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Single particle-inductively coupled plasma mass spectrometry (SP-ICP-MS) is a powerful tool for size-characterization of metal-containing nanoparticles (MCNs) at environmentally relevant concentrations, however, coexisting dissolved metal ions greatly interfere with the accuracy of particle size analysis. The purpose of this study is to develop an online technique that couples hollow fiber ultrafiltration (HFUF) with SP-ICP-MS to improve the accuracy and size detection limit of MCNs by removing metal ions from suspensions of MCNs. Through systematic optimization of conditions including the type and concentration of surfactant and complexing agent, carrier pH, and ion cleaning time, HFUF completely removes metal ions but retains the MCNs in suspension. The optimal conditions include using a mixture of 0.05 vol.% FL-70 and 0.5 mmol/L Na

Introduction: Chronic rhinosinusitis with nasal polyps (CRSwNPs) in China is characterized by a mixed eosinophilic-neutrophilic inflammation, linking to a more heterogeneous clinical phenotype. However, the relationship between eosinophilic and neutrophilic inflammation in Chinese patients with CRSwNP remains largely unknown. We aimed to further characterize the correlation between neutrophils with eosinophils in relation to clinical characters and disease control status after endoscopic sinus surgery (ESS). Methods: A total of 242 patients were recruited and stratified based on tissue (≥10%) eosinophilia and (≥20/per high-power field) neutrophilia. Clinical characteristics and disease control status were compared between subgroups. Associations between tissue eosinophils and neutrophils were analyzed. Results: The uncontrolled patients accounted for 41.3%, 41.3%, 17.1%, and 22.2% in subjects with concomitant tissue eosinophilia and neutrophilia (EN-high), isolated eosinophilia (E-high), isolated neutrophilia (N-high), and no eosinophilia and neutrophilia (EN-low), respectively. Positive correlations between tissue eosinophils and neutrophils were observed in patients with CRSwNP as well as in EN-high and N-high subgroups but not in E-high and EN-low subgroups. The EN-high subgroup had higher tissue eosinophil numbers than the other three subgroups. Both EN-high and E-high subgroups had higher rates of uncontrolled subjects than the N-high and EN-low subgroups; however, there was no difference in the rate of uncontrolled subjects between EN-high and E-high subgroups and between N-high and EN-low subgroups. Conclusion: Tissue neutrophils might have a potential interaction and mutual promotion effect with eosinophils in CRSwNP. However, tissue neutrophilia would not pose significant risk for poor disease control after ESS. Further larger, prospective studies are needed to confirm our findings.

High tissue and blood eosinophils are linked to poor treatment outcome in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). However, the difference between the patients with different level of blood or tissue eosinophilia in relation to disease control is still lacking.This study aimed to characterize patients with CRSwNP with intensely high eosinophil level.A retrospective study of CRSwNP patients underwent endoscopic sinus surgery was conducted. The patients were subdivided with various cut-off values of blood and tissue eosinophils. Tissue eosinophils of ≥50% and 10%-20% were defined as intensely high tissue eosinophils (IH-tissue-eos) and high tissue eosinophils (H-tissue-eos), respectively. Blood eosinophils of ≥0.6 × 10A total of 302 patients were enrolled. There was a trend toward a higher rate of uncontrolled disease when the patients subdivided by blood eosinophil cut-off values ranged from 0.1 × 10CRSwNP patients with IH-blood-eos (≥0.6 × 10

Background Considering the inevitability for humans to be frequently exposed to nanoparticles (NPs), understanding the biosafety of NPs is important for rational usage. As an important part of the innate immune system, macrophages are widely distributed in vital tissues and are also a dominant cell type that engulfs particles. Mitochondria are one of the most sensitive organelles when macrophages are exposed to NPs. However, previous studies have mainly reported the mitochondrial response upon high-dose NP treatment. Herein, with gold nanoparticles (AuNPs) as a model, we investigated the mitochondrial alterations induced by NPs at a sublethal concentration. Results At a similar internal exposure dose, different AuNPs showed distinct degrees of effects on mitochondrial alterations, including reduced tubular mitochondria, damaged mitochondria, increased reactive oxygen species, and decreased adenosine triphosphate. Cluster analysis, two-way ANOVA, and multiple linear regression suggested that the surface properties of AuNPs were the dominant determinants of the mitochondrial response. Based on the correlation analysis, the mitochondrial response was increased with the change in zeta potential from negative to positive. The alterations in mitochondrial respiratory chain proteins indicated that complex V was an indicator of the mitochondrial response to low-dose NPs. Conclusion Our current study suggests potential hazards of modified AuNPs on mitochondria even under sublethal dose, indicates the possibility of surface modification in biocompatibility improvement, and provides a new way to better evaluation of nanomaterials biosafety.

Biomonitoring is an effective way to assess the effects of pollutants on marine ecosystems. As an important fishing region in China, the Chinese Bohai Sea has been contaminated with heavy metals, posing great risks to seafood safety and human health. Herein, the spatiotemporal variations in the concentrations of seven heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) in 11 species of mollusks (658 samples) collected from the Chinese Bohai Sea were studied during 2006-2016. The concentrations of Cr, As, Cd, and Pb in approximately 41%, 100%, 71%, and 18% of the sampled mollusks exceeded the maximum permissible levels in aquatic products set by China, indicating that the mollusks were contaminated with varied concentrations of heavy metals. Except for slight fluctuations, no significant temporal variations were observed during the sampling period, suggesting a relatively stable status of these metals. Cluster analysis showed that oyster had higher bioaccumulation potential for Zn and Cu, whereas Mactra veneriformis, Rapana venosa, Meretrix meretrix, Chlamys farreri, and Mya arenaria had higher bioaccumulation potentials for Cr, As, Ni, Cd, and Pb, respectively. These findings are useful for biomonitoring and developing guidelines for seafood consumption in coastal regions. Significant relationships were observed between heavy metal concentrations in mollusks and socioeconomic indices (gross domestic product, per capita gross domestic product, and population amount), suggesting the effects of anthropogenic activities on heavy metal contamination. Our study established a good model to evaluate the risks of heavy metals and provided a sound scientific basis for controlling seafood safety in coastal regions.

PURPOSE To evaluate and compare the effectiveness of endoscopic trans-ethmosphenoid optic canal decompression (ETOCD) and steroid pulse therapy (SPT) for indirect traumatic optic neuropathy (ITON). DESIGN Prospective interventional case series. METHODS Total 140 monocular ITON patients from January 2017 to June 2019 were recruited, including 100 patients received ETOCD (56 patients received ETOCD only and 44 patients received ETOCD combined with SPT before surgery), and 40 patients received SPT only. Their visual acuity (VA) and visual evoked potential (VEP) were analysed before and after treatments. Initial VA, lag time, causes of injuries and age were analysed for evaluating prognosis of treatment. RESULTS In contrast with patients received SPT only (15/40 = 38%), the effective rate of patients received ETOCD only and patients received ETOCD combined with SPT were both significantly better (46/56 = 82%, p

With developments in multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS), applications of metal stable isotopes received increasing attentions in the studies of source and fate of heavy metals in the environment. In light of the rapid progresses in this emerging field, we attempted to review the recent findings comprehensively in a way that environmental scientists can easily read. This review started with an introduction of basic terminologies in isotope geochemistry, followed with detailed descriptions of instrumentation and analytical procedures, and finally focused on the cases of three typical metal stable isotopes (Ag, Hg and Zn) to illustrate how they were applied to address environmental issues. Additionally, future perspectives on the applicability, opportunities, and limitations of metal stable isotope techniques as novel approaches in advancing environmental chemistry were discussed.

Tumor necrosis factor receptor-associated factor 6 (TRAF6) has been found to be involved in carcinogenesis in multiple cancers. However, the precise role of TRAF6 in cancer has not been extensively investigated and remains largely unknown. In this study, we aimed to investigate the biological function of TRAF6 and its underlying molecular mechanisms in cancer. A positive correlation between poor tumor differentiation and TRAF6 expression status was observed in both oral cancer and breast cancer. Overexpression of TRAF6 promoted proliferation, migration, and G0 /G1 to S phase transition in tumor cells. Tumor necrosis factor receptor-associated factor 6-mediated AKT ubiquitination and subsequent phosphorylation played an essential role in the control of tumor cell malignant behavior. In vivo treatment with TRAF6, but not the E3 ligase deficient TRAF6 mutant, facilitated tumor growth. Our findings indicate that TRAF6 contributes to malignant behavior of human cancers through promoting AKT ubiquitination and phosphorylation. Therefore, TRAF6 could serve as a therapeutic target in cancers.

Evidences showed improvements in clinical asthma outcomes following endoscopic sinus surgery (ESS) in chronic rhinosinusitis (CRS) patients with asthma. However, pulmonary function benefits have remained controversial up to date. The goal of this study was to conduct a systematic review and meta-analysis to investigate the effects of ESS on pulmonary function tests in CRS patients with asthma. Pubmed, Embase and Cochrane Library were searched up to March 2018 to obtain relevant studies. The researches that evaluated the effects of ESS on pulmonary function in CRS patients with asthma and had at least one parameter of pulmonary function tests before and after surgery were included in the study. A total of 13 studies containing 421 patients satisfied the eligibility after judgment by 2 reviewers. These included three RCTs and ten case series. The heterogeneity in parameters of spirometry and difference in data presented forms across studies along with the lack of standard deviation of some data make it difficult to synthesize results. If data were unavailable for meta-analyses, descriptive statistics were used to report study outcomes. After qualitative and quantitative analysis, the weighted mean change after ESS in forced expiratory flow between 25% and 75% of vital capacity (FEF25–75%) was 0.21 L/s (95% CI 0.12–0.30); eight of ten studies supported that forced expiratory volume at 1 s (FEV1) improved after ESS; five of six studies supported that peak expiratory flow (PEF) improved after ESS. However, strength of evidence is generally low to insufficient. A generally low-quality evidence supports the association between ESS and improvements in FEF25–75%, FEV1 and PEF. A few studies met inclusion criteria for meta-analysis, which indicates the need for more high-quality studies to determine the effect of ESS.

Metalloproteins play crucial and distinct roles in a variety of biological processes that rely heavily on the metal ions and various proteins. However, there is still a lack of method for rapid analysis of metalloproteins in complex samples, especially in salt-rich matrices. In this study, a sensitive method for separation and determination of metalloproteins in salt-rich matrices was developed based on the size exclusion chromatography coupled with inductively coupled plasma-mass spectrometry (SEC-ICP-MS), combining with the high matrix introduction (HMI) mode, which is quite essential for biological system. The separation conditions of the SEC-ICP-MS system were optimized by using four iodine labeled proteins with different molecular weights, including bovine serum albumin (BSA, 66.0 kDa), ovalbumin (OVA, 44.0 kDa), carbonic anhydrase (CA, 29.0 kDa) and ribonuclease A (RA, 13.7 kDa). After optimization, four iodine labeled proteins and iodine ions were successfully separated within 30 min by using 10 mmol/L HEPES and 40 mmol/L Na

Although the abiotic and biotic transformation/degradation (T/D) processes of tetrabromobisphenol A (TBBPA) have been widely investigated in model experiments, few reviews have focused on these processes along with their metabolites or degradation products. In this paper, we summarize the current knowledge on the T/D of TBBPA and its derivatives, including abiotic and biotic T/D strategies/conditions, mechanisms, metabolites and environmental occurrences. Various treatments, such as pyrolysis, photolysis, chemical reactions and biotransformation, have been employed to study the metabolic mechanism of TBBPA and its derivatives and to remediate associated contaminated environments. To date, more than 100 degradation products and metabolites have been identified, dominated by less brominated compounds such as bisphenol A, 2,6-dibromo-4-isopropylphenol, 2,6-dibromo-4-hydroxyl-phenol, 2,6-dibromophenol, isopropylene-2,6-dibromophenol, 4-(2-hydroxyisopropyl)-2,6-dibromophenol, etc. It can be concluded that the T/D of TBBPA mainly takes place through debromination and β-scission. In some environmental media and human and animal tissues, brominated metabolites, glucoside and sulfate derivatives are also important T/D products. Here, the T/D products of TBBPA and its derivatives have been most comprehensively presented from the literature in recent 20 years. This review will enhance the understanding of the environmental behaviors of TBBPA-associated brominated flame retardants along with their ecological and health risks.

As an important branch of halogenated bisphenol compounds, the halogenated bisphenol monosubstituted-ether compounds have received a lot of attention in environmental health science because of their toxicity and variability. In this study, a synthetic method for bisphenol monosubstituted-ether byproduct libraries was developed. By using the versatile and efficient method, tetrachlorobisphenol A, tetrabromobisphenol A, and tetrabromobisphenol S monosubstituted alkyl-ether compounds were accessed in 39-82 % yield. Subsequently, the cytotoxicity of 27 compounds were screened using three different cell lines (HepG2, mouse primary astrocytes and Chang liver cells). Compound 2,6-dibromo-4-[3,5-dibromo-4-(2-hydroxyethoxy)benzene-1-sulfonyl]phenol was more toxic than other compounds in various cells, and the sensitivity of this compound to the normal hepatocytes and cancer cells was inconsistent. The compounds 2,6-dichloro-4-(2-{3,5-dichloro-4-[(prop-2-en-1-yl)oxy]phenyl}propan-2-yl)phenol and 2,6-dibromo-4-(2-{3,5-dibromo-4-[(prop-2-en-1-yl)oxy]phenyl}propan-2-yl)phenol were the most toxic to HepG2 cells, and most of the other compounds inhibited cell proliferation. Moreover, typical compounds were also reproductive and developmental toxic to zebrafish embryos at different concentrations. The synthetic byproduct libraries could be used as pure standard compounds and applied in research on environmental behavior and the transformation of halogenated flame retardants.

Eosinophils play a critical role in the pathogenesis of allergic airway inflammation. However, the relative importance of eosinophil activation and pathogenicity in driving the progression of disease severity of allergic rhinitis (AR) remains to be defined. We aimed to assess the relation of activated and pathogenic eosinophils with disease severity of patients with AR. Peripheral blood and nasal samples were collected from patients with mild (n=10) and moderate-severe (n=21) house dust mite AR and healthy control subjects (n=10) recruited prospectively. Expressions of activation and pathogenic markers on eosinophils in the blood and nose were analyzed by flow cytometry. The eosinophilic cation protein- (ECP-) releasing potential and the pro-Th2 function of blood eosinophils were compared between the mild and moderate-severe patients and healthy controls. Our results showed that the numbers of activated (CD44+ and CD69+) and pathogenic (CD101+CD274+) eosinophils in the blood and nose as well as blood eosinophil progenitors were increased in moderate-severe AR compared with the mild patients and healthy controls. In addition, the levels of activated and pathogenic eosinophils in the blood were positively correlated with the total nasal symptom score and serum ECP and eosinophil peroxidase (EPX) levels in patients with AR. Furthermore, the blood eosinophils obtained from the moderate-severe patients exhibited a higher potential of releasing ECP and EPX induced by CCL11 and of promoting Th2 responses than those from the mild patients and healthy controls. In conclusion, patients with moderate-severe AR are characterized by elevated levels of activated and pathogenic eosinophils, which are associated with higher production of ECP, EPX, and IL-4 in the peripheral blood.

Glucocorticoids are the first-line medical treatment for chronic rhinosinusitis with nasal polyps (CRSwNP), whose local metabolism is catalyzed by 11β-HSD1 and 11β-HSD2. This study investigates the role of 11β-HSD1 and 11β-HSD2 on the glucocorticoid response of CRSwNP patients and the pathogenic mechanism of these polyps. Forty-three adult CRSwNP patients were enrolled in this study. We evaluated the endoscopic scores by a nasal polyp grading system before and after treatment. We estimated the response to glucocorticoids by the total endoscopic scores. The logistic regression models and inflammatory characteristic curves were conducted to explore the prediction of the response to glucocorticoid in CRSwNP. The expression of 11β-HSD1 and 11β-HSD2 on human sinonasal epithelial cells (HSECS) was measured under the stimulation of toll-like receptor agonists and dexamethasone. The endoscopic scores in the CRSwNP group declined, the expression of 11β-HSD1/11β-HSD2 increased (r = 0.5276, P = 0.0011), and the cutoff value of the ratio of 11β-HSD1/11β-HSD2 was 0.4654 (sensitivity 79.17%, specificity 88.89%). Dexamethasone induced a decrease in the ratio of 11β-HSD1/11β-HSD2 (P = 0.049) by the stimulation of PGN-BS. We found a strong correlation between the response to glucocorticoids and the ratio of 11β-HSD1/11β-HSD2, which could be used as a marker in predicting the level of tissue response to glucocorticoid therapy in CRSwNP. In addition, PGN-BS could also be a therapeutic target, as it is the negative factor that will decrease the sensitivity of glucocorticoids by reducing the ratio of 11β-HSD1/11β-HSD2.

Background: Cellulose powder (CP) has been reported as a safe and effective complementary treatment for allergic rhinitis (AR). Currently, CP has gained increasing application for clinical management worldwide, particularly in China. However, studies focusing on the effect of CP on normal human nasal epithelial cells (hNECs) and ciliary function are lacking. Here, we aimed to explore the adverse effects of CP on the activity and ciliary function of hNECs. Methods: We biopsied ethmoid sinus or middle turbinate tissues during surgical resection from control subjects who underwent endoscopic sinus surgery for diseases other than AR. Cells were isolated and passaged, followed by differentiation in an air-liquid interface (ALI). Flow cytometry and cell viability test (cell counting kit-8) were performed to detect the cytotoxicity of CP (effects on cell proliferation) on normal hNECs. By using the ALI culture model, we investigated the effects of CP on ciliary beat frequency (CBF). Results: There was a significant reduction in hNEC count at high concentrations of CP (2.5 mg/mL) at days 3 and 7 (both p < 0.05). As the concentration increased, cell death increased progressively from day 3 to day 7. However, these effects were not evident at low concentrations (0.25 mg/mL, p > 0.05). High-dose CP (2.5 mg) significantly reduced the CBF (p < 0.05). At lower concentrations (0.25–2.5 mg/mL), CP initially increased but subsequently reduced the CBF of hNECs compared with control group. Conclusions: Cytotoxicity and the suppression of ciliary beat at high concentrations justify more prudent use of CP for the management of AR.

Selenium (Se) is commonly recognized as a protective element with an antagonistic effect against mercury (Hg) toxicity. However, the mechanisms of this Hg–Se antagonism are complex and remain controversial. To gain insight into the Hg–Se antagonism, a type of unicellular eukaryotic protozoa (Tetrahymena malaccensis, T. malaccensis) was selected and individually or jointly exposed to two Hg and three Se species. We found that Se species showed different toxic effects on the proliferation of T. malaccensis with the toxicity following the order: selenite (Se(IV)) > selenomethionine (SeMeth) > selenate (Se(VI)). The Hg–Se antagonism in Tetrahymena was observed because the joint toxicity significantly decreased under co-exposure to highly toxic dosages of Hg and Se versus individual toxicity. Unlike Se(IV) and Se(VI), non-toxic dosage of SeMeth significantly decreased the Hg toxicity, revealing the influence of the Se species and dosages on the Hg–Se antagonism. Unexpectedly, inorganic divalent Hg (Hg2 +) and monomethylmercury (MeHg) also displayed detoxification towards extremely highly toxic dosages of Se, although their detoxifying efficiency was discrepant. These results suggested mutual Hg–Se detoxification in T. malaccensis, which was highly dependent on the dosages and species of both elements. As compared to other species, SeMeth and MeHg promoted the Hg–Se joint effects to a higher degree. Additionally, the Hg contents decreased for all the Hg–Se co-exposed groups, revealing a sequestering effect of Se towards Hg in T. malaccensis.

BACKGROUND MicroRNA 194 is involved in the differentiation of various types of cells, such as adipose derived stem cells, human embryonic stem cells, and bone marrow mesenchymal stem cells. Previously, we found that miR-194 was highly expressed in the inner ear sensory patch and neurons in mice embryos. However, the role of miR-194 in the development of the inner ear and its underlying mechanism have not been elucidated yet. MATERIAL AND METHODS The expression level of miR-194 has been altered by using antisense morpholino oligonucleotides (MO) and synthesized miRNAs in zebrafish. RESULTS We found that miR-194 was vastly expressed in the inner ear and central nervous system (CNS) in zebrafish. Loss of function of miR-194 could strongly affected the development of zebrafish embryos, including delayed embryonic development, edema of the pericardium, small head, axial deviation, delayed development of inner ear, closer location of two otoliths, delayed fusion of the semicircular canals, and abnormal otolith number in some cases. In addition, the behavior of zebrafish was also adversely affected with impaired balance and biased swimming route. Misexpression of miR-194 could strongly affected the development and differentiation of spiral ganglion neuron (SGN) in inner ear through Fgf4 in vitro. Similar results have also been observed that the overexpression and knockdown of miR-194 strongly disturbed the development and differentiation of the sensory patches and Statoacoustic ganglion (SAG) through Fgf4 in zebrafish in vivo. Our results indicated that miR-194 may regulate the development and differentiation of sensory patches and SAG through Fgf4. CONCLUSIONS Our data revealed a vital role of miR-194 in regulating the development and differentiation of the inner ear.

Polychloro-1,3-butadienes (polyCBDs) are attracting increasing concern due to their high toxicity. However, research on multiple polyCBDs in aquatic biota is still extremely limited. In this study, a sensitive method for simultaneous determination of nine polyCBD (Cl4–Cl6) congeners, including six tetrachlorobutadiene (TeCBD) isomers, two pentachlorobutadiene (PeCBD) isomers, and hexachlorobutadiene (HCBD), in shellfish was developed based on accelerated solvent extraction (ASE), solid-phase extraction (SPE) clean-up and gas chromatography-triple quadrupole mass spectrometry (GC-QqQ-MS/MS). Low method limits of detection (MDLs) in the range 0.03–0.21 ng/g dry weight for target analytes with satisfactory recoveries (47.7 %–70.6 %) were achieved. The valid method was then applied to analyze nine polyCBDs congeners in 42 shellfish and 11 fish samples collected from markets in eight coastal cities, China. Trace HCBD was detected in 14 samples, while TeCBDs and PeCBDs were under the MDLs in all the samples, indicating little contamination of these pollutants in the marketed shellfish and fish in China. Multiple polyCBDs especially TeCBDs and PeCBDs were firstly involved in the proposed method and investigation here, which lay the groundwork for future research on the environmental behavior and exposure risks of polyCBDs in aquatic biotas.

Black phosphorus nanosheets (BPs) have exhibited great potential for various applications including biomedicine, thus their potential side effects and corresponding improvement strategy deserve investigation. Here, in vitro and in vivo biological effects of BPs with and without titanium sulfonate ligand (TiL4) modification are investigated. Comparing to bare BPs, BPs with TiL4 modification (TiL4@BPs) can efficiently escape from macrophages uptake, and reduce the cytotoxicity and proinflammation. When intravenously injected into mice, bare BPs trigger significant inflammatory responses, including an increase in peripheral neutrophils accompanied by elevation of a group of inflammatory cytokines, while TiL4@BPs exhibit no such adverse immune responses. The corresponding mechanisms are also discussed. These findings may not only guide the applications of BPs, but also propose an efficient strategy to further improve the biocompatibility of BPs.

Tetrabromobisphenol A bis(2-hydroxyethyl) ether (TBBPA DHEE), as one of the TBBPA derivatives, is frequently applied as a flame retardant. To date, however, little evidence has been gathered regarding its environmental behavior and fate. This is mainly attributed to the lack of an analytical approach available to measure it. Mass spectrometry cannot determine levels of TBBPA DHEE. LC-MS could not ionize TBBPA DHEE to yield enough fragments, while GC-MS could not be applied for the analysis either, due to the thermal degradation of TBBPA DHEE. We here designed a novel hapten, then conjugated it with a carrier protein and produced a type of polyclonal antibody capable of recognizing TBBPA DHEE. Based on this approach, a sensitive and high-throughput indirect competitive enzyme-linked immunosorbent assay (ELISA) was established. The respective detection limit (LOD, based on 90% B/B0) and IC50 calculated from the standard curve were 0.702 and 9.868 ng/mL for TBBPA DHEE. And the established method showed good tolerance to various matrix interferents. Using our ELISA, we measured the concentrations of these substances from environmental water samples with no pretreatment other than filtration. We found the presence of TBBPA DHEE in environmental water samples collected in Jiangsu province, and the detected concentrations ranging from 1.5 to 7.7 ng/mL. Our proposed method here could be applied to completely and systematically investigate TBBPA DHEE and TBBPA MHEE concentrations in environmental samples.

Blood is the transmission medium for metal contaminants to and from bodily organs; as such, it can provide useful and reliable information about their bio-kinetics as they're distributed throughout the body. Metals can interact with endogenous proteins present in the blood, and these metal-protein complexes often dictate the fates of the introduced metals. The aim of this study was to investigate cadmium-binding protein characteristics in normal human plasma. Cadmium-binding plasma proteins in two different groups: normal human plasma (n = 29), and normal paired maternal and fetal umbilical cord plasmas (n = 3), were analyzed. In order to detect cadmium-binding plasma proteins present in low concentrations, blood plasma samples were first depleted of their two most abundant proteins - albumin and immunoglobulin G. Both the crude and depleted plasma samples were analyzed using column gel electrophoresis in conjunction with Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). One cadmium-binding protein was detected in 11 of 29 normal plasma samples and all three paired maternal and cord plasma samples. This protein was further identified as apolipoprotein A-I by high-resolution mass spectrometry. To the best of our knowledge, this is the first study to reveal cadmium-binding proteins in real human blood plasma, which is extremely critical to our understanding of cadmium transportation and accumulation in human blood.

Quantitating ultra-low concentrations of protein biomarkers is critical for early disease diagnosis and treatment. However, most current point-of-care (POC) assays are limited in sensitivity to meet this clinical need. Herein, we introduce an ultra-sensitive and facile microbubbling digital assay readout method toward POC quantitation of protein biomarkers requiring only bright-field smartphone imaging. Picolitre-sized microwells together with platinum nanoparticle labels enable the discrete “visualization” of protein molecules via immobilized-microbubbling with smartphone. We also use computer vision and machine learning to develop an automated image analysis smartphone application to facilitate accurate and robust counting. Using this method, post-prostatectomy surveillance of prostate specific antigen (PSA) can be achieved with a detection limit of 2.1 fM (0.060 pg/mL), and early pregnancy detection using βhCG with a detection limit of 0.034 mIU/mL (2.84 pg/mL). The results are further validated using clinical serum samples against clinical and research assays. This work provides the proof-of-principle of the microbubbling digital readout as an ultra-sensitive technology with minimal requirement for power and accessories, facilitating future POC applications.

Despite high production and usage of parabens and bisphenols, little is known about their spatiotemporal distribution in the marine environment. In this study, we determined the concentrations of several parabens and their metabolites as well as bisphenol analogues in sediment collected from coastal areas of northern China. All sediment samples, including surface sediment and sediment cores, contained at least one of the parabens analyzed, and the total concentrations of parabens (ΣPBs; sum of six parabens) ranged from 1.37 to 24.2 ng/g dw (geometric mean: 3.30–6.09 g/g dw), which was comparable to or slightly higher than those found for the total concentrations of five detectable bisphenols (ΣBPAs; geometric mean: 2.18–4.61 ng/g dw). 4-hydroxybenzoic acid, a common metabolite of parabens, was found in all samples at concentrations in the range of 6.85–437 ng/g dw, which was one order of magnitude lower than those found for benzoic acid. Methyl-, ethyl-, and propyl-parabens were the predominant paraben analogues, collectively accounting for >88% of ΣPBs. Bisphenol A and bisphenol F were the two major bisphenols, collectively accounting for >86% of ΣBPAs. We also examined vertical profiles in concentrations of target analytes in sediment cores. The sediment core from the Shandong Peninsula showed a gradual increase in the concentrations of several parent and metabolic parabens as well as bisphenols during the past decade. Relatively higher concentrations of parabens and bisphenols were found in sediment cores collected from industrialized areas. Significant positive correlations were found among the concentrations of parabens in sediment, which suggested the existence of similar sources for these compounds. Overall, our findings suggest that the Bohai Sea coast is moderately contaminated with parabens and bisphenols in comparison to other coastal areas in China or elsewhere.

To trace the circulation history of aquatic bioavailable Hg in the Antarctic, the species and isotopic compositions of Hg in sediment, Archaeogastropoda (Agas), Neogastropoda (Ngas), and fish collected from King George Island were studied in detail. Positive mass independent fractionation (MIF) was observed and positively correlated with the percentages of methylmercury (MeHg%) in Agas and Ngas, suggesting an effect of MeHg accumulation during trophic transfer on MIF signatures. However, both the ratios of Δ199Hg/δ202Hg and Δ199Hg/Δ201Hg indicated different circulation histories of Hg in Agas, Ngas, and fish. The microbial methylation in sediment was the primary source of MeHg in Agas and Ngas (Δ199Hg/δ202Hg ∼0, Δ199Hg/Δ201Hg ∼1.00). In contrast, the MeHg in fish (Δ199Hg/δ202Hg = 0.55 ± 0.06, Δ199Hg/Δ201Hg = 1.19 ± 0.17) came from the combined sources of residual MeHg which had sunk from the surface water and microbial-methylated MeHg in sediments, and the bioavailable Hg in the sediments contributed to approximately 44% of the total Hg in fish. Subsequently, the Δ199Hg values of bioavailable MeHg and IHg in sediments were quantitatively calculated, which provided key end-member information for future source apportionment in the Antarctic and other pelagic regions. It was also found that the Hg accumulated in Agas and Ngas had no history of MeHg photo-degradation, indicating that the methylated Hg in benthic zones suffered little photo-degradation and thus presented high bioavailability and environmental risk.

Understanding the distribution and sources of mercury (Hg) in the Tibetan Plateau is of great value to study the long-range transport of Hg. Herein, the total Hg (THg) concentrations and the isotopic compositions of mosses, conifer needles, and surface soils collected from both slopes of the Shergyla Mountain of Tibetan Plateau were analyzed. The contents of THg in samples (except mosses on the eastern slope) were significantly positively correlated with altitude in both the western and eastern slopes, possibly caused by topographic factors. In contrast, Δ199Hg in samples was significantly negatively correlated with altitude. On the basis of Hg isotopic compositions, atmospheric Hg0 uptake was indicated as the primary accumulation pathway of Hg in mosses (Δ199Hg: −0.12 ± 0.09‰, −0.26 – 0.00‰, 1 SD, n = 10) and conifer needles (Δ199Hg: −0.21 ± 0.08‰, −0.36 – −0.11‰, 1 SD, n = 9). Moreover, the contributing fractions of atmospheric Hg0 to Hg in surface soils (Δ199Hg: −0.20 ± 0.07‰, −0.31 – −0.06‰, 1 SD, n = 17) increased with altitude and accounted for an average of 87 ± 9% in atmospheric sources. Due to the special geographic positions and environmental conditions of the Tibetan Plateau, the results of this study were essential for further understanding the long-range transport and global cycling of Hg.

Environmental distribution and concentration of tetrabromobisphenol A bis- (2-hydroxyethyl) ether (TBBPA-DHEE) and tetrabromobisphenol A mono- (hydroxyethyl) ether (TBBPA-MHEE), are obscure due to the lack of available analytical methods. Here two novel immunoassays were established to systematically investigate their distributions in Taizhou, Eastern China. Five monoclonal antibodies against pollutants were generated with two designed haptens through animal immunization. After matched with different coating antigens/antibodies, ELISAs were established (LOD for TBBPA-DHEE, 0.12 ng/mL, based on OVA-M3/mAb-D4G6; LOD for TBBPA-MHEE, 0.79 ng/mL, based on OVA-M3/mAb-D2G6) and applied for investigation of their occurrences at a typical e-waste recycling area after 2-year samples collection, where the total 33 water, 32 soil and 16 biological samples were collected with the highest concentrations of 3.46 ng/mL, 2.76 ng/g (dry weight, dw) and 5.01 ng/g (dw), respectively. Meanwhile, our study also indicated that at the centralizing e-waste recycling sites the serious pollution for both chemicals still existed despite of various efforts. Besides, obvious improvements were observed at an abandoned e-waste recycling region treated and remedied for many years by the local Chinese government. These findings highlight the importance of policy decisions in treatment of pollutants to reduce organic pollutant-related health risks.

Annual air samples were collected at various sites in the Fildes Peninsula, West Antarctica from December 2010 to January 2018 using XAD-2 resin passive air samplers to investigate concentrations, temporal trends and potential sources of persistent organic pollutants (POPs) in Antarctic air. Relatively low concentrations of polychlorinated biphenyls (PCBs) (Σ19PCBs: 1.5–29.7 pg/m3), polybrominated diphenyl ethers (PBDEs) (Σ12PBDEs: 0.2–2.9 pg/m3) and organochlorine pesticides (OCPs) (Σ13OCPs: 101–278 pg/m3) were found in the atmosphere of West Antarctica. PCB-11, BDE-47 and hexachlorobenzene (HCB) were the predominant compounds in the atmosphere. The concentrations of PCBs, HCHs, DDTs and endosulfans were found to show decreasing temporal trends, whereas uniform temporal trends were observed for HCB. The atmospheric half-life values for PCBs, HCHs, DDTs and endosulfans in Antarctic air were estimated for the first time, using regressions of the natural logarithm of the concentrations versus the number of years, obtaining the values of 2.0, 2.0, 2.4 and 1.2 year, respectively. An increasing ratio of α-HCH/γ-HCH indicated long residence time for α-HCH and possible transformation of γ-HCH to α-HCH in the atmosphere. The ratios of p,p'-DDT/p,p'-DDE were mostly lower than unity in this study, which could be attributed to aged sources. It was found that long-range atmospheric transport was still considered to be the main contributing factor to the atmospheric levels of the POPs in West Antarctica whereas the contribution of human activities at the Chinese Great Wall Station was minor. The results of this study give a view on the most recent temporal trends and provide new insights regarding the occurrence of various POPs in the Antarctic atmosphere.

Methylmercury (MeHg) in sediment is difficult to be determined due to its low concentration and binding compounds like sulfide and organic matter. Moreover, wet sediment samples have been suggested to behave differently from certified reference materials in MeHg analysis. Optimal pretreatment procedure for MeHg determination in sediments hasn’t been ascertained and whether the procedure could apply to sediment samples with complex matrix merits further research. This work firstly compared recovery results of five pretreatment procedures for MeHg determination using ERM-CC580. Using the optimal pretreatment procedure, recovery results were analyzed in different sediment samples after manipulation of moisture content, organic matter and acid volatile sulfide. The procedure using CuSO4/HNO3 as leaching solutions and mechanical shaking as extraction method was proved to produce the most satisfactory recovery results (100.67 ± 6.75%, mean ± standard deviation). And when moisture contents varied from 20% to 80%, average recovery results in sediment samples ranged from 100% to 125%. Furthermore, before and after the manipulation of organic matter or acid volatile sulfide, spiking recovery results varied little and were all within acceptable limit (85%~105%). Therefore, the procedure of CuSO4/HNO3-mechanical is proposed as a universal pretreatment method for MeHg determination in sediment samples with various characteristics.

This study aimed to determine the effect of exposure to heavy metals in pregnant women in Beijing, China. We also evaluated the association of these heavy metals with birth weight and length of newborns. We measured the levels of 10 heavy metals, including lead (Pb), titanium (Ti), manganese (Mn), nickel (Ni), cadmium (Cd), chromium (Cr), antimony (Sb), stannum (Sn), vanadium (V), and arsenic (As), in 156 maternal and cord blood pairs. An inductively coupled plasma mass spectrometry method was used for measurement. Pb, As, Ti, Mn, and Sb showed high detection rates (> 50%) in both maternal and cord blood. Fourteen (9%) mothers had blood Pb levels greater than the United States Center for Disease Control allowable threshold limit for children (50 μg/L). In prenatal exposure to these heavy metals, there was no significant association between any heavy metal and birth weight/length. Moreover, we estimated the placental transfer efficiency of each heavy metal, and the median placental transfer efficiency ranged from 49.6% (Ni) to 194% (Mn) (except for Cd and Sn). The level and detection rate of Cd in maternal blood were much higher than that in cord blood, which suggested that Cd had difficulty in passing the placental barrier. Prospective research should focus on the source and risk of heavy metals in non-occupationally exposed pregnant women in Beijing.

Organotin compounds (OTs) are used in a range of industrial products, such as antifouling paints, agricultural pesticides and stabilizers. Owing to potential endocrine-disrupting effects, human exposure to such compounds is a concern. Nevertheless, little is known about the adverse effect of OTs on adrenocortical function in organisms. In this study, the human adrenocortical carcinoma cell (H295R) model was used to investigate effects of OTs on steroidogenesis and potential causes for such endocrine disruption was examined. H295R cells were exposed to several commonly used OTs, including triphenyltin (TPT), tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT), and the production level of steroid hormones were quantified. TPT and TBT decreased the production levels of 17β-estradiol, aldosterone, and cortisol, but increased that of testosterone. Furthermore, the expression levels of ten major steroidogenic genes (HMGR, StAR, CYP11A1, 3βHSD2, CYP17, CYP19A1, CYP21, CYP11B1, CYP11B2, and 17βHSD) were examined and both up-regulation of CYP11B2 and down-regulation of StAR, 3βHSD2, CYP19A1, CYP21 and CYP11B1 by TPT and TBT were observed. Intracellular levels of ATP and cyclic adenosine monophosphate (cAMP) and the activity of adenylate cyclase (AC) decreased in the H295R cells treated with TPT and TBT. No obvious changes in H295R were found with the treatment of DBT and MBT. These results suggest that OTs may stimulate steroidogenesis in vitro via inhibition of cAMP signaling pathway.

The neurotoxic effects of methylmercury (MeHg) have been intensively studied. However, the molecular mechanisms responsible for the neurotoxicity of MeHg are not fully understood. To decipher these mechanisms, proteomic and high-throughput mRNA sequencing (RNA-seq) technique were utilized, comprehensively evaluating the cellular responses of human neuroblastoma SK-N-SH cells to MeHg exposure. Proteomic results revealed that MeHg exposure interfered with RNA splicing via splicesome, along with the known molecular mechanisms of mercury-related neurotoxicity (e.g. oxidative stress, protein folding, immune system processes, and cytoskeletal organization). The effects of MeHg on RNA splicing were further verified using RNA-seq. Compared to control, a total of 658 aberrant RNA alternative splicing (AS) events were observed after MeHg exposure. Proteomics and RNA-seq results also demonstrated that mercury chloride (HgCl2) influenced the expression levels of several RNA splicing related proteins and 676 AS events compared to control. These results suggested that RNA splicing could be a new molecular mechanism involved in MeHg and HgCl2 neurotoxicity.

Serum amyloid A (SAA) was involved in the pathogenesis of glucocorticoid resistance in lung diseases. However, their association with systemic corticosteroid insensitivity in chronic rhinosinusitis with nasal polyps (CRSwNP) patients remains to be assessed. This study enrolled 32 CRSwNP patients to evaluate the association between SAA expression in NP and corticosteroid insensitivity, and the value of polyp SAA level for predicting the response to oral corticosteroids in CRSwNP patients. All patients were given a course of oral prednisone (30 mg daily for 2 weeks) and subdivided into glucocorticoid(GC)-sensitive and -insensitive subgroup according to the change in polyp size scores. The polyp specimens were obtained before and after corticosteroid treatment. SAA levels in polyp tissues were evaluated by enzyme-linked immunosorbent assay and quantitative reverse transcription polymerase chain reaction. Regression analysis was performed to analyze the association between SAA protein levels and corticosteroid insensitivity. 13/32 (40.62%) CRSwNP patients were insensitive to the oral corticosteroid therapy. SAA mRNA and protein levels were significantly increased in GC-insensitive NP compared to those in GC-sensitive NP. Tissue SAA protein levels were positively correlated with tissue neutrophil numbers. Regression analysis revealed tissue SAA levels were significantly correlated with corticosteroid insensitivity (P

Background Herbal remedies predate written history and continue to be used frequently for many common ailments. The essential oil mixture standardized is a phytopharmaceutical with a distillate of a mixture of rectified essential oils of eucalyptus, sweet orange, myrtle, and lemon as active ingredients used to treat respiratory diseases such as bronchitis and rhinosinusitis. We evaluated the pharmacologic effects of a distillate of rectified essential oils standardized on primary human upper respiratory epithelial cultures specifically addressing electrolyte transport, cilia beat frequency (CBF), airway surface liquid (ASL) hydration, and mucus transport velocity. Methods Well-differentiated primary human sinonasal epithelial cultures grown at an air–liquid interface were treated on the apical or basolateral surface with varying concentrations of a distillate of rectified essential oils standardized. Changes in CBF were determined using the Sissons-Ammons Video Analysis system while changes in chloride flux were determined using the fluorescent dye 6-methoxy-N-(3-sulfopropyl)quinolinium. ASL hydration was quantified using Texas red dextran and mucociliary transport velocity was measured using fluorescent microspheres and time lapse photography. Results When applied to the basolateral surface, a distillate of rectified essential oils standardized activated chloride efflux and ciliary beat in a dose-dependent fashion, increasing ASL height and accelerating mucociliary transport velocity. The ancillary apical application of a distillate of rectified essential oils standardized had minimal effects on the CBF. Conclusion Basolateral application of a distillate of rectified essential oils standardized stimulates both chloride efflux and cilia beat frequency resulting in a synergistic effect dramatically augmenting mucociliary transport velocity. These in vitro data support the clinical efficacy of this phytopharmaceutical in respiratory inflammatory disorders.

As the most widely used brominated flame retardants (BFRs), Tetrabromobisphenol-A (TBBPA) as well as its alternative Tetrabromobisphenol-S (TBBPS) and their derivatives have raised wide concerns due to their adverse effects on human health and hence the sensitive detection of those BFRs was urgently needed. Herein, a novel analytical method based on high-performance liquid chromatography (HPLC) coupled with inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) has been developed for the determination of TBBPA/S and their derivatives, including TBBPA-bis(2-hydroxyethyl ether) (TBBPA-BHEE), TBBPA-bis(allylether) (TBBPA-BAE), TBBPA-bis(glycidyl ether) (TBBPA-BGE), TBBPA-bis(2,3-dibromopropyl ether) (TBBPA-BDBPE) and TBBPS-bis(2,3-dibromopropyl ether) (TBBPS-BDBPE) in water samples. After optimization, the TBBPA/S and their derivatives, especially the TBBPA-BAE and TBBPA-BDBPE were simultaneously and sensitively quantified by determination of bromine (m/z=79) by using the ICP-MS. The instrument limits of detection (LODs) for the TBBPA, TBBPA-BHEE, TBBPA-BGE, TBBPA-BAE, TBBPA-BDBPE, TBBPS and TBBPS-BDBPE were determined to be 0.12, 0.14, 0.19, 0.14, 0.12, 0.17 and 0.13μgL-1, respectively, which was close to or much better than the reported methods. The relative standard deviations (RSDs, n=5) of peak area and retention time were better than 2.2% and 0.2% for intra-day analysis, indicating good repeatability and high precision. The proposed method had been successfully applied for the analysis of TBBPA/S and their derivatives in water samples with satisfactory recoveries (67.7%-113%).

Elemental mercury (Hg0) has different behavior in the environment compared to other pollutants due to its unique properties. It can remain in the atmosphere for long periods of time and so can travel long distances. Through air-surface (e.g., vegetation or ocean) exchange (dry deposition), Hg0 can enter terrestrial and aquatic systems where it can be converted into other Hg species. Despite being ubiquitous and playing a key role in Hg biogeochemical cycling, Hg0 behavior in the environment is not well understood. The objective of this review is to provide a better understanding of how the unique physicochemical properties of Hg0 affects its cycling and chemical transformations in different environmental compartments. The first part focuses on the fundamental chemistry of Hg0, addressing why Hg0 is liquid at room temperature and the formation of amalgam, Hg halide, and Hg chalcogenides. The following sections discuss the long-range transport of Hg0 as well as its redistribution in the atmosphere, aquatic and terrestrial systems, in particular, on the sorption/desorption processes that occur in each environmental compartment as well as the involvement of Hg0 in chemical transformation processes driven by photochemical, abiotic, and biotic reactions.

Many paddy fields have been contaminated by mercury (Hg) in mining areas of China. In this study, twenty-six rice cultivars and three Hg contaminated paddy fields in different geographic regions were selected for field trials and aimed to investigate the variations and similarities in total Hg (THg) and methylmercury (MeHg) accumulations in brown rice (seeds) across sites. Our results revealed widescale cultivar variation in THg (13-52 ng g(-1) at Wanshan) and MeHg (3.5-23 ng g(-1)) accumulation and %MeHg (17.7-89%) in seeds. The ability to translocate is an important factor in the levels of THg and MeHg in seed. Cultivar tended to stability in THg accumulation across sites. Some cultivars accumulated lower concentrations of both THg and MeHg in seeds at fields seriously contaminated by Hg. Present results suggest that appropriate cultivar selection is a possible way to reduce THg and MeHg accumulation in seeds of rice grown in Hg-contaminated regions.

The expression and regulation of serum amyloid A (SAA) in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) have not been well documented. This study enrolled 24 CRSwNP patients and 19 controls to evaluate the expression of SAA in polyp tissues in Chinese adult patients and investigate underlying mechanism. The levels of SAA and interleukin (IL)-17A and myeloperoxidase (MPO) in nasal tissues were detected using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. In addition, the mRNA expression of SAA was examined in cultured polyp epithelial cells (PECs) in the presence of various cytokines (IFN-γ, IL-4, IL-5 and IL-17A) using qRT-PCR, and the role of extracellular signal-related kinase (ERK) signalling in SAA expression was evaluated by western blot analysis. We found the levels of SAA, IL-17A and MPO were significantly upregulated in polyp tissues compared with the controls (p < 0.05), and significant correlations between SAA and IL-17A mRNA levels, as well as between SAA and MPO protein levels, were observed in polyp tissues (p < 0.05). In the in vitro culture system, IL-17A was found to significantly increase SAA mRNA expression in PECs via ERK signaling pathway, in a time- and dose-dependent manner (p < 0.05). Our results suggested a regulatory mechanism underlying excessive SAA production in polyp tissues, which might gain more insights into the pathophysiology of CRSwNP in Chinese adult patients.

Background Functional endoscopic sinus surgery (FESS) is considered to be the standard procedure for chronic rhinosinusitis with nasal polyps (CRSwNP). However, for CRSwNP that accompanies asthma, the results are not satisfying. Extensive endoscopic sinus surgery (EESS) aimed at reducing the inflammatory load has been indicated as a viable option for refractory chronic rhinosinusitis. Objective To evaluate the clinical outcomes and safety of EESS (middle turbinate and superior turbinate resection and total ethmoidectomy) for patients with CRSwNP and with asthma. Methods This was a prospective, single-institute cohort study conducted in a tertiary teaching hospital. Patients with CRSwNP and with asthma who were proceeding to surgery were enrolled. There were 23 patients in the EESS group and 24 patients in the FESS group. The preoperative disease severity was evaluated by the visual analog scale (VAS), Lund-Kennedy (L-K) endoscopy score, computed tomography Lund-Mackay score, asthma control test (ACT), and pulmonary function test. Clinical outcomes were comparatively evaluated between the two groups after a 1-year follow-up by using the VAS score, the postoperative endoscopic score (E score), L-K score, ACT score, and pulmonary function test. Results The disease severity (general VAS score, endoscopic L-K score, computed tomography score, ACT score) showed no significant differences between the two groups before surgery (p > 0.05). One year after surgery, both groups achieved significant improvement in the VAS score and endoscopic L-K score. The EESS group showed better improvement in the olfactory VAS score and E score compared with the FESS group (mean [standard deviation] change of olfactory VAS, 6.00 ∓ 3.67 versus 3.30 ∓ 3.44, p = 0.015; mean [standard deviation] E score, 0.31 ∓ 0.18 versus 0.66 ∓ 0.26, p < 0.001). No significant differences were found in the change of general nasal symptom VAS score, other individual VAS scores (nasal congestion, discharge, headache and/or facial pain), L-K score, ACT score, and pulmonary function between the two groups (p > 0.05). Conclusion EESS for patients with CRSwNP and with asthma may help to improve the subjective olfaction and endoscopic appearance.

In this work, superparamagnetic nanoparticle-decorated graphene (MG) sheets were synthesized and used as support for hemimicelles/admicelles for solid-phase extraction (SPE) of different compounds from environmental water samples for the first time. The MG sheets were facilely synthesized by a one-step, one-pot redox reaction between graphene oxide and Fe(II). Due to the large surface area and unique nanosheet morphology, MG served as an excellent nano-scaled support material for hemimicelles and admicelles, exhibiting higher loading capacity than conventional materials and pure Fe₃O₄ nanoparticles. The MG sheets could be negatively or positively charged depending on solution pH, allowing the extraction to be conducted in different modes. In cationic mode, cetyltrimethylammonium bromide (CTAB) was used as micelle-forming reagent, and perfluoroalkyl and polyfluoroalkyl substances (PFASs) and alkylphenols were used as model analytes. In anionic mode, sodium dodecyl sulfate (SDS) was used as micelle-forming reagent and alkyltrimethylammonium salts were selected as analytes. In both modes, the formation processes of hemimicelles/admicelles on MG sheets were studied and the extraction conditions were optimized. For PFASs, the analytical sensitivity was enhanced by 50-113-fold by the extraction, and the method detection limits (MDLs) ranged from 0.15 to 0.50 ng/L. For alkyltrimethylammonium salts, the MDLs were in the range of 1.4-8.0 ng/L. In both modes, good recoveries (56.3-93.9%) and reproducibility (run-to-run RSDs

Background Connexin (Cx) 26 plays a key role in maintaining the integrity of tight junctions. However, the expression and modulation of Cx26 in allergic rhinitis (AR) has not been well understood. Methods We detected the expression of Cx26 in house-dust mite (HDM)–sensitized AR patients and investigated the Cx26 production and modulation in primary human nasal epithelial cells (HNECs) and BEAS-2B cells after treatment with the allergen Der p 1 from Dermatophagoides pteronyssinus. Results We found that the mRNA and protein levels of Cx26 were significantly down-regulated in AR patients compared with the control. Der p 1 was found to induce protease-activated receptor 2 (PAR2) expression and suppress Cx26 production significantly in vitro. PAR2 siRNA was shown to prevent the suppression of Cx26 induced by Der p 1 in BEAS-2B cells. Conclusion The suppression of Cx26 in HDM-sensitized AR patients is related to a PAR2-mediated pathway and might serve during the initiation and maintenance of AR. Targeting the PAR2-mediated Cx26 suppression may be a potential means of preventing allergic sensitization.

Graphene and graphene oxide sheets supported on silica as versatile and high-performance adsorbents for solid-phase extraction

This study investigated total mercury (THg) and methylmercury (MeHg) concentrations in five species of freshwater fish and their associated fish pond sediments collected from 18 freshwater fish ponds around the Pearl River Delta (PRD). The concentrations of THg and MeHg in fish pond surface sediments were 33.1-386 ng g(-1) dry wt and 0.18-1.25 ng g(-1) dry wt, respectively. The age of ponds affected the surface sediment MeHg concentration. The vertical distribution of MeHg in sediment cores showed that MeHg concentrations decreased with increasing depth in the top 10 cm. In addition, a significant correlation was observed between %MeHg and DNA from Desulfovibrionacaea or Desulfobulbus (p