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Chemical modifications of equinatoxin II
8th European Symposium-Abstracts
167
was caused by the hyperactivity of the motoneurones in the early period. At the later period, the muscles) had (have) no electro-myographic activity . The muscle was in the state of contracture . When tetanus toxin is injected i.v ., the muscles of the whole body are highly activated (general tetanus) . In heavy general tetanus many kinds of spinal inhibition were kept intact . Thus local and general tetanus are different in their nature. Therefore general tetanus can not be the sum of the local tetanus as supposed previously . Clinical tetanus is the sum of general and local tetanus. The spinal cord is not the main target organ in clinical tetanus which mainly consists of general tetanus.
Applied immrmalogy in snake venom research . R . D. G. Tr~KS'ront (Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 SQA, U.K .) .
ENZYME-LINKED 1mmuIIOSOrbent assay (ELISA) has proved to be a very important tool for studying both the epidemiology and clinical effects of snake bite in man. For epidemiology, ELISA depends on the development and persistence of specific humoral venom antibody in previous snake bite victims. In the Nigerian savanna 65% of previous bite victims possessed specific venom antibodies against Echis carinates venom; in Ecuador 78% of a population of Waorani Indians possessed venom antibody against a wide range of different venoms which were identified using ELISA. In certain areas it is often not possible, using the symptoms of envenoming, to determine which species of snake has bitten the patient. Results obtained in field studies in Nigeria and Thailand have demonstrated the success in establishing the species responsible for envenoming. Current studies are in progress on the development of a rapid immunoassay which should be capable of detecting the biting species within 5 minutes of sampling from the admission patient. This will be useful for the clinician in that he will be able to rapidly detect the species responsible for envenoming and therefore treat the patient with the correct antivenom. Experimental work on the development of new methods of andvenom production utilises immunization of experimental animals using venomJliposome preparations and the preparation of venom antigens using monoclonal antibodies on affinity columns and recombinant DNA technology . Liposomal immunization requires only a single injection of venom to obtain a rapid, high level and protective immune response . Venom liposomes may also be given orally resulting in a serum IgG immune response in experimental animals. The potential of such a system in man may result in eventual immunization of man in areas of high snake bite incidence and mortality. Vipers aspic bite: report of an uxesual case. FEDERICH TORxeclAxr,' Coxrun~ L~ CwE1u' and ALE43ANDRA McRCEw~RO~ ('Cattedra di Tossicologia Forense, University di Genova, I-16132 Genova, Italy, and ZDivisione di Medicine Generale, Presidio Ospedaliero USSL 17, I-16038 Santa Margherita Ligure (GE), Italy) .
Vipers aspic is the most poisonous, widespread and numerous snake in Italy; all the most recent cases of death by snake bite are attributed to this species, and each year accounts for 72% of all viper bites (Pouo, 1988). The Authors describe the case of a woman of 80 years of age, who was bitten on the 27th of October 1988 on the back of the right hand by a Vipers aspic. The viper was twisted on a branch of a tree, that stuck out at the height of the woman's head and that she had tried to move with the hand. This case presents some interesting aspects, previously described in literature, like We delay time of the bite, the absence of pain after the bite, the scarce effectiveness of i.v . serotherapy on the progression of the local symptomatology . This communication constitutes the second European report of viper bite verified on a branch of a tree ; an eventuality never reported for Vipers aspic. The first European report concerns Vipers latasti, which also seems to have an arboreal habitat. TILE IiAL1AN viper,
Chemical modifications of equinatoxin II. T. TtrnK and P. McL~EIC (Biotechnical Faculty, Department of Biology and Institute of Biology, Edvard Kardelj University, Ljubljana, Yugoslavia).
Tlfls wrrrluatrnox represents a review of chemical modifications in Equinatoxin II molecule. Carboxyl groups, N-terminal serine residue, tyrosine, tryptophan, arginine, histidine and lysine residues were modified with groupspecific reagents . The effect of each chemical modification on biological and physiwchemical properties of the toxin was monitored and compared with the native toxin. Biological activity of Equinatoxin II was assayed with hemolytic tests, lethal activity in NIH mice and precipitation with human serum lipoproteins . Physicochemical properties of modified toxins were monitored by means of u.v ., c.d. and fluorescence spectroscopy, iscelectric focusing and solubility . Our results suggest that tyrosine and probably tryptophan are essential for toxin hemolytic and lethal activity, while modification of carboxyl groups abolished only toxin lethal activity . Other modified amino acids are not essential for either toxin activity although some physico-chemical properties are significantly altered due to chemical modification of lysine or histidine residues .
167
was caused by the hyperactivity of the motoneurones in the early period. At the later period, the muscles) had (have) no electro-myographic activity . The muscle was in the state of contracture . When tetanus toxin is injected i.v ., the muscles of the whole body are highly activated (general tetanus) . In heavy general tetanus many kinds of spinal inhibition were kept intact . Thus local and general tetanus are different in their nature. Therefore general tetanus can not be the sum of the local tetanus as supposed previously . Clinical tetanus is the sum of general and local tetanus. The spinal cord is not the main target organ in clinical tetanus which mainly consists of general tetanus.
Applied immrmalogy in snake venom research . R . D. G. Tr~KS'ront (Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 SQA, U.K .) .
ENZYME-LINKED 1mmuIIOSOrbent assay (ELISA) has proved to be a very important tool for studying both the epidemiology and clinical effects of snake bite in man. For epidemiology, ELISA depends on the development and persistence of specific humoral venom antibody in previous snake bite victims. In the Nigerian savanna 65% of previous bite victims possessed specific venom antibodies against Echis carinates venom; in Ecuador 78% of a population of Waorani Indians possessed venom antibody against a wide range of different venoms which were identified using ELISA. In certain areas it is often not possible, using the symptoms of envenoming, to determine which species of snake has bitten the patient. Results obtained in field studies in Nigeria and Thailand have demonstrated the success in establishing the species responsible for envenoming. Current studies are in progress on the development of a rapid immunoassay which should be capable of detecting the biting species within 5 minutes of sampling from the admission patient. This will be useful for the clinician in that he will be able to rapidly detect the species responsible for envenoming and therefore treat the patient with the correct antivenom. Experimental work on the development of new methods of andvenom production utilises immunization of experimental animals using venomJliposome preparations and the preparation of venom antigens using monoclonal antibodies on affinity columns and recombinant DNA technology . Liposomal immunization requires only a single injection of venom to obtain a rapid, high level and protective immune response . Venom liposomes may also be given orally resulting in a serum IgG immune response in experimental animals. The potential of such a system in man may result in eventual immunization of man in areas of high snake bite incidence and mortality. Vipers aspic bite: report of an uxesual case. FEDERICH TORxeclAxr,' Coxrun~ L~ CwE1u' and ALE43ANDRA McRCEw~RO~ ('Cattedra di Tossicologia Forense, University di Genova, I-16132 Genova, Italy, and ZDivisione di Medicine Generale, Presidio Ospedaliero USSL 17, I-16038 Santa Margherita Ligure (GE), Italy) .
Vipers aspic is the most poisonous, widespread and numerous snake in Italy; all the most recent cases of death by snake bite are attributed to this species, and each year accounts for 72% of all viper bites (Pouo, 1988). The Authors describe the case of a woman of 80 years of age, who was bitten on the 27th of October 1988 on the back of the right hand by a Vipers aspic. The viper was twisted on a branch of a tree, that stuck out at the height of the woman's head and that she had tried to move with the hand. This case presents some interesting aspects, previously described in literature, like We delay time of the bite, the absence of pain after the bite, the scarce effectiveness of i.v . serotherapy on the progression of the local symptomatology . This communication constitutes the second European report of viper bite verified on a branch of a tree ; an eventuality never reported for Vipers aspic. The first European report concerns Vipers latasti, which also seems to have an arboreal habitat. TILE IiAL1AN viper,
Chemical modifications of equinatoxin II. T. TtrnK and P. McL~EIC (Biotechnical Faculty, Department of Biology and Institute of Biology, Edvard Kardelj University, Ljubljana, Yugoslavia).
Tlfls wrrrluatrnox represents a review of chemical modifications in Equinatoxin II molecule. Carboxyl groups, N-terminal serine residue, tyrosine, tryptophan, arginine, histidine and lysine residues were modified with groupspecific reagents . The effect of each chemical modification on biological and physiwchemical properties of the toxin was monitored and compared with the native toxin. Biological activity of Equinatoxin II was assayed with hemolytic tests, lethal activity in NIH mice and precipitation with human serum lipoproteins . Physicochemical properties of modified toxins were monitored by means of u.v ., c.d. and fluorescence spectroscopy, iscelectric focusing and solubility . Our results suggest that tyrosine and probably tryptophan are essential for toxin hemolytic and lethal activity, while modification of carboxyl groups abolished only toxin lethal activity . Other modified amino acids are not essential for either toxin activity although some physico-chemical properties are significantly altered due to chemical modification of lysine or histidine residues .