Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
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| structure and chromosomal localization of the gene for crotamine, a toxin from the south american rattlesnake, crotalus durissus terrificus. | crotamine is a 42 amino acid-long basic polypeptide, one of the major components of the south american rattlesnake, crotalus durissus terrificus, venom. the mrna has about 340 nucleotides and codifies a pre-crotamine, including the signal peptide, the mature crotamine, and a final lysine. in this report, we describe the crotamine gene with 1.8 kb organized into three exons separated by a long phase-1 (900 bp) and a short phase-2 (140 bp) introns. exon 1 includes the 5'-untranslated region and co ... | 2003 | 14757205 |
| the ventilatory response to environmental hypercarbia in the south american rattlesnake, crotalus durissus. | to study the effects of environmental hypercarbia on ventilation in snakes, particularly the anomalous hyperpnea that is seen when co(2) is removed from inspired gas mixtures (post-hypercapnic hyperpnea), gas mixtures of varying concentrations of co(2) were administered to south american rattlesnakes, crotalus durissus, breathing through an intact respiratory system or via a tracheal cannula by-passing the upper airways. exposure to environmental hypercarbia at increasing levels, up to 7% co(2), ... | 2004 | 14767598 |
| 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 |
| cardiovascular actions of rattlesnake bradykinin ([val1,thr6]bradykinin) in the anesthetized south american rattlesnake crotalus durissus terrificus. | incubation of heat-denatured plasma from the rattlesnake crotalus atrox with trypsin generated a bradykinin (bk) that contained two amino acid substitutions (arg1 --> val and ser6 --> thr) compared with mammalian bk. bolus intra-arterial injections of synthetic rattlesnake bk (0.01-10 nmol/kg) into the anesthetized rattlesnake, crotalus durissus terrificus, produced a pronounced and concentration-dependent increase in systemic vascular conductance (gsys). this caused a fall in systemic arterial ... | 2005 | 15498967 |
| immunosuppresive role of principal toxin (crotoxin) of crotalus durissus terrificus venom. | the composition of the crotalic venom and the immunochemistry and/or pathophysiological characterization and main components were well studied. however, few studies have been carried out to investigate the effect of toxins of this venom on the development of the immune response. the objective of this work was to find out if venom or crotoxin of crotalus durissus terrificus was able to modulate the immune response through its ability to change the mediators involved in the immune response by an u ... | 2004 | 15501286 |
| reproductive cycle of the neotropical crotalus durissus terrificus: i. seasonal levels and interplay between steroid hormones and vasotocinase. | crotaline snakes present delayed fertilization and sperm storage because secondary vitellogenesis is not completed by the time of mating. the release of vitellogenesis and synchrony between ovulation and fertilization suggest a steroidal modulation. we investigated changes of sexual steroid levels during reproduction in the neotropical rattlesnake crotalus durissus terrificus, analyzing macroscopical variations of reproductive condition (vitellogenesis, pregnancy, and post-partum) and plasma lev ... | 2004 | 15504392 |
| reproductive cycle of the neotropical crotalus durissus terrificus: ii. establishment and maintenance of the uterine muscular twisting, a strategy for long-term sperm storage. | crotaline snakes store sperm by means of a uterine musculature twisting (umt). we investigated the influence of plasma levels of estradiol and progesterone and vasotocinase cystine aminopeptidase (cap) activity on umt formation and maintenance, and the in vitro uterine reactivity for avt in crotalus durissus terrificus in primary or secondary vitellogenesis with or without umt. frequency of females in secondary vitellogenesis with umt is significantly higher than in primary one. estradiol levels ... | 2004 | 15504393 |
| 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 |
| acute renal failure after crotalus durissus snakebite: a prospective survey on 100 patients. | acute renal failure (arf) is the main cause of death after the south american crotalid snakebite. the aim of this study was to assess the prevalence, risk factors, and characteristics of crotalus durissus venom-induced arf. | 2005 | 15673314 |
| the role of nitric oxide in the regulation of the systemic and pulmonary vasculature of the rattlesnake, crotalus durissus terrificus. | the functional role of nitric oxide (no) was investigated in the systemic and pulmonary circulations of the south american rattlesnake, crotalus durissus terrificus. bolus, intra-arterial injections of the no donor, sodium nitroprusside (snp) caused a significant systemic vasodilatation resulting in a reduction in systemic resistance (rsys). this response was accompanied by a significant decrease in systemic pressure and a rise in systemic blood flow. pulmonary resistance (rpul) remained constan ... | 2005 | 15726384 |
| chromatin supraorganization, dna fragmentation, and cell death in snake erythrocytes. | in nucleate erythrocytes of several vertebrate groups, the frequency and intensity of dna fragmentation associated with programmed cell death vary considerably. although hemoglobin efficiency may be related to erythrocyte life span, and hemoglobin types and erythrocyte life spans are assumed to vary in reptiles, no data on dna fragmentation and chromatin organization as related to cell death exist for snakes. in the present study, chromatin supraorganization, dna fragmentation, and cell death we ... | 2005 | 15746963 |
| [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 |
| tracing an invasion: landbridges, refugia, and the phylogeography of the neotropical rattlesnake (serpentes: viperidae: crotalus durissus). | abstract pleistocene fragmentation of the amazonian rainforest has been hypothesized to be a major cause of neotropical speciation and diversity. however, the role and even the reality of pleistocene forest refugia have attracted much scepticism. in amazonia, previous phylogeographical studies have focused mostly on organisms found in the forests themselves, and generally found speciation events to have predated the pleistocene. however, molecular studies of open-formation taxa found both north ... | 2005 | 15773938 |
| 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 |
| on the unsual hemorrhagic and necrotic activities caused by the rattlesnake (crotalus durissus cumanensis) in a venezuelan patient. | the hemorrhagic, necrotic and edematous effects observed in a 23-year-old patient from lagunetica, los teques, state of miranda, venezuela, that was bitten by a common venezuelan rattlesnake (crotalus durissus cumanensi), were described. the patient was treated with polyvalente serum, antibiotics and autograft. this finding allows to suggest that the poison of some venezuelan common rattlesnakes has a systemic effect on the skeletal muscle and on capillaries that generate edema, hemorragic pheno ... | 2009 | 15849951 |
| crotalidae polyvalent immune fab (ovine) antivenom is effective in the neutralization of south american viperidae venoms in a murine model. | crotalidae polyvalent immune fab (ovine) (crofab; fabav) is used in the treatment of symptomatic crotaline envenomations in north america. unlike antivenin (crotalidae) polyvalent, which is approved for treatment of crotaline envenomation in north and south america, fabav is manufactured using only venoms from crotaline snakes native to the united states. this study was designed to evaluate the efficacy of fabav in the neutralization of venom from 2 south american crotaline snakes: crotalus duri ... | 2005 | 15940091 |
| hypoxic pulmonary vasoconstriction in reptiles: a comparative study of four species with different lung structures and pulmonary blood pressures. | low o2 levels in the lungs of birds and mammals cause constriction of the pulmonary vasculature that elevates resistance to pulmonary blood flow and increases pulmonary blood pressure. this hypoxic pulmonary vasoconstriction (hpv) diverts pulmonary blood flow from poorly ventilated and hypoxic areas of the lung to more well-ventilated parts and is considered important for the local matching of ventilation to blood perfusion. in the present study, the effects of acute hypoxia on pulmonary and sys ... | 2005 | 15961533 |
| 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 |
| biochemical and enzymatic characterization of two basic asp49 phospholipase a2 isoforms from lachesis muta muta (surucucu) venom. | two basic phospholipase a2 (pla2) isoforms were isolated from lachesis muta muta snake venom and partially characterized. the venom was fractionated by molecular exclusion chromatography in ammonium bicarbonate buffer followed by reverse-phase hplc on a c-18 mu-bondapack column and rp-hplc on a c-8 column. from liquid chromatography-electrospray ionization/mass spectrometry, the molecular mass of the two isoforms lmtx-i and lmtx-ii was respectively measured as 14,245.4 and 14,186.2 da. the pi wa ... | 2005 | 16005152 |
| 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 |
| software system for three-dimensional volumetric reconstruction of histological sections: a case study for the snake chondrocranium. | volumetric digital computer-assisted reconstruction of histological sections is an attractive possibility for developmental studies. commercial solutions are very expensive for many educational institutions. therefore, we developed a software system for three-dimensional reconstruction of anatomical virtual models. the input data for the system are the digitized images from the histological samples of the chondrocranium of two crotalines, bothrops jararaca and crotalus durissus terrificus, and o ... | 2005 | 16114067 |
| 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 |
| automated nmr structure determination and disulfide bond identification of the myotoxin crotamine from crotalus durissus terrificus. | crotamine is one of four major components of the venom of the south american rattlesnake crotalus durissus terrificus. similar to its counterparts in the family of the myotoxins, it induces myonecrosis of skeletal muscle cells. this paper describes a new nmr structure determination of crotamine in aqueous solution at ph 5.8 and 20 degrees c, using standard homonuclear 1h nmr spectroscopy at 900mhz and the automated structure calculation software atnos/candid/dyana. the automatic noesy spectral a ... | 2005 | 16185738 |
| 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 |
| arterial acid-base status during digestion and following vascular infusion of nahco(3) and hcl in the south american rattlesnake, crotalus durissus. | digestion is associated with gastric secretion that leads to an alkalinisation of the blood, termed the "alkaline tide". numerous studies on different reptiles and amphibians show that while plasma bicarbonate concentration ([hco(3)(-)](pl)) increases substantially during digestion, arterial ph (pha) remains virtually unchanged, due to a concurrent rise in arterial pco(2) (paco(2)) caused by a relative hypoventilation. this has led to the suggestion that postprandial amphibians and reptiles regu ... | 2005 | 16289770 |
| isolation of a new l-amino acid oxidase from crotalus durissus cascavella venom. | a novel l-amino acid oxidase (lao) (casca lao) from crotalus durissus cascavella venom was purified to a high degree of molecular homogeneity using a combination of molecular exclusion and ion-exchange chromatography system. the purified monomer of lao presented a molecular mass of 68 kda and pi estimated in 5.43, which were determined by two-dimensional electrophoresis. the 71st n-terminal amino acid sequence of the lao from crotalus durissus cascavella presented a high amino acid sequence simi ... | 2006 | 16307769 |
| 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 |
| lipoxygenase-derived eicosanoids are involved in the inhibitory effect of crotalus durissus terrificus venom or crotoxin on rat macrophage phagocytosis. | crotalus durissus terrificus snake venom and its major toxin, crotoxin or type ii pla2 subunit of this toxin, induce an inhibitory effect on spreading and phagocytosis in 2h incubated macrophages. the involvement of arachidonate-derived mediators on the inhibitory action of the venom or toxins on rat peritoneal macrophage phagocytosis was presently investigated. peritoneal cells harvested from naive rats and incubated with the venom or toxins or harvested from the peritoneal cavity of rats pre-t ... | 2006 | 16373074 |
| in vitro effects of crotalus durissus terrificus and bothrops jararaca venoms on giardia duodenalis trophozoites. | considering the snake venoms' pharmacological properties and chemotherapeutic potential as well as the need for new alternatives for giardia infection treatment, the present study was carried out aiming to evaluate the in vitro effects of crude crotalus durissus terrificus and bothrops jararaca venoms on the growth and adherence of giardia duodenalis trophozoites. trophozoites (10(6)) were exposed to serial twofold dilutions of c. durissus terrificus and b. jararaca venoms that ranged from 3.125 ... | 2006 | 16378220 |
| effects of crotalus durissus collilineatus venom in the isolated rat kidney. | ophidian accidents caused by the subspecies crotalus durissus are responsible for high morbity and mortality rates. acute renal failure is a common complication observed in these accidents. the aim of the present study was to investigate the renal effects promoted by the venom of c. d. collilineatus and its fractions, crotoxin and phospholipase a2. c. d. collilineatus (cdc; 30 microg ml(-1)), crotoxin (ctx; 10 microg ml(-1)) and phospholipase a2 (pla2; 10 microg ml(-1)) were tested in isolated r ... | 2006 | 16427672 |
| crotalus durissus terrificus venom interferes with morphological, functional, and biochemical changes in murine macrophage. | crotalus durissus terrificus venom (cdt) is toxic for a variety of eukaryotic cells, especially at high concentrations. however its effects on host immune cells are not well known. the purpose of this study was to determine the effect of cdt on functional status and the mediators production in peritoneal macrophages. the effects of cdt were analyzed in vitro and were detected using functional status of macrophages as determined by the h(2)o(2) release, spreading percentage, phagocytic index, vac ... | 2005 | 16489255 |
| crotacetin, a novel snake venom c-type lectin homolog of convulxin, exhibits an unpredictable antimicrobial activity. | snake venom (sv) c-type lectins encompass a group of hemorrhagic toxins that are capable of interfering with blood stasis. a very well-studied svc-type lectin is the heterodimeric toxin, convulxin (cvx), from the venom of south american rattlesnake crotalus durissus terrificus. cvx is able to activate platelets and induce their aggregation by acting via p62/gpvi collagen receptor. by using polymerase chain reaction homology screening, we have cloned several cdna precursors of cvx subunit homolog ... | 2006 | 16679528 |
| effect of multimer size and a natural dimorphism on the binding of convulxin to platelet glycoprotein (gp)vi. | convulxin (cvx), a c-type lectin from the venom of crotalus durissus terrificus, is a potent activator of human platelets, binding predominantly to glycoprotein (gp)vi. native cvx is an octamer composed of four alphabeta-heterodimers [(alphabeta)(4)]. two different native sequences have been reported, one bearing lysine (k), the other glutamic acid (e), at beta chain residue 89, but the physiological relevance of this difference is unknown. | 2006 | 16689765 |
| gastroesophageal reflux in healthy subjects induced by two different species of chilli (capsicum annum). | although the ingestion of chilli has been associated with gastroesophageal reflux (ger) symptoms, there are no studies that have explored the effect of a chronic ingestion of different kinds of chilli with a variable content of capsaicin as a cause of ger. | 2006 | 16699276 |
| characterization of a new platelet aggregating factor from crotoxin crotalus durissus cascavella venom. | in this article we investigated the platelet aggregating activity of whole crotoxin and its subunits isolated from crotalus durissus cascavella venom. during the purification protocols of the venom, using hplc molecular exclusion, we detected the presence of two different serine protease activities in the gyroxin fraction, and another in the crotoxin fraction, which induced strong and irreversible platelet aggregation, in addition to blood coagulation. from crotoxin, we isolated pla2, crotapotin ... | 2006 | 16729248 |
| crotoxin induces actin reorganization and inhibits tyrosine phosphorylation and activity of small gtpases in rat macrophages. | crotoxin is the main neurotoxic component of crotalus durissus terrificus snake venom. previous work of our group demonstrated that this toxin or its phospholipase a(2) subunit inhibits macrophage spreading and phagocytosis. the phagocytic activity of macrophages is controlled by the rearrangement of actin cytoskeleton and activity of the small rho gtpases. the effect of crotoxin and its subunit on actin reorganization and tyrosine phosphorylation in rat peritoneal macrophages, during phagocytos ... | 2006 | 16737726 |
| human platelets activation by convulxin is accompanied by tyrosyl-phosphorylation of plcgamma2 and occurs independently of integrin alphaiibbeta3. | in the present report we show that convulxin (cvx), a c-type lectin from crotalus durissus terrificus venom, induces platelet agregation and phospholipase c (plc) activation by a protein tyrosine kinase (ptk)-dependent pathway. in addition, cvx stimulates a rapid increase in tyrosine phosphorylation of human platelet proteins with molecular masses of 40, 72/74, 78/80 and 120 kda, followed by dephosphorylation of some proteins. however, platelet aggregation was accompanied by the phosphorylation ... | 1998 | 16793699 |
| convulxin-induced platelet adhesion and aggregation: involvement of glycoproteins vi and iaiia. | the interaction of convulxin (cvx), a 72-kda glycoprotein isolated from the venom of crotalus durissus terrificus with human platelets has been studied. cvx at low concentrations (below 100 pm) induced platelet aggregation, dense body secretion and intracellular calcium mobilization which indicates that cvx is a potent activator of human platelets. cvx-induced platelet aggregation and secretion was inhibited by 6fl an anti-integrin alpha2beta1 monoclonal antibody that was without effect on calci ... | 1998 | 16793703 |
| evidence for a respiratory component, similar to mammalian respiratory sinus arrhythmia, in the heart rate variability signal from the rattlesnake, crotalus durissus terrificus. | autonomic control of heart rate variability and the central location of vagal preganglionic neurones (vpn) were examined in the rattlesnake (crotalus durissus terrificus), in order to determine whether respiratory sinus arrhythmia (rsa) occurred in a similar manner to that described for mammals. resting ecg signals were recorded in undisturbed snakes using miniature datalogging devices, and the presence of oscillations in heart rate (fh) was assessed by power spectral analysis (psa). this mathem ... | 2006 | 16809454 |
| opiate and acetylcholine-independent analgesic actions of crotoxin isolated from crotalus durissus terrificus venom. | the venom of crotalus durissus terrificus is reported to have analgesic activity and the administration of crotoxin (cro) to cancer patients is reported to reduce the consumption of analgesics. this study investigated the analgesia induced by cro and the effects of atropine and naloxone on the antinociceptive activity of cro in mice and rats. the results showed that cro at 66.5, 44.3 and 29.5microg/kg (ip) exhibited a dose-dependent analgesic action in mice using the hotplate and acetic acid wri ... | 2006 | 16857228 |
| distribution of (125)i-labeled crotamine in mice tissues. | crotamine is a strong basic polypeptide from crotalus durissus terrificus (cdt) venom composed of 42 amino acid residues tightly bound by three disulfide bonds. it causes skeletal muscle spasms leading to spastic paralysis of hind limbs in mice. the objective of this paper was to study the distribution of crotamine injected intraperitoneally (ip) in mice. crotamine was purified from cdt venom by gel filtration followed by ion exchange chromatography, using a fast-performance liquid chromatograph ... | 2006 | 16919696 |
| a novel peptide from the acei/bpp-cnp precursor in the venom of crotalus durissus collilineatus. | in crotaline venoms, angiotensin-converting enzyme inhibitors [aceis, also known as bradykinin potentiating peptides (bpps)], are products of a gene coding for an acei/bpp-c-type natriuretic peptide (cnp) precursor. in the genes from bothrops jararaca and gloydius blomhoffii, acei/bpp sequences are repeated. sequencing of a cdna clone from venom glands of crotalus durissus collilineatus showed that two aceis/bpps are located together at the n-terminus, but without repeats. an additional sequence ... | 2006 | 16979945 |
| microvesicles in the venom of crotalus durissus terrificus (serpentes, viperidae). | microvesicles with electron-dense content are consistently observed by transmission electron microscopy on the luminal face of secretory cells of venom glands of viperid snakes. in this work, we evaluated their presence in crotalus durissus terrificus venom glands and also in freshly collected venom. microvesicles were found in the venom glands mainly in regions of exocytosis. they ranged from 40 to 80 nm in diameter. freeze-fracture replicas of the glands revealed particles on the cytoplasmic l ... | 2007 | 17084429 |
| the effect of treatment with crotapotin on the evolution of experimental autoimmune neuritis induced in lewis rats. | biomedical research in which venom components are being investigated for their potential as novel therapeutic agents has emerged as an interesting option. crotapotin, which is purified from the venom of the rattlesnake crotalus durissus terrificus, has been described as an anti-inflammatory agent that acts on the innate arm of the immune response. here we have demonstrated that intraperitoneal administration of crotapotin significantly reduces the severity of experimental autoimmune neuritis (ea ... | 2007 | 17145071 |
| withdrawn: microvesicles in the venom of crotalus durissus terrificus (serpentes, viperidae). | the publisher regrets that this article was an accidental duplication of an article that has already been published in toxicon, 49 (2007) 106-110, . the duplicate article has therefore been withdrawn. | 2006 | 17161856 |
| biological and structural characterization of crotoxin and new isoform of crotoxin b pla(2) (f6a) from crotalus durissus collilineatus snake venom. | a new crotoxin b isoform pla(2) (f6a), from crotalus durissus collilineatus was purified from by one step reverse phase hplc chromatography using mu-bondapack c-18 column analytic. the new crotoxin b isoform pla(2) (f6a), complex crotoxin, the catalytic subunit crotoxin b isoform pla(2) (f6a) and two crotapotin isoforms (f3 and f4), were isolated from the venom of crotalus durissus collilineatus. the crotapotins isoforms f3 and f4 had similar chemical properties, the two proteins different in th ... | 2007 | 17203389 |
| isolation and biochemical characterization of a galactoside binding lectin from bauhinia variegata candida (bvcl) seeds. | a new lectin (bvcl) from seeds of a primitive brazilian caesalpinoideae, the bauhinia variegata candida was purified and biochemical characterized. bvcl was isolated by gel filtration chromatography on sephadex g75 and affinity chromatography on immobilized d: -lactose column. sds-page showed that bvcl under non-reducing condition presents two bands of 68 and 32 kda and a single band of 32 kda in reducing condition. however, only one band was seen in native page. the hemagglutination activity of ... | 2007 | 17203390 |
| biochemical, pharmacological and structural characterization of two pla2 isoforms cdr-12 and cdr-13 from crotalus durissus ruruima snake venom. | cdr-12 and cdr-13 isoforms of pla2, a d49 protein, were purified from crotalus durissus ruruima venom after one chromatographic step, reverse phase hplc on micro-bondapack c-18. the molecular mass by sds-page of cdr-12 and cdr-13 isoforms of pla2 was 14333.49 da and 14296.42 da, respectively and confirmed by maldi-tof mass spectrometry. the amino acid composition showed that both isoforms cdr-12 and cdr-13 have a high content of lys, tyr, gly, arg, and 14 half-cys residues, typical of a basic pl ... | 2007 | 17203396 |
| chromatin supraorganization, dna fragmentation, and cell death in erythrocytes of the rattlesnake, crotalus durissus terrificus (serpentes, viperidae), infected with the protozoan, hepatozoon spp. (apicomplexa, hepatozoidae). | forms of the protozoan of the hepatozoon genus are detected free in the circulation and also within some of the erythrocytes of infected snakes. in healthy snakes, dna fragmentation and cell death usually affect a few circulating erythrocytes in agreement with the long life span expected for these cells. in the present study we investigated whether infection by hepatozoon spp. affected the incidence of dna fragmentation and cell death in erythrocytes from the rattlesnake, crotalus durissus terri ... | 2007 | 17208020 |
| rabbit igg antibodies against phospholipase a2 from crotalus durissus terrificus neutralize the lethal activity of the venom. | crotalus durissus terrificus (c.d.t.) (south american rattlesnake) venom possesses myotoxic and neurotoxic activities, both of which are also expressed by crotoxin, the principal toxin of this venom. crotoxin contains a basic phospholipase a2 (pla2) and a non toxic acidic protein, crotapotin. we have produced and investigated the ability of igg antibodies raised in rabbits against pla2 to neutralize the lethality of the whole venom. pla2 was isolated by gel filtration chromatography (sephadex g- ... | 2006 | 17240621 |
| bothrops jararaca and crotalus durissus terrificus venoms elicit distinct responses regarding to production of prostaglandins e2 and d2, and expression of cyclooxygenases. | prostaglandins (pgs), synthesized by cyclooxygenases, play important roles in many pathophysiological processes including inflammation and hyperalgesia. in this study the profiles of pge(2) and pgd(2) production secondary to injection of bothrops jararaca venom (bjv), with inflammatory activity or crotalus durissus terrificus venom (cdtv), with anti-inflammatory and antinociceptive properties, into mice were evaluated, and the ability of these venoms to induce expression of cyclooxygenases-1 (co ... | 2007 | 17241651 |
| long-lasting anti-inflammatory properties of crotalus durissus terrificus snake venom in mice. | in the present study, we investigated the effects of crotalus durissus terrificus venom (cdtv) on vascular and cellular events of inflammation induced by carrageenan (cg) in mice. to evaluate edema, cdtv (75 microg kg(-1)) was administered subcutaneously before (1h, 7 or 14 days) or after (1, 4 or 48 h) subplantar injection of cg (15 mg kg(-1)) into the mouse right hind paw; to analyze leukocyte influx, cg (200 microl) was injected i.p. in mice. the inhibitory action of cdtv on edema, either bef ... | 2007 | 17368497 |
| autophagy is involved in cytotoxic effects of crotoxin in human breast cancer cell line mcf-7 cells. | to investigate the role of crotoxin (crtx)-induced autophagy in the death of mcf-7 cells, a caspase-3-deficient, human breast cancer cell line. | 2007 | 17376294 |
| 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 |
| crystallization and preliminary x-ray crystallographic analysis of the heterodimeric crotoxin complex and the isolated subunits crotapotin and phospholipase a2. | crotoxin, a potent neurotoxin from the venom of the south american rattlesnake crotalus durissus terrificus, exists as a heterodimer formed between a phospholipase a(2) and a catalytically inactive acidic phospholipase a(2) analogue (crotapotin). large single crystals of the crotoxin complex and of the isolated subunits have been obtained. the crotoxin complex crystal belongs to the orthorhombic space group p2(1)2(1)2, with unit-cell parameters a = 38.2, b = 68.7, c = 84.2 a, and diffracted to 1 ... | 2007 | 17401196 |
| neurotoxicological effects of a thrombin-like enzyme isolated from crotalus durissus terrificus venom (preliminary study). | a thrombin-like enzyme, purified from the venom of crotalus durissus terrificus by gel filtration and affinity chromatography, showed a single protein band in sodium dodecyl sulfate-polyacrilamide gel electrophoresis (sds-page) with a molecular weight of about 33kda. clear cellular morphological changes, deep ganglioside level modifications in some brain areas and behavioral alterations in pup rats injected with this protein were detected. ganglioside composition, one of the chemical markers of ... | 2007 | 17467764 |
| individual venom variability in the south american rattlesnake crotalus durissus cumanensis. | crotalus durissus cumanensis snake venoms from different venezuelan regions, showed biochemical and hemostatic variations. fibrino(geno)lytic, hemorrhagic and procoagulant activities and gel-filtration chromatography and sds-page profiles were analyzed. differences were observed in fibrinolytic activity: kallikrein-like amidolytic activity was highest in venoms of santa teresa, and margarita. lagunetica and carrizales venoms showed the maximum fibrin lysis. the highest hemorrhagic activity was s ... | 2007 | 17482229 |
| crotamine mediates gene delivery into cells through the binding to heparan sulfate proteoglycans. | recently we have shown that crotamine, a toxin from the south american rattlesnake crotalus durissus terrificus venom, belongs to the family of cell-penetrating peptides. moreover, crotamine was demonstrated to be a marker of centrioles, of cell cycle, and of actively proliferating cells. herein we show that this toxin at non-toxic concentrations is also capable of binding electrostatically to plasmid dna forming dna-peptide complexes whose stabilities overcome the need for chemical conjugation ... | 2007 | 17491023 |
| crotamine inhibits preferentially fast-twitching muscles but is inactive on sodium channels. | crotamine is a peptide toxin from the venom of the rattlesnake crotalus durissus terrificus that induces a typical hind-limb paralysis of unknown nature. hind limbs have a predominance of fast-twitching muscles that bear a higher density of sodium channels believed until now to be the primary target of crotamine. hypothetically, this makes these muscles more sensitive to crotamine and would explain such hind-limb paralysis. to challenge this hypothesis, we performed concentration vs. response cu ... | 2007 | 17588630 |
| alterations in the ultrastructure of cardiac autonomic nervous system triggered by crotoxin from rattlesnake (crotalus durissus cumanensis) venom. | this study explored the toxic effects of crotoxin isolated from crotalus durissus cumanensis venom on the ultrastructure of mice cardiac autonomic nervous system. mice were intravenously injected with saline (control group) and crotoxin diluted in saline venom (study group) at a dose of 0.107 mg/kg mouse body weight. samples from the inter-ventricular septum were prepared for electron microscopy after 6 h (g1), 12 h (g2), 24 h (g3) and 48 h (g4). the g1 group showed some cardiomyocyte with pleom ... | 2007 | 17616380 |
| comparative studies of the anti-leishmanial activity of three crotalus durissus ssp. venoms. | in this study, we compared the anti-leishmanial activity of three crotalic venoms (crotalus durissus terrificus-cdt, crotalus durissus cascavella-cdca, and crotalus durissus collilineatus-cdcol). different concentrations of each venom incubated with leishmania (leishmania) amazonensis promastigotes were used. cdt venom exhibited a higher anti-leishmanial activity (inhibitory concentration-ic50-value of 4.70+/-1.72 microg/ml) in comparison with that of cdca venom (ic50 value of 9.41+/-1.21 microg ... | 2007 | 17659386 |
| the adrenergic regulation of the cardiovascular system in the south american rattlesnake, crotalus durissus. | the present study investigates adrenergic regulation of the systemic and pulmonary circulations of the anaesthetised south american rattlesnake, crotalus durissus. haemodynamic measurements were made following bolus injections of adrenaline and adrenergic antagonists administered through a systemic arterial catheter. adrenaline caused a marked systemic vasoconstriction that was abolished by phentolamine, indicating this response was mediated through alpha-adrenergic receptors. injection of phent ... | 2007 | 17669676 |
| the use of zootherapeutics in folk veterinary medicine in the district of cubati, paraíba state, brazil. | the present work addresses the use of zootherapy in folk veterinary medicine (ethnoveterinary) by the residents of the municipal district of cubati, microregion of seridó, paraíba state, brazil. it sought to identify the principal animals used as medicinal sources for zootherapeutics and to contribute to the preservation and sustainability of this traditional knowledge. | 2007 | 17825094 |
| structural and biological characterization of two crotamine isoforms iv-2 and iv-3 isolated from the crotalus durissus cumanensis venom. | in this work, we isolated the two new crotamine isoforms from the crotalus durissus cumanensis rattlesnake venom and its "in vitro" neurotoxic, myotoxic and lethality (dl(50)) intracerebroventricular (i.c.v.) effects were characterized. these proteins were named iv-2 and iv-3 and were purified by combination of two chromatographic steps on molecular exclusion chromatography on superdex 75 and reverse phase hplc (mu-bondapack c18). the molecular mass of the crotamine isoforms was 4905.96 da for i ... | 2007 | 17828447 |
| inhibitory effect of crotoxin on the pain-evoked discharge of neurons in thalamic parafascicular nucleus in rats. | crotoxin (cro), the principal neurotoxic component of crotalus durissus terrificus, has been previously reported to have a behavioral analgesic effect in rats and mice. the present study investigated electrophysiologically the effect of cro on pain-evoked unit discharge of neurons in thalamic parafascicular nucleus (pf) and underlying mechanisms of its effect. the electrical discharge of pf neurons was recorded with the microelectrode technique in rats. intracerebroventricular (i.c.v.) injection ... | 2008 | 17915276 |
| ability of rabbit antiserum against crotapotin to neutralize the neurotoxic, myotoxic and phospholipase a2 activities of crotoxin from crotalus durissus cascavella snake venom. | the toxicity of crotoxin, the major toxin of crotalus durissus terrificus (south american rattlesnake) venom, is mediated by its basic phospholipase a(2) (pla(2)) subunit. this pla(2) is non-covalently associated with crotapotin, an acidic, enzymatically inactive subunit of the crotoxin complex. in this work, rabbit antiserum raised against crotapotin purified from crotalus durissus cascavella venom was tested for its ability to neutralize the neurotoxicity of this venom and its crotoxin in vitr ... | 2008 | 17920236 |
| identification of proteins similar to bothrops jararaca coagulation inhibitor (bji) in the plasmas of bothrops alternatus, bothrops jararacussu and crotalus durissus terrificus snakes. | bothrops jararaca coagulation inhibitor (bji), a protein isolated from b. jararaca plasma, specifically inhibits the coagulant activity of thrombin. our group previously identified proteins similar to bji in the plasma of other snakes [tanaka-azevedo, a.m., tanaka, a.s., sano-martins i.s., 2003. a new blood coagulation inhibitor from the snake bothrops jararaca plasma: isolation and characterization. biochem biophys res commun 308, 706-712.]. in the present study, we analyzed the presence of bji ... | 2008 | 17931922 |
| preliminary x-ray crystallographic studies of a tetrameric phospholipase a2 formed by two isoforms of crotoxin b from crotalus durissus terrificus venom. | crotoxin b is a basic phospholipase a2 found in the venom of crotalus durissus terrificus and is one of the subunits that constitute crotoxin. this heterodimeric toxin, which is the main component of c. d. terrificus venom, is completed by an acidic, nontoxic and non-enzymatic component (crotoxin a) and is involved in important envenomation effects, such as neurological disorders, myotoxicity and renal failure. although crotoxin was first crystallized in 1938, no crystal structure is currently a ... | 2007 | 18084096 |
| the effect of phospholipase a2 from crotalus durissus collilineatus on leishmania (leishmania) amazonensis infection. | in this study, the effect of phospholipase a2 (pla2) derived from crotalus durissus collilineatus was evaluated in vitro and in vivo on experimental cutaneous leishmaniasis. the promastigote and amastigote forms treated with pla2 presented increased growth rate. in vivo studies showed that pla2-treated leishmania (leishmania) amazonensis promastigotes increased the size of lesions in balb/c mice, and histopathological analysis showed numerous necrotic regions presenting a higher density of polym ... | 2008 | 18180953 |
| peptide fingerprinting of snake venoms by direct infusion nano-electrospray ionization mass spectrometry: potential use in venom identification and taxonomy. | fingerprinting by mass spectrometry has been increasingly used to study venom variations and for taxonomic analyses based on venom components. most of these studies have concentrated on components heavier than 3 kda, but bothrops snake venoms contain many biologically active peptides, principally c-type natriuretic peptides and bradykinin-potentiating peptides (bpps). in this work, we have examined the peptide profile of bothrops venoms (b. alternatus, b. erythromelas, b. insularis, b. jararaca, ... | 2008 | 18200607 |
| insights into the role of oligomeric state on the biological activities of crotoxin: crystal structure of a tetrameric phospholipase a2 formed by two isoforms of crotoxin b from crotalus durissus terrificus venom. | crotoxin b (cb or cdt pla(2)) is a basic asp49-pla(2) found in the venom of crotalus durissus terrificus and it is one of the subunits that constitute the crotoxin (cro). this heterodimeric toxin, main component of the c. d. terrificus venom, is completed by an acidic, nontoxic, and nonenzymatic component (crotoxin a, ca or crotapotin), and it is related to important envenomation effects such as neurological disorders, myotoxicity, and renal failure. although cro has been crystallized since 1938 ... | 2008 | 18275084 |
| phylogeny of snake trypanosomes inferred by ssu rdna sequences, their possible transmission by phlebotomines, and taxonomic appraisal by molecular, cross-infection and morphological analysis. | blood examination by microhaematocrit and haemoculture of 459 snakes belonging to 37 species revealed 2.4% trypanosome prevalence in species of viperidae (crotalus durissus and bothrops jararaca) and colubridae (pseudoboa nigra). trypanosome cultures from c. durissus and p. nigra were behaviourally and morphologically indistinguishable. in addition, the growth and morphological features of a trypanosome from the sand fly viannamyia tuberculata were similar to those of snake isolates. cross-infec ... | 2008 | 18371240 |
| minimal volume regulation after shrinkage of red blood cells from five species of reptiles. | red blood cells (rbcs) from most vertebrates restore volume upon hypertonic shrinkage and the mechanisms underlying this regulatory volume increase (rvi) have been studied extensively in these cells. despite the phylogenetically interesting position of reptiles, very little is known about their red cell function. the present study demonstrates that oxygenated rbcs in all major groups of reptiles exhibit no or a very reduced rvi upon approximately 25% calculated hyperosmotic shrinkage. thus, rbcs ... | 2008 | 18424207 |
| crotoxin alters lymphocyte distribution in rats: involvement of adhesion molecules and lipoxygenase-derived mediators. | crotoxin is the main neurotoxic component of crotalus durissus terrificus snake venom and modulates immune and inflammatory responses, interfering with the activity of leukocytes. in the present work, the effects of crotoxin on the number of blood and lymphatic leukocytes and on lymph nodes and spleen lymphocytes population were investigated. the toxin s.c. administered to male wistar rats, decreases the number of lymphocytes in blood and lymph circulation and increases the content of b and t-ly ... | 2008 | 18452962 |