Investigating the evolution of reactive species in the CuO-mediated peroxymonosulfate activation process

The utilization of copper oxide (CuO) as a catalyst in the peroxymonosulfate (PMS) activation process holds great promise for effectively degrading aqueous organic pollutants, while the relevant mechanism remains inadequately understood. In this study, we delve into the evolution pathways of reactive species in the CuO/PMS system through a comprehensive series of experimental analyses. Our findings indicate that various reactive species are generated in the CuO/PMS system with the specific sequence, where the decomposition of surface Cu(II)-OOSO3- leads to the formation of surface Cu(III) species, which are responsible for the subsequent generation of HO•. The reactivity of these reactive species and the sequence of their generation explain the distinct oxidation behaviors of pollutants with different values of ionization potential (IP). In addition, singlet oxygen (1O2) may be produced during the PMS activation process, while its involvement in the oxidation of substrates is deemed negligible. This investigation presents a novel perspective, enhancing our comprehension of the mechanism underlying transition metal-mediated PMS activation processes. ENVIRONMENTAL IMPLICATION: The removal of refractory organic contaminations in water constitutes a fundamental concern within the realm of environmental pollution management. Peroxymonosulfate activation induced by transition metal oxides has garnered significant recognition as a promising technological approach for the degradation of aqueous organic contaminants, while the underlying mechanism remains enigmatic. In this study, we systematically investigate the evolution pathways of reactive species in the CuO/peroxymonosulfate system to reveal the mystery of the reaction mechanism between CuO and peroxymonosulfate. The outcomes of our study contribute to enhancing the practical applicability of transition metal-triggered PMS activation processes.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Exploration for cobalt/nitrogen-doped catalyst to creatinine degradation via peroxymonosulfate activation: toxicity evaluation, statistical modeling, and mechanisms study

Developing multifunctional catalysts applied in diversiform modes via advanced oxidation processes (AOPs) is a promising and attractive approach for organic pollution degradation. Herein, a novel hollow bamboo-like structural cobalt/nitrogen-doped carbonized material (CoC/N) was employed as a catalyst for AOPs, in which CoC/N was prepared in situ through calcining a Co-based coordination polymer. When CoC/N was utilized as a peroxymonosulfate (PMS) activator, the catalyst stood out prominent activities for effective CA oxidation. Furthermore, a five-level central composite rotatable design (CCRD) model describing CA decay as a function of PMS concentration, CoC/N dosage, and solution pH value was successfully constructed and engaged to explore the optimal operating conditions. Finally, the possible degradation mechanism of CA in CoC/N-PMS system was proposed by quantum chemistry calculation and LC/MS analysis. This work shed light on the structural morphology of the catalyst and its PMS synergy degradation pathway, which promotes its applications in miscellaneous pollutant degradation. A new Co/N-doped material was used to degrade unconventionality organic pollutant creatinine (CA) for the first time, in which the scientific approaches of five-level central composite rotatable design (CCRD) model, response surface methodology (RSM) and density function theory (DFT) were employed to evaluate the material performance and CA degradation pathway. The toxicity evaluation, statistical modeling and mechanisms study have been investigated meticulously.

Wearable sensor platforms for real-time monitoring and early warning of metabolic disorders in humans

Nowadays, the prevalence of metabolic syndromes (MSs) has attracted increasing concerns as it is closely related to overweight and obesity, physical inactivity and overconsumption of energy, making the diagnosis and real-time monitoring of the physiological range essential and necessary for avoiding illness due to defects in the human body such as higher risk of cardiovascular disease, diabetes, stroke and diseases related to artery walls. However, the current sensing techniques are inconvenient and do not continuously monitor the health status of humans. Alternatively, the use of recent wearable device technology is a preferable method for the prevention of these diseases. This can enable the monitoring of the health status of humans in different health domains, including environment and structure. The use wearable devices with the purpose of facilitating rapid treatment and real-time monitoring can decrease the prevalence of MS and long-time monitor the health status of patients. This review highlights the recent advances in wearable sensors toward continuous monitoring of blood pressure and blood glucose, and further details the monitoring of abnormal obesity, triglycerides and HDL. We also discuss the challenges and future prospective of monitoring MS in humans.

Contribution of differential alteration in oxidative stress and anti-oxidation related molecular signals to toxicity difference between atrazine and its main metabolites in nematodes

As a widely used herbicide, atrazine and its two main metabolites of deethylatrazine (DEA) and deisopropylatrazine (DIA) pose an exposure risk for both human beings and animals in the environment. In this study, Caenorhabditis elegans was selected as an in vivo model to compare the toxicity between atrazine and its main metabolites. Upon exposure from the larval stage L1 to adult day 3, both DEA and DIA showed less toxicity on locomotion and reproduction compared with atrazine at concentration of 0.001, 0.01 0.1 and 1 mg/L for parental generation. In addition, exposure to DEA and DIA at concentration of 0.1 mg/L also induced less transgenerational toxicity on locomotion than exposure to atrazine for both parental generation and offspring of F1-F4. Accordingly, exposure to DEA and DIA caused less ROS production and alteration in the expression of some genes (mev-1, gas-1, and clk-1) governing oxidative stress compared to atrazine. Meanwhile, DEA and DIA lead to less increase in expression of superoxide dismutase genes (sod-2 and sod-3) and SOD-3::GFP than atrazine. Moreover, atrazine and its two main metabolites differentially activated the daf-16 encoding FOXO transcriptional factor in insulin signaling pathway during the control of downstream target of SOD-3. Overall, our results highlighted the important role of oxidative stress and anti-oxidation related molecular signals in mediating toxicity of atrazine, DEA and DIA, which provided a novel explanation for the different toxicity between atrazine and its main metabolites.

Remediation technologies for neonicotinoids in contaminated environments: Current state and future prospects

Neonicotinoids (NEOs) are synthetic insecticides with broad-spectrum insecticidal activity and outstanding efficacy. However, their extensive use and persistence in the environment have resulted in the accumulation and biomagnification of NEOs, posing significant risks to non-target organisms and humans. This review provides a summary of research history, advancements, and highlighted topics in NEOs remediation technologies and mechanisms. Various remediation approaches have been developed, including physiochemical, microbial, and phytoremediation, with microbial and physicochemical remediation being the most extensively studied. Recent advances in physiochemical remediation have led to the development of innovative adsorbents, photocatalysts, and optimized treatment processes. High-efficiency degrading strains with well-characterized metabolic pathways have been successfully isolated and cultured for microbial remediation, while many plant species have shown great potential for phytoremediation. However, significant challenges and gaps remain in this field. Future research should prioritize isolating, domesticating or engineering high efficiency, broad-spectrum microbial strains for NEO degradation, as well as developing synergistic remediation techniques to enhance removal efficiency on multiple NEOs with varying concentrations in different environmental media. Furthermore, a shift from pipe-end treatment to pollution prevention strategies is needed, including the development of green and economically efficient alternatives such as biological insecticides. Integrated remediation technologies and case-specific strategies that can be applied to practical remediation projects need to be developed, along with clarifying NEO degradation mechanisms to improve remediation efficiency. The successful implementation of these strategies will help reduce the negative impact of NEOs on the environment and human health.

Combinational exposure to hydroxyatrazine increases neurotoxicity of polystyrene nanoparticles on Caenorhabditis elegans

Using Caenorhabditis elegans as an animal model, we investigated combinational effect between 2-hydroxyatrazine (HA) and polystyrene nanoparticle (PS-NP) on function and development of D-type motor neurons. Exposure to HA (10 and 100 μg/L) alone caused decreases in body bend, head thrash, and forward turn and increase in backward turn. Exposure to 100 μg/L HA also caused neurodegeneration of D-type motor neurons. Moreover, combinational exposure to HA (0.1 and 1 μg/L) induced enhancement in PS-NP (10 μg/L) toxicity in inhibiting body bend, head thrash, and forward turn, and in increasing backward turn. In addition, combinational exposure to HA (1 μg/L) could result in neurodegeneration of D-type motor neurons in PS-NP (10 μg/L) exposed nematodes. Combinational exposure to HA (1 μg/L) and PS-NP (10 μg/L) increased expressions of crt-1, itr-1, mec-4, asp-3, and asp-4, which govern the induction of neurodegeneration. Moreover, combinational exposure to HA (0.1 and 1 μg/L) strengthened PS-NP (10 μg/L)-induced decreases in glb-10, mpk-1, jnk-1, and daf-7 expressions, which encode neuronal signals regulating response to PS-NP. Therefore, our results demonstrated the effect of combinational exposure to HA and nanoplastics at environmentally relevant concentrations in causing toxic effect on nervous system in organisms.

Occurrence, spatial distributions, and temporal trends of bisphenol analogues in an E-waste dismantling area: Implications for risk assessment

The environmental occurrences of bisphenol analogues (BPs) have been extensively reported, whereas their concentration profile, spatial distribution, and temporal trend in e-waste dismantling area are still poorly understood. Herein, typical BPs (BPA, BPS, TBBPA, TBBPA-DHEE, and TBBPA-MHEE) were investigated in water, soil, and biological samples from three representative regions (FJT, JJP, and RIB) in e-waste recycling area in Taizhou, Zhejiang Province. Overall, the detection frequency of BPs in all samples was 100 %, confirming widespread presence of BPs in e-waste recycling area. Wherein, BPA was the predominant BPs in water (33.3 %) and soil samples (34.9 %), but TBBPA accounted for the largest proportion (41.3 %) in biological samples. In addition, the concentration of BPs in FJT was lower than that in JJP and RIB owing to the renovations on FJT by the local government in recent years, whereas the higher BPs level in RIB implied that elevated BPs contents was related to massive e-waste dismantling activities. From 2017 to 2021, a decreased trend of BPs concentration was observed in FJT, but aggravation of BPs levels in RIB was caused by the ongoing e-waste dismantling. The risk assessment revealed that the BPs in e-waste recycling area posed a low ecological and human health risk. Our finding could provide a valuable reference for the development of strict legislation systems related to e-waste management in China.

Effects of perfluorobutane sulfonate and perfluorooctane sulfonate on lipid homeostasis in mouse liver

Perfluorobutane sulfonate (PFBS), an alternative to perfluorooctane sulfonate (PFOS), has been increasingly used in recent years. However, emerging evidence has raised concerns about the potential health risks of PFBS. Here, the toxicityof low-dose PFBS on livers was explored and compared with that of PFOS. Adult C57BL/6 mice were exposed to 10 μg/L, 500 μg/L PFBS, or 500 μg/L PFOS for 28 days through drinking water. At the phenotypic level, no liver damage was observed in the 10 μg/L PFBS group. The cell apoptosis and decrease of CAT activities were observed in the 500 μg/L PFBS group, while accumulation of lipid droplets, increase of CAT activities and TAG levels were found in the 500 μg/L PFOS group. Lipidomics analysis revealed that 138, 238, and 310 lipids were significantly changed in the 10 μg/L, 500 μg/L PFBS and 500 μg/L PFOS groups, respectively. The two PFBS-treated groups induced similar global lipid changes in a dose-dependent manner, which were distinct from PFOS. Overall, PFBS exposure induced an increase in phosphatidylcholines and sphingomyelins, but a decrease in phosphatidylinositol. PFOS exposure caused an increase in triacylglycerols. This study provides more evidence on the health hazards caused by exposure to low-dose PFBS.

Long-term exposure to polystyrene nanoparticles causes transgenerational toxicity by affecting the function and expression of MEV-1 and DAF-2 signals in Caenorhabditis elegans

In this study, we determined the roles of oxidative stress and related signals in mediating transgenerational toxicity of 30 nm polystyrene nanoparticles (PS-NPs) in Caenorhabditis elegans. Using brood size and locomotion behavior as endpoints, exposure to 1-100 μg/L PS-NPs caused transgenerational toxicity. Meanwhile, the activation of reactive oxygen species (ROS) was also observed transgenerationally after exposure to 1-100 μg/L PS-NPs. After exposure to 1 μg/L PS-NPs, the transgenerational toxicity was monitored until F2 generation (F2-G) and recovered at F3-G. At the F1-G of 1 μg/L PS-NPs-exposed nematodes, RNAi knockdown of daf-2 with function to inhibit oxidative stress suppressed the transgenerational toxicity and increased the mitochondrial SOD-3 expression. In contrast, at F3-G of 1 μg/L PS-NPs-exposed nematodes, RNAi knockdown of mev-1 with function to induce oxidative stress promoted locomotion and brood size, and suppressed the SOD-3 expression. Moreover, we observed the dynamic expressions of mev-1, daf-2, and sod-2 transgenerationally after exposure to 1 μg/L PS-NPs at P0-G, which further suggested the involvement of MEV-1, DAF-2, and SOD-3 in affecting induction of transgenerational PS-NP toxicity. Therefore, we provided the evidence to suggest the roles of oxidative stress activation and related molecular signals in mediating induction of transgenerational PS-NP toxicity. Our data highlights the crucial function of oxidative stress-related signals during induction of transgenerational PS-NP toxicity.

The use of different sublethal endpoints to monitor atrazine toxicity in nematode Caenorhabditis elegans

In this work, Caenorhabditis elegans was employed as an in vivo model to determine the toxic effects of atrazine at different concentrations. After the exposure period from the larval stage L1 to adulthood day 1, atrazine (10 mg/L) significantly decreased the body length and lifespan of nematodes. In addition, exposure to ≥0.01 mg/L atrazine remarkably increased the intestinal reactive oxygen species (ROS) levels and reduced locomotion behavior of nematodes, while exposure to ≥ 1 mg/L atrazine decreased the brood size of nematodes. Moreover, atrazine (0.001-0.1 mg/L) upregulated the expression levels of hsp-6::GFP and hsp-6/60 in nematodes, indicating the activation of mitochondrial unfolded protein response (mtUPR). On the contrary, atrazine (1-10 mg/L) downregulated the expression levels of hsp-6::GFP and hsp-6/60 in nematodes. Furthermore, mtUPR induction governed by the RNAi knockdown of atfs-1 could increase the vulnerability of nematodes against atrazine toxicity. Overall, our findings highlighted the dynamic responses of nematodes toward different concentrations of atrazine, which could be monitored using different sublethal endpoints as bioindicators.

Reproductive toxicity and underlying mechanisms of di(2-ethylhexyl) phthalate in nematode Caenorhabditis elegans

DEHP (di(2-ethylhexyl) phthalate) is an endocrine disruptor commonly found in plastic products that has been associated with reproduction alterations, but the effect of DEHP on toxicity is still widely unknown. Using DEHP concentrations of 10, 1, and 0.1 mg/L, we showed that DEHP reduced the reproductive capacity of Caenorhabditis elegans after 72 hr. of exposure. DEHP exposure reduced the reproductive capacity in terms of decreased brood sizes, egg hatchability (0.1, 1 and 10 mg/L), and egg-laying rate (1 and 10 mg/L), and increased numbers of fertilized eggs in the uterus (1 and 10 mg/L). DEHP also caused damage to gonad development. DEHP decreased the total number of germline cells, and decreased the relative area of the gonad arm of all exposure groups, with worms in the 1 mg/L DEHP exposure group having the minimum gonad arm area. Additionally, DEHP caused a significant concentration-dependent increase in the expression of unc-86. Autophagy and ROS contributed to the enhancement of DEHP toxicity in reducing reproductive capacity, and glutathione peroxidase and superoxide dismutase were activated as the antioxidant defense in this study. Hence, we found that DEHP has a dual effect on nematodes. Higher concentration (10 mg/L) DEHP can inhibit the expression of autophagy genes (atg-18, atg-7, bec-1, lgg-1 and unc-51), and lower concentrations (0.1 and 1 mg/L) can promote the expression of autophagy genes. Our data highlight the potential environmental risk of DEHP in inducing reproductive toxicity toward the gonad development and reproductive capacity of environmental organisms.

Indirect competitive-structured electrochemical immunosensor for tetrabromobisphenol A sensing using CTAB-MnO2 nanosheet hybrid as a label for signal amplification

Tetrabromobisphenol A (TBBPA) is a kind of brominated flame retardant that is usually added to products to reduce their flame retardancy. However, its extensive use has resulted in their residues being found in the environment, which is very harmful. Herein, an indirect competitive immunosensor has been established for TBBPA detection based on the signal amplification system. Pd nanospheres in situ reduced on the surface of MnO₂ nanosheet hybrid (MnO₂/Pd) was used as the label for the secondary antibody through the Pd-N bond, and gold-toluidine blue composite was loaded onto MWCNTs (MWCNTs/Au-TB), which functioned as the platform for the immunosensor. The spherical structure of Pd had abundant catalytic active sites, which enhanced the catalytic activity of MnO₂/Pd as the label, hence amplifying the signal response. Besides, MWCNTs/Au-TB improved electron transfer and produced a strong signaling pathway for immobilizing antigens through the Au-NH₂ bond, which can specifically recognize primary antibodies to improve sensitivity. The immunosensor had a linear concentration range of 0-81 ng/mL, a low detection limit of 0.17 ng/mL (S/N = 3), with good stability, selectivity, and reproducibility based on the above advantages. Additionally, the acceptable accuracy and recoveries (recoveries, 92-124%; CV, 3.3-8.8%) in the real water sample analysis indicated that this strategy is promising for emerging pollutant analysis.

Untargeted Metabolomic Profiling of the Correlation Between Prognosis Differences and PD-1 Expression in Sepsis: A Preliminary Study

Objectives: The mortality rate of sepsis remains very high. Metabolomic techniques are playing increasingly important roles in diagnosis and treatment in critical care medicine. The purpose of our research was to use untargeted metabolomics to identify and analyze the common differential metabolites among patients with sepsis with differences in their 7-day prognosis and blood PD-1 expression and analyze their correlations with environmental factors.

Methods: Plasma samples from 18 patients with sepsis were analyzed by untargeted LC-MS metabolomics. Based on the 7-day prognoses of the sepsis patients or their levels of PD-1 expression on the surface of CD4+ T cells in the blood, we divided the patients into two groups. We used a combination of multidimensional and monodimensional methods for statistical analysis. At the same time, the Spearman correlation analysis method was used to analyze the correlation between the differential metabolites and inflammatory factors.

Results: In the positive and negative ionization modes, 16 and 8 differential metabolites were obtained between the 7-day death and survival groups, respectively; 5 and 8 differential metabolites were obtained between the high PD-1 and low PD-1 groups, respectively. We identified three common differential metabolites from the two groups, namely, PC (P-18:0/14:0), 2-ethyl-2-hydroxybutyric acid and glyceraldehyde. Then, we analyzed the correlations between environmental factors and the common differences in metabolites. Among the identified metabolites, 2-ethyl-2-hydroxybutyric acid was positively correlated with the levels of IL-2 and lactic acid (Lac) (P < 0.01 and P < 0.05, respectively).

Conclusions: These three metabolites were identified as common differential metabolites between the 7-day prognosis groups and the PD-1 expression level groups of sepsis patients. They may be involved in regulating the expression of PD-1 on the surface of CD4+ T cells through the action of related environmental factors such as IL-2 or Lac, which in turn affects the 7-day prognosis of sepsis patients.

The effect of combined exposure of zinc and nickel on the development of zebrafish

Excessive accumulation of Zn²⁺ or Ni²⁺ can cause various problems to aquatic animals. In this study, the developmental toxicity induced by individual or combined exposure of Zn²⁺ and Ni²⁺ to zebrafish embryos and larvae were evaluated to better understand the interaction between Zn²⁺ and Ni²⁺ . Both of individual and combined exposure of Zn²⁺ and Ni²⁺ could cause obvious developmental toxicity, which mainly occurred after hatching, at a concentration-dependent manner. The calculated 168-h LC₅₀ were 2.79 mg/L for Zn²⁺ and 7.44 mg/L for Ni²⁺ . The interaction of Zn²⁺ and Ni²⁺ based on mortality was found to be an antagonism. Various malformations, including tail curving, spinal curvature, pericardial edema, and yolk sac edema, were observed with significant effects on body length and heartbeat rates after exposure of Zn²⁺ and Ni²⁺ . Meanwhile, some genes related to cardiovascular development and bone formation were mainly down-regulated by the individual and combined exposure of Zn²⁺ and Ni²⁺ . The individual exposure was more toxic than combined exposure because the interaction of Zn²⁺ and Ni²⁺ was determined to be an antagonism. The down-regulation of genes related to cardiovascular development and bone formation may contribute to the observed malformation and decreases of body length and heartbeat rates.

Developmental neurotoxicity of low concentrations of bisphenol A and S exposure in zebrafish

The vulnerability to environmental insults is heightened at early stages of development. However, the neurotoxic potential of bisphenol A (BPA) and bisphenol S (BPS) at developmental windows remains unclear. To investigate the mechanisms mediating the developmental neurotoxicity, zebrafish embryos were treated with 0.01, 0.03, 0.01, 0.3, 1 μM BPA/BPS. Also, we used Tg(HuC:GFP) zebrafish to investigate whether BPA/BPS could induce neuron development. The reduction in body length, and increased heart rate were significant in 0.3 and 1 μM BPA/BPS groups. The green fluorescence protein (GFP) intensity increased at 72 hpf and 120 hpf in Tg(HuC:GFP) larvae which was consistent with the increased mRNA expression of elval3 following BPS treatments, an indication of the plausible effect of BPS on embryonic neuron development. Additionally, BPA/BPS treatments elicited hyperactivity and reduced static time in zebrafish larvae, suggesting behavioral alterations. Moreover, qRT-PCR results showed that BPA and BPS could interfere with the normal expression of development-related genes vegfa, wnt8a, and mstn1 at the developmental stages. The expression of neurodevelopment-related genes (ngn1, elavl3, gfap, α1-tubulin, mbp, and gap43) were significantly upregulated in BPA and BPS treatments, except for the remarkable downregulation of mbp and gfap elicited by BPA at 48 (0.03 μM) and 120 hpf (0.3 μM) respectively; ngn1 at 48 hpf for 0.1 μM BPS. Overall, our results highlighted that embryonic exposure to low concentrations of BPA/BPS could be deleterious to the central nervous system development and elicit behavioral abnormalities in zebrafish at developmental stages.

Male reproductive toxicity involved in spermatogenesis induced by perfluorooctane sulfonate and perfluorooctanoic acid in Caenorhabditis elegans

As a persistent organic pollutant, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have gained increasing research attention over recent years because of their potential risk to humans and the environment. In this paper, we investigated the reproductive toxicity of these pollutants using a C. elegans model to evaluate spermatogenesis throughout the entire developmental cycle of him-5 mutant by exposing to 0.001, 0.01, and 0.1 mmol/L PFOS or PFOA for 48 h. Experimental results suggested that PFOS and PFOA exposure led to reductions in brood size, germ cell number, spermatid size, and motility, and increases in rate of malformation spermatids. Analysis of variance (ANOVA) showed that exposure to PFOS resulted in higher levels of damage than PFOA in germ cells only in 0.001 mmol/L exposure group. RT-qPCR was used to further investigate the expression of genes associated with different stages of spermatogenesis, such as mitosis and meiosis, fibrous body-membranous organelles (FB-MOs), and sperm activation. The expression levels of wee-1.3, spe-4, spe-6, and spe-17 genes were increased, while those of puf-8, spe-10, fer-1, swm-1, try-5, and spe-15 genes were decreased. Our results suggesting that PFOS or PFOA may cause spermatogenesis damage by disrupting the mitotic proliferation, meiotic entry, formation of the MOs, fusion of the MOs and plasma membrane (PM), and pseudopods. Loss-of-function studies using puf-8 and spe-10 mutants revealed spe-10 gene was specifically involved in PFOS- or PFOA-induced reproductive toxicity via regulating one or more critical palmitoylation events, while puf-8 gene was not direct target of PFOS and PFOA, and PFOS and PFOA may act on the upstream gene of puf-8, thus affecting reproductive ability. Taken together, these results demonstrate the potential adverse impact of PFOS and PFOA exposure on spermatogenesis and provide valuable data for PFC risk assessment. Grapical abstract.

Non-targeted metabolomic profiling of atrazine in Caenorhabditis elegans using UHPLC-QE Orbitrap/MS

The widespread use of the herbicides Atrazine (ATR) has been raised attention due to its ubiquitous occurrence in the environment. As an endocrine disruptor, ATR causes reproductive, immune, nervous system toxicity in biota. In this study, we aimed to investigate metabolic profile characteristics and potential metabolic biomarker that reflects specific damage in toxic effect after ATR exposure. Hence, a metabolomics study was performed to determine the significantly affected metabolites and the reproduction and locomotion of C. elegans were investigated. Mediation analysis was used to evaluate the mediating effect of metabolites on association between ATR exposure and toxic effect. ATR (≥0.04 mg/L) caused the significant dose dependent reduction of brood size and locomotion behavior, however, the body length and width were significantly decreased only in 40 mg/L group. These results suggesting that brood size, head thrashes and body bends are more sensitive indictor to assessment ATR toxicity in C. elegans. Meanwhile, metabolomics analysis revealed that ATR exposure can induce metabolic profiles significant alterations in C. elegans. We found that 9 metabolites significantly increased and 18 metabolites significantly decreased, such as phosphatidylcholine, GMP, CDP-choline, neopterin etc. Those alteration of metabolites were mainly involved in the pathways: glycerophospholipid metabolism, glycolysis/gluconeogenesis, folate biosynthesis, glycine, serine and threoninemetabolism, pyrimidine and purine metabolism. Overall, these changes are signs of possible oxidative stress and ATP synthesis disruption modification. Mediation analysis showed a significant indirect effect of ATR exposure on brood size, via 7,8-dihydroneopterin 2',3'-cyclic-p, and phosphatidylcholine might mediate association between ATR exposure and body bends, suggesting that 7,8-dihydroneopterin 2',3'-cyclic-p and phosphatidylcholine might be potentially specificity marker for brood size and body bend respectively. This preliminary analysis investigates metabolic characteristics in C. elegans after ATR exposure, helping to understand the pathways involved in the response to ATR exposure and provide potential biomarkers for the safety evaluation of ATR.

Acute toxicity of fluazinam to aquatic organisms and its bioaccumulation in Brachydanio rerio

Fluazinam (FZN) is a dinitroaniline fungicide. To evaluate the environmental risk of FZN in aquatic environments and ascertain the potential danger to typical aquatic organisms in China, the acute toxicity of FZN to representative aquatic organisms, including Brachydanio rerio, Chlorella vulgaris Beij., Daphnia magna Straus, and Xenopus laevis, was measured, and its bioaccumulation properties in Brachydanio rerio were further investigated. The results showed that the acute toxicity of FZN to Brachydanio rerio and Xenopus laevis is extremely high, and the bioaccumulation factor BCF_8d of FZN in Brachydanio rerio ranges between 2287 and 3570, implying that it has high bioaccumulation properties. FZN poses a strong environmental risk for aquatic organisms and possesses great bioaccumulation properties, which may cause pollution to aquatic environments.

A combination of three probiotic strains for treatment of acute diarrhoea in hospitalised children: an open label, randomised controlled trial

Acute diarrhoea continues to be a leading cause of morbidity, hospitalisation, and mortality worldwide, and probiotics have been proposed as a complementary therapy in the treatment of acute diarrhoea. The goal of this study is to assess the efficacy and safety of three combined probiotic strains, Bifidobacterium lactis Bi-07, Lactobacillus rhamnosus HN001, and Lactobacillus acidophilus NCFM, as an adjunct to rehydration therapy in treatment of acute watery diarrhoea in hospitalised children. Eligible diarrheal children were randomised into intervention group (IG, n=96, conventional treatment for diarrhoea in combination with probiotics) and control group (CG, n=98, conventional treatment for diarrhoea without probiotics). The primary assessments of this study were duration of diarrhoea and hospital stay and improvement in diarrhoea symptoms. Significantly more children in the IG showed improvements in diarrhoea (defined as a decrease of stool frequency to no more than four times per day and an improved stool consistency within 24-48 h after the treatment) than those in the CG (96.9 vs 79.6%, P<0.05). Children supplemented with the mixed strains had a 22.5 h shorter (121.4±13.7 h vs 143.9±19.8 h) mean duration of diarrhoea and 1.2 d shorter hospital stays (5.1±1.2 d vs 6.3±1.4 d) than children only receiving the rehydration therapy (P<0.05). The prevalence of constipation of children in the IG (3.1%) was markedly lower (P<0.05) than that of children in the CG (13.3%) after treatment. In conclusion, the mixture of three probiotic strains given to children aged 1-3 years resulted in shorter durations of diarrhoea and hospitalisation and a higher percentage of improved children.

Distribution and potential risk assessment of antibiotic pollution in the main drinking water sources of Nanjing, China

The distribution character of 41 antibiotics belonging to 6 groups, sulfonamides (SAs), quinolones (QUs), tetracyclines (TCs), macrolides (MLs), penicillins (PLs), and chloramphenicol (CHL), was investigated in drinking water sources of Nanjing during 2017-2019. MLs (42.98%) were the most abundant category, followed by SAs (25.94%) and QUs (22.52%). The dominant antibiotic was ofloxacin (OFX) in Dec. 2017 (average concentration, 3.14 ng/L; range, ND-35.20 ng/L) and Nov. 2018 (2.16 ng/L, ND-12.26 ng/L), and sulfadiazine (SDZ) in Mar. 2019 (16.37 ng/L, ND-25.90 ng/L). For Dec. 2017, the total concentrations in Zhongshan Waterworks (S15) and Jinniushan Reservoir (S16) were significantly higher than the other sampling sites, which may be attributed to point source pollution. The ecological and human risk of the main antibiotics was assessed by risk quotients (RQs) and target hazard quotient (THQ), respectively. Most of the RQ values were below 0.1, except enrofloxacin (ERX, 0.11) and enoxacin (ENX, 0.62) in Dec. 2017, lomefloxacin (LOM, 0.14) in Nov. 2018, and LOM (0.28) and ERX (0.10) in Mar. 2019. This indicated that the risk of the target antibiotics to aquatic organisms in the 3 years was moderate or low level. Meanwhile, results of the THQ values showed that antibiotic exposure caused no risk to human health. This research provides scientific information for antibiotic pollution control and enriches environmental monitoring data in the drinking water sources.

Transgenerational reproductive and developmental toxicity of tebuconazole in Caenorhabditis elegans

The transgenerational reproductive and developmental toxicity of tebuconazole (TEB) in Caenorhabditis elegans was investigated over five generations (P0 - F4). Only parental C.elegans (P0) were exposed to TEB (0, 0.01, 0.1, 1, and 10 μg/L) for 24 h and the subsequent offspring (F1-F4) were grown under TEB-free conditions. TEB exposure caused dose-dependent reproductive defects and developmental impairments in C.elegans. In the P0 generation reproductive defects were observed such as: reduced brood size and embryo hatchability, prolonged generation time, retarded gonadal development, and slower germline proliferation, even at 0.01 μg/L, together with developmental toxicity with significant reduced body length and narrowed body width at 10 μg/L. Additionally, the brood size significantly reduced in F2, which began to recover from F3, but was still lower than the control in F4. The proportion of abnormalities increased significantly in F2 and reduced from F3, but was still higher than the control, suggesting that TEB could have cumulative potential and be passed to offspring through parental exposure. Furthermore, exposure to TEB (10 μg/L) in P0 significantly reduced the body length in F1, which began to recover from F2, and was the same level as the control in F4. There was a concentration-dependent increase in body width in F1-F4, with a significant increase only observed in F1 at 10 μg/L. Thus, parental exposure to TEB induced transgenerational defects in both reproduction and development, emphasizing the significance of considering bio-toxicity over multiple generations to conduct accurate assessment of environmental risks of toxicants.

Serum Trace Elements in Patients With Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

Polycystic ovary syndrome (PCOS) is reported to be associated with certain trace elements. However, previous data are inconsistent and potentially biased due to small sample sizes. The potential utility of trace element levels for screening of PCOS remains to be established. The aim of this meta-analysis was to investigate the potential relationships between PCOS and serum levels of zinc (Zn), copper (Cu), magnesium (Mg), iron (Fe) and ferritin. We carried out a literature search of PubMed, EMBASE, and Web of Science for relevant cross-sectional/case-control studies published prior to October 2019. Random-effect models were used to estimate the overall standard mean differences (SMDs) between PCOS and healthy control subjects. The screening value of potential microelement biomarkers for PCOS was assessed using the receiver operating characteristic (ROC) curve. Twenty-one studies featuring 2,173 women with PCOS and 1,897 healthy women were selected for analysis. Our results showed that Cu and ferritin levels were significantly higher in women with PCOS than healthy controls, with SMDs of 0.52 [95% confidence interval (CI): 0.38-0.67, I² = 47.6%] and 1.05 (95% CI: 0.25-1.86, I² = 97.0%), respectively. The serum ferritin concentration was distinguished as a potential biomarker for PCOS based on the high area under ROC curve value of 0.71 (95% CI: 0.57-0.86). Although we did not identify a statistical association between serum Zn concentration and PCOS overall, the concentration of Zn in PCOS women with insulin resistance (IR) was lower than that in healthy women (SMD = -0.89, 95% CI: -1.73 to -0.06). Furthermore, the concentrations of Mg (SMD = 0.31, 95% CI: -0.32-0.94, I² = 95.4%) and Fe (SMD = -0.59, 95% CI: -1.29-0.12, I² = 97.2%) were not statistically significant between the PCOS and control groups. We generated hypothetical pathways for associations among serum Cu, ferritin and PCOS. The serum concentrations of both Cu and ferritin were significantly higher in women with PCOS, and ferritin was identified as a potential early indicator for PCOS screening. Further studies are essential to determine the specific underlying mechanisms.

Effects of long-term 4-nonylphenol dietary exposure on reproductive ability of Japanese quails (Coturnix japonica)

As an endocrine disruptor, 4-nonylphenol (4-NP) is widespread in the environment. Here, we investigated the effect of long-term 4-NP dietary exposure on Japanese quails (Coturnix japonica). A total of 72 quails were evenly divided into 24 cages (12 cages for the reproductive toxicity study and 12 cages for the histopathology study, with one male quail and two female quails in each cage) and fed with various doses of 4-NP in diet. The body weight in quails administered with 4-NP was significantly decreased (P < 0.05) in a time- and dose-dependent manner. The egg fertilization rate significantly decreased (P < 0.05) in all treated groups, which was 91.4%, 86.5%, 85.4%, and 86.2% in the control group, 10 mg·kg^-1, 20 mg·kg^-1, and 50 mg·kg^-1 treatment groups, respectively. Moreover, the hatching rate was also significantly decreased (P < 0.05) in the 50 mg·kg^-1 treatment group compared with the control group. Furthermore, the 14-day survival rate of young quails was significantly decreased (P < 0.05) in all treated groups, which was 98.0%, 91.1%, 89.8%, and 86.8% in the control group, 10 mg·kg^-1, 20 mg·kg^-1, and 50 mg·kg^-1 treatment groups, respectively. Damaged spermatogenesis in male quails was found in all treated groups. In conclusion, oral administration of 4-NP impaired the gonads of male quails, leading to reproduction performance damage of Japanese quails.

Global transcriptome analysis to identify critical genes involved in the pathology of osteoarthritis

Objectives

The aim of this study was to identify key pathological genes in osteoarthritis (OA).

Methods

We searched and downloaded mRNA expression data from the Gene Expression Omnibus database to identify differentially expressed genes (DEGs) of joint synovial tissues from OA and normal individuals. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analyses were used to assess the function of identified DEGs. The protein-protein interaction (PPI) network and transcriptional factors (TFs) regulatory network were used to further explore the function of identified DEGs. The quantitative real-time polymerase chain reaction (qRT-PCR) was applied to validate the result of bioinformatics analysis. Electronic validation was performed to verify the expression of selected DEGs. The diagnosis value of identified DEGs was accessed by receiver operating characteristic (ROC) analysis.

Results

A total of 1085 DEGs were identified. KEGG pathway analysis displayed that Wnt was a significantly enriched signalling pathway. Some hub genes with high interactions such as USP46, CPVL, FKBP5, FOSL2, GADD45B, PTGS1, and ZNF423 were identified in the PPI and TFs network. The results of qRT-PCR showed that GADD45B, ADAMTS1, and TFAM were down-regulated in joint synovial tissues of OA, which was consistent with the bioinformatics analysis. The expression levels of USP46, CPVL, FOSL2, and PTGS1 in electronic validation were compatible with the bio-informatics result. CPVL and TFAM had a potential diagnostic value for OA based on the ROC analysis.

Conclusion

The deregulated genes including USP46, CPVL, FKBP5, FOSL2, GADD45B, PTGS1, ZNF423, ADAMTS1, and TFAM might be involved in the pathology of OA.

Cite this article: X. Zhang, Y. Bu, B. Zhu, Q. Zhao, Z. Lv, B. Li, J. Liu. Global transcriptome analysis to identify critical genes involved in the pathology of osteoarthritis. Bone Joint Res 2018;7:298–307. DOI: 10.1302/2046-3758.74.BJR-2017-0245.R1.

Effects of 4-nonylphenol in drinking water on the reproductive capacity of Japanese quails (Coturnix japonica)

4-nonylphenol (4-NP), a major degradation product of Nonylphenol ethoxylates (NPEOs), is widespread in environment. In this study, the effects of long-term 4-NP exposure in drinking water on Japanese quails (Coturnix japonica) were investigated. A total of 45 quails were evenly divided into 15 groups and administrated with various doses (0.1 μg L^-1, 1.0 μg L^-1, 10 μg L^-1 and 100 μg L^-1, which reflected the environmental concentrations of 4-NP) of 4-NP in drinking water. The results showed that 4-NP in drinking water had no effect on quails' food intake, but significantly decreased the quails' body weights (P < 0.05) in a time- and dose-dependent manner. The egg fertilization rates were also significantly decreased (P < 0.05) in all treatment groups. Moreover, the hatchability was significantly reduced (P < 0.05) in 10 μg L^-1 and 100 μg L^-1 groups, and the 14 d survival rates of young quails were significantly decreased (P < 0.05) in 1.0 μg L^-1, 10 μg L^-1 and 100 μg L^-1 groups. Damaged spermatogenesis in male quails was observed in all treatment groups. Therefore, administration of 4-NP in drinking water impaired the reproductive ability of Japanese quails, and led to pathological lesions in the male gonads.

Leaching of Conductive Species: Implications to Measurements of Electrical Resistivity

Electrical tests have been used to characterize the microstructure of porous materials, the measured electrical response being determined by the contribution of the microstructure (porosity and tortuosity) and the electrical properties of the solution (conductivity of the pore solution) inside the pores of the material. This study has shown how differences in concentration between the pore solution (i.e., the solution in the pores) and the storage solution surrounding the test specimen leads to significant transport (leaching) of the conductive ionic species between the pore solution and the storage solution. Leaching influences the resistivity of the pore solution, thereby influencing electrical measurements on the bulk material from either a surface or uniaxial bulk resistance test. This paper has three main conclusions: 1.) Leaching of conductive species does occur with concentration gradients and that a diffusion based approach can be used to estimate the time scale associated with this change. 2.) Leaching of ions in the pore solution can influence resistivity measurements, and the ratio of surface to uniaxial resistivity can be used as a method to assess the presence of leaching and 3.) An estimation of the magnitude of leaching for standardized tests of cementitious materials.

Metagenomic analysis of bacterial community composition and antibiotic resistance genes in a wastewater treatment plant and its receiving surface water

The presence of pathogenic bacteria and the dissemination of antibiotic resistance genes (ARGs) may pose big risks to the rivers that receive the effluent from municipal wastewater treatment plants (WWTPs). In this study, we investigated the changes of bacterial community and ARGs along treatment processes of one WWTP, and examined the effects of the effluent discharge on the bacterial community and ARGs in the receiving river. Pyrosequencing was applied to reveal bacterial community composition including potential bacterial pathogen, and Illumina high-throughput sequencing was used for profiling ARGs. The results showed that the WWTP had good removal efficiency on potential pathogenic bacteria (especially Arcobacter butzleri) and ARGs. Moreover, the bacterial communities of downstream and upstream of the river showed no significant difference. However, the increase in the abundance of potential pathogens and ARGs at effluent outfall was observed, indicating that WWTP effluent might contribute to the dissemination of potential pathogenic bacteria and ARGs in the receiving river.

Silencing NFBD1/MDC1 enhances the radiosensitivity of human nasopharyngeal cancer CNE1 cells and results in tumor growth inhibition

NFBD1 functions in cell cycle checkpoint activation and DNA repair following ionizing radiation (IR). In this study, we defined the NFBD1 as a tractable molecular target to radiosensitize nasopharyngeal carcinoma (NPC) cells. Silencing NFBD1 using lentivirus-mediated shRNA-sensitized NPC cells to radiation in a dose-dependent manner, increasing apoptotic cell death, decreasing clonogenic survival and delaying DNA damage repair. Furthermore, downregulation of NFBD1 inhibited the amplification of the IR-induced DNA damage signal, and failed to accumulate and retain DNA damage-response proteins at the DNA damage sites, which leaded to defective checkpoint activation following DNA damage. We also implicated the involvement of NFBD1 in IR-induced Rad51 and DNA-dependent protein kinase catalytic subunit foci formation. Xenografts models in nude mice showed that silencing NFBD1 significantly enhanced the antitumor activity of IR, leading to tumor growth inhibition of the combination therapy. Our studies suggested that a combination of gene therapy and radiation therapy may be an effective strategy for human NPC treatment.

Lower serum fibroblast activation protein shows promise in the exclusion of clinically significant liver fibrosis due to non-alcoholic fatty liver disease in diabetes and obesity

Non-alcoholic fatty liver disease (NAFLD) is common in diabetes and obesity but few have clinically significant liver fibrosis. Improved risk-assessment is needed as the commonly used clinical-risk algorithm, the NAFLD fibrosis score (NFS), is often inconclusive.

AIMS

To determine whether circulating fibroblast activation protein (cFAP), which is elevated in cirrhosis, has value in excluding significant fibrosis, particularly combined with NFS.

METHODS

cFAP was measured in 106 with type 2 diabetes who had transient elastography (Cohort 1) and 146 with morbid obesity who had liver biopsy (Cohort 2).

RESULTS

In Cohort 1, cFAP (per SD) independently associated with median liver stiffness (LSM) ≥ 10.3 kPa with OR of 2.0 (95% CI 1.2-3.4), p=0.006. There was 0.12 OR (95% CI 0.03-0.61) of LSM ≥ 10.3 kPa for those in the lowest compared with the highest FAP tertile (p=0.010). FAP levels below 730 pmol AMC/min/mL had 95% NPV for LSM ≥ 10.3 kPa and reclassified 41% of 64 subjects from NFS 'indeterminate-risk' to 'low-risk'. In Cohort 2, cFAP (per SD), associated with 1.7 fold (95% CI 1.1-2.8) increased odds of significant fibrosis (F ≥ 2), p=0.021, and low cFAP reclassified 49% of 73 subjects from 'indeterminate-risk' to 'low-risk'.

CONCLUSIONS

Lower cFAP, when combined with NFS, may have clinical utility in excluding significant fibrosis in diabetes and obesity.

Oxidative stress and histopathological alterations in liver of Cyprinus carpio L. induced by intraperitoneal injection of microcystin-LR

Microcystins (MCs) are a group of cyclic heptapeptide hepatotoxic peptides produced by cyanobacteria. Microcystins-LR (MC-LR) can inhibit the activities of protein phosphatase type 1 and type 2A (PP1 and PP2A) and induce excessive production of reactive oxygen species (ROS). However, the detailed toxicological mechanism involving oxidative stress in carp (Cyprinus carpio L.) remains largely unclear. In our present study, the effects of sublethal intraperitoneal doses of MC-LR on the oxidative stress and pathological changes in carp liver were investigated. No significant changes of xanthine oxidase were observed, suggesting it might not contribute to over-production of ROS in the liver of fish during 48 h exposure to sublethal intraperitoneal doses of MC-LR. Superoxide dismutase activity in the 50 μg kg(-1) group was significantly induced at 1-24 h. The strongest inhibition of the catalase activity was shown at 48 h after 120 μg kg(-1) MC-LR exposure, with an inhibition rate of 33.7% compared to the control group. In general, a significant depletion of intracellular reduced glutathione was found at 5-12 h after 50 and 120 μg kg(-1) MC-LR exposure, which was mainly due to the conjugation reaction to MC-LR catalyzed by glutathione-S-transferase and its subsequent excretion. Oxidative damages induced by MC-LR were evidenced by the significant elevation in malondialdehyde levels. In addition, a series of histopathological alterations in fish livers were observed, and the most severe hepatic injuries were found at 5-12 h, which could contribute to the efflux of intracellular GSH. Our study further supports the important role of oxidative stress involved in MC-LR induced liver injury in aquatic organisms.

The ecological roles of Bacillus thuringiensis within phyllosphere environments

Bacillus thuringiensis (Bt) is one of the most used bio-control agents to control plant insects, but little is known about its effect on the microbial population and communities on plant leaves. With the culture dependent method, it has been observed that the dynamics of Bt within the phyllosphere varied dependent on both the doses of Bt sprayed on the leaves and the plant species, however, Bt's population size kept stable at about 1000 cfu g(-1) after 15 d since inoculation. By comparing the bacterial abundances and community structures within the phyllosphere of three plant species, we confirmed that Bt at the doses of 1.5×10(7) and 1.5×10(9) cfu mL(-1) respectively did not significantly influence the natural bacterial population size on the leaf surfaces based on culture dependent assay. However, based on culture independent denaturing gradient gel electrophoresis (DGGE), Shannon-Wiener index (H') and Unweighted Pair Group Method with Arithmetic Mean (UPGMA) analysis, Bt has a significant influence on the bacterial communities within the phyllosphere of amaranth and cotton, but not rice. These results indicate that Bt exhibits different behaviors and ecological roles on the microbial diversity within the phyllosphere, and its environmental safety has to be concerned and evaluated in the future.

Environmental fate of tetracycline resistance genes originating from swine feedlots in river water

Tetracyclines are antibiotics commonly used in swine farms to treat disease and promote growth. However, there are growing concerns regarding the discharge of animal feces into the environment owing to the potential for development and dissemination of tetracycline resistance genes (TRGs). In this study, farming wastewater from one Chinese swine farm as well as river water from seven locations downstream of the farm was sampled. Polymerase chain reaction (PCR) showed that 12 TRGs, including six efflux pump genes (tet(B), tet(C), tet(D), tet(E), tet(G) and tet(L)), five ribosomal protection proteins (RPPs) genes (tet(O), tet(M), tet(Q), tet(W) and tet(S)), and one enzymatic modification gene (tet(X)), were present in all wastewater and river water samples. Quantitative real-time PCR (qPCR) showed that the abundance of tet(C), tet(X), tet(O), tet(M), tet(Q) and tet(W) decreased with downstream flow. Among the detected TRGs, tet(C) had the highest abundance, ranging from 459.5 copies/16S rRNA gene copies in wastewater to 33.8 copies/16S rRNA gene copies in river water samples collected from the last location. Furthermore, pig-specific Bacteroidales 16S rRNA genetic marker was quantified by qPCR to determine the level of fecal pollution in the river water. Bivariate correlation analysis confirmed that the total relative abundance of the six TRGs was significantly correlated with the level of swine feces in the aquatic environment (R(2) = 0.63, P < 0.05), suggesting that swine feces mainly contributed to the spread of TRGs in the river water.

LPCVD of InN on GaAs(110) Using HN3 and TMIn: Comparison with Si(100) Results

Low-pressure chemical vapor deposition (LPCVD) of InN and laser-assisted LPCVD on GaAs(110) and Si(100) using HN3 and trimethyl indium (TMIn) has been studied with XPS, UPS and SEM. Without 308-nm excimer laser irradiation, InN film was built on the GaAs but not on Si surface under the present low-pressure conditions. When the photon beam was introduced, InN films with In:N atomic ratio of 1.0±0.1 and a thickness of more than 20 Å (the limit of the electron escaping depth for the In3d X-ray photoelectrons) were formed on Si(100) surface. In both cases, the formation of surface nitrides at the initial film growth processes was clearly indicated in the XPS spectra. The He(II) UP spectra taken from InN films on GaAs and Si are nearly identical and agree well with the result of a pseudo-potential calculation for the InN valence band. The corresponding SEM pictures showed smooth InN films on GaAs(110), while grains with diameter of ∼100 nm were observed for InN on Si(100).