ABSTRACT
The aim of this study was a preliminary investigation on the possibility of using the ephyra of Scyphozoan jellyfish Aurelia aurita (Linnaeus, 1758), the common moon jellyfish, as an innovative model organism in marine ecotoxicology. A series of sequential experiments have been carried out in laboratory in order to investigate the influence of different culturing and methodological parameters (temperature, photoperiod, ephyrae density and age) on behavioural end-points (% of Frequency of Pulsations) and standardize a testing protocol. After that, the organisms have been exposed to two well known reference toxic compounds (Cadmium Nitrate and SDS) in order to analyse the acute and behavioural responses during static exposure. Results of this work indicate that the proposed behavioural end-point, frequency of pulsations (Fp), is an easily measurable one and can be used coupled with an acute one (immobilization) and that ephyrae of jellyfish are very promising model organisms for ecotoxicological investigation.
Subject(s)
Cadmium Compounds/toxicity , Ecotoxicology/methods , Models, Animal , Nitrates/toxicity , Scyphozoa/drug effects , Sodium Dodecyl Sulfate/toxicity , Animals , Biological Assay , Photoperiod , Scyphozoa/physiology , Swimming , TemperatureABSTRACT
Bovine erythrocytes infected with Anaplasma marginale were standardized with normal bovine erythrocytes at 1.4% and 3.5% parasitemia and cultured under low oxygen pressure at 37 C. The number of erythrocytes infected by A marginale appeared to increase 3.3-fold by day 11 and 4.5-fold by day 3, as determined by microscopic examination of Giemsa-stained thin films of the culture suspension. Anaplasma parasites in experimental cultures were proven to be viable and pathogenic by calf inoculation for up to 16 days.
Subject(s)
Anaplasma/growth & development , Erythrocytes/microbiology , Anaplasma/isolation & purification , Anaplasmosis/microbiology , Animals , Cattle , Cattle Diseases/microbiology , Cells, CulturedABSTRACT
Anaplasma marginale was seen by electron microscopy within the cytoplasm of Aedes albopictus cells in culture. Anaplasma marginale was seen in free bovine RBC as well as in RBC phagocytized by Ae albopictus cells. Some A marginale organisms, both intracellular and extracellular, remained intact for as long as 60 days in culture, and Anaplasma inclusion appendages were seen in free-lysed RBC and in lysed RBC phagocytized by Ae albopictus cells. Although some A marginale organisms had deteriorated by day 60, the structure of most A marginale organisms did not change appreciably from that in its natural bovine host. Reproduction of A marginale was not seen.
Subject(s)
Aedes/parasitology , Anaplasma/ultrastructure , Anaplasma/growth & development , Animals , Cattle , Culture Techniques , Cytoplasm , Erythrocytes/parasitology , Fetal Blood/parasitology , Microscopy, Electron , PhagocytosisABSTRACT
New Zeland White rabbits inoculated with Anaplasma marginale-infected bovine erythrocytes produced specific humoral antibodies to this parasite. Specific antibody production as measured by the card and complement-fixation (CF) tests was maximal in 7 to 21 days after inoculation; however, none of the rabbits became infected. Geometric mean CF titers of rabbits inoculated with RBC from cattle with acute anaplasmosis were significantly higher (P less than 0.001) than those of rabbits given RBC from normal cattle. Significant difference was not seen between geometric mean CF titers of rabbits given RBC from carrier cattle and those of rabbits given RBC from normal cattle. It is concluded, therefore, that rabbit inoculations cannot effectively be substituted for calf inoculations to determine the anaplasmosis status of carrier cattle.
Subject(s)
Anaplasmosis/diagnosis , Erythrocytes/microbiology , Rabbits/immunology , Agglutination Tests , Anaplasmosis/immunology , Anaplasmosis/microbiology , Animals , Antibodies, Bacterial/analysis , Blood/microbiology , Cattle , Cattle Diseases/diagnosis , Complement Fixation Tests , Immunoelectrophoresis , Rabbits/bloodABSTRACT
Bovine red blood cells infected with Anaplasma marginale were introduced into cell line cultures from the mosquito Aedes albopictus. The cultured mosquito cells phagocytized both infected and uninfected red blood cells. The parasite remained viable, as determined by calf inoculations, for 21 days.
Subject(s)
Aedes/microbiology , Anaplasma/growth & development , Anaplasmosis/microbiology , Animals , Cattle , Cattle Diseases/microbiology , Cells, Cultured , Erythrocytes/microbiology , PhagocytosisABSTRACT
After the application in vitro of (14)C amylopectin sulphate solution to frozen sections of human ulcer-bearing stomach, autoradiography demonstrates localization of amylopectin sulphate to the gastric surface. The affinity of amylopectin sulphate macromolecule for the gastric luminal surface would provide a substrate-bound pepsin inhibitor with a molecular sieve-like action to exclude proteolytic enzymes from the mucosal surface. This protective coating action may mimic the hypothetical role of endogenous gastric mucous substances and account for the action of amylopectin sulphate in human peptic ulcer.
