[Antagonistic Effect and Mechanism of Nano Titanium Dioxide and Cadmium on the Growth of Scenedesmus obliquus].

The release of manufactured nanomaterials (MNMs) into the environment has raised concerns about combined toxicological risks, as MNMs could significantly alter the environmental behavior and fate of co-existing contaminants. Numerous studies have been published on the combined toxicity of MNMs and co-existing contaminants, but the potential mechanisms controlling the combined toxicity, especially the biological response mechanism, remain unclear. This study investigated the combined toxicity of nano-titanium dioxide (nTiO2), a typical MNM, and the heavy metal cadmium (Cd2+), using Scenedesmus obliquus as the test organism. The molecular mechanism was examined under different concentrations, using an equivalent dose (toxic ratio 1 ∶1) on S. obliquus. The results showed that the 72h-EC50 of nTiO2 and Cd2+ at the equivalent dose was significantly higher than that of single exposure, indicating an antagonistic effect. Further transcriptomics analysis revealed that the photosynthesis, chlorophyll metabolism, and starch and sucrose metabolism pathways involved in the energy metabolism of S. obliquus were significantly up-regulated in the presence of nTiO2. The arginine and proline metabolic pathways related to the anti-stress effect of algae cells also showed positive stimulation. The results of this study provide an important reference and a research basis for in-depth understanding of the environmental effects of MNMs and co-existing contaminants.

miR-381-3p inhibits high glucose-induced vascular smooth muscle cell proliferation and migration by targeting HMGB1.

BACKGROUND: Hyperglycemia increases the risk of many cardiovascular diseases (CVD), and the dysregulation of proliferation and migration in vascular smooth muscle cells (VSMCs) also participates in the pathogenesis of CVD. miR-381-3p is known to suppress the proliferation and migration of multiple human cell types. Nevertheless, the function of miR-381-3p in VSMCs remains largely indistinct. METHODS: A quantitative real-time polymerase chain reaction (qRT-PCR) was employed to investigate miR-381-3p expression in high-glucose-induced VSMCs. Inflammatory cytokines tumor necrosis factor-α, interleukin-1ß and interleukin-6, as well as oxidative stress markers SOD and MDA, were determined by an enzyme-linked immunosorbent assay. Reactive oxygen species generation was examined using a 2,7'-dichlorofluorescein kit. The proliferation, migration and apoptosis of VSMCs were monitored by 3-(4,5-dimethylthiazl2-yl)-2,5-diphenyltetazolium bromide (MTT), transwell and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assays. The TargetScan database (http://www.targetscan.org) was employed to seek the potential target gene of miR-381-3p. Interaction between miR-381-3p and HMGB1 was determined by a qRT-PCR, western blotting and a luciferase reporter assay. RESULTS: miR-381-3p expression was significantly reduced in a VSMCs dysfunction model induced by high-glucose in a dose- and time-dependent manner. Transfection of miR-381-3p mimics suppressed the inflammation, oxidative stress, proliferation and migration of VSMCs, whereas apoptosis of VSMCs was promoted, and the transfection of miR-381-3p inhibitors had the opposite effect. Mechanistically, HMGB1, an important factor in inflammation response, was confirmed as a target gene of miR-381-3p. CONCLUSIONS: miR-381-3p targets HMGB1 to suppress the inflammation, oxidative stress, proliferation and migration of high-glucose-induced VSMCs by targeting HMGB1.

A Novel Hydrolytic Activity of Tri-Functional Geranylgeranyl Pyrophosphate Synthase in Haematococcus pluvialis.

Under environmental stresses, Haematococcus pluvialis accumulates large amounts of carotenoids. Scale of carotenoid biosynthesis depends on availability of geranylgeranyl pyrophosphate (GGPP) precursor, which is supplied by GGPP synthase (GGPPS) through sequential 1'-4 condensation of three isopentenyl pyrophosphates (IPPs) into dimethylallyl pyrophosphate (DMAPP). Using IPP and DMAPP as substrates, a tri-functional HpGGPPS was identified in this study to promiscuously synthesize allylic prenyl pyrophosphates (PPPs), e.g. C10 geranyl pyrophosphate (GPP), C15 farnesyl pyrophosphate (FPP), and C20 GGPP. Intriguingly, HpGGPPS can utilize GPP or FPP as a single substrate to synthesize GGPP by hydrolyzing the allylic PPP substrate into C5 IPP. Transcription of HpGGPPS and key carotenogenesis genes, morphological transformation, and carotenoid biosynthesis were differentially induced by environmental stresses, while HpGGPPS's products were low in vivo, implying that most of PPP flux had been shunted into carotenoid biosynthesis. Hydrolyzing allylic PPP intermediates into C5 building blocks by promiscuous HpGGPPS may be a fail safe for carotenoid accumulation against environmental stress.

Retraction Note: Nuclear factor of activated T cells 5 maintained by Hotair suppression of miR-568 upregulates S100 calcium binding protein A4 to promote breast cancer metastasis.

The authors are retracting this article [1] after an investigation by the Ethics Committee of the Fourth Military Medical University (Xi'an, Shaanxi, China) of the following concerns that had been raised with respect to two of the figures.

[Fate and Toxicity of UV Filters in Marine Environments].

UV filters have been widely used in sunscreen products, and they have partially ended up in the marine environment via human recreational activities and sewage treatment plant drainage, becoming one of the emerging marine pollutants. As UV filters have many characteristics, such as extensive use, continuous emissions, and stability, their potential risks to the environment and ecology have become a hot topic in the field of environmental research all over the world. This study analyzed the environmental behavior of UV filters in the ocean, such as migration, transformation, and volatilization. The toxic effects (i. e., growth inhibition, reproductive inhibition, death, and malformation) of the inorganic (mainly nano-TiO2 and nano-ZnO) and organic UV filters (mainly benzophenones, camphor derivatives, and cinnamic acids) on marine organisms (i. e., algae, seashell, fish, coral, and sea urchin) were summarized. The research also analyzed the inherent toxicity mechanisms from the perspective of oxidative damage, neurotoxicity, and endocrine disability. The prospect and future directions in this field were also discussed. This review provides a reference for scientific research and pollution control related to UV filters.

Epithelial HO-1/STAT3 affords the protection of subanesthetic isoflurane against zymosan-induced lung injury in mice.

Epithelial dysfunction is a key characteristic of acute lung injury (ALI). Isoflurane (ISO) confers lung protection via anti-inflammatory and anti-apoptotic properties. However, the specific role and potential mechanisms of subanesthetic ISO in lung epithelium protection during zymosan-induced ALI remain unclear. In this study, zymosan increased the expression and activity of beneficial heme oxygenase-1 (HO-1) and signal transducers and activators of transcription 3 (STAT3) in the lung and isolated type II alveolar epithelial cells (AECs-II) from wild-type (WT) mice, which was further enhanced by ISO treatment. ISO reduced the mortality, lung edema, histological changes and pulmonary cell apoptosis, and simultaneously decreased total cells, tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) levels in bronchoalveolar lavage fluid in the zymosan-stimulated WT mice but not in HO-1-deficient mice. Moreover, ISO abated zymosan-augmented lactate dehydrogenase activity, TNF-α and IL-1ß production, and apoptosis in WT AECs-II but not in HO-1- or STAT3-silenced cells. Mechanisticly, the epithelial protective effects of ISO on zymosan insult in vivo and in vitro were mediated by a positive feedback loop comprising STAT3 and HO-1. Pro-survival and anti-apoptosis by ISO was highly reliant on activated STAT3, involving in downstream Akt activation and reduced ratio of pro-apoptotic/anti-apoptotic molecules. Overall, HO-1/STAT3 signaling is in favor of lung epithelial protection of ISO in zymosan-challenged mice, suggesting ISO as a valuable therapeutic agent for ALI.

Swimming attenuates inflammation, oxidative stress, and apoptosis in a rat model of dextran sulfate sodium-induced chronic colitis.

Increasing evidence suggests that regular physical exercise suppresses chronic inflammation. However, the potential inhibitory effects of swimming on dextran sulfate sodium (DSS)-induced chronic colitis, and its underlying mechanisms, remain unclear. In this study, rats were orally administered DSS to induce chronic colitis, and subsequently treated with or without swimming exercise. A 7-week swimming program (1 or 1.5 hours per day, 5 days per week) ameliorated DSS-caused colon shortening, colon barrier disruption, spleen enlargement, serum LDH release, and reduction of body weight gain. Swimming for 1.5 hours per day afforded greater protection than 1 hour per day. Swimming ameliorated DSS-induced decrease in crypt depth, and increases in myeloperoxidase activity, infiltration of Ly6G+ neutrophils and TNF-α- and IFN-γ-expressing CD3+ T cells, as well as fecal calprotectin and lactoferrin. Swimming inhibited pro-inflammatory cytokine and chemokine production and decreased the protein expression of phosphorylated nuclear factor-κB p65 and cyclooxygenase 2, whereas it elevated interleukin-10 levels. Swimming impeded the generation of reactive oxygen species, malondialdehyde, and nitric oxide; however, it boosted glutathione levels, total antioxidant capacity, and superoxide dismutase and glutathione peroxidase activities. Additionally, swimming decreased caspase-3 activity and expression of apoptosis-inducing factor, cytochrome c, Bax, and cleaved-caspase-3, but increased Bcl-2 levels. Overall, these results suggest that swimming exerts beneficial effects on DSS-induced chronic colitis by modulating inflammation, oxidative stress, and apoptosis.

Subanesthetic isoflurane relieves zymosan-induced neutrophil inflammatory response by targeting NMDA glutamate receptor and Toll-like receptor 2 signaling.

Neutrophil release of NO/ONOO- induces endothelial cell barrier dysfunction in inflammatory acute lung injury (ALI). Previous studies using zymosan-triggered inflammation and ALI model revealed that zymosan promotes inducible NO synthase (iNOS) expression in neutrophils, and that isoflurane inhibits zymosan-induced oxidative stress and iNOS biosynthesis. However, the underlying mechanisms remain largely unknown. We found here that in zymosan-primed neutrophils, iNOS is transcriptionally activated by NF-κB, whose nuclear translocation is triggered by excessive reactive oxygen species (ROS) and consequently activated p38 MAPK. ROS production is attributed to zymosan-initiated Toll-like receptor 2 (TLR2) signaling, in which the adaptor MyD88 recruits and activates c-Src, and c-Src activates NADPH oxidase to generate ROS. Subanesthetic isoflurane counteracts the aforementioned zymosan-induced signaling by targeting N-methyl-D-aspartic acid (NMDA) glutamate receptor and thereby suppressing calcium influx and c-Src activation. Whereas iNOS accelerates NO/ONOO- production in neutrophils which eventually promote protein leak from pulmonary microvascular endothelial cells (PMVEC), isoflurane reduced NO/ONOO- release from zymosan-treated neutrophils, and thus relieves trans-PMVEC protein leak. This study provides novel insights into the roles of neutrophils and the underlying mechanisms in zymosan-induced ALI, and has implications for the therapeutic potential of subanesthetic isoflurane in attenuating inflammatory responses causing lung endothelial cell damage.

Targeting ubiquitin-specific protease 22 suppresses growth and metastasis of anaplastic thyroid carcinoma.

Ubiquitin-specific protease 22 (USP22) aberrance has been implicated in several malignancies; however, whether USP22 plays a role in anaplastic thyroid carcinoma (ATC) remains unclear. Here, we report that USP22 expression is highly elevated in ATC tissues, which positively correlated with tumor size, extracapsular invasion, clinical stages, and poor prognosis of ATC patients. In vitro assays showed that USP22 depletion suppressed ATC cell survival and proliferation by decreasing Rb phosphorylation and cyclin D2, inactivating Akt, and simultaneously upregulating Rb; USP22 silencing restrained cell migration and invasion by inhibiting epithelial-mesenchymal transition; USP22 knockdown promoted mitochondrion- mediated and caspase-dependent apoptosis by upregulating Bax and Bid and promoting caspase-3 activation. Consistent with in vitro findings, downregulation of USP22 in ATC cells impeded tumor growth and lung metastasis in vivo. These results raise the applicability for USP22 as a useful predictor of ATC prognosis and a potential therapeutic target for ATC.

MiRNA-101 inhibits breast cancer growth and metastasis by targeting CX chemokine receptor 7.

Whereas miR-101 is involved in the development and progression of breast cancer, the underlying molecular mechanisms remain to be elucidated. Here, we report that miR-101 expression is inversely correlated with the clinical stage, lymph node metastasis and prognosis in breast cancers. Introduction of miR-101 inhibited breast cancer cell proliferation and invasion in vitro and suppressed tumor growth and lung metastasis of in vivo. CX chemokine receptor 7 (CXCR7) is a direct target of miR-101, positively correlating with the histological grade and the incidence of lymph node metastasis in breast cancer patients. The effects of miR-101 were mimicked and counteracted by CXCR7 depletion and overexpression, respectively. STAT3 signaling downstream of CXCR7 is involved in miR-101 regulation of breast cancer cell behaviors. These findings have implications for the potential application of miR-101 in breast cancer treatment.

Nuclear factor of activated T cells 5 maintained by Hotair suppression of miR-568 upregulates S100 calcium binding protein A4 to promote breast cancer metastasis.

INTRODUCTION: The onset of distal metastasis, which underlies the high mortality of breast cancers, warrants substantial studies to depict its molecular basis. Nuclear factor of activated T cells 5 (NFAT5) is upregulated in various malignancies and is critically involved in migration and invasion of neoplastic cells. Nevertheless, the metastasis-related events potentiated by this transcriptional factor and the mechanism responsible for NFAT5 elevation in carcinoma cells remain to be fully elucidated. METHODS: The correlation of NFAT5 with breast cancer invasiveness was investigated in vitro and clinically. The genes transcriptionally activated by NFAT5 were probed and their roles in breast cancer progression were dissected. The upstream regulators of NFAT5 were studied with particular attempt to explore the involvement of non-coding RNAs, and the mechanism underlying the maintenance of NFAT5 expression was deciphered. RESULTS: In metastatic breast cancers, NFAT5 promotes epithelial-mesenchymal transition (EMT) and invasion of cells by switching on the expression of the calcium binding protein S100A4, and facilitates the angiogenesis of breast epithelial cells and thus the development of metastases by transcriptionally activating vascular endothelial growth factor C (VEGF-C). NFAT5 is directly targeted by miR-568, which is in turn suppressed by the long non-coding RNA, Hotair, via a documented in trans gene silencing pattern, that is recruitment of the polycomb complex (Polycomb Repressive Complex 2; PRC2) and LSD1, and consequently methylation of histone H3K27 and demethylation of H3K4 on the miR-568 loci. CONCLUSION: This study unravels a detailed role of NFAT5 in mediating metastatic signaling, and provides broad insights into the involvement of Hotair, in particular, by transcriptionally regulating the expression of microRNA(s), in the metastasis of breast cancers.

Subanesthetic isoflurane reduces zymosan-induced inflammation in murine Kupffer cells by inhibiting ROS-activated p38 MAPK/NF-κB signaling.

Volatile anesthetic isoflurane (ISO) has immunomodulatory effects. The fungal component zymosan (ZY) induces inflammation through toll-like receptor 2 or dectin-1 signaling. We investigated the molecular actions of subanesthetic (0.7%) ISO against ZY-induced inflammatory activation in murine Kupffer cells (KCs), which are known as the resident macrophages within the liver. We observed that ISO reduced ZY-induced cyclooxygenase 2 upregulation and prostaglandin E2 release, as determined by western blot and radioimmunoassay, respectively. ISO also reduced the production of tumor necrosis factor-α, interleukin-1ß, IL-6, high-mobility group box-1, macrophage inflammatory protein-1α, macrophage inflammatory protein-2, and monocyte chemoattractant protein-1 as assessed by enzyme-linked immunosorbent assays. ISO blocked the ZY-induced nuclear translocation and DNA-binding activity of nuclear factor- (NF)-κB p65. Moreover, ISO attenuated ZY-induced p38 mitogen-activated protein kinase (MAPK) activation partly by scavenging reactive oxygen species (ROS); the interregulation that ROS activated p38 MAPK followed by NF-κB activation was crucial for the ZY-induced inflammatory responses in KCs. An in vivo study by peritoneal injection of ZY into BALB/C mice confirmed the anti-inflammatory properties of 0.7% ISO against ZY in KCs. These results suggest that ISO ameliorates ZY-induced inflammatory responses in murine KCs by inhibiting the interconnected ROS/p38 MAPK/NF-κB signaling pathways.

[Comparative study on effects between electroacupuncture and acupuncture for spastic paralysis after stroke].

OBJECTIVE: To observe the differences of therapeutic effect of spastic paralysis after stroke between electroacupuncture and acupuncture and explore the mechanism. METHODS: Sixty-four cases were randomly divided into an electroacupuncture group (n = 33) and an acupuncture group (n = 31). Both groups were treated with Bobath facilitation techniques and medicine treatments. Quchi (LI 11), Hegu (LI 4), Yanglingquan (GB 34), Sanyinjiao (SP 6), et al. on the affected side were selected in each group. The needle was retained for 30 min, and the manipulation was applied for 1 min in the acupuncture group, and electroacupuncture was added in the electroacupuncture group. Stroke Impairment Assessment Set (SIAS) was adopted to assess the whole function status after sroke, and the contents of glutamate (Glu) and gamma-aminobutyric acid (GABA) in serum and clinical efficacy were observed in the two groups. RESULTS: The SIAS score increased after treatment as compared with that before treatment in either group (both P < 0.01), and the electroacupuncture group was superior to the acupuncture group (P < 0.01); the content of Glu in blood serum and ratio of Glu/GABA reduced, while the content of GABA in serum increased after treatment as compared with those before treatment in either group (all P < 0.01), but the improvement of above indices were much more apparently in the electroacupuncture group as compared with those in the acupuncture group (P < 0.01, P < 0.05); the total effective rate of 90.9% (30/33) in the electroacupuncture group was superior to that of 83.9% (26/31) in the acupuncture group (P < 0.05). CONCLUSION: Electroacupuncture can improve therapeutic effect of spastic paralysis after stroke, it's mechanism may be ralated to ajusting the contents of Glu and GABA in serum.

Influences of DMP on the fertilization process and subsequent embryogenesis of abalone (Haliotis diversicolor supertexta) by gametes exposure.

Di-methyl phthalate (DMP), a typical endocrine disrupting chemical (EDC), is ubiquitously distributed in aquatic environments; yet studies regarding its impact on gametes and the resulting effects on embryogenesis in marine gastropods are relatively scarce. In this study, the influences of DMP on the gametes and subsequent developmental process of abalone (Haliotis diversicolor supertexta, a representative marine benthic gastropod) were assessed. Newborn abalone eggs and sperm were exposed separately to different DMP concentrations (1, 10 or 100 ppb) for 60 min. At the end-point of exposure, the DMP-treated eggs and sperm were collected for analysis of their ultra-structures, ATPase activities and total lipid levels, and the fertilized gametes (embryos) were collected to monitor related reproductive parameters (fertilization rate, abnormal development rate and hatching success rate). Treatment with DMP did not significantly alter the structure or total lipid content of eggs at any of the doses tested. Hatching failures and morphological abnormalities were only observed with the highest dose of DMP (100 ppb). However, DMP exposure did suppress sperm ATPase activities and affect the morphological character of their mitochondria. DMP-treated sperm exhibited dose-dependent decreases in fertilization efficiency, morphogenesis and hatchability. Relatively obvious toxicological effects were observed when both sperm and eggs were exposed to DMP. Furthermore, RT-PCR results indicate that treatment of gametes with DMP changed the expression patterns of physiologically-regulated genes (cyp3a, 17ß-HSD-11 and 17ß-HSD-12) in subsequent embryogenesis. Taken together, this study proofed that pre-fertilization exposure of abalone eggs, sperm or both to DMP adversely affects the fertilization process and subsequent embryogenesis.

The impacts of bisphenol A (BPA) on abalone (Haliotis diversicolor supertexta) embryonic development.

The effects of bisphenol A (BPA) on abalone (Haliotis diversicolor supertexta) embryonic development were investigated by exposing the fertilized eggs to four different concentrations of BPA (0.05, 0.2, 2 and 10 µg mL(-1)). Toxicity endpoints including the embryo development parameters, the physiological features and the expression profile of several reference genes (prohormone convertase 1, PC1; cyclin B, CB; and cyclin-dependent kinase 1, CDK1) were assessed. The results showed that BPA could markedly reduce embryo hatchability, increase developmental malformation, and suppress the metamorphosis behavior of larvae. The possible toxicological mechanisms hidden behind of these effects (i.e. disturbing the embryogenesis) might result from three aspects: (1) BPA disturbance the cellular ionic homeostasis and osmoregulation of abalone embryos by changing the Na+-K+-ATPase and Ca2+-Mg2+-ATPase levels; (2) BPA induced oxidative damage of embryos by significantly altering the peroxidase (POD) activities and the malondialdehyde (MDA) production; and (3) the RT-PCR analysis further demonstrated that BPA perturbed the cellular endocrine regulation and cell cycle progression by down-regulating the PC1 gene, as well as over-expressing the CB and CDK1 genes. This is the first comprehensive study on the developmental toxicity of BPA to the marine abalone at morphological, physiological and molecular levels. The results in this study also indicated that the embryo tests can contribute to the ecological risk assessment of the endocrine disruptors in marine environment.

Are endocrine disruptors among the causes of the deterioration of aquatic biodiversity?

Exposure to environmental pollutants such as endocrine-disrupting compounds (EDCs) is now taken into account to explain partially the biodiversity decline of aquatic ecosystems. Much research has demonstrated that EDCs can adversely affect the endocrine system, reproductive health, and immune function in aquatic species. These toxicological effects include 1) interference with normal hormonal synthesis, release, and transport, 2) impairment of growth, development, and gonadal maturation, and 3) increased sensitivity to environmental stressors. Recent studies also have confirmed that EDCs have carcinogenic and mutagenic potential. In essence, these changes in physiological and biochemical parameters reflect, to some extent, some phenotypic characteristics of the deterioration of aquatic biodiversity. At present, evidence at the molecular level shows that exposure to EDCs can trigger genotoxicity, such as DNA damage, and can reduce genetic diversity. Field studies have also provided more direct evidence that EDCs contribute to the population decrease and biodiversity decline. Evolutionary toxicology and multigenerational toxicity tests have further demonstrated that EDCs can damage an organism's offspring and eventually likely lead to loss of evolutionary potential. Taken together, these results provide some basis for understanding the relationship between variety deterioration and EDC exposure. It is conceivable that there is a causal association between EDC exposure and variety deterioration of aquatic organisms.

Tributyltin toxicity in abalone (Haliotis diversicolor supertexta) assessed by antioxidant enzyme activity, metabolic response, and histopathology.

A toxicity test was performed to investigate the possible harmful effects of tributyltin (TBT) on abalone (Haliotis diversicolor supertexta). Animals were exposed to TBT in a range of environmentally relevant concentrations (2, 10 and 50 ng/L) for 30 days under laboratory conditions. TBT-free conditions were used as control treatments. The activity of antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD), and malondialdehyde (MDA), along with levels of haemolymph metabolites, and hepatopancreas histopathology were analyzed. The results showed that TBT decreased SOD activity, and increased POD level and MDA production in a dose-dependent way, indicating that oxidative injury was induced by TBT. Haemolymph metabolite measurements showed that TBT increased alanine and glutamate levels, and decreased glucose content, which suggested perturbation of energy metabolism. Elevated levels of acetate and pyruvate in the haemolymph indicated partial alteration of lipid metabolism. A decrease in lactate and an increase in succinate, an intermediate of the tricarboxylic acid (TCA) cycle, indicated disturbance of amino acid metabolism. Hepatopancreas tissues also exhibited inflammatory responses characterized by histopathological changes such as cell swelling, granular degeneration, and inflammation. Taken together, these results demonstrated that TBT was a potential toxin with a variety of deleterious effects on abalone.

Innate immune parameters and haemolymph protein expression profile to evaluate the immunotoxicity of tributyltin on abalone (Haliotis diversicolor supertexta).

The immunotoxicity of tributyltin (TBT) on marine gastropods has been comparatively little studied although risks to wildlife associated with this compound are well known. In this study, a 30-day trial was conducted to evaluate the immunotoxic effects on abalone (Haliotis diversicolor supertexta) by exposing a range of doses of TBT (0, 2, 10, and 50 ng/L). Innate immune parameters, including phagocytic ability (PA), lysozyme activity, phenoloxidase (PO) level and superoxide dismutase (SOD) activity were monitored at intervals of 5, 15 and 30 days. Haemolymph protein expression profile was also examined at the end of the experiment. The results showed that PA value, lysozyme activity and PO level significantly decreased compared with the controls (P < 0.05), which indicated that TBT exposure markedly suppressed non-specific immune competence. Exposure to TBT also caused variation in protein expression patterns of haemolymph. Among the protein spots of differential expressions, seven proteins from the haemolymph of TBT-treated abalone were successfully identified by MALDI-TOF-MS analysis. Three protein spots increased and were identified as carrier-like peptide, peroxidase 21 precursor and creatine phosphokinase. These proteins are believed to up-regulate in expression as a response to detoxification and antioxidative stress mechanisms. The other four protein spots that down-regulated in TBT-treated groups were identified as aromatase-like protein, protein kinase C, ceruloplasmin and microtubule-actin crosslinking factor 1, and these proteins play an important role in endocrine regulation and immune defense. Taken together, the results demonstrate that TBT impair abalone immunological ability and is a potential immune disruptor.

[Oxidative damages of long-term exposure to low level fullerenes (C60) in Carassius auratus].

To determine the potential effects of fullerenes (C60) on aquatic organism, larval Carassius auratus was exposed to low level C60 (0.04-1.0 mg x L(-1)) for 32 days. Then the oxidative damages in brain, liver and gill tissue of larval Carassius auratus were measured. The results showed that: compared to the control, the reduced glutathione (GSH) contents in all different tissues decreased significantly (p < 0.05), and the most serious inhibition of GSH with a 14.3% inhibition rate was found in the gill tissue of larval crucian exposed to 1 mg x L(-1) C60 aqueous suspension; whereas the superoxide dismutase (SOD) and catalase (CAT) activities in liver tissue, Na+ -K+ -ATPase activities in gill tissue were stimulated significantly (p < 0.05), and the maximal activity of them were 121.34% (exposed to 0.04 mg x L(-1) C60 aqueous suspension), 114.80% (exposed to 0.04 mg x L(-1) C60 aqueous suspension) and 348.59% (exposed to 0.20 mg x L(-1) C60 aqueous suspension) respectively than that of control. The experiment results indicated that oxidative damages induced by long-term exposure might play a role in the bio-toxicity of C60 to larval crucian.

[Flow injection biosensor based on the immobilized AChE].

A biosensor based on the flow injection system was constructed with the immobilized AChE from Scomberomorus niphonius (Curier) as identification element and a pH electrode as transducer. When phosphate buffer was used as carrier liquid, a good reproducibility (RSD = 1.427% , n=10) of the biosensor response was obtained after the substrate was injected repetitively. After an incubation time of 20 min, the calibration graph to methyl-parathion is linear (r = 0.9986) when its concentration ranges from 4.29 x 10(-10) mol x L(-1) to 4.29 x 10(-8) mol x L(-1) , and the detection limit is 1.3 x 10(-10) mol x L(-1). However, the sensitivity of this biosensor to methyl-parathion when using clean seawater as carrier liquid is not as good as that using phosphate buffer. But after preoxidation of methyl-parathion with NaClO as oxidant, the detection limit of the biosensor to methyl-parathion in seawater can be improve to 2.16 x 10(-7) mol x L(-1).