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Immunological cross-activity and neutralizing capacity of the antiserum to the venom of the king brown snake (Pseudechis aastralis)
Eleventh World Congress
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on histamine release as the hematopoietic growth factor IL-3. Thus the nonneuronal effects of cobra NGF may account for immunomodulatory activities essential for wound healing and tissue repair. Antitumoral activity in an organic extract of the sea anemone Bunodosoma caissarum. E. L. A. Malpezzi, ~ D. H. Matsui, 2 S. C. T. S. Groote) J. C. Freitas, I G. M. Santelli 2 and J. B. Fernandes3 (I Department of Physiology, Biosciences Institute and Marine Biology Center, and 2Department of Histology and Embryology, Biomedical Sciences Institute, University of Silo Paulo, 05508-900, S~o Paulo, Brazil; and 3Department of Chemistry, Federal University of Sao Carlos, Brazil). in a previous work, Malpezzi and Freitas (1990) demonstrated that Bunodosoma caissarum hydroalcohol extract has antimitot:c activity on sea urchin egg development. To identify the active substances, the extract was fractioned by partition and adsorption on silica gel. The partition using methylene chloride, n-butanol, methanol and water, lX,rmitted the separation of lipids from the higher polarity compounds. The assays consisted of incubation of each fraction (4.9 mg/ml) with washed sea urchin eggs in 10 ml of filtered sea water with constant shaking at room temperature (22 + 4°C). From each flask 100 cells were counted to obtain the percentage of mitosis related to control. Lipid fraction (methylene chloride, ninhidrin negative) and n-butanol fraction (ninhidrin positive) showed 100% antimitotic action when applied before or after fertilization. Fractionation of methylene chloride phase by adsorption on silica gel with methylene chloride, ethyl acetate, methanol and water elutions show~ antimitotic activity in the lipid fractions with higher polarity. The fraction eluted with methanol also exhibited 100% antimitotic activity in this assay. N-butanol fractions were tested also on T47D cells, derived from human breast carcinoma at concentrations ranging from 50 to 500/zg/ml. The cells were incubated in DMEM:FI0 (l:l) medium containing the extract for 5 days and then counted, showing a dose-dependent inhibition of cell proliferation. The inhibition of DNA synthesis was measured to clarify the action of the compounds, through the ~H-thymidine incorporation followed by radioautography, and we verified a partial blockade (56.6%) of this process. After reversed phase HPLC analysis of the n-butanol fractions (elution with methanol:waler 8:2) three low tool. wt substances were found, and identification by NMR is in progress. Supported by: FAPESP, CNPq, CAPES and FINEP, Brazil. Malpezzi and Freitas (1990) Braz. J. reed. Biol. Res. 23, 8-I 1. Immunological cross-activity and neutralizing capacity of the antiserum to the venom of the king brown snake (Pseudechis aastralis). S. Z. J. Chen, I P. Gopalakrishnakone2 and M. C. E. Gwee I (Venom and Toxin Research Group, Departments of i Pharmacology, and 2Anatomy, National University of Singapore). The cross-activities between the antiserum to the venom from P. australis and some other crude venoms and toxins were determined using the agar gel double diffusion method. The polyclonal antiserum was raised in rabbits and tested against 34 different crude venoms and purified toxins for cross-reactivity. Precipitating lines in agar gel revealed that the antiserum cross-reacted with 21 other venoms and purified toxins, of which 8 were purified fractions from P. australis. The other venoms were from the Pseudechis subfamily, Notechis subfamily, Acanthophis subfamily, and Enhydrina schistosa, and Austrelaps superba. The in vitro neutralizing capacity was also studied using 36 mice. The results showed that every 1.0 ml antiserum was able to neutralize 40-fold LDs0 dose of the venom from P. australis. This study indicated that the rabbit antiserum to the venom from P. australis had significant cross-reactivity with the venoms from the Pseudechis, Notechis and Acanthophis subfamilies. Thus the toxins from P. australis may be homologous with some other toxins in structure or enzymatic activities. Similarly to the notexin, the venom of P. australis also exhibits a variety of phospholipase A 2 activities, which can interfere with neuromuscular function and cause muscle damage or produce myoglobinuria. The antiserum raised in rabbits was able to neutralize the lethal and myotoxic activities of the venom from P. australis and was also paraspecific to many venoms and toxins. The use of arttitoxin for human cases of tick paralysis in Australia: questions and answers/B. F. Stone, I Y. H. Thong ~ and R. T. Gemmell2 (University of Queensland, Departments of 1Child Health, Mater Children's Hospital, South Brisbane 4101, and 2Anatomical Sciences, St Lucia 4067, Australia). The Australian paralysis tick, lxodes holocyclus, arguably the most toxic tick in the world, is perceived largely as a veterinaJT problem rather than a medical one. However, in the first half of this century 20 human deaths were recorded in the State of New South Wales alone. There would probably have been a number of undiagnosed, unrecorded additional cases and perhaps deaths, in New South Wales, Victoria and Queensland, particularly prior to 1900 as the habitat of this tick extends along much of the eastern seaboard from far North Queensland to Victoria. It is believed that enhanced awareness of the dangers of tick paralysis, coupled with the availability of an antitoxin, has resulted in no further mortalities since 1945. Nevertheless, a few life-threatening cases of
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on histamine release as the hematopoietic growth factor IL-3. Thus the nonneuronal effects of cobra NGF may account for immunomodulatory activities essential for wound healing and tissue repair. Antitumoral activity in an organic extract of the sea anemone Bunodosoma caissarum. E. L. A. Malpezzi, ~ D. H. Matsui, 2 S. C. T. S. Groote) J. C. Freitas, I G. M. Santelli 2 and J. B. Fernandes3 (I Department of Physiology, Biosciences Institute and Marine Biology Center, and 2Department of Histology and Embryology, Biomedical Sciences Institute, University of Silo Paulo, 05508-900, S~o Paulo, Brazil; and 3Department of Chemistry, Federal University of Sao Carlos, Brazil). in a previous work, Malpezzi and Freitas (1990) demonstrated that Bunodosoma caissarum hydroalcohol extract has antimitot:c activity on sea urchin egg development. To identify the active substances, the extract was fractioned by partition and adsorption on silica gel. The partition using methylene chloride, n-butanol, methanol and water, lX,rmitted the separation of lipids from the higher polarity compounds. The assays consisted of incubation of each fraction (4.9 mg/ml) with washed sea urchin eggs in 10 ml of filtered sea water with constant shaking at room temperature (22 + 4°C). From each flask 100 cells were counted to obtain the percentage of mitosis related to control. Lipid fraction (methylene chloride, ninhidrin negative) and n-butanol fraction (ninhidrin positive) showed 100% antimitotic action when applied before or after fertilization. Fractionation of methylene chloride phase by adsorption on silica gel with methylene chloride, ethyl acetate, methanol and water elutions show~ antimitotic activity in the lipid fractions with higher polarity. The fraction eluted with methanol also exhibited 100% antimitotic activity in this assay. N-butanol fractions were tested also on T47D cells, derived from human breast carcinoma at concentrations ranging from 50 to 500/zg/ml. The cells were incubated in DMEM:FI0 (l:l) medium containing the extract for 5 days and then counted, showing a dose-dependent inhibition of cell proliferation. The inhibition of DNA synthesis was measured to clarify the action of the compounds, through the ~H-thymidine incorporation followed by radioautography, and we verified a partial blockade (56.6%) of this process. After reversed phase HPLC analysis of the n-butanol fractions (elution with methanol:waler 8:2) three low tool. wt substances were found, and identification by NMR is in progress. Supported by: FAPESP, CNPq, CAPES and FINEP, Brazil. Malpezzi and Freitas (1990) Braz. J. reed. Biol. Res. 23, 8-I 1. Immunological cross-activity and neutralizing capacity of the antiserum to the venom of the king brown snake (Pseudechis aastralis). S. Z. J. Chen, I P. Gopalakrishnakone2 and M. C. E. Gwee I (Venom and Toxin Research Group, Departments of i Pharmacology, and 2Anatomy, National University of Singapore). The cross-activities between the antiserum to the venom from P. australis and some other crude venoms and toxins were determined using the agar gel double diffusion method. The polyclonal antiserum was raised in rabbits and tested against 34 different crude venoms and purified toxins for cross-reactivity. Precipitating lines in agar gel revealed that the antiserum cross-reacted with 21 other venoms and purified toxins, of which 8 were purified fractions from P. australis. The other venoms were from the Pseudechis subfamily, Notechis subfamily, Acanthophis subfamily, and Enhydrina schistosa, and Austrelaps superba. The in vitro neutralizing capacity was also studied using 36 mice. The results showed that every 1.0 ml antiserum was able to neutralize 40-fold LDs0 dose of the venom from P. australis. This study indicated that the rabbit antiserum to the venom from P. australis had significant cross-reactivity with the venoms from the Pseudechis, Notechis and Acanthophis subfamilies. Thus the toxins from P. australis may be homologous with some other toxins in structure or enzymatic activities. Similarly to the notexin, the venom of P. australis also exhibits a variety of phospholipase A 2 activities, which can interfere with neuromuscular function and cause muscle damage or produce myoglobinuria. The antiserum raised in rabbits was able to neutralize the lethal and myotoxic activities of the venom from P. australis and was also paraspecific to many venoms and toxins. The use of arttitoxin for human cases of tick paralysis in Australia: questions and answers/B. F. Stone, I Y. H. Thong ~ and R. T. Gemmell2 (University of Queensland, Departments of 1Child Health, Mater Children's Hospital, South Brisbane 4101, and 2Anatomical Sciences, St Lucia 4067, Australia). The Australian paralysis tick, lxodes holocyclus, arguably the most toxic tick in the world, is perceived largely as a veterinaJT problem rather than a medical one. However, in the first half of this century 20 human deaths were recorded in the State of New South Wales alone. There would probably have been a number of undiagnosed, unrecorded additional cases and perhaps deaths, in New South Wales, Victoria and Queensland, particularly prior to 1900 as the habitat of this tick extends along much of the eastern seaboard from far North Queensland to Victoria. It is believed that enhanced awareness of the dangers of tick paralysis, coupled with the availability of an antitoxin, has resulted in no further mortalities since 1945. Nevertheless, a few life-threatening cases of