Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| cytotoxicity of cobra (naja naja kaouthia) venom on rabbit red blood cells and s-180 tumor cells in the presence of tetracaine, lidocaine and procaine. | the cytocidal action of naja naja kaouthia venom on rabbit red blood cells and s-180 tumor cells treated with local anesthetics (tetracaine, lidocaine and procaine) were studied. the s-180 cells were more sensitive to the venom than the red blood cells which required albumin for efficient hemolysis in the 10 minute assay. all three local anesthetics at lower concentrations protected both cell types against venom hemolysis. at higher concentrations the local anesthetics enhanced the cell lysis to ... | 1980 | 7385945 |
| purification, some properties and amino-acid sequences of two phospholipases a (cm-ii and cm-iii) from naja naja kaouthia venom. | two phospholipases a, cm-ii and cm-iii, were purified from the siamese cobra (naja naja kaouthia) venom, from thailand, by gel filtration on sephadex g-50 followed by ion-exchange chromatography on cm-cellulose. they each comprise 119 amino acid residues including 14 half-cystine residues. the complete primary structures of the two phospholipases a have been elucidated and their sequences are 96% identical. the sequences, the invariant amino acid residues and the sequences around the active cent ... | 1980 | 7460933 |
| snake venoms. the amino acid sequences of two melanoleuca-type toxins. | toxins cm-10 from naja nivea and cm-9a from naja naja kaouthia venoms were purified by gel filtration followed by ion-exchange chromatography. whereas toxin cm-10 contains 65 amino acids, toxin cm-9a contains only 64 but they each include ten half-cystine residues. the complete primary structures of the toxins have been established. the sequences and the invariant amino acids of toxins cm-10 from n. nivea and cm-9a from n.n. kaouthia venoms resemble those of the melanoleuca-type toxins. in the t ... | 1980 | 7380387 |
| the complete primary structures of three cytotoxins (cm-6, cm-7 and cm-7a) from naja naja kaouthia (siamese cobra) snake venom. | 1980 | 7210030 | |
| participation of an ionizable group with pk 8.55 in the reaction of p-bromophenacyl bromide with his 48 of cobra venom phospholipases a2. | the chemical reaction of p-bromophenacyl bromide (bpb) with his 48 of cobra venom phospholipases a2 (n. naja siamensis, n. naja kaouthia, and n. naja atra) was studied at 25 degrees c and ionic strength 0.1 by following the decreases in the fluorescence intensity of 8-anilino-1-naphthalene sulfonate (ans) and/or in the enzymatic activity. the effect of the bpb concentration on the pseudo-first-order rate constant, chi obs, was studied for the n. naja atra enzyme and the dissociation constants of ... | 1982 | 7096315 |
| bindings of cobra venom phospholipases a2 to micelles of n-hexadecylphosphorylcholine. | bindings of cobra venom phospholipases a2 to micelles of n-hexadecylphosphorylcholine were studied by the tryptophyl fluorescence method at 25 degrees c and ionic strength 0.1. the data were analyzed by assuming that the micellar surface has multiple binding sites for the enzyme and these sites are identical and mutually independent. the enzyme binding site was found to accommodate a constant number of substrate (monomer) molecules, n = 10, 5 or 13 for n. naja atra apoenzyme and its ca2+ complex ... | 1983 | 6619110 |
| development of simple standard assay procedures for the characterization of snake venom. | in accordance with the recommendations of the report of a who coordination meeting on venoms and antivenoms, methods have been developed for the assessment of lethal, defibrinogenating, procoagulant, haemorrhagic, and necrotizing properties of venoms, and used to study 53 venoms from 30 different species of snakes of medical importance throughout the world. the venoms studied included echis carinatus (iran), naja naja kaouthia (thailand), notechis scutatus (australia), trimeresurus flavoviridis ... | 1983 | 6609011 |
| proteolytic activities of cobra venoms based on inactivation of alpha 2-macroglobulin. | the venoms of various cobra species showed a wide range of abilities to cleave hide powder azure, with naja naja kaouthia and ophiophagus hannah venoms showing the lowest activities and naja nivea venom showing the greatest activity on this dye-linked substrate. the activities of the venoms on hide powder did not completely correlate with their ability to inactivate the alpha 2-macroglobulin of human serum. incubation of 4-5 micrograms of naja nigricollis venom per microliter of serum for 30 min ... | 1984 | 6197999 |
| cobra venom factor: improved method for purification and biochemical characterization. | a method to purify cobra venom factor (cvf) from cobra venom by sequential column chromatography is described which yields a product virtually free of phospholipase a2, a common contaminant of cvf preparations. the separation of phospholipase a2 from cvf was achieved by chromatography on cibacron blue-agarose, a resin that tightly binds cobra venom phospholipase a2. a rapid and simple hemolytic assay for the qualitative and quantitative determination of cvf based on its ability to induce bystand ... | 1984 | 6491300 |
| hypotensive compounds isolated from the dried body of naja naja kaouthia lesson. i. isolation of inosine as a hypotensive principle and structure-activity study of related compounds. | 1986 | 3719873 | |
| elisa confirmation of acute and past envenoming by the monocellate thai cobra (naja kaouthia). | the monocellate thai cobra (naja kaouthia) is a major cause of snake bite mortality and morbidity throughout thailand, but neither the local nor the systemic effects of its venom are diagnostic. species diagnosis is important because only monospecific antivenoms are available for treatment in thailand. we tested the ability of the elisa technique to detect venom antigen in the sera of 58 acute snake bite cases including 4 fatalities, and venom antibody in 51 patients bitten between 1 month and 1 ... | 1986 | 3946735 |
| contracture induction by snake venom cardiotoxin in skeletal muscle from humans and rats. | contracture responses to cardiotoxin (ctx) from naja naja kaouthia venom were investigated in rat and human skeletal muscle of similar fiber type distribution to determine species differences in mechanism of action. rat diaphragm strips and human vastus lateralis preparations were directly stimulated in a tissue bath. the calcium dependence of toxin action, synergism between ctx and phospholipase a2 (pla2) activity and roles of na+ + k+-atpase activity and the sarcoplasmic reticulum ca2+ stores ... | 1987 | 3433297 |
| factors contributing to fatal snake bite in the rural tropics: analysis of 46 cases in thailand. | records of 46 cases of fatal bites by identified snakes from 15 provincial hospitals throughout thailand contained sufficient information for detailed analysis. bungarus candidus and calloselasma rhodostoma were each responsible for 13 deaths, naja kaouthia for 12, vipera russelli for 7 and b. fasciatus for one. major causes of death among elapid victims were respiratory failure (26) and complications of prolonged mechanical ventilation (10), and among viper victims shock (12), intracranial haem ... | 1988 | 3257001 |
| effects of divalent cations on snake venom cardiotoxin-induced hemolysis and 3h-deoxyglucose-6-phosphate release from human red blood cells. | at a low concentration of naja naja kaouthia cardiotoxin (3 microm) ca2+, sr2+ and ba2+ (2 mm), had little to no effect on 3h-deoxyglucose-6-phosphate (3h-dglu-6-p) or hemoglobin release. at higher concentrations of n. n. kaouthia cardiotoxin (greater than or equal to 10 microm), ca2+ (2 mm), but not sr2+ or ba2+, significantly enhanced 3h-dglu-6-p and hemoglobin release. mn2+ (2 mm) almost completely inhibited 3h-dglu-6-p release and hemolysis at both the 3 microm and 10 microm concentrations o ... | 1989 | 2629171 |
| factors influencing the hemolysis of human erythrocytes by cardiotoxins from naja naja kaouthia and naja naja atra venoms and a phospholipase a2 with cardiotoxin-like activities from bungarus fasciatus venom. | the effects of red blood cell age and incubation conditions (temperature, divalent cation type and concentration, ph and glucose) on hemolysis induced by cardiotoxin fractions from naja naja atra and naja naja kaouthia venoms, a phospholipase a2 with cardiotoxin-like activities from bungarus fasciatus venom and bee venom phospholipase a2 were examined. hemolysis by the snake venom toxins was dependent on red blood cell age (aged more susceptible than fresh) and the temperature of incubation (37 ... | 1989 | 2718193 |
| hemolytic activity of thionin from pyrularia pubera nuts and snake venom toxins of naja naja species: pyrularia thionin and snake venom cardiotoxin compete for the same membrane site. | pyrularia thionin (p. thionin) is a strongly basic peptide of 47 amino acids which is hemolytic, cytotoxic and neurotoxic. it shows the greatest hemolytic activity toward human erythrocytes. rabbit, guinea pig and pig erythrocytes show decreasing activity in that order, and little or no activity is shown with sheep, horse, cow or mouse erythrocytes. crotalus venoms are inactive, but the venoms from naja naja atra, naja naja ceylonicus and naja naja melanoleuca and, more specifically, cardiotoxin ... | 1989 | 2749751 |
| factors in snake venoms that increase capillary permeability. | capillary permeability increasing (cpi) activity is a phenomenon of the microvasculature caused by many agents such as snake venoms, histamine, 5-hydroxytryptamine (5-ht), prostaglandins and leukotrienes. since no systematic study has been done to determine what components of snake venom cause cpi activity, a cpi factor from naja naja atra (taiwan cobra) venom was isolated using intravenous injections of evan's blue dye as the indicator of increased permeability and the factor's properties were ... | 1989 | 2576052 |
| hemolysis of erythrocytes and fluorescence polarization changes elicited by peptide toxins, aliphatic alcohols, related glycols and benzylidene derivatives. | hemolysis rates of human erythrocytes induced by c2 and c8-c14 straight chain 1-alkanols, 1,2-alkanediols and the corresponding benzylidene derivatives (benzaldehyde acetals) have been studied and compared with hemolysis rates obtained by three peptide toxins. the peak of activity occurs at c12 for the alkanols and glycols and at c10 for the benzylidene derivatives. the most active compound is 1-dodecanol, followed by 1,2-dodecanediol and the c10 benzylidene acetal, which show 50% hemolysis at 1 ... | 1990 | 2245210 |
| interactions in red blood cells between fatty acids and either snake venom cardiotoxin or halothane. | phospholipase a2 (pla2) activity enhances snake venom cardiotoxin (ctx)-induced and general anesthetic (halothane)-induced hemolysis of red blood cells. in the case of halothane-induced hemolysis, this effect appears to be related primarily to free fatty acids. in the present study, the interaction between ctxs and halothane and the effects of different free fatty acids on cardiotoxin and halothane-induced hemolysis were examined. the hemolytic actions of halothane and a ctx from naja naja kaout ... | 1990 | 2402762 |
| comparative enzymatic composition of brazilian coral snake (micrurus) venoms. | 1. venoms of 11 coral snake taxa, including micrurus albicinctus, m. corallinus, m. frontalis altirostris, m. f. brasiliensis, m. f. frontalis, m. fulvius fulvius, m. ibiboboca, m. lemniscatus ssp., m. randonianus, m. spixii spixii, and m. surinamensis surinamensis, were examined for 13 enzymatic activities. 2. these were compared with venoms of three outgroup taxa: naja naja kaouthia, bungarus multicinctus, and bothrops moojeni. 3. enzyme activity levels in micrurus venoms were highly variable ... | 1991 | 1662592 |
| effects of a cardiotoxin from naja naja kaouthia venom on skeletal muscle: involvement of calcium-induced calcium release, sodium ion currents and phospholipases a2 and c. | snake venom cardiotoxin (ctx) fractions induce contractures of skeletal muscle and hemolysis of red blood cells. the fractions also contain trace amounts of venom-derived phospholipase a2 (pla2) contamination and activate tissue phospholipase c (plc) activity. the present study examines the mechanisms of action of a ctx fraction from naja naja kaouthia venom in skeletal muscle. sphingosine competitively antagonized ctx-induced red blood cell hemolysis, but not skeletal muscle contractures. ctx r ... | 1991 | 1666202 |
| snake venom cardiotoxins and bee venom melittin activate phospholipase c activity in primary cultures of skeletal muscle. | the effects of cardiotoxin fractions from naja naja kaouthia and naja naja atra snake venoms and synthetic melittin peptide were examined on lipolytic activity in red blood cells and primary skeletal muscle cultures. both native cardiotoxin fractions caused considerable production of free fatty acids in red blood cells. this production was abolished when the fractions were first treated with p-bromophenacyl bromide to reduce the venom phospholipase a2 activity contamination. in equine and human ... | 1991 | 2054159 |
| comparative chromatography of brazilian coral snake (micrurus) venoms. | 1. elution profiles of 11 coral snake venoms, including those of micrurus albicinctus, m. corallinus, m. frontalis altirostris, m. f. brasiliensis, m. f. frontalis, m. fulvius fulvius, m. ibiboboca, m. lemniscatus ssp., m. rondonianus, m. spixii spixii and m. surinamensis surinamensis, were compared using high performance gel filtration and reverse phase media. 2. micrurus venom profiles were compared with those of "outgroup" taxa bothrops moojeni, naja naja kaouthia and bungarus multicinctus. 3 ... | 1991 | 1756614 |
| binding properties of pyrularia thionin and naja naja kaouthia cardiotoxin to human and animal erythrocytes and to murine p388 cells. | pyrularia thionin and snake venom cardiotoxin are strongly basic peptides which induce hemolysis, depolarization of muscle cells and activation of endogenous phospholipase a2. an earlier study of the hemolysis reaction indicated that the two peptides bind to and compete for the same site on human erythrocytes. a recent study examined the hemolysis induced by both peptides as the phosphate and ca2+ content of the reaction mixture was varied. the results of the recent study (vernon, l. p. and roge ... | 1992 | 1509490 |
| [pharmacological study on naja naja kaouthia lesson. iii. effects of 50% ethanolic extracts from liver and gall bladder on phagocytic activity of mouse reticuloendothelial system]. | effects of 50% ethanolic extracts from the liver and the gall bladder of naja naja kaouthia lesson (cob-l or cob-g) were studied on the phagocytic activity of a mouse reticuloendothelial system. the clearance-rate of carbon was shortened by the oral administration of cob-l or cob-g (50 or 200 mg/kg). cob-l or cob-g promoted the phagocytosis of latex by peritoneal macrophages (m phi). furthermore, effects of these extracts on the peritoneal m phi were biochemically investigated using in vitro exp ... | 1992 | 1608042 |
| effect of calcium and phosphate ions on hemolysis induced by pyrularia thionin and naja naja kaouthia cardiotoxin. | pyrularia thionin is a strongly basic bioactive peptide of 47 amino acids isolated from nuts of pyrularia pubera. it is hemolytic, cytotoxic and activates an endogenous phospholipase a2 in 3t3 cells. earlier studies have shown that the cardiotoxin from naja naja kaouthia has similar activities and binds to the same site as pyrularia thionin. since the peptides appear to bind to the phospholipids of cell membranes to elicit their cellular responses, the effect of modifying the electrostatic envir ... | 1992 | 1509489 |
| purification and properties of the l-amino acid oxidase from monocellate cobra (naja naja kaouthia) venom. | 1. the l-amino acid oxidase of the monocellate cobra (naja naja kaouthia) venom was purified to electrophoretic homogeneity. the molecular weight of the enzyme was 112,200 as determined by sephadex g-200 gel filtration chromatography, and 57,400 as determined by sds-polyacrylamide gel electrophoresis. 2. the enzyme had an isoelectric point of 8.12 and a ph optimum of 8.5. it showed remarkable thermal stability, and, unlike many venom l-amino acid oxidase, was also stable in alkaline medium. the ... | 1992 | 1612186 |
| implications of a consensus recognition site for phosphatidylcholine separate from the active site in cobra venom phospholipases a2. | a model structure of naja naja kaouthia cobra venom phospholipase a2 has been constructed by utilizing molecular modeling techniques. analysis of the model and available biochemical data reveal the presence in this enzyme of a putative recognition site for choline derivatives in loop 57-70 made up of residues trp-61, tyr-63, phe-64, and lys-65, together with glu-55. the magnitude and shape of the electrostatic potential in this binding site are approximately 80% similar to that in the mcpc603 an ... | 1992 | 1550815 |
| structural features of carbohydrate moieties in snake venom glycoproteins. | the structures of the carbohydrate moieties of glycoproteins in snake venoms are largely unknown. in the present study, we have analyzed venoms of several species of snakes as well as plasma and tissue glycoproteins from one species of cobra (naja naja kaouthia) by lectin affinity staining of western blots. the data demonstrate that glycoproteins in cobra venom invariably contain terminal alpha-galactosyl residues with negligible proportions of sialic acids. interestingly, however, terminal alph ... | 1992 | 1731789 |
| use of hplc to demonstrate variation of venom toxin composition in the thailand cobra venoms naja naja kaouthia and naja naja siamensis. | the composition of the venoms of naja naja kaouthia and naja naja siamensis from different commercial sources has been investigated using both ion-exchange and reverse-phase high-pressure liquid chromatography (rp-hplc) in order to investigate variation in toxin contents. the venoms contained identical major toxin components, although in different relative concentrations. the venom collected separately from the left and right glands of individual snakes were virtually the same as judged by rp-hp ... | 1992 | 1595079 |
| influence of chemistry in immobilization of cobra venom phospholipase a2: implications as to mechanism. | phospholipase a2 from naja naja kaouthia venom was covalently coupled onto agarose beads using two different chemistries. the effect of micellar competitive inhibitors in the coupling media was evaluated. enzyme bound to n-hydroxysuccinimide-activated agarose, which is reactive primarily toward epsilon-amino groups, had 20% activity retention against micellar diheptanoylphosphatidylcholine (dic7-pc). enzyme bound through carboxylic groups, using a modification of the carbodiimide method, had 50% ... | 1993 | 8347610 |
| snakebites at maharat nakhon ratchasima regional hospital. | one hundred and ninety-nine victims of snakebite hospitalized at maharat nakhon ratchasima hospital between 1898 and 1991 were studied. the male:female ratio was 1.9:1 and their mean age (+/- sd) was 30.0 +/- 18.6 years. the most common of victims were farmers and laborers. dead snakes were identified as follows: 72 were trimeresurus sp. (36.2%), 36 were naja kaouthia (17.6%), 4 were bungarus fasciatus (2.0%), 1 were colloselasma rhodostoma (0.5%) and 1 was vipera russelli (0.5%). no death was n ... | 1993 | 8362295 |
| species difference in modulation of calcium release by naja naja kaouthia snake venom cardiotoxin in terminal cisternae from human and equine skeletal muscle. | the modulation of ca2+ release by a cardiotoxin (ctx) from naja naja kaouthia snake venom was examined in terminal cisternae-containing fractions from equine and human skeletal muscle. pretreatment with ctx (10 microm) decreased by 27% (human muscle), or had no effect on (equine muscle), the threshold of ca(2+)-induced ca2+ release. if terminal cisternae fractions were first preloaded with ca2+ to greater than 65% of the threshold of ca(2+)-induced ca2+ release and then ctx added, an immediate a ... | 1993 | 8446962 |
| acetylcholine receptor binding characteristics of snake and cone snail venom postsynaptic neurotoxins: further studies with a non-radioactive assay. | the binding of postsynaptic neurotoxins from snake and marine cone snail (conus sp.) venoms to nicotinic acetylcholine receptor (achr) was investigated with an elisa-based, non-radioactive assay. three snake postsynaptic toxins from the long-chain group (naja naja kaouthia cobratoxin, naja oxiana neurotoxin i, bungarus multicinctus alpha-bungarotoxin) and short-chain group (naja naja atra cobrotoxin, naja oxiana neurotoxin ii, and laticauda semifasciata erabutoxin b) were studied. both types of ... | 1993 | 8212028 |
| effects of systemic complement activation on renal circulation of rats. | in a variety of immunopathological diseases activation of the complement cascade occurs either systemically or localized in the kidney. to elucidate the functional impact of complement activation upon the renal microcirculation, we administered cobra venom factor of naja naja kaouthia (cvf) i.v. into thiobarbital anaesthetized female rats. cvf is a potent activator of the alternative pathway of complement by forming the c3-convertase cvf, bb which cannot be downregulated by the natural inhibitor ... | 1994 | 8088308 |
| a comparison of ovine and equine antivenoms. | commercial antivenoms produced in horses were compared with monospecific antivenoms raised in sheep against crotalus durissus terrificus, crotalus atrox, crotalus adamanteus, micrurus fulvius fulvius, naja naja, naja kaouthia, echis ocellatus, vipera lebetina deserti, vipera berus berus and vipera ammodytes ammodytes venom. antibodies raised by immunizing sheep with c. d. terrificus venom were more effective than their equine counterparts in preventing lethal toxicity in mice (ed50), in inhibiti ... | 1994 | 8052997 |
| experimental evaluation of ovine antisera to thai cobra (naja kaouthia) venom and its alpha-neurotoxin. | conventional treatment of naja kaouthia (thai cobra) envenoming requires large volumes (up to 600 ml) of equine antivenom, which results in a high incidence of serum reactions. the inefficiency of the antivenom is assumed to be related to the high percentage (approx. 20%) of alpha-neurotoxin, a relatively weak and highly toxic immunogen, present in the native venom. first, antibodies to n. kaouthia venom were raised in sheep, which protected mice against challenge with whole venom. second, ovine ... | 1994 | 7725333 |
| the use of the chick biventer cervicis preparation to assess the protective activity of six international reference antivenoms on the neuromuscular effects of snake venoms in vitro. | the protective activity of some antivenoms on the neuromuscular activity in vitro of six snake venoms was established in order to test the feasibility of using a simple isolated nerve-muscle preparation to compare different antivenoms. six venoms designated as international reference venoms by the world health organization (who) were used: echis carinatus (iran), echis carinatus (mali), naja naja kaouthia, notechis scutatus, trimeresurus flavoviridis, and vipera russelli (thailand). the chick bi ... | 1994 | 8016849 |
| screening of snake venoms for neurotoxic and myotoxic effects using simple in vitro preparations from rodents and chicks. | eight snake venoms designated by the who as international reference venoms, and one additional venom were assessed for neurotoxic and myotoxic effects in vitro using the chick biventer cervicis and the rat and mouse phrenic nerve-diaphragm preparations. the objective was to determine whether any of the preparations could be used to detect evidence of neurotoxic or myotoxic activity prior to a more detailed examination. bungarus multicinctus venom at concentrations above 1 microgram ml-1 selectiv ... | 1994 | 8016848 |
| characterization of monoclonal antibodies against naja naja oxiana neurotoxin i. | seven monoclonal antibodies (mabs) were developed against neurotoxin i (nt-1), a protein from central asian cobra (naja naja oxiana) venom which binds specifically to nicotinic acetylcholine receptor (achr). all of the mabs cross-reacted with another long-chain post-synaptic neurotoxin, bungarus multicinctus alpha-bungarotoxin (alpha-bt), but not naja naja kaouthia alpha-cobratoxin, in an enzyme-linked immunosorbent assay (e.l.i.s.a.). short-chain post-synaptic neurotoxins like naja naja atra co ... | 1994 | 7945236 |
| the two subunits of a phospholipase a2 inhibitor from the plasma of thailand cobra having structural similarity to urokinase-type plasminogen activator receptor and ly-6 related proteins. | amino acid sequences of the two subunits (31-kda and 25-kda subunits) of a phospholipase a2 (pla2) inhibitory protein, purified from the blood plasma of thailand cobra naja naja kaouthia, were determined by alignment of peptides obtained by lysyl endopeptidase, staphylococcal v8 protease and endoproteinase asp-n digestions. the respective subunits were composed of 188 and 185 amino acid residues, and the former contained one asparagine-linked sugar chain at the position 157. there was 29% identi ... | 1994 | 7980598 |
| isolation and characterization of a phospholipase a2 inhibitor from the blood plasma of the thailand cobra naja naja kaouthia. | a phospholipase a2 (pla2) inhibitory protein was purified from the blood plasma of the thailand cobra naja naja kaouthia by sequential chromatography on sephadex g-200, deae affi-gel blue, and protein-pak g-butyl columns. the purified inhibitor was a glycoprotein with an apparent molecular mass of about 90 kda and contained 25- and 31-kda subunits with a molar ratio of 1:2. the 31-kda subunit contained a glycosidic chain and the molecular mass was reduced to 28 kda by n-glycosidase f treatment. ... | 1994 | 8179612 |
| development of alpha-neurotoxin antibodies in patients envenomed by the monocellate thai cobra (naja kaouthia). | serum samples from 50 patients envenomed by the thai cobra (naja kaouthia) were tested by enzyme immune assay for the presence of antibodies against the principal neurotoxin. samples were taken between 1 month and 19 years after the bite. only 16% (8/50) of the samples were positive for antibodies against neurotoxin, while 76% (38/50) were positive for antibodies against whole venom. there was no clear correlation between the presence of antibodies against neurotoxin and clinical features. | 1994 | 7725334 |
| presynaptically acting snake venom phospholipase a2 enzymes attack unique substrates. | synaptosomes were incubated with bovine serum albumin (bsa) to examine whether the presynaptic action of snake venom phospholipase a2 (pla2) toxins is due either to the release of fatty acids resistant to extraction by bsa or to the liberation of a specific fatty acid type. in the presence of bsa (0.5% or 1.0%) two pla2 enzymes from naja naja atra and naja naja kaouthia snake venoms that do not have a predominant presynaptic action at the neuromuscular junction (ps-) did not stimulate acetylchol ... | 1995 | 8866614 |
| bovine serum albumin does not completely block synaptosomal cholinergic activities of presynaptically acting snake venom phospholipase a2 enzymes. | bovine serum albumin (bsa), which binds fatty acids, was used to test the contribution of free fatty acid to the presynaptic toxicity of phospholipase a2 (pla2) enzymes. the effects of bsa on inhibition of [14c]choline uptake and stimulation of [14c]acetylcholine (ach) release in synaptosomes by pla2 enzymes that do not have a predominant presynaptic action at the neuromuscular junction (ps-) were compared with those on the cholinergic actions of pla2 enzymes that do have a predominant presynapt ... | 1995 | 8533139 |
| the use of fluoresceinphosphatidylethanolamine (fpe) as a real-time probe for peptide-membrane interactions. | the characterization of fluoresceinphosphatidylethanolamine (fpe) as a real-time indicator of the electrostatic nature of a membrane surface is described. the conditions appropriate for the labelling of membranes and the implementation of fpe as a tool to monitor the interactions of various peptides with model membranes are outlined. it is shown that of the membrane-active peptides studied, naja naja kaouthia cardiotoxin and pyrularia thionin bind to certain model membranes without insertion. wh ... | 1995 | 7795709 |
| evidence of the coevolution of a snake toxin and its endogenous antitoxin cloning, sequence and expression of a serum albumin cdna of the chinese cobra. | a full-length cdna of the serum albumin (csa) of the cobra (naja naja kaouthia) was cloned from a lambda gt 11 library. it encodes a mature protein of 614 amino-acid residues homologous to the precursor of mammalian serum albumins. the 1 degree and 2 degrees structures of the csa resemble those of the human variety. the putative toxin binding sites are mainly located in the subdomains iia and iiia. the relation between structural homology and function of the serum albumins (sa) is discussed. an ... | 1995 | 8561913 |
| no role for enzymatic activity or dantrolene-sensitive ca2+ stores in the muscular effects of bothropstoxin, a lys49 phospholipase a2 myotoxin. | the role of low levels of phospholipase a2 (pla2) activity and intracellular ca2+ stores in the pharmacological action of bothropstoxin (bthtx), a myotoxic lys49 pla2 homologue isolated from the venom of bothrops jararacussu, was investigated. we examined the muscular effects of bthtx in the mouse diaphragm and its pla2 activity in radiolabeled human and rat primary cultures of skeletal muscle. although it is a lys49 pla2 homologue, bthtx had a low, but easily detectable, level of enzymatic acti ... | 1995 | 8744987 |
| neostigmine for the treatment of neurotoxicity following envenomation by the asiatic cobra. | envenomation by the monocellate cobra (naja kaouthia) is usually manifested clinically as neurotoxicity and local tissue necrosis. treatment often requires administration of large quantities of antivenin, resulting in a high incidence of serum reactions. in cases where antivenin administration may be delayed for several hours or administration is contraindicated, the use of the anticholinesterase drug neostigmine may temporarily reverse the potentially lethal neurological effects of the venom. d ... | 1996 | 8669746 |
| cross-neutralization of thai cobra (naja kaouthia) and spitting cobra (naja siamensis) venoms by thai cobra antivenom. | the neutralizing capacity of antivenom prepared against thai cobra (naja kaouthia) venom was compared in mice using the homologous venom and that of spitting cobra (naja siamensis). the amounts of antivenoms neutralizing a dose of 4 ld50 of the test venom were determined. four antivenom preparations were used: three purified antivenoms and a crude antivenom, which were made using n. kaouthia venom only. almost the same neutralizing capacity was obtained with the purified antivenoms, whereas a sl ... | 1997 | 9428112 |
| production of highly potent horse antivenom against the thai cobra (naja kaouthia). | naja kaouthia (nk) causes the highest fatality due to snake venom poisoning in thailand. the specific antivenom produced is of low potency and in short supply. the aim of this study was to improve the antivenom potency. bentonite and complete freund's adjuvants (cfa) and various immunogens were compared. six groups of three to five horses were immunized as follows: group 1, nk venom adsorbed on bentonite; group 2, nk venom in cfa; group 3, nk venom in cfa in multi-emulsion formulation; group 4, ... | 1997 | 9330463 |
| quantitative comparison on the refinement of horse antivenom by salt fractionation and ion-exchange chromatography. | a quantitative comparison was made on the fractionation of pepsin-digested horse antivenoms by ammonium sulfate (as) fractional precipitation and ion-exchange chromatography on q-sepharose. in the precipitation process, pepsin digested horse anti-naja kaouthia serum was precipitated by 30% saturated as followed by 50% saturated as. the recovery of antibody activity [as measured by an enzyme-linked immunosorbent assay (elisa) against the cobra postsynaptic neurotoxin 3] from the 30-50% saturated ... | 1997 | 9390734 |
| purification of the nicotinic acetylcholine receptor protein by affinity chromatography using a regioselectively modified and reversibly immobilized alpha-toxin from naja nigricollis. | a new method of affinity chromatography purification of the detergent-solubilized nicotinic acetylcholine receptor protein (nachr) is presented, based on the reversible coupling of a chemically monomodified alpha-toxin from naja nigricollis to a resin. the alpha-toxin was monothiolated on the epsilon-amino group of its lysine-15 by reaction with n-succinimidly-3-(2-pyridyldithio)propionate and was covalently linked in a reversible manner to a thiopropyl-activated agarose resin by thiol-disulfide ... | 1997 | 9059496 |
| an experimental study on evaluation of chemical antagonists induced snake venom neutralization. | the present investigation explored the snake venom neutralizing capacity of four chemical compounds (2-hydroxy-4-methoxy benzoic acid, anisic acid, salicylic acid and aspirin) in experimental animals. the venoms of common indian snakes viper russellii, echis carinatus, naja kaouthia and ophiophagus hannah were taken to evaluate the lethal, haemorrhagic and defibrinogenation action neutralization. lethal action of venom was maximum neutralized with 2-hydroxy-4-methoxy benzoic acid and anisic acid ... | 1998 | 9599954 |
| preparations of toxic components from naja kaouthia venom by selective heat denaturation. | a simple procedure to prepare the toxic components from naja kaouthia venom for use as immunogens has been studied. the aim was to produce serum rich in antitoxins. by heating the venom (1-6 mg/ml) at 100 degrees c for 10 min at ph 5.0, at least 10 proteins with mw greater than 25,000 daltons were precipitated and removed. the toxic components, i.e., postsynaptic toxins, direct lytic factor (dlf), and phospholipase a2 were relatively stable to this treatment; however, their activities were progr ... | 1998 | 9689601 |
| venomous snakebite in thailand. i: medically important snakes. | thailand has an abundance of venomous snakes. among the neurotoxic family elapidae, there are three species of the genus naja (cobras), three of the genus bungarus (kraits), and the king cobra of the genus ophiophagus. other elapidae snakes in thailand include sea snakes and asian coral snakes of the genus calliophis. they have potent venoms but rarely bite humans. tissue and hemotoxic snakes are represented by family viperidae, subfamilies viperinae and crotalinae. they remain an occupational h ... | 1998 | 9597848 |
| elucidation of a new biological function of an old protein: unique structure of the cobra serum albumin controls its specific toxin binding activity. | although few proteins have been studies as thoroughly as serum albumin, a new biological property of this evolutionary ancient protein was recently discovered: the ability of cobra serum albumin (csa) to specifically sequester lethal endogenous toxins. a study of the structural basis of this property is reported in this contribution. two independent approaches were used to alter the structure of the csa at defined positions: directed mutagenesis and limited proteolysis. the conserved pattern of ... | 1998 | 9608676 |
| purification and characterization of kaouthiagin, a von willebrand factor-binding and -cleaving metalloproteinase from naha kaouthia cobra venom. | a von willebrand factor (vwf)-binding and -cleaving metalloproteinase, termed "kaouthiagin", was purified from the venom of cobra snake naja kaouthia. kaouthiagin is a monomer with a molecular mass of about 46 kda and 51 kda under non-reducing and reducing conditions, respectively, and the n-terminal amino acid sequence is homologous to high molecular mass snake venom metalloproteinases. kaouthiagin bound to vwf in a divalent ion-independent manner, but the reduced kaouthiagin failed to interact ... | 1998 | 9759634 |
| envenomation of mice by thai cobra (naja kaouthia) venom: tolerable venom concentration and exposure time. | naja kaouthia venom appeared in circulation rapidly after intramuscular injection into mice. the venom concentration attained a maximum level with all doses examined after 20 min. the half value of the maximum level was obtained 1 min after injection when a dose of 4ld50 was used. a critical venom concentration endangering mice was assessed from venom concentration in the sera of mice envenomed with sublethal dose (ld50). a fatal condition was produced within 30 min at a venom concentration of 2 ... | 1998 | 9655643 |
| development of reversed passive latex agglutination for detection of thai cobra (naja kaouthia) venom. | a simple, rapid, and sensitive diagnostic kit for detecting thai cobra (naja kaouthia) venom was developed using latex particles sensitized with venom specific immunoglobulin. the kit is capable of detecting 25-50 ng/ml of thai cobra venom. the capability was not affected by human plasma. specificity of the kit was proven using snake venoms from vipera russelli, calloselasma rhodostoma, trimeresurus albolabris, naja siamensis, ophiophagus hannah, and bungarus fasciatus. the diagnostic kit does n ... | 1999 | 10410332 |
| variability among the sites by which curaremimetic toxins bind to torpedo acetylcholine receptor, as revealed by identification of the functional residues of alpha-cobratoxin. | alpha-cobratoxin, a long chain curaremimetic toxin from naja kaouthia venom, was produced recombinantly (ralpha-cbtx) from escherichia coli. it was indistinguishable from the snake toxin. mutations at 8 of the 29 explored toxin positions resulted in affinity decreases for torpedo receptor with deltadeltag higher than 1.1 kcal/mol. these are r33e > k49e > d27r > k23e > f29a >/= w25a > r36a >/= f65a. these positions cover a homogeneous surface of approximately 880 a(2) and mostly belong to the sec ... | 1999 | 10574958 |
| isolation and amino acid sequence of a phospholipase a2 inhibitor from the blood plasma of the sea krait, laticauda semifasciata. | a phospholipase a2 (pla2) inhibitor was purified from the blood plasma of a sea krait, laticauda semifasciata, by sequential chromatography on sephadex g-200, mono q, and phenyl sepharose columns. the purified inhibitor was found to be the same type as the pla2 inhibitors, named pligamma, that had been purified from the blood plasma of the thai cobra naja naja kaouthia [ohkura et al. (1994) biochem. biophys. res. commun. 200, 784-788] and chinese mamushi agkistrodon blomhoffii siniticus [ohkura ... | 1999 | 9990137 |
| muscarinic toxin-like proteins from cobra venom. | three new polypeptides were isolated from the venom of the thailand cobra naja kaouthia and their amino-acid sequences determined. they consist of 65-amino-acid residues and have four disulfide bridges. a comparison of the amino-acid sequences of the new polypeptides with those of snake toxins shows that two of them (mtlp-1 and mtlp-2) share a high degree of similarity (55-74% sequence identity) with muscarinic toxins from the mamba. the third polypeptide (mtlp-3) is similar to muscarinic toxins ... | 2000 | 11082188 |
| regional and accelerated molecular evolution in group i snake venom gland phospholipase a2 isozymes. | in accordance with detection of a few phospholipase a2 (pla2) isozyme genes by southern blot analysis, only two cdnas, named nnkpla-i , and nnkpla-ii, encoding group i pla2s, nnkpla-i and nnkpla-ii, respectively, were isolated from the venom gland cdna library of elapinae naja naja kaouthia of malaysia. nnkpla-i and nnkpla-ii showed four amino acid substitutions, all of which were brought about by single nucleotide substitution. no existence of clones encoding cm-ii and cm-iii, pla2 isozymes whi ... | 2000 | 10669032 |
| first tryptophan-containing weak neurotoxin from cobra venom. | with the purpose of studying structure-function relationships among weak neurotoxins (called so because of their low toxicity), we have isolated a toxin (wtx) from the venom of cobra naja kaouthia using a combination of gel-filtration and ion-exchange chromatography. the amino acid sequence of the isolated toxin was determined by means of edman degradation and maldi mass spectrometry, the primary structure obtained being confirmed by 1h-nmr in the course of spatial structure analysis. the wtx se ... | 2001 | 11223079 |
| decreased levels of nerve growth factor in organs of mice as a consequence of sub-lethal injection of cobra venom. | nerve growth factor (ngf) is endogenously present in salivary glands of mice and sex organs of various animals. this research reports the presence of ngf in almost all major organs of mice at varying concentrations. the research further reports that intramuscular injection of a sub-lethal dose of naja kaouthia venom lowered the levels of ngf in the organs of mice. adult balb/c male mice were injected with a half lethal dose of cobra venom. the mice were sacrificed for organs at 2, 8, and 24 hour ... | 2001 | 11695817 |
| three cases of severe neurotoxicity after cobra bite (naja kaouthia). | 2001 | 11400547 | |
| preliminary crystallographic analysis of phospholipase a(2) from naja naja kaouthia lesson venom. | an acidic phospholipase a(2) isolated from the venom of naja naja kaouthia lesson in guangxi exhibits anticoagulative and hemolytic activities. in this work, the enzyme was crystallized by the method of hanging drop vapor diffusion. two crystal forms were obtained and characterized by x-ray diffraction. one of them belonged to space group p 4 ( 3 ) 2 ( 1 )2 or p4(1)2(1)2 with unit cell parameters a b 8.797 nm, c 10.831 nm and there were three molecules per asymmetric unit the other belonged to s ... | 2001 | 12040404 |
| effectiveness of thai cobra (naja kaouthia) antivenom against sea snake (lapemis hardwickii) venom: verification by affinity purified f(ab')2 fragments. | commercial thai cobra (naja kaouthia) antivenom was found to be effective in neutralizing sea snake (lapemis hardwickii) venom. neurotoxin specific f(ab')2 fragments obtained from the antivenom by chromatography using thai cobra neurotoxin or sea snake venom affinity columns were able to neutralize both venoms. | 2001 | 11491464 |
| a highly active anticomplement factor from the venom of naja kaouthia. | a highly active anticomplement factor (cobra venom factor) from the venom of naja kaouthia in south yunnan, china was isolated by sequential column chromatography (sp-sephadex-c-25, q sepharose hp and sephadex g-150). it displays strong anticomplement activities in vitro and in vivo, and has anticomplement activity of 1 515 u per mg. the purified anticomplement factor was homogeneous on sds-page with a molecular weight of 149 kd. it is composed of three polypeptide chains which are connected by ... | 2001 | 12040387 |
| "weak toxin" from naja kaouthia is a nontoxic antagonist of alpha 7 and muscle-type nicotinic acetylcholine receptors. | a novel "weak toxin" (wtx) from naja kaouthia snake venom competes with [(125)i]alpha-bungarotoxin for binding to the membrane-bound torpedo californica acetylcholine receptor (achr), with an ic(50) of approximately 2.2 microm. in this respect, it is approximately 300 times less potent than neurotoxin ii from naja oxiana and alpha-cobratoxin from n. kaouthia, representing short-type and long-type alpha-neurotoxins, respectively. wtx and alpha-cobratoxin displaced [(125)i]alpha-bungarotoxin from ... | 2001 | 11279130 |
| development of a polymerase chain reaction to distinguish monocellate cobra (naja khouthia) bites from other common thai snake species, using both venom extracts and bite-site swabs. | a pcr technique was used in this study to identify and distinguish monocellate cobra snake bites using snake venoms and swab specimens from snake bite-sites in mice from bites by other common thai snakes. the sequences of nucleotide primers were selected for the cobrotoxin-encoding gene from the chinese cobra (naja atra) since the sequences of monocellate cobra (naja kaouthia) venom are still unknown. however, the 113-bp fragment of cdna of the cobrotoxin-encoding gene was detected in the monoce ... | 2001 | 11223099 |
| binding to and hemolysis of human erythrocytes by pyrularia thionin and naja naja kaouthia cardiotoxin: inhibition by prothrombin. | pyrularia thionin and snake venom cardiotoxin are strongly basic proteins which bind to and induce hemolysis of erythrocytes, cause depolarization of muscle cells, and influence the order and properties of phospholipids in cellular membranes. earlier studies showed a competition between the thionin and cardiotoxin for a common binding site on erythrocytes, and the present study extends these studies to show a similar competition between prothrombin and both basic proteins. the competition betwee ... | 2001 | 11491465 |
| production of potent polyvalent antivenom against three elapid venoms using a low dose, low volume, multi-site immunization protocol. | the purpose of this study was to prepare a potent polyvalent antivenom against three elapids namely, the thai cobra (naja kaouthia, nk), the king cobra (ophiophagus hannah, oh) and the banded krait (bungarus fasciatus, bf). two groups of horses were immunized. group 1, comprising five horses, was immunized twice with a mixture of postsynaptic neurotoxins followed by an additional six immunizations with a mixture of crude venoms of the three elapids. group 2, comprising four horses, was immunized ... | 2001 | 11478956 |
| [the weak neurotoxin from naja kaouthia cobra venom decreases the arterial blood pressure in rats]. | the weak neurotoxin from the naja kaouthia cobra venom was found to reduce, under the intravenous administration to rats, the arterial blood pressure and increase the heart rate. | 2001 | 11443946 |
| two forms of nerve growth factor from cobra venom prevent the death of pc12 cells in serum-free medium. | nerve growth factor (ngf) from the venom of cobra naja kaouthia is highly homologous to mouse ngf. however, the differences between these two factors include the sequence regions determining the specificity of ngf interaction with trk a or p75 receptors. to test if these variations can bring about dissimilarity in biological activity between these two ngfs, we have studied the effect of cobra factor on the survival of the primed pc12 cells after serum withdrawal. it was found that in a serum-fre ... | 2001 | 11288731 |
| complete amino acid sequence of kaouthiagin, a novel cobra venom metalloproteinase with two disintegrin-like sequences. | the primary structure of kaouthiagin, a metalloproteinase from the venom of the cobra snake naja kaouthia which specifically cleaves human von willebrand factor (vwf), was determined by amino acid sequencing. kaouthiagin is composed of 401 amino acid residues and one asn-linked sugar chain. the sequence is highly similar to those of high-molecular mass snake venom metalloproteinases from viperid and crotalid venoms comprised of metalloproteinase, disintegrin-like, and cys-rich domains. the metal ... | 2001 | 11284707 |
| inhibition of human platelet aggregation by l-amino acid oxidase purified from naja naja kaouthia venom. | l-amino acid oxidase (lao) widely exists in snake venoms. purification of lao from the naja naja kaouthia (monocellate cobra) venom has been reported (tan and swaminathan, 1992), but its structural characterization and physiological function remained to be determined. the function of snake venom laos in hemostasis, especially their effect on platelet aggregation, has been controversial. we determined the n-terminal amino acid sequence of the n. n. kaouthia lao named k-lao to be ddrrspleecfqqndye ... | 2001 | 11600144 |
| neutralisation of lethality, myotoxicity and toxic enzymes of naja kaouthia venom by mimosa pudica root extracts. | aqueous and alcoholic extracts of dried roots of mimosa pudica were tested for their inhibitory activity on lethality, myotoxicity and toxic enzymes of naja kaouthia venom. the aqueous extract, particularly the normal water extract, displayed a significant inhibitory effect on the lethality, myotoxicity and tested enzyme activities of venom compared with alcoholic extracts. the present finding suggests that aqueous extracts of m. pudica root possess compound(s), which inhibit the activity of cob ... | 2001 | 11282444 |
| comparative study of three short-chain neurotoxins from the venom of naja kaouthia (yunnan, china). | three short-chain neurotoxins named nt-1, nt-ii, and nt-iii were purified from the venom of naja kaouthia, a snake distributed throughout the south of yunnan province, china, by a series of chromatographic steps, including an fplc resource s column. their molecular weights, determined by matrix-assisted laser desorption ionization time-of-flight (maldi-tof) ms, were 6952.19 da, 6854.92 da, and 6828.80 da, respectively. nt-i consisted of 62 amino acid residues, and the other two consisted of 61 a ... | 2002 | 12182542 |
| changes in body temperature pattern in vertebrates do not influence the codon usages of alpha-globin genes. | codon usages are known to vary among vertebrates chiefly due to variations in isochore structure. under the assumption that marked differences exist in isochore structure between warm-blooded and cold-blooded animals, the variations among vertebrates were previously attributed to an adaptation to homeothermy. however, based on data from a turtle species and a crocodile (archosauromorpha), it was recently proposed that the common ancestors of mammals, birds and extent reptiles already had the "wa ... | 2002 | 12207041 |
| structure-function relationship of three neurotoxins from the venom of naja kaouthia: a comparison between the nmr-derived structure of nt2 with its homologues, nt1 and nt3. | three homologous short-chain neurotoxins, named nt1, nt2 and nt3, were purified from the venom of naja kaouthia. nt1 has an identical amino acid sequence to cobrotoxin from naja naja atra [biochemistry 32 (1993) 2131]. nt3 shares the same sequence with cobrotoxin b [j. biochem. (tokyo) 122 (1997) 1252], whereas nt2 is a novel 61-residue neurotoxin. tests of their physiological functions indicate that nt1 shows a greater inhibition of muscle contraction induced by electrical stimulation of the ne ... | 2002 | 11904231 |
| post-ovipositional development of the monocled cobra, naja kaouthia (serpentes: elapidae). | external morphological development between oviposition and hatching of the monocled cobra, naja kaouthia, is described. ten developmental stages are diagnosed according to nine features. these include fusion of the body wall musculature along the ventral midline, appearance of the endolymphatic ducts, formation of the eyelid, and the appearance of scales on the head and body. additional observations of the developing skull are made at four of these ten stages, based on cleared and stained heads. | 2002 | 16351869 |
| restoration of nerve growth factor in organs of mice injected with cobra venom followed by specific treatment and reversal period. | research from this laboratory reported the decreased levels of endogenously present nerve growth factor (ngf) in organs of mice as a consequence of sub-lethal injection of naja kaouthia venom. this research reports that the decreased levels of ngf in organs of mice were prevented by (1) specific treatment and (2) restored to normal by a prolonged period. adult female balb/c mice were injected intramuscularly (im) with a sub-lethal dose of cobra venom. the injected mice were divided into five gro ... | 2002 | 12009116 |
| biochemical composition, lethality and pathophysiology of venom from two cobras-- naja naja and n. kaouthia. | the cobras naja naja and n. kaouthia are abundant in eastern and north-eastern india, accounting for maximum snakebite deaths. here we report on variation in the composition of naja kaouthia and n. naja venom from eastern india on corresponding differences in the severity of pathogenesis. these two venoms differ in chromatographic elution profile through sephadex g-50 and enzyme activity, protein and carbohydrate contents associated with each fraction. the presence of greater amounts of basic ph ... | 2002 | 11818235 |
| a novel short neurotoxin, cobrotoxin c, from monocellate cobra (naja kaouthia) venom: isolation and purification, primary and secondary structure determination, and tertiary structure modeling. | a novel short neurotoxin, cobrotoxin c (cbt c) was isolated from the venom of monocellate cobra (naja kaouthia) using a combination of ion-exchange chromatography and fplc. its primary structure was determined by edman degradation. cbt c is composed of 61 amino acid residues. it differs from cobrotoxin b (cbt b) by only two amino acid substitutions, thr/ala11 and arg/thr56, which are not located on the functionally important regions by sequence similarity. however, the ld50 is 0.08 mg/g to mice, ... | 2002 | 12039691 |
| crystal structures of an acidic phospholipase a(2) from the venom of naja kaouthia. | a phospholipase a(2) purified from the venom of naja kaouthia (guangxi cobra) exhibits anticoagulant activities. the structures of two crystal forms were determined by x-ray crystallography at 2.8a resolution with the naja naja (india cobra) pla(2) as an initial model. the enzyme exhibits a trimer structure, which is similar to that of india cobra pla(2). this reinforces the physiological relevance of the oligomer. the trimer has a wide cavity, which allows the substrate to enter and interact wi ... | 2002 | 12076645 |
| purification and characterization of an anticoagulant phospholipase a(2) from indian monocled cobra (naja kaouthia) venom. | an anticoagulant, non-toxic phospholipase a(2) was isolated from the venom of indian monocled cobra (naja kaouthia) by a combination of ion-exchange chromatography on cm-sephadex c-50 and gel filtration on sephadex g-50. this purified protein named nk-pla(2)-i, had a subunit molecular mass of 13.6 kda and migrated as a dimer under non-reduced condition in sds-page. nk-pla(2)-i was a highly thermostable protein requiring basic ph optima for its catalytic activity and showed preferential hydrolysi ... | 2003 | 12467665 |
| alpha-neurotoxins of naja atra and naja kaouthia snakes in different regions. | recent studies have shown that there are geographic variation of alpha-neurotoxins in naja kaouthia, but the cause is not clear yet. in this work, venoms were collected from adult naja atra in zhejiang province and naja kaouthia in yunnan province, well identified by morphological characters and cytochrome b gene analysis in summer season to avoid age and seasonal variation in the venom composition. then alpha-neurotoxins were purified and cloned from these two kinds of snakes. three alpha-neuro ... | 2003 | 12897961 |
| direct cloning of a target gene from a pool of homologous sequences: complete cdna sequence of a weak neurotoxin from cobra naja kaouthia. | selective cloning of the cdna coding for a weak neurotoxin (wtx) from cobra n. kaouthia including the 5'- and 3'-non-translated regions (ntr) is described. the known amino acid sequence of wtx was used together with the nucleotide sequence of a weak neurotoxin nnam2 from cobra naja atra, to design wtx-specific primers for direct amplification of an internal wtx cdna fragment by rt- pcr. the sequence of the complete wtx cdna was determined in sequencing runs on internal pcr products, cloned 3'- a ... | 2003 | 12716062 |
| neurotoxic and myotoxic actions of naja naja kaouthia venom on skeletal muscle in vitro. | the neuromuscular and skeletal muscle actions of naja naja kaouthia snake venom were studied in mammalian (rat left hemidiaphragm) and avian (chick biventer cervicis) nerve-muscle preparations. the venom (5 and 10 micro g/ml) produced neuromuscular blockade (85% in 36.8+/-2.0min, mean+/-sem, n=5, and 18+/-0.6min, n=3, p<0.01, respectively) in the rat preparation. that the phospholipase a(2) (pla(2)) activity of the venom is involved in this effect was evaluated by inhibiting this enzyme with p-b ... | 2003 | 12727270 |
| prolonged cardiac xenograft survival in guinea pig-to-rat model by a highly active cobra venom factor. | a highly active cobra venom factor (cvf) was isolated from the venom of naja kaouthia by sequential column chromatography. it displays strong anticomplementary activity, and has 1515 u of anticomplementary activity per mg protein. a single dose of 0.1 mg/kg cvf given i.v. to rats completely abrogated complement activity for nearly 5 days. given 0.02 mg/kg of cvf, the complement activity of rats was reduced by more than 96.5% in 6 h. in guinea pig-to-rat heart transplant model, rats treated with ... | 2003 | 14559076 |
| hyaluronidase inhibitors (sodium cromoglycate and sodium auro-thiomalate) reduce the local tissue damage and prolong the survival time of mice injected with naja kaouthia and calloselasma rhodostoma venoms. | experiments have been carried out to find potent inhibitors of hyaluronidases of naja kaouthia (nk) and calloselasma rhodostoma (cr) venoms with the aim of reducing local tissue damage and systemic toxicities caused by the venoms. seven drugs/chemicals known to inhibit hyaluronidases were tested for their activity on venom enzymes. these were: sodium cromoglycate (sc), sodium aurothiomalate (sat), apigenin, kaemferol, phenylbutazone, oxyphenbutazone and fenoprofen. the results showed that sc or ... | 2003 | 14602119 |
| snake venom neutralization by indian medicinal plants (vitex negundo and emblica officinalis) root extracts. | the methanolic root extracts of vitex negundo linn. and emblica officinalis gaertn. were explored for the first time for antisnake venom activity. the plant (v. negundo and e. officinalis) extracts significantly antagonized the vipera russellii and naja kaouthia venom induced lethal activity both in in vitro and in vivo studies. v. russellii venom-induced haemorrhage, coagulant, defibrinogenating and inflammatory activity was significantly neutralized by both plant extracts. no precipitating ban ... | 2003 | 12686445 |
| comparative study of structure and activity of cytotoxins from venom of the cobras naja oxiana, naja kaouthia, and naja haje. | cytotoxins are positively charged polypeptides that constitute about 60% of all proteins in cobra venom; they have a wide spectrum of biological activities. by cd spectroscopy, cytotoxins ct1 and ct2 naja oxiana, ct3 naja kaouthia, and ct1 and ct2 naja haje were shown to have similar secondary structure in an aqueous environment, with dominating beta-sheet structure, and to vary in the twisting angle of the beta-sheet and the conformation of disulfide groups. using dodecylphosphocholine micelles ... | 2004 | 15527416 |
| improved suppression of circulating complement does not block acute vascular rejection of pig-to-rhesus monkey cardiac transplants. | at present, acute vascular rejection (avr) remains a primary obstacle inhibiting long-term graft survival in the pig-to-non-human primate transplant model. the present study was undertaken to determine whether repetitive injection of low dose yunnan-cobra venom factor (y-cvf), a potent complement inhibitor derived from the venom of naja kaouthia can completely abrogate hemolytic complement activity and subsequently improve the results in a pig-to-rhesus monkey heterotopic heart transplant model. ... | 2004 | 14962274 |
| the first representative of glycosylated three-fingered toxins. cytotoxin from the naja kaouthia cobra venom. | there are different glycosylated proteins in snake venoms, but no glycosylated representatives of a large family of three-fingered toxins have previously been detected. a new glycoprotein was isolated from the venom of the thai cobra naja kaouthia. maldi ms of the glycoprotein contained an array of peaks in the range from approximately 8900 to approximately 9400 da indicating its microheterogeneity. carbohydrate analysis showed the presence of mannose, galactose, n-acetylglucosamine, fucose and ... | 2004 | 15128311 |
| optical immunoassay for snake venom detection. | a sensitive and specific optical immunoassay (oia) has been developed for snake venom detection. the assay is based on the principle of detection of physical changes in thickness of molecular thin film resulting from specific binding events on an optical silicon chip (silas-i, thermobiostar, colorado, usa). the reflection of white light through the thin film results in destructive interference of a particular wavelength of the light from gold to purple-blue depending on the thickness of the thin ... | 2004 | 15046761 |
| envenoming by chinese krait (bungarus multicinctus) and banded krait (b. fasciatus) in myanmar. | a retrospective study of 8 cases of envenoming by chinese krait (bungarus multicinctus) and one banded krait (b. fasciatus) in southern myanmar is reported. chinese krait bite produced minimal local reactions, except in one person bitten on the lip which resulted in local swelling. onset of neurotoxic symptoms occurred 2.5-6 h after the bite, and the interval between bite and death ranged from 12-30 h. three deaths were due to respiratory failure. four mildly envenomed cases recovered spontaneou ... | 2004 | 9509180 |
| antisnake venom activity of ethanolic seed extract of strychnos nux vomica linn. | the whole seed extract of s. nux vomica (in low doses) effectively neutralized daboia russelii venom induced lethal, haemorrhage, defibrinogenating, pla2 enzyme activity and naja kaouthia venom induced lethal, cardiotoxic, neurotoxic, pla2 enzyme activity. the seed extract potentiated polyvalent snake venom antiserum action in experimental animals. an active compound (snvnf) was isolated and purified by thin layer chromatography and silica gel column chromatography, which effectively antagonised ... | 2004 | 15233470 |