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At least 19 recordsLinked to original sources
PubMed1976

Immunological properties of antivenins. II. Univalent Naja haje antivenin.

A purified Naja haje antivenin was tested against Egyptian N. haje and N. nigricollis venoms, Indian N. naja venom, Iranian N. naja oxiana, Vipera lebetina, and V. persica venoms, and Echis carinatus venom from both Iran and Egypt. The different elapid venoms, with the exception of that of N. naja oxiana, showed a considerable number of identical and similar precipitin components by immunodiffusion and immunoelectrophoresis. On the other hand, only a few identical and partially identical lines were detected when this antiserum was tested against the viper venoms. Cross neutralization tests in mice showed variable degrees of protection by the antiserum against the different venoms studied; there was no direct correlation with the immunodiffusion results.

Antigen-Antibody Reactions↗
PubMed1975

The effects of snake venoms and their neurotoxins on the nervous system of man and animals.

Myasthenia gravis is a subject of tremendous interest ot neurologists. Snake poisoning, however, which gives rise to a clinical picture resembling a myasthenic crisis, has evoked little interest among neurologists. This state of affairs exists partly because most snake bites occur in areas where physicians, let alone neurologists, are not commonly found. Hence, few neurologists have seen a case of snake bite with nervous system involvement. This is unfortunate, because many of the published cases of snake bite are the poorer for the lack of detailed examination and observations that a neurologist might have provided. Not only is the clinical picture of snake envenomation a fascinating one where the neurologist, haematologist, cardiologist, and renal physician can find a common clinical interest, but an understanding of the way in which snake venoms act on the nervous system is of importance to the neurologist since the neurotoxic snake venoms act principally at the neuromuscular junction. They produce a flaccid paralysis of the voluntary muscles and cause death from respiratory obstruction and/or respiratory insufficiency. Like the purified defibrinating fraction("Arvin") of the venom of the Malayan pit viper (Agkistrodon rehodostoma), which is currently being used and evaluated as an anticoagulant, the thereapeutic possibilities of a purified neurotoxin that could produce a flaccid paralysis lasting two days or more were anticipated well before 1891 by Lauterer, who, as a result of his experiments, "injected viper poison...under the skin of a boy suffering from tentanus treaumaticus (lockjaw) and slackened the muscles of the whole body by it." This chapter will initially describe the clinical picture of nervous system involvement in snake bite, with particular emphasis on Australian snake bite. The description will be based on observations made at the Port Moresby General Hospital over a period of seven years on 56 patients with paralysis following snake bite, and on some published cases of Australian snake bite. The discussion will then cover some of the recent published work on the action of snake venoms on the nervous system, dealing mainly with elapid venoms. There are several recent reviews describing the toxic properties and actions of all types of snake venoms.

Animals↗
PubMed1976

Snake venom proteinase inhibitors. III. Isolation of five polypeptide inhibitors from the venoms of Hemachatus haemachatus (Ringhal's corbra) and Naja nivea (Cape cobra) and the complete amino acid sequences of two of them.

Five proteinase inhibitors which all inhibit the activity of bovine trypsin [EC 3.4.21.4] were isolated from African Elapid venoms of Hemachatus haemachatus (HHV, Ringhal's cobra) and Naja nivea (NNV, Cape cobra). All the inhibitors were essentially homogeneous by polyacrylamide gel electrophoresis in the presence or absence of sodium dodecylsulfate. Amino acid analysis and terminal analysis also supported their chemical homogeneities, except for one of the two inhibitors from Hemachatus haemachatus venom. The isolated inhibitors had a molecular weight of about 6,500, consisting of 52 to 57 amino acid residues, and they were all devoid of tryptophan. However, their amino acid compositions differed from each other. One of the three inhibitors isolated from Naja nivea venom, designated NNV inhibitor Ia, was unique, in that 4 half-cystinyl residues per mole fof the polypeptide were present, whereas all the others contained six residues. Of the isolated proteinase inhibitors, the complete amino acid sequences of two major inhibitors were established by manual and automatic Edman degradations and standard enzymatic techniques. Each of the inhibitors, designated HHV inhibitor II and NNV inhibitor II, consisted of 57 amino acid with arginine and glycine at the NH2- and COOH-termini, respectively. Both contained six half-cystines in disulfide linkages, and their overall amino acid sequences were similar, showing 91% homology. The two inhibitors differed in sequence by only five amino acid replacements, Asp-3 to Arg; Tyr-17 to Arg; Leu-25 to Arg; Gln-32 to Glu; and Arg-52 to His, in the 57 residue peptide chain. Comparing the amino acid sequences of these two cobra venom inhibitors with those of Russell's viper venom inhibitor II and bovine pancreatic trypsin inhibitor (BPTI), about 50% homology was found in their sequences. The 6 half-cystinyl residues of these inhibitors were in the same linear positions. Moreover, the regions which are structurally and functionally important in the well-known BPTI molecule were found with extremely high sequence homology in the cobra venom inhibitors. These findings strongly suggest that the cobra venom inhibitors as well as Russell's viper inhibitor II have very similar conformations to that established for BPTI.

Amino Acid Sequence↗
PubMed1978

The production and control of anti--venous sera.

This paper describes the species of venomous snakes found in Costa Rica as well as anti-venom sera prepared by the Instituto Clodomiro Picado: polyvalent sera for use in human or veterinary medicine, and anti-Micrurus and anti-Lachesis monovalent sera. These sera are prepared in horses, purified with ammonium sulphate, then concentrated and delivered either in liquid or freeze-dried form. Controls are in accordance with NIH recommendations. For cases of hypersensitivity to horse serum, a polyvalent anti-Bothrops and anti-Crotalus serum from sheep has been prepared.

Americas↗
PubMed1977

The kidney in tropical snakebite.

Renal pathological changes were studied by renal biopsy in 31 patients bitten by tropical poisonous snakes which included seasnake (2 cases), cobra (11 cases), green-pit viper (8 cases) and Russell's viper (10 cases). Renal failure was present only in patients bitten by seasnake and Russell's viper. Glomerular mesangial proliferation was noted in the victims of cobra, green-pit viper and Russell's viper. There was deposition of IgM AND C3 in the glomerular mesangium with extension along the capillary walls. Fibrin deposition was seen in green-pit viper cases. By electron microscopy electron dense deposits were observed in the glomerular basement membrane-like matrix. Irregular thickening of the basement membrane was found in cobra cases. Vascular changes included arteritis of the interlobular artery with C3 deposition in the arterial walls in Russell's viper cases and thrombophlebitis in both green-pit viper's and Russell's viper's victims. Dense deposits of C3 in the arteriolar walls were noted in viper-bite and cobra-bite. Tubular necrosis was demonstrated in patients envenomated by green-pit viper and Russell's viper. Necrosis was severe in seasnake and Russell's viper poisoning, but was mild in green-pit viper cases.

Adolescent↗
PubMed1977

Effects of Sr2+ and Mg2+ on the phospholipase A and the presynaptic neuromuscular blocking actions of beta-bungarotoxin, crotoxin and taipoxin.

1.beta-Bungarotoxin, crotoxin and taipoxin, presynaptic neurotoxins of snake venom origin, have about the same phospholipid-splitting activities as a much less toxic cobra phospholipase A2 in the presence of Ca2+ and deoxycholate. 2. Sr2+ was a much less effective activator of the enzymes than is Ca2+, the activation by Sr2+ being only 3-6% for beta-bungarotoxin and crotoxin and 12% for taipoxin. 3. Sr2+ also inhibited the Ca2+ -activated enzymes by 80% in the cases of beta-bungarotoxin and crotoxin, but only 16% in the case of taipoxin. 4. Mg2" had no significant effect on beta-bungarotoxin or crotoxin, but activated taipoxin in the presence or absence of Ca2". 5. In Sr2+ -Tyrode lacking Ca2+ all three toxins exhibited the same immediate depression followed by facilitation in the rat and mouse diaphragms, but the final blocking activity was only 3-10% with beta-bungarotoxin and crotoxin and was 30% with taipoxin. 6. In Sr2+ -Tyrode, increasing in the rate of nerve stimulation had less accelerating effect on the development of neuromuscular block than in Ca2+ -Tyrode for any of the toxins. 7. Removal of Mg2+ from Sr2+ -Tyrode did not diminish the potency of taipoxin in blocking neuromuscular transmission, suggesting that enzyme activity at the outer surface of the axolemma does not contribute to the neuromuscular blocking action. 8. All of the results indicate that there are close correlations between the presynaptic activities of these toxins and their phospholipid-splitting activities in the cationic environment prevailing in the axoplasm. Apparently the final blocking effect of these toxins is due to phospholipase A action within the nerve terminal.

Animals↗
PubMed1978

Distinct protein components from Torpedo marmorata membranes carry the acetylcholine receptor site and the binding site for local anesthetics and histrionicotoxin.

Highly purified subsynaptic membrane fragments prepared from Torpedo marmorata electric organ (specific activity, greater than 4 mumol of Naja nigricollis alpha-[3H]toxin per mg of protein) exhibit, on sodium dodecyl sulfate/polyacrylamide gel electrophoresis, two major protein bands of apparent molecular weight 40,000 and 43,000, respectively. Dissolution of these membranes by the nondenaturing detergents Triton X-100 and Berol 043 followed by standard fractionation yielded (i) the 9S acetylcholine-receptor protein which still binds the alpha-[3H]toxin and after further purification yielded, in the presence of sodium dodecyl sulfate, the 40,000-dalton component, covalently labeled by the affinity reagent 4-(N-maleimido)phenyl[3H]trimethylammonium; only serine was found as the NH2-terminal amino acid of this protein; and (ii) a high molecular weight aggregate named 43,000 protein which was resolved in denaturing gels almost exclusively as the 43,000-dalton band, In the absence of detergents, the 43,000 protein binds compounds known to interact with the acetylcholine ionophore: a fluorescent local anesthetic quinacrine and histrionicotoxin (apparent dissociation constant, 7 +/- 1 X 10(-7) M). The regulation of quinacrine fluorescennce by carbamylcholine, observed in the intact membrane, no longer occurs with the isolated 43,000 component.

Amino Acids↗
PubMed1977

Identification and neutralization of biological activities associated with venom from the brown recluse spider, Loxosceles reclusa.

Venom from the brown recluse spider, Loxosceles reclusa, reacted with human erythrocytes to form venom-sensitized erythrocytes. These cells were agglutinated specifically by high dilutions of adsorbed rabbit antivenin or were lysed by normal blood group compatible human sera. The specific rabbit antivenin prevented venom from attaching to erythrocytes, from interacting with serum complement, and from producing dermonecrotic lesions in rabbits. Results of experiments involving heat inactivation and adsorption to erythrocytes provide circumstantial evidence to suggest that the three biological activities of venom could be associated with a single component or few components with similar properties. The component interacting with serum complement is immunologically distinct from a factor in cobra venom which possesses similar biological activities.

Animals↗