Publications by authors named "Zhixin Song"

35 Publications

Correlation between exopolysaccharide biosynthesis and gastrointestinal tolerance of Lactiplantibacillus plantarum.

J Appl Microbiol 2021 Jul 14. Epub 2021 Jul 14.

College of Food Science and Technology, Yangzhou University, Yangzhou, China.

Aim: This study aimed to investigate the correlation between the level of exopolysaccharide (EPS) biosynthesis and gastrointestinal tolerance of 12 Lactiplantibacillus plantarum strains.

Methods And Results: In this study, the EPS production and survival rate of 12 strains of L. plantarum under gastrointestinal stress were determined. Results showed that the EPS biosynthesis level of L. plantarum in semi-defined medium ranged from 9.84 to 26.05 mg/L. The survival rates of all strains in simulated gastric juice at pH 3.0 ranged from 43.52% to 112.73%. Among them, eight strains were higher than 90%, while only one strain was lower than 50%. The survival rates of all strains in simulated intestinal juice ranged from 50.36% to 125.39%, among which eight strains were higher than 80%. The survival rates of all strains under 0.1% bile salt stress ranged from 3.39% to 109.34%, among which four strains were higher than 80% and three strains were lower than 60%. Besides, the survival rates of all strains under 0.5% bile salt stress ranged from 0.42% to 95.34%. The results indicated that the 12 L. plantarum strains had good tolerance to simulated gastric juice at pH 3.0, simulated intestinal juice and 0.1% bile salt. Notably, it was observed that the survival rates of L. plantarum strains under simulated gastric juice at pH 3.0 and simulated intestinal juice were significantly positively correlated with EPS biosynthesis (p < 0.01).

Conclusion: The yield of EPS of L. plantarum was related to simulated gastric juice and simulated intestinal juice environment.

Significance And Impact Of Study: It was speculated that the production of EPS may be one of the strategies for L. plantarum to adapt to the part of gastrointestinal environment. In the future, we could analyse the protection mechanism of EPS from the gene level.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jam.15213DOI Listing
July 2021

Circulating Prokineticin 2 Levels Are Increased in Children with Obesity and Correlated with Insulin Resistance.

Int J Endocrinol 2021 4;2021:6630102. Epub 2021 Apr 4.

Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing Key Laboratory of Child Health and Nutrition, Chongqing 400014, China.

Objective: Prokineticin 2 (PK2) has been shown to regulate food intake, fat production, and the inflammation process, which play vital roles in the pathogenesis of obesity. The first aim of this study was to investigate serum PK2 levels in children with obesity and normal-weight children. The second aim was to compare the levels of PK2 between children with obesity, with and without nonalcoholic fatty liver disease (NAFLD).

Methods: Seventy normal-weight children and 91 children with obesity (22 with NAFLD) were recruited. Circulating PK2, IL-6, and TNF- were measured by enzyme-linked immunosorbent assays. Anthropometric and biochemical measurements related to adiposity, lipid profile, and insulin resistance were examined for all participants.

Results: Serum PK2 was significantly higher in children with obesity than in the normal-weight controls. Circulating PK2 levels were not different between the patients with and without NAFLD. Circulating PK2 was positively correlated with BMI, BMI z-score, insulin, glucose, HOMA-IR, total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, and gamma-glutamyl transpeptidase. Binary logistic regression revealed that the odds ratios for obesity were significantly elevated with increasing PK2.

Conclusions: PK2 was strongly associated with obesity, and it may also be related to metabolic disorders and insulin resistance. This trial is registered with ChiCTR2000038838.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2021/6630102DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8041561PMC
April 2021

Spatial and temporal distribution of Mo in the overlying water of a reservoir downstream from mining area.

J Environ Sci (China) 2021 Apr 10;102:256-262. Epub 2020 Oct 10.

School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450011, China.

This study aimed to evaluate the spatial and temporal variations of molybdenum (Mo) in the downstream water body of a Mo mine during three hydrologic periods (wet, dry and medium seasons). The physical properties in Luhun Reservoir reflected seasonal variations in different hydrological periods. The redox potential (ORP) and dissolved oxygen (DO) increased in the dry season. The concomitant decrease in temperature (T), conductivity (COND) and total dissolved solids (TDS) were lowest in the wet season. The pH value did not change significantly during the three hydrologic periods. The distribution of Mo in the dry season was high in upstream and low in downstream areas, which was significantly different from that of the wet and medium seasons. The total Mo concentration in wet (150.1 µg/L) and medium season (148.2 µg/L) was higher than that in the dry season, but the TDS (288.3 mg/L) and the percentage dissolved Mo (81.3%) in overlying water was lowest in the wet season. There was no significant relationship between the dissolved Mo and the total Mo with TDS. In the dry season, the mean total Mo concentration was 116.3 µg/L, which was higher than the standard limit value (70 µg/L) for drinking water (US EPA-United States Environmental Protection Agency recommended value 40 µg/L). Non-point source pollution is the main characteristic of mining area pollution, which was closely related to rainfall. Thus, the Luhun Reservoir contains substantial Mo pollution, which was a significant concern given that it is used as a source of drinking and irrigation water.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jes.2020.09.033DOI Listing
April 2021

Molybdenum contamination dispersion from mining site to a reservoir.

Ecotoxicol Environ Saf 2021 Jan 13;208:111631. Epub 2020 Nov 13.

School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450011, China.

This study was conducted to assess heavy metals in the overlying water and sediments of Luhun Reservoir, Henan Province, China, which is positioned downstream from a molybdenum (Mo) mining area. The pollution indexes indicated that deposition of all metals may have been affected by the mining area. The single element pollution factor (P) of Mo was the highest among all heavy metals, with a mean value of 2.05. However, the sediments were subject to long-term accumulation of metals, particularly Mo, Cd, Pb, and Zn, which originated from anthropogenic sources. The mean individual element potential ecological risk index values for Cd were above 385, while the mean value comprehensive potential ecological risk index was 465, which indicates a high ecological risk. Moreover, the enriched heavy metals had different spatial distributions in the Luhun Reservoir sediments. Finally, Pearson correlation analysis indicated that the Pb was mainly affected by different anthropogenic sources and had no relationship with other metals, which suggests that the influence of mining area on heavy metal concentrations in the reservoir is difficult to disentangle.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ecoenv.2020.111631DOI Listing
January 2021

Chemical fractionation and risk assessment of surface sediments in Luhun Reservoir, Luoyang city, China.

Environ Sci Pollut Res Int 2020 Oct 26;27(28):35319-35329. Epub 2020 Jun 26.

School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450046, People's Republic of China.

To understand the potential risks of heavy metals, including their bioavailability and toxicity, 15 surface sediment samples were collected from Luhun Reservoir in Luoyang city, China. Total concentrations and chemical fractions of Cd, Cr, Cu, Ni, Pb, and Zn were analyzed. Various rating methods were used to evaluate the degree, risk, and toxicity of the heavy metal pollution. Results showed that Cd and Pb were preferentially associated with exchangeable (55.77-69.76%) and reducible (53.54-69.43%) fractions, respectively, and therefore exhibited high potential availability. Cr (57.14-86.56%) and Ni (32.21-72.77%) occurred primarily in the residual fraction. Metal concentrations in the effective fraction of the sediment decreased in the order: Cd (96.32%) > Pb (91.61%) > Cu (64.54%) > Zn (57.23%) > Ni (41.51%) > Cr (21.68%). Risk assessment indicated that the risk for Cd is extremely high (62.96%); Cu, Pb, and Zn are ranked as medium risk. Based on the potential ecological risk index, these metals (especially Cd) showed higher potential risk near the dam region. Toxic unit values (2.89-6.05) in more than 60% of sediment sites exceeded a value of 4, and Pb had a relatively higher contribution (1.06-2.65). Cd and Pb are the main contaminants in sediments of Luhun Reservoir and should be paid more attention in the future.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-020-09512-7DOI Listing
October 2020

Determining cadmium bioavailability in sediment profiles using diffusive gradients in thin films.

J Environ Sci (China) 2020 May 10;91:160-167. Epub 2020 Feb 10.

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address:

Cadmium (Cd) uptake by plants or benthic organisms largely depends on its bioavailability in sediments, so it is necessary to understand Cd bioavailability for determining its ecological risks in riverine sediments. Pore water is easily disturbed during sample collection, indicating that there was a shortage of traditional methods for investigating Cd bioavailability. Here, sediment cores were collected from rivers, after which sequential extraction and diffusive gradients in thin films (DGT) method were employed to determine Cd potential bioavailability in the sediments and pore water. We found that Cd concentrations measured by DGT were lower than that in pore water profiles, and Cd distribution in various fractions changed remarkably. Pearson correlation analysis showed significant positive correlations between Cd concentrations measured by DGT and total Cd concentrations (r = 0.76), exchangeable and weak acid soluble fraction (r = 0.68), ferromanganese fraction (r = 0.72) and bound organic matter or oxidizable fraction (r = 0.54). However, the correlation was relatively low between Cd concentrations measured by DGT and that in pore water profiles (r = 0.26). These results demonstrated that DGT method could provide more accurate information of Cd bioavailability in sediment profiles than traditional methods.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jes.2020.01.025DOI Listing
May 2020

Synergistic induction of CCL5, CXCL9 and CXCL10 by IFN-γ and NLRs ligands on human fibroblast-like synoviocytes-A potential immunopathological mechanism for joint inflammation in rheumatoid arthritis.

Int Immunopharmacol 2020 Mar 6;82:106356. Epub 2020 Mar 6.

Department of Clinical Laboratory; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders; Children's Hospital of Chongqing Medical University, Chongqing, PR China; Chongqing Key Laboratory of Pediatrics, Chongqing, China. Electronic address:

Interferon-γ (IFN-γ) is traditionally regarded as a proinflammatory cytokine by virtue of its strong macrophage activating potential and its association with Th1 driven immune responses. NOD1 and NOD2 are cytoplasmic receptors that can initiate the initial immune response by sensing bacterial components or danger signals. In this study, we investigated the immunopathological roles of IFN-γ and NOD1, 2 ligands iE-DAP/MDP on the activation of fibroblast-like synoviocytes (FLS) in RA. FLS constitutively express functional NOD1 and NOD2, and the gene and protein expression of NOD1 and NOD2 could be enhanced by the treatment with IFN-γ. The synergistic effect was observed in the combined treatment of IFN-γ and NOD1 ligand iE-DAP or NOD2 ligand MDP on the release of CCL5, CXCL9 and CXCL10 from FLS, and its effect was in a dose-dependent manner. The co-stimulation which IFN-γ combined with iE-DAP/MDP could abolish the inhibition of CXCL8 level by IFN-γ alone. Further investigations showed that synergistic effects on the production of CCL5, CXCL9 and CXCL10 in FLS stimulated by IFN-γ and iE-DAP/MDP were differentially regulated by intracellular activation of NF-κB, p38MAPK and ERK pathways. In conclusion, our data confirmed the inflammatory effect of IFN-γ and iE-DAP/MDP on human FLS for the first time and therefore provided a new insight into the IFN-γ combined with NOD1 or NOD2 activated immunopathological mechanisms mediated by distinct intracellular signal transduction in joint inflammation of RA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.intimp.2020.106356DOI Listing
March 2020

Progranulin as a novel biomarker in diagnosis of early-onset neonatal sepsis.

Cytokine 2020 04 23;128:155000. Epub 2020 Jan 23.

Department of Clinical Laboratory, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, PR China; Chongqing Key Laboratory of Pediatrics. Chongqing, China. Electronic address:

Background: Infections are leading causes of morbidity and mortality in neonates and may also have severe long-term consequences. As early diagnosis of neonatal sepsis improves prognosis, identification of new or complementary biomarkers is of great importance. In this study, we have evaluated the diagnostic value of progranulin (PGRN) in early-onset neonatal sepsis (EOS) and compare its effectiveness with other commonly used biomarkers, such as procalcitonin (PCT) and C-reactive protein (CRP).

Methods: A total of 121 infants with gestational age of >34 weeks admitted with suspected EOS were included in this study. Before initiating therapy, blood samples for whole blood count, CRP, PCT and PGRN were obtained from all neonates. Receiver-operating characteristic (ROC) curve and multivariate logistic regression analyses were performed.

Results: Serum PGRN level of infected group was significantly higher than uninfected group (median 47.72 vs. 37.86 ng/ml, respectively; Mann-Whitney p < 0.0001). The ROC area under the curve (AUC) was 0.786 [95% confidence interval (CI) 0.706-0.867; p < 0.0001] for PGRN, 0.699 (95% CI 0.601-0.797; p = 0.0001) for age adjusted PCT, and 0.673 (95% CI 0.573-0.773; p = 0.0007) for CRP. With a cut-off value of 37.89 ng/ml, the diagnostic sensitivity and negative predictive value of PGRN were 94.34% and 91.7%, respectively. PGRN could significantly predict EOS independently of PCT (p < 0.0001), and the combined use of PGRN and PCT could significantly improve diagnostic performance for EOS (0.806; 95% CI 0.73-0.88; p < 0.0001), with a specificity of 89.06% and a positive predictive value of 81.10%.

Conclusions: PGRN may be used as a promising biomarker for the diagnosis of EOS, and the combined use of PGRN and PCT could improve the diagnosis of sepsis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cyto.2020.155000DOI Listing
April 2020

Progranulin Mediates Proinflammatory Responses in Systemic Lupus Erythematosus: Implications for the Pathogenesis of Systemic Lupus Erythematosus.

J Interferon Cytokine Res 2020 01 4;40(1):33-42. Epub 2019 Dec 4.

Key Laboratory of Diagnostic Medicine Designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.

Systemic lupus erythematosus (SLE) is an autoimmune disease caused by the disorders of immune regulation but its pathogenesis is poorly understood. Progranulin (PGRN) is an immunomodulatory protein that is upregulated in SLE patients. However, the factors involved in regulating the pathogenesis of SLE by PGRN are largely unknown. We sought to investigate the role and molecular mechanisms of PGRN in SLE to develop a novel therapeutic target. We used an animal model of SLE that was induced in PGRN-deficient and normal wild type (WT) mice using pristane. PGRN concentrations were measured in SLE and the impact of PGRN deficiency was examined by measuring tissue injury and immune responses of T cells (Th1, Th2, Th17, and Treg) and B cells. SLE patients and mice showed elevated PGRN levels. Compared with WT SLE mice, inflammatory cell infiltration, tissue edema, and necrosis were alleviated in PGRN SLE mice and the levels of serum chemistry markers of tissue damage and the presence of anti-double-stranded DNA and anti-ribosomal protein P0 antibodies were all significantly decreased. We further discovered that PGRN deficiency could disturb the immune responses of T cell (Th1, Th2, Th17, and Treg) and B cell responses, leading to the decrease of inflammatory cytokines including interferon-γ and interleukin-17A and increased levels of regulatory B cells. PGRN plays a proinflammatory role in the development of SLE partially through promoting the production of autoantibodies and enhancing Th1 and Th17 cell responses. This may provide new therapeutic options for patients with SLE.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1089/jir.2019.0047DOI Listing
January 2020

Assessment of Apoptosis Inhibitor of Macrophage/CD5L as a Biomarker to Predict Mortality in the Critically Ill With Sepsis.

Chest 2019 10 30;156(4):696-705. Epub 2019 May 30.

Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing. Electronic address:

Background: To determine the utility of apoptosis inhibitor of macrophage (AIM)/CD5L as a potentially novel biomarker of morbidity and mortality in patients with sepsis who are critically ill.

Methods: There were 150 adult patients with sepsis studied. Serum AIM levels on day of ICU admission were determined and compared with survival status and organ dysfunction. For validation, 60 adult patients with sepsis from another medical center were studied. Furthermore, the role of AIM as an outcome predictor in 51 pediatric patients with sepsis was investigated.

Results: In the derivation cohort of adult patients, patients with sepsis had markedly increased admission levels of serum AIM compared with ICU control subjects and healthy control subjects. Higher serum AIM levels at admission were significantly associated with higher Sequential (sepsis-related) Organ Failure Assessment (SOFA) scores. On day of ICU admission, the area under the receiver operating characteristic curve (AUC) for AIM level association with 28-day mortality was 0.86, higher than the AUC for SOFA (0.77), procalcitonin (0.73), lactate (0.67), IL-27 (0.65), and C-reactive protein (0.55). Patients with sepsis with higher admission levels of AIM (> 543.66 ng/mL) had significantly increased 28-day mortality compared with those with lower AIM levels (≤ 543.66 ng/mL). The association between admission levels of AIM and 28-day mortality was confirmed in the validation cohort of adult patients. In another cohort of pediatric patients with sepsis, the AUC for AIM level association with 28-day mortality was 0.82.

Conclusions: Circulating AIM levels at admission were markedly increased in patients with sepsis, which can serve as a novel prognostic biomarker for predicting mortality.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chest.2019.04.134DOI Listing
October 2019

Interleukin-34 Ameliorates Survival and Bacterial Clearance in Polymicrobial Sepsis.

Crit Care Med 2018 06;46(6):e584-e590

Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.

Objectives: Sepsis is a devastating condition with a high mortality rate and limited treatments. Sepsis is characterized by a failed host immune response to contain the infection, resulting in organ dysfunction. Interleukin-34 is new cytokine involved in infection and immunity. Whether interleukin-34 is beneficial or deleterious to sepsis and the underlying mechanisms remains unknown.

Design: Prospective randomized animal investigation and in vitro studies.

Setting: Research laboratory at a university hospital.

Subjects: Wild-type C57BL/6 mice were used for in vivo studies, and septic human patients and healthy human subjects were used to obtain blood for in vitro studies.

Interventions: Interleukin-34 concentrations were measured in human sepsis patients and healthy individuals. The effects of interleukin-34 administration on survival, bacterial burden, organ injury, and inflammatory response were assessed in a murine model of cecal ligation and puncture-induced polymicrobial sepsis.

Measurements And Main Results: Interleukin-34 levels were significantly elevated in human sepsis and cecal ligation and puncture-induced experimental sepsis. Interleukin-34 administration improved survival and bacterial clearance, although suppressed vascular leakage and organ injury after cecal ligation and puncture-induced polymicrobial sepsis. Neutralization of interleukin-34 increased mortality rate and decreased bacterial clearance in septic mice. An increased neutrophil and macrophage influx were developed in interleukin-34-treated mice at the site of infection, accompanied by elevated production of neutrophil chemokine chemokine (C-X-C motif) ligand 1 and macrophage chemokine C-C motif chemokine ligand 2 in the peritoneal cavity. Depletion of neutrophils or macrophages reversed interleukin-34-mediated protection against polymicrobial sepsis.

Conclusions: We reported for the first time a potential therapeutic role for interleukin-34 in sepsis and suggested that interleukin-34 is a novel target for the development of therapeutic agents against sepsis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/CCM.0000000000003017DOI Listing
June 2018

Evaluating the diffusive gradients in thin films technique for the prediction of metal bioaccumulation in plants grown in river sediments.

J Hazard Mater 2018 Feb 25;344:360-368. Epub 2017 Oct 25.

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Science, Beijing 100049, China. Electronic address:

The diffusive gradients in thin films (DGT) technique is a useful tool for assessing metal bioavailability in sediments. However, the DGT technique has not been used to predict metal bioaccumulation in plants grown in sediments in river systems. In this study, the DGT technique was evaluated for predicting metal bioaccumulation in Phragmites australis growing in contaminated sediments. In sediments with high levels of contamination, release of DGT-labile Cr, Zn, Cu, and Cd occurred, which resulted in high bioaccumulation of these metals in P. australis. Bioaccumulation of Cr, Cu, Zn, and Cd was strongly correlated with the metal concentrations in the sediments measured by the DGT technique. By contrast, the correlation between sediment content and bioaccumulation for As was weak. There were significant negative correlations between the content of Ni in the plant tissues and the contents of the other metals. Overall, the DGT technique provided predictions of metal bioaccumulation similar to those obtained using total metal measurements in multiple polluted sediment samples. Therefore, DGT analysis could be used for assessing heavy metal bioavailability, and metal bioaccumulation in P. australis was not all significantly correlated with the bioavailability concentrations of metals in river sediments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2017.10.049DOI Listing
February 2018

Assessment of potential bioavailability of heavy metals in the sediments of land-freshwater interfaces by diffusive gradients in thin films.

Chemosphere 2018 Jan 9;191:218-225. Epub 2017 Oct 9.

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Science, Beijing 100049, China. Electronic address:

It is important to understand the potential bioavailability of heavy metals in the sediments of land-freshwater interfaces (between terrestrial and aquatic ecosystems). Therefore, we evaluated the pollution of Cr, Ni, Cu, Zn, As, and Cd in land-freshwater interface sediments/soils according to total concentrations, and used sequential extraction method to measure different fractions of Cd. Then, the diffusive gradients in thin films (DGT) technique was employed to study the potential bioavailability of metals. Results showed that the concentrations of exchangeable and weak acid soluble fraction and oxidizable fraction were higher in ecotone area, and the values of reducible fraction and residual fraction were higher in deep water area. There existed significant positive correlations between [Cd]-DGT (concentration of Cd measured by DGT) and EXC-Cd (exchangeable and weak acid soluble fraction of Cd) (r = 0.65), but the significant negative correlation was found between [Cd]-DGT and RES-Cd (Residual fraction of Cd) (r = 0.52). DGT technique is a feasible method to measure potential bioavailability of heavy metals for risk assessment in the sediments/soils of land-freshwater interfaces.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2017.10.048DOI Listing
January 2018

A scheme to scientifically and accurately assess cadmium pollution of river sediments, through consideration of bioavailability when assessing ecological risk.

Chemosphere 2017 Oct 14;185:602-609. Epub 2017 Jul 14.

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Science, Beijing 100049, China. Electronic address:

Evaluating heavy metal pollution status and ecological risk in river sediments is a complex task, requiring consideration of contaminant pollution levels, as well as effects of biological processes within the river system. There are currently no simple or low-cost approaches to heavy metal assessment in river sediments. Here, we introduce a system of assessment for pollution status of heavy metals in river sediments, using measurements of Cd in the Shaocun River sediments as a case study. This system can be used to identify high-risk zones of the river that should be given more attention. First, we evaluated the pollution status of Cd in the river sediments based on their total Cd content, and calculated a risk assessment, using local geochemical background values at various sites along the river. Using both acetic acid and ethylenediaminetetraacetic acid to extracted the fractions of Cd in sediments, and used DGT to evaluate the bioavailability of Cd. Thus, DGT provided a measure of potentially bioavailable concentrations of Cd concentrations in the sediments. Last, we measured Cd contents in plant tissue collected at the same site to compare with our other measures. A Pearson's correlation analysis showed that Cd-Plant correlated significantly with Cd-HAc, (r = 0.788, P < 0.01), Cd-EDTA (r = 0.925, P < 0.01), Cd-DGT (r = 0.976, P < 0.01), and Cd-Total (r = 0.635, P < 0.05). We demonstrate that this system of assessment is a useful means of assessing heavy metal pollution status and ecological risk in river sediments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemosphere.2017.07.059DOI Listing
October 2017

Will heavy metals in the soils of newly submerged areas threaten the water quality of Danjiangkou Reservoir, China?

Ecotoxicol Environ Saf 2017 Oct 22;144:380-386. Epub 2017 Jun 22.

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Science, Beijing 100049, China.

Soil heavy metal contents were measured in newly submerged areas of the Danjiangkou Reservoir, China. We aimed to determine the heavy metal distribution in this area and the associated ecological risk. Most of these heavy metal contents (except Pb and Mn) suggest enrichment compared with the background values of soils from Henan Province, especially As and Cd with mean geo-accumulation index (I) values of 0.84 and 0.54. The spatial analysis results indicated that the highest heavy metal contents were distributed in the arable soils above 160m elevation, whereas low heavy metal contents were observed under other land-use types above 160m elevation. According to I and EF values, Cd was the major heavy metal contaminant in the newly submerged area, Cr, Pb and Mn mainly originated from natural geochemical sources. In contrast, Ni, Cd, As, Cu, and Zn mainly originated from anthropogenic sources. Evaluation using the potential ecological risk (PER) method indicated that PER of individual elements were low in the studied soils, and the comprehensive PER index was at a moderate level, indicating heavy metals in the soils of newly submerged areas may not threaten the water quality of Danjiangkou Reservoir, especially in winter.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ecoenv.2017.06.050DOI Listing
October 2017

Contribution of Progranulin to Protective Lung Immunity During Bacterial Pneumonia.

J Infect Dis 2017 06;215(11):1764-1773

Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University.

Background: Progranulin (PGRN) is an important immunomodulatory factor in a variety of inflammatory diseases. However, its role in pulmonary immunity against bacterial infection remains unknown.

Methods: Pneumonia was induced in PGRN-deficient and normal wild-type mice using Pseudomonas aeruginosa or Staphylococcus aureus, and we assessed the effects of PGRN on survival, bacterial burden, cytokine and chemokine production, and pulmonary leukocyte recruitment after bacterial pneumonia.

Results: Patients with community-acquired pneumonia displayed elevated PGRN levels. Likewise, mice with Gram-negative and Gram-positive pneumonia had increased PGRN production in the lung and circulation. Progranulin deficiency led to increased bacterial growth and dissemination accompanied by enhanced lung injury and mortality in bacterial pneumonia, which was associated with impaired recruitment of macrophages and neutrophils in the lung. The reduced number of pulmonary macrophages and neutrophils observed in PGRN-deficient mice was related to a reduction of CCL2 and CXCL1 in the lungs after bacterial pneumonia. Importantly, therapeutic administration of PGRN improved mortality in severe bacterial pneumonia.

Conclusions: This study supports a novel role for PGRN in pulmonary immunity and suggests that treatment with PGRN may be a viable therapy for bacterial pneumonia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/infdis/jix197DOI Listing
June 2017

Purified Streptococcus pneumoniae Endopeptidase O (PepO) Enhances Particle Uptake by Macrophages in a Toll-Like Receptor 2- and miR-155-Dependent Manner.

Infect Immun 2017 04 23;85(4). Epub 2017 Mar 23.

Department of Laboratory Medicine, Key Laboratory of Diagnostic Medicine (Ministry of Education), Chongqing Medical University, Chongqing, People's Republic of China

Insights into the host-microbial virulence factor interaction, especially the immune signaling mechanisms, could provide novel prevention and treatment options for pneumococcal diseases. endopeptidase O (PepO) is a newly discovered and ubiquitously expressed pneumococcal virulence protein. A PepO-mutant strain showed impaired adherence to and invasion of host cells compared with the isogenic wild-type strain. It is still unknown whether PepO is involved in the host defense response to pneumococcal infection. Here, we demonstrated that PepO could enhance phagocytosis of and by peritoneal exudate macrophages (PEMs). Further studies showed that PepO stimulation upregulated the expression of microRNA-155 (miR-155) in PEMs in a time- and dose-dependent manner. PepO-induced enhanced phagocytosis was decreased in cells transfected with an inhibitor of miR-155, while it was increased in cells transfected with a mimic of miR-155. We also revealed that PepO-induced upregulation of miR-155 in PEMs was mediated by Toll-like receptor 2 (TLR2)-NF-κB signaling and that the increased expression of miR-155 downregulated expression of SHIP1. Taken together, these results indicate that PepO induces upregulation of miR-155 in PEMs, contributing to enhanced phagocytosis and host defense response to pneumococci and .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/IAI.01012-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5364319PMC
April 2017

Effect of 5-HT2A Receptor Polymorphisms, Work Stressors, and Social Support on Job Strain among Petroleum Workers in Xinjiang, China.

Int J Environ Res Public Health 2016 12 19;13(12). Epub 2016 Dec 19.

Department of Occupational and Environmental Health, College of Public Health, Xinjiang Medical University, Urumqi 830011, Xinjiang, China.

Previous studies have shown that work stressors and social support influence job strain. However, few studies have examined the impact of individual differences on job strain. In Xinjiang, there are a large number of petroleum workers in arid deserts. The present study investigated the effects of work stressors, social support, and 5-hydroxytryptamine receptor (5-HTR2A) genotype on the etiology of job strain among petroleum workers in Xinjiang. A cross-sectional study was carried out between January and August 2013. A total of 700 workers were selected by a three-stage stratified sampling method. 5-HTR2A genotypes were determined with the SNaPshot single nucleotide polymorphism assay. Work stressors and job strain were evaluated with the Occupational Stress Inventory-Revised questionnaire. Social support was assessed with the Chinese Social Support Rating Scale. Work overload and responsibility were significantly associated with job strain. Low social support was associated with severe vocational and interpersonal strain. High social support was a protective factor against job strain (odds ratio (OR) = 0.32, 95% confidence interval (CI): 0.14-0.76). The CC genotype of rs6313 and the AA genotype of rs2070040 were linked to severe vocational strain. Ordinal logistic regression analysis revealed that the CC genotype of rs6313 was linked to higher risk of job strain than the TT genotype (OR = 1.88, 95% CI: 1.10-3.23). These data provide evidence that work stressors, low social support, and 5-HTR2A gene polymorphism contributes to the risk of job strain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph13121258DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5201399PMC
December 2016

Interleukin 36α Attenuates Sepsis by Enhancing Antibacterial Functions of Macrophages.

J Infect Dis 2017 01;215(2):321-332

Department of Laboratory Medicine.

Background: Sepsis is newly defined as life-threatening organ dysfunction caused by a dysregulated host response to infection with a high mortality rate and limited effective treatments. The role of interleukin 36α (IL-36α) in host response during sepsis remains unknown.

Methods: An experimental sepsis model of cecal ligation and puncture was established to investigate the effects of IL-36α on host response to sepsis.

Results: IL-36α production was significantly up-regulated during sepsis. IL-36α treatment reduced the mortality rate in mice with severe sepsis by cecal ligation and puncture. IL-36α-treated mice had more efficient bacterial clearance, inhibited tissue inflammation, improved organ injury, and reduced immune cell apoptosis. The therapeutic implication of these observations was also highlighted by the finding that specific blockade of IL-36α led to an increased mortality rate in mice with nonsevere sepsis. Furthermore, we found that IL-36α enhanced bacterial phagocytosis and killing by macrophages, thereby allowing local and systemic bacterial clearance. Importantly, macrophage depletion before the onset of sepsis eliminated IL-36α-mediated protection against sepsis.

Conclusions: Our results demonstrate that IL-36α plays an important role in the host defense response to sepsis and suggest a potential therapeutic role for IL-36α in sepsis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/infdis/jiw535DOI Listing
January 2017

Attenuated Streptococcus pneumoniae vaccine candidate SPY1 promotes dendritic cell activation and drives a Th1/Th17 response.

Immunol Lett 2016 11 5;179:47-55. Epub 2016 Sep 5.

College of Laboratory Medicine, Key Laboratory of Diagnostic Medicine (Ministry of Education), Chongqing Medical University, Chongqing 400016, China. Electronic address:

Streptococcus pneumoniae is one of the causative agent of pneumonia, meningitis, otitis media and sepsis. Vaccination is an effective strategy to combat S. pneumoniae invasion. We previously reported that SPY1, a novel attenuated vaccine candidate against S. pneumoniae, induces a protective immune response against pneumococcal infection in mice. However, underlying mechanisms have yet to be fully illustrated. To explore the mechanism of innate and adaptive immunities induced by SPY1. In this study, bone marrow-derived dendritic cells (DCs) of mice were infected with SPY1 and its parental wild-type strain D39, SPY1-infected DCs were co-cultured with homologous CD4+T cells or adoptive transfer to C57BL/6 mice. Results showed that SPY1 promoted DCs maturation with increased levels of surface molecules such as CD40, CD86, and MHC II, and upregulated the expression of proinflammatory cytokines, including TNF-α, IL-6, IL-12p40, IL-12p70 and IL-23. By contrast, D39 did not efficiently induce DCs activation and maturation. SPY1 could also activate MAPK and NF-κB signaling pathways in DC, but D39 unlikely affected this pathways. SPY1 treated DCs also induced Th1 and Th17 responses in vitro and in vivo. Our results supported the potential of SPY1 as a novel attenuated pneumococcus vaccine, because SPY1-activated DCs exhibit fully matured phenotype, initiated an adaptive immune response, and orchestrated Th1 and Th17 responses.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.imlet.2016.08.008DOI Listing
November 2016

Pollution, toxicity, and ecological risk of heavy metals in surface river sediments of a large basin undergoing rapid economic development.

Environ Toxicol Chem 2017 05 29;36(5):1149-1155. Epub 2016 Nov 29.

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.

A comprehensive and detailed investigation of heavy metal pollution, toxicity, and ecological risk assessment was conducted for the surface river sediments of the Haihe Basin in China based on 220 sampling sites selected in 2013. The average concentrations of Cr, Cu, Ni, Pb, and Zn in the sediments were 129 mg/kg, 63.4 mg/kg, 36.6 mg/kg, 50.0 mg/kg, and 202 mg/kg, respectively. As indicated by the geoaccumulation and pollution load indices, most surface river sediments of the Haihe Basin were contaminated with the investigated metals, especially in the junction region of the Zi Ya He and Hei Long Gang watersheds. The 5 heavy metals in the sediments all had anthropogenic sources, and the enrichment degrees followed the order Cu > Pb > Zn > Cr > Ni, with mean enrichment factors of 3.27, 2.77, 2.58, 1.81, and 1.44, respectively. According to the mean index of comprehensive potential ecological risk (38.9), the studied sediments of the Haihe Basin showed low potential ecological risk, but the sediments were potentially biologically toxic based on the mean probable effect concentration quotient (0.547), which may be the result of speciation of the 5 metals in the sediments. The results indicate that heavy metal pollution should be considered during the development of ecological restoration strategies in the Haihe Basin. Environ Toxicol Chem 2017;36:1149-1155. © 2016 SETAC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/etc.3650DOI Listing
May 2017

Progranulin Plays a Central Role in Host Defense during Sepsis by Promoting Macrophage Recruitment.

Am J Respir Crit Care Med 2016 11;194(10):1219-1232

1 Department of Laboratory Medicine.

Rationale: Progranulin, a widely expressed protein, has multiple physiological functions. The functional role of progranulin in the host response to sepsis remains unknown.

Objectives: To assess the role of progranulin in the host response to sepsis.

Methods: Effects of progranulin on host response to sepsis were determined.

Measurements And Main Results: Progranulin concentrations were significantly elevated in adult (n = 74) and pediatric (n = 26) patients with sepsis relative to corresponding healthy adult (n = 36) and pediatric (n = 17) control subjects, respectively. By using a low-lethality model of nonsevere sepsis, we observed that progranulin deficiency not only increased mortality but also decreased bacterial clearance during sepsis. The decreased host defense to sepsis in progranulin-deficient mice was associated with reduced macrophage recruitment, with correspondingly impaired chemokine CC receptor ligand 2 (CCL2) production in peritoneal lavages during the early phase of sepsis. Progranulin derived from hematopoietic cells contributed to host defense in sepsis. Therapeutic administration of recombinant progranulin not only rescued impaired host defense in progranulin-deficient mice after nonsevere sepsis but also protected wild-type mice against a high-lethality model of severe sepsis. Progranulin-mediated protection against sepsis was closely linked to improved peritoneal macrophage recruitment. In addition, CCL2 treatment of progranulin-deficient mice improved survival and decreased peritoneal bacterial loads during sepsis, at least in part through promotion of peritoneal macrophage recruitment.

Conclusions: This proof-of-concept study supports a central role of progranulin-dependent macrophage recruitment in host defense to sepsis, opening new opportunities to host-directed therapeutic strategy that manipulate host immune response in the treatment of sepsis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1164/rccm.201601-0056OCDOI Listing
November 2016

Streptococcus pneumoniae Endopeptidase O (PepO) Elicits a Strong Innate Immune Response in Mice via TLR2 and TLR4 Signaling Pathways.

Front Cell Infect Microbiol 2016 29;6:23. Epub 2016 Feb 29.

Department of Laboratory Medicine, Key Laboratory of Diagnostic Medicine (Ministry of Education), Chongqing Medical University Chongqing, China.

Interaction between virulence factors of Streptococcus pneumoniae and innate immune receptors elicits host responses through specific signaling pathways during infection. Insights into the signaling events may provide a better knowledge of the starting events for host-pathogen interaction. Here we demonstrated a significant induction of innate immune response elicited by recombinant S. pneumoniae endopeptidase O (rPepO), a newer pneumococcal virulence protein, both in vivo and in vitro. Intratracheal instillation of rPepO protein resulted in significant increase of cytokines production and neutrophils infiltration in mouse lungs. TLR2 or TLR4 deficient mice subjected to rPepO treatment showed decreased cytokines production, reduced neutrophils infiltration and intensified tissue injury as compared with WT mice. Upon stimulation, cytokines TNF-α, IL-6, CXCL1, and CXCL10 were produced by peritoneal exudate macrophages (PEMs) in a TLR2 and TLR4 dependent manner. rPepO-induced cytokines production was markedly decreased in TLR2 or TLR4 deficient PEMs. Further study revealed that cytokines induction relied on the rapid phosphorylation of p38, Akt and p65, not the activation of ERK or JNK. While in TLR2 or TLR4 deficient PEMs the activation of p65 was undetectable. Taken together, these results indicate for the first time that the newer pneumococcal virulence protein PepO activates host innate immune response partially through TLR2 and TLR4 signaling pathways.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fcimb.2016.00023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4770053PMC
November 2016

Rapamycin attenuates acute lung injury induced by LPS through inhibition of Th17 cell proliferation in mice.

Sci Rep 2016 Feb 18;6:20156. Epub 2016 Feb 18.

Department of Pulmonary and Critical Care Medicine, the Second Affiliated Hospital of Chongqing Medical University, 76 Linjiang Road, Yuzhong District, Chongqing 400010, China.

Th17 cells have been confirmed to increase neutrophils through cytokine secretions. ALI/ARDS are characterized as neutrophil infiltration in inflammation cases; however, there is conflicting information concerning the role of Th17 cells in ALI/ARDS, as well as their potential treatment value. We measured Th17-linear cytokines in the plasma of patients with sepsis-related ARDS. The consistently high levels of IL-17 and IL-22 in the nonsurvivors suggested that overreaction of the Th17-mediated immune response may be a risk factor for poor outcomes. Th17 linear cytokines were also increased in an LPS-induced murine model of acute lung injury, along with neutrophil accumulation. The mice that completely lacked IL-17 failed to accumulate and activate neutrophils. Lung inflammation was obviously attenuated in the IL-17(-)/(-) mice. Meanwhile, the neutrophil count was markedly increased in the healthy WT mice challenged with recombinant IL-22 and IL-17. Rapamycin attenuated lung injury by inhibiting the differentiation of Th17 cells through RORγt and STAT3 dysfunction. Furthermore, we demonstrated that SOCS3 and Gfi1, which were responsible for the molecular suppression of RORγt and STAT3, were up-regulated by rapamycin. These results point toward a pivotal view to treatment of ALI through weakening the proliferation of Th17 cells with rapamycin.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/srep20156DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4757870PMC
February 2016

Relationship Between Job Burnout and Neuroendocrine Indicators in Soldiers in the Xinjiang Arid Desert: A Cross-Sectional Study.

Int J Environ Res Public Health 2015 Dec 1;12(12):15154-61. Epub 2015 Dec 1.

Department of Public Health, Xinjiang Medical University, Urumqi 830011, China.

The purpose of this study was to explore the relationship between job burnout and neuroendocrine indicators in soldiers living in a harsh environment. Three hundred soldiers stationed in the arid desert and 600 in an urban area were recruited. They filled in the Chinese Maslach Burnout Inventory questionnaire. One hundred soldiers were randomly selected from each group to measure their levels of noradrenaline, serotonin, heat shock protein (HSP)-70, adrenocorticotropic hormone, and serum cortisol. Job burnout was more common in soldiers from urban areas than those from rural areas. Job burnout was significantly higher among soldiers stationed in the arid desert than those in urban areas. For soldiers in the arid desert, the levels of HSP-70, serum cortisol, and adrenocorticotropic hormone were significantly higher than in soldiers in urban areas. Correlation analyses showed that the degree of job burnout was weakly negatively correlated with the level of HSP-70. Being an only child, HSP-70 levels, cortisol levels, and ACTH levels were independently associated with job burnout in soldiers stationed in the arid desert. A higher level of job burnout in soldiers stationed in arid desert and a corresponding change in neuroendocrine indicators indicated a correlation between occupational stress and neurotransmitters.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph121214977DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4690913PMC
December 2015

Modified HPLC-ESI-MS Method for Glycated Hemoglobin Quantification Based on the IFCC Reference Measurement Procedure and Its Application for Quantitative Analyses in Clinical Laboratories of China.

J Clin Lab Anal 2016 Sep 29;30(5):457-63. Epub 2015 Oct 29.

Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China.

Background: The level of glycated hemoglobin (HbA1c ) has been recognized as an important indicator of long-term glycemic control. However, the HbA1c measurement is not currently included as a diagnostic determinant in China. Current study aims to assess a candidate modified International Federation of Clinical Chemistry reference method for the forthcoming standardization of HbA1c measurements in China.

Methods: The HbA1c concentration was measured using a modified high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method. The modified method replaces the propylcyanide column with a C18 reversed-phase column, which has a lower cost and is more commonly used in China, and uses 0.1% (26.5 mmol/l) formic acid instead of trifluoroacetic acid. Moreover, in order to minimize matrix interference and reduce the running time, a solid-phase extraction was employed. The discrepancies between HbA1c measurements using conventional methods and the HPLC-ESI-MS method were clarified in clinical samples from healthy people and diabetic patients. Corresponding samples were distributed to 89 hospitals in Beijing for external quality assessment.

Results: The linearity, reliability, and accuracy of the modified HPLC-ESI-MS method with a shortened running time of 6 min were successfully validated. Out of 89 hospitals evaluated, the relative biases of HbA1c concentrations were < 8% for 74 hospitals and < 5% for 60 hospitals. Compared with other conventional methods, HbA1c concentrations determined by HPLC methods were similar to the values obtained from the current HPLC-ESI-MS method.

Conclusion: The HPLC-ESI-MS method represents an improvement over existing methods and provides a simple, stable, and rapid HbA1c measurement with strong signal intensities and reduced ion suppression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jcla.21879DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6807171PMC
September 2016

Progranulin is preferentially expressed in patients with psoriasis vulgaris and protects mice from psoriasis-like skin inflammation.

Immunology 2015 Jun;145(2):279-87

Department of Dermatology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China; Department of Laboratory Medicine, Key Laboratory of Diagnostic Medicine designated by the Ministry of Education, Chongqing Medical University, Chongqing, China.

Progranulin (PGRN) is a multi-functional protein known to be involved in inflammation. Recent studies have found that PGRN has dual roles in inflammation and exerts anti-inflammatory and pro-inflammatory function in different diseases. However, the role of PGRN in psoriasis has not been fully elucidated. Here, we detected preferential expression of PGRN in human psoriatic lesions and serum. Moreover, serum PGRN/tumour necrosis factor-α ratio was negatively correlated with disease severity. To investigate the role of PGRN in the pathogenesis of psoriasis, we used wild-type (WT) and PGRN(-/-) mice in a model of 12-O-tetradecanoylphorbol 13-acetate (TPA) -induced psoriasis-like inflammation. We demonstrated that PGRN expression was dramatically enhanced in the psoriasis-like lesions of TPA-treated WT mice, in accordance with human psoriatic lesions. Surprisingly, PGRN(-/-) mice were more sensitive to the development of TPA-induced psoriasis-like inflammation. The mechanism underlying this increased sensitivity of PGRN(-/-) mice to TPA-induced psoriasis-like inflammation was impaired differentiation of regulatory T cells in lymph nodes and decreased recruitment of these cells in the affected skin, which results in more severe inflammation. Hence, in WT mice, PGRN promotes differentiation and recruitment of regulatory T cells at the site of inflammation, which protects the skin from an exaggerated psoriasis-like inflammatory response.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/imm.12446DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4427392PMC
June 2015

Compound 48/80 acts as a potent mucosal adjuvant for vaccination against Streptococcus pneumoniae infection in young mice.

Vaccine 2015 Feb 14;33(8):1008-16. Epub 2015 Jan 14.

College of Laboratory Medicine, Key Laboratory of Diagnostic Medicine (Ministry of Education), Chongqing Medical University, Chongqing 400016, China. Electronic address:

Streptococcus pneumoniae, a major respiratory pathogen, is a leading cause of death among children worldwide. Mucosal vaccination is a recommended method to prevent respiratory infection. However, development of mucosal vaccination is usually hindered due to the lack of safe and effective mucosal adjuvants. Mast cell activator compound 48/80 (C48/80) has been used as a mucosal adjuvant in immunization of adult mice, but its adjuvanticity is not clear in the immunization of young mice. In this study, the adjuvanticity of C48/80 was evaluated when intranasally co-administrated with a pneumococcal vaccine candidate strain SPY1 in a young mice model in comparison with a classical mucosal adjuvant cholera toxin (CT) and a relatively safe mucosal adjuvant Pam2CSK4. All three adjuvants enhanced antibody responses, whereas serum IgG titers were maintained at a stable level during the 3 months after the last immunization only in the SPY1+C48/80 and SPY1+CT groups. Furthermore, both the SPY1+CT group and the SPY1+C48/80 group induced strong Th17 immune response. Notably, C48/80 showed the exceptional ability to promote the clearance of nasal pneumococcal colonization which CT and Pam2CSK4 did not show. We found that C48/80's ability to induce protection against nasal pneumococcal colonization depended on B cells and IL-17A. Additionally, C48/80, as a mucosal adjuvant, showed a greater ability to protect young mice against lethal pneumococcal infection than CT. In comparison with CT, C48/80 also showed a favorable safety. These results reveal a promising perspective for using C48/80 as a mucosal adjuvant to improve protection against pneumococcal diseases early in life.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.vaccine.2015.01.013DOI Listing
February 2015

Dynamics of heavy metals and phosphorus in the pore water of estuarine sediments following agricultural intensification in Chao Lake Valley.

Environ Sci Pollut Res Int 2015 May 18;22(10):7948-53. Epub 2014 Dec 18.

State Key Laboratory on Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 10085, China,

Previous research has revealed that agricultural intensification in the Chao Lake Valley since the 1980s has led to significant heavy metal and phosphorus (P) contamination of estuarine sediments in this region. However, the pore water plays a more important role than do sediments in the cycling of nutrients and metals in estuarine ecosystems. Average concentrations of Cd, Cr, Ni, Pb, and P in the pore water of estuarine sediments were 0.634, 3.11, 4.98, 3.98, and 49.9 μg L(-1), respectively. Average diffusive fluxes of these elements from the pore water to overlying water were -0.015, 0.058, 0.768, -0.238, and 20.0 μg m(-2) d(-1), respectively. Compared with similar studies, the values of heavy metal fluxes were low, indicating minimal diffusion between sediments and overlying waters; however, P diffusion from the sediment pore water to overlying water was high, indicating that the sediments may be a direct source of P to overlying water. Since P is a major cause of algal blooming in agricultural estuaries of Chao Lake, the obtained results could be useful in developing effective management strategies to control pollution in the Chao Lake Valley.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11356-014-3945-xDOI Listing
May 2015

Interleukin 4 Deficiency Reverses Development of Secondary Pseudomonas aeruginosa Pneumonia During Sepsis-Associated Immunosuppression.

J Infect Dis 2015 May 8;211(10):1616-27. Epub 2014 Dec 8.

Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University.

Background: Interleukin 4 (IL-4) is an important cytokine that may modulate development of secondary bacterial pneumonia during sepsis-induced immunosuppression.

Methods: We established an experimental model of cecal ligation and puncture (CLP)-induced sublethal polymicrobial sepsis followed by secondary Pseudomonas aeruginosa pulmonary infection,

Results:  IL-4-deficient mice that underwent CLP were resistant to secondary pulmonary P. aeruginosa infection. As compared to wild-type mice, IL-4 knockout (KO) mice displayed improved survival and better bacterial clearance. Furthermore, IL-4 KO mice exhibited enhanced lung inflammation, neutrophil recruitment to airspaces, and elevated pulmonary cytokine production, with significantly increased tumor necrosis factor α (TNF-α) production. Neutralization of TNF-α could reverse the enhanced protection against secondary P. aeruginosa pneumonia in septic IL-4 KO mice, indicating that the resistance of septic IL-4 KO mice to secondary bacterial pneumonia was partially mediated by TNF-α. In addition, IL-4 priming displayed marked impairment of the ability of alveolar macrophages to phagocytose and kill P. aeruginosa in vitro, and this defect was associated with decreased activation of Akt, JNK, p38MAPK, and ERK intracellular signaling pathways by IL-4. Finally, neutralization of IL-4 in septic mice could improve survival and clearance of bacteria from the lungs of septic mice infected with P. aeruginosa.

Conclusions: Our findings provide new insight for immunopathologic mechanisms of sepsis-induced secondary bacterial pneumonia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/infdis/jiu668DOI Listing
May 2015
-->