| 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 |
| 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 |
| 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 |
| 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 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| "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 |
| 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 |
| 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 |
| 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 |
| [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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| weak neurotoxin from naja kaouthia cobra venom affects haemodynamic regulation by acting on acetylcholine receptors. | recent in vitro studies of weak neurotoxins from snake venoms have demonstrated their ability to interact with both muscle-type and neuronal alpha7 nicotinic acetylcholine receptors (nachr). however, the biological activity in vivo of weak neurotoxins remains largely unknown. we have studied the influence of weak neurotoxin (wtx) from the venom of cobra naja kaouthia on arterial blood pressure (bp) and heart rate (hr) in rats and mice. it was found that intravenous injection of wtx induced a dos ... | 2005 | 15581687 |
| immunochemical and biochemical comparisons of equine monovalent and polyvalent snake antivenoms. | although the merit of polyvalent antivenoms is well-recognized, there is still doubt in some medical circles as to the relative efficacy and the propensity to cause adverse reactions of polyvalent (pav) as compared to monovalent (mav) antivenoms. immunochemical and biochemical comparisons of equine polyvalent and monovalent antivenoms prepared under the same immunization protocols were therefore made. these antivenoms were prepared against naja kaouthia (nk), ophiophagus hannah (oh) and bungarus ... | 2005 | 15683876 |
| inhibition of naja kaouthia venom activities by plant polyphenols. | plant polyphenols from the aqueous extracts of pentace burmanica, pithecellobium dulce, areca catechu and quercus infectoria were tested for their inhibitory activities against naja kaouthia (nk) venom by in vitro neutralization method. the first three extracts could completely inhibit the lethality of the venom at 4 ld50 concentration and the venom necrotizing activity at the minimum necrotizing dose while also inhibited up to 90% of the acetylcholinesterase activity of nk venom at much lower t ... | 2005 | 15740891 |
| protective immunity against alpha-cobratoxin following a single administration of a genetic vaccine encoding a non-toxic cobratoxin variant. | venomous snakebites result in almost 125,000 deaths per year worldwide. we present a new paradigm for the development of vaccines to protect against snakebite, using knowledge of the structure and action of specific toxins combined with a gene-based strategy to deliver a toxin gene modified to render it non-toxic while maintaining its three-dimensional structure and hence its ability to function as an immunogen. as a model for this approach, we developed a genetic vaccine to protect against alph ... | 2005 | 15812224 |
| cancer cell injury by cytotoxins from cobra venom is mediated through lysosomal damage. | cytotoxins from cobra venom are known to manifest cytotoxicity in various cell types. it is widely accepted that the plasma membrane is a target of cytotoxins, but the mechanism of their action remains obscure. using the confocal spectral imaging technique, we show for the first time that cytotoxins from cobra venom penetrate readily into living cancer cells and accumulate markedly in lysosomes. cytotoxins ct1 and ct2 from naja oxiana, ct3 from naja kaouthia and ct1 from naja haje are demonstrat ... | 2005 | 15847607 |
| a study of thai cobra (naja kaouthia) bites in thailand. | this study evaluated factors affecting the severity of bite site necrosis and systemic symptoms resulting from envenomation among patients bitten by thai cobras (naja kaouthia) in thailand. we studied 45 victims prospectively. an additional 40 medical records were obtained for a retrospective study. collected data included gender of the victims, anatomic locations of bites, where attacks took place, and predisposing factors and how they might have affected the clinical course. most patients were ... | 2005 | 15916306 |
| polyclonal antibodies against native weak toxin naja kaouthia discriminate native weak toxins and some other three-fingered toxins against their denaturated forms. | polyclonal antibodies obtained by immunization of rabbits with native form of weak toxin (wtx) from cobra naja kaouthia venom efficiently interacted with wtx and a weak toxin from naja oxiana venom, but not so with their denaturated forms. these antibodies could also bind with lower affinity other groups of three-fingered toxins: long-chain alpha-neurotoxins, muscarinic toxins and cytotoxins, but practically did not bind short-chain alpha-neurotoxins. the efficiency of toxin-antibody interaction ... | 2005 | 15925395 |
| naja melanoleuca cobra venom contains two forms of complement-depleting factor (cvf). | two forms of complement-depleting cobra venom factor (cvfm1 and cvfm2), possessing molecular masses of 142.6 kda (cvfm1) and 143.1 kda (cvfm2), according to maldi mass-spectrometry, were isolated from the naja melanoleuca cobra venom. as shown by polyacrylamide gel electrophoresis in the presence of sds, both forms similarly to factor from the naja kaouthia cobra venom (cvfk) consist of three polypeptide chains with molecular masses of about 70, 50, and 30 kda, the two large subunits being glyco ... | 2005 | 16054663 |
| daboia russellii and naja kaouthia venom neutralization by lupeol acetate isolated from the root extract of indian sarsaparilla hemidesmus indicus r.br. | the present study reports the isolation and purification of lupeol acetate from the methanolic root extract of indian medicinal plant hemidesmus indicus (l.) r.br. (family: asclepiadaceae) which could neutralize venom induced action of daboia russellii and naja kaouthia on experimental animals. lupeol acetate could significantly neutralize lethality, haemorrhage, defibrinogenation, edema, pla(2) activity induced by daboia russellii venom. it also neutralized naja kaouthia venom induced lethality ... | 2006 | 16426782 |
| influence of phospholipases a2 from snake venoms on survival and neurite outgrowth in pheochromocytoma cell line pc12. | to determine whether the ability to induce neurite outgrowth in rat pheochromocytoma cell line pc12 is characteristic of phospholipases of different types, we have studied the influence of phospholipase a(2) (pla2) from cobra naja kaouthia venom and two pla2s from viper vipera nikolskii venom on pc12 cells. phospholipases from the viper venom are heterodimers in which only one of the subunits is enzymatically active, while pla2 from the cobra venom is a monomer. it was found that all three pla2s ... | 2006 | 16827660 |
| correlation between the phospholipids domains of the target cell membrane and the extent of naja kaouthia pla(2)-induced membrane damage: evidence of distinct catalytic and cytotoxic sites in pla(2) molecules. | two phospholipase a(2) (pla(2)) enzymes (nk-pla(2)-a and nk-pla(2)-b) were purified from the venom of the monocled cobra naja kaouthia. the molecular weights of nk-pla(2)-a and nk-pla(2)-b, as estimated by mass spectrometry, were 13,619 and 13,303 da respectively. both phospholipases were highly thermostable, had maximum catalytic activity at basic ph, and showed preferential hydrolysis of phosphatidylcholine. intravenous injection of either pla(2) up to a dose of 10 mg/kg body weight was non-to ... | 2007 | 17127009 |
| isolation, characterization and pentamerization of alpha-cobrotoxin specific single-domain antibodies from a naïve phage display library: preliminary findings for antivenom development. | conventional antivenoms to snakebite generated from the serum of immunized animals, often elicit adverse reactions and have mismatched pharmacokinetic profiles with their target toxins due to antibody/toxin size discrepancies which results in poor neutralization. furthermore, animal immunization protocols are often lengthy and have batch to batch variability. recombinant v(h)h-based antivenoms may help overcome these problems. three v(h)h fragments with specificity to alpha-cobrotoxin, a snake n ... | 2007 | 17257638 |
| venom of indian monocellate cobra and russell's viper show anticancer activity in experimental models. | indian monocellate cobra (naja kaouthia) and russell's viper (vipera russelli) are common snakes of the east indian sub-peninsula. the anticarcinogenic activities of their crude venoms were studied on carcinoma, sarcoma and leukemia models. sub-lethal doses of venoms showed cytotoxicity on ehrlich ascites carcinoma (eac) cells in vivo. the venoms increased lifespan of eac mice and strengthened the impaired host antioxidant system. sarcoma formation in mice (3-methylcholanthrene induced) after ve ... | 2007 | 17258413 |
| naja kaouthia: two cases of asiatic cobra envenomations. | envenomation from cobra bites causes major morbidity and mortality in asia and africa but rarely in the united states. we describe two patients bitten by the asiatic cobra (naja kaouthia)--both successfully treated in the emergency department. patient 1 was a 23-year-old woman bitten in the buttock by her cobra. examination demonstrated two puncture wounds. she developed cranial neuropathy, respiratory failure, and coagulopathy 10 h later, necessitating endotracheal intubation and polyvalent ant ... | 2007 | 17307627 |
| behavioural effects in mice and intoxication symptomatology of weak neurotoxin from cobra naja kaouthia. | weak neurotoxins belong to the superfamily of three-finger toxins from snake venoms. in general, weak toxins have a low toxicity and, contrary to other three-finger toxins, their molecular targets are not well characterized: in vitro tests indicate that these may be nicotinic acetylcholine receptors. here, we report the influence of intraperitoneal and intravenous injections of weak neurotoxin from naja kaouthia venom on mouse behaviour. dose-dependent suppression of orientation-exploration and ... | 2007 | 17371532 |
| proteome and immunome of the venom of the thai cobra, naja kaouthia. | the proteome of the thai cobra, naja kaouthia, venom, revealed by two-dimensional liquid chromatography/tandem mass spectrometry, was found to consist of peptides which could be matched with 61 proteins in the database. these proteins were classified into 12 groups according to the differences in their biological activities: cardiotoxins, cobra venom factors, a cysteine-rich toxin, cytotoxins, kaouthiagin, mocarhagin, muscarinic toxin-like proteins, neurotoxins, an oxoglutarate dehydrogenase, ph ... | 2007 | 17379268 |
| fractionation of snake venom metalloproteinases by metal ion affinity: a purified cobra metalloproteinase, nk, from naja kaouthia binds ni2+-agarose. | snake venom metalloproteinases represent unique probes for analyzing platelet adhesion receptors regulating hemostasis and thrombosis. snake venom metalloproteinase-disintegrins consist of a propeptide domain, a catalytic domain containing a metal ion-coordination sequence (hexxhxxgxxh), a disintegrin domain, and a cys-rich domain. here, we investigate whether metal ion-affinity chromatography may be used to fractionate venom metalloproteinases based on the metal ion-coordination motif. first, w ... | 2007 | 17822731 |
| single-bead-based immunofluorescence assay for snake venom detection. | in this communication, we reported a rapid and sensitive immunofluorescence method for the detection of snake venom by using microscale polystyrene beads as platform combined with semiconductor quantum dots (qdots) as fluorescence label. briefly, control rabbit igg or capture antibody for venom was covalently immobilized onto the microspheres (surface activated with carboxyl group, dyed with different color) to form the control or capture beads. when incubated with the testing samples, the venom ... | 2008 | 18179224 |
| evaluation of simultaneous permeation and metabolism of methyl nicotinate in human, snake, and shed snake skin. | the transdermal permeation and metabolic characteristics of methyl nicotinate (mn) in stratum corneum and split-thickness human skin and three species of shed snake and snake skin (elaphae obsoleta, naja kaouthia, and python molurus bivittatus) were evaluated. in vitro skin transport using excised skin and hydrolysis experiments using skin homogenate were carried out. the flux of mn, a metabolite, nicotinic acid (na), and the total (mn+na), as well as kinetic parameters (v(max) and k(m)) for hyd ... | 2008 | 18300102 |
| human monoclonal scfv neutralize lethal thai cobra, naja kaouthia, neurotoxin. | animal derived anti-naja. kaouthia (thai cobra) venom is used for specific treatment of the snake bitten victims. many recipients develop allergic reaction or anti-isotype response which causes serum sickness. a better therapeutic antibody is needed. in this study, long alpha-neurotoxin was purified from the n. kaouthia holovenom and verified by 2d-lc/ms-ms. the toxin was used as antigen in a phage bio-panning to select phage clones displaying human single chain variable antibody fragments (husc ... | 2009 | 19162253 |
| molecular docking studies and anti-enzymatic activities of thai mango seed kernel extract against snake venoms. | the ethanolic extract from seed kernels of thai mango (mske) (mangifera indica l. cv. 'fahlun') (anacardiaceae) and its major phenolic principle (pentagalloyl glucopyranose) exhibited dose-dependent inhibitory effects on enzymatic activities of phospholipase a(2) (pla(2)), hyaluronidase and l-amino acid oxidase (laao) of calloselasma rhodostoma (cr) and naja naja kaouthia (nk)venoms by in vitro tests. the anti-hemorrhagic and anti-dermonecrotic activities of mske against both venoms were clearly ... | 2009 | 19384272 |
| inhibitory effect of tea polyphenols on local tissue damage induced by snake venoms. | the methanolic extract of fresh tea leaves of camellia sinensis l. (theaceae) (cs) was assayed for its potential to inhibit enzymes with hydrolytic activity in naja naja kaouthia lesson (elapidae) and calloselasma rhodostoma kuhl (viperidae) venoms. these snake venom enzymes are responsible for the early effects of envenomation, such as local tissue damage and inflammation. the cs extract inhibited phospholipase a(2), proteases, hyaluronidase and l-amino acid oxidase in both venoms by in vitro n ... | 2010 | 19585481 |
| weak toxin wtx from naja kaouthia cobra venom interacts with both nicotinic and muscarinic acetylcholine receptors. | iodinated [125i] weak toxin from naja kaouthia (wtx) cobra venom was injected into mice, and organ-specific binding was monitored. relatively high levels of [125i]wtx were detected in the adrenal glands. rat adrenal membranes were therefore used for analysis of [125i]wtx-binding sites. specific [125i]wtx binding was partially inhibited by both alpha-cobratoxin, a blocker of the alpha7 and muscle-type nicotinic acetylcholine receptors (nachrs), and by atropine, an antagonist of the muscarinic ace ... | 2009 | 19682302 |
| isolation, complete amino acid sequence and characterization of a previously unreported post-synaptic neurotoxin - alphan3, from the venom of bungarus candidus. | the malayan krait (bungarus candidus) is one of the medically most important snake species in southeast asia. the venom from this snake has been shown to posses both presynaptic and post-synaptic neurotoxins. we have isolated a previously uncharacterized post-synaptic neurotoxin - alphan3 from the venom of b. candidus. isolation of the toxin was achieved in three successive chromatography steps - gel filtration on a sephadex g75 column, followed by ion exchange chromatography (mono-s strong cati ... | 2009 | 19728988 |
| virtual screening against alpha-cobratoxin. | alpha-cobratoxin (cbtx), the neurotoxin isolated from the venom of the thai cobra naja kaouthia , causes paralysis by preventing acetylcholine (ach) binding to nicotinic acetylcholine receptors (nachrs). in the current study, the region of the cbtx molecule that is directly involved in binding to nachrs is used as the target for anticobratoxin drug design. the crystal structure (1yi5) of cbtx in complex with the acetylcholine binding protein (achbp), a soluble homolog of the extracellular bindin ... | 2009 | 19734437 |
| rediocides a and g as potential antitoxins against cobra venom. | rediocides a and g, the principle components of trigonostemon reidioides (kurz) craib, which is known as lotthanong in thai, were investigated for a detoxification mechanism against naja kaouthia venom by in silico, in vitro, and in vivo methods. molecular dockings of alpha-cobratoxin with rediocides a and g were performed, and the binding energies were found to be -14.17 and -14.14 kcal/mol, respectively. rediocides bind to alpha-cobratoxin at the same location as alpha-cobratoxin binds to the ... | 2009 | 19774596 |
| anti-arthritic activity of indian monocellate cobra (naja kaouthia) venom on adjuvant induced arthritis. | the indian monocellate cobra venom (nkv) showed anti-arthritic activity over fca induced arthritis in male albino rats. nkv treatment (1/20th & 1/10th mld doses x 13 days, i.p.) showed significant restoration in paw & ankle volume, paw weight. urinary hydroxyproline, glucosamine, serum acp, alp and il-10 level were restored significantly, due to nkv treatment, as compared with arthritic rats. nkv also showed significant protection against arthritis induced oxidative damages. thus this study conf ... | 2010 | 19825384 |
| anti-necrosis potential of polyphenols against snake venoms. | polyphenols from the extracts of areca catechu l. and quercus infectoria oliv. inhibited phospholipase a(2), proteases, hyaluronidase and l-amino acid oxidase of naja naja kaouthia lesson (nk) and calloselasma rhodostoma kuhl (cr) venoms by in vitro tests. both extracts inhibited the hemorrhagic activity of cr venom and the dermonecrotic activity of nk venom by in vivo tests. the inhibitory activity of plant polyphenols against local tissue necrosis induced by snake venoms may be caused by inhib ... | 2009 | 19874222 |
| bacterial production and refolding from inclusion bodies of a "weak" toxin, a disulfide rich protein. | the gene for the "weak" toxin of naja kaouthia venom was expressed in escherichia coli. "weak" toxin is a specific inhibitor of nicotine acetylcholine receptor, but mechanisms of interaction of similar neurotoxins with receptors are still unknown. systems previously elaborated for neurotoxin ii from venom of the cobra naja oxiana were tested for bacterial production of "weak" toxin from n. kaouthia venom. constructs were designed for cytoplasmic production of n. kaouthia "weak" toxin in the form ... | 2009 | 19916927 |
| nerve growth factor inhibits metalloproteinase-disintegrins and blocks ectodomain shedding of platelet glycoprotein vi. | nerve growth factor (ngf) plays an important role in regulating mammalian neuronal/embryonic development, angiogenesis, and other physiological processes and has recently been investigated as a potential treatment for the neurodegenerative disorder, alzheimer disease. in this study, we provide evidence that human ngf may also function as a metalloproteinase inhibitor, based on studies of ngf from snake venom. originally, our aim was to isolate snake venom metalloproteinases targeting platelet re ... | 2010 | 20164177 |
| a lethal cardiotoxic-cytotoxic protein from the indian monocellate cobra (naja kaouthia) venom. | a lethal cardiotoxic-cytotoxic protein (mol. wt. 6.76 kda) has been purified from the indian monocellate cobra (naja kaouthia) venom by ion-exchange chromatography and hplc. cd spectra indicated the presence of 23% alpha helix, 19% beta sheets and 35% coil. complete amino acid sequence was determined by maldi, which showed similar homology with cardiotoxins/cytotoxins isolated from venom of other naja species. intraperitoneal ld(50) was 2.5 mg kg(-1) in balbc male mice. in vitro cardiotoxicity s ... | 2010 | 20595038 |
| non-covalent interaction of phospholipase a(2) (pla(2)) and kaouthiotoxin (ktx) from venom of naja kaouthia exhibits marked synergism to potentiate their cytotoxicity on target cells. | present study shows that non-covalent interaction of kaouthiotoxin (ktx) with their respective pohospholipase a(2) (pla(2)) from the venom of n. kaouthia displayed marked synergism to exert cytotoxicity without altering the biochemical properties of pla(2). for example, although nk-pla(2) or ktx alone did not induce appreciable hemolysis of washed human erythrocytes; however, the hemolytic potency of nk-pla(2): ktx complex was significantly higher. identically, selective lysis of virus infected ... | 2010 | 21544180 |
| snake cytotoxins bind to membranes via interactions with phosphatidylserine head groups of lipids. | the major representatives of elapidae snake venom, cytotoxins (cts), share similar three-fingered fold and exert diverse range of biological activities against various cell types. ct-induced cell death starts from the membrane recognition process, whose molecular details remain unclear. it is known, however, that the presence of anionic lipids in cell membranes is one of the important factors determining ct-membrane binding. in this work, we therefore investigated specific interactions between o ... | 2011 | 21559494 |
| efficacy evaluations of mimosa pudica tannin isolate (mpt) for its anti-ophidian properties. | aim of the study: evaluations of the anti-snake venom efficacy of mimosa pudica tannin isolate (mpt) obtained from root of the plant. materials and methods: mpt was investigated in vitro and in vivo for its efficacy against the venom of naja kaouthia snake. results: in vitro: (1) mice injected i.p. with mpt pre-incubated with naja kaouthia venom at concentrations as low as 0.625mg/ml showed 100% survival after a 24-h observation period. (2) in the proteomics study, mice injected with mpt pre-inc ... | 2011 | 21640180 |
| fibrinogenolytic toxin from indian monocled cobra (naja kaouthia) venom. | a fibrinogenolytic toxin of molecular weight 6.5 kda has been purified from the venom of indian monocled cobra (naja kaouthia) by repeated cation exchange chromatography on cm-sephadex c-50. the purified toxin did not show any phospholipase activity but was mildly hemolytic on human erythrocytes. this toxin, called lahirin, cleaved fibrinogen in a dose- and time-dependent manner. the digestion process apparently started with the a alpha chain, and gradually other lower-molecular-weight chains we ... | 2011 | 21654088 |
| inhibition of the nicotinic acetylcholine receptors by cobra venom +¦-neurotoxins: is there a perspective in lung cancer treatment? | nicotine exerts its oncogenic effects through the binding to nicotinic acetylcholine receptors (nachrs) and the activation of downstream pathways that block apoptosis and promote neo-angiogenesis. the nachrs of the +¦7 subtype are present on a wide variety of cancer cells and their inhibition by cobra venom neurotoxins has been proposed in several articles and reviews as a potential innovative lung cancer therapy. however, since part of the published results was recently retracted, we believe th ... | 2011 | 21695184 |
| cytoskeletal rearrangements in human red blood cells induced by snake venoms: light microscopy of shapes and nmr studies of membrane function. | rbcs (red blood cells) circulating through narrow blood capillaries withstand major deformation. the mechanical and chemical stresses commonly exerted on rbcs continue to attract interest for the study of membrane structure and function. snake venoms are lethal biochemical 'cocktails' that often contain haemotoxins, metalloproteinases, myotoxins, neurotoxins, phosphodiesterases, phospholipases and proteases. we have monitored the effects of 4 snake venoms (pseudechis guttatus, oxyuranus scutella ... | 2012 | 21933154 |
| comparative analysis of the venom proteome of four important malaysian snake species. | naja kaouthia, ophiophagus hannah, bungarus fasciatus and calloselasma rhodostoma are four venomous snakes indigenous to malaysia. in the present study, their proteomic profile by two-dimensional gel electrophoresis (2-de) have been separated and compared. | 2014 | 24593956 |
| humanized-single domain antibodies (vh/vhh) that bound specifically to naja kaouthia phospholipase a2 and neutralized the enzymatic activity. | naja kaouthia (monocled cobra) venom contains many isoforms of secreted phospholipase a2 (spla(2)). the pla(2) exerts several pharmacologic and toxic effects in the snake bitten subject, dependent or independent on the enzymatic activity. n. kaouthia venom appeared in two protein profiles, p3 and p5, after fractionating the venom by ion exchange column chromatography. in this study, phage clones displaying humanized-camel single domain antibodies (vh/v(h)h) that bound specifically to the p3 and ... | 2012 | 22852068 |
| 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 |
| molecular cloning and characterization of a complement-depleting factor from king cobra, ophiophagus hannah. | cobra venom factor (cvf) is an anti-complement factor existing in cobra venom. cvf proteins have been purified from the venoms of naja haje, naja siamensis, naja atra, naja kaouthia, naja naja, naja melanoleuca and austrelaps superbus, but only three full-length cdna sequences of cvf are available. in the present work, a cobra venom factor termed ovf was purified from the crude venom of ophiophagus hannah by successive gel filtration, ion-exchange and heparin affinity chromatography steps. the p ... | 2012 | 22561424 |
| isolation of a snake venom phospholipase a2 (pla2) inhibitor (aiplai) from leaves of azadirachta indica (neem): mechanism of pla2 inhibition by aiplai in vitro condition. | a compound (aiplai (azadirachta indica pla(2) inhibitor)) purified from the methanolic leaf extract of a. indica (neem) inhibits the cobra and russell's viper venoms (rvvs) phospholipase a(2) enzymes in a dose-dependent manner. inhibition of catalytic and tested pharmacological properties of cobra venom (naja naja and naja kaouthia) pla(2) enzymes by aiplai is significantly higher (p<0.05) compared to the inhibition of pla(2) enzymes of crude rvv (daboia russelli) when tested under the same cond ... | 2008 | 18466944 |
| inhibition of nicotinic acetylcholine receptors, a novel facet in the pleiotropic activities of snake venom phospholipases a2. | phospholipases a2 represent the most abundant family of snake venom proteins. they manifest an array of biological activities, which is constantly expanding. we have recently shown that a protein bitanarin, isolated from the venom of the puff adder bitis arietans and possessing high phospholipolytic activity, interacts with different types of nicotinic acetylcholine receptors and with the acetylcholine-binding protein. to check if this property is characteristic to all venom phospholipases a2, w ... | 2014 | 25522251 |
| 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 |
| 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 |