There is limited information on whether parasites act as vectors to transmit bacteria in fish. In... more There is limited information on whether parasites act as vectors to transmit bacteria in fish. In this study, we used parasite Ichthyophthirius multifiliis and fluorescent bacterium Edwardsiella ictaluri as a model to study the interaction between parasite, bacterium and fish. The theronts after exposure to E. ictaluri showed significantly higher fluorescing bacteria (23-39 %) than control theronts (~6 %). Theronts exposed to E. ictaluri at 4 × 107 CFU mL-1 showed a higher percentage (~60 %) of fluorescent theronts compared to those (42 %) exposed to 4 × 103 CFU mL-1 at 4 h. All tomonts (100 %) carried the bacterium after exposure to E. ictaluri. E. ictaluri survived and replicated during tomont division. Confocal microscopy demonstrated E. ictaluri was associated with the tomont surface. Among theronts released from tomonts exposed to E. ictaluri, 31 – 66 % was observed with attached E. ictaluri. Sixty percent of fish exposed to theronts treated with 5×107 E. ictaluri mL-1 were pos...
… . Annu. Conf. Southeast. Assoc. Fish and …, 1995
Abstract: Human chorionic gonadotropin (HCG) is often used to induce spawning offish. However, th... more Abstract: Human chorionic gonadotropin (HCG) is often used to induce spawning offish. However, the US Food and Drug Administration has not approved HCG for use in fish because they claim additional efficacy data are required. Efficacy of HCG for spawning ...
The influence of cooking (frying, baking, and smoking) on dieldrin and 1,1-dichloro-2,2-bis[4-chl... more The influence of cooking (frying, baking, and smoking) on dieldrin and 1,1-dichloro-2,2-bis[4-chlorophenyl]ethylene (DDE) residues in treated channel catfish (Ictalarus punctatus) was determined. Dieldrin and DDE were significantly reduced (P < 0.05) during cooking of catfish by 50 to 65% (dry basis) and 50 to 80%, respectively. Smoking resulted in maximum reduction (82%) of DDE residues, while baking resulted in the least reductions for both dieldrin (50%) and DDE (50%) when compared to the other preparation methods.
One monoclonal antibody (mAb 3F6) against coelomocytes of sea cucumber Apostichopus japonicus was... more One monoclonal antibody (mAb 3F6) against coelomocytes of sea cucumber Apostichopus japonicus was developed by immunization of Balb/C mice. Analyzed by indirect immunofluorescence assay test (IIFAT), immunocytochemical assay (ICA), Western blotting and fluorescenceactivated cell sorter (FACS), mAb 3F6 showed specific for spherulocytes of A. japonicus. The mAb 3F6 recognized an antigen of molecular weight 136kDa in Western blotting. Isotype analysis
Protozoan Ichthyophthirius multifiliis Fouquet (Ich) and bacterium Aeromonas hydrophila are two c... more Protozoan Ichthyophthirius multifiliis Fouquet (Ich) and bacterium Aeromonas hydrophila are two common pathogens of cultured fish, which cause high fish mortality. Currently there is no information available for the effect of parasitism by Ich on survival of channel catfish and invasion of A. hydrophila in fish tissues following exposure to A. hydrophila. A trial was conducted in this study to: (1) determine whether A. hydrophila increased fish mortality in Ich-parasitized channel catfish; and (2) compare the bacterial quantity in different tissues between non-parasitized and Ich-parasitized catfish by real-time polymerase chain reaction (qPCR). The results demonstrated that the Ich-parasitized catfish showed significantly (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05) higher mortality (80%) when exposed to A. hydrophila by immersion than non-parasitized fish (22%). Low mortality was observed in catfish exposed to Ich alone (35%) or A. hydrophila alone (22%). A. hydrophila in fish tissues were quantified by qPCR using a pair of gene-specific primers and reported as genome equivalents per mg of tissue (GEs/mg). Skin, gill, kidney, liver and spleen in Ich-parasitized fish showed significantly higher load of A. hydrophila (9400-188,300 GEs/mg) than non-parasitized fish (4700-42,100 GEs/mg) after exposure to A. hydrophila. This study provides evidence that parasite infections enhance bacterial invasion and cause high fish mortality.
Previous measles elimination goals have failed in the United States despite high coverage of scho... more Previous measles elimination goals have failed in the United States despite high coverage of schoolchildren with a single dose of measles vaccine. Since 1989 advisory groups have recommended that schoolchildren receive a second dose of measles vaccine as part of a revised strategy to eliminate measles from the US. States have responded by phasing in requirements for a second dose of measles vaccine at school entry for various age groups at primary school entrance, secondary school entrance or both. The purpose of this analysis was to evaluate the effectiveness of the requirements for a second dose of measles vaccine and to determine whether a primary or secondary school entrance requirement was more effective in lowering measles incidence. Using national surveillance data we examined the influence of state requirements for the second dose of measles vaccine on measles incidence from 1993 through 1995. Overall measles incidence was lower in states that had a requirement for a second dose of measles vaccine at either primary school entrance [relative risk (RR) = 0.35; 95% confidence interval, 0.25 to 0.49] or secondary school entrance (RR = 0.38; 95% confidence interval 0.29 to 0.50), compared with states without a second dose requirement. Incidence was lowest in states that required a second dose of measles vaccine at both primary and secondary school entrance (RR = 0.22; 95% confidence interval, 0.13 to 0.37). Our findings demonstrate that a requirement for a second dose of measles vaccine at either primary or secondary school entrance is effective in lowering measles incidence, with a greater reduction occurring in states where the second dose is required for both age groups.
... Cutaneous antibodies have been found to be involved in protection against pathogens (Lobb &am... more ... Cutaneous antibodies have been found to be involved in protection against pathogens (Lobb &amp;amp; Clem 1981; Lobb 1987; Rambout, Taverne, van ... lymphocytes locally in the skin or by lymphoid tissues located outside the skin and transported to the epithelium (Dickerson &amp;amp; Clark ...
Abstract Hybrid striped bass (Morose saxatilis male× M. chrysops female) were injected with 25 an... more Abstract Hybrid striped bass (Morose saxatilis male× M. chrysops female) were injected with 25 and 50 mg oxytetracycline (OTC) per kg of fish. Rate of elimination of OTC from muscle tissue and inhibition of bacteria by muscle injected with OTC were studied. OTC residue in ...
There is limited information on whether parasites act as vectors to transmit bacteria in fish. In... more There is limited information on whether parasites act as vectors to transmit bacteria in fish. In this study, we used parasite Ichthyophthirius multifiliis and fluorescent bacterium Edwardsiella ictaluri as a model to study the interaction between parasite, bacterium and fish. The theronts after exposure to E. ictaluri showed significantly higher fluorescing bacteria (23-39 %) than control theronts (~6 %). Theronts exposed to E. ictaluri at 4 × 107 CFU mL-1 showed a higher percentage (~60 %) of fluorescent theronts compared to those (42 %) exposed to 4 × 103 CFU mL-1 at 4 h. All tomonts (100 %) carried the bacterium after exposure to E. ictaluri. E. ictaluri survived and replicated during tomont division. Confocal microscopy demonstrated E. ictaluri was associated with the tomont surface. Among theronts released from tomonts exposed to E. ictaluri, 31 – 66 % was observed with attached E. ictaluri. Sixty percent of fish exposed to theronts treated with 5×107 E. ictaluri mL-1 were pos...
… . Annu. Conf. Southeast. Assoc. Fish and …, 1995
Abstract: Human chorionic gonadotropin (HCG) is often used to induce spawning offish. However, th... more Abstract: Human chorionic gonadotropin (HCG) is often used to induce spawning offish. However, the US Food and Drug Administration has not approved HCG for use in fish because they claim additional efficacy data are required. Efficacy of HCG for spawning ...
The influence of cooking (frying, baking, and smoking) on dieldrin and 1,1-dichloro-2,2-bis[4-chl... more The influence of cooking (frying, baking, and smoking) on dieldrin and 1,1-dichloro-2,2-bis[4-chlorophenyl]ethylene (DDE) residues in treated channel catfish (Ictalarus punctatus) was determined. Dieldrin and DDE were significantly reduced (P < 0.05) during cooking of catfish by 50 to 65% (dry basis) and 50 to 80%, respectively. Smoking resulted in maximum reduction (82%) of DDE residues, while baking resulted in the least reductions for both dieldrin (50%) and DDE (50%) when compared to the other preparation methods.
One monoclonal antibody (mAb 3F6) against coelomocytes of sea cucumber Apostichopus japonicus was... more One monoclonal antibody (mAb 3F6) against coelomocytes of sea cucumber Apostichopus japonicus was developed by immunization of Balb/C mice. Analyzed by indirect immunofluorescence assay test (IIFAT), immunocytochemical assay (ICA), Western blotting and fluorescenceactivated cell sorter (FACS), mAb 3F6 showed specific for spherulocytes of A. japonicus. The mAb 3F6 recognized an antigen of molecular weight 136kDa in Western blotting. Isotype analysis
Protozoan Ichthyophthirius multifiliis Fouquet (Ich) and bacterium Aeromonas hydrophila are two c... more Protozoan Ichthyophthirius multifiliis Fouquet (Ich) and bacterium Aeromonas hydrophila are two common pathogens of cultured fish, which cause high fish mortality. Currently there is no information available for the effect of parasitism by Ich on survival of channel catfish and invasion of A. hydrophila in fish tissues following exposure to A. hydrophila. A trial was conducted in this study to: (1) determine whether A. hydrophila increased fish mortality in Ich-parasitized channel catfish; and (2) compare the bacterial quantity in different tissues between non-parasitized and Ich-parasitized catfish by real-time polymerase chain reaction (qPCR). The results demonstrated that the Ich-parasitized catfish showed significantly (P&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05) higher mortality (80%) when exposed to A. hydrophila by immersion than non-parasitized fish (22%). Low mortality was observed in catfish exposed to Ich alone (35%) or A. hydrophila alone (22%). A. hydrophila in fish tissues were quantified by qPCR using a pair of gene-specific primers and reported as genome equivalents per mg of tissue (GEs/mg). Skin, gill, kidney, liver and spleen in Ich-parasitized fish showed significantly higher load of A. hydrophila (9400-188,300 GEs/mg) than non-parasitized fish (4700-42,100 GEs/mg) after exposure to A. hydrophila. This study provides evidence that parasite infections enhance bacterial invasion and cause high fish mortality.
Previous measles elimination goals have failed in the United States despite high coverage of scho... more Previous measles elimination goals have failed in the United States despite high coverage of schoolchildren with a single dose of measles vaccine. Since 1989 advisory groups have recommended that schoolchildren receive a second dose of measles vaccine as part of a revised strategy to eliminate measles from the US. States have responded by phasing in requirements for a second dose of measles vaccine at school entry for various age groups at primary school entrance, secondary school entrance or both. The purpose of this analysis was to evaluate the effectiveness of the requirements for a second dose of measles vaccine and to determine whether a primary or secondary school entrance requirement was more effective in lowering measles incidence. Using national surveillance data we examined the influence of state requirements for the second dose of measles vaccine on measles incidence from 1993 through 1995. Overall measles incidence was lower in states that had a requirement for a second dose of measles vaccine at either primary school entrance [relative risk (RR) = 0.35; 95% confidence interval, 0.25 to 0.49] or secondary school entrance (RR = 0.38; 95% confidence interval 0.29 to 0.50), compared with states without a second dose requirement. Incidence was lowest in states that required a second dose of measles vaccine at both primary and secondary school entrance (RR = 0.22; 95% confidence interval, 0.13 to 0.37). Our findings demonstrate that a requirement for a second dose of measles vaccine at either primary or secondary school entrance is effective in lowering measles incidence, with a greater reduction occurring in states where the second dose is required for both age groups.
... Cutaneous antibodies have been found to be involved in protection against pathogens (Lobb &am... more ... Cutaneous antibodies have been found to be involved in protection against pathogens (Lobb &amp;amp; Clem 1981; Lobb 1987; Rambout, Taverne, van ... lymphocytes locally in the skin or by lymphoid tissues located outside the skin and transported to the epithelium (Dickerson &amp;amp; Clark ...
Abstract Hybrid striped bass (Morose saxatilis male× M. chrysops female) were injected with 25 an... more Abstract Hybrid striped bass (Morose saxatilis male× M. chrysops female) were injected with 25 and 50 mg oxytetracycline (OTC) per kg of fish. Rate of elimination of OTC from muscle tissue and inhibition of bacteria by muscle injected with OTC were studied. OTC residue in ...
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