High glucose-induced NCAPD2 upregulation promotes malignant phenotypes and regulates EMT via the Wnt/ß-catenin signaling pathway in HCC.

Diabetes mellitus (DM) is recognized as a risk factor for hepatocellular carcinoma (HCC). High glucose levels have been implicated in inducing epithelial-mesenchymal transition (EMT), contributing to the progression of various cancers. However, the molecular crosstalk remains unclear. This study aimed to elucidate the molecular mechanisms linking DM to HCC. Initially, the expression of NCAPD2 in HCC cells and patients was measured. A series of functional in vitro assays to examine the effects of NCAPD2 on the malignant behaviors and EMT of HCC under high glucose conditions were then conducted. Furthermore, the impacts of NCAPD2 knockdown on HCC proliferation and the ß-catenin pathway were investigated in vivo. In addition, bioinformatics methods were performed to analyze the mechanisms and pathways involving NCAPD2, as well as its association with immune infiltration and drug sensitivity. The findings indicated that NCAPD2 was overexpressed in HCC, particularly in patients with DM, and its aberrant upregulation was linked to poor prognosis. In vitro experiments demonstrated that high glucose upregulated NCAPD2 expression, enhancing proliferation, invasion, and EMT, while knockdown of NCAPD2 reversed these effects. In vivo studies suggested that NCAPD2 knockdown might suppress HCC growth via the ß-catenin pathway. Functional enrichment analysis revealed that NCAPD2 was involved in cell cycle regulation and primarily interacted with NCAPG, SMC4, and NCAPH. Additionally, NCAPD2 was positively correlated with EMT and the Wnt/ß-catenin pathway, whereas knockdown of NCAPD2 inhibited the Wnt/ß-catenin pathway. Moreover, NCAPD2 expression was significantly associated with immune cell infiltration, immune checkpoints, and drugs sensitivity. In conclusion, our study identified NCAPD2 as a novel oncogene in HCC and as a potential therapeutic target for HCC patients with DM.

Trends and drivers of anthropogenic NOx emissions in China since 2020.

Nitrogen oxides (NOx), significant contributors to air pollution and climate change, form aerosols and ozone in the atmosphere. Accurate, timely, and transparent information on NOx emissions is essential for decision-making to mitigate both haze and ozone pollution. However, a comprehensive understanding of the trends and drivers behind anthropogenic NOx emissions from China-the world's largest emitter-has been lacking since 2020 due to delays in emissions reporting. Here we show a consistent decline in China's NOx emissions from 2020 to 2022, despite increased fossil fuel consumption, utilizing satellite observations as constraints for NOx emission estimates through atmospheric inversion. This reduction is corroborated by data from two independent spaceborne instruments: the TROPOspheric Monitoring Instrument (TROPOMI) and the Ozone Monitoring Instrument (OMI). Notably, a reduction in transport emissions, largely due to the COVID-19 lockdowns, slightly decreased China's NOx emissions in 2020. In subsequent years, 2021 and 2022, reductions in NOx emissions were driven by the industry and transport sectors, influenced by stringent air pollution controls. The satellite-based inversion system developed in this study represents a significant advancement in the real-time monitoring of regional air pollution emissions from space.

Bioaccumulation, trophic transfer and risk assessment of polycyclic musk in marine food webs of the Bohai Sea.

Galaxolide (HHCB) and tonalide (AHTN) are dominant musks added to personal care products. However, the accumulate and trophic transfer of SMs through the marine food chain are unclear. In this study, organisms were collected from three bays in Bohai Sea to investigate the bioaccumulation, trophic transfer, and health risk of SMs. The HHCB and AHTN concentrations in the muscles range from 2.75 to 365.40 µg/g lw and 1.04-4.94 µg/g lw, respectively. The median HHCB concentrations in muscles were the highest in Bohai Bay, followed by Laizhou Bay and Liaodong Bay, consistent with the HHCB concentrations in sediments. The different fish tissues from Bohai Bay were analyzed, and the HHCB and AHTN concentrations followed the heart > liver > gill > muscles. The trophic magnification factors (TMF) were lower than 1 and the health risk assessment showed no adverse health effects. The results provide insights into the bioaccumulation and trophic transfer behavior of SMs in marine environments.

Natural Extracts for Antibacterial Applications.

Bacteria-induced epidemics and infectious diseases are seriously threatening the health of people around the world. In addition, antibiotic therapy has been inducing increasingly more serious bacterial resistance, which makes it urgent to develop new treatment strategies to combat bacteria, including multidrug-resistant bacteria. Natural extracts displaying antibacterial activity and good biocompatibility have attracted much attention due to greater concerns about the safety of synthetic chemicals and emerging drug resistance. These antibacterial components can be isolated and utilized as antimicrobials, as well as transformed, combined, or wrapped with other substances by using modern assistive technologies to fight bacteria synergistically. This review summarizes recent advances in natural extracts from three kinds of sources-plants, animals, and microorganisms-for antibacterial applications. This work discusses the corresponding antibacterial mechanisms and the future development of natural extracts in antibacterial fields.

Microwave-excited, antibacterial core-shell BaSO4/BaTi5O11@PPy heterostructures for rapid treatment of S. aureus-infected osteomyelitis.

Owing to its deep penetration capability, microwave (MW) therapy has emerged as a promising method to eradicate deep-seated acute bone infection diseases such as osteomyelitis. However, the MW thermal effect still needs to be enhanced to achieve rapid and efficient treatment of deep focal infected areas. In this work, the multi-interfacial core-shell structure barium sulfate/barium polytitanates@polypyrrole (BaSO4/BaTi5O11@PPy) was prepared, which exhibited enhanced MW thermal response via the well-designed multi-interfacial structure. To be specific, BaSO4/BaTi5O11@PPy achieved rapid temperature increases in a short period and efficient clearance of Staphylococcus aureus (S. aureus) infections under MW irradiation. After 15 min MW irradiation, the antibacterial efficacy of BaSO4/BaTi5O11@PPy can reach up to 99.61 ± 0.22%. Their desirable thermal production capabilities originated from enhanced dielectric loss including multiple interfacial polarization and conductivity loss. Additionally, in vitro analysis illuminated that the underlying antimicrobial mechanism was attributed to the noticeable MW thermal effect and changes in energy metabolic pathways on bacterial membrane instigated by BaSO4/BaTi5O11@PPy under MW irradiation. Considering remarkable antibacterial efficiency and acceptable biosafety, we envision that it has significant value in broadening the pool of desirable candidates to fight against S. aureus-infected osteomyelitis. STATEMENT OF SIGNIFICANCE: The treatment of deep bacterial infection remains challenging due to the ineffectiveness of antibiotic treatment and the susceptibility to bacterial resistance. Microwave (MW) thermal therapy (MTT) is a promising approach with remarkable penetration to centrally heat up the infected area. This study proposes to utilize the core-shell structure BaSO4/BaTi5O11@PPy as an MW absorber to achieve localized heating under MW radiation for MTT. In vitro experiments demonstrated that the disrupted bacterial membrane is primarily due to the localized high temperature and interrupted electron transfer chain. As a consequence, its antibacterial rate is as high as 99.61% under MW irradiation. It is shown that the BaSO4/BaTi5O11@PPy is a promising candidate for eliminating bacterial infection in deep-seated tissues.

Effect of HHCB and Cd on phytotoxicity, accumulation, subcellular distribution and stereoselectivity of chiral HHCB in soil-plant systems.

The toxicity of HHCB in the growth and development of plants is well known, but its uptake, subcellular distribution, and stereoselectivity, especially in a co-contamination environment, is not fully understood. Therefore, a pot experiment was performed to research the physiochemical response, and the fate of HHCB in pakchoi when the Cd co-existed in soil. The Chl contents were significantly lower, and the oxidative stress was aggravated under the co-exposure of HHCB and Cd. The accumulations of HHCB in roots were inhibited, and those in leaves were elevated. The transfer factors of HHCB in HHCB-Cd treatment increased. The subcellular distributions were analyzed in the cell walls, cell organelles, and cell soluble constituents of roots and leaves. In roots, the distribution proportion of HHCB followed cell organelle > cell wall > cell soluble constituent. In leaves, the distribution proportion of HHCB was different from that in roots. And the co-existing Cd made the distribution proportion of HHCB change. In the absence of Cd, the (4R,7S)-HHCB and (4R,7R)-HHCB were preferentially enriched in roots and leaves, and the stereoselectivity of chiral HHCB was more significant in roots than leaves. The co-existing Cd reduced the stereoselectivity of HHCB in plants. Our findings suggested that the fate of HHCB was affected by the co-existing Cd, so the risk of HHCB in the complicated environment should be paid more attention.

Clinical significance of anti-rheumatoid arthritis 33 antibody in patients with systemic lupus erythematosus.

Although anti-rheumatoid arthritis (RA) 33 antibodies have been reported to be present in various connective tissue diseases (CTDs), the clinical significance of anti-RA33 in CTDs is still obscure. This study was performed to explore the clinical significance of anti-RA33 in CTDs, especially systemic lupus erythematosus (SLE). A total of 565 patients with positive anti-nuclear antibodies who had been tested for anti-RA33 were included in this study and were further classified into RA33-positive and RA33-negative groups. The association between anti-RA33 and the clinical features of CTDs was examined. Receiver operating characteristic (ROC) analysis was performed to explore the diagnostic value of anti-RA33 in SLE and SLE-related organ involvement. The results showed that SLE was the most common disease in CTD patients positive for anti-RA33 (48.8%). Compared with the RA33-negative group, higher proportions of SLE-associated antibodies and SLE patients with a high disease activity as well as lower levels of serum complement components were observed in the RA33-positive group (all p < 0.05). Furthermore, CTD patients with positive anti-RA33 were more likely to suffer from mucocutaneous and hematological involvement as well as interstitial lung disease (all p < 0.05). ROC analysis revealed an area under the curve value of 0.634 (95% confidence interval: 0.587-0.681) for anti-RA33 in the diagnosis of SLE, with a specificity and sensitivity of 92.9% and 13.5%, respectively. Taken together, this study reveals a significant association between anti-RA33 and the clinical features of CTDs, especially SLE, indicating a potential clinical significance of anti-RA33 in the management of SLE.

Cobalt loaded electrospun poly(ε-caprolactone) grafts promote antibacterial activity and vascular regeneration in a diabetic rat model.

Diabetes has been associated with postoperative complications, such as increased risk of tissue infection and impaired tissue repair caused by destabilization of hypoxia-inducible factor-1α (HIF-1α). Consequently, it is imperative to fabricate anti-bacterial and pro-regenerative small-diameter vascular grafts for treating cardiovascular disease in diabetic patients. Herein, we developed electrospun cobalt ion (Co2+)-loaded poly (ε-caprolactone) (PCL) microfiber vascular grafts (PCL-Co grafts). The released Co2+ significantly increased the stabilization of HIF-1α in high-glucose (HG)-treated HUVECs (HG-HUVECs) and macrophages (HG-macrophages). This resulted in enhanced cell migration, nitric oxide production, and secretion of bioactive factors by HG-HUVECs, and polarization of HG-macrophages toward M2 phenotypes in vitro. The Co2+ also conferred anti-bacterial properties to the grafts, while not perturbing the inherent anti-bacterial activities of HG-macrophages. Following abdominal artery implantation into type 2 diabetes mellitus (T2DM) rats, PCL-Co grafts were evaluated for performance in infection (grafts pre-contaminated with Staphylococcus aureus) and prophylaxes models (grafts alone). PCL-Co grafts prevented the incidence of subsequent infection in prophylaxes model and effectively inhibited the bacterial growth in the infection model. PCL-Co grafts also significantly enhanced cellularization, vascularization, endothelialization, contractile SMC regeneration and macrophages polarization in both models. Collectively, PCL-Co grafts exhibited the potential to combat infection and improve tissue regeneration under diabetes conditions.

Current Progress in Natural Degradation and Enhanced Removal Techniques of Antibiotics in the Environment: A Review.

Antibiotics are used extensively throughout the world and their presence in the environment has caused serious pollution. This review summarizes natural methods and enhanced technologies that have been developed for antibiotic degradation. In the natural environment, antibiotics can be degraded by photolysis, hydrolysis, and biodegradation, but the rate and extent of degradation are limited. Recently, developed enhanced techniques utilize biological, chemical, or physicochemical principles for antibiotic removal. These techniques include traditional biological methods, adsorption methods, membrane treatment, advanced oxidation processes (AOPs), constructed wetlands (CWs), microalgae treatment, and microbial electrochemical systems (such as microbial fuel cells, MFCs). These techniques have both advantages and disadvantages and, to overcome disadvantages associated with individual techniques, hybrid techniques have been developed and have shown significant potential for antibiotic removal. Hybrids include combinations of the electrochemical method with AOPs, CWs with MFCs, microalgal treatment with activated sludge, and AOPs with MFCs. Considering the complexity of antibiotic pollution and the characteristics of currently used removal technologies, it is apparent that hybrid methods are better choices for dealing with antibiotic contaminants.

Effects of polyester microfibers (PMFs) and cadmium on lettuce (Lactuca sativa) and the rhizospheric microbial communities: A study involving physio-biochemical properties and metabolomic profiles.

Microfibers (MFs) and cadmium (Cd) are widely distributed in soil ecosystems, posing a potential threat to soil biota. To explore potential risks of single MFs and in combination with Cd (co-PMFs/Cd) to soil environment, we systematically investigated the effects of PMFs and co-PMFs/Cd treatments on physio-biochemical performance and metabolomic profile of lettuce (Lactuca sativa), as well as the rhizospheric bacterial communities. Our results showed that both PMFs and co-PMFs/Cd treatments adversely disturbed the plant shoot length, photosynthetic, and chlorophyll content. Co-PMFs/Cd specifically increased the activities of antioxidant enzymes. The metabolites in lettuce leaf were significantly altered by PMFs and co-PMFs/Cd treatments. A significant reduction in the relative abundance of amino acids sugar and sugar alcohols indicated the altered nitrogen and carbohydrates related metabolic pathways. Additionally, PMFs and co-PMFs/Cd treatments altered the structure of rhizospheric bacterial communities and caused significant changes in some key beneficial/functional bacteria involved in the C, and N cycles. The present study provides a novel insight into the potential effects of PMFs on plant and rhizosphere bacterial communities and highlights that PMFs can threaten the terrestrial ecosystem and should be further explored in future research.

Epidemiological survey of the status of iodine nutrition and thyroid diseases in Guangxi, China.

OBJECTIVE: To survey the status of iodine nutrition and the prevalence of thyroid diseases in Guangxi, China, and to explore the risk factors for positive thyroid antibody. METHODS: We used the multistage stratified cluster random sampling method to select a total of 2488 subjects from an urban and a rural location. All the subjects completed a questionnaire survey, blood and urine samples were also collected, and B-mode thyroid ultrasound was used to determine thyroid function and detect thyroid antibodies. RESULTS: 1) The median level of urinary iodine was 148.53 µg/L in school-age children in Guangxi, China. 2) The prevalence rates for thyroid diseases were as follows: hyperthyroidism, 0.89 %; subclinical hyperthyroidism, 1.05 %; hypothyroidism, 0.69 %; and subclinical hypothyroidism, 8.87 %. The rates of thyroid antibody positivity were as follows: thyroid peroxidase antibody (TPOAb), 13.60 %; thyroglobulin antibody (TGAb), 13.60 %; thyroid antibodies, 18.2 %; and thyroid nodules, 16.94 %. 3) The rate of TPOAb positivity was significantly higher in women aged 18-29, 30-39, 40-49, or 60-69 years than in men in the same age groups (P < 0.05), and the TGAb positivity rate was significantly higher in women than in men of the same age group (P < 0.05). 4) The rate of thyroid antibody positivity was significantly higher in individuals with iodine deficiency than in individuals with adequate iodine (21.6 % vs 18.4 %) or excess iodine (21.6 % vs 15.5 %) (both P < 0.05). 5) The female sex and a family history of thyroid diseases were the major risk factors for thyroid antibody positivity (odds ratio [OR] 3.010, P <0.05; OR 2.486, P <0.05). CONCLUSION: The overall level of iodine is adequate in Guangxi, China; this level should be maintained to prevent the thyroid diseases related with iodine deficiency or excess of iodine. Female sex and a family history of thyroid diseases are independent risk factors for thyroid antibody positivity.

Case Report: Rapidly Progressive Interstitial Lung Disease in A Pregnant Patient With Anti-Melanoma Differentiation-Associated Gene 5 Antibody-Positive Dermatomyositis.

Dermatomyositis occurs extremely rarely during pregnancy. A number of studies in the published literature have documented how the outcome of pregnancy is poor for both mother and fetus. The present case study reports on a patient who was diagnosed with clinically amyopathic dermatomyositis complicated by interstitial lung disease during pregnancy, and was successfully treated with a combined immunosuppressant regimen. To the best of the authors' knowledge, this is the first case study detailing how a pregnant woman with clinically amyopathic dermatomyositis with positive anti-melanoma differentiation-associated gene 5 antibody achieved complete remission after early intervention of combined immunosuppressive therapy without residual pulmonary interstitial changes.

Dorsolateral medullary infarction during skin infection by Stenotrophomonas maltophilia in a patient with triple antiphospholipid antibody positivity: a case-based review.

Thrombotic events are the most frequent causes of death in patients with antiphospholipid syndrome (APS). Previous studies have reported infection to be the most important trigger of thrombosis in APS, with molecular mimicry considered to be a major mechanism. Although timely management of infections has been recommended in patients with high suspicion of infection, anti-infective therapy would not take effect in a short time due to the dilemma in determining the origins of infection, especially in patients undergoing immunosuppressive therapy. Here, we describe a 26-year-old patient with systemic lupus erythematosus with triple antiphospholipid antibody positivity who had a stroke involving her dorsolateral medulla, despite timely anti-infective treatment within the context of skin infection caused by Stenotrophomonas maltophilia. To the best of our knowledge, it is the first report about the association between Stenotrophomonas maltophilia infection and thrombotic complications in APS. Thus, solely focusing on anti-infective therapy by the current recommendation for the management of APS may be insufficient within the context of infection; early initiation of effective anticoagulation should also be suggested until the anti-infective therapy becomes effective, especially in patients with high-risk antiphospholipid antibody profiles, in whom the potential benefit would outweigh the risk of bleeding.

Switchable Synthesis of Arylalkynes and Phthalides via Controllable Palladium-Catalyzed Alkynylation and Alkynylation-Annulation of Benzoic Acids with Bromoalkynes.

A ligand-promoted palladium(II)-catalyzed synthesis of arylalkynes and phthalides from benzoic acids and bromoalkynes via carboxylate-assisted ortho-C-H activation is reported. A series of phthalides with various functional groups are prepared via ortho-alkynylation and alkynylation-annulation. Moreover, the key ortho-alkynylated products are also obtained by controlling the reaction conditions. In addition, heteroaryl acids could react smoothly to form the corresponding alkynylation and cyclization products.

Role of extracellular polymeric substances on the behavior and toxicity of silver nanoparticles and ions to green algae Chlorella vulgaris.

The effect of extracellular polymeric substances (EPS), vital organic matters and nutrient elements in the natural environment, on the behavior and toxicology of silver nanoparticles (AgNPs) and ions remains ambiguous. In this study, the role of EPS on the toxicity of AgNPs and dissolved silver ions (from AgNO3) to a green algae Chlorella vulgaris was investigated. After the removal of EPS, algae accumulated more silver, about 7.41- and 1.25-fold of those in the algae with EPS for AgNPs and AgNO3 treatments, respectively. The large amount of accumulated silver was bound to the algal cell surface for AgNPs treatment and was internalized in the algae for AgNO3 treatment, irrespective of the presence of EPS in algae. After exposure to AgNPs, the ruffles in the surfaces of algal cells were filled by AgNPs, and almost invisible. FTIR showed that for both AgNPs and AgNO3, the aldehyde groups on the cell surface were oxidized to carboxyl groups by silver ions, irrespective of the presence of EPS in algal cells, indicating that silver ions were released from the oxidization of AgNPs and reacted with algal cells. The content of chlorophyll showed that AgNPs depressed algal growth more remarkably than did AgNO3, independent of the presence of EPS in algae, suggesting that AgNPs had greater toxic effects on algae than did silver ions. The findings suggest that the barrier effect of EPS gave nanoparticles an extraordinary edge over ions, but EPS had no discerning effect on the interaction of algal cells with the silver ions released from AgNPs and AgNO3, and also on the effect of AgNPs and AgNO3 on algal growth.

Influence of acylglycerol emulsifier structure and composition on the function of shortening in layer cake.

The effect of the structure and composition of acylglycerol emulsifiers on the functionality of a palm-based shortening and quality of layer cake was investigated. The emulsifiers evaluated were distilled monoacylglycerol (DMG) and four acylglycerols (40% monoacylglycerol content) of octanoic acid (8:0), palmitic acid (16:0), stearic acid (18:0), and linoleic acid (18:2), designated as GMOct40, GMP40, GMS40, and GML40, respectively. The addition of GMP40 and GMS40 led to shortening with a higher solid fat content, finer crystals, and higher proportion of ß' form. These changes enhanced shortening's function in aiding air incorporation and retention in cake batter, which improved the cake's volume and crumb structure. However, the high monoacylglycerol content in DMG did not improve the properties of shortening and cake as compared to GMP40. In contrast, GML40 and GMOct40 had adverse effects on the functionality of shortening, which generated cakes with inferior crumb structure.

Effects of Irbesartan Pretreatment on Pancreatic ß-Cell Apoptosis in STZ-Induced Acute Prediabetic Mice.

The current study was performed to investigate the effects and potential effects of irbesartan pretreatment on pancreatic ß-cell apoptosis in a streptozotocin- (STZ-) induced acute mouse model of prediabetes. Twenty-four male BALB/C mice (18-22 g) were randomly divided into three groups: normal control group (NC, n = 6), STZ group (STZ, n = 8), and irbesartan + STZ group (IRB + STZ, n = 10). In the IRB + STZ group, mice were administered irbesartan (300 mg/kg per day) by gavage for one week. The STZ group and IRB + STZ group received STZ (80 mg/kg by intraperitoneal (IP) injection once). The NC group received normal saline (80 mg/kg by IP injection once). Fasting blood glucose prior to STZ injection and presacrifice was analysed using samples withdrawn from the caudal vein to confirm the induction of prediabetes. Haematoxylin and eosin staining, immunohistochemical detection of insulin, and apoptosis analysis were performed. Reverse transcription-quantitative polymerase chain reaction was used to detect angiotensin II type 1 receptor (AT1R), caspase-3, and p38 mitogen-activated protein kinase (MAPK) mRNA expression. Blood glucose was significantly higher in the STZ group (9.01 ± 1.1089 vs 4.78 ± 0.7026) and IRB + STZ group (7.86 ± 1.1811 vs 4.78 ± 0.7026) compared with the NC group (P < 0.05). In comparison to the STZ group, the islet cell damage was marginally improved in the IRB + STZ group, and the IRB + STZ group had a significantly lower apoptotic rate than the STZ group (22.42 ± 8.3675 vs 50.86 ± 5.3395, P < 0.001). AT1R expression in the IRB + STZ group was lower than that in the STZ group (1.56 ± 1.2207 vs 3.92 ± 2.4392, P < 0.05). The mRNA expression of caspase-3 in pancreatic tissue was significantly lower in the IRB + STZ group than in the STZ group (0.90 ± 0.7272 vs 1.88 ± 1.0572, P < 0.05). Similarly, the IRB + STZ group also had lower p38MAPK levels than the STZ group (1.16 ± 1.0642 vs 2.55 ± 1.7925, P > 0.05). In conclusion, irbesartan pretreatment improved glucose levels and insulin secretion and decreased islet ß-cell apoptosis to protect islet ß cells in an STZ-induced acute prediabetic mouse model.

Physiological and Antioxidant Responses in Wheat (Triticum aestivum) to HHCB in Soil.

Seedlings of wheat (Triticum aestivum) were exposed in soil to the polycyclic musk chemical, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran (HHCB) for 21 days, to evaluate its effect upon chlorophyll (CHL), lipid peroxidation and the antioxidant system. The content of CHL in leaves was inhibited significantly after 14- and 21-days exposures, whereas it was significantly induced by a low level of HHCB after a 7-days exposure. The content of malondialdehyde (MDA) in wheat leaves increased with an increase in the concentration of HHCB in soil, indicating that oxidative stress could be induced by HHCB. Moreover, HHCB exposure induced significant antioxidant responses in wheat. The activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in wheat leaves were induced by HHCB after 14 and 21 days of exposure. However, the changing trend of the antioxidant enzymes in wheat roots was different from that in leaves. The results suggested that the assayed parameters of T. aestivum could be used as responsive biomarkers for oxidative stress in the soil environment.

Effect of soil HHCB on cadmium accumulation and phytotoxicity in wheat seedlings.

The accumulation of cadmium (Cd) in wheat seedlings under single and joint stress of galaxolide (HHCB) and Cd was investigated, and their phytotoxicity and oxidation stress including chlorophyll (CHL), malondialdehyde (MDA), superoxide dismutase, and perosidase were assessed. The results showed that the accumulation of Cd in wheat seedlings increased with an increase in the concentration of Cd in soil. The low concentration of HHCB inhibited the accumulation of Cd, while the high concentration of HHCB induced the accumulation of Cd. The content of CHL increased significantly in treatments with 1-50 mg kg(-1) Cd. However, the content of CHL under joint stress of Cd and HHCB was significantly lower than that in the control. Besides, the content of MDA in wheat leaves and roots was also significantly affected by HHCB and Cd, particularly by their joint stress. Co-contamination of HHCB significantly affected the activity of antioxidant enzymes in wheat seedlings stressed by Cd. In a word, HHCB could aggravate the phytotoxicity of Cd to wheat seedlings.

Responses of oxidative stress biomarkers and DNA damage on a freshwater snail (Bellamya aeruginosa) stressed by ethylbenzene.

Ethylbenzene is classified as a priority pollutant; however, toxicity data, especially those regarding sublethal toxicity, are rarely reported on gastropods. The present work was performed to elucidate the sublethal effects of ethylbenzene using a freshwater snail, Bellamya aeruginosa (Reeve), exposed to ethylbenzene for 21 days followed by a 17-day recovery period. Superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), reduced glutathione (GSH), and malonyldialdehyde (MDA) were used as biomarkers to evaluate oxidative stress in hepatopancreas of snails. In addition, alkaline comet assay was applied to determine the genotoxicity of ethylbenzene in hepatopancreas of snails. These biomarkers and DNA damage exhibited various responses to ethylbenzene in the tested snails. SOD and CAT activities were almost significantly stimulated during the exposure period. As exposure time was prolonged beyond 7 days, CAT activity gradually became significantly increased at higher doses of ethylbenzene. GSH concentration was positively and linearly related with exposure dose. MDA concentration was significantly greater than that in the control only under the lowest treatment after a 7-day exposure. Alkaline comet assay showed that ethylbenzene could significantly induce DNA damage in hepatopancreas of snails, and there was a good dose- and time-response in DNA damage, indicating potential genotoxicity of ethylbenzene on snails. At the end of the recovery period, the repair of DNA damage was not yet completed, showing that DNA repair requires more time. The findings from this study could indicate that SOD, GST, and GSH seem to be effective oxidative biomarkers for snails exposed to ethylbenzene in the short term. CAT proved to be a valuable discriminating biomarker in subchronic exposure to ethylbenzene, but MDA was not a suitable oxidative biomarker for exposure to ethylbenzene in either the short or long term. Alkaline comet assay was efficient tool with which to evaluate the potential genotoxicity of ethylbenzene.