Direct Detection of Target Genes in Viable Bacteria and Extracellular DNA Using Loop-Mediated Isothermal Amplification Assay

When the loop-mediated isothermal amplification (LAMP) assay is used for detecting target genes, DNA extraction is unnecessary in many cases. Simple pretreatment (e.g. heating) is enough to obtain rather sensitive responses. Even test samples without any pretreatment can be used as template. This feature suggests that LAMP is superior to PCR in developing point-of-care test strategies. In this study, using Stx1 gene from E. coli as model, we verified that viable cells, dead cells and extracellular DNA could function as template in the LAMP assay. In the incubation at 63℃, viable bacteria in the LAMP reaction mixture lysed completely within 2 min, providing DNA template for nucleic acid amplification. The Stx1 gene in diluted culture medium, spiked tap water, spiked seawater and real seawater all could be detected, with or without the step of DNA extraction. We found that the complex substances in real sample (e.g. natural seawater) exhibited considerable inhibitory effect on the sensitivity of the LAMP assay. These outcomes are meaningful for building a point-of-care strategy by employing the LAMP assay for environmental monitoring, bio-resource surveys, food safety, etc. in particular those based on environmental DNA.     

基于模糊AHP的长寿湖生态系统健康评价

Ecosystem health assessment is a focus and hot spots field of ecological research, there is no unified evaluation indicators and evaluation methods. First, according to the area physical, human features of the Changshou lake and existed research, We established ecosystem health evaluation system which has included three secondary indexes ： the ecological characteristics indicators, the function indicators and the socio - economic indicators, and has 20 indicators. Second, we assess the Changshou lake ecosystem with the ecosystem health index which based on the fuzzy AHP. The conclusions are as follows： in 2006, the Changshou lake ecosystem health index was 0. 471, it is showed that the ecosystem is in sub health, the mainly reasons is its upper reaches of the Di- anjiang county, Liangping county long - term discharge of industrial sewage and pollution of fencing fish.     

饥饿胁迫对鲤肠道与肝脏蛋白酶和淀粉酶活性的影响

The aim of the present study was to determine the effect of starvation on digestive enzymes activity of the carp （Cyprinus carpio） at the water temperature 18 -20℃ in the cycle and flow water aquarium. The experiment was designed for four groups with three replication,which were 0 day（control） , 10 days, 20 days, 30days group. The results showed That there was a trend to drop first and keep stabilization for Cyprinus carpio body weight and Meat Content with the prolongatin of starvation, and that Effect of starvation stress on the the activity of protease in intestine and hepatopancreas of Cyprinus carpio was significant, with the prolongatin of starvation, there was a trend to increase then drop for the activity of protease in fore-gut, mid-gut hind-gut and hepatopancreas of Cyprinus carpio. And that the variatin for activityof amylase in fore-gut was significant butthat of the others was no significant.     

羊栖菜和裙带菜中抗凝血活性物质的初步筛选

Components with blood-anticoagulant activity were fractionated from marine algae Sargassumfusiforrne and Undaria pinnatifida and the activity of the components was investigated by using the method of bioassay. It was found that the 80% ethanol soluble fraction of Sargassumfusiforme exhibited no blood-anticoagulant activity, while the components obtained from the 80 % ethanol insoluble fraction (hot water extract) gave obvious bloodanticoagulant activity. A further study suggests that the principal component in the hot water extract from Sargassumfusiforrne with high blood-anticoagulant activity should be sulfated polysaccharides, in which the activity was positively correlated with the content of total sugar and fucose in sulfated polysaccharides. As for Undaria pinnatifida, the n-butanol extract fractionated from the 80% ethanol soluble fraction had blood anticoagulant activity, while the petroleum ether, ether, ethyl acetate, or water extract showed no bloodanticoagulant activity.     

坛紫菜自由丝状体对无机碳的利用

Free-living Porphyra haitanensis conchocelis was cultured under continual light,then it was treated with Van,DIDS and SITS,the inhibitors of inorganic carbon utilization,to study the mechanism of inorganic carbon utilization in the conchocelis.The results indicate that Van inhibits the utilization of inorganic carbon most,with a rate of 71.3%,and the rates of DIDS and SITS are relatively lower,42% and 35.5% respectively.The inhibition rate of Az is 25.3%,which indicates the external CA is not an important part of its inorganic carbon uptake.A complementary conclusion is that the main part of inorganic carbon absorption in P.haitanensis conchocelis is through active transport of HCO3^- and CO2.     

^60Co-γ射线对成体长牡蛎生长的影响及致死效应

Effects of ionizing irradiation of ^60Co-γ ray on mortality and growth of one year-old Pacific oysters ( Crassotrea gigas ) were studied. Irradiation was conducted at 4℃ and without sea water, and the survival, shell length, shell width, whole wet weight and condition index of irradiated oysters were measured. A biphasic dose response effect of 6^60Co-γ irradiation on Pacific oyster with high stimulatory response dose range to 100 Gy, and strong hormesis effects had been observed. Gamma ray induced mortality happened within 90 days after irradiation, and the relation between dosage ( D ) and mortality at 90 days could be described by the equation of M90 = 0.0041D^2- 0. 1816D (R^2= 0. 9958) with an LD50/90 of 135 Gy, indicating that the Pacific oyster has strong resistance to ^60Co-γ irradiation. Growth in shell length, shell width and whole wet weight of Pacific oyster were also enhanced by 60 Gy of ^60Co-γ ray. The condition index was also enhanced by ^60Co-γ irradiation in the dosage range from 40 to 100 Gy, with the maximum stimulatory response of 2.5 fold of control value at the 40 Gy dosage, suggesting that the accelerating effects of γ ray on growth of the Pacific oyster led to increase in dry meat. Results of this study showed that ionizing irradiation might be useful in the improvement of production traits in shellfish.     

彭泽鲫的分子遗传分析及其与方正银鲫A系的比较

Genetic homogeneity between Pengze crucian carp and strain A of silver crucian carp was studied by using transferrin,isozyme and RAPD markers.The studied individuals of Pengze crucian carp showed transferring patterns were the same of silver crucian carp A strain while distinct from those of other crucian carp populations.As far as isozyme is concerned,the MDH,LDH and EST are all of the same with only slight differences in SOD between them.The RPAD patterns clearly indicated high homogeneity among 16 individuals (6 sampled from individuals of two years old and the others aged one) from crucian carp of Pengze and 5 individuals from strain A of silver crucain carp.Nearly indentical banding patterns were observed among all individuals.Average genetic distance within all the individuals is only 0.011,suggesting crucian carp of Pengze might possess indentical genetic background with strain A of silver crucian carp.     

蚤状溞对海水盐度的耐受力研究

The reproduction and survival of Daphnia pulex Straus under salinities of 2,3,4,6,8,10 and 15℃,20℃,25℃ has been stu died.The results show that the alternate effect of salinity and temperature is o utstanding.The developmental rate of D.pulex goes up with the increa se of temperature under a certain salinity,and the total life span reduces with the increase of salinity under a certain temperature. The optimum salinity-tempe rature combination level is salinity 2 and temp.20℃.The upper salinity limit of reproduction is 4.After short-term training between 15～25 ℃and at 25℃,the up per salinity limit of reproduction and survival is 6.     

ABSTRACTS AND KEY WORDS

Added bagasse and Bacillus sp. to Litopenaeus vannamei intensive culture tank, the treatment groups were treatment A（added Bacillus sp.）, treatment B（added Bacillus sp. with crushing bagasse） and treatment C（added Bacillus sp. with crushing-steaming bagasse） respectively. To estimate the effect of addition of bagasse with Bacillus sp. on the culture environment and shrimp growth, the level of total ammonia nitrogen（TAN）, nitrite nitrogen and nitrate nitrogen, total amount of bacteria in the water and shrimp growth were determined. The result suggested that the TAN concentration in treatment B and C were significantly lower than that in treatment A during the early stage of the culture（P〈0.05）. The addition of bagasse with Bacillus sp. was contribute to the formation of bio-floccules. The concentration of bio-floccules in treatment B and Cwere 6.3-20 ml/L and 8.3-30 ml/L respectively, which were significantly higher than that in treatment A（2.7-8.3 ml/L） during the culture（P〈0.05）.The average weight of shrimp in treatment B and C were 8.56±0.21g and 8.84±0.26g respectively, which were significantly bigger than that in treatment A（7.66±0.40g） when harvest（P〈0.05）.     

线纹尖塘鳢的形态生物学与核型

This paper reports the morphological character and karyotype of Oxyeleotris lineolatus. Oxyeleotris lineolatus is native in Australia and call ed sleepy cod. It belongs to Oxyeleotris, Eleotridae, Gobioidei, Perciformes in taxonomy. Recently, it was introduced to China and local people were not familiar with it. So we carried out this study. 30 individuals have been observed and some data were recorded. It has a large mouth that is in front and up. The mandible stands out and is longer than the up jaw. There are many rows of thin teeth in up and down jaws. The pelvie fins are located in chest and pectoral fins are large and fanlike. There are two dorsal fins. The tail fin is circular. Gill rakers are sparse and the number of gill rakers is 8-12+3-4. The gas bladder belongs to physoclistaus and its stomach is strong and I-like. The intestine is thick and short and no pyloric caecas. The length of the digestive path is 48.1％-80.3% of the length of body. Its liver has two lobes and the liver weight is 4.1%-7.2% of the body weight. The digestive organs characters are same as the trait of flesheater fish. Its scale belongs to ctenoid scale and its body surface shows several long lines. There is not lateral line in the body. The number of vertebra is 26-27 and it has 10-11 pairs rib. The number of diploid chromosome is 2n=46 and the karyotype formula is 2sm+8st+36t，NF=48. The relative length of chromosome is from 1.37% to 3.48% and it is continuity. No strange size chromosomes relation to sex was observed. The karyotype of Oxyeleotris lineolatus is similar to that of Oxyeletris marmoratus Bleeker from South East Asia and both of them belong to Oxyeleotri. It testifies the correctness of traditional classification on cytology.     

复合有益菌剂对工厂化大菱鲆育苗水净化效果研究

On the basis of purifying effect of single strain probiotic bacteria on water of intensive turbot breeding, the purifying effect of multistrain bacteria product was studied. The results of experiments showed that the free multistrain mixed bacteria had better purifying effect on turbot breeding water than that of any singlestrain bacteria. this phenomenon can be explained with the principle of “ biopump”. The immobilized multistrain probiotics product, biofilm, also showed excellent purifying effect on wate r of turbot breeding. The removal rates of COD and ammonia in 5 days were up to 73.1% and 80.0%, respectively. The concentration of nitrite kept low, which indicated most ammonia had been transformed into nitrate and accumulation of harmful intermediate productnitrite was decreased. This paper supplied theoretical and technical foundation for saving sea water through biopurification of wastewater from marine fish culture.     

甲胺磷、辛硫磷对坛紫菜叶状体的生理效应

In this paper, the effects of methmidophos and phoxim with different concentrations and schedule on soluble protein content and chlorophyl a (Chla) content in Porphyra haintanensis were studied under experimental and ecological conditions. The results showed as follows: (1) there were some time-effect and dose-effect relationships between the pollutants and Chla contents. The Chla content of most of groups decreased with the increasing of dose and prolonging of the exposure time. In the same concentration, the toxicities of phoxim to Chla content was stronger than that of methmidophos. (2) All concentration groups in this study didn‘t show the significant time-effect and dose-effect relationships between pollutants and the soluble protein. And there was no significant difference of the soluble protein content among various groups.     

芝芪菌质对罗氏沼虾生长和免疫及中肌苷酸含量的影响

The purpose of this paper is to evaluate the effect of Zhiqi Fungal Substance on their performance, immunity , and meat quality in Macrobrachium rosenbergii. Macrobrachium rosenbergii were allotted into four groups randomly. The control group were fed with basal diet, the others were the treated groups fed with basal diet supplemented with 0.25% ,0.5% ,1% Zhiqi Fungal Substance for 35 days, respectively. The results showed Zhiqi Fungal Substance can imporve the production of shrimpand and the survival rate. Zhiqi Fungal Substance increased the LSZ and SOD level（P 〈 0. 05） compared to control. Addition of 0.5% and 1% Zhiqi Fungal Substance increased the AKP and the ACP level（P 〈 0. 05）. It is indicated that dietary Zhiqi Fungal Substance can improve the flavor of cultured shrimp.     

细角螺的繁殖生态条件及繁殖习性

Hemifusus ternatanus(Gmelin), a gastropoda living in the deep water areas of undertide,as well as a delicious seafood, was distributed mainly in Chinese southeast seas and Japanese seas near the coast. In this experiment Hemifusus ternatanus' breeding ecological conditions and its propagation habit were studied in order to provide an experimental foundation for the artificial breeding. The brood stocks of test animals collected from the waters in Taiwan Strait, and then were examinated their growing temperature， salinity, feeding and propagation habit in the laboratory. The re sults showed that the growing temperature for Hemifusus ternatanus ranges from 16 ℃ to 32 ℃, with an optimum temperature between 20 ℃ to 28 ℃ and between 23 ℃ and 28 ℃ for breeding. The optimum growth salinity was 18.3-32.3 though it much adapts to salinity from 13 to 35. They prefer to feed on bivalves particularly those with thin shells and byssusless. Hemifusus ternatanus is dioecious and fertilization finishes inside the body. It was called as egg vesicle procreation that the whole stages of embryo growth were developed within egg vesicle. Larva forms as soon as it leaves egg vesicle, which is called direct occurrence type. The larva became the juvenile after metamorphosis during 20-25 days development. It was first to obtained 233 juveniles with shell height 32-45 mm by an artificial breeding method.     

象山港浮游动物生物量和丰度的季节变动

On the basis of the data of zooplankton collected from 20 stations in Xiangshan Bay in January, April, July and October, 2000, the abundance and biomass of zooplankton and the relations to mariculture environment are analyzed in this paper. The results show that there were significant seasonal variations in zooplankton biomass and abundance in the surveyed area. The biomass peaked in July, followed by April and October, and the lowest biomass appeared in January. The highest abundance was observed in April, followed by July, October and January. There were similar horizontal distribution patterns for the biomass and abundance of zooplankton. They both decreased from bay head to bay mouth in January and April, but increased from bay head to bay mouth during October. Biomass and abundance were distributed evenly in the surveyed area in July. The zooplankton biomass and abundance in cage culture area were apparently lower than those in non-culture area indicating that cage culture has negative effects on zooplankton in surrounding waters.     

美洲黑石斑鱼营养成分分析与营养价值评价

In this experiment, the contents of the main nutrients such as protein, fat, moisture, ash, calcium and phosphorus were analysed, and the contents of the trace elements, amino acids and fatty acids in its muscle were determined for Centropristis striata. Moreover, its nutritional value was evaluated and compared with other fishes,livestocks and poultries. The results showed that the content of dry matter and protein are higher in its muscle. Then, all of 17 common amino acids（AA） contents in muscle was 17.51% in the fresh sample, and 7 of them are human essential amino acids（EAA）41.58% in the total amino acids（TAA）. The ratio of essential amino acids to nonessential amino acids（EAA/NEAA） was 84.46% ,and the essential amino acids index（EAAI） was 57.71. According to AAS and CS,which basically accorded with the issued standard value by FAO and WHO. The content of 5 delicious amino acids was 44.37% in the TAA, and the ratio of branched chain amino acids to aromatic amino acids was 2.83. The content of polyunsaturated fatty acids was 22.3% rich in its muscle also, in particular EPA and DHA. In conclusion, Centropristis striata is a species of delicious and high nutritional value,which well deserves exploitation and utilization. At the same time, this experiment was preparing for the next study to provide reference data for artificial feed and the expansion of aquaculture.     

Modulation of calcium uptake in cadmium-pretreated tilapia (Oreochromis mossambicus) larvae

Tilapia larvae were exposed to 0 (control), 50 (50-Cd) or 100 (100-Cd) μg l^-1 cadmium for 4 days and then transferred to cadmium-free fresh water for 3 days of detoxification. Total length and weight, calcium influx and total body calcium and cadmium content were examined at various times during detoxification. All the groups grew normally with regards to total length and body weight. Within the first 12h of detoxification the 50- and 100-Cd exposed groups released cadmium at the similar rate of about 24 ng mg^-1 h^-1 (or 140 ng larva^-1 h^-1). Later, however, this rate declined to only 4–16% of the initial level. Calcium influx in the control group showed a 10–26% increase during the detoxification period. Calcium influx in the 50-Cd group increased by about 280% and reached it peak at 12h. Calcium influx in the 100-Cd group increased by 440% and did not peak until 24h after transfer. After peaking, the influxes in both 50- and 100-Cd groups declined to the level of control at the end of the experiment. Calcium contents in 50- and 100-Cd groups increased more rapidly than that in control group within first 24h of the detoxification period. However the rate of increase in calcium content in three groups was the same after 24h. The changes in calcium influx appeared to be correlated with those in calcium content, and these suggested that tilapia larvae regulate the mechanism of calcium balance to compensate for the reduced calcium level in the body. This revised version was published online in July 2006 with corrections to the Cover Date.     

江黄颡鱼卵细胞膜的结构特征

Using conventional histochemical methods and scanning electron microscope, the egg surface of mature oocyte of Pelteobagrus vachelli was observed. The micropyle is funnel-like and consists of micropylar vestibule and micropylar canal. The opening of micropylar vestibule is about 11.35μm in diameter while entrance of the micropyle to the oocyte is only about 2.6 μm. There are plenty of micropores on the surface near the micropyle. Micropyle might act as an apparatus leading spermatozoa to penetrating an oocyte. Regular cord-like structures between basal membrane (the outermost layer of egg surface) and plasmic membrane (the inner layer of egg surface) are found. These cord-like structures, each about 16.75 to 18.50μm in length, 5μm in diameter, comprised small balls whose diameters vary from 2.18 to 2.5μm and are arranged cornpactly under the basal membrane. These kinds of structures are zona radiata and act as special eggshell. After activation of the oocytes, the cord-like structures would partially transform into mucoprotein. To our best knowledge, this paper is the fast report on stereo view of the zona radiata of teleost oocyte.     

半滑舌鳎染色体核型分析

The tonguefish Cynoglossus semilaevis (Giinther) is a rare fish species in Chinese offing, inhabiting in the warm water bottom. The metaphase chromosome preparation of the fries has been got from their fins by hot air drying methods, while the metaphase chromosomes of one year old young fish which has physiologically sex differentiation has teen got from their renal tissues by the method of PHA and colchicine injection. The karyotypes were examined. The result shows that there are 42 acrocentric chromosomes in diploid and their karyotype formula is 2n = 42t, and there existed heterotypic sex chromosome which belongs to ZW/ZZ type. The sex ratio in artificial bred stock is nearly 1 : 1.     

斑点叉尾鮰病毒对几种淡水鱼类细胞系感染性的初步研究

To study the susceptibility of multiple fresh water fish cell lines to channel catfish virus （CCV） and to evaluate and assess potentially pernicious impact of CCV on several rare and important economic fish species in China. Five cell lines established from several fish species including grass carp fins （GCF）, epithelioma papulosum cyprini （ EPC）, white sturgeon spleen （ WSS - 2 ）, chinook salmon embryo （ CHSE - 214 ） and parental control channel catfish ovary （CCO） were tested and compared for their sensitivity to CCV infection. After virns infection, test cells were characterized by cell morphology, cytopathic effect （CPE） appearance time, and infectious virus titer. Our results indicated that all these cell lines were sensitive to CCV, but at varied levels. Comparative viral challenge assays revealed that, among these five fish cell lines, GCF exhibited to be the most sensitive one to CCV infection, and infectious viral particles produced in this cell line is significantly more than that generated from parental CCO cells. EPC cells were also highly susceptible to CCV infection with a similar level of viral production as compared to CCO. Experimental data showed that all the test five cell lines were susceptible to CCV and present study suggests that CCV can be a potential pathogen to infect gYass carp, Cyprinus carpio and other fresh water fishes.