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Made available in DSpace on 2020-12-12T02:25:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-04-20 BIOMOLPEP, Instituto de Biociências, UNESP, Campus do Litoral Paulista, São Vicente, São Paulo, Brazil; LABIMES, Instituto de Biociências, UNESP, Campus do Litoral Paulista, São Vicente, São Paulo, Brazil; UNESP CLP, Brazil

The venom of Crotalus durissus terrificus produces a neurotoxic and myotoxic syndrome that can lead to the death. Specific antivenom is the only treatment to neutralize the toxicity of the venom and the precocity in applying the antivenom is crucial for the efficiency of the treatment. We studied the variation of the immunochemical reactivity and neutralizing capacity of the specific antivenom on this venom in pre-incubation and rescue experiments, at different times. ELISA titers increased with longer venom-antivenom incubation times (p < 0.05) nevertheless incubation times had no effect on the neutralizing capacity of the antivenom. The antivenom dose necessary to rescue mice injected with 1.5 MMD (minimal mortal dose) 30 min after venom inoculation was over ten folds the dose of antivenom theoretically required to neutralize the same dose of venom according values obtained from pre-incubation experiments. Results showed that the in vitro immunochemical reactivity is not directly related to the neutralizing capacity. These observations underline the need for a rapid antivenom administration. Although preincubation experiments in mice are a powerful tool for the validation of the potency of the antivenoms in the productive process, it is clear that the nominal neutralization of the antivenoms must not be considered as a “stoichiometric” value regarding the venom to be neutralized in case of natural envenomation and emphasize the need of realization of clinical trials in order to evaluate the adequate doses of antivenom to be therapeutically used. Fil: Baudou, Federico Gastón. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Litwin, Silvana. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Lanari, Laura Cecilia. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Laskowicz, Rodrigo Daniel. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina Fil: Damin, Carlos Fabian. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Chippaux, Jean-Philippe. Universite de Paris I Pantheon - Sorbonne; Francia Fil: de Roodt, Adolfo Rafael. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentina

Made available in DSpace on 2020-12-12T02:25:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-04-20 Interunidades em Biotecnologia, USP, São Paulo, São Paulo, Brazil; Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, CEP 05508-090, São Paulo, São Paulo, Brazil; BIOMOLPEP, Instituto de Biociências, UNESP, Campus do Litoral Paulista, São Vicente, São Paulo, Brazil; LABIMES, Instituto de Biociências, UNESP, Campus do Litoral Paulista, São Vicente, São Paulo, Brazil; UNESP CLP, Brazil

This study evaluated cellular and molecular effects of radicicol, a heat shock protein (HSP) inducer, on the regeneration of skeletal muscle injured by crotoxin, the main toxin isolated from Crotalus durissus terrificus venom. Regenerating muscles treated with radicicol had decreased NF-kB activation. Differentiating myoblasts treated with radicicol showed reduced number of NF-kB positive nuclei and increased fusion index. The results suggest that radicicol enhances regeneration of muscle by attenuating NF-kB activation and increasing myogenic differentiation.

Antivenoms are usually obtained by animal immunization with successive inoculations of increasing sublethal amounts of venom, which may impair the animal health. The high lethality of venom requires prolonged immunization plans with small amounts of venom. Thus, we propose an alternative plan that includes a pre-immunization of the animal with phospholipase A 2 , the main crotoxin component, which is responsible for the whole venom lethality. For comparison, three different immunization schemes were designed: high dose protocol (HDP; 0.5–27 mg of venom), low dose protocol (LDP; 0.1–7 mg of venom) and Mix protocol (MP; preimmunization 0.1–1.2 mg of crotalic PLA 2 , and then 4.5–8 mg of venom). Antibody titers were determined by ELISA, in blood plasma obtained from the marginal vein of the ear. The neutralizing ability of the different sera obtained by all protocols (HDS, LDS and MS) was tested against the most important pharmacological activities of whole venom: PLA 2 activity, myotoxicity, thrombin like activity and lethality. MS showed the best neutralizing efficacy and at the same time, it was obtained by an immunization protocol that takes account of animal health care, since it requires low quantities of venoms in comparison to traditional protocols.

Cross-neutralization of Crotalus durissus terrificus venom coagulant activity was tested using bivalent horse antivenom against Bothrops alternatus and Bothrops diporus venoms. Our in vitro and in vivo experiments showed that bothropic antivenom neutralizes the thrombin-like activity of crotalic snake venom and this cross-reaction was demonstrated by immunoassays either with whole venom or a purified thrombin-like enzyme. These results suggest common antigenic properties and, consequently, similar molecular structure among venom thrombin-like enzymes. Besides, they provide information that could be further used in the development of new antivenom formulations.

The basic knowledge on neoplasms is increasing quickly; however, few advances have been achieved in clinical therapy against tumors. For this reason, the development of alternative drugs is relevant in the attempt to improve prognosis and to increase patients' survival. Snake venoms are natural sources of bioactive substances with therapeutic potential. The objective of this work was to identify and characterize the antitumoral effect of Crotalus durissus terrificus venom (CV) and its polypeptide, crotoxin, on benign and malignant tumors, respectively, pituitary adenoma and glioblastoma. The results demonstrated that CV possess a powerful antitumoral effect on benign (pituitary adenoma) and malignant (glioblastoma multiforme) tumors with IC50 values of 0.96 ± 0.11 µg/mL and 2.15 ± 0.2 µg/mL, respectively. This antitumoral effect is cell-cycle-specific and dependent on extracellular calcium, an important factor for crotoxin phospholipase A2 activity. The CV antitumoral effect can be ascribed, at least partially, to the polypeptide crotoxin that also induced brain tumor cell death. In spite of the known CV nephrotoxicity and neurotoxicity, acute treatment with its antitumoral dose established in vitro was not found to be toxic to the analyzed animals. These results indicate the biotechnological potential of CV as a source of pharmaceutical templates for cancer therapy.

Background Crotalus durissus terrificus venom (CdtV) is one of the most studied snake venoms in Brazil. Despite presenting several well known proteins, its L-amino acid oxidase (LAAO) has not been studied previously. This study aimed to isolate, characterize and evaluate the enzyme stability of bordonein-L, an LAAO from CdtV. Methods The enzyme was isolated through cation exchange, gel filtration and affinity chromatography, followed by a reversed-phase fast protein liquid chromatography to confirm its purity. Subsequently, its N-terminal amino acid sequence was determined by Edman degradation. The enzyme activity and stability were evaluated by a microplate colorimetric assay and the molecular mass was estimated by SDS-PAGE using periodic acid-Schiff staining and determined by mass spectrometry. Results The first 39 N-terminal amino acid residues exhibited high identity with other snake venom L-amino acid oxidases. Bordonein-L is a homodimer glycoprotein of approximately 101 kDa evaluated by gel filtration. Its monomer presents around 53 kDa estimated by SDS-PAGE and 58,702 Da determined by MALDI-TOF mass spectrometry. The enzyme exhibited maximum activity at pH 7.0 and lost about 50 % of its activity after five days of storage at 4 °C. Bordonein-L’s activity was higher than the control when stored in 2.8 % mannitol or 8.5 % sucrose. Conclusions This research is pioneering in its isolation, characterization and enzyme stability evaluation of an LAAO from CdtV, denominated bordonein-L. These results are important because they increase the knowledge about stabilization of LAAOs, aiming to increase their shelf life. Since the maintenance of enzymatic activity after long periods of storage is essential to enable their biotechnological use as well as their functional studies.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:43:32Z No. of bitstreams: 1 S1678-91992006000200010.pdf: 116811 bytes, checksum: bb3cb3b8f9104998c7434d2686c36001 (MD5) Made available in DSpace on 2013-08-22T18:43:32Z (GMT). No. of bitstreams: 1 S1678-91992006000200010.pdf: 116811 bytes, checksum: bb3cb3b8f9104998c7434d2686c36001 (MD5) Previous issue date: 2006-04-01 Made available in DSpace on 2013-09-30T19:31:12Z (GMT). No. of bitstreams: 2 S1678-91992006000200010.pdf: 116811 bytes, checksum: bb3cb3b8f9104998c7434d2686c36001 (MD5) S1678-91992006000200010.pdf.txt: 25881 bytes, checksum: 1a1c2168e238b5674e61a3b32fd42553 (MD5) Previous issue date: 2006-04-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:08:33Z No. of bitstreams: 2 S1678-91992006000200010.pdf: 116811 bytes, checksum: bb3cb3b8f9104998c7434d2686c36001 (MD5) S1678-91992006000200010.pdf.txt: 25881 bytes, checksum: 1a1c2168e238b5674e61a3b32fd42553 (MD5) Made available in DSpace on 2014-05-20T15:08:33Z (GMT). No. of bitstreams: 2 S1678-91992006000200010.pdf: 116811 bytes, checksum: bb3cb3b8f9104998c7434d2686c36001 (MD5) S1678-91992006000200010.pdf.txt: 25881 bytes, checksum: 1a1c2168e238b5674e61a3b32fd42553 (MD5) Previous issue date: 2006-04-01 The present work aimed to evaluate the clinical and hematological aspects during experimental envenomation by Crotalus durissus terrificus in dogs treated with different antiophidic serum doses. Sixteen dogs were divided into two groups of eight animals each. Group I received 1mg/kg venom subcutaneously and 30mg antiophidic serum intravenously; Group II received 1mg/kg venom subcutaneously and 60mg antiophidic serum intravenously. In the clinical evaluation, we observed ataxia, moderate sedation, dilated pupils, sialorrhea, flaccid paralysis of mandibular muscles, and discreet edema at the site of venom inoculation. Evaluating red and white blood cells, we observed a decrease of hemoglobins, globular volume and erythrocytes, and an increase of plasmatic proteins, leukocytes, neutrophils, monocytes and lymphocytes. Clotting time increased and there was blood incoagulability with return to normal clotting time six hours after antiophidic serum administration. Animals treated with six antiophidic serum flasks had a faster recovery than the animals that received three serum flasks. UNOESTE Medical Clinic Department of Small Animals UNESP School of Veterinary Medicine and Animal Husbandry Department of Small Animals, Medical Clinic UNESP School of Veterinary Medicine and Animal Husbandry Department of Small Animals, Medical Clinic

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 on the chemistry of coffee. In 1938 Slotta and his brother-in-law Heinz Fraenkel-Conrat isolated crotoxin from Crotalus durissus terrificus venom, the first snake toxin to be obtained in crystalline form. They had evidence to suggest that the toxicity of crotoxin was due to a phospholipolytic action on nerve lipids. In 1938 Slotta's department was closed; he subsequently co-founded a biopharmaceutical company. In 1956 Slotta was appointed research professor of biochemistry at the University of Miami, USA. Slotta purified the most basic polypeptide from Naja naja venom, known as direct lytic factor, and with James Vick identified this as cardiotoxin. Karl H. Slotta will be remembered not only for his skill as a biochemist but also for his indomitable and cheerful spirit.

Made available in DSpace on 2021-07-14T10:38:19Z (GMT). No. of bitstreams: 0 Previous issue date: 1998 The objective of this study was to evaluate the effects of the thrombin-like fraction of Crotalus durissus terrificus venom, Reptilase , and bovine thrombin of fibrinogen pools on bovine, equine, ovine, bubaline and human cryoprecipitates. The authors also made a comparative study between animal and human cryoprecipitates to see if any there was any possibility of future use in medicine. Fibrinogen levels in cryoprecipitate were studied using 48 blood samples obtained as follows:12 samples from humans, 9 from bovine, 10 from equine, 10 from ovine and 7 from bubaline. The results obtained showed average levels of 375.50 mg % for humans, 218.33 mg % for bovine, 240.80 mg % for equine, 267.70 mg % for ovine and 664.00 mg % for bubaline. Upon the formation of pools of human and animal fibrinogens, the following results were obtained: 435 mg % for humans, 444 mg % for bovine, 337 mg % for equine, 390 mg % for ovine and 530 mg % for bubaline. Statistical analysis (using the analysis of variance for entirely randomized experiment for the calculation of F statistics) demonstrated that the bubaline fibrinogen level was higher than that of human, and both were higher than those of ovine, equine, and bovine. Clotting times were determined using different dilutions of bovine thrombin, thrombin-like fraction of Crotalus durissus terrificus venom, and Reptilase . Comparing these clotting times, results for human and bovine were found to be very similar, whereas using equine, ovine, and bubaline the results above a dilution of 1:3 were markedly different. The results obtained permitted the following conclusions to be drawn show that: 1) bovine thrombin presented better interactivity with fibrinogen extracted both from human and bovine cryoprecipitates; 2) there was similar behavior when bovine thrombin was substituted for Reptilase and for the thrombin-like fraction of Crotalus durissus terrificus venom; 3) cryoprecipitate from bovine can, in special circumstances, substitute human cryoprecipitate in medical practice; 4) human and bovine cryoprecipitates can be used with both Reptilase and Crotalus durissus terrificus fractions using a dilution up to 1:5; 5) the use of bovine cryoprecipitate can be recommended using either bovine thrombin, Reptilase , or thrombin-like fraction of Crotalus durissus terrificus venom. Departament of Tropical Diseases School of Medicine of Botucatu, Laboratory of Hemostasis of the Blood Bank School of Pharmaceutical Sciences of Araraquara, Laboratory of Micology UNESP, Center for the Study of Venoms and Venomous Animals - CEVAP UNESP, Center for the Study of Venoms and Venomous Animals - CEVAP

In the present study, we demonstrate that the volumes in which a given protein mass of Crotalus durissus terrificus venom or of a lyophilized stabilized aqueous extract (LSAE) of Peschiera fuchsiaefolia, an antivenom agent injected intramuscularly, have a decisive influence on the results. The LD50 of C. d. terrificus venom injected i.m. in a final volume of 200µl (2µl/g) (saline solution, 0.9% NaCl) was 180µg/100g rat body weight (p

very sensitive method for estimating the concentration of crotamine in a solution was developed. This method was based on the time required for the appearance of permanent hyperextension of the rear legs of mice as a function of the dose administered. This method can be used to determine toxin doses as low as 0.32 mg/kg . Its high specificity for crotamine means that it can be used to measure toxin concentrations in the presence of other proteins and polypeptides.

This work describes for the first time the characterization of the enzymatic features of gyroxin, a serine protease from Crotalus durissus terrificus venom, capable to induce barrel rotation syndrome in rodents. Measuring the hydrolysis of the substrate ZFR-MCA, the optimal pH for proteolytic cleavage of gyroxin was found to be at pH 8.4. Increases in the hydrolytic activity were observed at temperatures from 25 °C to 45 °C, and increases of NaCl concentration up to 1 M led to activity decreases. The preference of gyroxin for Arg residues at the substrate P1 position was also demonstrated. Taken together, this work describes the characterization of substrate specificity of gyroxin, as well as the effects of salt and pH on its enzymatic activity.

In this study, we investigated in groups of female BALB/c mice injected withCrotalus durissus terrificusvenom (Cdt) the renal function based on creatinine clearance, percentage of fractional excretion cytokines and histological examination of renal tissue.Cdtcaused renal alterations that induced proteinuria during the initial hours post-venom and reduced creatinine clearance 15 min. up to 2 hours post-venom administration. In urine from mice injected withCdtinduced a decrease in IL-4 levels. More pronounced increments of IL-5, IL-6 and IFN-γwere observed after 15 and 30 min, respectively. The highest levels of TNF and IL-10 were observed at 1 and 4 hs, respectively. The ratios of pro- and anti-inflammatory cytokines in animals injected withCdt, which may be manifested in the inflammatory status during the envenoming. In groups of animals treated withCdtwere observed a decreasing in creatinine clearance and its effect on glomerular filtration rate was accompanied by decreased fractional excretion of cytokines and morphologic disturbances. This loss of change selectively in envenomation could thus explain why the relatively excretion of cytokines is reduced while of total proteins increases. In conclusion the fractional excretion of cytokines is significantly reduced in mice injected withCdt, despite proteinuria.

The biological activities of ‘yellow’ and ‘white’ venom of a rattlesnake Crotalus durissus ruruima Hoge, 1965, found in the savanna-like vegetation (cerrado) of northern Brazil (Roraima) and Venezuela have been studied, and compared to the reference Crotalus durissus terrificus venom. The lethal activity of venoms depended on the inoculation route. The most toxic venom was the white one. The venoms of C. d. terrificus and the yellow of C. d. ruruima had similar lethalities. The yellow venom of C. d. ruruima showed a caseinolytic activity three times higher than that obtained with either the venom of C. d. terrificus or the white one of the C. d. ruruima . Hemorrhagic and necrotic activities were found only in the yellow venom. White and yellow venoms from C. d. ruruima showed a similar action on fibrinogen; this thrombin-like action was greater with C. d. terrificus venom. On histopathological sections local and pulmonary hemorrhage was found only with the yellow venom, but myonecrotic activity was observed with both venoms of C. d. ruruima . Among all antivenoms studied, the anti-bothropic-crotalic was the best at neutralizing hemorrhagic and hemolytic activities. These results suggest that antivenom bothropic-crotalic should be used in the treatment of patients with snakebite by C. d. ruruima : besides its neutralization on lethal activity, it also neutralizes the hemorrhagic activity present in some venoms.

The basic knowledge on neoplasms is increasing quickly; however, few advances have been achieved in clinical therapy against tumors. For this reason, the development of alternative drugs is relevant in the attempt to improve prognosis and to increase patients' survival. Snake venoms are natural sources of bioactive substances with therapeutic potential. The objective of this work was to identify and characterize the antitumoral effect of Crotalus durissus terrificus venom (CV) and its polypeptide, crotoxin, on benign and malignant tumors, respectively, pituitary adenoma and glioblastoma. The results demonstrated that CV possess a powerful antitumoral effect on benign (pituitary adenoma) and malignant (glioblastoma multiforme) tumors with IC50 values of 0.96 ± 0.11 µg/mL and 2.15 ± 0.2 µg/mL, respectively. This antitumoral effect is cell-cycle-specific and dependent on extracellular calcium, an important factor for crotoxin phospholipase A2 activity. The CV antitumoral effect can be ascribed, at least partially, to the polypeptide crotoxin that also induced brain tumor cell death. In spite of the known CV nephrotoxicity and neurotoxicity, acute treatment with its antitumoral dose established in vitro was not found to be toxic to the analyzed animals. These results indicate the biotechnological potential of CV as a source of pharmaceutical templates for cancer therapy.

Made available in DSpace on 2013-08-12T17:52:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-01-01 Made available in DSpace on 2013-09-30T17:42:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:12:52Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T13:12:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-01-01 The venom of Crotalus durissus terrificus snakes presents various substances, including a serine protease with thrombin-like activity, called gyroxin, that clots plasmatic fibrinogen and promote the fibrin formation. The aim of this study was to purify and structurally characterize the gyroxin enzyme from Crotalus durissus terrificus venom. For isolation and purification, the following methods were employed: gel filtration on Sephadex G75 column and affinity chromatography on benzamidine Sepharose 6B; 12% SDS-PAGE under reducing conditions; N-terminal sequence analysis; cDNA cloning and expression through RT-PCR and crystallization tests. Theoretical molecular modeling was performed using bioinformatics tools based on comparative analysis of other serine proteases deposited in the NCBI (National Center for Biotechnology Information) database. Protein N-terminal sequencing produced a single chain with a molecular mass of similar to 30 kDa while its full-length cDNA had 714 bp which encoded a mature protein containing 238 amino acids. Crystals were obtained from the solutions 2 and 5 of the Crystal Screen Kit (R), two and one respectively, that reveal the protein constitution of the sample. For multiple sequence alignments of gyroxin-like B2.1 with six other serine proteases obtained from snake venoms (SVSPs), the preservation of cysteine residues and their main structural elements (alpha-helices, beta-barrel and loops) was indicated. The localization of the catalytic triad in His57, Asp102 and Ser198 as well as S1 and S2 specific activity sites in Thr193 and Gli215 amino acids was pointed. The area of recognition and cleavage of fibrinogen in SVSPs for modeling gyroxin B2.1 sequence was located at Arg60, Arg72, Gln75, Arg81, Arg82, Lis85, Glu86 and Lis87 residues. Theoretical modeling of gyroxin fraction generated a classical structure consisting of two alpha-helices, two beta-barrel structures, five disulfide bridges and loops in positions 37, 60, 70, 99, 148, 174 and 218. These results provided information about the functional structure of gyroxin allowing its application in the design of new drugs. São Paulo State Univ, UNESP, Univ Estadual Paulista, Botucatu Med Sch,CEVAP, BR-18610307 Botucatu, SP, Brazil São Paulo State Univ, UNESP, Univ Estadual Paulista, Botucatu Med Sch,CEVAP, BR-18610307 Botucatu, SP, Brazil

We compared several pharmacological and enzymatic effects induced by 11 snake venoms from seven species, six of them from different geographic areas of Antioquia and Choco, north-west of Colombia, South America (Bothrops atrox, B. nasutus, B. schlegelii, B. punctatus, Lachesis muta, Micrurus mipartitus), and Crotalus durissus terrificus venom, from specimens captured in other provinces of the country (Tolima, Huila, Meta and Atlantico). Differences were observed in edema-forming, hemorrhage, defibrination, indirect hemolysis, myonecrosis, proteolysis and lethal activity between venoms from different genera or species, as well as according to the geographic area of origin in B. atrox and B. nasutus snake venoms. Bothrops venoms, in particular B. atrox and L. muta, produced major local effects. All of the venoms, including M. mipartitus, had myotoxic effects. The most defibrinating venoms were B. atrox, L. muta, B. punctatus and C. d. terrificus. All of the venoms had indirect hemolytic activity; the venom of M. mipartitus being greatest. The most lethal venoms were those of C. d. terrificus and M. mipartitus. Within Bothrops species, the venom of B. schlegelii was the least active in terms of local and systemic pathologic effects.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:24:33Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:41:13Z : No. of bitstreams: 1 2-s2.0-78149421826.pdf: 1381462 bytes, checksum: de9ad9d0b3960645486c36dca048dc3c (MD5) Made available in DSpace on 2014-05-27T11:24:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-01 The ELISA technique was used to evaluate and compare young ovine humoral immune response during crotalic antiserum production. Animals were clinically evaluated throughout this process, and the neutralizing capacity of antisera raised against natural (NV) and Cobalt-60 irradiated (IrV) venoms of Crotalus durissus terrificus (C.d.t.) was verified by means of in vitro challenges. Three groups of six animals each were used: G1 received NV; G2 was inoculated with IrV; and G3 was used as control. Animals received six immunizations during 84 days at 14-day intervals. ELISA of antibody profile showed significant difference (p

Ethanolic extract of leaves of Galactia glauscescens (GGE) at concentration of 100 and 500 microg/ml prevented the neuromuscular paralysis induced by Crotalus durissus terrificus venom on mouse phrenic nerve-diaphragm preparation.

Made available in DSpace on 2021-07-14T10:38:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2002 The objective of this study was to detect the presence of local edema and hemorrhage caused by Crotalus durissus terrificus envenoming using magnetic resonance imaging (MRI). Six patients bitten by Crotalus durissus terrificus snakes were treated at the Emergency Unit and Tropical Diseases Unit of Botucatu School of Medicine, UNESP, São Paulo State, Brazil. After receiving specific serotherapy, the patients were submitted to MR of the bite site. Post contrast T1 and T2 spin-echo MRI were obtained revealing the following lesions: edema associated with hemorrhage in subcutaneous and muscular tissue (n=3), edema in subcutaneous tissue (n=2), and perimuscular hemorrhage (n=1). In this study, MR demonstrated a local effect of Crotalus durissus terrificus envenoming in inducing edema and hemorrhage, mainly in muscular tissues and perimuscular areas. These results indicate that Crotalus durissus terrificus venom cause a local muscular tissue damage in human envenoming represented by edema and hemorrhage. Universidade Estadual Paulista, Center for the Study of Venoms and Venomous Animals Universidade Estadual Paulista, Botucatu School of Medicine Faculdade do Norte Paulista Universidade Estadual Paulista, Center for the Study of Venoms and Venomous Animals Universidade Estadual Paulista, Botucatu School of Medicine

Made available in DSpace on 2021-07-14T10:25:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-12 Universidade Estadual Paulista, Faculdade de Medicina de Botucatu Universidade Estadual Paulista, Faculdade de Medicina de Botucatu

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 terrificus venom and crotoxin were studied on glomerular filtration rate (GFR), urinary flow (UF), perfusion pressure (PP) and percentage sodium tubular transport (%TNa+). The infusion of Crotalus durissus terrificus venom (10 microg/ml) and crotoxin (10 microg/ml) increased GFR (control80 = 0.78 +/- 0.07, venom80 = 1.1 +/- 0.07, crotoxin80 = 2.0 +/- 0.05 ml g(-1) min(-1), P

This article describes the light and electron microscopic appearance of the rat myocardium at various time intervals after the administration of Crotalus durissus terrificus venom by intraperitoneal route. The crotalid envenomation produced small foci of myocardial necrosis scattered throughout the base of the ventricles. These lesions were predominantly perivascular and were associated with slight to moderate interstitial edema as well as infiltration of mononuclear cells and of a great number of mast cells. The first changes appeared 24 hours after envenomation and reached maximal severity after 4 days. By 8 days, the cardiac morphology was comparable to that of control animals except for small foci of interstitial fibrosis at the base of both ventricles-probably attributable to reabsorption of necrotic myofibers and healing-and a small number of degenerated myofibers. The main points concerning these findings are their preferential localization at the base of the heart and the association of the foci of myocytolytic necrosis with a large number of mast cells. On the basis of these data, although nonspecific, the mechanism of venom-induced myocardial damage is discussed. Moreover, these findings call attention to the potential cardiotoxic effect of crotalid poisoning in humans.

In the present work we report that susceptibility to Crotalus durissus terrificus venom: varies according to the strain of inbred mouse used. The s.c. LD50 for Balb/c and C57BI/6 mice were 193 micrograms/kg and 171 micrograms/kg, whereas for A/J and DBA/J they were 78 micrograms/kg and 74 micrograms/kg, respectively. In addition, a direct correlation between susceptibility to C. d. terrificus venom and creatine kinase serum levels (CK) was observed.