Long-term effects of di-octyl phthalate on the expression of immune-related genes in <Emphasis Type="Italic">Tegillarca granosa</Emphasis>

Di-octyl phthalate (DOP) is widely used as a plasticizer in the plastics industry. As a result, DOP is often found in marine water ecosystems where many species are exposed to it. Our objective was to evaluate the effect of long-term (14 d) DOP exposure (2.6, 7.8, or 31.2 mg/L) on the expression of immunerelated genes in Tegillarca granosa. The expression of small heat shock protein (sHSPs) and tissue inhibitor of metalloproteinase (TIMP) were highest in clams exposed to 31.2 mg/L DOP on days 7 and 14. The relative expression of Tg-ferritin, superoxide dismutase (SOD), and metallothionein (MT) increased initially then decreased as the concentration of DOP increased. The hemoglobin of T. granosa (Tg-HbI) exhibited two distinct expression patterns at two time points. Our results suggest that the immune response of T. granosa against DOP pollution varies depending on the dose. Additionally, we identified some immune-related genes that are promising candidates for biomarkers of DOP.     

Effect of hypoxia on the blood of large yellow croaker (Pseudosciaena crocea)

Large areas of hypoxic water have recently been reported in the East China Sea. It is hypothesized that hypoxia may be partially responsible for the decline of some fish stocks. We evaluated the effect of hypoxia on large yellow croaker (Pseudosciaena crocea). The fish were exposed to three concentrations of dissolved oxygen (DO; 1.5 mg/L and 2.0 mg/L, and 6.5 mg/L control). We collected blood after 6, 12, 24, 48, and 96 h exposure. There was a significant increase in red blood count, hematocrit, hemoglobin concentration, and mean corpuscular hemoglobin in the group exposed to 1.5 mg/L DO after 6 h or 12 h, and a delayed increase (only elevated after 48 h and 96 h) in these indices in the group exposed to 2.0 mg/L DO. Plasma glucose concentrations increased significantly in both hypoxic groups after 24 h. Furthermore, plasma lactate and lactate dehydrogenase activity increased significantly after the first 6 h exposure in both hypoxic groups. Our results suggest that large yellow croakers could not maintain the aerobic pathway and instead use anaerobic metabolism for survival when DO levels fall below 2.0 mg/L. We conclude that the occurrence of hypoxia (<2 mg/L DO) in the East China Sea could cause metabolic stress for large yellow croakers and may be partially responsible for the population decline of this species.     

Single or combined effects of dietary arabinoxylan-oligosaccharide and inulin on growth performance,gut microbiota,and immune response in Pacific white shrimp Litopenaeus vannamei

The single and synergistic effects of dietary arabinoxylan-oligosaccharide(AXOS) and inulin at different doses(2,4,and 8 mg/g diet) on survival,growth performance,gut microbiota,and immune response in Pacific white shrimp Litopenaeus vannamei were assessed.Singular application of either inulin or AXOS at doses of 4 mg/g diet showed the most stimulatory effects on the growth rate and gene expression levels of chitinase,cathepsin L,chymotrypsin,and extracellular signal-regulated kinase(ERK) in each single prebiotic feeding trial.Compared with single prebiotic treatments,simultaneous application of AXOS and inulin at 4 mg/g diet enhanced remarkably the growth parameters of shrimp and the expression of related genes(chitinase,cathepsin L,chymotrypsin ERK,myeloid differentiation factor88,and phenoloxidase) after 8-week feeding(P0.05).Additionally,gut microbiota analysis indicated the dietary supplementation with combined prebiotics increased significantly the bacterial community richness and relative abundance of Bacillus,Pseudomonas,Bacteriovorax,and Lactobacillus,and reduced the abundance of Vibrio,Rhodococcus,and Photobacterium in the digestive tract of L.vannamei.Compared with the single prebiotic treatment and the control,combined prebiotics supplementation boosted notably the survival rate and expression levels of immune-related genes in shrimp infected with Vibrio alginolyticus or white spot syndrome virus.Therefore,simultaneous application of AXOS and inulin shall have a great potential of dietary supplement in the culture of L.vannamei.     

三氯生对雌性斑马鱼肝胰脏凋亡相关基因表达的影响

【目的】研究三氯生(TCS)对雌性硬骨鱼类肝胰脏损伤的相关分子机制。【方法】采用半静态水体接触染毒法,将雌性斑马鱼(Danio rerio)暴露于0、0.017、0.034、0.068 mg/L的TCS溶液42 d,采用普通PCR和实时荧光定量PCR技术测定雌性斑马鱼肝胰脏凋亡相关基因(Bcl-2、p53、MDM2、Bax)的表达情况。【结果】0.017~0.068 mg/L组的雌性斑马鱼肝胰脏Bcl-2、MDM2和Bax基因的表达极显著下调(P<0.01),p53基因的表达极显著上调(P<0.01)。【结论】0.017~0.068 mg/L的TCS显著影响雌性斑马鱼肝胰脏凋亡相关基因的表达,促进雌性斑马鱼肝胰脏细胞凋亡的发生。     

Biochemical response of the mussel Mytilus coruscus (Mytiloida: Mytilidae) exposed to in vivo sub-lethal copper concentrations

Many aquatic organisms are negatively affected by exposure to high copper concentrations.We investigated the biochemical response of the mussel Mytilus coruscus(Mytiloida:Mytilidae) to copper exposure.In vivo bioassays using M.coruscus and different copper concentrations were conducted.The activity of six biomarkers,namely superoxide dismutase(SOD),catalase(CAT),acid phosphatase(ACP),alkaline phosphatase(AKP),glutamic-oxaloacetic transaminase(GOT) and glutamic-pyruvic transaminase(GPT) were measured.Survival rates decreased with increased copper concentrations and exposure times.The LC50 values at 48,72,and 96 h exposure were 0.48,0.37,and 0.32 mg/L,respectively.Within digestive glands,CAT activity increased with increasing Cu concentrations.The activity of AKP showed no significant change,while the remaining four enzymes showed decreasing activity with increasing Cu concentrations.Within the gills,AKP activity increased when the Cu concentration was 0.05 mg/L,but showed no significant changes at higher concentrations.Activity of CAT and ACP within gills tended to decrease with increasing Cu concentration.The activity of SOD and GPT decreased at an exposure concentration of 0.2 mg/L.GOT activity within gills decreased at 0.1 mg/L and increased at an exposure concentration of 0.2 mg/L.Within the adductor muscle,AKP activity increased at 0.05 mg/L but did not change at higher exposure concentrations.ACP activity within adductor muscle tissue showed no change,while activities of CAT,GOT and GPT decreased with increasing Cu concentrations.SOD activity within the adductor muscle tissue significantly decreased at the 0.02,0.05 and 0.2 mg/L exposure concentrations.Our results show tissue specific differences for the six biomarkers in for M.coruscus.Our findings provide the basis for the establishment of reference activity levels against which biomarker changes can be estimated,and are essential preliminary steps in development of in vivo bioassays.     

Effects of waterborne Fe(II) on juvenile turbot Scophthalmus maximus: analysis of respiratory rate, hematology and gill histology

The concentration of Fe(Ⅱ) is high in some groundwater supplies used in turbot culture,and the toxicity of waterborne Fe(Ⅱ) is unknown.We investigated the stress responses of juvenile turbot,Scophthalmus maximus,exposed to Fe(Ⅱ) of different concentrations (0.01,0.05,0.1,0.5,1,and 2 mg/L) for 1,7,14,and 28 d,under the same ambient conditions of other parameters.Changes in respiratory rate,hematological parameters,and gill structure were determined.The results show that waterborne Fe(Ⅱ) did not cause severe hematological perturbation to turbot.A low-medium Fe(Ⅱ) concentration (lower than 0.1 mg/L) could boost the respiratory rate,and caused no or very limited damage to fish.A high Fe(Ⅱ) concentration (0.1 mg/L or higher),however,caused gill damage,such as vacuoles in branchial lamellae,epithelial necrosis,and hypertrophy of epithelial cells,and even death after extended exposure time.Therefore,excess waterborne Fe(Ⅱ) and long-term exposure to Fe(Ⅱ) could be responsible for poor growth and high mortality of turbot in culture.The concentration of waterborne Fe(Ⅱ) in turbot culture should be kept below 0.1 mg/L.     

Effects of a low-radiotoxicity uranium salt(uranyl acetate) on biochemical and hematological parameters of the catfish,Clarias gariepinus

Specimens of Clarias gariepinus were treated with lethal(70,75,80,85,90,and 95 mg/L) and sub-lethal concentrations(8,12 and 16 mg/L) of uranyl acetate,a low-radiotoxicity uranium salt. The LC 50 value was registered as 81.45 mg/L. The protein and glycogen concentrations in liver and muscles were decreased in the fish exposed to sub-lethal concentrations. The red blood cell(RBC) and white blood cell(WBC) counts,haemoglobin(Hb) concentration and haematocrit(Hct) values were decreased. Different blood indices like mean corpuscular volume(MCV),mean corpuscular haemoglobin(MCH) and mean corpuscular haemoglobin concentration(MCHC) were negatively affected. Level of plasma glucose was elevated whereas protein was decreased. The level of calcium concentration(Ca) was declined in the blood of exposed fish whereas magnesium(Mg) remains unchanged. The activity level of glutamic-oxaloacetic transaminase(GOT) and glutamic-pyruvic transaminase(GPT) was elevated in exposed fish. These effects were more pronounced in the last period of exposure and in higher concentrations. Results of the present study indicate that uranyl acetate has adverse effects on C larias gariepinus and causes changes in the biochemical and hematological parameters of the fish.     

湛江港区底泥悬浮物对凡纳滨对虾仔虾成活的影响

模拟吹填、疏浚等海上施工过程所产生的底泥悬浮物浓度的变化规律,探讨不同底泥悬浮物浓度下对凡纳滨对虾仔虾成活影响。结果表明:海水中底泥悬浮物浓度超过10mg/L,持续时间超过12h时,将对凡纳滨对虾成活率产生影响,随着悬浮物实验浓度的递加,仔虾的死亡率从13.33%增至96.67%;超过80mg/L,且持续时间超过48h,将对凡纳滨对虾产生严重影响,甚至导致全部仔虾的死亡;悬浮物对凡纳滨对虾的12h、24h、36h和48h半致死量(LC50)分别为54.56、40.29、25.8和19.18mg/L。     

苯酚和十二烷基苯磺酸钠对奥尼罗非鱼的急性毒性及安全评价

用苯酚和十二烷基苯磺酸钠对奥尼罗非鱼进行急性毒性实验,以评价其在水环境中对奥尼罗非鱼的影响。研究表明:苯酚对奥尼罗非鱼的24、48、96 h的LC50分别为40.33、34.23、28.07 mg/L,十二烷基苯磺酸钠分别为10.06、9.14、8.48 mg/L;苯酚对奥尼罗非鱼SC及最大容许浓度MPC分别为2.807、0.281 mg/L,十二烷基苯磺酸钠对奥尼罗非鱼SC为0.848 mg/L,最大容许浓度MPC为0.085 mg/L。     

Effects of heavy metals (Pb2+ and Cd2+) on the ultrastructure, growth and pigment contents of the unicellular cyanobacterium Synechocystis sp. PCC 6803

The unicellular cyanobacterium Synechocystis sp. PCC 6803, a model organism known for its unique combination of highly desirable molecular genetic, physiological and morphological characteristics, was employed in the present study. The species was cultured in BG11 liquid medium contained various initial concentrations of Pb2+ and Cd2+ (0, 0.5, 1, 2, 4, 6 and 8 mg/L). The experiment was conducted for six days and the metal induced alterations in the ultrastructure, growth and pigment contents were assessed. Alterations in the ultrastructure of the Synechocystis sp. PCC 6803 ceils became evident with the increased (>4 mg/L Pb2+) metal concentration. The photosynthetic apparatus (thylakoid membranes) were found to be the worst affected. Deteriorated or completely destroyed thylakoid membranes have made large empty spaces in the cell interior. In addition, at the highest concentration (8 mg/L pb2+), the polyphosphate granules became more prominent both in size and number. Despite the initial slight stimulations (0.2, 3.8 and 6.5% respectively at 0.5, 1 and 2 mg/L Pb2+), both metals inhibited the growth in a dose-dependent manner as incubation progressed. Pigment contents (chlorophyll a, βcarotene and phycocyanin) were also decreased with increasing metal concentration. Cells exposed to 6 mg/L Pb2+, resulted in 36.56, 37.39 and 29.34% reductions of chlorophyll a, β carotene and phycocyanin respectively over the control. Corresponding reductions for the same Cd2+concentrations were 57.83, 48.94 and 56.90%. Lethal concentration (96 h LC50) values (3.47 mg/L Cd2+ and 12.11 mg/L Pb2+) indicated that Synechocystis sp. PCC 6803 is more vulnerable to Cd2+ than Pb2+.     

Effects of a low-radiotoxicity uranium salt (uranyl acetate) on biochemical and hematological parameters of the catfish, <Emphasis Type="Italic">Clarias gariepinus</Emphasis>

Specimens of Clarias gariepinus were treated with lethal (70, 75, 80, 85, 90, and 95 mg/L) and sub-lethal concentrations (8, 12 and 16 mg/L) of uranyl acetate, a low-radiotoxicity uranium salt. The LC 50 value was registered as 81.45 mg/L. The protein and glycogen concentrations in liver and muscles were decreased in the fish exposed to sub-lethal concentrations. The red blood cell (RBC) and white blood cell (WBC) counts, haemoglobin (Hb) concentration and haematocrit (Hct) values were decreased. Different blood indices like mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were negatively affected. Level of plasma glucose was elevated whereas protein was decreased. The level of calcium concentration (Ca) was declined in the blood of exposed fish whereas magnesium (Mg) remains unchanged. The activity level of glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) was elevated in exposed fish. These effects were more pronounced in the last period of exposure and in higher concentrations. Results of the present study indicate that uranyl acetate has adverse effects on Clarias gariepinus and causes changes in the biochemical and hematological parameters of the fish.     

Molecular Characterization,Tissue Distribution and Localization of Larimichthys crocea Kif3a and Kif3b and Expression Analysis of Their Genes During Spermiogenesis

KIF3A and KIF3B are two N-terminal motor proteins belonging to the kinesin-II superfamily that play essential roles in spermiogenesis. To understand the roles played by KIF3 A/3B during spermatogenesis of large yellow croaker Larimichthys crocea, we studied the testis characteristics at different developmental stages of L. crocea, and determined the spatiotemporal expression patterns of kif3a and kif3b during spermiogenesis. Quantitative real-time PCR(qR T-PCR) showed that the overall trends of kif3 a/3 b m RNA abundance during testis development are similar. From stage II to stage V, kif3a/3b m RNA abundances first increased and then fell after reaching a peak at stage IV. Interestingly, the m RNA abundances of both genes at stage V were higher than those at stages II and III. In addition, it is worth of noting that kif3 b m RNA abundance was higher than that of kif3a at all stages. Fluorescence in situ hybridization results revealed that kif3a/3b m RNA abundance dynamics were consistent with the migration of mitochondria, the deformation of nucleus, and the formation of tail. The m RNA hybridization signals of both genes first appeared either around the nuclear periphery or on the side of the nuclei, then appeared at one side of nuclei, and finally were mainly on the tail during spermiogenesis. Our findings contributed to better understanding the molecular mechanisms of spermiogenesis in fish; and suggested that KIF3A and KIF3B may participate in the intracellular transport of mitochondria, nuclear deformation, and the formation of tail during the spermiogenesis in L. crocea.     

水体中NH3-N对建鲤非特异性免疫功能的影响

用 0 .1、0 .5、1.0、2 .0和 5.0 mg/ L NH3- N分别刺激建鲤 10 d和 2 0 d后 ,测定了建鲤非特异性免疫指标 ,估测不同浓度的 NH3- N对建鲤非特异性免疫指标的影响。 0 .1、0 .5mg/ L的 NH3- N对建鲤NBT阳性细胞、溶菌酶活性无影响 ,1.0 mg/ L的 NH3- N可使 NBT阳性细胞数和溶菌酶活性降低 ,而2 .0和 5.0 mg/ L则使 NBT阳性细胞数和溶菌酶活性显著下降 ( P<0 .0 5)。这些结果表明水体中 0 .1、0 .5mg/ L的 NH3- N对建鲤非特异性免疫功能无影响 ,1.0 mg/ L的 NH3- N略有影响 ,而 2 .0和 5.0mg/ L的 NH3- N则明显降低了建鲤的非特异性免疫功能     

波纹龙虾胚胎对五种生态因子的适应性

【目的】研究波纹龙虾(Panulirus homarus)胚胎对生态因子的耐受能力,为龙虾繁殖提供数据。【方法】采用封闭静水实验方法和常规生物急性毒性实验法。在温度(30±0.5)℃,盐度30,pH(8.10±0.1)和溶解氧(DO)为(5.0±0.5)mg/L条件下,分别进行温度、盐度、pH的骤变和渐变对波纹龙虾胚胎存活影响研究;根据急性毒性预实验结果设置等对数间距浓度值,进行氨氮和亚硝酸盐氮对波纹龙虾胚胎的急性毒性实验。【结果与结论】波纹龙虾胚胎发育的温度、盐度和pH耐受范围分别为7~36℃、15~45和5.8~9.4;波纹龙虾胚胎适宜温度为15~30℃,适宜盐度为30~35,适宜pH为7.0~8.5;氨氮和亚硝酸盐氮毒性效应与浓度和暴露时间呈正相关。氨氮和亚硝酸盐氮暴露24~96 h,波纹龙虾胚胎存活率组间存在显著性差异(P<0.05)。氨氮对波纹龙虾胚胎24、48、72和96 h的半致死浓度(LC₅₀)分别是180.46、61.11、41.87、26.58 mg/L,安全浓度(SC)为2.66 mg/L;亚硝酸盐氮对波纹龙虾胚胎24、48、72和96 h的LC₅₀分别是839.50、423.75、214.48、135.41 mg/L,SC为13.54 mg/L。     

Effects of nitrogen and phosphorus on the growth of <Emphasis Type="Italic">Levanderina fissa</Emphasis>: How it blooms in Pearl River Estuary

Effects of nitrogen (N) and phosphorus (P) from different sources and at different concentrations on the growth of Levanderina fissa (= Gyrodinium instriatum) were studied in laboratory conditions. The findings might explain the recurrent blooms of this species in Pearl River Estuary, China. Results showed that nutrient limitation significantly inhibited the growth of L. fissa. The values of specific growth rate (μ _max) and half-saturation nutrient concentration (K _S) were 0.37 divisions/d and 8.49 μmol L^?1 for N, and 0.39 divisions/d and 1.99 μmol L^?1 for P, respectively. Based on K _S values, dissolved inorganic N level in PRE was sufficient to support the high proliferation of L. fissa, while dissolved inorganic P concentration was far lower than the minimum requirement for its effective growth. L. fissa was not able to utilize dissolved organic N (DON) compounds such as urea, amino acids, and uric acid. However, it grew well by using a wide variety of dissolved organic P (DOP) sources like nucleotides, glycerophosphate, and 4-nitrophenylphosphate. The results from this study suggested that the ability in DOP utilization of L. fissa offers this species a competitive advantage in phytoplankton communities. The high level and continuous supply of DIN, enrichment of DOP, together with warm climate and low salinity in the Pearl River Estuary provided a suitable nutrient niche for the growth of L. fissa, and resulted in the recurrent blooms in the estuary.     

THE AVAILABILITY OF DISSOLVED ORGANIC PHOSPHORUS COMPOUNDS TO MARINE PHYTOPLANKTON

The availability of three dissolved organic phosphorus (DOP) compounds as nutrient sources for experimentalcultare of three algae was studied. Results indicated that these compounds could be utilized byalgae, and that dissolved inorganic phosphorus (DIP) was first to be uptaken when various forms ofphosphorus (DIP and DOP) co-existed. Dicrateria zhanjiangensis' uptake of sodium glycerophosphatewas faster than that of D-ribose-5-phosphate. The increase of sodium glycerphosphate had little effecton the maximum uptake rate(V_(max)) of Chlorella sp., but increased the semisaturation constant(K_s) remarkably;the photosynthesis rates(PR) of Dicrateria zhanjiangensis and Chlorella sp. were rarely affected byusing various forms of phosphorus in the culture experiments. The possible DOP pathways utilizedby algae are discussed.     

Effect of cadmium on the defense response of Pacific oyster Crassostrea gigas to Listonella anguillarum challenge

Heavy metal pollution can affect the immune capability of organisms.We evaluated the effect of cadmium(Cd) on the defense responses of the Pacific oyster Crassostrea gigas to Listonella anguillarum challenge.The activities of several important defensive enzymes,including superoxide dismutase(SOD),glutathione peroxidase(GPx),acid phosphatase(ACP),Na+,K+-ATPase in gills and hepatopancreas,and phenoloxidase-like(POL) enzyme in hemolymph were assayed.In addition,the expression levels of several genes,including heat shock protein 90(HSP90),metallothionein(MT),and bactericidal/permeability increasing(BPI) protein were quantified by fluorescent quantitative PCR.The enzyme activities of SOD,ACP,POL,and GPx in hepatopancreas,and the expression of HSP90 were down-regulated,whereas GPx activity in the gill,Na+,K+-ATPase activities in both tissues,and MT expression was increased in Cdexposed oysters post L.anguillarum challenge.However,BPI expression was not significantly altered by co-stress of L.anguillarum infection and cadmium exposure.Our results suggest that cadmium exposure alters the oysters’ immune responses and energy metabolism following vibrio infection.     

Acute toxicity effects of perfluorooctane sulfonate on sperm vitality,kinematics and fertilization success in zebrafish

Perfluorooctane sulfonate(PFOS) has emerged as one of the most concerning contaminants in recent years.This study aimed to investigate the acute toxicity effect of PFOS on sperm viability,kinematics and fertilization success in zebrafish(Danio rerio).Sperm were activated in aqueous media containing a range of PFOS concentrations(0,0.09,0.9 and 9 mg/L).Viabilities and kinematics of the sperm exposed to different PFOS treatments were assessed via computer-assisted sperm analysis(CASA) at 20,40,60,and 80 s after activation.PFOS exposure decreased the percentage of motile sperm,the curvilinear velocity(VCL),and the mean angular displacement(MAD) of spermatozoa,but showed no influence on the straightline velocity(VSL) or the angular path velocity(VAP).Furthermore,a significant decrease in fertiUzation success was observed in spermatozoa that were exposed to 0.9 mg/L PFOS or more.These findings indicate that PFOS pollution in natural aquatic environment may be a potential threaten to successful reproduction offish.     

苯酚对奥尼罗非鱼非特异性免疫指标的影响

采用水体中常见污染物——苯酚对奥尼罗非鱼进行刺激,研究不同浓度苯酚对奥尼罗非鱼非特异性免疫功能的影响。奥尼罗非鱼分别暴露于0.005、0.025、0.125、0.625、3.125 mg/L等5个浓度的苯酚中8周,每两周采集抗凝血液和血清,用于检测非特异性免疫指标。结果表明:暴露于低浓度苯酚组(0.005 mg/L和0.025 mg/L)的奥尼罗非鱼NBT(氯化硝基四氮唑蓝)阳性细胞数等非特异性免疫指标相对于对照组无显著性差异(P>0.05),中浓度苯酚组(0.125 mg/L和0.625 mg/L)和高浓度苯酚组(3.125mg/L)对罗非鱼非特异性免疫指标的影响存在显著的时间效应和剂量效应(P<0.05),可减少NBT阳性细胞数、抑制超氧化物歧化酶活力和抗菌活力;促使溶菌酶活力和溶菌酶含量先升后降。表明中高浓度苯酚组对奥尼罗非鱼具有明显的免疫毒性。