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1.
Nano-sized zinc oxide (nZnO) particles are one kind of the most commonly used metal oxide nanoparticles (NPs). This study compared the cytotoxic and embryotoxic effects of three increasing sized ZnO particles (? 30 nm, 80-150 nm and 2 μm) in the flounder gill (FG) cells and zebrafish embryos, and analyzed the contribution of size, agglomeration and released Zn2+ to the toxic effects. All the tested ZnO particles were found to be highly toxic to both FG cells and zebrafish embryos. They induced growth inhibition, LDH release, morphological changes and apoptosis in FG cells in a concentration-, size- and time-dependent manner. Moreover, the release of LDH from the exposed FG cells into the medium occurred before the observable morphological changes happened. The ultrasonication treatment and addition of serum favored the dispersion of ZnO particles and alleviated the agglomeration, thus significantly increased the corresponding cytotoxicity. The released Zn2+ ions from ZnO particles into the extracellular medium only partially contributed to the cytotoxicity. All the three sizes of ZnO particles tested induced developmental malformations, decrease of hatching rates and lethality in zebrafish embryos, but size- and concentration- dependent toxic effects were not so obvious as in FG cells possibly due to the easy aggregation of ZnO particles in freshwater. In conclusion, both FG cells and zebrafish embryos are sensitive bioassay systems for safety assessment of ZnO particles and the environmental release of ZnO particles should be closely monitored as far as the safety of aquatic organisms is concerned.  相似文献   

2.
Overthelastseveraldecades,harmfulalgalblooms(HABs)havebecomeaseriousenvironmental problem in many parts of the world. A rapid and accurate detection process for HAB algae has yet to be developed. Heterosigma akashiwo is one of the most important HABs species in China. The objective of this study was to develop an immunologic technique that can rapidly and sensitively count H. akashiwo cells. Five HABs species (Alexandrium catenella, Thalassiosira sp., Cryptomonas sp., Alexandrium tamarense and Symbiodinium sp.,) were used in this study to evaluate the analysis process we developed. A polyclonal antibody with high titers against H. akashiwo was obtained by injecting H. akashiwo cells into rabbits. Immuno-magnetic beads (IMB) were produced via conjugated polyclonal antibodies with magnetic beads and applied to isolate and count H. akashiwo cells from the culture. Results show that 66.7%-91.6% of the cells were captured from unialgal culture by IMBs, and only 5.3%-12.5% of the four other HAB microalgae species were captured, indicating that the constructed IMBs combined specifically with the H. akashiwo cells. At the same time, flow cytometry (FCM) sorting was exploited to screen H. akashiwo cells after labeling with FITC conjugated polyclonal antibodies. Using the FCM technique, 91.7% of the targeted cells were sorted out from mixed microalgae samples in just a few minutes. These results indicate that both antibody-involved IMB and antibody-based FCM techniques are highly effective at detecting and quantifying HAB species. These techniques, especially immuno-magnetic separation, have low associated cost, and are fast and simple processes compared with other techniques currently in use.  相似文献   

3.
A continuous marine fish cell line RSBF(i.e.Red Sea Bream Fin)was utilized to screen the cytotoxicity and genotoxicity of polyethylenimine(PEI)and nickel cholride(NiCl2)in this study on the deleterious effects of aquatic genotoxins on fish.At the 0.01 to 1μgml concentration tested,PEI had acute toxicity to the treated RSBF cells(IC50=1.12,0.92,0.88 and 0.64μg/ml PEI for time 0 h,24 h,48 h and 72 h after treatment,respectively)and markedly inhibited their proliferation in a dose-dependent manner.At the 0.001 to 5 μmol/L concentration tested,NiCl2 posed no acute toxicity but significantly stimulated their growth(107?214?of control).Random amplified polymorphic DNA(RAPD)technique was used to detect the genotoxic effects of PEI and NiCl2 by comparing the RAPD banding patterns of the control and treated cells.RAPD analysis indicated that at the concentrations tested,PEI was more genotoxic than NiCl2 to RSBF cells;that there was a slight dose-dependent response in the genotoxic effect of PEI bue not NiCl2;and that RAPD technique might provide a sensitive,non-specif-ic gentoxic endpoint.And the potent cytotoxicity and genotoxicity of PEI on fish cells showed that we should be cautious in utilizing it as gene vector in fish gene transfer and human gene therapy.  相似文献   

4.
A new kinetic spectrophotometric method has been developed for the determination of iron (Ⅲ). The method is based on the catalytic effect of iron (Ⅲ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The advantages of the proposed method are that it is sensitive, accurate, rapid, inexpensive, can be operated under room temperature and has a large determination concentration range compared to other techniques. The obtained optimum conditions are pH 3.15, RAWL (200 mgL-1) 5.00mL, Potassium periodate solution (0.01 molL-1) 0.30mL, phenanthroline (0.02molL-1) 1.00mL, reaction temperature 25℃ and reaction time 7 miu. With this method iron could quantitively be determined in the range 0.00-0.02 mgL-1, the detection limit being 4.10×10-10mL-1. The relative standard deviations (RSD) in five replicate determinations for 3 μgL-1 and 5μgL-1 iron (Ⅲ) are 3.1% and 1.9%, respectively. The method has been applied to the determination of iron (Ⅲ) in tap water samples and seawater samples (from the South China Sea), the recovery rates being 98.0% and 100.5%, respectively.  相似文献   

5.
A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L~(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg~(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg~(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues.  相似文献   

6.
The Cytotoxic Constituents from Marine-derived Streptomyces 3320^#   总被引：2，自引：0，他引：2  
The present work studies the chemical constituents from marine-derived streptomyces 3320^# and their antitumor activities. The n-BuOH extract of the ferment broth of 3320^# was chromatographed on silica gel, Sephadex LH-20, ODS columns and HPLC to separate the compounds with antitoumor activities. Their structures were identified using IR, UV, NMR, MS spectroscopic techniques and compared with published data. The antitumor activities of the isolates were assayed using SRB method and flow cytometry assay, accompanied with the morphological observation of the cells under light micro- scope against mammalian tsFT210 cells. Ten compounds, cyclo-（Ala-Leu） 1, cyclo-（Ala-Ile） 2, cyclo-（Ala-Val） 3, cyclo- （Phe-Pro） 4, cyclo-（Phe-Gly）5, cyclo-（Leu-Pro）6, 1-methyl-1, 2, 3, 4-tetrahydro-β-carboline-3-carboxylic acid 7, N-（4- hydroxyphenethyl） acetamide 8, 4-methyoxy-l-（2-hydroxy） ethylbenzene 9 and uridine 10, were isolated from the ferment broth of streptomyces 3320^# . Among them, compounds 6, 7, 8 and 10 showed potent cytotoxicity against the tsFT210 cell with the IC50 values of 3.6, 7.2, 5.2 and 1.6 mmol L-1, respectively. Compounds 8, 10 also exhibited apoptosis inducing activity under 2.0 mmol L-1. Compounds 6, 7, 8 and 10 are the principle bioactive constituents responsible for the antitumor activities of marine streptomyces 3320^#. Compound 7 was isolated from this species for the first time.  相似文献   

7.
In situ loop-mediated isothermal amplification (in situ LAMP) combines in situ hybridization and loop-mediated isothermal amplification (LAMP) techniques for chromosomal localization of DNA sequences. In situ LAMP is a method that is generally more specific and sensitive than conventional techniques such as fluorescence in situ hybridization (FISH), primed in situ labeling (PRINS), and cycling primed in situ labeling (C-PRINS). Here, we describe the development and application of in situ LAMP to identify the chromosomal localization of DNA sequences. To benchmark this technique, we successfully applied this technique to localize the major ribosomal RNA gene on the chromosomes of the Zhikong scallop (Chlamys farreri).  相似文献   

8.
ＩＮＴＲＯＤＵＣＴＩＯＮＡｃｃｕｍｕｌａｔｅｄｅｖｉｄｅｎｃｅｓｓｕｇｇｅｓｔｅｄａｃｌｏｓｅｃｏｒｒｅｌａｔｉｏｎｂｅｔｗｅｅｎｎｅｏｐｌａｓｔｉｃｄｉｓｅａｓｅｏｆａｑｕａｔｉｃｏｒ ｇａｎｉｓｍｓａｎｄｔｈｅｉｎｃｒｅａｓｉｎｇｒｅｌｅａｓｅｏｆｇｅｎｏｔｏｘｉｎｓｂｙａｎｔｈｒｏｐｏｇｅｎｉｃａｃｔｉｖｉｔｉｅｓｉｎｔｏａｑｕａｔｉｃｅｎｖｉｒｏｎｍｅｎｔ(Ｍｉｘ ,1 986;Ｇａｒｄｎｅｒｅｔａｌ.,1 991 ;ＧＥＳＡＭＰ ,1 991 ) .Ｉｔｈａｓ,ｔｈｅｒｅｆｏｒｅ,ｂｅｃｏｍｅｎｅｃｅｓｓａｒｙｔｏｅ…  相似文献   

9.

A spectral method to investigate the effect of Fe3+, Fe2+ on the thermostability of phycocyanin (PC) ofSpirulina maxima showed that iron ions provent decrease of visible light absorbance and fluorescence intensity of PC. Increase in denaturation temperature caused by Fe3+ was observed by the micro-differential scanning calorimetric method. All results showed iron ions maintain the aggregation stability of the PC. The absorption spectrum of phycocyanobilin (PCB, a prosthetic group of PC) with Fe3+ in chloroform was quite different from that of free PCB.

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10.
A new isobenzofuran derivative (1) was isolated from the marine Streptomyces sp. W007 and its structure was determined through extensive spectroscopic analyses, including 1D-NMR, 2D-NMR, and ESI-MS. The absolute configuration of compound 1 was determined by a combination of experimental analyses and comparison with reported data, including biogenetic reasoning, J-coupling analysis, NOESY, and 1H-1HCOSY. Compound 1 exhibited no cytotoxicity against human cells of gastric cancer BGC-823, lung cancer A549, and breast cancer MCF7.  相似文献   

11.
Turbot(Scophthalmus maximus L.) reddish body iridovirus(TRBIV) was propagated in turbot fin cells(TF cells) and inactivated as the TRBIV vaccine with its protection efficiency evaluated in this study.TF cells were cultured in 10% bovine calf serum(BCS)-containing MEM medium(pH7.0) at 22℃,in which TRBIV propagated to a titer as high as 105.6 TCID50 mL-1.The TRBIV was inactivated with 0.1% formalin and formulated with 0.5% aluminum hydroxide.The inactivated vaccine caused neither cytopathogenic effect(CPE) on TF cells nor pathogenic effect on turbots.After being administered with the vaccine twice via muscle injection,the turbot developed high-tittered TRBIV neutralizing antibodies in a dose-dependent manner.The vaccine protected the turbot from dying with an immunoprotection rate of 83.3% as was determined via subcutaneous vaccination in the laboratory and 90.5% via bath vaccination in turbot farms,respectively.The inactivated vaccine was very immunogenic,efficiently preventing tur-bot from death.It holds the potential of being applied in aquaculture.  相似文献   

12.
The gene ble from Streptoalloteichus hindustanus is widely used as a selective antibiotic marker. It can control the phleomycin resistance, and significantly increase the tolerance of hosts to zeocin. The unicellular marine microalga Nannochloropsis oculata is extremely sensitive to zeocin. We selected ble as the selective marker for the genetic transformation of N. oculata. After the algal cells at a density of 2×107 cells mL?1 was digested with 4% hemicellulase and 2% driselase for 1 h, the protoplasts accounted for 90% of the total. The ble was placed at the downstream of promoter HSP70A-RUBS2 isolated from Chlamydomonas reinhardtii, yielding a recombinant expression construct pMS188. The construct was transferred into the protoplasts through electroporation (1 kV, 15 μS). The transformed protoplasts were cultured in fresh f/2 liquid medium, and selected on solid f/2 medium supplemented with 500 ng mL?1 zeocin. The PCR result proved that ble existed in the transformants. Three transformants had been cultured for at least 5 generations without losing ble. Southern blotting analysis showed that the ble has been integrated into the genome of N. oculata. The ble will serve as a new dominant selective marker in genetic engineering N. oculata.  相似文献   

13.
Tropical glaciers are extremely sensitive to a warming climate. In this paper, the evolution of the remaining tropical glaciers in Australasia(Irian Jaya, Indonesia) during the period 1988-2015 was quantified. Landsat series images, a digital elevation model from SRTM, and previously published data were used. Estimated total glacier area in 1988, 1993, 1997 and 2004 was 3.85 km2±0.13 km2, 3.01 km2±0.08 km2, 2.49 km2±0.07 km2 and 1.725 km2 ±0.042 km2, respectively. Only 0.58 km2±0.016 km2 glacierized area remained in 2015 in Puncak Jaya, which is about 84.9% loss in just 27 years. If this rate continued, the remaining tropical glaciers in Australasia would disappear in the 2020 s. Timeseries analysis of climate variables showed significant positive trends in air temperature(0.009°C per year) and relative humidity(0.43% per year) but no considerable tendency was observed for precipitation. Warming climate together with mining activities would accelerate loss of glacier coverage in this region.  相似文献   

14.

The short term (hourly scale) variability of heterotrophic prokaryote (HP) vertical distribution and respiratory activity, was investigated in the north-western (NW) Mediterranean Sea. HP vertical distribution was determined on board by flow cytometry analysis of seawater samples collected by series of CTD casts. Cell counts and viability were determined for all samples. HP respiratory rates were determined later in the laboratory from filtered seawater samples (23 dm3) from 300–1 150-m depth. The average cell viability was 94.8%±2.2% (n=240). There was no accumulation of dead cells, due to quick decay of damaged cells. In the epipelagic layer, three HP groups were distinguished, two (HNA1, HNA2) whose cells exhibited a high nucleic acid content and one (LNA) with low nucleic acid content cells. HNA2 was most populated at 50 m but not detected at 90 m and below, presumably aerobic anoxygenic photoheterotrophic bacteria (AAPs). The variability in HP abundance was mainly confined in the upper 80 m. A few secondary peaks of HP abundance were observed (80–150 m) in connection with abundance troughs in the surface layer. HP cells were continuously present in a wide layer around 500 m (mean 191×103 cells/cm3). Below this layer, HP abundance randomly exhibited peaks, coupled to respiratory rate peaks. The HP abundance and variability in the water column was suppressed during a strong wind event. The observed sporadic variability was tentatively interpreted through a pulsed carbon-export mechanism induced by the microorganism production of dissolved polysaccharides, followed by flocculation and rapid sinking. This mechanism would thus contribute to (i) preventing organic matter accumulation in the epipelagic layer, (ii) seeding the water column with live HP cells, and (iii) supplying the aphotic water column with fresh and labile organic matter. This important vertical flux mechanism needs further observations and modelling.

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15.
A cell line,SHK,was derived from the kidney of spotted halibut Verasper variegates.The cell line was subcultured more than 40 passages in minimum essential medium(MEM)supplemented with fetal bovine serum(FBS)and 10 ng ml-1 basic fibroblast growth factor(bFGF).Cell morphology from primary culture and subculture was observed continuously by microscopy.The SHK cell line consisted predominantly of fibroblast-like cells.The cell line was able to grow between 20℃ and 30℃ with the optimum growth at 24℃ and with a reduced growth between 12℃ and 20℃.The growth rate of the cells increased as the proportion of FBS increased from 10% to 20% at 28℃ with optimum growth at the concentration of 20%.The doubling time of the cells was determined to be 44.8 h.Chromosome analysis revealed that 52% of the SHK cells maintained a normal diploid chromosome number (2n=46).The cells were successfully transfected with green fluorescent protein(GFP)reporter plasmids and the expression of GFP gene in the cells indicated the possible utility of the cells in gene expression studies.The cells were infected by lymphosystis disease virus(LCDV)and found to be susceptible to the virus in cytopathic effect(CPE)observation.The infection was confirmed by PCR and electron microscopy experiments,which proved the existence of the viral particles in the cytoplasm of the virus-infected cells.  相似文献   

16.
Vibrio harveyi cells (dose—<103 cells mL−1) and extracellular products (ECP; >25 μmg mL−1 of total protein concentration) destroyed haematopoietic cultures of Nephrops norvegicus within 24 h of exposure. Cytopathic effects (CPE) started after 4h of exposure to the bacterial cells, with some granularity in the cytoplasm, mostly in cells in the outer periphery of the explant growth. At the end of the infection, a considerable number of nuclei remained attached to the substrate, apparently unaffected. Following exposure to ECP, initial deterioration was observed at 2 h with the presence of granularity in the cytoplasm of<20% cells, and few cells displayed small vacuoles around the nuclei. Parallel results were obtained using whole animal experiments, with V. harveyi cells being lethal to nephrops within 24 h.  相似文献   

17.
Edwardsiella tarda is a major pathogen in aquatic environments that can cause heavy economic losses. An improved method for quick and accurate detection of E. tarda by loop-mediated isothermal amplification (LAMP) with two additional loop primers was developed by targeting the EsrB gene (EsrB-LAMP). In this method, the Mg 2+ concentration, reaction temperature, and reaction time were optimized to 8 mmol/L, 61°C, and 40 min, respectively. The detection limit with the EsrB gene was as low as 10 copies, which is 100 times more sensitive than that of conventional polymerase chain reaction (PCR). The EsrB-LAMP assay was shown more sensitive and rapid than previously reported LAMP assays targeting the hemolysin gene (hemolysin-LAMP) for detection of E. tarda. The EsrB-LAMP was also highly specific to E. tarda and had no cross-reaction with 13 other strains of bacteria. The assay can be carried out in a simple heating device and the EsrB-LAMP products can be visually detected by adding fluorescent dye to the reaction mixture. Taken together, the improved EsrB-LAMP diagnostic protocol has the potential for detection of E. tarda from indoor and outdoor samples.  相似文献   

18.
A new kinetic spectrophotometric method has been developed for the determination of vanadium (V). The method is based on the catalytic effect of vanadium (V) on the oxidation of weak acid brilliant blue dye (RAWL) by KBrO3 using the citric acid as activation reagent. The obtained optimum conditions are: c (RAWL) = 1×10−4 molL−1, c (KBrO3) = 3×10−2 molL−1, c (citric acid) = 9×10−3 molL−1, pH = 2.50, the reaction time being 7.0 min and the temperature being 25.0°C. Under the optimum conditions, the proposed method allows the determination of vanadium (V) in the range of 0–70.0 ng mL−1 and the detection limit is down to 0.407 ng mL−1. For standard vanadium (V) solution determination, the recovery efficiency is in the range of 98.5%–102% and the RSD ranges from 0.76%–1.25%. Moreover, it is demonstrated that most cations and anions do not interfere with the determination of vanadium (V) under the analytical condition. The new method was successfully applied in the determination of vanadium (V) in fresh water and seawater samples with satisfactory results. Vanadium (V) in the seawater samples from Qingdao offshore was determined using the method and the distribution of vanadium (V) was mapped. Compared with other instrumental analytical methods, the proposed method shows good selectivity, sensitivity, simplicity, lower cost and rapidity. It can be employed on shipboard easily.  相似文献   

19.
A new kinetic-spectrophotometric method is proposed for the determination of copper （ Ⅱ ）. The method is based on the catalytic effect of copper （ Ⅱ ） on the oxidation of weak acid brilliant blue dye （RAWL） by hydrogen peroxide. The copper （ Ⅱ ） can be determined spectrophotometrically by measuring the decrease of absorbance of RAWL at λ = 626 nm using the fix-time method. The optimum reaction conditions are as follows： pH 7.20, buffer solution NaOH-KH2PO4, RAWL （200 mgL-1） 5.00 mL, H2O2 （30%） 0.50 mL, reaction temperature 80 ？？ and reaction time 20 min. The linear range of this method is between 0 μg L^-1 and 12 μg L^-1 and the limit of detection is 0.011 μg L-1, the relative standard deviation （RSD） in five replicate determinations for 2 and 8 μg L-1 copper （ Ⅱ ） are 3.2% and 2.3%, respectively. Twenty ions do not interfere in the determination of copper （ Ⅱ ）. The method has been applied satisfactorily to the determination of copper （ Ⅱ ） in freshwater samples （tap water and Yellow River water from Lijin, Shandong, China） and seawater samples （from the South China Sea）, the recovery rates are 98.0%, 102.5% and 96.0%, respectively.  相似文献   

20.
A cruise was conducted from late August to early September 2004 with the intention of obtaining an interdisciplinary understanding of the Yangtze River Estuary including the biological, chemical and physical subjects. Water sample analysis indicated that total phytoplankton species richness was 137. Of them 81 were found in Bacillariophyta and 48 in Pyrrophyta, accounting for 59.1% and 35.0% respectively. The average cell abundance of surface water samples was 8.8×104 cells L-1, with the maximum, 102.9×104 cells L-1, encountered in the area (31.75°N, 122.33°E) and the minimum, 0.2×104 cells L-1, in (30.75°N, 122.17°E). The dominant species at most stations were Skeletonema costatum and Proboscia alata f. gracillima with the dominance of 0.35 and 0.27. Vertical distribution analysis indicated that obvious stratification of cell abundance and dominant species was found in the representative stations of 5, 18 and 33. Shannon-Wiener index and evenness of phytoplankton assemblage presented negative correlation with the cell abundance, with the optimum appearing in (30.75°N, 122.67°E). According to the PCA analysis of the environmental variables, elevated nutrients of nitrate, silicate and phosphate through river discharge were mainly responsible for the phytoplankton bloom in this area.  相似文献   

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