| phospholipase a2 as a probe of phospholipid distribution in erythrocyte membranes. factors influencing the apparent specificity of the reaction. | the action of snake venom phospholipases a2 in intact human erythrocytes was investigated in detail. the basis phospholipase from agkistrodon halys blomhifii was found to induce both hydrolysis of membrane phospholipids and total cell hemolysis under certain experimental conditions. the hydrolytic action of the basic enzyme was found to consist of two sequential events: (a) hydrolysis of 70% of the total cell ph osphatidylcholine without any evident hemolysis; and (b) complete hydrolysis of the ... | 1975 | 54 |
| kinetic study of the action of snake venom phospholipase a2 on human serum high density lipoprotein 3. | the hydrolysis of the phospholipids of intact human serum high density lipoprotein 3 (hdl3) by pure alpha-phospholipase a2 from crotalus adamanteus was studied by ph-stat titration. the enzyme quantitatively hydrolyzed phosphatidylcholine and phosphatidylethanolamine and left sphinogomyelin intact, yielding a stable and water-soluble modified hdl. lysophospholipids and free fatty acids, the products of hydrolysis, remained in the lipoprotein. when 1 mol of defatted bovine serum albumin/mol of su ... | 1976 | 5436 |
| vinylglycine and proparglyglycine: complementary suicide substrates for l-amino acid oxidase and d-amino acid oxidase. | proparglyglycine (2-amino-4-pentynoate) and vinylglycine (2-amino-3-butenoate) have been examined as substrates and possible inactivators of two flavo enzymes, d-amino acid oxidase from pig kidney and l-amino acid oxidase from crotalus adamanteus venom. vinylglycine is rapidly oxidized by both enzymes but only l-amino acid oxidase is inactivated under assay conditions. the loss of activity probably involves covalent modification of an active site residue rather than the flavin adenine dinucleoti ... | 1976 | 8082 |
| effect of purified phospholipases on the binding of tetrodotoxin to axon plasma membrane. | the role of phospholipids in the binding of [3h]tetrodotoxin to garfish olfactory nerve axon plasma membrane was studied by the use of purified phospholipases. treatment of the membranes with low concentrations of either phospholipase a2 (crotalus adamanteus and naja naja) or phospholipase c (bacillus cereus and clostridium perfringens) resulted in a marked reduction in tetrodotoxin binding activity. a 90% reduction in the activity occurred with about 45% hydrolysis of membrane phospholipids by ... | 1979 | 39172 |
| postitional specificity of fatty acids in pyrophosphatidic acid from cryptococcus neoformans. | pyrophosphatidic acid isolated from cryptococcus neoformans was degraded to phosphatidic acid in aqueous pyridine. the phosphatidic acid was hydrolyzed by phospholipase a (ec 3.1.1.4) of crotalus adamanteus to lysophosphatidic acid and 2-positioned fatty acids. from the analyses of the fatty acid composition of pyrophosphatidic acid and its degraded products (phosphatidid acid, lysophosphatidic acid, and fatty acid), it was concluded that most of the saturated fatty acids of pyrophosphatidic a ... | 1975 | 168186 |
| organization of phospholipids in human red cell membranes as detected by the action of various purified phospholipases. | 1. the action of eight purified phospholipases on intact human erythrocytes has been investigated. four enzymes, e.g. phospholipases a2 from pancreas and crotalus adamanteus, phospholipase c from bacillus cereus, and phospholipase d from cabbage produce neither haemolysis nor hydrolysis of phospholipids in intact cells. on the other hand, both phospholipases a2 from bee venom and naja naja cause a non-haemolytic breakdown of more than 50% of the lecithin, while sphingomyelinase c from staphyloco ... | 1975 | 169915 |
| search for relationships among the hemolytic, phospholipolytic, and neurotoxic activities of snake venoms. | several snake venom neurotoxins are larger and more complex than the well-studied group of postsynaptic toxins exemplified by alpha-bungarotoxin. several of these, exemplified by beta-bungarotoxin, show phospholipase a2 activity (phosphatide 2-acylhydrolase, ec 3.1.1.4) when tested in the presence of detergents. the high hemolytic activity of crotoxin, the neurotoxin of crotalus durissus terrificus, in the presence of lecithin has been attributed to this activity. the phospholipase a2 activity o ... | 1978 | 273221 |
| low concentrations of indomethacin inhibit phospholipase a2 of rabbit polymorphonuclear leukocytes. | inhibition of prostaglandin synthesis by indomethacin, a drug with anti-inflammatory properties, has been attributed to its action on fatty acid cyclooxygenase. however, prostaglandin synthesis would also be inhibited if precursor fatty acids were not supplied. we find that indomethacin inhibits phospholipase a2 (phosphatide 2-acylhydrolase, ec 3.1.1.4) of rabbit polymorphonuclear leukocytes in dose-dependent fashion. inhibition is immediate and readily detected at 1 micrometer. the extent of in ... | 1978 | 275865 |
| purification and some properties of two proteinases from crotalus adamanteus venom that inactivate human alpha 1-proteinase inhibitor. | two proteinases (proteinases i and ii) have been purified from crotalus adamanteus venom to the stage of electrophoretic homogeneity and proteinase ii has been crystallized. the proteinase differ slightly in molecular weight and amino acid composition. both are metalloenzymes requiring zn2+ or ca2+, or both; neither requires thiol compounds for activation. the proteinases are free of esterolytic activity against benzoly-l-arginine ethyl ester and benzoyl--tyrosine ethyl ester. proteinase ii clea ... | 1978 | 309470 |
| characterization of the inactive fragment resulting from limited proteolysis of human alpha1-proteinase inhibitor by crotalus adamanteus proteinase ii. | the inactive 50,000-dalton fragment of human plasma alpha1-proteinase inhibitor resulting from limited proteolysis of the inhibitor by crotalus adamanteus proteinase ii has been isolated and partially characterized. the amino acid composition of the inactivated inhibitor indicates the loss of a peptide fragment from the intact inhibitor. both intact and inactivated inhibitor contain cooh-terminal lysine. however, the nh2 terminus of the intact inhibitor is glx, whereas that of inactivated inhibi ... | 1979 | 447652 |
| trans fatty acids: positional specificity in brain lecithin. | fifteen-day-old rats were divided into three groups: one group received an intracerebral injection of 5 microci of 9-trans,12-trans [1-(14)c] octadecadienoic acid; the second group was given 5 microci of the same compound plus an equal wt of nonradioactive all cis arachidonic acid; the third group was given 5 microci of 9-trans [1-(14)c] octadecenoic acid. all animals were sacrificed 8 hr after injection. glycerophosphocholine (gpc) was isolated and partically deacylated with phospholipase a2 fr ... | 1979 | 449627 |
| in vitro actions of some antibiotics on phospholipases. | the effects of some antibiotics on activities of phospholipase a2, b and c were investigated in vitro. tetracyclines, macrolides, chloramphenicol and carbenicillin inhibited the activity of crotalus adamanteus phospholipase a2 towards phospholipids of egg-yolk emulsions. when the ability to inhibit the activity of penicillium notatum phospholipase b towards mixed micelles of phosphatidylcholine and triton x-100 was investigated, polymyxin b was found to be inhibitory while chloramphenicol and ca ... | 1979 | 541266 |
| positional and fatty acid specificity of monoacyl- and diacylglycerol 3-phosphate formation by rabbit heart microsomes. | fatty acid selectivity of acyl-coa:glycerol-3-phosphate acyltransferase (ec 2.3.1.15) and acyl-coa:monoacylglycerol-3-phosphate acyltransferase (ec 2.3.1.52) of the microsomal fraction prepared from rabbit heart was studied. 1. the rate of acylation of glycerol 3-phosphate was increased proportionally with the concentration of acyl-coa. the maximum rate was reached at 0.3 mumol acyl-coa per ml. palmitoyl-, oleoyl- and linoleoyl-coa all served equally well as acyl donors, and produced approximate ... | 1976 | 952977 |
| effects of local anaesthetics on phospholipases. | 1. the effects of six local anaesthetics have been studied on the activities of soluble phospholipases a2 (ec 3.1.1.4) and lysophospholipase (ec 3.1.1.5). 2. phospholipase a2 activity in human seminal plasma towards sonicated radioactively-labelled phosphatidylethanolamine was slightly stimulated a low and inhibited at high concentrations of all anaesthetic compounds employed. the order of decreasing potency was chlorpromazine, dibucaine, tetracaine, lidocaine, cocaine and procaine. in line with ... | 1976 | 952985 |
| characterization of a thrombin-like enzyme from crotalus adamanteus (eastern diamondback rattlesnake) [proceedings]. | | 1976 | 1014024 |
| relation between various phospholipase actions on human red cell membranes and the interfacial phospholipid pressure in monolayers. | the action of purified phospholipases on monomolecular films of various interfacial pressures is compared with the action on erythrocyte membranes. the phospholipases which cannot hyorolyse phospholipids of the intact erythrocyte membrane, phospholipase c from bacillus cereus, phospholipase a2 from pig pancreas and crotalus adamanteus and phospholipase d from cabbage, can hydrolyse phospholipid monolayers at pressure below 31 dynes/cm only. the phospholipases which can hydrolyse phospholipids of ... | 1975 | 1174576 |
| translocation and binding of adenine nucleotides by rat liver mitochondria partially depleted of phospholipids. | 1. rat liver mitochondria were partially depleted of their phospholipids using phospholipase a prepared from porcine pancreas (substrate specificity, cardiolipin greater than phosphatidylethanolamine greater than phosphatidylcholine) or from crotalus adamanteus venom (substrate specificity, phosphatidylethanolamine = phosphatidylcholine greater than cardiolipin). 2. removal of only about 1% of the mitochondrial phospholipid with the pancreatic enzyme leads to 50% and 25% losses in adp and atp tr ... | 1976 | 1259954 |
| transformation of n epsilon-cbz-l-lysine to cbz-l-oxylysine using l-amino acid oxidase from providencia alcalifaciens and l-2-hydroxy-isocaproate dehydrogenase from lactobacillus confusus. | biotransformations were developed to oxidize n epsilon-carbobenzoxy(cbz)-l-lysine and to reduce the product keto acid to l-cbz-oxylysine. lysyl oxidase (l-lysine: o2 oxidoreductase, ec 1.4.3.14) from trichoderma viride was relatively specific for l-lysine and had very low activity with n epsilon-substituted derivatives. l-amino acid oxidase (l-amino acid: o2 oxidoreductase [deaminating], ec 1.4.3.2) from crotalus adamanteus venom had low activity with l-lysine but high activity with n epsilon-fo ... | 1992 | 1368913 |
| evaluation of four different immunogens for the production of snake antivenoms. | four different immunogens were used to produce polyvalent antivenom in rabbits to the venoms of bothrops atrox, crotalus atrox, crotalus adamanteus and crotalus durissus terrificus. the immunogens were: (1) unfractionated mixture of the four crude venoms, and three fractions of the mixture as follows, (2) hplc gel filtration high (> 50,000) mol. wt fraction, (3) hplc gel filtration medium (14,000-50,000) mol. wt fraction, and (4) hplc gel filtration low (< 14,000) mol. wt fraction. the resultant ... | 1992 | 1485332 |
| sphingolipid metabolism and signal transduction: inhibition of in vitro phospholipase activity by sphingosine. | sphingosine inhibits protein kinase c activity in vitro and has been used to implicate this enzyme in signal transduction and cell function. we report that sphingosine directly inhibits phospholipases a2 and d. sphingosine inhibits ca(2+)-dependent phospholipases a2 from naja naja, porcine pancreas, crotalus adamanteus, human disc and neutrophil in a dose-dependent manner with ic50 values ranging from 5-40 microm using [1-14c]oleate-labelled autoclaved e. coli (20 microm) as substrate. inhibitio ... | 1992 | 1504102 |
| an immunohistochemical study of phospholipase a2 in peripheral nerve during wallerian degeneration. | antiserum raised against purified crotalus adamanteus venom phospholipase a2 (pla2) was used to localise the enzyme in normal and crushed sciatic nerve to determine the effect of nerve trauma on pla2 distribution in the pns. the tissue was bouin's fixed, and stained immunohistochemically using the vectastain abc technique. anti-pla2 antiserum showed weak reactivity with normal rat myelin, while only 'resident' macrophages stained in normal mouse sciatic nerve. post-crush, in the mouse, myelin st ... | 1992 | 1619038 |
| peroxidation and phospholipase a2 hydrolytic susceptibility of liposomes consisting of mixed species of phosphatidylcholine and phosphatidylethanolamine. | the relationship between lipid peroxidation and phospholipase a2 (pla2) hydrolytic activity was studied using unilamellar vesicles (liposomes) as model membranes. hydrolytic specificity was examined using vesicles prepared with pure bovine heart phosphatidylcholine (pc), bovine heart phosphatidylethanolamine (pe), or mixtures of these phospholipids, using two preparative procedures, i.e., sonication or extrusion. lipid peroxidation was induced by incubating vesicles with cumene hydroperoxide and ... | 1992 | 1643097 |
| reversibility of the activation of soluble phospholipase a2 on lipid bilayers: implications for the activation mechanism. | the time-courses of hydrolysis of large vesicles of dipalmitoylphosphatidylcholine were compared using four species of phospholipase a2 (agkistrodon piscivorus piscivorus, crotalus adamanteus and naja naja venoms and porcine pancreatic). in all four cases, the hydrolysis rate suddenly increases 10 to 100-fold at the time (tau) when a specific mole fraction of reaction products has accumulated. the intrinsic fluorescence emission of the three venom enzymes also increases suddenly at time tau. bot ... | 1992 | 1643108 |
| identification of a 15-kilodalton surface glycoprotein on sporozoites of cryptosporidium parvum. | an immunoglobulin a monoclonal antibody (mab5c3) was developed against a 15-kda surface glycoprotein (gp15) of cryptosporidium parvum sporozoites. indirect immunofluorescence and colloidal gold immunoelectron microscopy revealed that the antibody reacted with both the sporozoite and merozoite surface plasma membranes. on western immunoblots, mab5c3 binding was found to be strongly inhibited when 200 mm n-acetylglucosamine was used as a competing sugar. n-acetylgalactosamine inhibited binding of ... | 1991 | 1705238 |
| regional differences in content of small basic peptide toxins in the venoms of crotalus adamanteus and crotalus horridus. | 1. reverse-phase hplc and organic solvents were used to isolate small basic peptide (sbp) toxins from the venoms of crotalus adamanteus, c. durissus terrificus, c. horridus, c. scutulatus scutulatus, c. viridis concolor, c. viridis helleri and c. viridis viridis. 2. acid-dep analyses indicated a high degree of toxin purity which was obtained with a single hplc run. 3. the combined results of hplc, immunodiffusion and electrophoresis analyses of venoms from different geographical regions indicate ... | 1991 | 1756621 |
| interleukin-1 alpha stimulates the release of prostaglandin e2 and phospholipase a2 from fetal rat calvarial cells in vitro: relationship to bone nodule formation. | we have shown previously that interleukin-1 (il-1) has biphasic effects on the formation of bone nodules in long-term cultures of fetal rat calvarial (rc) cells (ellies and aubin, cytokine 2:430-437, 1990). to determine the role of arachidonic acid metabolism in this process, we have examined the release of prostaglandin e2 (pge2) and phospholipase a2 (pla2) from rc cells under conditions that allowed concomitant analysis of the formation of bone nodules. recombinant human il-1 alpha (rhil-1 alp ... | 1991 | 1785374 |
| neutralization of kinin-releasing enzymes of crotalid venoms by monospecific and polyspecific antivenoms. | the amounts of kinin-releasing enzymes in the venoms of crotalus atrox, crotalus adamanteus, crotalus scutulatus scutulatus and agkistrodon piscivorus piscivorus were measured by determining the amounts of kinin released from a sheep kininogen substrate by means of a specific radioimmunoassay. four monospecific and two commercial polyspecific antivenom igg samples were tested for their ability to reduce the kinin-releasing activities of the four crotalid venoms measured in vitro. all of the anti ... | 1991 | 1926178 |
| behaviour of phospholipase modified-hdl towards cultured hepatocytes. ii. increased cell cholesterol storage and bile acid synthesis. | human total hdl (hydrated density 1.070-1.210), hdl2 (1.070-1.125), hdl3 (1.125-1.210) or hdl separated by heparin affinity chromatography were treated with or without purified phospholipase a2 from crotalus adamanteus. control and treated hdl were reisolated and were then incubated with cultured hepatocytes. 1. mass measurements evidenced a time-dependent cholesterol enrichment in hepatocytes cultured in the absence of lipoproteins. addition of hdl2 still enhanced by 25% the cell cholesterol co ... | 1991 | 1998740 |
| selective inhibition of receptor-coupled phospholipase c-dependent processes in human platelets and polymorphonuclear neutrophils. | aggregation of human platelets induced by a variety of agonists was inhibited by 1-[6-[[17 beta-3-methoxyestra-1,3,5(10)-trien-17-yl] amino]hexyl]-1h-pyrrole-2,5-dionel (u-73122) (ic50 values 1-5 microm), but not by the close analog 1-[6-[[17 beta-3-methoxyestra- 1,3,5(10)-trien-17-yl]amino]hexyl]-2,5-pyrrolidine-dione (u-73343) in which pyrrolidinedione was substituted for pyrroledione. inhibition by u-73122 was not mediated by an increase in intracellular cyclic amp. in contrast, the productio ... | 1990 | 2147038 |
| purification and characterization of a soluble phospholipase a2 from guinea pig lung. | guinea pig lung cytosolic phospholipase a2 was purified to near homogeneity by chromatography on a phosphocellulose column, followed by q-sepharose, s-sepharose, gel filtration chromatography and reverse-phase hplc. the purified enzyme exhibited an apparent molecular weight of 16,700 by sds-polyacrylamide gel electrophoresis. active enzyme eluted from the gel at an apparent molecular weight of 16,700. the purified enzyme exhibited a ph optimum of 9.0 and was calcium-dependent. guinea pig lung ph ... | 1990 | 2252913 |
| behaviour of phospholipase-modified hdl towards cultured hepatocytes. i. enhanced transfers of hdl sterols and apoproteins. | human hdl subfractions (hdl2, hdl3, or hdl separated by heparin affinity chromatography) were labelled either on their apolipoprotein moiety with 125i or on their sterols: unesterified [14c]cholesterol and [3h]cholesteryl linoleyl ether, a non-hydrolysable analog of esterified cholesterol. hdl subfractions were then treated with or without phospholipase a2 from crotalus adamanteus in presence of albumin leading to a 72-82% phosphatidylcholine degradation. control and treated hdl were reisolated ... | 1990 | 2322573 |
| comparison of the immunogenicity and antigenic composition of several venoms of snakes in the family crotalidae. | crude venoms from the prairie rattlesnake (crotalus viridis viridis), the western diamondback rattlesnake (crotalus atrox), the eastern diamondback rattlesnake (crotalus adamanteus) and the timber rattlesnake (crotalus horridus horridus) were used to prepare monovalent antivenoms in rabbits. each of these four monovalent antivenoms was reacted against six different venoms using the technique of immunoblotting (western blot) to determine the relative immunogenicity of the four venoms and to compa ... | 1990 | 2339435 |
| purification and partial characterization of the hemorrhagic factor from the venom of crotalus adamanteus (eastern diamondback rattlesnake). | a proteinase from crotalus adamanteus venom has been isolated to the stage of electrophoretic homogeneity by chromatography of the crude venom on cm-sepharose, phenyl-sepharose, ultrogel aca 44 and deae-sepharose. the proteinase accounts for 100% of the detectable hemorrhagic activity in the venom, and the name c. adamanteus proteinase h is suggested. proteinase h is a single chain glycoprotein with a molecular weight of 85,700. proteinase h is active on casein and hide powder azure, but does no ... | 1985 | 2414864 |
| effects of exogenous phospholipase enzymes, arachidonic acid and 1-oleoyl-2-acetyl-sn-glycerol on ketogenesis in isolated rat hepatocytes. | studies were conducted to see whether exogenous phospholipase c from clostridium perfringens, phospholipase a2 from crotalus adamanteus venom, arachidonic acid and 1-oleoyl-2-acetyl-sn-glycerol (oag) mimic the anti-ketogenic action of vasopressin in isolated rat hepatocytes. exogenous phospholipase c inhibited ketogenesis in the presence of 0.5 mm oleate. experiments employing [1-14c]oleate, however, indicated that the mechanism involved in the anti-ketogenic action of exogenous phospholipase c ... | 1989 | 2499356 |
| effects of mepacrine on the oxidation of [1-14c]oleate in isolated rat hepatocytes. | in isolated rat hepatocytes, mepacrine stimulated the conversion of [1-14c]oleate into 14co2 and depressed the formation of acid-soluble products from [1-14c]oleate. the action of mepacrine on [1-14c]oleate oxidation was not affected by exogenously applied phospholipase a2 (from crotalus adamanteus venom) or arachidonic acid. it is suggested that mepacrine may exert its metabolic effects in isolated rat hepatocytes by a mechanism independent of phospholipase a2 inhibition. | 1989 | 2503651 |
| hydrolysis of a phospholipid in an inert lipid matrix by phospholipase a2: a 13c nmr study. | a new approach to study phospholipase a2 mediated hydrolysis of phospholipid vesicles, using 13c nmr spectroscopy, is described. [13c]carbonyl-enriched dipalmitoylphosphatidylcholine (dppc) incorporated into nonhydrolyzable ether-linked phospholipid bilayers was hydrolyzed by phospholipase a2 (crotalus adamanteus). the 13c-labeled carboxyl/carbonyl peaks from the products [lyso-1-palmitoylphosphatidylcholine (lppc) and palmitic acid (pa)] were well separated from the substrate carbonyl peaks. th ... | 1989 | 2790021 |
| conversion of 6-mercaptopurine to 6-thioguanylic acid in l-1210 cells and human leukemia cells. | the metabolism of 6-mercaptopurine (6-mp) in l-1210 mouse leukemia cells and human chronic myelocytic leukemia cells (cml cells) was examined. the acid-soluble fractions obtained from cells incubated with [8-14c]6-mp were chromatographed on a dowex-1 formate resin column using a formic acid linear gradient elution system. chromatography of the extract of l-1210 cells revealed four principal radioactive peaks. the fraction containing the third peak was hydrolyzed by snake venom 5'-nucleotidase (c ... | 1985 | 2858424 |
| fluorometric assay for adp-ribosylarginine cleavage enzymes. | a continuous fluorometric assay for enzyme activities which remove adp-ribose linked to proteins at arginine was developed. the substrate analog, n alpha-dansyl-n omega-(1,n6-etheno-adp-ribosyl)arginine methyl ester, was used to assay the catalytic activities of dinitrogenase reductase activating glycohydrolase from rhodospirillum rubrum and nucleotide pyrophosphatase from crotalus adamanteus. the assay is based on the increase in fluorescent emission by ethenoadenine accompanying the enzyme-cat ... | 1987 | 3032020 |
| cross-reactivity and neutralization by rabbit antisera raised against crotoxin, its subunits and two related toxins. | antisera were raised against intact crotoxin (crotalus durissus terrificus), mojave toxin (crotalus scutulatus scutulatus) and concolor toxin (crotalus viridis concolor), as well as the subunits of crotoxin. double immunodiffusion and enzyme-linked immunosorbent assays (elisa) demonstrated antigenic similarity between these three purified toxins and their subunits. additionally, when crotoxin antisera were pre-incubated with each of the three toxins before injection, the lethal activity of all w ... | 1986 | 3095955 |
| amino acid sequence of trimeresurus flavoviridis phospholipase a2. | the amino acid sequence of phospholipase a2 from the venom of trimeresurus flavoviridis (the habu snake) was determined. the enzyme subunit has a molecular weight of 13,764 and consists of a single polypeptide chain of 122 amino acids and seven disulfide bonds. the fragmentation was conducted by digesting the reduced and s-carboxymethylated derivative of the protein with achromobacter protease i, chymotrypsin, and trypsin, respectively. achromobacter protease i peptides were used for alignment a ... | 1986 | 3514593 |
| helodermatine, a kallikrein-like, hypotensive enzyme from the venom of heloderma horridum horridum (mexican beaded lizard). | we have purified and characterized the major n-benzoyl-l-arginine ethyl ester hydrolase from the venom of heloderma horridum horridum. the enzyme belongs to the serine proteinase family, and its activity vs. peptide amide substrates and human high-molecular-weight kininogen suggests a similarity to the family of kallikreins. this interpretation is corroborated by its reactivity with the natural inhibitors soybean trypsin inhibitor and kunitz-type bovine pancreatic trypsin inhibitor (aprotinin). ... | 1986 | 3537191 |
| antitumor action of crotalase, a defibrinogenating snake venom enzyme. | recent reports have shown that malignant cells release a variety of factors that modulate the tumor microenvironment. these factors, after release or shedding, work in concert to produce extravasation of fibrinogen from surrounding blood vessels with subsequent fibrin deposition around the tumor cells. this fibrin deposit could act to mask the tumor from the host's immune surveillance system. fibrin deposits have been observed by investigators in the vicinity of various malignant tumors of man a ... | 1986 | 3538422 |
| the action of various venoms on escherichia coli. | the antibacterial activity of honeybee venom (apis mellifera), three snake venoms (naja naja sputatrix, vipera russellii and crotalus adamanteus) and the polypeptide melittin was investigated against escherichia coli. minimum inhibitory concentration values, cell lysis and alterations in cell permeability were determined and action against e. coli was in the order: a. mellifera venom greater than melittin greater than n. naja sputatrix venom much greater than v. russellii venom greater than c. a ... | 1986 | 3542922 |
| synthesis of prodan-phosphatidylcholine, a new fluorescent probe, and its interactions with pancreatic and snake venom phospholipases a2. | a new fluorescent probe, prodan-pc, was synthesized by incubating thio-pc, a thiol ester analogue of phosphatidylcholine [1,2-bis(decanoylthio)-1,2-dideoxy-sn-glycero-3-phosphocholine], with acrylodan, a fluorescent thiol-reactive reagent [6-acryloyl-2-(dimethylamino)naphthalene], in the presence of phospholipase a2, which served to generate lysothio-pc in situ. prodan-pc (ppc) showed maximum absorption in ethanol at 370 nm. the fluorescence emission spectrum showed maximum emission at 530 nm in ... | 1987 | 3651404 |
| stereospecific analysis of fatty acid esters of chloropropanediol isolated from fresh goat milk. | the fatty acid esters of chloropropanediol isolated from goat milk fat in small quantities were subjected to a stereospecific analysis via phospholipase c and phosphocholine esters as intermediates. synthetic rac-1-chloro-2,3-dioleoyl-propanediol was prepared by standard methods and was used as a control. the stereospecific analyses were performed following a release of the fatty acids from the primary positions of each chloropropanediol diester with pancreatic lipase. the resulting x-1-chloro-2 ... | 1986 | 3724368 |
| distribution of high-density lipoprotein 2 and 3 constituents during in vitro phospholipid hydrolysis. | human high-density lipoproteins hdl2 (d = 1.068-1.125) and hdl3 (d = 1.125-1.210) doubly labelled with [3h]cholesterol/cholesteryl ester and with [acyl-14c]phosphatidylcholine were further incubated with phospholipases. highly purified phospholipase a2 from crotalus adamanteus allowed gradual degrees of lipolysis (30-90%) on both hdl2 and hdl3. moderate phospholipid hydrolyses were achieved using hepatic triacylglycerol lipase, partially purified from post-heparin plasma. moreover, the latter en ... | 1987 | 3803386 |
| determination of the protein content of crystals formed by mastigocladus laminosus c-phycocyanin, chroomonas spec. phycocyanin-645 and modified human fibrinogen using an improved ficoll density gradient method. | we demonstrated for several protein crystals of known protein content that the simple ficoll density gradient method for crystal density determination as described by westbrook (1976) often leads to quite erroneous results. in particular, the apparent density of loosely packed crystals can show a tremendous change within the first minutes of measurement. in order to derive the correct protein content the apparent crystal density must be followed as a function of time and has to be extrapolated b ... | 1985 | 3924073 |
| aggregation studies on fluorescein-coupled cobra venom phospholipase a2. | phospholipase a2 from naja naja naja venom (indian cobra) undergoes a concentration-dependent aggregation, and at an assay concentration of 1 microgram ml-1, it exists as a monomer. however, there is some evidence that the enzyme is actually active as a dimer or higher order aggregate. previous attempts to determine the aggregation state of the enzyme under actual assay conditions were thwarted by experimental difficulties due in part to the low enzyme concentrations required. this aggregation h ... | 1985 | 3936540 |
| activation, aggregation, and product inhibition of cobra venom phospholipase a2 and comparison with other phospholipases. | the kinetics of phospholipid hydrolysis by cobra venom phospholipase a2 were examined and compared to those of phospholipase a2 from porcine pancreas, crotalus adamanteus (rattlesnake) venom, and bee venom. only the enzyme from naja naja naja (cobra) venom was found to be activated significantly by phosphorylcholine-containing compounds when hydrolyzing phosphatidylethanolamine. the cobra venom enzyme was also the only one in which these activators induced protein aggregation. the parallel speci ... | 1985 | 4030786 |
| biosynthetic incorporation of cis-parinaric acid into radioactive sn-3-phosphatidic acid. | isolated guinea pig liver microsomal membranes catalyzed the incorporation of naturally occurring cis-parinaric acid into sn-3-[u-14c]glycerophosphate. this resulted in the formation of sn-3-[14c](parinaroyl)phosphatidic acid, which was isolated by chelex-100 and deae-cellulose column chromatography and further purified by sephadex-g 25. the sn-3-[14c](parinaroyl)phosphatidic acid thus obtained exhibited absorption and fluorescence spectra substantially different from the cis-parinaric acid. dis ... | 1985 | 4034509 |
| crotalus adamanteus basic protein toxin: electron microscopic evaluation of myocardial damage. | | 1973 | 4125228 |
| a new acute phase protein elicited in mice by streptolysin o and other toxic or infectious agents. | a new acute phase plasma component has been found in mice exposed to certain toxic materials and pathogenic bacteria. the abnormal component, detected by immunodiffusion employing absorbed antiserum, was chiefly studied in plasma of streptolysin o-treated mice where it appears within 24 hours after intravenous administration of a sublethal dose of the toxin. the new factor is a protein having the electrophoretic mobility of a slow alpha2-globulin. it is devoid of lipid and separate from the stre ... | 1965 | 4158436 |
| thrombic enzyme from crotalus adamanteus. | | 1970 | 4194151 |
| a purified procoagulant enzyme from the venom of the eastern diamondback rattlesnake (crotalus adamanteus): in vivo and in vitro studies. | | 1972 | 4623612 |
| distribution and excretion of 3h-venoms of crotalus adamanteus, crotalusatrox, and agkistrodon piscivorus and 3h-serum of lampropeltis getulus in rats. | | 1972 | 5058627 |
| afibrinogenemia in man following the bite of a rattlesnake (crotalus adamanteus). | | 1969 | 5822979 |
| the diagnosis, symptoms, treatment and sequella of envenomation by crotalus adamanteus and genus agkistrodon. | | 1966 | 6004039 |
| studies on the complex between human alpha 2-macroglobulin and crotalus adamanteus proteinase ii. release of active proteinase from the complex. | proteinase ii from crotalus adamanteus venom formed a complex with human alpha 2-macroglobulin in which approx. 1.7 mol of enzyme were bound per mol inhibitor. the complex did not enzymatically inactivate human alpha 1 proteinase inhibitor. however, active proteinase ii was released from the complex in the presence of a high molecular weight proteinase fraction from c. adamanteus venom. the alpha 2-macroglobulin-proteinase ii complex was also unstable during incubation in serum, and the enzyme r ... | 1980 | 6160877 |
| venom exonuclease. iii. immunochemical characterization and modification by specific antibody. | the immunoelectrophoretic purity of the exonuclease preparation, isolated from crotalus adamanteus venom according to a procedure previously published (dolapchiev, l.b., sulkowski, e. and laskowski, m., sr. (1974) biochem. biophys. res. commun. 61, 271-281), is reported. the enzyme showed one precipitin line against antibody prepared against partially purified venom. the exonuclease is unstable in dilute (1.25 microgram/ml and below) solutions. bovine serum albumin stabilized the enzyme nonspeci ... | 1981 | 6163475 |
| modification of the tetrodotoxin receptor in electrophorus electricus by phospholipase a2. | the effects of phospholipase a2 treatment on the tetrodotoxin receptors in electrophorus electricus was studied. (1) the binding of [3h]tetrodotoxin to electroplaque membranes was substantially reduced by treatment of the membranes with low concentrations of phospholipase a2 from a number of sources, including bee venom, vipera russelli and crotalus adamanteus and by beta-bungarotoxin. (2) phospholipase a2 from bee venom and from c. adamanteus both caused extensive hydrolysis of electroplaque me ... | 1981 | 6268164 |
| a simple and versatile affinity column for phospholipase a2. | an affinity adsorbent for phospholipase a2 (ec 3.1.1.4) was prepared by reacting 10-o-p-toluenesulfonyldecane-1-o-phosphocholine with ah-sepharose 4b. phospholipases a2 bind to the immobilized ligand in the presence of ca2+ and can be eluted with buffers containing edta. this principle held not only for soluble phospholipase a2 from porcine pancreas and crotalus adamanteus, but proved also effective in the purification of phospholipases a2 solubilized from the membranes of rat liver mitochondria ... | 1984 | 6421328 |
| local necrotizing effect of snake venoms on skin and muscle: relationship to serum creatine kinase. | twenty-five snake venoms were tested for their ability to induce an increase of serum creatine kinase (ck) level after i.m. injection (0.125-1.0 mg/kg) into rates. of six australian elapid venoms only those from pseudechis colletti guttatus and p. australis produced a steep rise of ck-activity (30-70 times the normal value) 4 and 16 hr after injection (0.5 mg/kg). viperid and crotalid venoms had only slight effects (2-5 times the normal value) even in doses of 1.0 mg/kg except for a sample of cr ... | 1983 | 6623487 |
| facilitation of phospholipase a2 activity by mastoparans, a new class of mast cell degranulating peptides from wasp venom. | the effect of mastoparan, ile-asn-leu-lys-ala-leu-ala-ala-leu-ala-lys-lys-ile-leunh2, and related peptides on the release of arachidonic acid from egg yolk lecithin liposomes, rat peritoneal mast cells, and cultured human fibroblasts was studied. in unsonicated liposomes, labeled with 1-stearoyl-2[1-14c]arachidonyl-sn-glycero-3-phosphocholine, 5 x 10(-5) m mastoparan caused a 12-, 15-, and 50-fold increase in the production of arachidonic acid catalyzed by phospholipase a2 from bee venom, easter ... | 1983 | 6643447 |
| phospholipids chiral at phosphorus. preparation and spectral properties of chiral thiophospholipids. | the thiophospholipid 1,2-dipalmitoyl-sn-glycero-3-thiophosphocholine (dppsc) was shown to be a mixture of two diastereomers by 31p nuclear magnetic resonance. the isomer that resonates at the lower field in cdcl3 (56.12 ppm) was designated as isomer a and the other (resonates at 56.07 ppm) as isomer b. phospholipase a2 from four different sources (bee venom, naja naja venom, crotalus adamanteus venom, and porcine pancreas) was shown to hydrolyze the isomer b of dppsc specifically, whereas phosph ... | 1983 | 6688028 |
| identification of the cleavage sites resulting from enzymatic inactivation of human antithrombin iii by crotalus adamanteus proteinase ii in the the presence and absence of heparin. | | 1981 | 7034776 |
| kallikrein-like activity of crotalase, a snake venom enzyme that clots fibrinogen. | during the amino acid sequence determination of crotalase (ec 3.4.21.30), the thrombin-like enzyme from the venom of crotalus adamanteus (eastern diamondback rattlesnake), we found that, in addition to the expected structural homology with bovine thrombin (ec 3.4.21.5), there was even greater homology with porcine pancreatic kallikrein (ec 3.4.21.8). in exploring further the similarities between crotalase and kallikrein, several striking observations were made. first, crotalase was rapidly and s ... | 1982 | 7043462 |
| early management of bites by the eastern diamondback rattlesnake (crotalus adamanteus): studies in monkeys (macaca fascicularis). | monkeys were injected subcutaneously with 6 mg of crotalus adamanteus venom and a solid phase radioimmunoassay was used to measure levels of venom in plasma and urine. when no attempt was made to retard venom movement from the site of injection, plasma levels as high as 1,300 ng/ml occurred within 15 min of injection and progressive swelling developed in the injected limb. when first aid was employed (firm pressure to the injection site and immobilization of limb with a splint), plasma levels re ... | 1981 | 7235137 |
| uptake of phospholipid-depleted chylomicrons by the perfused rat liver. | 1. rat lymph chylomicrons were depleted of their surface phospholipids by treatment with pure phospholipase a2 from crotalus adamanteus venom. 2. about 80% of the phospholipids could be removed from the chylomicrons without any apparent effect on their size, neutral lipid composition or qualitative profile of their tetramethylurea-soluble apoproteins. 3. phospholipid-depleted chylomicrons were rapidly taken up whole by liver cells when perfused through isolated rat liver preparations. the rate o ... | 1980 | 7236241 |
| phospholipase a2 activity on mixed lipid monolayers: inhibition and activation of phospholipases a2 from porcine pancreas and crotalus adamanteus by anionic and neutral amphiphiles. | | 1981 | 7325675 |
| immunohistochemical localization of phospholipase a2 in human and bovine male reproductive organs. | phospholipase a2 (pla2) taken from human seminal plasma and purified about 1450-fold was injected into rabbits to prepare polyclonal antibodies. the antiserum produced and the igg purified from the antiserum were used to compare the immunohistochemical localization of pla2 in the human male reproductive system with that in the bull. in western blot analyses, the polyclonal antibodies cross-reacted with purified pla2s from human seminal plasma, bovine cowper's glands and with partly purified pla2 ... | 1995 | 7584826 |
| human pancreatic phospholipase a2 stimulates the growth of human pancreatic cancer cell line. | phospholipase a2 (pla2) from human pancreas, designated hpla2-i, functions as a digestive enzyme. interestingly, the present study demonstrated that the mature form of hpla2-i stimulated the growth of a human pancreatic cancer cell line miapaca-2, whereas the pro-form was ineffective. pla2s from laticauda semifasciata fraction i, crotalus adamanteus venom, streptomyces violaceoruber and bee venom, showed no proliferative effect to the growth of miapaca-2. the scatchard plot analysis revealed tha ... | 1995 | 7589440 |
| differential hydrolysis of immobilized phosphatidylcholines by phospholipases a2 and c. | a novel phospholipid, 1-fatty acyl-2-(12-aminododecyl) phosphatidylcholine (apc), was synthesized and reacted with two different activated agarose matrices, differing in the spacer arm length: n-hydroxysuccinimidylester agarose (1-atom spacer arm) and n-hydroxysuccinimidylester-6-aminohexanoic acid agarose (8-atom spacer arm). both immobilized phosphatidylcholines were readily degraded by bacillus cereus phospholipase c at similar rates. by contrast, crotalus adamanteus phospholipase a2 hydrolyz ... | 1994 | 7999009 |
| 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 |
| toxic effects of human pancreatic and snake and bee venom phospholipases a2 on mcf-7 cells in culture. | the toxicity of phospholipase a2 (pla2) has been suggested to be involved in the pathology of a number of severe diseases including septic shock and acute pancreatitis. however, testing the toxicity of these substances is difficult in vivo. in the present study we compared the toxicity of pla2s from three snake venoms, bee venom and human pancreas on mcf-7 cells grown in culture. tetrazolium microculture assays were developed to test the cytostatic and cytotoxic effects of pla2 on mcf-7 cells. t ... | 1993 | 8212029 |
| first structure of a snake venom metalloproteinase: a prototype for matrix metalloproteinases/collagenases. | adamalysin ii, a 24 kda zinc endopeptidase from the snake venom of crotalus adamanteus, is a member of a large family of metalloproteinases isolated as small proteinases or proteolytic domains of mosaic haemorrhagic proteins from various snake venoms. homologous domains have recently been detected in multimodular mammalian reproductive tract proteins. the 2.0 a crystal structure of adamalysin ii reveals an ellipsoidal molecule with a shallow active-site cleft separating a relatively irregularly ... | 1993 | 8223430 |
| role of lipid structure in the activation of phospholipase a2 by peroxidized phospholipids. | the time course of hydrolysis of a mixed phospholipid substrate containing bovine liver 1,2-diacyl-sn-glycero-3-phosphocholine (pc) and 1,2-diacyl-sn-glycero-3-phosphoethanolamine (pe) catalyzed by crotalus adamanteus phospholipase a2 was measured before and after peroxidation of the lipid substrate. the rate of hydrolysis was increased after peroxidation by an iron/adenosine diphosphate (adp) system; the presence of iron/adp in the assay had a minimal inhibitory effect. the rate of lipid hydrol ... | 1993 | 8355576 |
| immature ixodes scapularis (acari: ixodidae) parasitizing lizards from the southeastern u.s.a. | preserved museum specimens of 13 lizard and 3 snake species common in the southeastern u.s.a. were examined for immature ixodes scapularis say ticks. five eumeces and 4 ophisaurus lizard species yielded an infestation prevalence of 17.8% for species of eumeces and 29.0% for species of ophisaurus. mean intensity of larvae and nymphs was 7.1 and 2.7, respectively, for species of eumeces, and 6.3 and 1.4, respectively, for species of ophisaurus. collection dates of the lizards ranged from january t ... | 1993 | 8410539 |
| the role of phospholipase a2 in interleukin-1 alpha-mediated inhibition of mineralization of the osteoid formed by fetal rat calvaria cells in vitro. | interleukin-1 (il-1) may be an important mediator of bone remodeling, since it is a potent stimulator of bone resorption and has biphasic effects on bone formation. continuous exposure of fetal rat calvaria (rc) cells to il-1 alpha or il-1 beta results in a dose-dependent inhibition of both bone nodule formation and mineralization of the organic matrix. in this study, the effects of recombinant human il-1 alpha on the mineralization process were examined by the addition of il-1 alpha late in the ... | 1993 | 8418103 |
| immunohistochemical study of phospholipase a2 in bovine prostate. | approximately 1,100-fold purified phospholipase a2 (pla2) from bovine prostate was injected into rabbit to prepare polyclonal antibodies. antibodies produced showed specific immunoprecipitation only with the purified enzyme, as well as with homogenate of bovine prostatic tissue. by western blot analysis or by immunodiffusion test, no cross-reactivity with pla2 purified from human seminal plasma, bovine pancreas, crotalus adamanteus venom, or with partially purified pla2 from bovine seminal vesic ... | 1993 | 8488158 |
| differential effects of glycero- and sphingo-phospholipolysis on human high-density lipoprotein fluidity. | this study investigates the effect of enzymatic modifications of the hdl(3) surface lipid composition on their physical properties. human hdl(3) (d: 1.125-1.21 g/ml) was treated either by an exogenous phospholipase a(2) from crotalus adamanteus or by a sphingomyelinase from staphylococcus aureus in the presence of albumin for various periods of time in order to obtain several degrees of hydrolysis. glycerophospholipid hydrolysis ranged from 13 to 81% and sphingomyelinase action led to a 31-92% s ... | 1996 | 8652647 |
| [biochemical studies on functional proteins in the brain nervous system. neurobiochemical studies on nerve growth factor]. | nerve growth factor (ngf) is a polypeptide that is necessary for the survival and growth of developing sympathetic and sensory neurons as well as basal forebrain cholinergic neurons in the brain. the effects of ngf are mediated by the binding of the factor to its specific receptor present on the surface of ngf-responsive cells. since ngf-responsive basal forebrain cholinergic neurons are lost in alzheimer's disease, treatment with ngf may be therapeutically beneficial for the patients with this ... | 1996 | 8709005 |
| effect of crotapotin and heparin on the rat paw oedema induced by different secretory phospholipases a2. | the effects of crotapotin (a non-toxic and non-enzymatic acid polypeptide naturally complexed with phospholipase a2) and heparin on rat paw edema induced by different secretory phospholipases a2 (spla2) have been investigated. the ability of crotapotin to affect the enzymatic activity of the spla2(s) have also been evaluated. secretory pla2(s) obtained from both snake (naja naja, naja mocambique mocambique, crotalus adamanteus and crotalus durissus terrificus) and bee (apis mellifera) venoms as ... | 2000 | 10665801 |
| structural and functional characterization of neuwiedase, a nonhemorrhagic fibrin(ogen)olytic metalloprotease from bothrops neuwiedi snake venom. | a fibrino(geno)lytic nonhemorrhagic metalloprotease (neuwiedase) was purified from bothrops neuwiedi snake venom by a single chromatographic step procedure on a cm-sepharose column. neuwiedase represented 4.5% (w/w) of the crude desiccated venom, with an approximate mr of 20,000 and pi 5.9. as regards the amino acid composition, neuwiedase showed similarities with other metalloproteases, with high proportions of asx, glx, leu, and ser. atomic absorption spectroscopy showed that one mole of zn2+ ... | 2000 | 11032408 |
| bioactivation of chemopreventive selenocysteine se-conjugates and related amino acids by amino acid oxidases novel route of metabolism of selenoamino acids. | several selenocysteine se-conjugates have been shown to possess potent chemopreventive activity in animal models for chemical carcinogenesis. as a mechanism of action, beta-elimination reactions to form chemopreventive selenols, ammonia, and pyruvate has been proposed. the enzymes involved in these beta-elimination reactions, however, have been partially elucidated. next to cysteine conjugate beta-lyases, as yet unidentified non-pyridoxal-5'-phosphate-dependent enzymes also appear to be involved ... | 2001 | 11511173 |
| oxidative events cause degradation of apob-100 but not of apo[a] and facilitate enzymatic cleavage of both proteins. | lipoprotein [a] (lp[a]) contains equimolar amounts of apob-100 and apolipoprotein [a] (apo[a]). both proteins are amenable to degradation in vivo by mechanisms yet to be clearly defined. in this study, we examined the in vitro susceptibility of ldl and lp[a], obtained from the same donor, to oxidation by either cu(2)+ or the combined crotalus adamanteus phospholipase a2 and soybean lipoxygenase system, monitoring the course of the reaction by the generation of conjugated dienes and fatty acids. ... | 2001 | 11590223 |
| a snake venom phospholipase a(2) blocks malaria parasite development in the mosquito midgut by inhibiting ookinete association with the midgut surface. | oocyst formation is a critical stage in the development of the malaria parasite in the mosquito. we have discovered that the phospholipase a(2) (pla2) from the venom of the eastern diamondback rattlesnake (crotalus adamanteus) inhibits oocyst formation when added to infected chicken blood and fed to mosquitoes. a similar transmission-blocking activity was demonstrated for pla2s from the venom of other snakes and from the honeybee. this effect is seen both with the avian malaria parasite plasmodi ... | 2001 | 11809789 |
| inhibition of contact hypersensitivity reaction to picryl chloride: effect of small molecular weight peptidomimetic compounds possessing inhibitory activity against metalloproteinases. | we have studied the effect of small molecular weight inhibitors of snake venom metalloproteinases (svmp) and matrix metalloproteinases (mmps) on the induction and effector phase of the contact hypersensitivity reaction (chr) in a mouse model. identification of nonsteroid small molecules is very important for the development of new anti-inflammatory drugs. the compounds that we tested were synthetically modified tripeptides (peptidomimetic compounds) pol-257, pol-509, pol-443, pol-491, and pol-64 ... | 2002 | 12013508 |
| cross reactivity of three antivenoms against north american snake venoms. | the antivenom in the united states today is in short supply, expensive and may not even be the most effective in neutralizing venoms from snakes in certain geographical locations. the ed(50) is considered to be the best indicator of antivenom efficacy, however, other tests are needed. in this study, three antivenoms (antivipmyn (fab(2)h), crotalidae polyvalent immune fab (ovine) (fabo) and ucv (fabv) were used to test the effectiveness of neutralization of eight venoms (agkistrodon piscivorus pi ... | 2003 | 12565754 |
| preclinical assessment of the ability of polyvalent (crotalinae) and anticoral (elapidae) antivenoms produced in costa rica to neutralize the venoms of north american snakes. | polyvalent (crotalinae) and anticoral (elapidae) antivenoms produced by instituto clodomiro picado, costa rica, were assessed for their ability to neutralize various toxic activities of the venoms of north american snakes of the genera crotalus, agkistrodon and micrurus, in assays involving preincubation of venom and antivenom. when the intraperitoneal route of injection was utilized, polyvalent (crotalinae) antivenom was effective in the neutralization of the venoms of crotalus atrox, crotalus ... | 2003 | 12782085 |
| kallikrein-like proteinase from bushmaster snake venom. | a kallikrein-like proteinase of lachesis muta muta (bushmaster) venom, designated lv-ka, was purified by gel filtration and anion exchange chromatographies. physicochemical studies indicated that the purified enzyme is a 33 kda monomeric glycoprotein, the mr of which fell to 28 kda after deglycosylation with pngase f. approximately 77% of the protein sequence was determined by sequencing the various fragments derived from digestions with endoproteases. the partial sequence obtained suggests that ... | 2003 | 12821319 |
| studies on the biologic relationship of endotoxin and other toxic proteins. ii. enhancement of susceptibility to snake venom by endotoxin. | 1. injections of sublethal quantities of agkistrodon piscivorus venom into endotoxin-treated rabbits produces a consistent early death. 2. the endotoxin-induced hypersusceptibility state (eihs) to venom is produced by intravenous, intradermal, and intraperitoneal administration of endotoxin. the latency and duration of the eihs vary with the route of administration. 3. eihs is induced by as little as 1 gamma of endotoxin administered intravenously. although the degree of susceptibility was no gr ... | 1962 | 13916025 |
| eastern diamondback rattlesnake (crotalus adamanteus) envenomation of dogs: 31 cases (1982-2002). | the medical records of 31 dogs treated for envenomation by the eastern diamondback rattlesnake (crotalus adamanteus) were reviewed. twenty-four of 25 dogs that survived were hospitalized for an average of 4.3 days. the most common presenting signs were tachycardia, swelling/edema, depressed mentation, tachypnea, and bleeding puncture wounds. thirteen (42%) of the 31 dogs were presented with or developed cardiac arrhythmias, predominantly ventricular premature contractions. hematological disorder ... | 2005 | 15634863 |
| isolation of a new l-amino acid oxidase from crotalus durissus cascavella venom. | a novel l-amino acid oxidase (lao) (casca lao) from crotalus durissus cascavella venom was purified to a high degree of molecular homogeneity using a combination of molecular exclusion and ion-exchange chromatography system. the purified monomer of lao presented a molecular mass of 68 kda and pi estimated in 5.43, which were determined by two-dimensional electrophoresis. the 71st n-terminal amino acid sequence of the lao from crotalus durissus cascavella presented a high amino acid sequence simi ... | 2006 | 16307769 |
| in vitro antimicrobial activity of natural toxins and animal venoms tested against burkholderia pseudomallei. | burkholderia pseudomallei are the causative agent of melioidosis. increasing resistance of the disease to antibiotics is a severe problem in treatment regime and has led to intensification of the search for new drugs. antimicrobial peptides are the most ubiquitous in nature as part of the innate immune system and host defense mechanism. | 2006 | 16784542 |
| antibacterial activity of snake, scorpion and bee venoms: a comparison with purified venom phospholipase a2 enzymes. | venoms of snakes, scorpions, bees and purified venom phospholipase a(2) (pla(2)) enzymes were examined to evaluate the antibacterial activity of purified venom enzymes as compared with that of the crude venoms. | 2007 | 17309613 |
| neurotropic effects of venoms and other factors that promote prey acquisition. | mammals envenomed by either the eastern diamondback rattlesnake (crotalus adamanteus) or the cottonmouth (agkistrodon piscivorus piscivorus) exhibit an immediate but transitory pupillar contraction, a parasympathomimetic effect mediated through the ciliary ganglion that can be prevented by a retrobulbar injection of anesthetic. the venom of the cottonmouth injected into the lymph spaces of the frog (rana pipiens) produces an immediate and total collapse of the lung sacs. applied locally to the s ... | 2007 | 17620305 |
| fatality in a case of envenomation by crotalus adamanteus initially successfully treated with polyvalent ovine antivenom followed by recurrence of defibrinogenation syndrome. | recurrences of clinical or laboratory manifestations of north american pit viper envenomation may happen despite control of the envenomation syndrome by prompt and adequate antivenom therapy. recurrences of coagulopathy in victims of eastern diamondback rattlesnake envenomation are generally regarded as benign. the vast majority suffer no actual bleeding despite florid coagulation laboratory abnormalities due to selective defibrinogenation. | 2008 | 18821492 |
| an experimental glomerular lesion caused by venom (crotalus adamanteus). | the venom of crotalus adamanteus when administered intravenously to rabbits in properly graded doses causes lesions of the glomerulus of tile kidney which may be either hemorrhagic or exudative in character. both types of lesion are usually associated but either one or the other may predominate. the hemorrhagic lesion, which may be confined to the glomerular tuft, or, by rupture of the latter, may involve the capsular space, is a peculiar localization of the hemorrhage so common in other parts o ... | 1909 | 19867264 |
| the effect of different snake venoms and anti-venoms on thrombin clotting time in human plasma. | crotaline snake species, or pit vipers, are distributed throughout asia and america. while much is known about the clinical effect of these snake venoms, there is a lack of evidence related to the various anti-venoms available and their effectiveness in reversing the effect of different venoms. | 2010 | 19922984 |
| a localizing circumferential compression device delayed death after artificial eastern diamondback rattlesnake envenomation to the torso of an animal model in a pilot study. | nearly all prior studies to delay onset of systemic toxicity and death after snake bite use a model of distal extremity envenomation. in the first of a series of planned studies using snake venoms with different toxicity profiles, the application of a novel device in a new model of torso envenomation in the setting of eastern coral snake (micrurus fulvius) venom (a potent neurotoxin) envenomation showed promise by delaying systemic intoxication. in this pilot study, we investigated this novel lo ... | 2010 | 20349164 |