Adolfo R de Roodt

Publications of Adolfo R de Roodt

• Neutralization of Vipera and Macrovipera venoms by two experimental polyvalent antisera: a study of paraspecificity.

  Authors: Irving G Archundia, Adolfo R de Roodt, Blanca Ramos-Cerrillo, Jean-Philippe Chippaux, Laura Olguín-Pérez, Alejandro Alagón, Roberto P Stock

  Toxicon : official journal of the International Society on Toxinology. 06/2011; 57(7-8):1049-56.

  We conducted an extensive study of neutralization of lethality of 11 species and one subspecies of snakes of the genus Vipera, and of five species of Macrovipera, by two experimental equine antisera.We conducted an extensive study of neutralization of lethality of 11 species and one subspecies of snakes of the genus Vipera, and of five species of Macrovipera, by two experimental equine antisera. One antiserum was a trivalent preparation raised against the venoms of Vipera aspis aspis, Vipera berus berus and Vipera ammodytes ammodytes; the other was a pentavalent preparation that also included venoms of Vipera (now Montivipera) xanthina and Macrovipera lebetina obtusa. We measured specific neutralization of lethality against all venoms included in the immunization schemes, and paraspecific neutralization against the venoms of Vipera ammodytes montandoni, Vipera (Montivipera) bornmuelleri, Vipera latastei, Vipera (Mo.) latifii, Vipera (Mo.) lotievi, Vipera (Daboia) palaestinae, Vipera (Mo.) raddei and Vipera seoanei, as well as against Macrovipera (D.) deserti, Macrovipera lebetina cernovi, Macrovipera lebetina turanica and Macrovipera schweitzeri. We found an important degree of paraspecific protection within each genera (omitting recent reclassification) that was quite independent of both the lethal potency of the venoms and their geographic origin. This information may be of use to clinicians charged with the treatment of Vipera or Macrovipera envenomations with non-specific antivenoms.

• A study on the venom of Bothrops alternatus Duméril, Bibron and Duméril, from different regions of Argentina.

  Authors: Laura C Lanari, Sergio Rosset, María E González, Natalia Liria, Adolfo R de Roodt

  Toxicon : official journal of the International Society on Toxinology. 02/2010; 55(8):1415-24.

  We report a comparison of toxic and enzymatic activities of Bothrops alternatus venoms collected from specimens of different regions of Argentina with a pool of these same venoms. We determinedWe report a comparison of toxic and enzymatic activities of Bothrops alternatus venoms collected from specimens of different regions of Argentina with a pool of these same venoms. We determined lethal, hemorrhagic and pro-coagulant (plasma and fibrinogen) doses, as well as indirect hemolysis, hydrolysis of gelatin and fibrinogen. The electrophoretic pattern of the venoms and that of fibrinogen incubated with each of the venoms was studied by SDS-PAGE. The toxic activities were consistent with those reported for these venoms but with noticeable differences between samples which do not seem related to geographical or climatic characteristics. In some cases the pooled venom showed values close to the individual samples, but it was not representative since at least the half of the venoms (4/9) exhibited very different patterns of toxicity. The potency of some activities in the individual venoms ranged from much higher to much lower than those determined in the pooled venom (0.1 to 3 fold). Not all venoms exhibited thrombin-like activity but all hydrolyzed alpha and beta chains of fibrinogen; however, degradation patterns were not always similar. Variation in activities and toxicities do not seem to be related to geographical or climatic characteristics.

• General, biochemical and immunological characterization of the venom from the scorpion tityus trivittatus of argentina.

  Authors: Adolfo R de Roodt, Fredy I V Coronas, Nestor Lago, María E Gonzalez, Rodrigo D Laskowicz, Juan C Beltramino, Silvina Saavedra, Raúl A López, Gustavo Reati, Miriam G Vucharchuk, Eduardo Bazán, Liliana Varni, Oscar D Salomon, Lourival D Possani

  Toxicon : official journal of the International Society on Toxinology. 09/2009;

  Tityus trivittatus is the Argentinean scorpion reported to cause the majority of human fatalities in the country, however no systematic studies have been conducted with the venom of this species.Tityus trivittatus is the Argentinean scorpion reported to cause the majority of human fatalities in the country, however no systematic studies have been conducted with the venom of this species. This communication describes a general biochemical and immunological characterization of the venom obtained from T. trivittatus scorpions collected in the city of Buenos Aires and various provinces of Argentina: Catamarca, Cordoba, Entre Rios, La Rioja, Santa Fe and Santiago del Estero. These are places where human accidents were reported to occur due to this scorpion. For comparative purposes two types of samples were assayed: whole soluble venom obtained by electrical stimulation and supernatant from homogenized venomous glands. Two strains of mice (NIH and CF-1) were used for LD(50) determinations by two distinct routes of administration (intravenously and intraperitoneally). Important variations were found that goes from 0.5 to 12mg/Kg mouse body weight. Samples of soluble venom were always more potent than telson homogenates. More complex venom was observed in homogenates compared to soluble venom, as expected. This was supported by gel electrophoretic analysis and high performance liquid chromatographic separations (HPLC). Additionally, the HPLC profile was enriched in proteins resolved at similar elution times as other known toxins from scorpion venoms studied. Immune enzymatic assays were also conducted comparatively, using four different anti-venoms commercially available for treatment of scorpion stings (Argentinean antidote from INPB, two antivenoms from Butantan Institute of Brazil and Alacramyn from the Mexican Bioclon Institute). Cross-reactivities were observed and are reported among the various venoms and antivenoms used. Lung, heart and pancreas pathological modifications were observed on tissues of intoxicated mice. It seems that there are important variations on the venom compositions of the various samples studied and reported here, depending on the geographical area where the scorpions were captured. The results reported here are important for the clinical outcome of human accidents.

• Paraspecific neutralization of the venom of African species of cobra by an equine antiserum against Naja melanoleuca: a comparative study.

  Authors: Andrea Casasola, Blanca Ramos-Cerrillo, Adolfo R de Roodt, Alejandro Carbajal Saucedo, Jean-Philippe Chippaux, Alejandro Alagón, Roberto P Stock

  Toxicon : official journal of the International Society on Toxinology. 06/2009; 53(6):602-8.

  Venoms of snakes belonging to the same Genera tend to share biochemical, toxinological and antigenic characteristics. Accordingly, paraspecific neutralization of venom lethality by experimentalVenoms of snakes belonging to the same Genera tend to share biochemical, toxinological and antigenic characteristics. Accordingly, paraspecific neutralization of venom lethality by experimental antisera and commercial antivenoms has been reported. We studied the spectrum of neutralization of lethality of an experimental monovalent equine antiserum against the strongly neurotoxic African forest cobra (Naja melanoleuca) when tested against venoms of most species of African Naja, both neuro and cytotoxic as described by some authors. We report a comparison of the median lethal doses (LD50) of the venoms and the paraspecific median effective doses (ED50) of the antiserum calculated using three methods: Spearman-Kärber and Probit (currently recommended by the World Health Organization), and non-linear regression. An ample--but not complete--spectrum of paraspecific neutralization of lethality was observed against both spitting and non-spitting species of African Naja with a clearly more efficient neutralization of the more potent venoms, the implications of which are discussed. The median lethal and effective doses calculated by the three methods are remarkably consistent and may warrant consideration of non-linear regression methods for the calculation of venom lethality and antivenom potency by venom/antivenom researchers and producers.

• A new venomous scorpion responsible for severe envenomation in Argentina: Tityus confluens.

  Authors: Adolfo R de Roodt, Néstor R Lago, Oscar D Salomón, Rodrigo D Laskowicz, Lilia E Neder de Román, Raúl A López, Teresa E Montero, Valeria Del V Vega

  Toxicon : official journal of the International Society on Toxinology. 11/2008;

  In Argentina the scorpions of medical importance belong to the genus Tityus (T.), particularly the species T. trivittatus, the only scorpion whose sting is recognized to be associated with severeIn Argentina the scorpions of medical importance belong to the genus Tityus (T.), particularly the species T. trivittatus, the only scorpion whose sting is recognized to be associated with severe human envenoming and death. This genus is distributed from the north of the Patagonian region to the center and some provinces in the north of the country. During the period 2003-2006 four children died following scorpion stings, of which one was certainly and three were probably by T. confluens. In 2006, in the province of Tucumán, a girl died by scorpion envenoming and the scorpion responsible for the death, found in her shoe, was T. confluens. We thus studied the toxicity of venom gland homogenates from T. confluens from the provinces of Jujuy and Catamarca, and of crude venom from specimens from Catamarca and the province of La Rioja. The lethal potencies of the telson homogenates were 7.0 and 18.6mug/g for Jujuy and Catamarca, respectively, while the lethal potency of the crude venom was 0.7mug/g. Injected mice showed generalized congestion and hepatic lesions. Pancreatic damage was observed in some animals. Lungs showed congestion and foci of hemorrhage and mild edema. The heart showed injury in the muscular fibers. The venom showed high reactivity against anti-T. trivittatus antivenom and against two anti-T. serrulatus antivenoms. The anti-T. trivittatus antivenom neutralized the lethal activity of T. confluens venom. In addition, the venom reacted very slightly against an anti-Centruroides antivenom. Therefore, the stings of this scorpion must be considered of risk for humans to the same degree as the stings of T. trivittatus.

• Characterization of a new polyvalent antivenom (Antivipmyn((R)) Africa) against African vipers and elapids.

  Authors: Blanca Ramos-Cerrillo, Adolfo R de Roodt, Jean-Philippe Chippaux, Laura Olguín, Andrea Casasola, Guadalupe Guzmán, Jorge Paniagua-Solís, Alejandro Alagón, Roberto P Stock

  Toxicon : official journal of the International Society on Toxinology. 10/2008;

  As a response to the antivenom shortage in Sub-Saharan Africa, evident for well over a decade, we developed a new polyvalent anti-ophidian antivenom (Antivipmyn((R)) Africa) designed for use in theAs a response to the antivenom shortage in Sub-Saharan Africa, evident for well over a decade, we developed a new polyvalent anti-ophidian antivenom (Antivipmyn((R)) Africa) designed for use in the region. We report a detailed characterization of its biochemical composition (protein content and profiling by size-exclusion chromatography and electrophoresis) as well as the specific and para-specific neutralization potencies (as median effective dose in the mouse lethality test). Additionally, we studied the neutralization of hemorrhagic, anti-hemostatic and necrotic activities of Echis ocellatus venom, responsible for a majority of severe envenomations in the continent according to existing epidemiological data. The antivenom is currently under production and has already been employed in the field in a pragmatic Phase III clinical trial in the Republic of Benin. It is a purified lyophilized polyvalent equine F(ab')(2)-based product obtained by immunization with the venoms of eleven species of African snakes of the Genera Echis, Bitis, Naja and Dendroaspis. The criteria for its design are discussed, particularly in terms of the implementation of realistic public health policies targeting mostly rural populations in the continent.

• A novel toxin from the venom of the scorpion Tityus trivittatus, is the first member of a new alpha-KTX subfamily.

  Authors: Yousra Abdel-Mottaleb, Fredy V Coronas, Adolfo R de Roodt, Lourival D Possani, Jan Tytgat

  FEBS letters. 02/2006; 580(2):592-6.

  The first example of a new sub-family of toxins (alpha-KTx20.1) from the scorpion Tityus trivittatus was purified, sequenced and characterized physiologically. It has 29 amino acid residues, threeThe first example of a new sub-family of toxins (alpha-KTx20.1) from the scorpion Tityus trivittatus was purified, sequenced and characterized physiologically. It has 29 amino acid residues, three disulfide bridges assumed to adopt the cysteine-stabilized alpha/beta scaffold with a pI value of 8.98. The sequence identities with all the other known alpha-KTx are less than 40%. Its effects were verified using seven different cloned K(+) channels (vertebrate Kv1.1-1.5, Shaker IR and hERG) expressed in Xenopus leavis oocytes. The toxin-induced effects show large differences among the different K(+) channels and a preference towards Kv1.3 (EC50=7.9+/-1.4 nM).

• Recombinant GRA4 or ROP2 protein combined with alum or the gra4 gene provides partial protection in chronic murine models of toxoplasmosis.

  Authors: Valentina Martin, Alicia Supanitsky, Pablo C Echeverria, Silvana Litwin, Tamara Tanos, Adolfo R de Roodt, Eduardo A Guarnera, Sergio O Angel

  Clinical and diagnostic laboratory immunology. 08/2004; 11(4):704-10.

  The efficacy of vaccination with Toxoplasma gondii recombinant GRA4 (rGRA4) and ROP2 (rRPO2) proteins and a mix of both combined with alum were evaluated in C57BL/6 and C3H mice. In C57BL/6 mice,The efficacy of vaccination with Toxoplasma gondii recombinant GRA4 (rGRA4) and ROP2 (rRPO2) proteins and a mix of both combined with alum were evaluated in C57BL/6 and C3H mice. In C57BL/6 mice, rGRA4 and rGRA4-rROP2 immunizations generated similar levels of immunoglobulin G1 (IgG1) and IgG2a isotypes against GRA4, whereas immunizations with rROP2 and the mix induced a predominant IgG1 production against ROP2. All groups of C3H vaccinated mice exhibited higher levels of IgG1 than IgG2a. rGRA4-stimulated splenocytes from vaccinated mice produced primarily gamma interferon while those stimulated with rROP2 produced interleukin-4. Challenge of rGRA4- or rGRA4-rROP2-vaccinated mice from both strains with ME49 cysts resulted in fewer brain cysts than the controls, whereas vaccination with rROP2 alone only conferred protection to C3H mice. Immunization with a plasmid carrying the entire open reading frame of GRA4 showed a protective level similar to that of rGRA4 combined with alum. These results suggest that GRA4 can be a good candidate for a multiantigen anti-T. gondii vaccine based on the use of alum as an adjuvant.

• Effectiveness of two common antivenoms for North, Central, and South American Micrurus envenomations.

  Authors: Adolfo R de Roodt, Jorge F Paniagua-Solis, Jorge A Dolab, Judith Estévez-Ramiréz, Blanca Ramos-Cerrillo, Silvana Litwin, José C Dokmetjian, Alejandro Alagón

  Journal of toxicology. Clinical toxicology. 02/2004; 42(2):171-8.

  Micrurus snakes (coral snakes) may produce severe envenomation that can lead to death by peripheral respiratory paralysis. Only few laboratories produce specific antivenoms, and despite theMicrurus snakes (coral snakes) may produce severe envenomation that can lead to death by peripheral respiratory paralysis. Only few laboratories produce specific antivenoms, and despite the cross-reactivity found in some Micrurus species venoms, the treatment is not always effective. To test two therapeutic antivenoms against the venom of four species of Micrurus from Southern America, North of South America, Central America, and North America, the determination of the lethal potency of the venoms, the study of some biochemical and immunochemical characteristics, and the determination of the neutralizing activity of both antivenoms were studied. North American and South American antivenoms neutralized well venoms from Micrurus species of the corresponding hemisphere but displayed lower effectiveness against venoms of species from different hemispheres. It was concluded that the neutralization of Micrurus venoms by regional antivenoms could be useful to treat the envenomation by some Micrurus snakes but is necessary to evaluate carefully the antivenoms to be used with the venoms from the snakes of the region. Also, considering the difficulties for coral snake antivenom production, the development of a polyvalent antivenom is useful to treat the envenomation by coral snakes from different regions is necessary.

• Epidemiological and clinical aspects of scorpionism by Tityus trivittatus in Argentina.

  Authors: Adolfo R de Roodt, Susana I García, Oscar D Salomón, Liliana Segre, Jorge A Dolab, Raúl F Funes, Ernesto H de Titto

  Toxicon : official journal of the International Society on Toxinology. 07/2003; 41(8):971-7.

  This is a descriptive study of epidemiological and clinical aspects of stings caused by the scorpion Tityus trivittatus in Argentina. We analyzed 511 cases recorded from different health centers inThis is a descriptive study of epidemiological and clinical aspects of stings caused by the scorpion Tityus trivittatus in Argentina. We analyzed 511 cases recorded from different health centers in 22 provinces. Most accidents took place during the period November-April (76%), in or nearby houses (86%). Over 50% of the accidents involved children and teenagers. Envenomation by T. trivittatus was mainly characterized by local symptoms: pain (85%), edema (26.6%), burning sensation (24.7%), erythema (20.7%), local hyperthermia (13.1%), paresthesia (9.8%) and general manifestations such as vomiting (25%), paleness (18.8%), headache (11.4%) and sweating (8.2%). Neurological, cardiovascular and respiratory disorders were uncommon. Almost 90% of the injured people got treated with specific antivenom within 2 h, 6% were treated 2-h after the accident and only 2 people were treated 12 or more hours after being stung. The global mortality recorded was 6 per 1000 cases. Scorpionism in Argentina is a public health problem under control due to the relatively low incidence and the accessibility of specific antivenom.

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• Disulfide bridges and blockage of Shaker B K(+)-channels by another butantoxin peptide purified from the Argentinean scorpion Tityus trivittatus.

  Authors: Fredy V Coronas, Adolfo R de Roodt, Timoteo Olamendi-Portugal, Fernando Z Zamudio, Cesar V F Batista, Froylan Gómez-Lagunas, Lourival D Possani

  Toxicon : official journal of the International Society on Toxinology. 03/2003; 41(2):173-9.

  A peptide was isolated from the venom of the scorpion Tityus trivittatus. It is an isoform of the toxin TsTX-IV earlier described [Toxicon 37 (1999) 651] and identical to butantoxin [Arch. Biochem.A peptide was isolated from the venom of the scorpion Tityus trivittatus. It is an isoform of the toxin TsTX-IV earlier described [Toxicon 37 (1999) 651] and identical to butantoxin [Arch. Biochem. Biophys. 379 (2000) 18], both isolated from the Brazilian scorpion Tityus serrulatus. This newly characterized peptide contains 40 amino acid residues with a molecular mass of [M+H(+)] 4507.0, cross-linked by four disulfide bridges, made between the cysteine pairs: Cys2-Cys5, Cys10-Cys31, Cys16-Cys36 and Cys20-Cys38. It blocks in a completely reversible manner the Shaker B K(+)-channels, with a K(d) around 660nM. It belongs to the sub-family 12 and it is now being classified as alpha-KTx 12.2.

• [Poisoning by spiders of Loxosceles genus]

  Authors: Adolfo R de Roodt, Oscar D Salomón, Susana C Lloveras, Tomás A Orduna

  Medicina. 02/2002; 62(1):83-94.

  Despite the great number of spiders in the world, only a small group of them is capable of producing death in humans. In Argentina, there are only three of the four genera of spiders considered ofDespite the great number of spiders in the world, only a small group of them is capable of producing death in humans. In Argentina, there are only three of the four genera of spiders considered of high risk to humans: Latrodectus is present in rural areas, Phoneutria is restricted to small regions while Loxosceles is distributed throughout the country. Accidents by Loxosceles represent around 4% of the total number produced by venomous animals in Argentina. The bite is accidental and may produce considerable local necrosis with scar formation and ulcers of slow and difficult healing that may require surgical repair. Some bitten people may suffer from intravascular hemolysis, disseminated coagulation and acute renal insufficiency leading to death. Despite the great number of studies performed on Loxosceles venoms, at present, the physiopathological course of poisoning is not clear and there is not common criteria for its treatment. In this review, biological and epidemiological data of this spider are described as well as the venom composition and the possible participation of its components in the poisoning. These data provide biological and biochemical tools to understand the course of poisoning and to have better criteria for the treatment and prevention of these accidents and their complications.

• Cross-reactivity and heterologous neutralization of crotaline antivenoms used in Argentina

  Authors: Adolfo R. de Roodt, Jorge A. Dolab, Teresa Fernández, Liliana Segre, Silvia E. Hajos

  Toxicon.

  The immunochemical cross-reactivity and neutralizing capacity of four crotalinae antivenoms consisting in equine F(ab′)2 fragments and available in Argentina (bothropic Bivalent, against BothropsThe immunochemical cross-reactivity and neutralizing capacity of four crotalinae antivenoms consisting in equine F(ab′)2 fragments and available in Argentina (bothropic Bivalent, against Bothrops alternatus and B. neuwiedii venoms; bothropic Tetravalent, against B. alternatus, B. neuwiedii; B. jararaca and B. jararacussu venoms; bothropic–crotalic Trivalent, against B. alternatus, B. neuwiedii and Crotalus (C.) durissus terrificus venoms and anticrotalic against C. d. terrificus venom) were studied against B. alternatus, B. ammodytoides; B. jararaca; B. jararacussu; B. moojeni; B. neuwiedii and C. d. terrificus venoms. SDS-PAGE analysis of the Bothrops venoms showed protein bands of high (>40 kDa) medium (20–40 kDa) and low (<15 kDa) molecular weights, while that of C. d. terrificus exhibited a large amount of material with molecular weight of 15.0 kDa or lower. Immunoblotting showed a high cross-reactivity of all the major protein bands with all the antivenoms (even heterologous) tested. All the antivenoms were effective in neutralizing the lethal activity of the venoms tested, and in some cases (B. jararaca and B. jararacussu) heterologous antivenoms exhibited similar neutralizing capacity than the homologous ones. In spite of the differences in biochemical composition and pharmacology, Bothropic antivenoms displayed a significant neutralizing capacity on lethal activity of C. d. terrificus venom. In addition, all the antivenoms (including the anticrotalic) were highly effective in neutralizing the hemorragic, necrotizing, procoagulant, and proteolytic activities. The antivenoms tested produced different degrees of inhibition of phospholipase A2 activity, which exhibited a certain specificity but was also related to the enzyme content in the venom.

• [Poisoning by bee sting]

  Authors: Adolfo R de Roodt, Oscar D Salomón, Tomás A Orduna, Luis E Robles Ortiz, Jorge F Paniagua Solís, Alejandro Alagón Cano

  Gaceta médica de México. 141(3):215-22.

  Among the human pathologies produced by venomous animals, bee stings constitute the largest number of accidents in several countries, exceeding the mortality rate caused by other venomous animalsAmong the human pathologies produced by venomous animals, bee stings constitute the largest number of accidents in several countries, exceeding the mortality rate caused by other venomous animals such as snakes, spiders or scorpions. The clinical picture after the bee sting may include anaphylaxis or poisoning. The latter is produced by massive attacks and is a serious problem that may put the patient's life at risk. People that are poisoned display hemolysis, rhabdomiolysis and acute renal failure that together with other systemic failures can bring about death. The knowledge of the physiopathological mechanisms involved in the massive attack of bees is crucial for health care professionals as to date we do not have antivenoms with proven clinical efficacy. In this review we include the bee's biological aspects, venom composition and its relation with the occurrence and severity of accidents as well as epidemiological data that can be useful for this type of accidents.

• General biochemical and immunological characterization of the venom from the scorpion Tityus trivittatus of Argentina

  Authors: Adolfo R. de Roodt, Fredy I.V. Coronas, Nestor Lago, María E. González, Rodrigo D. Laskowicz, Juan C. Beltramino, Silvina Saavedra, Raúl A. López, Gustavo J. Reati, Miriam G. Vucharchuk, Eduardo Bazán, Liliana Varni, Oscar D. Salomón, Lourival D. Possani

  Toxicon.

  Tityus trivittatus is the Argentinean scorpion reported to cause the majority of human fatalities in the country, however no systematic studies have been conducted with the venom of this species.Tityus trivittatus is the Argentinean scorpion reported to cause the majority of human fatalities in the country, however no systematic studies have been conducted with the venom of this species. This communication describes a general biochemical and immunological characterization of the venom obtained from T. trivittatus scorpions collected in the city of Buenos Aires and various provinces of Argentina: Catamarca, Cordoba, Entre Rios, La Rioja, Santa Fe and Santiago del Estero. These are places where human accidents were reported to occur due to this scorpion. For comparative purposes two types of samples were assayed: whole soluble venom obtained by electrical stimulation and supernatant from homogenized venomous glands. Two strains of mice (NIH and CF-1) were used for LD50 determinations by two distinct routes of administration (intravenously and intraperitoneally). Important variations were found that goes from 0.5 to 12 mg/kg mouse body weight. Samples of soluble venom were always more potent than Telson homogenates. More complex pattern was observed in homogenates compared to soluble venom, as expected. This was supported by gel electrophoretic analysis and high performance liquid chromatographic (HPLC) separations. Additionally, the HPLC profile was enriched in proteins resolved at similar elution times as other known toxins from scorpion venoms studied. Immune enzymatic assays were also conducted comparatively, using four different anti-venoms commercially available for treatment of scorpion stings (Argentinean antidote from INPB, two anti-venoms from Butantan Institute of Brazil and Alacramyn from the Mexican Bioclon Institute). Cross-reactivities were observed and are reported among the various venoms and anti-venoms used. Lung, heart, liver and pancreas pathological modifications were observed on tissues of intoxicated mice. It seems that there are important variations on the venom compositions of the various samples studied and reported here, depending on the geographical area where the scorpions were captured. The results reported here are important for the clinical outcome of human accidents.

• [Toxicity of venoms from snakes of medical importance in México]

  Authors: Adolfo R de Roodt, Judith Estévez-Ramírez, Jorge F Paniagua Solís, Silvana Litwin, Alejandro Carvajal-Saucedo, Jorge A Dolab, Luis E Robles Ortiz, Alejandro Alagón

  Gaceta médica de México. 141(1):13-21.

  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.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 nigrocinctus. The studies performed were: SDS-PAOE, determination of lethal potency, hemorrhagic, necrotizing, coagulation on plasma and fibrinogen, phospholipasic and fibri(noge)nolytic activities. In addition we studied the neutralizing capacity of the toxic activities of an antivenom currently used for the treatment of snakebites in Mexico. The venom from viperids showed important hemorrhagic, necrotizing, coagulative on plasma, prothrombinic, fibrinogenolytic and phospholipase activities. The venoms with the highest lethal potency were those of Micrurus nigrocinctus and Crotalus scutulatus; however, the viperine venom that globally displayed the most potent toxic activities was from Bothrops asper. All the venoms showed toxic activities of similar range to those described for other American venomous snakes. The activity on plasma or fibrinogen varied widely among the different venoms but all displayed capacity to act on the coagulation system. The antivenom tested not only neutralized the lethality B. asper venom but also its other toxic activities.