| elisa for the detection of venom antigens in experimental and clinical envenoming by loxosceles intermedia spiders. | enzyme linked immunosorbent assays (elisa) were developed to detect antigens from loxosceles intermedia spider venom. hyperimmune horse anti-loxosceles intermedia iggs were prepared by immunoaffinity chromatography and used to set up a sandwich-type elisa. the specificity of the assay was demonstrated by its capacity to correctly discriminate the circulating antigens in mice that were experimentally inoculated with l. intermedia venom from those inoculated with l. gaucho, l. laeta, and phoneutri ... | 1998 | 9643469 |
| irradiation of crotalus durissus terrificus crotoxin with 60co gamma-rays induces its uptake by macrophages through scavenger receptors. | to investigate the action of 2 kgy 60co gamma-rays on crotoxin and its favoured uptake through scavenger receptor (scvr) mouse peritoneal macrophages. | 1998 | 9652814 |
| tourniquet ineffectiveness to reduce the severity of envenoming after crotalus durissus snake bite in belo horizonte, minas gerais, brazil. | clinical and laboratory data from patients who applied a tourniquet (tourniquet group, n = 45) and who did not apply it (non-tourniquet group, n = 52) after being bitten by crotalus durissus were compared. the patients were treated with 100-200 ml of crotalus durissus antivenom. the gender, age, time elapsed between bite and hospital admission, dose of antivenom and the frequency of local paresthesia, myalgia and palpebral ptosis did not differ between the two groups. plasma creatine kinase enzy ... | 1998 | 9655642 |
| mitochondrial swelling and oxygen consumption during respiratory state 4 induced by phospholipase a2 isoforms isolated from the south american rattlesnake (crotalus durissus terrificus) venom. | the non-covalent interaction between two molecular entities namely, phospholipase a2 and crotapotin, results in the main toxin, crotoxin, present in the venom of the south american rattlesnake crotalus durissus terrificus. high performance liquid chromatography has enabled us the isolation of three phospholipase a2 isoforms (f1, f2 and f3), characterized through denaturing and non-denaturing polyacrylamide gel electrophoresis and also through the n-terminal amino acid sequence analysis. the effe ... | 1998 | 9663696 |
| physical and functional association of the src family kinases fyn and lyn with the collagen receptor glycoprotein vi-fc receptor gamma chain complex on human platelets. | we have previously shown that uncharacterized glycoprotein vi (gpvi), which is constitutively associated and coexpressed with fc receptor gamma chain (fcrgamma) in human platelets, is essential for collagen-stimulated tyrosine phosphorylation of fcrgamma, syk, and phospholipase cgamma2 (plcgamma2), leading to platelet activation. here we investigated involvement of the src family in the proximal signals through the gpvi-fcrgamma complex, using the snake venom convulxin from crotalus durissus ter ... | 1998 | 9670039 |
| [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 |
| effects of crotalus durissus cascavella venom in the isolated rat kidney. | crotalus durissus cascavella (c.d.c) is a snake usually found in scrubland of brazilian northeast and its bite constitutes an important public health problem. isolated kidneys from wistar rats, weighing 240 to 280 g, were perfused with krebs henseleit solution containing 6 g% of previously dialysed bovine serum albumin. the effects of c.d.c venom were studied on the perfusion pressure (pp), urinary flow (uf), glomerular filtration rate (gfr), percent of sodium tubular transport (%tna+) and perce ... | 1998 | 9723842 |
| 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 |
| south american rattlesnake bite (crotalus durissus sp) without envenoming: insights on diagnosis and treatment. | a south american rattlesnake bite without clinical manifestations of envenoming (termed 'dry-bite') has not been recognized to occur by the brazilian ministry of health, which recommends the administration of antivenom to all bitten patients. during 36 months of an observational study on south american rattlesnake bites in minas gerais, brazil, 12% of 41 patients with fang marks at the bite-site did not present clinical or laboratory features of envenoming and had no plasma venom detected before ... | 1998 | 9839686 |
| differential biodistribution of native and 2 kgy 60co irradiated crotoxin in tissues of cba/j mice. | crotalus durissus envenomation is treated using antivenins produced in horses. during production, animals have problems, sometimes followed by death, due to the high toxicity of the main toxin, crotoxin. several methods tested to detoxify this toxin often resulted in decreased immunogenicity. gamma irradiation has proved to be a successful method for crotoxin detoxification without loss of immunogenicity. we have studied the biodistribution of 2 kgy 60co irradiated crotoxin (ictx) in mouse tissu ... | 1998 | 9851508 |
| thermal stability studies of hyperimmune horse antivenoms. | ampoules of horse antivenoms raised against bothrops spp and crotalus durissus (final product) produced by fundação ezequiel dias (funed) were fractionated on the molecular filtration chromatography (superose 12) and the expected mw species of f(ab')2 fragments were observed. it has been known that high temperatures promote aggregation and formation of protein precipitates. phenol is used in preparations of antivenoms as preservative; however, as thus is a hydrophobic substance, it can also indu ... | 1999 | 9920478 |
| comparison of the biological activities in venoms from three subspecies of the south american rattlesnake (crotalus durissus terrificus, c. durissus cascavella and c. durissus collilineatus) | the subspecies of the south american rattlesnake, crotalus durissus are classified according to their external morphological features and geographical distribution. we have determined some biological activities of c. durissus cascavella, c. durissus collilineatus and c. durissus terrificus venoms. c. durissus terrificus had a significantly higher clotting activity on bovine plasma and fibrinogen, human fibrinogen and rabbit plasma. c. durissus cascavella presented a statistically higher phosphol ... | 1999 | 10190029 |
| toxicity and immunogenicity of crotalus durissus terrificus venom treated with different doses of gamma rays. | crotalus durissus terrificus venom (cdt venom) was irradiated with four different doses of gamma rays (2, 3, 5 and 10 kgy) from a 60co source and their structural, toxic and immunogenic properties were analysed. venom irradiated with 2 and 3 kgy were, respectively, 2.7 and 13.5 times less toxic than the native one, whereas the 5 or 10 kgy irradiated venom were at least 100 times less toxic than nonirradiated venom. irradiated venom with all doses were immunogenic and the antibodies elicited by t ... | 1999 | 10400297 |
| neutralizing capacity of antisera raised in horses and rabbits against crotalus durissus terrificus (south american rattlesnake) venom and its main toxin, crotoxin. | crotalus durissus terrificus (south american rattlesnake) venom possesses myotoxic and neurotoxic activities, both of which are also expressed by crotoxin, the principal toxin of this venom. we have investigated the ability of commercial equine antivenom and antivenoms raised in rabbits against c. d. terrificus venom and crotoxin to neutralize the physiological and morphological changes induced by this venom and crotoxin in electrically-stimulated phrenic nerve-diaphragm (pnd) and extensor digit ... | 1999 | 10414861 |
| 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 |
| megaselia scalaris (diptera: phoridae) causing myiasis in crotalus durissus terrificus (serpentes: viperidae) in brazil. | we describe a case of myiasis in crotalus durissus terrificus (laurenti) caused by megaselia scalaris (loew). the snake was found in anhembi, sao paulo, brazil, with a lesion measuring 25 mm in diameter where the larvae of m. scalaris had penetrated the ribs. the opportunistic behavior of the larvae of m. scalaris is discussed. | 1999 | 10534959 |
| gabaergic-benzodiazepine system is involved in the crotoxin-induced anxiogenic effect. | the behavioral effects of crotoxin (ctx), the major component of crotalus durissus terrificus venom, were studied in rats submitted to the open field, holeboard, and social interaction tests. ctx (100, 250, and 500 microg/kg, i.p.) was administered 2 h before the tests. in the open field, ctx reduced ambulation (250 microg/kg) and rearing (250 and 500 microg/kg) and increased grooming (100 and 250 microg/kg) and freezing (250 microg/kg). in the holeboard and social interaction, all the ctx doses ... | 2000 | 10638629 |
| 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 |
| quantification of crotamine, a small basic myotoxin, in south american rattlesnake (crotalus durissus terrificus) venom by enzyme-linked immunosorbent assay with parallel-lines analysis. | intraspecific variation in crotalus durissus terrificus venom composition was studied in relation to crotamine activity. crotamine induces paralysis in extension of hind legs of mice and myonecrosis in skeletal muscle cells. to determine whether the venom of crotamine-negative rattlesnake contains a quantity of myotoxin incapable of inducing paralysis, we have developed a very sensitivity immunological assay method, an enzyme-linked immunoabsorbent assay (elisa), capable of detecting 0.6 ng of p ... | 2000 | 10669031 |
| 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 |
| biochemical characterization of two crotamine isoforms isolated by a single step rp-hplc from crotalus durissus terrificus (south american rattlesnake) venom and their action on insulin secretion by pancreatic islets. | crotamine, a neurotoxin present in the venom of the south american rattlesnake crotalus durrisus terrificus exists as several polymorphic variants, as demonstrated by recombinant dna technology (smith and schmidt, toxicon 28 (1990) 575-585). we have isolated native crotamine by chromatography on sephadex g75, and have purified two crotamine isoforms (f2 and f3) by a single step of rp-hplc. native crotamine and rp-hplc fractions f2 and f3 produced skeletal muscle spasms and spastic paralysis in m ... | 2000 | 10699490 |
| influence of temperature upon effects of crotoxin and gamma-irradiated crotoxin at rat neuromuscular transmission. | the influence of temperature upon the effects of crotoxin (ctx), from crotalus durissus terrificus venom, and gamma-irradiated (60co, 2000 gy) crotoxin (ictx) was studied in rat neuromuscular transmission 'in vitro'. indirect twitches were evoked in the phrenic-diaphragm preparation by supramaximal strength pulses with a duration of 0.5 ms and frequency of 0.5 hz. the phospholipase a(2) (pla(2)) enzymatic activity of ctx and ictx was assayed against phosphadityl choline in triton x-100. at 27 de ... | 2000 | 10713471 |
| delta-opioid receptors and nitric oxide mediate the analgesic effect of crotalus durissus terrificus snake venom. | the antinociceptive effect of crotalus durissus terrificus venom was investigated in a model of inflammatory hyperalgesia induced by carrageenin. the rat paw pressure test was applied before and 3 h after the intraplantar (i.pl.) injection of carrageenin. the venom administered per os before and 1 or 2 h after carrageenin blocked hyperalgesia. when carrageenin was injected in both hind paws and naloxone into one hind paw, antinociception was abolished only in the paw injected with naloxone. d-ph ... | 2000 | 10720635 |
| neutralizing human anti crotoxin scfv isolated from a nonimmunized phage library. | combinatorial phage display technology offers a new possibility for making human antibodies which could be used in immune therapy. we explored the use of this technology to make human scfvs specific for crotoxin, the main toxic component of the venom of the south-american rattlesnake crotalus durissus terrificus. crotoxin, a phospholipase a2 neurotoxin constituted by the association of two subunits, exerts its lethal action by blocking neuromuscular transmission. this is the first report of huma ... | 2000 | 10736105 |
| effect of heating on the toxic, immunogenic and immunosuppressive activities of crotalus durissus terrificus venom. | the venom of south american rattlesnake crotalus durissus terrificus is very toxic but poorly immunogenic and it has an immunosuppressive ability. the heating of venom at 56, 70 or 100 degrees c for 30 min caused a diminution in the lethal, phospholipase a(2) and myotoxic activities. sds-page analysis of the heated venom showed that the proteins of higher molecular weights were the most affected by heating whereas proteins with lower molecular weights (20,000-14, 000) were the most resistant to ... | 2000 | 10758279 |
| convulxin binding to platelet receptor gpvi: competition with collagen related peptides. | convulxin (cvx), a potent platelet aggregating protein from the venom of the snake crotalus durissus terrificus, is known to bind to the platelet collagen receptor, glycoprotein vi (gpvi). cvx binding to human platelets was investigated by flow cytometry, using fluorescein labeled convulxin (fitc-cvx). scatchard analysis indicated high and low affinity binding sites with kd values of 0.6 and 4 nm and bmax values of 1200 and 2000 binding sites per platelet. fitc-cvx binding was inhibited by colla ... | 2000 | 10873594 |
| inhibition of the lethal and myotoxic activities of crotalus durissus terrificus venom by tabernaemontana catharinensis: identification of one of the active components. | in brazilian folk medicine, victims of bites by poisonous animals are usually treated with plant extracts derived from the diverse national flora. the chemical and pharmacological properties of most extracts were yet not investigated. in the rural community of assis-sp, the root bark of tabernaemontana catharinensis ("leiteiro", "cow milk") is applied to the site of the snake bite and believed to neutralize the effect of the venom. we report here the ability of the lyophilized aqueous extract (a ... | 2000 | 10909261 |
| south american rattlesnake bite and soft-tissue infection: report of a case. | the case of a man bitten by a south american rattlesnake (crotalus durissus) and who developed an abscess at the site of the bite is reported. abcesses are a rare complication of this type of envenoming, possibly due to the lack of a strong cytotoxic action of crotalus durissus venom. | 2000 | 10936955 |
| crotoxin, the major toxin from the rattlesnake crotalus durissus terrificus, inhibits 3h-choline uptake in guinea pig ileum. | we examined the effect of crotoxin, the neurotoxic complex from the venom of the south american rattlesnake crotalus durissus terrificus, on the uptake of 3h-choline in minces of smooth muscle myenteric plexus from guinea pig ileum. in the concentration range used (0. 03-1 microm) and up to 10 min of treatment, crotoxin decreased 3h-choline uptake by 50-75% compared to control. this inhibition was time dependent and did not seem to be associated with the disruption of the neuronal membrane, beca ... | 2000 | 10973144 |
| one-month safety study of intraperitoneal vrctc-310-onco (crotoxin + cardiotoxin) in rats. | to evaluate the toxicity of vrctc-310-onco (crotalus durissus terrificus crotoxin + cardiotoxin from naja naja atra), 10 sprague-dawley rats were implanted with intraperitoneal slow-release devices and subjected to treatment with 0.5 microgram/g body weight/d for 14 days. biochemical evidence at days 7 and 14 showed blood, muscular, renal and metabolic disturbance, mostly reversed by day 28. no significant changes were found in necropsy. the limited toxicity of i.p. vrctc-310-onco in rats deserv ... | 2000 | 11050707 |
| intraspecific variation in the venoms of the south american rattlesnake (crotalus durissus terrificus). | the venom of eight individual crotalus durissus terrificus snakes from the state of minas gerais, brazil, in addition to pooled venom from butantan institute, were compared. snakes were captured in distinct locations, some of them 600 km apart: conselheiro lafaiete, entre rios de minas, itauna, itapecerica, lavras, patos de minas, paracatu, and santo antonio do amparo. the crude venoms were tested for proteolytic, phospholipase a2, platelet aggregating, and hemagglutinating activities. the venom ... | 2000 | 11081410 |
| gyroxin fails to modify in vitro release of labelled dopamine and acetylcholine from rat and mouse striatal tissue. | gyroxin fails to modify in vitro release of labelled dopamine and acetylcholine from rat and mouse striatal tissue. gyroxin is a thrombin-like peptide with amidasic, esterasic and fibrinogenolitic activities, found in the venom of snakes like lachesis muta muta and crotalus durissus terrificus. intravenous injections of small doses of gyroxin induce a typical barrel rotation behaviour that has been thought to be a neurotoxic effect. the aim of this study was to determine whether gyroxin-induced ... | 2001 | 11137545 |
| karl heinrich slotta (1895-1987) biochemist: snakes, pregnancy and coffee. | in 1923 karl h. slotta obtained his phd in chemistry from the university of breslau, germany, where he continued to work. at the instigation of the gynaecologist ludwig fraenkel, slotta made the first isolation of progesterone in 1933. in 1934 he proposed the correct structural formula. slotta was appointed professor of chemistry in 1935, but with the oppression of the nazi regime mounting, he soon left germany with his family to take a post at the instituto butantan, brazil. initially he worked ... | 2001 | 11447968 |
| effects of chemical modifications of crotoxin b, the phospholipase a(2) subunit of crotoxin from crotalus durissus terrificus snake venom, on its enzymatic and pharmacological activities. | crotoxin b, the basic asp49-pla(2) subunit from crotoxin, the main component of crotalus durissus terrificus venom, displays myotoxic, edema-inducing, bactericidal (upon escherichia coli), liposomal-disrupting and anticoagulant activities. chemical modifications of his (with 4-bromophenacyl bromide, bpb), tyr (with 2-nitrobenzenesulphonyl fluoride, nbsf), trp (with o-nitrophenylsulphenyl chloride, npsc) and lys (with acetic anhydride) residues of this protein, in addition to cleavage with cyanog ... | 2001 | 11461830 |
| 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 |
| role of crotoxin, a phospholipase a2 isolated from crotalus durissus terrificus snake venom, on inflammatory and immune reactions. | crotoxin (ctx) is a potent neurotoxin from crotalus durissus terrificus snake venom (cdtv) composed of two subunits: one without catalytic activity (crotapotin), and a basic phospolipase a2. recent data have demonstrated that cdtv or ctx inhibit some immune and inflammatory reactions. | 2001 | 11545249 |
| 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 |
| coagulopathy following lethal and non-lethal envenoming of humans by the south american rattlesnake (crotalus durissus) in brazil. | the south american tropical rattlesnake (crotalus durissus subspp) is responsible for approximately 10% of bites from venomous snakes in brazil. we studied 24 victims of bites by this species over 3 years, in south-eastern brazil, particularly investigating haemostatic alterations. thirteen patients were defined as moderately envenomed and 11 as severe. there were two deaths, which were not attributed to venom-induced haemostatic disturbances. however, envenoming by c. durissus is frequently ass ... | 2001 | 11588214 |
| crotalus durissus terrificus snake venom regulates macrophage metabolism and function. | in the present study, we examined the effect of crotalus durissus terrificus venom on rat macrophage metabolism and function. two hours after subcutaneous injection of the venom, peritoneal resident (unstimulated), elicited (thioglycollate-stimulated), and activated mycobacterium bovis strain bacille calmette guérin (bcg) macrophages were collected, and their functional and metabolic parameters were analyzed. the venom inhibited spreading and phagocytosis of macrophages. on the other hand, this ... | 2001 | 11590191 |
| actions of crotalus durissus terrificus venom and crotoxin on the isolated rat kidney. | many studies have reported the occurrence of lethal acute renal failure after snakebites. the aim of the present investigation was to determine alterations in renal function produced by crotalus durissus terrificus venom and crotoxin as well as the histological alterations induced by these venoms. isolated kidneys from wistar rats weighing 240 to 280 g were perfused with krebs-henseleit solution containing 6 g% of previously dialyzed bovine serum albumin. the effects of crotalus durissus terrifi ... | 2001 | 11593312 |
| analysis of fatty acids released by crotoxin in rat brain synaptosomes. | crotoxin, the main toxin of crotalus durissus terrificus venom, exerts its lethal effect by blocking neurotransmission at the neuromuscular junction level through a triphasic mechanism. this effect seems to depend on its phospholipasic activity, suggesting that the mechanism of neurotransmission blockage may be related to fatty acids release in specific sites of the nervous terminal. in this work, we purified the fatty acids released by crotoxin's activity and this outline was compared with othe ... | 2002 | 11602277 |
| isolation and characterization of a convulxin-like protein from crotalus durissus collilineatus venom. | a convulxin (cvx)-like protein was isolated from crotalus durissus collilineatus venom by a combination of molecular exclusion and reversed-phase hplc chromatographies. the molecular mass of the cvx-like protein in the absence and presence of dtt was 78 kda and 12-13 kda, respectively. the cvx-like protein consisted of two nonidentical polypeptide chains (alpha and beta). the n-terminal amino-acid sequences of the alpha and beta subunits were glhcpsdwyaydghcykifneemnwed and gfccpshwssysrycykffsq ... | 2001 | 11838547 |
| antifungal activity of crotalus durissus cumanensis venom. | the susceptibility to crotalus venom of 14 yeast and 10 mould fungal isolates was assessed. this venom was tested in a standardized well diffusion test, using 400 microg/20 microl well. the percentage of susceptibility to yeast isolates was 78.6% (> 8 mm); that for filamentous isolates was 50% (> 8 mm). | 2002 | 11856432 |
| comparison of the biodistribution of free or liposome-entrapped crotalus durissus terrificus (south american rattlesnake) venom in mice. | the local absorption rate, clearance and tissue distribution of crotalus durissus terrificus venom, (cdt) were examined using a two-antibody sandwich elisa assay. we compared the biodistribution of both free or encapsulated cdt in mice. following subcutaneous injection of 10 microg/mouse of free cdt (0.8 ld50), venom was detected in serum after 15 min, showed its highest level at 30 min (45+/-5 ng/ml) and was cleared from the circulation after 6 h. after 2 h of inoculation, venom was detected in ... | 2002 | 11912054 |
| isolation and preliminary enzymatic characterization of a novel pla2 from crotalus durissus collilineatus venom. | a crotoxin homolog was purified from the crotalus durissus collilineatus venom using molecular exclusion and reverse-phase hplc. this crotoxin contained one pla2 (cdcolli iii f6) and four crotapotin isoforms, whereas crotoxin from crotalus durissus terrificus venom had three pla2 iso forms and two crotapotin isoforms. sds-page showed that the c. d. collilineatus pla2 and crotapotin had relative molecular mass of 15 and 9 kda, respectively. neither the pla2 (cdcolli iii f6) nor the crotapotins (c ... | 2002 | 12018613 |
| structural and functional characterization of basic pla2 isolated from crotalus durissus terrificus venom. | the venom of crotalus durissus terrificus was fractionated by reverse-phase hplc to obtain crotapotins (f5 and f7) and pla2 (f15, f16, and f17) of high purity. the phospholipases a2 (pla2s) and crotapotins showed antimicrobial activity against xanthomonas axonopodis pv. passiflorae, although the unseparated crotoxin did not. the f17 of the pla2 also revealed significant anticoagulant activity, althrough for this to occur the presence of glu 53 and trp 61 is important. the f17 of the pla2 showed ... | 2002 | 12018617 |
| snakebites by crotalus durissus ssp in children in campinas, são paulo, brazil. | from january, 1984 to march, 1999, 31 children under 15 y old (ages 1-14 y, median 8 y) were admitted after being bitten by rattlesnakes (crotalus durissus ssp). one patient was classified as "dry-bite", 3 as mild envenoming, 9 as moderate envenoming and 18 as severe envenoming. most patients had neuromuscular manifestations, such as palpebral ptosis (27/31), myalgia (23/31) and weakness (20/31). laboratory tests suggesting rhabdomyolysis included an increase in total blood creatine kinase (ck, ... | 2002 | 12163905 |
| determination of crotalus durissus cascavella venom components that induce renal toxicity in isolated rat kidneys. | envenomation by crotalus durissus terrificus leads to coagulation disorders, myotoxicity, neurotoxicity and acute renal failure (arf). the most serious systemic change and primary cause of death is arf. in this work, we used rp-hplc to isolate crotoxin, convulxin and gyroxin from venom of the related subspecies crotalus durissus cascavella and investigated the effects of these toxins on renal function in the isolated rat kidneys perfused with krebs-henseleit solution containing 6% of bovine seru ... | 2002 | 12165320 |
| geographic and ontogenic variability in the venom of the neotropical rattlesnake crotalus durissus: pathophysiological and therapeutic implications. | a comparative study was performed on the venoms of adult specimens of the neotropical rattlesnake, crotalus durissus, from guatemala, costa rica, venezuela and brazil, together with the venom of newborn specimens of c. d. durissus from costa rica. venoms from brazil (c. d. terrificus) and from newborn specimens of c. d. durissus presented an electrophoretic pattern characterized by the predominance of bands with molecular mass of 36 and 15 kda, whereas those of adult specimens of c. d. durissus ... | 2002 | 12298262 |
| occurrence of cryptosporidium (apicomplexa, cryptosporidiidae) in crotalus durissus terrificus (serpentes, viperidae) in brazil. | the objective of the present study was to investigate the prevalence of cryptosporidium (apicomplexa, cryptosporidiidae) in the snake crotalus durissus terrificus (serpentes, viperidae). fifty animals were evaluated for the presence of oocysts of cryptosporidium sp. at the time of arrival and 30 and 60 days later. intestinal washings with saline solution (1% body weight), fecal samples, and organ scrapings were collected during the study. oocysts were concentrated by an ether-phosphate-buffered ... | 2002 | 12386695 |
| 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 |
| solution structure of crotamine, a na+ channel affecting toxin from crotalus durissus terrificus venom. | crotamine is a component of the venom of the snake crotalus durissus terrificus and it belongs to the myotoxin protein family. it is a 42 amino acid toxin cross-linked by three disulfide bridges and characterized by a mild toxicity (ld50 = 820 micro g per 25 g body weight, i.p. injection) when compared to other members of the same family. nonetheless, it possesses a wide spectrum of biological functions. in fact, besides being able to specifically modify voltage-sensitive na+ channel, it has bee ... | 2003 | 12709056 |
| renal effects of supernatant from macrophages activated by crotalus durissus cascavella venom: the role of phospholipase a2 and cyclooxygenase. | in brazil, the genus crotalus is responsible for approximately 1500 cases of snakebite annually. the most common complication in the lethal cases is acute renal failure, although the mechanisms of the damaging effects are not totally understood. in this work, we have examined the renal effects caused by a supernatant of macrophages stimulated by crotalus durissus cascavella venom as well the potential role of phospholipase a2 and cyclo-oxygenase. rat peritoneal macrophages were collected and pla ... | 2003 | 12710592 |
| inflammatory oedema induced by phospholipases a2 isolated from crotalus durissus sp. in the rat dorsal skin: a role for mast cells and sensory c-fibers. | the ability of the phospholipases a(2) (pla(2)s) from crotalus durissus cascavella, crotalus durissus collilineatus and crotalus durissus terrificus venoms and crotapotin to increase the vascular permeability in the rat skin as well as the contribution of both mast cells and sensory c-fibers have been investigated in this study. vascular permeability was measured as the plasma extravascular accumulation at skin sites of intravenously injected 125i-human serum albumin. intradermal injection of cr ... | 2003 | 12782082 |
| contribution of crotoxin for the inhibitory effect of crotalus durissus terrificus snake venom on macrophage function. | previous work of our group demonstrated that crotalus durissus terrificus venom has a dual effect on macrophage function: it inhibits spreading and phagocytosis and stimulates hydrogen peroxide and nitric oxide production, antimicrobial activity and glucose and glutamine metabolism of these cells. crotalid venom also induces analgesia and this effect is mediated by opioid receptors. the involvement of opioidergic mechanism and the determination of the active component responsible for the inhibit ... | 2003 | 12782091 |
| activation of peripheral atp-sensitive k+ channels mediates the antinociceptive effect of crotalus durissus terrificus snake venom. | the role of peripheral potassium channels on the antinociceptive effect of crotalus durissus terrificus venom, a mixed delta- and kappa-opioid receptor agonist, was investigated in hyperalgesia induced by carrageenin or prostaglandin e(2). rat paw pressure test was applied before and 3 h after the intraplantar (i.pl.) injection of the nociceptive stimuli. oral administration of venom 2 h after carrageenin or prostaglandin e(2) induces antinociception. local pretreatment with 4-aminopyridine and ... | 2003 | 12782185 |
| structural, enzymatic and biological properties of new pla(2) isoform from crotalus durissus terrificus venom. | we isolated a new pla(2) from the crotalus durissus terrificus venom that designated f15, which showed allosteric behavior with a v(max) of 8.5nmol/min/mg and a k(m) of 38.5 mm. the incubated heparin salt of this isolated f15 act a positive allosteric effector by increasing the v(max) to 10.2 nmol/min/mg, with decreasing the v(max) value to 20.5 mm. the crotapotin, on the other hand acts as a negative allosteric effector by increasing the v(max) values to 58.4 mm. f15 also showed high calcium de ... | 2003 | 12875878 |
| convulxin binds to native, human glycoprotein ib alpha. | convulxin (cvx), a c-type snake protein from crotalus durissus terrificus venom, is the quintessential agonist for studies of the collagen receptor, glycoprotein vi (gpvi) and its role in platelet adhesion to collagens. in this study, cvx, purified from venom, behaves as expected, i.e. it binds to platelet gpvi and recombinant human gpvi, induces platelet aggregation and platelet prothrombinase activity, and binds uniquely to gpvi in ligand blots of sds-denatured proteins. nonetheless, we find t ... | 2003 | 12881531 |
| structural and biological characterization of a crotapotin isoform isolated from crotalus durissus cascavella venom. | envenoming by crotalus durissus subspecies leads to coagulation disorders, myotoxicity, neurotoxicity and acute renal failure. the most serious systemic alteration and primary cause of death after snakebite is acute renal failure. in this work, we isolated crotapotin, an acid component (crtp) of crotoxin from crotalus durissus cascavella venom and we investigated its bactericidal and pro-inflammatory activities as well as its renal effects in rat isolated perfused kidneys. crtp was bactericidal ... | 2003 | 12893061 |
| inhibitory potential of crotalus durissus terrificus venom on measles virus growth. | this paper presents the antiviral activity found in a snake with crotalus durissus terrificus venom (cdt), studied by use of microplate inhibition assay, using measles virus (mv). cdt at concentrations below 100 microg/ml showed no cytotoxicity for vero cells. this study shows the optimal conditions for cell treatment and infection. two factors that affect virus binding and infection efficiency were studied: the use of an adsorption step, where infection volume was varied; and the concentration ... | 2003 | 12906885 |
| a new serovar and a new serological variant belonging to salmonella enterica subspecies diarizonae. | description of a new serovar (s. iiib 16:k:e,n,x,z15) and a new serological variant (s. iiib 42:z10:e,n,x,z15:z60 ) belonging to the genus salmonella isolated from stool specimens of brazilian snakes (crotalus durissus). | 2003 | 12937762 |
| 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 |
| hematological, hemostatic and clinical chemistry disturbances induced by crotalus durissus terrificus snake venom in dogs. | the aim of this study was to investigate the hematological, hemostatic and biochemical disturbances induced by the injection of crotalus durissus terrificus venom in dogs under controlled conditions. for this purpose three groups of animals were used: an experimental group (e), which was injected i.m. with c. durissus terrificus venom (1 mg/kg); and two control groups--antivenom (av) and control (c)--which were injected i.m. with 150 mm nacl. groups e and av were treated i.v. with crotalus antiv ... | 2003 | 14580009 |
| description of the gamonts of a small species of hepatozoon sp. (apicomplexa, hepatozoidae) found in crotalus durissus terrificus (serpentes, viperidae). | a small species of the genus hepatozoon found in a specimen of crotalus durissus terrificus from the botucatu region, são paulo state, brazil is described. the morphologic alterations induced in the snake's erythrocytes by the presence of this parasite are described. morphology and morphometric analyses were performed using the qwin lite 2.5 computerized image analysis system (leica). the hepatozoon possessed a small and short body (8.1+/-0.5 microm long and 3.8+/-0.4 microm wide), with round ex ... | 2004 | 14628216 |
| anticrotalic and antitumoral activities of gel filtration fractions of aqueous extract from tabernaemontana catharinensis (apocynaceae). | the high mortality caused by crotalus durissus terrificus snake venom is mainly due to crotoxin, which acts on the neuromuscular junction inhibiting the mechanism mediating acetylcholine release, thus leading to motor and respiratory paralysis and subsequently to animal death. we recently demonstrated that the aqueous extract (ae) of tabernaemontana catharinensis can inhibit the lethal activity of c. d. terrificus venom. eight fractions, pi to pviii, were obtained by gel filtration of the extrac ... | 2004 | 14984700 |
| neurotoxic and myotoxic actions of crotoxin-like and crotalus durissus cascavella whole venom in the chick biventer cervicis preparation. | crotoxin from crotalus durissus cascavella venom was purified by a combination of molecular exclusion chromatography (superdex 75 column) and hplc molecular exclusion (protein pack 300sw column). neurotoxic and myotoxic effects from c. durissus cascavella whole venom and its main fraction, the crotoxin-like, were studied in the chick biventer cervicis (cbc) nerve-muscle preparation. both venom and its crotoxin showed significant (p < 0.05) blockade of neuromuscular transmission at concentrations ... | 2004 | 15033323 |
| cyclosporin a attenuates skeletal muscle damage induced by crotoxin in rats. | this work was undertaken to determine the role of the calcineurin pathway on the necrosis of skeletal muscle induced by crotoxin, the major component of the venom of crotalus durissus terrificus. rats were treated with cyclosporin a (csa), a calcineurin inhibitor, for 5 days and, in the 6th day, received an intramuscular injection of crotoxin into the tibialis anterior muscle. rats were also treated with diclofenac, a non-steroidal anti-inflammatory drug, for 5 days and, on the 6th day, injected ... | 2004 | 15037027 |
| role of nitric oxide in myotoxic activity induced by crotoxin in vivo. | this study was aimed to determine the role of nitric oxide on the skeletal myotoxic activity induced by crotoxin, the major component of the venom of crotalus durissus terrificus. rats were treated with n(g)-nitro-l-arginine methyl ester (l-name), a non-selective inhibitor of nitric oxide synthase or vehicle for 4 days, and on the 5th day received an intramuscular injection of crotoxin into the tibialis anterior muscle. rats were also treated with aminoguanidine bicarbonate salt or 7-nitroindazo ... | 2004 | 15051406 |
| location of the ureteral openings in the cloacas of tinamous, some ratite birds, and crocodilians: a primitive character. | cloacas of 67 avian species, of both sexes, from various habitats and differing dietary habits, were examined macro- and microscopically to investigate possible variation in the location of the ureteral openings. differing from most birds studied, in adult male rhea americana and several tinamous species the ureters were found to open into the coprodeum. in these species the urodeum receives only the vas deferens or oviduct. similarly, in crocodiles caiman crocodilus yacare, but not in lizards t ... | 2004 | 15108162 |
| pharmacological evidence for a presynaptic action of venoms from bothrops insularis (jararaca ilhoa) and bothrops neuwiedi (jararaca pintada). | whereas the presynaptic action of crotalus durissus terrificus venom is well-established, bothrops venoms have historically been considered to have only postsynaptic and muscular effects. however, some studies have also suggested a presynaptic action for these venoms. in this work, we used chick biventer cervicis preparations to compare the presynaptic actions of two bothrops venoms (b. insularis and b. neuwiedi) with that of c. d. terrificus venom. at 10 microg/ml, all venoms produced irreversi ... | 2004 | 15109884 |
| peripheral neuronal nitric oxide synthase activity mediates the antinociceptive effect of crotalus durissus terrificus snake venom, a delta- and kappa-opioid receptor agonist. | previous work has shown that nitric oxide (no) mediates the antinociceptive effect of crotalus durissus terrificus venom on carrageenin-induced hyperalgesia. in the present study the role of constitutive neuronal or of inducible form of nitric oxide synthase on venom effect was determined. the rat paw prostaglandin e(2) (pge(2))-induced mechanical hyperalgesia model was used for nociceptive evaluation. the venom (200 microg/kg) administered per oz immediately before prostaglandin induced antinoc ... | 2004 | 15158366 |
| crotamine is a novel cell-penetrating protein from the venom of rattlesnake crotalus durissus terrificus. | herein we report that crotamine, a small lysine- and cysteine-rich protein from the venom of the south american rattlesnake, can rapidly penetrate into different cell types and mouse blastocysts in vitro. in vivo crotamine strongly labels cells from mouse bone marrow and spleen and from peritoneal liquid, as shown by fluorescent confocal laser-scanning microscopy. nuclear localization of crotamine was observed in both fixed and unfixed cells. in the cytoplasm, crotamine specifically associates w ... | 2004 | 15231729 |
| anti-sera raised in rabbits against crotoxin and phospholipase a2 from crotalus durissus cascavella venom neutralize the neurotoxicity of the venom and crotoxin. | crotoxin, the principal neurotoxin in venom of the south american rattlesnakes crotalus durissus terrificus and crotalus durissus cascavella, contains a basic phospholipase a2 (pla2) and an acidic protein, crotapotin. in this work, we examined the ability of rabbit anti-sera against crotoxin and its pla2 subunit to neutralize the neurotoxicity of venom and crotoxin from c. d. cascavella in mouse phrenic nerve-diaphragm and chick biventer cervicis preparations. immunoblotting showed that the anti ... | 2004 | 15246761 |
| identification of crotasin, a crotamine-related gene of crotalus durissus terrificus. | crotamine is a cationic peptide (4.9 kda, pi 9.5) of south american rattlesnake, crotalus durissus terrificus' venom. its presence varies according to the subspecies or the geographical locality of a given species. at the genomic level, we observed the presence of 1.8 kb gene, crt-p1, in crotamine-positive specimens and its absence in crotamine-negative ones. in this work, we described a crotamine-related 2.5 kb gene, crotasin (cts-p2), isolated from crotamine-negative specimens. reverse transcr ... | 2004 | 15284009 |
| a comparative study of biological activities of crotoxin and cb fraction of venoms from crotalus durissus terrificus, crotalus durissus cascavella and crotalus durissus collilineatus. | in brazil, the crotalus durissus terrificus subspecie is the most studied, particularly concerning its crotoxin. crotoxin is the major toxic component of the south american rattlesnake crotalus durissus venom. it is composed of two different subunits, ca called crotapotin and cb weakly toxic phospholipase a2 with high enzymatic activity. in this paper, we decided to make a study of the main toxic characteristics of crotoxin (ctx) and cb fraction from the other subspecies, crotalus durissus casca ... | 2004 | 15284014 |
| characterization of bothrops jararaca coagulation inhibitor (bji) and presence of similar protein in plasma of other animals. | bji, a protein isolated from bothrops jararaca snake blood, inhibits the coagulant activity of thrombin. this protein presents two bands of 109 and 138 kda by sds-page under reducing conditions. in order to verify the presence of bji-like proteins in plasma of other animals (reptiles and non-reptiles), we raised a specific polyclonal antibody in mice to it, and we verified immunological cross-reaction by western blotting, considering as positive reactions the development of bands with either 109 ... | 2004 | 15302535 |
| thalidomide and pentoxifylline block the renal effects of supernatants of macrophages activated with crotalus durissus cascavella venom. | because thalidomide and pentoxifylline inhibit the synthesis and release of tumor necrosis factor-alpha (tnf-alpha), we determined the effect of these drugs on the renal damage induced by supernatants of macrophages activated with crotalus durissus cascavella venom in order to identify the role of tnf-alpha in the process. rat peritoneal macrophages were collected with rpmi medium and stimulated in vitro with c.d. cascavella venom (10 micro g/ml) in the absence and presence of thalidomide (15 mi ... | 2004 | 15448874 |
| sperm storage in males of the snake crotalus durissus terrificus (crotalinae: viperidae) in southeastern brazil. | seasonal variations in spermatozoa numbers and in sperm motility along the vas deferens in crotalus durissus terrificus from southeastern brazil were analyzed. our data demonstrate storage and motility of the spermatozoa along the vas deferens throughout the year. this is characteristic of a postnuptial reproductive cycle, usually found in snakes living in temperate climates. we describe similarities in reproductive cycle patterns found in the tropical nonhibernator c. durissus terrificus and in ... | 2004 | 15528165 |
| effect of crotapotin on the biological activity of asp49 and lys49 phospholipases a(2) from bothrops snake venoms. | myonecrosis, in addition to edema and other biological manifestations, are conspicuous effects of bothrops snake venoms, some of them caused by phospholipases a(2) (pla(2)s). asp49-pla(2)s are catalytically active, whereas lys49-pla(2)s, although highly toxic, have little or no enzymatic activity upon artificial substrates, due to a substitution of lysine for aspartic acid at position 49. crotapotin (ca), the acidic counterpart of crotoxin pla(2) (cb), is a pla(2)-like protein from crotalus duri ... | 2004 | 15536050 |
| [secreted phospholipases a2 (spla2): friends or foes? are they actors in antibacterial and anti-hiv resistance?]. | in this paper the authors update on the deletereous or beneficial roles of human and animal secretory phospholipases a2 (spla2). although human spla2-iia (inflammatory) was initially thought as a foe because its pathogenic implication in sepsis, multiorganic failure or other related syndromes, recent data indicates its role in in the antiinfectious host resistance. thus, spla2-iia exhibits potent bactericidal activities against gram-negative and gram-positive (in this case, together with other e ... | 2004 | 15574291 |
| characterization of the insulinotropic action of a phospholipase a2 isolated from crotalus durissus collilineatus rattlesnake venom on rat pancreatic islets. | the ability of pla2 and crotapotin, isolated from crotalus durissus collilineatus rattlesnake venom, to stimulate insulin secretion from isolated rat islets was examined. pla2 and crotapotin stimulated insulin secretion at 2.8 mmol/l glucose, whereas at a high glucose concentrations (16.7 mmol/l) only pla2 stimulated secretion. nifedipine (10 micromol/l) did not alter the ability of pla2 to increase insulin secretion stimulated by a depolarizing concentration of k+ (30 mmol/l). pla2 did not affe ... | 2005 | 15626373 |
| mice plasma fibrinogen consumption by thrombin-like enzyme present in rattlesnake venom from the north-east region of argentina. | due to variability of venom components from the same species of snakes that inhabit different regions, particular properties of the venom of crotalus durissus terrificus that inhabits the north-east of argentina were studied. gyroxin, a thrombin-like enzyme, was isolated from this venom by gel filtration and affinity chromatography, it was found to be homogeneous according to sds-page, with a molecular weight of 33 kda. "gyroxin syndrome" in mice was tested and it showed changes in the animal be ... | 2004 | 15637828 |
| [toxicity of venoms from snakes of medical importance in méxico]. | the characterization of the toxic activities of snake venoms is necessary to understand the physiopathology of the envenomation and to test the potency of the antivenoms used to treat this pathology. because of the lack of data on the toxic activities of venoms from mexican snakes of medical importance, we studied the venoms from bothrops asper, athropoides nummifrr, agkistrodon billineatus, crotalus durissus durissus, crotalus basiliscus, crotalus scutulatus, crotalus atrox and micrurus nigroci ... | 2005 | 15754746 |
| structure-function relationship of new crotamine isoform from the crotalus durissus cascavella. | in this work we isolated a novel crotamine like protein from the crotalus durissus cascavella venom by combination of molecular exclusion and analytical reverse phase hplc. its primary structure was:ykrchkkgghcfpkekiclppssdlgkmdcrwkrk-cckkgs gk. this protein showed a molecular mass of 4892.89 da that was determined by matrix assisted laser desorption ionization time-of-flight (maldi-tof) mass spectrometry. the approximately pi value of this protein was determined in 9.9 by two-dimensional electr ... | 2005 | 15756813 |
| 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 |
| inhibitory effect of phospholipase a(2) isolated from crotalus durissus terrificus venom on macrophage function. | recent work demonstrated that crotoxin, the main toxin of crotalus durissus terrificus venom, inhibits macrophage spreading and phagocytic activities. the crotoxin molecule is composed of two subunits, an acidic non-toxic and non-enzymatic polypeptide named crotapotin and a weakly toxic basic phospholipase a(2) (pla(2)). in the present work, the active subunit responsible for the inhibitory effect of crotoxin on macrophage function was investigated. peritoneal macrophages harvested from naive ra ... | 2005 | 15777963 |
| specific identification of lachesis muta muta snake venom using antibodies against the plasminogen activator enzyme, lv-pa. | sandwich-type enzyme linked immunosorbent assays (elisa) were developed to detect lachesis muta muta (bushmaster) snake venom using antibodies against the plasminogen activator enzyme (lv-pa). antibodies to lv-pa were obtained by immunization of one rabbit with the purified enzyme. the igg fraction was purified from rabbit blood in a single step on a column of sepharose-l. m. muta venom and used to coat the microtiter plates. the specificity of the assay was demonstrated by its capacity to corre ... | 2005 | 15804530 |
| biological and structural characterization of a new pla2 from the crotalus durissus collilineatus venom. | in the present article we report on the biological characterization and amino acid sequence of a new basic phospholipases a2 (pla2) isolated from the crotalus durissus collilineatus venom (cdcolli f6), which showed the presence of 122 amino acid residues with a pi value of 8.3, molecular mass of 14 kda and revealed an amino acid sequence identity of 80% with crotalic pla2s such as mojave b, cdt f15, and croatox. this homology, however, dropped to 50% if compared to other sources of pla2s such as ... | 2005 | 16003952 |
| 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 |
| new view on crotamine, a small basic polypeptide myotoxin from south american rattlesnake venom. | crotamine is a toxin from the crotalus durissus terrificus venom, composed of 42 amino acid residues and three disulfide bridges. it belongs to a toxin family previously called small basic polypeptide myotoxins (sbpm) whose members are widely distributed through the crotalus snake venoms. comparison of sbpm amino acid sequences shows high similarities. crotamine induces skeletal muscle spasms, leading to spastic paralysis of the hind limbs of mice, by interacting with sodium channels on muscle c ... | 2005 | 16115660 |
| a biogeographic comment on: wüster et al. (2005) tracing an invasion: landbridges, refugia, and the phylogeography of the neotropical rattlesnake (serpentes: viperidae: crotalus durissus). | | 2005 | 16156828 |
| 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 |
| venous tone and cardiac function in the south american rattlesnake crotalus durissus: mean circulatory filling pressure during adrenergic stimulation in anaesthetised and fully recovered animals. | the effects of adrenergic stimulation on mean circulatory filling pressure (mcfp), central venous pressure (p(cv)) and stroke volume (vs), as well as the effects of altered mcfp through changes of blood volume were investigated in rattlesnakes (crotalus durissus). mcfp is an estimate of the upstream pressure driving blood towards the heart and is determined by blood volume and the activity of the smooth muscle cells in the veins (venous tone). mcfp can be determined as the plateau in p(cv) durin ... | 2005 | 16169952 |
| effects of morin on snake venom phospholipase a2 (pla2). | flavonoids are potent anti-inflammatory compounds isolated from several plant extracts, and have been used experimentally against inflammatory processes. in this work, a pla2 isolated from the crotalus durissus cascavella venom and rat paw oedema were used as a model to study the effect of flavonoids on pla2. we observed that a treatment of pla2 with morin induces several modifications in the aromatic amino acids, with accompanying changes in its amino acid composition. in addition, results from ... | 2005 | 16185736 |
| inhibition of crotoxin binding to synaptosomes by a receptor-like protein from crotalus durissus terrificus (the south american rattlesnake). | crotoxin (ctx) is a potent neurotoxin of the venom of crotalus durissus terrificus (the south american rattlesnake). ctx is a heterodimer composed of cb, a toxic pla(2) subunit, and ca, a non-toxic and non-enzymatic subunit, that potentiates the neurotoxicity of cb in vivo. the deleterious action of ctx upon c. d. terrificus snakes themselves is known to be prevented by a pla(2) inhibitor (cnf) present in their blood serum. cnf acts by replacing ca in ctx, thus forming a new stable complex cnf-c ... | 2005 | 16246298 |
| individual venom variability in crotalus durissus ruruima snakes, a subspecies of crotalus durissus from the amazonian region. | venoms of six specimens of crotalus durissus ruruima snakes from the same geographical site in the brazilian state of roraima, were individually assayed for their main pharmacological properties. quantitative and qualitative differences were found and the presence of crotoxin-like isoforms in these venoms was indicated. our findings corroborate the existence of a considerable intrapopulational variability in c. d. ruruima venoms, and the importance of using a pool of venoms for antivenom product ... | 2005 | 16269162 |
| identification and functional analysis of a novel bradykinin inhibitory peptide in the venoms of new world crotalinae pit vipers. | a novel undecapeptide has been isolated and structurally characterized from the venoms of three species of new world pit vipers from the subfamily, crotalinae. these include the mexican moccasin (agkistrodon bilineatus), the prairie rattlesnake (crotalus viridis viridis), and the south american bushmaster (lachesis muta). the peptide was purified from all three venoms using a combination of gel permeation chromatography and reverse-phase hplc. automated edman degradation sequencing and maldi-tof ... | 2005 | 16277978 |
| biochemical, pharmacological and structural characterization of a new pla2 from crotalus durissus terrificus (south american rattlesnake) venom. | a new pla2 (f16) was purified from crotalus durissus terrificus venom by molecular exclusion chromatography followed by analytical reverse phase hplc. the pla2 (14.86 kda by maldi-tof mass spectrometry) had an amino acid sequence of sllqfnkmikfetrknavpfyafygcycgwggrrrpkdatdrccfvhdccyekvtkcntkwdiyryslksgyitcgkgtwckeqicecdrvaaeclrrslstykngymfypdsrcrgpsetc, and showed highly conserved ca2+-binding and catalytic sites. f16 showed allosteric behavior with 10 mm ca2+ and had temperature and ph optima ... | 2005 | 16283546 |