EC value of 7.47 mg/L. further action mechanism of magnolol against R. solani was carried out. Studies by scanning electron microscopy (SEM) showed that the morphology of R. solani mycelia was deformation and surface folds. Transmission electron microscope (TEM) observation on treated R. solani showed that magnolol could induce cytoplasmic membrane rupture and cytoplasmic membrane even disappeared completely accompanied with cellular debris was covered around this fungal, and the mycelia treated with magnolol showed fluorescence after PI staining. Further study showed that the content of malondialdehyde (MDA) and activity of chitinase, β-1,3-glucanase and relative conductivity of mycelia were increased, while the content of soluble protein and activities of catalase (CAT), polyphenol oxidase (PPO), superoxide dismutase (SOD), succinate dehydrogenase (SDH) and NAD-malate dehydrogenase (NAD-MDH) were significantly decreased. These results indicated that magnolol could significantly damage the plasma membrane of R. solani, and interfere with cell respiratory metabolism, thus inhibiting the growth of mycelium.
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http://dx.doi.org/10.1016/j.pestbp.2021.104942DOI Listing
October 2021

OTULIN allies with LUBAC to govern angiogenesis by editing ALK1 linear polyubiquitin.

Mol Cell 2021 08 21;81(15):3187-3204.e7. Epub 2021 Jun 21.

State Key Laboratory of Proteomics, National Center for Protein Sciences (Beijing), Beijing Institute of Lifeomics, Beijing 100850, China. Electronic address:

OTULIN coordinates with LUBAC to edit linear polyubiquitin chains in embryonic development, autoimmunity, and inflammatory diseases. However, the mechanism by which angiogenesis, especially that of endothelial cells (ECs), is regulated by linear ubiquitination remains unclear. Here, we reveal that constitutive or EC-specific deletion of Otulin resulted in arteriovenous malformations and embryonic lethality. LUBAC conjugates linear ubiquitin chains onto Activin receptor-like kinase 1 (ALK1), which is responsible for angiogenesis defects, inhibiting ALK1 enzyme activity and Smad1/5 activation. Conversely, OTULIN deubiquitinates ALK1 to promote Smad1/5 activation. Consistently, embryonic survival of Otulin-deficient mice was prolonged by BMP9 pretreatment or EC-specific ALK1 (constitutively active) knockin. Moreover, mutant ALK1 from type 2 hereditary hemorrhagic telangiectasia (HHT2) patients exhibited excessive linear ubiquitination and increased HOIP binding. As such, a HOIP inhibitor restricted the excessive angiogenesis of ECs derived from ALK1-expressing HHT2 patients. These results show that OTULIN and LUBAC govern ALK1 activity to balance EC angiogenesis.
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http://dx.doi.org/10.1016/j.molcel.2021.05.031DOI Listing
August 2021

Proteomic analysis reveals that naturally produced citral can significantly disturb physiological and metabolic processes in the rice blast fungus Magnaporthe oryzae.

Pestic Biochem Physiol 2021 Jun 27;175:104835. Epub 2021 Mar 27.

Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China.

Rice blast (Magnaporthe oryzae), a major fungal disease in rice producing areas all over the world as well as in China, seriously affects the safety of rice production. Citral, a mixture of Z/E and trans isomers, is a natural acycloid monoterpene compound with good bacteriostatic effect on rice blast. To further investigate the underlying molecular mechanism, a comparative proteomics analysis was conducted between citral-treated and non-treated M. oryzae spores through two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry. Our analysis identified 1600-1800 proteins from M. oryzae ZB15, of which 147 were differentially expressed in 100 μg/mL citral-treated samples relative to the control group. Among these differentially expressed proteins (DEPs), 40 proteins showed significantly different expression. GO enrichment and NCBI conserved domains database analysis showed that the main groups of the cellular component were cytoplasm (23.33%), and the major molecular function categories were ion binding (31.37%), and the major categories of biological processes included small molecule metabolic process (22.22%) and transport (13.89%). Further analysis found that down-regulated proteins included the tubulin α chain, ATP synthase subunit β and malate dehydrogenase, while the tubulin β, enolase were upregulated. These DEPs could possibly limit the availability of energy required for many cellular processes and result in various physiological adaptions of M. oryzae. This study represents the first proteomic analysis of M. oryzae treated by citral and will help to uncover the mode-of-action of this biologically active compound against M. oryzae. These findings have practical implications with respect to the use of citral for fungal disease control.
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http://dx.doi.org/10.1016/j.pestbp.2021.104835DOI Listing
June 2021

Growth Restriction of via Breakage of Intracellular Organelles Using Crude Extracts of Gallnut and Clove.

Molecules 2021 Mar 17;26(6). Epub 2021 Mar 17.

Institute of Crop Protection, Guizhou University, Guiyang 550025, China.

Plant diseases reduce crop yield and quality, hampering the development of agriculture. Fungicides, which restrict chemical synthesis in fungi, are the strongest controls for plant diseases. However, the harmful effects on the environment due to continued and uncontrolled utilization of fungicides have become a major challenge in recent years. Plant-sourced fungicides are a class of plant antibacterial substances or compounds that induce plant defenses. They can kill or inhibit the growth of target pathogens efficiently with no or low toxicity, they degrade readily, and do not prompt development of resistance, which has led to their widespread use. In this study, the growth inhibition effect of 24 plant-sourced ethanol extracts on rice sprigs was studied. Ethanol extract of gallnuts and cloves inhibited the growth of bacteria by up to 100%. Indoor toxicity measurement results showed that the gallnut and glove constituents inhibition reached 39.23 μg/mL and 18.82 μg/mL, respectively. Extract treated rice sprigs were dry and wrinkled. Gallnut caused intracellular swelling and breakage of mitochondria, disintegration of nuclei, aggregation of protoplasts, and complete degradation of organelles in hyphae and aggregation of cellular contents. Protection of viability reached 46.8% for gallnut and 37.88% for clove in water emulsions of 1000 μg/mL gallnut and clove in the presence of 0.1% Tween 80. The protection by gallnut was significantly stronger than that of clove. The data could inform the choice of plant-sourced fungicides for the comprehensive treatment of rice sprig disease. The studied extract effectively protected rice sprigs and could be a suitable alternative to commercially available chemical fungicides. Further optimized field trials are needed to effectively sterilize rice paddies.
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http://dx.doi.org/10.3390/molecules26061667DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8002394PMC
March 2021

Physicochemical Properties and Bioactivity of a New Guar Gum-Based Film Incorporated with Citral to Brown Planthopper, (Stål) (Hemiptera: Delphacidae).

Molecules 2020 Apr 28;25(9). Epub 2020 Apr 28.

Institute of Plant Protection, College of Agriculture, Guizhou University, Guiyang 550025, Guizhou, China.

The brown planthopper (BPH), Nilaparvata lugens (Stål), is the most notorious rice insect pest. In order to repel BPH effectively while being environmentally friendly, a new film based on guar gum incorporated with citral (GC film) was formulated. A toxicity bioassay of citral and guar gum at different proportions (ratios of 3:1, 2:1, 1:1, 1:2, and 1:3 in /) of GC film-forming emulsion to BPH was performed with the rice stem dipping method. Results showed that the most effective ratio of citral to guar gum was 1:1 with the median lethal concentration (LC) of 4.30 mg/mL, far below the LC of guar gum (GG)/citral individual (141.51 and 44.38 mg/mL, respectively). The mortality of BPH adults and nymphs in the third instar treated with different dilution multiples of GC film-forming emulsion ranged from 46.67% to 82.22% and from 37.78% to 71.11%, respectively. These indicated that GC film-forming emulsion had a direct toxicity on BPH, and the mixture of citral and GG had synergistic interactions. Subsequently, Fourier-transform infrared spectroscopy showed that the incorporation of guar gum with citral was successful and did not result in the formation of new chemical bonds. The GC film exhibited a darker color and rougher surface topography with larger apertures and deeper gullies (Ra = 1.42 nm, Rq = 2.05 nm, and Rmax = 25.40 nm) compared to the guar gum film (GG film) (Ra = 1.00 nm, Rq = 1.33 nm, and Rmax = 16.40 nm), as determined by transmission electron microscopy and atomic force microscopy. The GC film exhibited a 50.4% lower solubility in water (30.30% vs. 15.00%) and 71.3% oxygen permeability (8.26 × 10 vs. 2.37 × 10 cm/m·d·Pa) ( 0.05) but did not demonstrate any significant difference in mechanical properties, such as thickness (39.10 vs. 41.70 mm), tensile strength (41.89 vs. 38.30 N/mm), and elongation at break (1.82% vs. 2.03%) ( 0.05) compared to the GG film. Our findings established a link between physicochemical properties and bioactivity, which can provide useful information on developing and improving GC films and may offer an alternative approach for the control of BPH in the near future.
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http://dx.doi.org/10.3390/molecules25092044DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7249019PMC
April 2020

Enhanced elimination of dimethachlon from soils using a novel strain Brevundimonas naejangsanensis J3.

J Environ Manage 2020 Feb 19;255:109848. Epub 2019 Nov 19.

College of Agricultural Equipment and Engineering, Jiangsu University, Zhenjiang, Jiangsu, 212013, China.

Dimethachlon is a hazardous xenobiotic which poses a potential risk on the ecosystem and human health after foliar spray for mitigating fungal diseases of crops. A novel dimethachlon-degrading strain was isolated and identified as Brevundimonas naejangsanensis J3. Free cells and enzymes of this strain could rapidly eliminate 75 mg/L dimethachlon in liquid medium, especially the latter (>90% of degradation efficiency). Strain J3 completely metabolized dimethachlon by an ideally transformed pathway. Immobilization cells and enzymes exhibited better stability and adaptability for the repeated use, as compared with free cells and enzymes. In laboratory, 68.03 and 65.13%, or 82.67 and 95.41% of dimethachlon were eliminated from non-sterile soils by free or immobilized cells and enzymes within 7 d, respectively. Under the field condition, 95.78 and 98.01% of 20.250 kg a.i./ha dimethachlon wettable powder from soils were degraded by immobilized cells and enzymes in 9 d respectively, which were significant higher than the degradation efficiencies of free cells and enzymes (78.81 and 67.25%). This study highlights immobilized cells and enzymes from strain J3 can be applicable for bioremediating dimethachlon-contaminated soils.
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http://dx.doi.org/10.1016/j.jenvman.2019.109848DOI Listing
February 2020

Effect of pre-discharge cardiopulmonary fitness on outcomes in patients with ST-elevation myocardial infarction after percutaneous coronary intervention.

BMC Cardiovasc Disord 2019 09 6;19(1):210. Epub 2019 Sep 6.

The Cardiovascular Center, First Hospital of Jilin University, 71 Xinmin Road, Changchun, 130021, Jilin, China.

Background: The purpose of this study was to analyze cardiopulmonary fitness in Phase I cardiac rehabilitation on the prognosis of patients with ST-Elevation Myocardial Infarction (STEMI) after percutaneous coronary intervention (PCI).

Methods: The study enrolled a total of 499 STEMI patients treated with PCI between January 2015 and December 2015. Patients were assigned to individualized exercise prescriptions (IEP) group and non-individualized exercise prescriptions (NIEP) group according to whether they accept or refuse individualized exercise prescriptions. We compared the incidence of major cardiovascular events between the two groups. IEP group were further divided into two subgroups based on prognosis status, namely good prognosis (GP) group and poor prognosis (PP) group. Key cardio-pulmonary exercise testing (CPX) variables that may affect the prognosis of patients were identified through comparison of the cardio-respiratory fitness (CRF).

Results: There is no significant difference in the incidence of cardio-genetic death, re-hospitalization, heart failure, stroke, or atrial fibrillation between the IEP and the NIEP group. But the incidence of total major adverse cardiac events (MACE) was significantly lower in the IEP group than in the NIEP group (P = 0.039). The oxygen consumption (VO) at ventilation threshold (VT), minute CO ventilation (E-VCO), margin of minute ventilation carbon dioxide production (△CO) rest partial pressure of end-tidal carbon dioxide(R-PCO), exercise partial pressure of end-tidal carbon dioxide(E-PCO) and margin of partial pressure of end-tidal carbon dioxide(△PCO) were significantly higher in the GP subgroup than in the PP subgroup; and the slope for minute ventilation/carbon dioxide production (V/VCO) was significantly lower in GP subgroup than in PP subgroup (P = 0.010). The VO at VT, V/VCO slope, E-VCO, △CO, R-PCO, E-PCO and margin of partial pressure of end-tidal carbon dioxide CO (△PCO) were predictive of adverse events. The VO at VT was an independent risk factor for cardiovascular disease prognosis.

Conclusions: Individualized exercise prescription of Phase I cardiac rehabilitation reduced the incidence of cardiovascular events in patients with STEMI after PCI. VO at VT is an independent risk factor for cardiovascular disease prognosis, and could be used as an important evaluating indicator for Phase I cardiac rehabilitation.
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http://dx.doi.org/10.1186/s12872-019-1189-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6731574PMC
September 2019

Characterization of drug responses of mini patient-derived xenografts in mice for predicting cancer patient clinical therapeutic response.

Cancer Commun (Lond) 2018 09 26;38(1):60. Epub 2018 Sep 26.

Shanghai LIDE Biotech Co., LTD, Shanghai, 201203, P. R. China.

Background: Patient-derived organoids and xenografts (PDXs) have emerged as powerful models in functional diagnostics with high predictive power for anticancer drug response. However, limitations such as engraftment failure and time-consuming for establishing and expanding PDX models followed by testing drug efficacy, and inability to subject to systemic drug administration for ex vivo organoid culture hinder realistic and fast decision-making in selecting the right therapeutics in the clinic. The present study aimed to develop an advanced PDX model, namely MiniPDX, for rapidly testing drug efficacy to strengthen its value in personalized cancer treatment.

Methods: We developed a rapid in vivo drug sensitivity assay, OncoVee MiniPDX, for screening clinically relevant regimens for cancer. In this model, patient-derived tumor cells were arrayed within hollow fiber capsules, implanted subcutaneously into mice and cultured for 7 days. The cellular activity morphology and pharmacokinetics were systematically evaluated. MiniPDX performance (sensitivity, specificity, positive and negative predictive values) was examined using PDX as the reference. Drug responses were examined by tumor cell growth inhibition rate and tumor growth inhibition rate in PDX models and MiniPDX assays respectively. The results from MiniPDX were also used to evaluate its predictive power for clinical outcomes.

Results: Morphological and histopathological features of tumor cells within the MiniPDX capsules matched those both in PDX models and in original tumors. Drug responses in the PDX tumor graft assays correlated well with those in the corresponding MiniPDX assays using 26 PDX models generated from patients, including 14 gastric cancer, 10 lung cancer and 2 pancreatic cancer. The positive predictive value of MiniPDX was 92%, and the negative predictive value was 81% with a sensitivity of 80% and a specificity of 93%. Through expanding to clinical tumor samples, MiniPDX assay showed potential of wide clinical application.

Conclusions: Fast in vivo MiniPDX assay based on capsule implantation was developed-to assess drug responses of both PDX tumor grafts and clinical cancer specimens. The high correlation between drug responses of paired MiniPDX and PDX tumor graft assay, as well as translational data suggest that MiniPDX assay is an advanced tool for personalized cancer treatment.
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http://dx.doi.org/10.1186/s40880-018-0329-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6158900PMC
September 2018

Contamination of polybrominated diphenyl ethers (PBDEs) in urban mangroves of Southern China.

Sci Total Environ 2019 Jan 20;646:390-399. Epub 2018 Jul 20.

Guangdong Neilingding Futian National Nature Reserve, Shenzhen 518000, China.

Mangroves are threatened due to urban development and human activities in coastal regions. Four urban mangroves in Shenzhen (rapidly developing city of China) were selected according to urban functional zoning, namely, Shajing mangrove (SJM) and Xixiang mangrove (XXM) featured with industry district, Futian mangrove (FTM) and Baguang mangrove (BGM) featured with central business district and ecological preserve. Eight BDE congeners (BDE-28, -47, -99, -100, -153, -154, -183, and -209) in mangrove sediments and leaves were determined. The highest level of BDE-209 in SJM was proximate to areas of point-source discharges of Dongbao River in Pearl River Estuary, China. Total organic carbon (TOC) was influential in BDE-209 accumulations in SJM, XXM, and FTM. Multiple variate analysis implied that PBDEs in SJM, XXM and FTM mainly composed of penta-, octa-, and deca-BDEs, with surface runoff to be the main contamination sources; while BGM was contaminated by penta- and octa-BDEs. Ecological risk of BDE-209 was high in SJM, with medium/negligible risk in the other urban mangroves. The transfers of BDE-209 from sediment to leaf were weak (BGM and FTM), improved (XXM), and restricted (SJM), respectively. This is the first reports of spatial distribution and bioaccumulation of PBDEs in urban mangroves featured with different urban functional zonings. More attention is required to reduce emission of PBDEs into the environment and manage PBDEs contamination in urban mangroves.
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http://dx.doi.org/10.1016/j.scitotenv.2018.07.278DOI Listing
January 2019

Does ammonium nitrogen affect accumulation, subcellular distribution and chemical forms of cadmium in Kandelia obovata?

Ecotoxicol Environ Saf 2018 Oct 14;162:430-437. Epub 2018 Jul 14.

School of Environment and Energy, Shenzhen Graduate School of Peking University, Shenzhen 518055, Guangdong, China.

Heavy metals and nutrients are commonly found in mangrove sediments, but the effect of nutrients on heavy metals in mangrove plants is not clear. A study quantifying the effects of ammonium nitrogen (NH-N) on the accumulation, subcellular distribution and chemical forms of cadmium (Cd) in Kandelia obovata seedlings were conducted. The experiment consisted of four levels of NH-N (0, 10, 50 and 100 mg L) in each of which consisted of four Cd levels (0, 1, 5 and 10 mg L). The results showed that NH-N magnified the Cd toxicity due to reduced plant biomass, especially with 10 mg L Cd and 100 mg L NH-N supply. NH-N, especially at 100 mg L, enhanced the concentration and accumulation of Cd in root but its role on Cd translocation from root to stem and leaf was limited, probably due to low translocation factor. At subcellular level, Cd mainly accumulated in root cell wall but its fractionation depended on Cd levels. Under the stress of 1 and 5 mg L Cd, 50 mg L NH-N supply improved transfer of Cd from root cell wall into cell, and increased pectate and protein integrated forms of intracellular Cd to alleviate Cd toxicity. Under the stress of 10 mg L Cd, NH-N supply promoted the deposition of Cd on root cell wall to restrain its transfer to root cell, which was verified by the reduced levels of pectate and protein integrated forms of Cd in root cell. Thus, NH-N supply improved immobilization of Cd in roots and alleviated Cd toxicity through integration with pectate and protein as well as cell wall combinations in root of K. obovata.
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http://dx.doi.org/10.1016/j.ecoenv.2018.07.031DOI Listing
October 2018

Effects of conversion of mangroves into gei wai ponds on accumulation, speciation and risk of heavy metals in intertidal sediments.

Environ Geochem Health 2019 Feb 23;41(1):159-174. Epub 2018 Jun 23.

Guangdong Neilingding Futian National Nature Reserve, Shenzhen, 518000, China.

Mangroves are often converted into gei wai ponds for aquaculture, but how such conversion affects the accumulation and behavior of heavy metals in sediments is not clear. The present study aims to quantify the concentration and speciation of heavy metals in sediments in different habitats, including gei wai pond, mangrove marsh dominated by Avicennia marina and bare mudflat, in a mangrove nature reserve in South China. The results showed that gei wai pond acidified the sediment and reduced its electronic conductivity and total organic carbon (TOC) when compared to A. marina marsh and mudflat. The concentrations of Cd, Cu, Zn and Pb at all sediment depths in gei wai pond were lower than the other habitats, indicating gei wai pond reduced the fertility and the ability to retain heavy metals in sediment. Gei wai pond sediment also had a lower heavy metal pollution problem according to multiple evaluation methods, including potential ecological risk coefficient, potential ecological risk index, geo-accumulation index, mean PEL quotients, pollution load index, mean ERM quotients and total toxic unit. Heavy metal speciation analysis showed that gei wai pond increased the transfer of the immobilized fraction of Cd and Cr to the mobilized one. According to the acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) analysis, the conversion of mangroves into gei wai pond reduced values of ([SEM] - [AVS])/f, and the role of TOC in alleviating heavy metal toxicity in sediment. This study demonstrated the conversion of mangrove marsh into gei wai pond not only reduced the ecological purification capacity on heavy metal contamination, but also enhanced the transfer of heavy metals from gei wai pond sediment to nearby habitats.
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http://dx.doi.org/10.1007/s10653-018-0130-zDOI Listing
February 2019

Influence of introduced Sonneratia apetala on nutrients and heavy metals in intertidal sediments, South China.

Environ Sci Pollut Res Int 2017 Jan 14;24(3):2914-2927. Epub 2016 Nov 14.

Shenzhen Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Shenzhen Graduate School of Peking University, Shenzhen, 518055, China.

To investigate the influence of Sonneratia apetala on nutrients and heavy metals in intertidal sediments, sediment cores of S. apetala marsh and mudflat in Shenzhen Bay, China were analyzed. The results showed that S. apetala improved sediment nutrient properties due to increased total carbon (TC), total nitrogen (TN), and total sulfur (TS). The levels of heavy metals were higher in S. apetala site than in mudflat, including chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg). In S. apetala site, TC, TN, and TS were not positively correlated with Cr, Ni, As, Cd, and Pb, indicating their less important roles in trapping heavy metals. There were positive correlations among Ni, Cu, Zn, and Cd in both sites, suggesting similar anthropogenic source. Levels of As were higher than the probable effect level at both sites, indicating their toxicological importance. The geo-accumulation index and potential ecological risk index revealed higher metal contaminations in S. apetala site, especially for Cd, Hg, and As. Multivariate analysis implied that S. apetala alter the biogeochemical cycle of Cd and Cr to a certain extent. These findings indicate that S. apetala may improve soil nutrient properties and facilitate heavy metal accumulation in intertidal sediments.
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http://dx.doi.org/10.1007/s11356-016-7885-5DOI Listing
January 2017

Heavy metal contamination and ecological risk in Futian mangrove forest sediment in Shenzhen Bay, South China.

Mar Pollut Bull 2015 Dec 23;101(1):448-456. Epub 2015 Oct 23.

Key Laboratory for Urban Habitat Environment Science and Technology, School of Environment and Energy, Shenzhen Graduate School of Peking University, Shenzhen 518055, China. Electronic address:

Surface sediments in the Futian mangrove forest (South China) were analyzed for heavy metals including cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn). The heavy metal distributions varied greatly in surface sediments, reflecting some sediment heterogeneity. The heavy metal concentrations decreased in the order of Zn>Cr>Pb>Cu>Cd. According to the mean probable effects level quotient, the combination of studied metals had a 21% probability of being toxic. The potential ecological risk index and geo-accumulation index also revealed high metal contamination. Cd was of primary concern due to its higher assessment values and potential for adverse biological effects. Multivariate analysis implied that clay and silt played a significant role in raising the levels of Cr, Cu and Zn. The percentage of mobile heavy metals was relatively higher, without considerable ecological risk to the biota based on the risk assessment code.
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http://dx.doi.org/10.1016/j.marpolbul.2015.09.048DOI Listing
December 2015

Extracellular α-crystallin protects astrocytes from cell death through activation of MAPK, PI3K/Akt signaling pathway and blockade of ROS release from mitochondria.

Brain Res 2015 Sep 18;1620:17-28. Epub 2015 May 18.

Institut für Neurobiochemie (Institut für Inflammation und Neurodegeneration), Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Leipziger Straße 44, Magdeburg 39120, Germany. Electronic address:

α-Crystallin with two isoforms, αA-crystallin (HSPB4) and αB-crystallin (HSPB5), is found in eye lens, spleen, lung, kidney, cornea, skin, but also in brain. Several studies revealed roles of αA/αB-crystallin in regulating cell viability and protection in the central nervous system. We previously demonstrated that α-crystallin serves as an intracellular protectant in astrocytes. Compared to well-studied intracellular functions of α-crystallin, there is limited proof for the role of α-crystallin as extracellular protectant. In order to clarify protective effects of extracellular αA/αB-crystallin, we exposed astrocytes to the toxic agents, staurosporine or C2-ceramide, or serum-starvation in the presence of αA/αB-crystallin. Extracellular αA/αB-crystallin protected astrocytes from staurosporine- and C2-ceramide-induced cell death. In addition, extracellular αB-crystallin/HSPB5 effectively promoted astrocytes viability through phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) and extracellular signal-regulated kinase 1/2 (ERK1/2), p38 mitogen-activated protein kinases (p38) and c-Jun N-terminal kinases (JNK) signaling pathways under serum-deprivation. Furthermore, αB-crystallin/HSPB5 decreases the staurosporine-mediated cleavage of caspase 3 through PI3K/Akt signaling preventing apoptosis of astrocytes. Thus, the current study indicates that extracellular αA/αB-crystallin protects astrocytes exposed to various harmful stimuli. Furthermore, application of αB-crystallin/HSPB5 to isolated rat brain mitochondria inhibits ROS generation induced by complex III inhibition with Antimycin A.
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http://dx.doi.org/10.1016/j.brainres.2015.05.011DOI Listing
September 2015

Specific phosphorylation of αA-crystallin is required for the αA-crystallin-induced protection of astrocytes against staurosporine and C2-ceramide toxicity.

Neurochem Int 2012 May 5;60(6):652-8. Epub 2012 Mar 5.

Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Leipziger Straße 44, 39120 Magdeburg, Germany.

We previously reported that αA-crystallin and protease-activated receptor are involved in protection of astrocytes against C2-ceramide- and staurosporine-induced cell death (Li et al., 2009). Here, we investigated the molecular mechanism of αA-crystallin-mediated cytoprotection. We found that the expression of mutants mimicking specific phosphorylation of αA-crystallin increases the protection of astrocytes. However, the expression of mutants mimicking unphosphorylation of αA-crystallin results in loss of protection. These data revealed that the phosphorylation of αA-crystallin at Ser122 and Ser148 is required for protection. Furthermore, we explored the mechanism of cytoprotection of astrocytes by αA-crystallin. Application of specific inhibitors of p38 and ERK abrogates the protection of astrocytes by over-expression of αA-crystallin. Thus, p38 and ERK contribute to protective processes by αA-crystallin. This is comparable to our previous results which demonstrated that p38 and ERK regulated protease-activated receptor-2 (PAR-2)/αB-crystallin-mediated cytoprotection. Furthermore, we found that PAR-2 activation increases the expression of αA-crystallin. Thus, endogenous αA-crystallin protects astrocytes via mechanisms, which regulate the expression and/or phosphorylation status of αA-crystallin.
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http://dx.doi.org/10.1016/j.neuint.2012.02.031DOI Listing
May 2012

Phosphorylation of Ser45 and Ser59 of αB-crystallin and p38/extracellular regulated kinase activity determine αB-crystallin-mediated protection of rat brain astrocytes from C2-ceramide- and staurosporine-induced cell death.

J Neurochem 2011 Aug 17;118(3):354-64. Epub 2011 Jun 17.

Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Magdeburg, Germany.

We previously demonstrated that αB-crystallin and protease-activated receptor (PAR) are involved in protection of astrocytes against C2-ceramide- and staurosporine-induced cell death [Li et al. (2009) J. Neurochem.110, 1433-1444]. Here, we further investigated the mechanism of cytoprotection by αB-crystallin. Our current data revealed that after down-regulation of αB-crystallin by siRNA, cell death caused by C2-ceramide and staurosporine is increased. Furthermore, we investigated the mechanism of cytoprotection of astrocytes by intracellular αB-crystallin. Application of specific inhibitors of p38 and extracellular regulated kinase (ERK) abrogates the protection of astrocytes by over-expression of αB-crystallin. Thus, p38 and ERK contribute to protective processes by αB-crystallin. To reveal the molecular mechanism of αB-crystallin-mediated cytoprotection, we mimicked phosphorylation or unphosphorylation of αB-crystallin. In these experiments, we found that the phosphorylation of αB-crystallin at Ser45 and Ser59 is required for protection. Ser19 phosphorylation of αB-crystallin does not contribute to protection. Moreover, we detected that PAR-2 activation increases the phosphorylation level of αB-crystallin at Ser59, but does not affect the expression level of αB-crystallin. Thus, endogenous αB-crystallin has protective capacity employing a mechanism, which involves regulation of the phosphorylation status of αB-crystallin and p38 and ERK activity. Moreover, we report that PAR-2 activation evokes the phosphorylation of αB-crystallin to increase astrocytes survival.
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http://dx.doi.org/10.1111/j.1471-4159.2011.07317.xDOI Listing
August 2011

Alpha A-crystallin and alpha B-crystallin, newly identified interaction proteins of protease-activated receptor-2, rescue astrocytes from C2-ceramide- and staurosporine-induced cell death.

J Neurochem 2009 Sep 22;110(5):1433-44. Epub 2009 Jun 22.

Medizinische Fakultät, Institut für Neurobiochemie, Otto-von-Guericke-Universität Magdeburg, Magdeburg 39120, Germany.

Protease-activated receptor-2 (PAR-2) is a G protein-coupled receptor activated by trypsin and other trypsin-like serine proteases. The widely expressed PAR-2 is involved in inflammation response but the physiological/pathological roles of PAR-2 in the nervous system are still uncertain. In the present study, we report novel PAR-2 interaction proteins, alphaA-crystallin and alphaB-crystallin. These 20 kDa proteins have been implicated in neurodegenerative diseases like Alexander's disease, Creutzfeldt-Jacob disease, Alzheimer's disease, and Parkinson's disease. Results from yeast two-hybrid assay using the cytoplasmic C-tail of PAR-2 as bait suggested that alphaA-crystallin interacts with PAR-2. We further demonstrate the in vitro and cellular in vivo interaction of C-tail of PAR-2 as well as of full-length PAR-2 with alphaA(alphaB)-crystallins. We use pull-down, co-immunoprecipitation, and co-localization assays. Analysis of alphaA-crystallin deletion mutants showed that amino acids 120-130 and 136-154 of alphaA-crystallin are required for the interaction with PAR-2. Co-immunoprecipitation experiments ruled out an interaction of alphaA(alphaB)-crystallins with PAR-1, PAR-3, and PAR-4. This demonstrates that alphaA(alphaB)-crystallins are PAR-2-specific interaction proteins. Moreover, we investigated the functional role of PAR-2 and alpha-crystallins in astrocytes. Evidence is presented to show that PAR-2 activation and increased expression of alpha-crystallins reduced C2-ceramide- and staurosporine-induced cell death in astrocytes. Thus, both PAR-2 and alpha-crystallins are involved in cytoprotection in astrocytes.
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http://dx.doi.org/10.1111/j.1471-4159.2009.06226.xDOI Listing
September 2009

Analysis of the factors affecting the accuracy of detection for single base alterations by oligonucleotide microarray.

Exp Mol Med 2005 Apr;37(2):71-7

State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433, P.R. China.

The oligonucleotide microarray, a high-throughput polymorphism detection technology, holds great promise for the characterization of complex genetic variance. To achieve greater sensitivity and specificity for it to be an effective platform technology we present results and discuss some of the factors influencing signal intensities and single-mismatch discrimination in array-based mutation/SNP detection. Probes with a series of concentrations were spotted onto the slide in order to find the optimal concentration with the identifiable satisfying signals and the stable ratios between matched and mismatched probes. It was found that under our experimental conditions, when the initial probe concentration is higher than the maximum immobilization capability of the slide (7.5 microM), the hybridization signal will be saturated and the ratio between matched and mismatched probes will be more stable than at a lower probe concentration. Considering the cost of probes and the systematic stability, a constant spotting concentration of 10 microM was selected. The stability of different types of mismatched oligo-DNA duplexes on the glass surface was also confirmed. The results show that the order of stability of mismatched oligo-DNA duplexes on a glass surface is in general agreement with previous reports conducted using liquid and polyacrylamide gel pads. This suggests that the influence of the mismatched base pair on the stability of the duplex in a solid hybridization system is similar to that in the solution hybridization environment.
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http://dx.doi.org/10.1038/emm.2005.10DOI Listing
April 2005

Systematic comparison of the fidelity of aRNA, mRNA and T-RNA on gene expression profiling using cDNA microarray.

J Biotechnol 2004 Jan;107(1):19-28

State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433, PR China.

In cDNA microarray technology, there are three main reverse transcription based RNA labeling methods, using total RNA (T-RNA), mRNA, and amplified antisense RNA (aRNA), respectively. However, despite the common use of the three types of RNAs, limited data are available regarding their differences and concordances. In this report, we compared the three methods through two sets of self-comparison experiments using the same RNA sample in all cases. Within each method, duplicate hybridizations are highly reproducible with low biases, which are randomly produced. When combining different RNAs within a single array, correlation coefficients between the two channels are rather low, while the discrepancies are persistent. Furthermore, the fidelity of aRNA and mRNA microarrays in the expression profile study shows no significant difference with standard T-RNA based labeling methods. These results suggest that some RNA abundance are selectively changed during aRNA amplification/mRNA purification processes, but it will not affect the gene expression ratio of the two samples if the same type RNA are used. Therefore all three types of RNAs can be used in expression profiling analysis as long as the test and reference samples are generated by identical method within single study.
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http://dx.doi.org/10.1016/j.jbiotec.2003.09.008DOI Listing
January 2004
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