| effects induced by bothropstoxin, a component from bothrops jararacussu snake venom, on mouse and chick muscle preparations. | bothropstoxin, a 13,700 mol. wt myotoxic phospholipase homologue isolated from the venom of bothrops jararacussu and devoid of pla2, proteolytic or hemolytic activities, inhibited muscle twitch tension, evoked either directly or indirectly through stimulation of the motor nerve in the mouse phrenic-diaphragm preparations. the compound action potential of the muscle was also abolished with a similar time course. in addition, the toxin (0.7 mm) evoked membrane depolarization which was inhibited in ... | 1992 | 1440626 |
| a new bradykinin-potentiating peptide (peptide p) isolated from the venom of bothrops jararacussu (jararacuçu tapete, urutu dourado). | several bradykinin potentiators were identified in the venom of bothrops jararacussu by chromatographic techniques and biological assays. one of them which was isolated inhibited the angiotensin-converting enzyme in vitro and potentiated the bradykinin-induced lowering of the arterial pressure in the rat. | 1992 | 1595077 |
| biologically active peptides from bothrops jararacussu venom. | the venom of the brazilian snake bothrops jararacussu, was found to contain peptides capable of potentiating the smooth muscle contracting activity of bradykinin (bk). chromatographic separation on sephadex g-25 and sephadex g-10 respectively, yielded an active peptide which at a concentration of 0.6 micrograms/ml doubled the effect of a single dose of bk on the isolated guinea-pig ileum. hplc chromatography showed this material to contain one major and 4 minor components. the active peptide was ... | 1992 | 1609644 |
| immunological studies with the venom of the scorpion tityus serrulatus. | 1. we describe a "sandwich" enzyme-linked immunosorbent assay (elisa) sensitive to quantities of scorpion (tityus serrulatus) venom (tsv) in the range of 1-3 ng/ml sample. 2. cross-reactivity with the venom from the rattlesnake crotalus durissus terrificus and with venoms from several snakes of the bothrops genus was detected only at concentrations higher than 1 microgram/ml sample. 3. a conventional elisa is also described for the detection of antibodies against tsv. 4. analysis by western blot ... | 1991 | 1823231 |
| [hemolytic activity of venoms from snakes of the genera bothrop, lachesis, crotalus, and micrurus (serpentes: viperidae and elapidae]. | hemolytic activity of eight peruvian snake venoms from the families viperidae and elapidae (bothrops atrox, b. pictus, b. hyoprorus, b. bilineatus, b. neuwedii, lachesis m. muta, crotalus d. terrificus, micrurus tschudi), and three brazilian viperids (b. jararacussu, b. alternatus and c. d. collilineatus) is described. none of the venoms caused direct lysis on washed human erythrocytes. however, all of them caused indirect hemolysis provided that the incubation medium contains an exogenous sourc ... | 1991 | 1844159 |
| cross-neutralization on the histamine-releasing activity of snake venoms. | this paper investigates the neutralizing effect of crotalic and bothropic antivenoms on the histamine-releasing activity of three different brazilian snake venoms (crotalus durissus terrificus, bothrops jararacussu and bothrops alternatus). this relative histamine-releasing activity was determined on peritoneal mixed cells of rats. c. d. terrificus venom was the most efficient histamine-releasing agent (ed50 = 1.25 micrograms/ml) followed by b. jararacussu (ed50 = 1.97 ug/ml) and b. alternatus ( ... | 1989 | 2485182 |
| muscle regeneration induced by snake venom. a histological and histochemical study. | this report describes the regeneration pattern of anterior tibial muscle of the rat after the inoculation of the snake venom of bothrops jararacussu. the results show that this regeneration pattern is rather similar to the pattern described in other experimental models. three days after the injection, three differentiated areas are established: a peripheric one of surviving fibres, a second one called myogenic area, and the last one, more internal, made of necrotic fibres that are phagocytized b ... | 1989 | 2485197 |
| differential proteolytic activation of factor viii-von willebrand factor complex by thrombin. | blood coagulation factor viii (fviii) is a plasma protein that is decreased or absent in hemophilia a. it is isolated as a mixture of heterodimers that contain a variably sized heavy chain and a common light chain. thrombin catalyzes the activation of fviii in a reaction that is associated with cleavages in both types of chain. we isolated a serine protease from bothrops jararacussu snake venom that catalyzes thrombin-like heavy-chain cleavage but not light-chain cleavage in porcine fviii as jud ... | 1989 | 2505252 |
| release of creatine kinase from skeletal muscles by bothrops venoms: heparin potentiation of inhibition by antivenin. | the glycosaminoglycan, heparin (50 micrograms/ml) inhibited the increase in creatine kinase (ck) released from rat extensor digitorum longus (edl) muscles exposed to bothrops jararaca venom (150 micrograms/ml). heparin (2 micrograms/ml) and polyvalent antivenin (0.5 microliter/ml) did not affect the increase in ck release induced by exposure of the muscles to 50 micrograms/ml b. jararacussu venom. simultaneous exposure of the muscles to venom plus heparin (2 micrograms/ml) plus antivenin (0.5 or ... | 1988 | 3228636 |
| release of sarcoplasmic enzymes from skeletal muscle by bothrops jararacussu venom: antagonism by heparin and by the serum of south american marsupials. | the venom of b. jararacussu induced a time- and dose-dependent (2-100 micrograms/ml) increase in the rate of release of sarcoplasmic enzymes (ck and ldh) from isolated rat and frog muscles. this effect, which we attribute to sarcolemmal damage by the venom, persisted in a ca2+-free media, suggesting that phospholipase a activity was not required. the venom-induced enzyme release from the isolated muscles was reversibly inhibited by the sera (1-10 microliters/ml) of the marsupials didelphis marsu ... | 1988 | 3347934 |
| interaction of bothrops venoms and antivenin on the release of creatine kinase from skeletal muscle. | a polyvalent antivenin (5 microliter/ml) inhibited the increase in creatine kinase (ck) release from rat extensor digitorum longus muscles exposed to the venoms of b. jararacussu (20 micrograms/ml) or b. jararaca (150 micrograms/ml). the increase in plasma ck activity induced by intramuscular injection of b. jararacussu venom (2.5 micrograms/g) into mice was reduced by pretreatment with antivenin and was abolished by preincubation of the venom with the antivenin. changes in ck release from isola ... | 1987 | 3455262 |
| inhibition of the myotoxic and hemorrhagic activities of crotalid venoms by eclipta prostrata (asteraceae) extracts and constituents. | the antimyotoxic and antihemorrhagic effects of eclipta prostrata (ep) and three of its constituents (wedelolactone, we; stigmaterol, st; and sitosterol, si) were investigated. the myotoxicity of crotalid venoms (bothrops jararaca, bothrops jararacussu and lachesis muta), purified myotoxins (bothropstoxin, bthtx; bothropasin; and crotoxin), and polylysine was quantified in vitro by the release rate of creatine kinase (ck) from rat or mouse extensor digitorum muscles, and in vivo by the plasma ck ... | 1994 | 8079371 |
| 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 |
| purification and characterization of a fibrinogen-clotting enzyme from the venom of jararacuçu (bothrops jararacussu). | a clotting enzyme of the venom of bothrops jararacussu, denoted fc-bj, was purified by gel chromatography on sephadex g-100 followed by hplc on deae-5pw-pak and gel filtration on sephacryl s-200hr. the enzyme was identified as an acidic glycoprotein which probably consists of a single polypeptide chain with isoelectric point values in the range 3.3-4.4 and containing approx. 19% carbohydrates. on polyacrylamide gel electrophoresis (page) at ph 8.3, the enzyme presented a diffuse protein band. on ... | 1996 | 8843581 |
| isolation and characterization of a myotoxic phospholipase a2 from the venom of the arboreal snake bothriechis (bothrops) schlegelii from costa rica. | a new myotoxic phospholipase a2 was isolated from the venom of the arboreal snake bothriechis schlegelii (formerly bothrops schlegelii) from costa rica, by ion-exchange chromatography on cm-sephadex. b. schlegelii myotoxin i is a basic protein (pi > 9.3) with a subunit molecular weight of 15 kda, which migrates as a dimer in sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreducing conditions. this myotoxin is recognized by antibodies generated against bothrops asper myotoxin i ... | 1997 | 9056257 |
| snake bites by the jararacuçu (bothrops jararacussu): clinicopathological studies of 29 proven cases in são paulo state, brazil. | the jararacuçu, one of the most dreaded snakes of brazil, southern bolivia, paraguay and northeastern argentina, is a heavily-built pit viper which may grow to a length of 2.2 m. up to 1000 mg (dry weight) of highly-lethal venom may be milked from its venom glands on a single occasion. it has accounted for 0.8% to 10% of series of snake bites in são paulo state, brazil. we examined 29 cases of proven jararacuçu bites recruited over a 20-year period in two são paulo hospitals. severe signs of loc ... | 1997 | 9205667 |
| inhibition of proteases, myotoxins and phospholipases a2 from bothrops venoms by the heteromeric protein complex of didelphis albiventris opossum serum. | the antibothropic complex (abc) from opossum (species didelphis albiventris) serum was purified by chromatography on deae-sephacel. it showed an acidic character and two polypeptide chains of ca. 45 kda and 48 kda, respectively. lyophilized opossum serum or the abc (100 micrograms), as well as ethylenediamine tetraacetate (0.25 mumoles) were able to completely neutralise the hemorrhagic effect of 50 micrograms of the desiccated venoms of bothrops moojeni, bothrops pirajai and bothrops jararacuss ... | 1997 | 9415818 |
| mast cell degranulation induced by two phospholipase a2 homologues: dissociation between enzymatic and biological activities. | bothropstoxin-i and bothropstoxin-ii are phospholipase a2 homologues isolated from bothrops jararacussu snake venom. the former is devoid of phospholipase a2 activity whereas the latter has very low enzymatic activity. in this study, we have investigated the in vivo (rat paw and skin oedema) and in vitro (mast cell degranulation) inflammatory effects caused by bothropstoxin-i and bothropstoxin-ii. bothropstoxin-i (25-100 microg/paw) and bothropstoxin-ii (12.5-50 microg/paw) caused dose-dependent ... | 1998 | 9570475 |
| [hemorrhage induced by snake venoms in argentina]. | mice of 18 and 20 g were injected intradermally with 0.1 ml of serial dilution of venom in saline solution 0.9 buffered ph 7.2. groups of 4 animal were formed, they were sacrificed 2 hours after inoculation. skin of every mouse was put out, and the haemorrhagic area was measured bothrops alternatus, bothrops jararaca, bothrops jararacussu and bothrops neuwiedii venoms were used. crotalus durissus terrificus did not show any haemorrhagic activity. | 1997 | 9580123 |
| [hemorrhagic and edema-forming activity and histologic changes in the mouse footpad induced by venoms from argentinian bothrops and crotalus genuses]. | hemorrhagic, oedema-forming activities and histopathological alterations in the mouse footpad induced by bothrops and crotalus snake venoms from argentina. hemorrhagic and oedema-forming activities of various bothrops and crotalus snake venoms from argentina were studied, together with histological alterations in the mouse footpad. the highest oedema-forming activity was found in the venom of b. jararaca, followed by b. jararacussu, b. neuwiedii diporus, b. alternatus, and crotalus durissus terr ... | 1998 | 9690783 |
| cross-reactivity and heterologous neutralization of crotaline antivenoms used in argentina. | the immunochemical cross-reactivity and neutralizing capacity of four crotalinae antivenoms consisting in equine f(ab')2 fragments and available in argentina (bothropic bivalent, against bothrops alternatus and b. neuwiedii venoms; bothropic tetravalent, against b. alternatus, b. neuwiedii; b. jararaca and b. jararacussu venoms; bothropic crotalic trivalent, against b. alternatus, b. neuwiedii and crotalus (c.) durissus terrificus venoms and anticrotalic against c. d. terrificus venom) were stud ... | 1998 | 9690795 |
| neutralizing potency of horse antibothropic antivenom. correlation between in vivo and in vitro methods. | the correlation coefficients between in vivo neutralization of lethal toxicity (ed50), neutralization of the hemolytic activity (pla2) and levels of antibodies measured by elisa, was investigated to test the potency of horse anti-bothropic antivenom. twenty six horses were hyperimmunized with bothrops venoms (b. alternatus, b. jararaca, b. jararacussu, b. neuwiedii and b. moojeni). to set up an indirect elisa, for neutralization of pla2 activity and for determination of ed50 in swiss mice, the w ... | 1998 | 9723841 |
| a study on the venom yield of venomous snake species from argentina. | a study on the venom yield of snakes from argentina over a three year period was carried out on adult specimens of bothrops alternatus (n = 74); bothrops neuwiedii (n = 127); bothrops ammodytoides (n = 30); bothrops moojeni (n = 14); bothrops jararaca (n = 14); b. jararacussu (n = 6); crotalus durissus terrificus (n = 120) and micrurus spp. (n = 6) as well as with 12 specimens of newborn c. d. terrificus kept in captivity. while for each species there was a positive correlation between venom yie ... | 1998 | 9839679 |
| amino acid sequence of piratoxin-i, a myotoxin from bothrops pirajai snake venom, and its biological activity after alkylation with p-bromophenacyl bromide. | the complete sequence of the 121 amino acid residues of piratoxin-i (prtx-i), a phospholipase a2 (pla2)-like myotoxin from bothrops pirajai snake (bahia jararacussu) venom, is reported. from the sequence, an m, of 13,825 and an approximate pi of 8.3 were calculated. prtx-i shows a high sequence homology with lys-49 myotoxins from other bothropic (approximately 95%) and nonbothropic (approximately 80%) venoms, but only 70-75% homology when aligned with the catalytically active asp-49 pla2s. when ... | 1998 | 9853687 |
| isolation and characterization of an arginine ester hydrolase from bothrops jararacussu venom which induces contractions of the isolated rat uterus. | the isolation and partial characterization of a serine protease with arginine ester hydrolase activity from bothrops jararacussu snake venom are described. the purification procedure consisted of a gel filtration of the crude venom on sephadex g-75 followed by an ion-exchange chromatography of the active fraction on deae-cellulose and a rechromatography on bio-rex 70 resin. the esterase fraction (di-iii), m(r) = 25,000 by sds-page, showed proteolytic activity on fibrinogen and casein. after 2 hr ... | 1999 | 10319423 |
| identification of bothrojaracin-like proteins in snake venoms from bothrops species and lachesis muta. | bothrojaracin, a 27 kda protein isolated from bothrops jararaca venom, forms a non-covalent complex with thrombin, thus blocking its activity. we have previously identified a bothrojaracin-like protein in b. alternatus venom [castro, h.c., dutra, d.l.s., oliveira-carvalho, a.l., zingali, r.b., 1998. bothroalternin, an inhibitor of thrombin from the venom of bothrops alternatus. toxicon 36, 1903-1912]. in this report, we have examined snake venoms from six different bothrops species (b. atrox, b. ... | 1999 | 10414865 |
| [cross neutralization of bothrops jararacussu venom by heterologous antivenoms]. | we have studied the immunochemical cross-reactivity and cross-neutralization of the lethal potency, hemorrhagic, necrotizing, procoagulant and (indirect) hemolytic activities of bothrops jararacussu venom by the standard antivenoms produced in argentina. these antivenoms are horse immunoglobulin f (ab')2 fragments from animals immunized with 1) crotalus durissus terrificus venom (monovalent anticrotalic antivenom); 2) bothrops alternatus and b. neuwiedii venoms (bivalent botropic antivenom); 3) ... | 1999 | 10451561 |
| the effect of a lectin from the venom of the snake, bothrops jararacussu, on tumor cell proliferation. | lectins have been used extensively as histochemical probes to describe changes in tumor cell surface and are known to influence the growth of cancer cells. in this study, we determined the effect of a lectin from the venom of bothrops jararacussu (bjcul) on the proliferation of a number of established human cancer cell lines. the growth of eight cancer cell lines was inhibited in a dose-related manner in the presence of bjcul lectin. this lectin was most potent as an inhibitor of growth in renal ... | 1999 | 10628348 |
| horse igg isotypes and cross-neutralization of two snake antivenoms produced in brazil and costa rica. | horse igg isotypes and cross-neutralization of two snake antivenoms produced in brazil and costa rica. toxicon 000-000. this work compared the specificity, elisa titers and igg subclass content of the polyvalent antivenom (anti-bothrops asper, crotalus durissus durissus and lachesis muta stenophrys) of instituto clodomiro picado (costa rica) and the bothropic antivenom (anti-bothrops jararaca, b. jararacussu, b. moojeni, b. neuwiedi and b. alternatus) of instituto butantan (brazil). the role of ... | 2000 | 10673156 |
| leucocyte recruitment induced by type ii phospholipases a(2) into the rat pleural cavity. | bothropstoxin-i (bthtx-i) and bothropstoxin-ii (bthtx-ii) are lys-49 and asp-49 phospholipases a(2) (pla(2)s), respectively, isolated from bothrops jararacussu venom. piratoxin-i (prtx-i) is a lys-49 pla(2) isolated from bothrops pirajai venom. in this study, the ability of bthtx-i, bthtx-ii and prtx-i to recruit leucocytes into the rat pleural cavity and potential mechanisms underlying this effect were investigated. intrapleural injection of either bthtx-i or prtx-i (10-100 microg/cavity each) ... | 2000 | 10858516 |
| structural and functional characterization of bnsp-7, a lys49 myotoxic phospholipase a(2) homologue from bothrops neuwiedi pauloensis venom. | bnsp-7, a lys49 myotoxic phospholipase a(2) homologue from bothrops neuwiedi pauloensis venom, was structurally and functionally characterized. several biological activities were assayed and compared with those of the chemically modified toxin involving specific amino acid residues. the cdna produced from the total rna by rt-pcr contained approximately 400 bp which codified its 121 amino acid residues with a calculated pi and molecular weight of 8.9 and 13,727, respectively. its amino acid seque ... | 2000 | 10860537 |
| myotoxic phospholipases a(2) in bothrops snake venoms: effect of chemical modifications on the enzymatic and pharmacological properties of bothropstoxins from bothrops jararacussu. | venoms from eight bothrops spp. were fractionated by ion-exchange chromatography on cm-sepharose at ph 8.0 for the purification of myotoxins. chromatographic profiles showed differences regarding myotoxic components among these venoms. b. alternatus, b. atrox and b. jararaca venoms did not show the major basic myotoxic fractions identified in the other venoms. polyacrylamide gel electrophoresis for basic proteins also showed distinct patterns for these toxins. in vivo, all the isolated myotoxins ... | 2000 | 11018293 |
| neutralizing capacity of commercial bothropic antivenom against bothrops jararacussu venom and bothropstoxin-i. | bothrops jararacussu venom and its major toxin, bothropstoxin-i (bthtx-i), possess myotoxic and neurotoxic activities. the ability of commercial equine antivenom to neutralize these activities was studied in mouse isolated phrenic nerve-diaphragm (pnd) and extensor digitorum longus (edl) preparations by indirect stimulation (0.1 hz, 0.2 ms). the time required to produce 50% neuromuscular blockade in the pnd and edl preparations was, respectively, 70 +/- 11.5 min and 58 +/- 8 min for b. jararacus ... | 2000 | 11102906 |
| refolding and purification of bothropstoxin-i, a lys49-phospholipase a2 homologue, expressed as inclusion bodies in escherichia coli. | hydrolysis of phospholipids by group ii phospholipase a2 enzymes involves a nucleophilic attack on the sn-2 ester bond by the his48 residue and stabilization of the reaction intermediate by a ca2+ ion cofactor bound to the asp49 residue in the protein active site region. bothropstoxin-i (bthtx-i) is a pla(2) variant present in the venom of the snake bothrops jararacussu which shows a asp49 to lys substitution and which lacks hydrolytic activity yet damages artificial membranes by a noncatalytic ... | 2001 | 11162398 |
| effect of bjcul (a lectin from the venom of the snake bothrops jararacussu) on adhesion and growth of tumor and endothelial cells. | lectins are polyvalent carbohydrate-binding proteins of non-immune origin. recently, we have isolated and characterized a lectin from the venom of the snake bothrops jararacussu. this lectin (bjcul) has been shown to bind to lactose moieties and induce agglutination of erythrocytes. in the present work, we observed that cells from human metastatic breast cancer (mda-mb-435) and human ovarian carcinoma (ovcar-5) cell lines adhere, although weakly, to bjcul. however, bjcul did not inhibit adhesion ... | 2001 | 11478954 |
| neutralization of the pharmacological effects of bothropstoxin-i from bothrops jararacussu (jararacuçu) venom by crotoxin antiserum and heparin. | bothropstoxin-i (bthtx-i), the principal myotoxin of bothrops jararacussu venom, is devoid of phospholipase a(2) (pla(2)) activity but capable of blocking neuromuscular transmission in mouse nerve-muscle preparations. in this study, the ability of crotoxin antiserum and heparin in preventing the neurotoxic and myotoxic effects of bthtx-i was investigated. phrenic nerve-diaphragm preparations (pnd) stimulated indirectly with supramaximal stimuli (0.2 ms, 0.1 hz) were incubated with bthtx-i (20 mi ... | 2001 | 11478955 |
| determination of the neutralizing potency of horse antibothropic and anticrotalic antivenoms in blood samples collected on filter paper. | the correlation coefficients between in vivo neutralization of lethal toxicity (ed(50)) and levels of antibodies measured by enzyme-linked immunosorbent assay (elisa) in blood samples collected on filter paper were investigated to test the potency of horse antibothropic and anticrotalic antivenoms. sixteen horses were hyperimmunized with bothrops venom (50% from b. jararaca and 12.5% each from b. alternatus, b. jararacussu, b. neuwiedii and b. moojeni) and 12 horses with crotalus durissus terrif ... | 2001 | 11478970 |
| isolation and enzymatic characterization of a basic phospholipase a2 from bothrops jararacussu snake venom. | a novel basic phospholipase a2 (pla2) isoform was isolated from bothrops jararacussu snake venom and partially characterized. the venom was fractionated by hplc ion-exchange chromatography in ammonium bicarbonate buffer, followed by reverse-phase hplc to yield the protein bj iv. tricine sds-page in the presence or absence of dithiothreitol showed that bj iv had a molecular mass of 15 and 30 kda, respectively. this enzyme was able to form multimeric complexes (30, 45, and 60 kda). amino acid anal ... | 2001 | 11565904 |
| the renal effects of bothrops jararacussu venom and the role of pla(2) and paf blockers. | the most common complication in the lethal cases of ophidian bites in brazil is acute renal failure, but its pathogenesis is obscure. the effects of bothrops jararacussu venom (3, 10 and 30 microg/ml) were examined using the isolated perfused kidney from wistar rats. dexamethasone, and web 2086, a triazolobenzodiazepine substance, which is a platelet activating factor receptor antagonist, were tested for a possible blockade of the renal effects in the presence of 10 microg/ml of venom. the most ... | 2001 | 11600146 |
| active-site mutagenesis of a lys49-phospholipase a2: biological and membrane-disrupting activities in the absence of catalysis. | bothropstoxin-i (bthtx-i) is a myotoxic phospholipase a(2) variant present in the venom of bothrops jararacussu, in which the asp(49) residue is replaced with a lysine, which damages artificial membranes by a ca(2+)-independent mechanism. wild-type bthtx-i and the mutants lys(49)-->asp, his(48)-->gln and lys(122)-->ala were expressed in escherichia coli bl21(de3) cells, and the hydrolytic, myotoxic and membrane-damaging activities of the recombinant proteins were compared with native bthtx-i pur ... | 2002 | 11829743 |
| primary structure characterization of bothrops jararacussu snake venom lectin. | the complete amino acid sequence of the lectin from bothrops jararacussu snake venom (bjcul) is reported. the sequence was determined by edman degradation and amino acid analysis of the s-carboxymethylated bjcul derivative (rc-bjcul) and from its peptides originated from enzymatic digestion. the sequence of amino acid residues showed that this lectin displays the invariant amino acid residues characterized in c-type lectins. amino acids analysis revealed a high content of acidic amino acids and ... | 2002 | 11902666 |
| mn(2+) ions reduce the enzymatic and pharmacological activities of bothropstoxin-i, a myotoxic lys49 phospholipase a(2) homologue from bothrops jararacussu snake venom. | bothropstoxin-i (bthtx-i), a myotoxic lys49 phospholipase a(2) (pla(2)) homologue isolated from bothrops jararacussu snake venom, causes a range of biological effects, including myonecrosis, mouse paw edema, irreversible neuromuscular blockade and lysis of cell cultures. among eight divalent cations assayed, mn(2+) was the most effective in reducing mouse paw edema induced by bthtx-i (25 microg). preincubating bthtx-i with mn(2+) (1.0mm) reduced mouse paw edema by 70% and myotoxicity by 60% in m ... | 2002 | 11943597 |
| 60co gamma irradiation prevents bothrops jararacussu venom neurotoxicity and myotoxicity in isolated mouse neuromuscular junction. | the ability of gamma radiation from 60co (2000 gy) to attenuate the toxic effects of bothrops jararacussu venom was investigated on mouse neuromuscular preparations in vitro. a comparative study between the effects of native and irradiated venoms was performed on both phrenic--diaphragm (pd) and extensor digitorum longus (edl) preparations by means of myographic, biochemical and morphological techniques. native venom (10 and 20 micro g/ml) induced a concentration--dependent paralysis of both dir ... | 2002 | 12165311 |
| structural and functional characterization of an acidic platelet aggregation inhibitor and hypotensive phospholipase a(2) from bothrops jararacussu snake venom. | an acidic (pi approximately 4.5) phospholipase a(2) (btha-i-pla(2)) was isolated from bothrops jararacussu snake venom by ion-exchange chromatography on a cm-sepharose column followed by reverse phase chromatography on an rp-hplc c-18 column. it is an approximately 13.7kda single chain asp49 pla(2) with approximately 122 amino acid residues, 7 disulfide bridges, and the following n-terminal sequence: 1slwqfgkminyvm-gesgvlqylsygcycglggqgqptdatdrccfvhdcc(51). crystals of this acidic protein diffra ... | 2002 | 12167491 |
| purification, characterization and crystallization of jararacussin-i, a fibrinogen-clotting enzyme isolated from the venom of bothrops jararacussu. | a fibrinogen-clotting enzyme, jararacussin-i, was purified from the venom of bothrops jararacussu by a combination of ion exchange chromatography using resource 15s resin and affinity chromatography using benzamidine sepharose 6b resin. jararacussin-i displays a molecular mass of 28 kda as estimated by sodium dodecyl sulphate-page and possesses an isoelectric point of 5.0. the coagulant specific activity of the enzyme was determined to be 45.8 nihu/mg using bovine fibrinogen as the substrate and ... | 2002 | 12220716 |
| acute local nerve lesions induced by bothrops jararacussu snake venom. | myonecrosis is one of the most common effects of bothrops jararacussu venom, but little is known about the action of this venom on other tissues. in this study, we used transmission electron microscopy to examine the influence of b. jararacussu venom on nerve tissue. a sublethal dose of venom (80 microg) was injected into the tibialis anterior muscle of mice which were then killed at various intervals up to 6 h after venom injection. the venom caused massive, progressive axonal damage beginning ... | 2002 | 12368118 |
| cdna sequence and molecular modeling of a nerve growth factor from bothrops jararacussu venomous gland. | the complete nucleotide sequence of a nerve growth factor precursor from bothrops jararacussu snake (bj-ngf) was determined by dna sequencing of a clone from cdna library prepared from the poly(a) + rna of the venom gland of b. jararacussu. cdna encoding bj-ngf precursor contained 723 bp in length, which encoded a prepro-ngf molecule with 241 amino acid residues. the mature bj-ngf molecule was composed of 118 amino acid residues with theoretical pi and molecular weight of 8.31 and 13,537, respec ... | 2002 | 12453640 |
| structural and functional analysis of bmjmip, a phospholipase a2 myotoxin inhibitor protein from bothrops moojeni snake plasma. | a protein, which neutralizes the enzymatic, toxic, and pharmacological activities of various basic and acidic phospholipases a(2) from the venoms of bothrops moojeni, bothrops pirajai, and bothrops jararacussu, was isolated from b. moojeni snake plasma by affinity chromatography using immobilized myotoxins on sepharose gel. biochemical characterization of this myotoxin inhibitor protein (bmjmip) showed it to be an oligomeric glycoprotein with a m(r) of 23,000-25,000 for the monomeric subunit. bm ... | 2003 | 12604331 |
| spectroscopic analysis of the stability of bothrops myotoxic phospholipases a2 to guanidine and urea denaturation. | spectrophotometric profiles representing the unfolding induced by guanidine on bothrops moojeni myotoxins-i (mjtx-i) and ii (mjtx-ii), bothrops jararacussu bothropstoxin-i (bthtx-i) and bothrops pirajai piratoxin-i (prtx-i) were obtained and compared with those obtained with bovine ribonuclease a (rnase) and trypsin. the molar (epsilon(1m)) and percent (epsilon(1%)) extinction coefficients were determined for the four myotoxins as well as for rnase and trypsin as reference parameters. these coef ... | 2003 | 12625831 |
| serological analysis of venoms and antivenins. | the immunological relationship between the venoms of six species of the snake genus bothrops (alternata, atrox, cotiara, jararaca, jararacussu, neuwiedii) was investigated by assay against the corresponding species-specific antivenins in more than 11,000 intravenous and subcutaneous mouse tests. the observations were statistically analysed after the probit method.both ways of antivenin assay gave numerically identical results, within the limits of error, in the majority of the tests. the width o ... | 1955 | 13240449 |
| antagonism of myotoxic and paralyzing activities of bothropstoxin-i by suramin. | polyanionic substances are known to inhibit the myotoxic effects of some crotalide snake venoms. bothropstoxin-i (bthtx-i), a basic lys49 phospholipase (pla2) homologue from bothrops jararacussu venom, besides inducing muscle damage, also promotes the blockade of both directly and indirectly evoked contractions in mouse neuromuscular preparation. in this work, we evaluated the ability of suramin, a polysulfonated naphtylurea derivative, to antagonize the myotoxic and the paralyzing activities of ... | 2003 | 14505937 |
| analysis of bothrops jararacussu venomous gland transcriptome focusing on structural and functional aspects: i--gene expression profile of highly expressed phospholipases a2. | snake venom glands are a rich source of bioactive molecules such as peptides, proteins and enzymes that show important pharmacological activity leading to in local and systemic effects as pain, edema, bleeding and muscle necrosis. most studies on pharmacologically active peptides and proteins from snake venoms have been concerned with isolation and structure elucidation through methods of classical biochemistry. as an attempt to examine the transcripts expressed in the venom gland of bothrops ja ... | 2004 | 15134836 |
| cloning, expression, and structural analysis of recombinant bjcul, a c-type lectin from the bothrops jararacussu snake venom. | the lactose-binding lectin from bothrops jararacussu venom (bjcul) is a homodimer belonging to group vii of the c-type animal lectins. bjcul has also been shown to serve as an interesting tool for combating tumor progression by inhibiting cancer and endothelial cell growth. however, detailed structural studies of bjcul and its biological mechanisms of cytotoxicity are yet to be reported, perhaps because of the non-availability of recombinant proteins in necessary quantities. intending to increas ... | 2004 | 15135412 |
| topology of the substrate-binding site of a lys49-phospholipase a2 influences ca2+-independent membrane-damaging activity. | bthtx-i (bothropstoxin-i) is a myotoxic lys49-pla2 (phospholipase a2 with lys49) isolated from bothrops jararacussu venom, which damages liposome membranes by a ca2+-independent mechanism. the highly conserved phe5/ala102/phe106 motif in the hydrophobic substrate-binding site of the asp49-pla2s is substituted by leu5/val102/leu106 in the lys49-pla2s. the leu5/val102/leu106 triad in bthtx-i was sequentially mutated via all single- and double-mutant combinations to the phe5/ala102/phe106 mutant. a ... | 2004 | 15147240 |
| cloning and identification of a complete cdna coding for a bactericidal and antitumoral acidic phospholipase a2 from bothrops jararacussu venom. | in order to better understand the function of acidic phospholipases a2 (pla2s) from snake venoms, expressed sequence tags (ests) that code for acidic pla2s were isolated from a cdna library prepared from the poly(a)+ rna of venomous glands of bothrops jararacussu. the complete nucleotide sequence (366 bp), named boju-iii, encodes the btha-i-pla2 precursor, which includes a signal peptide and the mature protein with 16 and 122 amino acid residues, respectively. multiple comparison of both the nuc ... | 2004 | 15214498 |
| a new hemorrhagic metalloprotease from bothrops jararacussu snake venom: isolation and biochemical characterization. | a hemorrhagic metalloprotease, named bjussump-i, was isolated from bothrops jararacussu snake venom by a combination of gel filtration on sephacryl s-200 (0.01 m tris-hcl, ph 7.6 buffer) and phenyl sepharose cl-4b chromatography (0.01 m tris-hcl plus 4 m nacl, ph 8.6 buffer, followed by a concentration gradient from 4 to 0 m nacl at 25 degrees c in the same buffer). bjussump-i is a 60 kda protein with a pi approximately 5.5, which induced hemorrhage after intradermal injection in mice, with a mi ... | 2004 | 15246772 |
| cloning and expression of an acidic platelet aggregation inhibitor phospholipase a2 cdna from bothrops jararacussu venom gland. | the phospholipase a2 (pla2, e.c. 3.1.1.4) superfamily is defined by enzymes that catalyze the hydrolysis of the sn-2 bond of phosphoglycerides. most pla2s from the venom of bothrops species are basic proteins, which have been well characterized both structurally and functionally, however, little is known about acidic pla2s from this venom. nevertheless, it has been demonstrated that they are non-toxic, with high catalytic and hypotensive activities and show the ability to inhibit platelet aggreg ... | 2004 | 15294287 |
| comparison of the neurotoxic and myotoxic effects of brazilian bothrops venoms and their neutralization by commercial antivenom. | the venoms of some bothrops species produce neuromuscular blockade in avian and mammalian nerve-muscle preparations in vitro. in this study, we compared the neuromuscular activities (myotoxicity and neurotoxicity) of venoms from several brazilian species of bothrops (b. jararaca, b. jararacussu, b. moojeni, b. erythromelas and b. neuwiedi) in chick isolated biventer cervicis muscle preparations and examined their neutralization by commercial antivenom. all of the venoms (50-200 microg/ml, n = 3 ... | 2004 | 15302532 |
| the presynaptic activity of bothropstoxin-i, a myotoxin from bothrops jararacussu snake venom. | bothropstoxin-i from bothrops jararacussu snake venom is a lysine-49 phospholipase a(2) with myotoxic and neurotoxic activities. in this study, we used mouse phrenic nerve-diaphragm preparations in the absence and presence of manganese (mn(2+)), a presynaptic blocker, to investigate a possible presynaptic action of bothropstoxin-i. at concentrations of 0.9 mm and 1.8 mm, mn(2+) produced 50% neuromuscular blockade in less than 4 min., which was spontaneously reversible at the lower concentration. ... | 2004 | 15504153 |
| in vitro cytotoxicity of epigallocatechin gallate and tea extracts to cancerous and normal cells from the human oral cavity. | this study compared the in vitro responses of malignant and normal cells from the human oral cavity to tea extracts and to its main polyphenolic component, (-)-epigallocatechin gallate (egcg). the antiproliferative effects of tea polyphenolic extracts and egcg were more pronounced towards immortalized, tumourigenic (cal27, hsc-2, and hsg(1)) and non-tumourigenic (s-g) cells than towards normal (gn56 and hgf-1) fibroblasts and green tea was more toxic than black tea. as the addition of tea extrac ... | 2004 | 15504155 |
| signal transduction pathways involved in the platelet aggregation induced by a d-49 phospholipase a2 isolated from bothrops jararacussu snake venom. | bothropstoxin-ii (bthtx-ii), an asp-49 phospholipase a(2) (d-pla(2)) isolated from bothrops jararacussu snake venom is able to induce platelet aggregation in a concentration-dependent manner. this effect was not due to the release of adp from platelets since the aggregation was not suppressed by adp scavenger systems. pmsf and ppack were unable to inhibit bthtx-ii-induced platelet aggregation. thus, a thrombin-like proaggregating activity of bthtx-ii can be excluded as its mechanism of action. o ... | 2004 | 15556284 |
| inhibition of the myotoxic activity of bothrops jararacussu venom and its two major myotoxins, bthtx-i and bthtx-ii, by the aqueous extract of tabernaemontana catharinensis a. dc. (apocynaceae). | partial neutralization of the myotoxic effect of bothrops jararacussu venom (bv) and two of its myotoxins [bothropstoxin-i (bthtx-i), catalytically inactive, and ii (bthtx-ii), showing low pla2 activity], by the lyophilized aqueous extract of tabernaemontana catharinensis (ae), was studied in rat isolated soleus muscle preparations (in vitro) and through i.m. injection in the gastrocnemius muscle (in vivo) by determination of creatine kinase (ck) activity and histopathological analysis. incubati ... | 2005 | 15693719 |
| influence of temperature upon paralyzing and myotoxic effects of bothropstoxin-i on mouse neuromuscular preparations. | bothropstoxin-i (bthtx-i), from b. jararacussu venom, is a phospholipase a2 (pla2) homologue devoid of enzymatic activity. besides inducing severe myonecrosis, bthtx-i promotes paralysis of both directly and indirectly evoked contractions in isolated neuromuscular preparations. we applied an experimental paradigm in order to characterize the steps involved in the toxic effects of bthtx-i on mouse neuromuscular junction. myotoxicity was assessed by microscopic analysis of extensor digitorum longu ... | 2005 | 15698581 |
| anticoagulant and antifibrinogenolytic properties of the aqueous extract from bauhinia forficata against snake venoms. | the aqueous extract from aerial parts of bauhinia forficata was able to neutralize the clotting activity induced by bothrops and crotalus crude venoms. the clotting time, upon human plasma, induced by b. moojeni venom was significantly prolonged. clotting and fibrinogenolytic activities induced by isolated thrombin-like enzyme from bothrops jararacussu were totally inhibited after incubation at different ratios. the extract was not able to neutralize the hemorrhagic activity induced by an bothro ... | 2005 | 15763387 |
| rosmarinic acid, a new snake venom phospholipase a2 inhibitor from cordia verbenacea (boraginaceae): antiserum action potentiation and molecular interaction. | many plants are used in traditional medicine as active agents against various effects induced by snakebite. the methanolic extract from cordia verbenacea (cv) significantly inhibited paw edema induced by bothrops jararacussu snake venom and by its main basic phospholipase a2 homologs, namely bothropstoxins i and ii (bthtxs). the active component was isolated by chromatography on sephadex lh-20 and by rp-hplc on a c18 column and identified as rosmarinic acid (cv-ra). rosmarinic acid is an ester o ... | 2005 | 15992846 |
| antihemorrhagic, antinucleolytic and other antiophidian properties of the aqueous extract from pentaclethra macroloba. | several brazilian plants have been utilized in folk medicine as active agents against various effects induced by snake venoms. the inhabitants of the amazon region use, among others, the macerated bark of a plant popularly named "pracaxi" (pentaclethra macroloba willd) to combat these effects. we report now the antihemorrhagic properties against snake venoms of the aqueous extract of pentaclethra macroloba (epema). epema exhibited full inhibition of hemorrhagic and nucleolytic activities induced ... | 2005 | 16054531 |
| antiophidian properties of the aqueous extract of mikania glomerata. | aqueous extracts, prepared from dried or fresh roots, stems or leaves of mikania glomerata, a plant found in mata atlântica in southeastern brazil, were able to efficiently neutralize different toxic, pharmacological, and enzymatic effects induced by venoms from bothrops and crotalus snakes. phospholipase a(2) activity and the edema induced by crotalus durissus terrificus venom were inhibited around 100 and approximately 40%, respectively, although this inhibition was only partial for bothrops v ... | 2005 | 16084045 |
| renal and antibacterial effects induced by myotoxin i and ii isolated from bothrops jararacussu venom. | bothrops jararacussu myotoxin i (bthtx-i; lys 49) and ii (bthtx-ii; asp 49) were purified by ion-exchange chromatography and reverse phase hplc. in this work we used the isolated perfused rat kidney method to evaluate the renal effects of b. jararacussu myotoxins i (lys49 pla2) and ii (asp49 pla2) and their possible blockage by indomethacin. bthtx-i (5 microg/ml) and bthtx-ii (5 microg/ml) increased perfusion pressure (pp; ct120=110.28+/-3.70 mmhg; bthtx i=171.28+/-6.30*mmhg; bthtx ii=175.50+/-7 ... | 2005 | 16115661 |
| cross-neutralization of the neurotoxicity of crotalus durissus terrificus and bothrops jararacussu venoms by antisera against crotoxin and phospholipase a2 from crotalus durissus cascavella venom. | we have previously demonstrated that rabbit antisera raised against crotoxin from crotalus durissus cascavella venom (cdc-crotoxin) and its pla2 (cdc-pla2) neutralized the neurotoxicity of this venom and its crotoxin. in this study, we examined the ability of these antisera to neutralize the neurotoxicity of crotalus durissus terrificus and bothrops jararacussu venoms and their major toxins, cdt-crotoxin and bothropstoxin-i (bthtx-i), respectively, in mouse isolated phrenic nerve-diaphragm prepa ... | 2005 | 16157360 |
| microvessel damage by b. jararacussu snake venom: pathogenesis and influence on muscle regeneration. | the loss of muscle mass consequent to poor muscle regeneration is a common sequela following the injection of bothrops jararacussu snake venom. since an intact microvasculature plays a central role in the success of muscle regeneration, the poor muscle regeneration seen after envenomation could be explained by damage to the local microvasculature. in this work, we investigated the pathogenesis of microvessel damage caused by b. jararacussu venom and its correlation with poor muscle regeneration. ... | 2005 | 16198390 |
| conceptions and first results on the electrocrystallization behaviour of ferritin. | the role of electrochemical processes on fe and cdso(4) in the crystallization of horse spleen ferritin has been investigated using the cyclic voltammetry technique. it was found that although both species exhibit important redox properties in the presence of an external applied potential, cdso(4) played a leading role not only in the nucleation process but also in the growth behaviour and morphology of ferritin crystals. | 2005 | 16301803 |
| biological activities of a lectin from bothrops jararacussu snake venom. | snake venoms contain saccharide-binding lectins. in this work, we examined the biological activities of a lectin (bjcul) purified from bothrops jararacussu snake venom by chromatography on non-derivatized sepharose 4b and sephacryl s-200 hr. the protein, a homodimer with subunits of 14.5 kda, gave a single immunoprecipitin line in immunoelectrophoresis and cross-reacted in elisa with antivenoms raised against bothrops spp. (lanceheads), micrurus spp. (coral snakes), crotalus durissus terrificus ... | 2006 | 16309723 |
| paralyzing and myotoxic effects of a recombinant bothropstoxin-i (bthtx-i) on mouse neuromuscular preparations. | as a first step to investigate the structure-function relationship of bothropstoxin-i (bthtx-i), a myotoxin from bothrops jararacussu snake venom, our group previously cloned a recombinant toxin (rbthtx-i) in escherichia coli. the aim of this work was to characterize the biological activities of this rbthtx-i (1.0 microm) in both phrenic-diaphragm and extensor digitorum longus preparations in vitro, by means of myographic and morphologic techniques. native bthtx-i (1.0 microm) was used as a stan ... | 2006 | 16410190 |
| expression of recombinant human antibody fragments capable of inhibiting the phospholipase and myotoxic activities of bothrops jararacussu venom. | phospholipases a(2) are components of bothrops venoms responsible for disruption of cell membrane integrity via hydrolysis of its phospholipids. this study used a large nonimmune human scfv library named griffin.1 (mrc, cambridge, uk) for selection of recombinant antibodies against antigens present in bothrops jararacussu venom and identification of specific antibodies able to inhibit phospholipase activity. four clones were identified as capable of inhibiting this activity in vitro. these clone ... | 2006 | 16828972 |
| determination of primary structure of two isoforms 6-1 and 6-2 pla2 d49 from bothrops jararacussu snake venom and neurotoxic characterization using in vitro neuromuscular preparation. | in this paper we reported the purification, the biological characterization and the amino acid sequence of two new isoforms basic 6-1 (bj-iv) and 6-2 (bj-v) pla(2) d49 purified from the bothrops jararacussu venom. the isoforms 6-1 and 6-2 had a sequence of amino acids of 121 amino acid residues 6-1: dlfewgqmil ketgknpfpy ygaygcycgw ggrgkpkdkd tdrccyvhdc cykkltgcpk tddrysyswl dltivcgedd pckelcecdk aiavcfrenl gtynkkyryh lkpckkadkp c and pi value 7.83 and 6-2: dlwqfgqmil ketgkipfpy ygaygcycgw ggrgg ... | 2006 | 16862457 |
| l-arginine enhances muscle regeneration after experimental envenomation by b. jararacussu: a future for nitric oxide-based therapy? | we investigated whether muscle fiber regeneration would be rescued by exogenous administration of l-arginine, the precursor of endogenous synthesis of nitric oxide. the right tibialis anterioris muscle of adult mice (n=20) was injected with 80 microg of venom. one group of mice (n=10) received drinking water containing l-arginine (3.75 mg/ml) and another group (n=10) did not receive any pharmacological treatment. two months later, muscle regeneration was evaluated by counting the total number of ... | 2006 | 16876838 |
| molecular characterization and phylogenetic analysis of bjussump-i: a rgd-p-iii class hemorrhagic metalloprotease from bothrops jararacussu snake venom. | snake venom metalloproteases (svmps) embody zinc-dependent multidomain enzymes responsible for a relevant pathophysiology in envenomation, including local and systemic hemorrhage. the molecular features responsible for hemorrhagic potency of svmps have been associated with their multidomains structures which can target these proteins them to several receptors of different tissues and cellular types. bjussump-i, a svmp isolated from the bothrops jararacussu venom, has been characterized as a p-ii ... | 2007 | 17081786 |
| local and systemic pathophysiological alterations induced by a serine proteinase from the venom of the snake bothrops jararacussu. | the local and systemic pathophysiological alterations induced by bjussusp-i, a thrombin-like serine proteinase from the venom of the snake bothrops jararacussu, were assessed in mice. bjussusp-i induced a mild edema but no local myonecrosis or hemorrhage. it did not induce any microvascular alteration in the cremaster muscle. intramuscular injection of bjussusp-i promoted an increase in the expression of prommp-9, but it did not induce the activation of prommp-2 or prommp-9 synthesized in muscle ... | 2007 | 17292935 |
| mapping of the structural determinants of artificial and biological membrane damaging activities of a lys49 phospholipase a2 by scanning alanine mutagenesis. | scanning alanine mutagenesis has been used to study the structural determinants of several activities of bothropstoxin-i (bthtx-i), a lysine 49 phospholipases a(2) from the venom of bothrops jararacussu. a total of 31 mutants were generated in the interfacial recognition site and c-terminal loop regions of the protein. the effects of mutagenesis on the in vivo myotoxic activity, the cytolytic activity against cultured c2c12 myoblasts, the bactericidal activity, and the ca(2+)-independent membran ... | 2007 | 17346668 |
| the co-purification of a lectin (bjcul) with phospholipases a2 from bothrops jararacussu snake venom by immunoaffinity chromatography with antibodies to crotoxin. | antigens of bothrops jararacussu snake venom cross-reacting with specific antibodies against crotoxin, an asp49 pla(2)-containing heterodimeric complex from crotalus durissus terrificus snake venom, were purified by two steps of immunoaffinity chromatography. the resulting fraction (bj-f) was shown to be non-toxic (to mice and rabbits) and immunogenic to rabbits. antibodies raised against bj-f were able to protect mice against the lethal effect of both b. jararacussu and crotalus durissus terrif ... | 2007 | 17391721 |
| bj-48, a novel thrombin-like enzyme from the bothrops jararacussu venom with high selectivity for arg over lys in p1: role of n-glycosylation in thermostability and active site accessibility. | bj-48, a serine protease from the venom of bothrops jararacussu, was purified to homogeneity using affinity chromatography on p-aminobenzamidine-agarose followed by hplc gel filtration. bj-48 presented 52kda by sds-page analysis and 48,036da by electron spray mass spectrometry. the enzyme was shown to be highly glycosylated with 42% of n-linked carbohydrates composed of fuc(1):galn(4):glcn(5):gal(1):man(2) and a high content of sialic acid residues (8-12%). bj-48 had optimal esterase activity at ... | 2007 | 17433397 |
| evaluation of three brazilian antivenom ability to antagonize myonecrosis and hemorrhage induced by bothrops snake venoms in a mouse model. | despite preventing death after snakebites, there is little evidence that polyvalent antivenoms (pavs) protect against myotoxicity and local damages. we evaluated antibothropic brazilian pavs from three manufacturers against the myotoxicity and hemorrhagic activity of bothrops jararacussu and b. jararaca venoms, respectively, by using two protocols: preincubation of pavs with venom, and i.v. pretreatment with pavs, prior to the venom inoculation. in this investigation, we used doses of pavs rangi ... | 2007 | 17466354 |
| bjussusp-i: a new thrombin-like enzyme isolated from bothrops jararacussu snake venom. | a thrombin-like enzyme named bjussusp-i, isolated from b. jararacussu snake venom, is an acidic single chain glycoprotein with approximately 6% sugar, mr=61,000 under reducing conditions and pi approximately 3.8, representing 1.09% of the chromatographic a(280) recovery. bjussusp-i is a glycosylated serine protease containing both n-linked carbohydrates and sialic acid in its structure. bjussusp-i showed a high clotting activity upon human plasma, which was inhibited by pmsf, leupeptin, heparin ... | 2008 | 17466550 |
| neutralization of snake venom phospholipase a2 toxins by aqueous extract of casearia sylvestris (flacourtiaceae) in mouse neuromuscular preparation. | aqueous extract of casearia sylvestris (flacourtiaceae) has been shown to inhibit enzymatic and biological properties of some bothrops and crotalus venoms and their purified phospholipase a(2) (pla(2)) toxins. in this work we evaluated the influence of c. sylvestris aqueous extract upon neuromuscular blocking and muscle damaging activities of some pla(2)s (crotoxin from c. durissus terrificus, bothropstoxin-i from b. jararacussu, piratoxin-i from b. pirajai and myotoxin-ii from b. moojeni) in mo ... | 2007 | 17540522 |
| koninginins, phospholipase a2 inhibitors from endophytic fungus trichoderma koningii. | many isolated compounds from endophytic fungus have been useful to human beings, mainly those with medicinal applications and particularly those that can be used in inflammatory processes. trichoderma fungi produce substances known as koninginins that have great structural similarity to compounds like flavonoids and vitamin e, which are able to inhibit the phospholipase a(2) (pla(2)). in this work, koninginins a, e and f (kona, kone and konf, respectivamente) isolated from trichoderma koningii h ... | 2008 | 17983638 |
| molecular and functional characterization of a new non-hemorrhagic metalloprotease from bothrops jararacussu snake venom with antiplatelet activity. | bjussump-ii is an acidic low molecular weight metalloprotease (mr approximately 24,000 and pi approximately 6.5), isolated from bothrops jararacussu snake venom. the chromatographic profile in rp-hplc and its n-terminal sequence confirmed its high purity level. its complete cdna was obtained by rt-pcr and the 615bp codified for a mature protein of 205 amino acid residues. the multiple alignment of its deduced amino acid sequence and those of other snake venom metalloproteases showed a high struc ... | 2007 | 18006118 |
| ability of suramin to antagonize the cardiotoxic and some enzymatic activities of bothrops jararacussu venom. | we have investigated the cardiotoxic effect of bothrops jararacussu crude venom and the ability of suramin to antagonize this effect in the heart of rats, as well as the proteolytic and phospholipase a(2) (pla(2)) venom activities. continuous perfusion in an isolated heart of a rat on a langendorff preparation with a ringer's solution with b. jararacussu crude venom (2.5-10.0 microg/ml) induces stoppage and a decrease in the cardiac tension, which were time- and concentration dependent. the anal ... | 2008 | 18023464 |
| permeabilization of e. coli k12 inner and outer membranes by bothropstoxin-i, a lys49 phospholipase a2 from bothrops jararacussu. | although lacking catalytic activity, the lys49-pla(2)s damage artificial membranes by a ca(2+)-independent mechanism, and demonstrate a potent bactericidal effect. the relationship between the membrane-damaging activity and bactericidal effect of bothropstoxin-i (bthtx-i), a lys49-pla(2) from the venom of bothrops jararacussu, was evaluated for the wild-type protein and a series of site-directed mutants in the active site and c-terminal regions of the protein. the membrane permeabilization effec ... | 2008 | 18160090 |
| an alternative method to access in vitro the hemorrhagic activity of snake venoms. | local and systemic hemorrhages are major problems concerning bites by viper snakes. therefore, accessing venom hemorrhagic activity is an important feature in order to characterize viper venom major toxicities or to assay antivenom efficacy. the methods currently used to access hemorrhagic activity involve animal experiments and according to the general ethical committees, these procedures should be substituted to in vitro assays in order to minimize animal use in research. in this work, we have ... | 2008 | 18262214 |
| antibothropic action of casearia sylvestris sw. (flacourtiaceae) extracts. | casearia sylvestris sw., popularly known in brazil as 'guaçatonga', has been used as antitumor, antiseptic, antiulcer, local anaesthetic and healer in folk medicine. snakebite envenomation by bothrops jararacussu (bjssu) constitutes a relevant public health hazard capable of inducing serious local damage in victims. this study examined the pharmacological action of apolar and polar c. sylvestris leaf extracts in reverting the neuromuscular blockade and myonecrosis, which is induced by bjssu veno ... | 2008 | 18389489 |
| a novel bradykinin potentiating peptide isolated from bothrops jararacussu venom using catallytically inactive oligopeptidase ep24.15. | characterization of the peptide content of venoms has a number of potential benefits for basic research, clinical diagnosis, development of new therapeutic agents, and production of antiserum. here, we use a substrate-capture assay that employs a catalytically inactive mutant of thimet oligopeptidase (ec 3.4.24.15; ep24.15) to identify novel bioactive peptides in bothrops jararacussu venom. of the peptides captured with inactive ep24.15 and identified by mass spectrometry, three were previously ... | 2008 | 18400032 |
| effect of low-level laser therapy in the inflammatory response induced by bothrops jararacussu snake venom. | this article reports the effect of low-level laser therapy (lllt) on the edema formation and leukocyte influx caused by bothrops jararacussu snake venom as an alternative treatment for bothrops snakebites. the inflammatory reaction was induced by injection of 0.6 mg/kg of b. jararacussu venom, in gastrocnemius muscle. cell influx and edema were evaluated at 3 or 24h after venom injection. mice were irradiated at the site of injury by a low-level laser (685 nm) with a dose of 4.2j/cm(2). a therap ... | 2008 | 18439641 |
| the ability of low level laser therapy to prevent muscle tissue damage induced by snake venom. | antivenom therapy has been ineffective in neutralizing the severe local fast developing tissue damage following snakebite envenoming. herein, some effects of in situ helium neon (hene) laser irradiation on rat nerve-muscle preparation injected with bothrops jararacussu venom are described. the tibialis anterior muscle was injected with venom diluted in 0.9% saline solution (60 microg/0.02 ml) or saline solution alone. sixty minutes after venom injection, laser (hene) treatment was administered a ... | 2009 | 18643907 |
| increase of the cytotoxic effect of bothrops jararacussu venom on mouse extensor digitorum longus and soleus by potassium channel blockers and by na(+)/k(+)-atpase inhibition. | we investigated the myotoxicity of bothrops jararacussu crude venom and other cytolytic agents on mouse isolated extensor digitorum longus (edl) and soleus (sol) muscles, which present distinct properties: edl is a fast-twitch, white muscle with predominantly glycolytic fibers, while sol is slow-twitch, red muscle with predominantly oxidative fibers. muscles were exposed to b. jararacussu crude venom (25 microg/ml) and other crotaline venoms (agkistrodon contortrix laticinctus; crotalus viridis ... | 2008 | 18675839 |
| isolation and characterization of ellagic acid derivatives isolated from casearia sylvestris sw aqueous extract with anti-pla(2) activity. | the casearia sylvestris sw (flacourtiaceae) is utilized in folk medicine (brazil and all latin american) to treat several pathologic processes as inflammation, cancer, microbial infection and snake bites. studies showed that c. sylvestris aqueous extract can inhibit many toxic effects caused by snake venoms (or caused by phospholipase a(2) isolated) from different species, mainly of bothrops genus. inhibition of enzymatic and myotoxic activities, decrease of edema formation and increase of the s ... | 2008 | 18718481 |
| interspecific variation in venom composition and toxicity of brazilian snakes from bothrops genus. | the genus bothrops spp. is responsible for 90% of envenomation by snakes in brazil, and the standard treatment for snakebites is the antivenom therapy. the anti-bothropic serum produced by butantan institute is prepared by the hyperimmunization of horses with a pool of venoms from bothrops alternatus, bothrops jararaca, bothrops jararacussu, bothrops moojeni and bothrops neuwiedi. in this study, the biochemical and biological characteristics of the venoms from nineteen snakes of the genus bothro ... | 2008 | 18983867 |
| antigenic, microbicidal and antiparasitic properties of an l-amino acid oxidase isolated from bothrops jararaca snake venom. | venoms from the bee apis mellifera, the caterpillar lonomia achelous, the spiders lycosa sp. and phoneutria nigriventer, the scorpions tityus bahiensis and tityus serrulatus, and the snakes bothrops alternatus, bothrops jararaca, bothrops jararacussu, bothrops moojeni, bothrops neuwiedi, crotalus durissus terrificus, and lachesis muta were assayed (800mug/ml) for activity against staphylococcus aureus. venoms from b. jararaca and b. jararacussu showed the highest s. aureus growth inhibition and ... | 2009 | 19101583 |
| inhibition of snake venoms and phospholipases a(2) by extracts from native and genetically modified eclipta alba: isolation of active coumestans. | we genetically modified eclipta alba using agrobacterium rhizogenes lba 9402, with the aim of producing secondary metabolites with pharmacological properties against phospholipase a(2) and the myotoxic activities of snake venom. extracts from in natura aerial parts and roots, both native and genetically modified (in vitro), were prepared and analysed by high-performance liquid chromatography. in natura materials showed the coumestan wedelolactone at higher concentration in the aerial parts, whil ... | 2009 | 19320636 |
| purification and preliminary crystallographic analysis of a new lys49-pla2 from b. jararacussu. | bjviii is a new myotoxic lys49-pla2 isolated from bothrops jararacussu venom that exhibits atypical effects on human platelet aggregation. to better understand the mode of action of bjviii, crystallographic studies were initiated. two crystal forms were obtained, both containing two molecules in the asymmetric unit (asu). synchrotron radiation diffraction data were collected to 2.0 a resolution and 1.9 a resolution for crystals belonging to the space group p2(1)2(1)2(1) (a = 48.4 a, b = 65.3 a, ... | 2008 | 19325781 |
| treatment with an anti-inflammatory drug is detrimental for muscle regeneration at bothrops jararacussu envenoming: an experimental study. | we evaluated the effects of deflazacort (dfz) on muscle regeneration following bothrops jararacussu envenoming. tibialis anterior muscle from adult mice was injected with 80 microg of venom. animals received dfz during 6days. seven and 60 days after envenoming, dfz lead to a decrease in the total number of muscle fibers and an increase in interstitial fibrosis. we conclude that dfz treatment may aggravate the loss of muscle mass after b. jararacussu envenoming. | 2009 | 19375446 |