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1.
1 INTRODUCTIONThepenaeidshrimpcultureindustriesintheworlddevelopedfromtheirexperimentalbeginningslessthanthirtyyearsagointoamajoraquaculturein dustrytodaythatprovideshundredsofthousandsofjobs,billionsofU .S.dollarsinrevenue,andaug mentstheglobalfoodsupplywithahighvaluecrop(LighterandRedmam ,1 998) .Upto 1 995,farmedshrimpatvolumeof71 2 0 0 0MT ,almostallconsistingofPenaeidspecies,accountedfor 2 7%ofworldshrimpproduction.Inthatyear,asoneofthemostimportantculturedshrimp,theproductionofP…  相似文献   

2.
Effects of hypoxia on the dopamine concentration and the immune response of White Shrimp Litopenaeus vannamei were studied. The results showed that hypoxia had significant effects on the concentration of dopamine (DA) in the haemolymph, haemocyte count, phenoloxidase activity, phagocytic activity of haemocytes and bacteriolytic and antibacterial activity in the haemolymph (P<0.05). The concentration of the dopamine in haemolymph reached its maximum in the 3.0 and 1.5 mg L−1 DO groups at 12 h and 6 h, and then returned to normal after 24 h and 12 h, respectively. All immune parameters decreased with the reduction of dissolved oxygen. Total haemocyte count (THC), the hyaline cells and semi-granular cells in the 3.0 mg L−1 DO group became stable after 12 h, while granular cells did so after 24 h. The THC and different haemocyte count (DHC) in the 1.5 mg L−1 DO group became stable after 24 h. Phenoloxidase activity and bacteriolytic activity in the 3.0 and 1.5 mg L−1 DO groups reached their stable levels after 24 h and 12 h respectively, while phagocytic activity and antibacterial activity became stable after 24 and 12, and 36 and 24 h, respectively. It was also indicated that the changes of dopamine concentrations in haemolymph, haemocyte count and phenoloxidase activity were obviously related to the exposure time under hypoxic conditions.  相似文献   

3.
Inorganic lead (Pb) is one of the most common environmental pollutants. Much evidence indicates that Pb exposure could directly affect fish growth and development. In this study, we investigated the cytotoxic effects of Pb on cytoskeletal protein stability at both protein and mRNA level in crucian carp Carassius auratus. Pb(NO3)2 treatment in concentration of 100 μmol/L resulted in decreased expression of both α- and β-tubulin but γ-tubulin as assayed with SDS-PAGE, Western Blot, and ELISA. In vivo and in vitro analyses on protein expression of tubulins are consistent. The effect of Pb on mRNA expression varied among different tissues. Our results suggest that cytotoxicity of Pb at protein translation level is stronger than at mRNA expression level.  相似文献   

4.
In vitro acute cytotoxicity of neonicotinoid insecticide imidacloprid (IMI) to the gill cell line of flounder (FG) that collected in the gill of Paralichthys olivaceus, was examined by 3 widely used endpoint bioassays: NR (neutral red), MTT (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) and TCP (total cell protein). The result shows that the IMI increased at concentrations ≥0.5 μg/ml. The IC50 value of NR, MTT, and TCP was 41.86, 38.46, and 39.08 μg/ml, respectively. The ultrastructural observation revealed that the mitochondria of the cells exposed to 60 μg/ml IMI for 48 h were severely damaged, swollen or disrupted, while their nuclei and rough endoplasmic reticulum (RER) remained normal. This would suggest that the mitochondria are probably the primary target of IMI.  相似文献   

5.
Abalone Haliotis diversicolor supertexta is an important economic mollusk. The settlement and metamorphosis are two critical stages during its development period, which has direct influence on abalone survival and production. The influence of reactive oxygen species (hydrogen peroxide) on abalone embryo and juvenile development were examined in this study. Larvae of Haliotis diversicolor supertexta were induced to settlement and metamorphose by exposure to seawater supplemented with hydrogen peroxide. They had the best performance at 800 μmol/L. The concentration of 1 000 μmol/L or higher was toxic to the larvae, as the larvae could settle down only at benthic diatom plates without complete metamorphosis. In addition, H2O2 adding time was critical to the larval performance. 24h after two-day post-fertilization was proved to be the optimal adding time. In this paper, two action mechanisms of hydrogen peroxide are discussed: (1) hydrogen peroxide has direct toxicity to ciliated cells, thus cause apoptosis; (2) hydrogen peroxide, as a product from catecholamines' autoxidation process in vivo, can reverse this process to produce neuro-transmitters to induce abalone metamorphosis.  相似文献   

6.
To investigate the antitumor effect of bromophenol derivatives in vitro and Leathesia nana extract in vivo, six bromophenol derivatives 6-(2,3-dibromo-4,5-dihydroxybenzyl)-2,3-dibromo-4,5-dihydroxy benzyl methyl ether (1), (+)-3-(2,3-dibromo-4,5-dihydroxyphenyl)-4-bromo-5,6-dihydroxy-1,3-dihydroisobenzofuran (2), 3-bromo-4-(2,3-dibromo-4,5-dihydroxybenzyl)-5-methoxymethyl-pyrocatechol (3), 2,2′,3,3′-tetrabromo-4,4′,5,5′-tetrahydroxy-diphenylmethane (4), bis(2,3-dibromo-4,5-dihydroxybenzyl) ether (5), 2,2′,3-tribromo-3′,4,4′,5-tetrahydroxy-6′-ethyloxymethyldiphenylmethane (6) were isolated from brown alga Leathesia nana, and their cytotoxicity were tested by MTT assays in human cancer cell lines A549, BGC-823, MCF-7, B16-BL6, HT-1080, A2780, Bel7402 and HCT-8. Their inhibitory activity against protein tyrosine kinase (PTK) with over-expression of c-kit was analyzed also by ELISA. The antitumor activity of ethanolic extraction of Leathesia nana (EELN) was evaluated on S180-bearing mice. All compounds showed very potent cytotoxicity against all of the eight cancer cell lines with IC50 below 10 μg/mL. In PTK inhibition study, all bromophenol derivatives showed moderate inhibitory activity and compounds 2, 5 and 6 showed significant bioactivity with the inhibition ratio of 77.5%, 80.1% and 71.4%, respectively. Pharmacological studies reveal that EELN could inhibit the growth of Sarcoma 180 tumor and increase the indices of thymus and spleen to improve the immune system remarkably in vivo. Results indicated that the bromophenol derivatives and EELN can be used as potent antitumor agents for PTK over-expression of c-kit and considered in a new therapeutic strategy for treatment of cancer. Supported by the National High Technology Research and Development Program of China (863 Program, No. 2007AA09Z410) and Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-209)  相似文献   

7.
A laboratory experiment was conducted to assess the bioaccumulation of Pb2+ and its effects on growth, morphology and pigment contents of Spirulina (Arthrospira) platensis. The specimen cultured in Zarrouk liquid medium was treated with various initial metal concentrations (0, 5, 10, 30, 50 and 100 μg mL−1). The growth of S. platensis was adversely affected by Pb2+ at high concentrations (30, 50 and 100 μg mL−1). However, at low concentrations (5 μg mL−1), Pb2+ could stimulate its growth slightly. The pigment contents (chlorophyll α and β carotene) were decreased in a dose-dependent manner. The highest reductions (67% and 53% respectively in chlorophyll α and β carotene) were observed in 100 μg mL−1 treatment group. The LC50 (96 h) of Pb2+ was measured as 75.34 μg mL−1. Apart from a few cases of filament breakages at elevated concentrations (50 and 100 μg mL−1), morphological abnormalities are not specific. Metal bioaccumulation increased with Pb2+ concentrations, but decreased with exposure time. The maximum accumulated amount was 188 mg g−1 dry weight. The bioconcentration factor (BCF) reached to a peak at day 2, followed by a gradual reduction for all the exposure concentrations. S. platensis is able to tolerate considerably high Pb2+ concentrations. Consequently it can be used as a potential species to remove heavy metal from contaminated waters.  相似文献   

8.
To investigate the effect of polypeptide fromChlamys farreri (PCF) on NHDFin vitro, we modeled oxidative damage on normal human dermal fibroblasts (NHDF) exposed to ultraviolet B (UVB). In this study, 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) were tested to measure cell viability. Enzymes including superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), catalase (CAT) and xanthine oxidase (XOD) were determined biochemically. Total antioxidative capacity (T-AOC) and anti-superoxide anion capacity (A-SAC) were also determined. Ultrastructure of fibroblasts was observed under transmission electron microscope. The results showed that: UVB (1.176×10−4 J/cm2) suppressed the growth of fibroblasts and the introduction of PCF (0.25%–1%) before UVB reduced the suppression in a concentration-dependent manner. PCF could enhance the activities of SOD, GSH-PX and T-AOC as well as A-SAC. Also PCF could inhibit XOD activity, while it did not affect CAT activity. Ultrastructure of fibroblasts were damaged after UVB irradiation, concentration-dependent PCF reduced the destructive effect of UVB on cells. These results indicated that PCF can protect human dermal fibroblasts from being harmed by UVB irradiation via its antioxidant proerty. This work was supported by the National Natural Science Foundation of China (No. 39970638) and the Science and Technology Bureau of Qingdao (No. 2001-28-50).  相似文献   

9.
The pathological changes of hemocytes in the haemolymph and hepatopancreas were examined in experimentally and naturally WSSV (white spot syndrome virus) infected Fenneropenaeus chinensis. The results showed that the pathological manifestations of hemocytes were similar among moribund shrimps infected via injection, feeding and by nature. Firstly, the total hemocyte counts (THCs) in WSSV-infected shrimp were significantly lower than those in healthy shrimp. Secondly, necrotic, broken and disintegrated cells were often observed, and a typical hematolysis was present in the haemolymph smear of WSSV-infected shrimp. Thirdly, necrosis and typical apoptosis of hemocytes were detected with TEM in the peripheral haemolymph of WSSV-infected shrimp. Hyalinocytes and semi-granulocytes with masses of WSSVs in their nuclei often appeared, whereas no granular hemocytes with WSSV were found in the hepatopancreas of moribund infected shrimps. All our results supported that hemocytes were the main target cells of WSSV, and hyalinocytes and semigranular hemocytes seemed to be more favorable for WSSV infection in F. chinensis.  相似文献   

10.
The effects of 60-day starvation on survival rate. condition index (CI) , changes ofnutrient composition of different tissues, respiration and excretion of scallop ChlartnCs farreri were studiedin laboratory from Oct. 17 to Dec. 15 ,1997. Two groups (control and starvation with 200 individualseach) were cultured in two 2 m3 tanks, with 31 to 32 salinity water at 1 7 “C . Starvation effects were mea-sured alter 1 0, 20, 40 and 60 days. There was no mass mortality of scallops cf the two tanks and survivalrates of the control and starvation groups were 93 .5 % and 92.0 %, respectively. Starvation had strongeffect on the meat condition of the scallops, especially after 10 days; when relative lipid percentagedropped sharply while relative protein percentage increased. The impact of starvation on the oxygen consumption mtc (OCR) and the ammonia-N cxcretion mtc (AER) was obvious.  相似文献   

11.
Twenty-four compounds including eight steroids (1–8), nine triterpenoids (9–16, 24), three flavonoids (20–22), and four benzenecarboxylic derivatives (17–19, 23) were isolated and identified from stems and twigs of medicinal mangrove plant Sonneratia caseolaris. The structures of the isolated compounds were determined by extensive analysis of their spectroscopic data. Among these metabolites, compounds 1, 4–20 and 22–24 were isolated and identified for the first time from S. caseolaris. In the in vitro cytotoxic assay against SMMC-7721 human hepatoma cells, compound 21 (3′,4′,5,7-tetrahydroxyflavone) exhibited significant activity with IC50 2.8 μg/mL, while oleanolic acid (14), 3,3′-di-O-methyl ether ellagic acid (18), and 3,3′,4-O-tri-O-methyl ether ellagic acid (19) showed weak activity. None of these compounds displayed significant antibacterial activites. Supported by the National Natural Science Foundation of China (No. 30770234); Knowledge Innovation Program of Chinese Academy of Sciences (KZCX2-YW-211-04); Department of Science and Technology of Shandong Province (No.2006GG2205023)  相似文献   

12.
1INTRODUCTIONTheWestLake ( 30°1 5′N ,1 2 0°1 6′E)isasmallshallowlakeinthewesternpartofHangzhouCityinthesoutheasterncoastalareaofChina.Thelakeissur roundedonthreesidesbyhills ;andisfamousforitspicturesquesceneryandinterfusionofhillsandwaterbodies.Thesurfaceareaisabout 5 .66km2 andmeandepthis 1 .8m .Beforethe 1 95 0s ,thelakewaterwascleanandmacrophytesgrewveryluxuriantlyinthelit toralareasofthelake .In 1 95 2 ,WestLakewasdredgedand 70 0× 1 0 4m3 mudwasremovedfromthebottomofthelake …  相似文献   

13.
The characteristics of a bacterium strain M3, isolated from cultured flounderParalichthys olivaceus with remarkable external sign of skin ulcer during an epizootic outbreak, indicated that the bacterium belonged to the speciesVibrio anguillarum. Challenge by I.M. (intramuscular injection), bath, and oral administration with M3 showed that it was highly pathogenic forParalichthys olivacues. The LD50 dose was 5.144×103 CFU/ per fish infection by I.M. injection. Recovered inoculated bacteria from the surviving fish revealed that the asymptomatic carriers could be a latent contagious source. Study of the effect of bacterial culture CFS (cell-free-supernatant) showed that the exotoxins produced by M3 play an important role in its pathogenicity for flounder. The resistance of M3 to 36 out of 41 antibiotics indicated that the bacterial disease outbreak was mainly attributable to the frequent and excessive use of antimicrobial agents; and that vaccination would be an effective precaution against bacterial disease. Contribution No. 4107 from Institute of Oceanology, Chinese Academy of Science. Contribution No. 270 from Experimental marine Biology Laboratory, CAS. Funded by projects under the Major State Basic Research Development Program, Grant G1999012003.  相似文献   

14.
Distribution, variation and impact factors of biomass of bacterioplankton from April to May 1999 in Bohai Sea were studied in DAPI method with epifluorescence microscopy. The biomass in surface waters showed a small day-night variation, varying from 0.13 to 2.51μg/dm^3 with an average of 0.84μg/dm^3. The biomass in bottom waters showed, however, a large variation, changing from 0.15 to 4.18μg/dm^3 with an average of 1.36μg/dm^3. The peak values occurred at 5 and 11 a.m. The bottom water biomass showed a significant correlation with particulate organic carbon (r=0.639, P〈0.05). Heterotrophic bacterioplankton biomass was high in nearshore waters and low in offshore areas with a high biomass zone around Huanghe (Yellow) River mouth, showing the same distribution of nutrients. In vertical distribution, heterotrophic bacteria biomass in bottom waters was higher than that in surface water.  相似文献   

15.
Effects of reduced salinity on the oxygen consumption rate (OCR) and the ammonia-N excretion rate (AER) of scallopChlamys farreri (3.2–5.9 cm in shell height, 0.147–1.635 g in soft tissue dry weight) were studied in laboratory from March 21, 1997 to April 16, 1997. Under the controlled conditions of reduced salinity from 31.5 to 15.0 and ambient temperature 17°C and 23°C, the concentrations of dissolved oxygen and ammonia-N were determined by the Winkle method and the hypobromite method, respectively. Results showed that with controlled reduced salinity, the mean values of the OCR were 2.17 mg/(g.h) at 17°C, and 2.86 mg/(g.h) at 23°C and that the mean values of the AER were 178.0 μg/(g.h) at 17°C and 147.0 μg/(g.h) at 23°C. The OCR and the AER decreased with reducing salinity from 31.5 to 15.0 both at 17°C and 23°C. The effects of reduced salinity on the OCR and the AER of scallopC. farreri could be represented by the allometric equation and the exponential equation, respectively. Contribution No. 3295 from the Institute of Oceanology, Chinese Academy of Sciences. Project supported by the National Ministry of Science and Technology of China and by the Chinese Academy of Sciences, Grant No. 96-922-02-04 and KZ951-A1-102-02.  相似文献   

16.
Flagella, the basic locomotive organ in algae, as well as bacteria and some cells of animals or high plants, would be damaged in the well stirred mass culture due to the strong forces caused by the fast mixing impellers. The dynamic regeneration of the flagella in deflagellatedDunaliella salina was studied microscopically by using a bench-top flat-bottom photobioreactor. The results showed that 90 minutes was necessary for the repair of flagella, after which half of the cells became motile as their flagella generated within 120 minutes and nearly all of the cells could swim freely within 180 minutes. Contribution No. 3503 from the Institute of Oceanology, Chinese Academy of Sciences.  相似文献   

17.
Sulfotransferase (ST) is the first enzyme discovered in association with paralytic shellfish poisoning (PSP) toxin biosynthesis in toxic dinoflagellates. This study investigates the ST activity in crude enzyme extraction of a toxic dinoflagellate species, Alexandrium tamarense CI01. The results show that crude enzyme can transfer a sulfate group from 3’-phosphoadenosine 5’-phosphosulfate (PAPS) to N-21 in the carbamoyl group of gonyautoxin 2/3 (GTX2/3) to produce C1/C2, but is inactive toward STX to produce GTX5. The crude enzyme is optimally active at pH 6.0 and 15°C. The activity is enhanced by Co2 , Mg2 , Mn2 and Ca2 individually, but is inhibited by Cu2 . Moreover, the activity shows no difference when various sulfur compounds are used as sulfate donors. These results demonstrate that the ST specific to GTX2/3 is present in the cells of A. tamarense CI01 and is involved in PSP toxin biosynthesis. In addition, the ST from different dinoflagellates is species-specific, which explains well the various biosynthesis pathways of the PSP toxins in toxic dinoflagellates.  相似文献   

18.
The hybrid between olive flounder Paralichthys olivaceus and stone flounder Kareius bicoloratus was produced by artificial insemination of olive flounder eggs with stone flounder sperm. Sinistral and dextral are two types of hybrid progeny after metamorphosis. Karyotypes of both hybrid flounders are the same as those of the two parental species. Of the 22 loci examined from 12 allozymes, 12 confirmed hybridization of the paternal and maternal loci in hybrids and no difference was found in allozyme patterns of sinistral and dextral hybrid fishes. RAPD patterns of these specimens were also studied with 38 primers selected from 104 tested. Among them, the PCR products of 30 primers showed hybridization of the paternal and maternal bands. Genetic variation between hybrids and their parental stocks was analyzed by RAPD using 10 of the above 38 primers. The average heterozygosity and genetic distance were calculated. The results suggested that the filial generation could inherit a little more genetic materials from paternal fish than that from maternal fish. Supported by National Natural Science Foundation of China (No. 30571445), National High-Technology Research and Development Program (863 Program, No. 2006AA10A404), and Project from the Ministry of Science and Technology of China (No. 2006DKA30470-017)  相似文献   

19.
Fe, Chlorophyll (Chl) and total nitrogen (TN) content in tissues were measured in Fe-deficient cultures ofUlva. pertusa over a period of 60 days. Photosynthetic carbon fixation rates were studied at the start of and 30 days after Fe-deficiency culture, when the effects of Fe-deficiency on the ultrastructure were also analyzed. The iron content in tissue decreased exponentially during Fe-deficiency (from 726.7 to 31.6 μg/gdw) and simultaneously Chl and TN content declined to 4.35% and 59.9% of their original levels respectively. Maximum carbon fixation rate (50–250 μmol/m2 s) under Fe-deficiency decreased significantly compared with the control (p<0.01) and was 13.6 to 0.365 μg C/cm2 h. Photosynthesis in Fe-deficient cells became light-saturated at lower irradiance than that in control. Ultrastructural observations of Fe-deficient cells showed reductions in chloroplast number, some degeneration of lamellar organization, an increase in vacuolar area, a decrease in mitochondrial matrix density, and variation in accumulation body number and morphology. During Fe-deficiency, the algae growth rate continued to decline and after 6 weeks of iron deficiency, no further growth was detectable. These suggested that the lower growth rate ofUlva. pertusa under Fe-deficiency could be due mainly to nitrogen utilization and inhibition of photosynthesis. This project No. 39725023 supported by NSFC for Talented Youths and the Project under the Major State Basic Research of China (Grant No. G1999012011).  相似文献   

20.
This Mar. 1993 to Aug. 1994 study on suspended conchocelis ofPorphyra haitanensis showed that there were three patterns for development of vegetative filaments: filaments to filaments by “budding”; filaments to sporangial branchlets by “budding”, or cell swelling. There were also three patterms for sporangial branchlet development: vegetatively propagating, changing into conchospores, or dying. Each developmental stage had one or more different developmental directions between vegetative filaments and sporangial branchlets. Developments from conchosporangial branchlets to conchospores were sequential and irreversible. Although sporangial branchlets formed at 29°C could give rise to filaments, they could not propagate as healthily under the same conditions as those formed at 25°C did. Probably the crucial period of plant cell differentiation is in the late stage of sporangial branchlets. In line with the developmental directions of different stages, the authors regulated the development of conchocelis to get ideal different developmental stages materials to obtain very developmentally homogeneous stages, including filaments and sporangial branchlets. Contribution No 3283 from the Institute of Oceanology, Chinese Academy of Sciences. Study supported by the Climbing Project B PD-B6-4-2 of the State Science and Technology Commission of China.  相似文献   

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