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Neutralization of the neuromuscular activity of bothropstoxin-i, a myotoxin from Bothrops jararacussu snake venom, by a hydroalcoholic extract of Casearia sylvestris Sw. (gua?atonga)
Oshima-Franco, Y.;Alves, C. M. V.;Andréo Filho, N.;Gerenutti, M.;Cintra, A. C. O.;Leite, G. B.;Rodrigues-Simioni, L.;Silva, M. G.;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2005, DOI: 10.1590/S1678-91992005000400007
Abstract: numerous plants are used as snakebite antidotes in brazilian folk medicine, including casearia sylvestris swartz, popularly known as gua?atonga. in this study, we examined the action of a hydroalcoholic extract from c. sylvestris on the neuromuscular blockade caused by bothropstoxin-i (bthtx-i), a myotoxin from bothrops jararacussu venom, in mouse isolated phrenic nerve-diaphragm (pnd) preparations. aqueous (8 and 12 mg/ml, n=4 and 5, respectively) and hydroalcoholic (12 mg/ml, n=12) extracts of the leaves of c. sylvestris caused facilitation in pnd preparations followed by partial neuromuscular blockade. bthtx-i (20 μg/ml, n=4) caused 50% paralysis after 65±15 min (mean ± s.e.m). preincubation (30 min at 37° c) of bthtx-i (20 μg/ml, n=4) with a concentration of the hydroalcoholic extract (4 mg/ml) that had no neuromuscular activity, such as the control (n=5), prevented the neuromuscular blockade caused by the toxin. this protection may be mediated by compounds such as flavonoids and phenols identified by thin-layer chromatography and colorimetric assays.
Novelties in Casearia (Flacourtiaceae) for Argentina NOVEDADES EN CASEARIA (FLACOURTIACEAE) PARA ARGENTINA
Héctor A. Keller,Fabián E. Gatti,Justo Herrera
Bonplandia , 2010,
Abstract: Casearia obliqua Spreng. (Flacourtiaceae) is recorded for the first time to Argentina, based on specimens collected beside Iguazú river, in Misiones province. The taxon is here described and illustrated. The presence of Casearia gossypiosperma Briq. in Misiones, a tree mentioned in 1936 for that province, is here documented by mean herbarium material. A key for identifying the argentinean species is included Se cita por primera vez para la flora de Argentina, Casearia obliqua Spreng. (Flacourtiaceae), sobre la base de ejemplares recolectados junto al río Iguazú, en la provincia de Misiones. Este taxón es descripto e ilustrado. Se certifica mediante material de herbario la presencia en Misiones de Casearia gossypiosperma Briq., especie arbórea que fue mencionada para dicha provincia en 1936. Se incluye una clave para determinar las especies de Casearia de Argentina.
Novedades en Casearia (Flacourtiaceae) para Argentina
Héctor A. Keller,Fabian E. Gatti,Justo Herrera
Bonplandia , 2009,
Abstract: Casearia obliqua Spreng. (Flacourtiaceae) is recorded for the first time to Argentina, based on specimens collected beside Iguazú river, in Misiones province. The taxon is here described and illustrated. The presence of Casearia gossypiosperma Briq. in Misiones, a tree mentioned in 1936 for that province, is here documented by mean herbarium material. A key for identifying the argentinean species is included.
Acción del veneno de Bothrops jararacussu de Argentina sobre la coagulación sanguínea
Maru?ak,S.L.; Ruíz de Torrent,R.M.; Teibler,G.P.; Gay,C.C.; Leiva,L.; Acosta de Pérez,O.;
InVet , 2006,
Abstract: the envenomation by snakes of the genus bothrops of argentina causes local and systemic signs. among the systemic damages, bothropic venoms induce a wide variety of effects on blood coagulation, haemorrhage, shock and renal failure. in this paper the effects of bothrops jararacussu venom from argentina on the hemostatic system were determined. in order to estimate blood-clotting, fibrinolytic and defibrinating activities of the venom, in vitro and in vivo tests were employed. the ability to degrade fibrinogen and the lethal dosis (dl50) also were determined. the b. jararacussu venom appears to be fibrinogenolytic and the values obtained for assayed activities were minimum blood-clotting concentration 18,5 μg/ml, minimum fibrinolytic dose 9,5 mg/ml, minimum defibrinating dose 1,56 μg, ld50 43,52 μg/mouse. these results differ from those obtained for other species of genus bothrops, or from the same species that inhabits in different south american regions. it is concluded that bothrops jararacussu venom from argentina largely affects blood coagulation system, and that the procoagulant and anticoagulant activities exhibited by this secretion may contribute to the lethality of the venom, since they could promote hemorrhages which could lead to renal failure and death of the victim in severe envenomation.
A eficácia do antiveneno botrópico-crotálico na neutraliza??o das principais atividades do veneno de Bothrops jararacussu
dos-Santos, Maria Cristina;Gon?alves, Luís Roberto de Camargo;Fortes-Dias, Consuelo L.;Cury, Yara;Gutiérrez, José Maria;Furtado, Maria de Fátima D.;
Revista do Instituto de Medicina Tropical de S?o Paulo , 1992, DOI: 10.1590/S0036-46651992000200001
Abstract: myonecrosis is one of the effects of bothrops jararacussu venom, from which a myotoxin was isolated showing structural homology to phospholipase a2 (pla2), but without enzimatic activity. such myotoxic activity is also present in the crotalus durissus terrificus venom, and is atributed to crotoxin and to pla2 (crotoxin b), the basic component of the crotoxin complex. the bothrops jararacussu venom showed three proteins with immunologic identity to pla2 from crotoxin. the bothropic (ab) and the bothropic/crotalic (ab/c) antivenoms, two commercial polyvalent antivenoms produced at instituto butantan, were compared in order to assess their capacity for neutralization of the lethal, hemorrhagic, coagulant and myotoxic activities of bothrops jararacussu venom. both antivenoms showed the same level of hemorrhagic activity neutralization. however, ab/c was about three times more efficient than ab in neutralizing the myotoxic activity, and two times more potent for neutralization of lethality and coagulant activity of bothrops jararacussu venom. these data suggest that the use of ab/c could be of value in the treatment of patients bitten by snakes of this species
Circadian rhythm of locomotor activity in Bothrops jararacussu (Serpentes: Viperidae)
José Geraldo Pereira da Cruz
Biotemas , 2007,
Abstract: Many biochemical, physiological, and behavioral parameters exhibited by organisms show daily fluctuations, and most of these fluctuations persist when the organisms are maintained in constant environmental conditions, thus demonstrating that they are driven by an endogenous oscillator. Locomotor activity in reptiles is restricted temporally by the circadian system. The relative stability of the patterns and the amount of locomotor activity per cycle suggest that this behavior may be regulated by some conservative mechanism. In the present study, the behavior of Bothrops jararacussu was analyzed under animals housed in 24h light/dark cycle and dark/light cycle, to determine which aspects of this behavior were conserved. The Bothrops jararacussu displayed a nocturnal activity preference with monophasic activity patterns during the light/dark cycles, and this shows a free-running rhythm. The rhythm of locomotor activity disappears in the 24h dark/light cycle. Many parameters exhibited by organisms show daily fluctuations that may persist when the organisms are held in constant environmental conditions.
Acción del veneno de Bothrops jararacussu de Argentina sobre la coagulación sanguínea Activity of the venom of Bothrops jararacussu of Argentina on blood coagulation  [cached]
S.L. Maru?ak,R.M. Ruíz de Torrent,G.P. Teibler,C.C. Gay
InVet , 2006,
Abstract: La intoxicación por mordeduras de serpientes del género Bothrops (yarará) de Argentina se caracteriza por causar efectos locales y sistémicos. Entre los sistémicos pueden generar alteraciones en la coagulación de la sangre, hemorragias, shock, insuficiencia renal. En este trabajo se estudiaron los efectos que causa el veneno de Bothrops jararacussu de Misiones, Argentina, sobre la coagulación de la sangre. Se utilizaron métodos in vitro e in vivo para evaluar la actividad coagulante, fibrinolítica y defibrinante, como así también la capacidad de degradar el fibrinógeno y la letalidad del veneno. El veneno mostró ser α-fibrinogenolítico y los resultados para las actividades ensayadas fueron: concentración coagulante mínima (CCM) 18,5 μg/ml, concentración fibrinolítica mínima (CFM) 9,5 mg/ml, dosis defibrinante mínima (DDM) 1,56 μg, DL50 43,52 μg/ratón, los que difieren de los obtenidos para otras especies de Bothrops e incluso dentro de la misma especie, pero distribuídas en otras regiones sudamericanas. Se concluye que el veneno de B. jararacussu de Argentina afecta marcadamente el sistema hemostático, y que las actividades coagulantes y anticoagulantes exhibidas por esta secreción probablemente influyan en la letalidad del veneno, dado que contribuirían a la aparición de hemorragias que, de ser severas, conducen a fallo renal y muerte de la víctima. The envenomation by snakes of the genus Bothrops of Argentina causes local and systemic signs. Among the systemic damages, bothropic venoms induce a wide variety of effects on blood coagulation, haemorrhage, shock and renal failure. In this paper the effects of Bothrops jararacussu venom from Argentina on the hemostatic system were determined. In order to estimate blood-clotting, fibrinolytic and defibrinating activities of the venom, in vitro and in vivo tests were employed. The ability to degrade fibrinogen and the lethal dosis (DL50) also were determined. The B. jararacussu venom appears to be fibrinogenolytic and the values obtained for assayed activities were minimum blood-clotting concentration 18,5 μg/ml, minimum fibrinolytic dose 9,5 mg/ml, minimum defibrinating dose 1,56 μg, LD50 43,52 μg/mouse. These results differ from those obtained for other species of genus Bothrops, or from the same species that inhabits in different South American regions. It is concluded that Bothrops jararacussu venom from Argentina largely affects blood coagulation system, and that the procoagulant and anticoagulant activities exhibited by this secretion may contribute to the lethality of the venom, since they could promo
Anti-inflammatory activity of Blutaparon portulacoides ethanolic extract against the inflammatory reaction induced by Bothrops jararacussu venom and isolated myotoxins BthTX-I and II
Pereira, IC;Barbosa, AM;Salvador, MJ;Soares, AM;Ribeiro, W;Cogo, JC;Zamuner, SR;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2009, DOI: 10.1590/S1678-91992009000300013
Abstract: this article reports the anti-inflammatory effect of blutaparon portulacoides (b. portulacoides), specifically the ethanolic extract of its aerial parts, on the edema formation and leukocyte influx caused by bothrops jararacussu (b. jararacussu) snake venom and bothropstoxin-i and ii (bthtx-i and ii) isolated from this venom as an alternative treatment for bothrops snakebites. the anti-inflammatory effect of b. portulacoides ethanolic extract was compared with an animal group pretreated with dexamethasone. b. portulacoides ethanolic extract significantly inhibited paw edema induced by b. jararacussu venom and by bthtx-i and ii. also, results demonstrated that the extract caused a reduction of the leukocyte influx induced by bthtx-i. however, the extract was not capable of inhibiting the leukocyte influx induced by the venom and by bthtx-ii. in conclusion, these results suggest that the ethanolic extract of this plant possess components able to inhibit or inactivate toxins present in b. jararacussu venom, including its myotoxins, responsible for the edema formation. however, the leukocyte migration caused by the venom and bthtx-ii was not inhibited by the plant, probably due to the different mechanisms involved in the edema formation and leukocyte influx. this is the first report of b. portulacoides extract as anti-inflammatory against snake venoms and isolated toxins.
Daily patterns of the locomotor activity of Bothrops jararacussu (Serpentes: Viperidae): A response to environmental lighting conditions or an endogenous rhythm?
José Geraldo Pereira da Cruz,Débora Delwing Del Magro,Júlia Niehues da Cruz
Biotemas , 2008,
Abstract: While most circadian biologists would probably assume that circadian clocks drive activity patterns, it is also well known that environmental stimuli may mask endogenous rhythms by either increasing or suppressing activity. The hypothesis that circadian rhythms are generally entrained by exogenous cycles was experimentally tested in Bothrops jararacussu. In this study, we investigated the locomotor activity under constant light and constant dark conditions for 24 days and compared it to that of control snakes living under a light/dark cycle. Under the light/dark cycle, one peak of activity was observed during the night phase, which is typical of the circadian rhythms of nocturnal species. Constant light on Bothrops jararacussu promoted a significant fragmentation and an overall increase in the amount of locomotor activity, while constant darkness provoked a significant suppression of activity. This circadian rhythm is probably endogenous, primarily synchronized by alternating light and darkness. Constant light induces desynchronization, and constant darkness leads to the blockage of circadian clocks. The functional significance of these circadian changes suggests a small flexibility in circadian organization in response to environmental conditions.
Rabbit antivenom efficacy against myotoxic and neurotoxic activities of Bothrops jararacussu venom and bothropstoxin-I
Oshima-Franco, Y.;Leite, G. B.;Valério, A. A.;Hyslop, S.;Andriao-Escarso, S.;Giglio, J. R.;Prado-Franceschi, J.;Cruz-H?fling, M. A.;Rodrigues-Simioni, L.;
Journal of Venomous Animals and Toxins , 2002, DOI: 10.1590/S0104-79302002000200004
Abstract: bothrops jararacussu venom and its major toxin bothropstoxin-i (bthtx-i) possess myotoxic and neurotoxic properties. the efficacy of a rabbit antivenom raised against b. jararacussu venom in the neutralization of physiological, biochemical, and morphological changes induced by the venom and its major toxin bthtx-i was studied in mouse isolated phrenic nerve-diaphragm (pnd) and extensor digitorum longus (edl) preparations. the times required for 50% neuromuscular blockade in pnd and edl preparations for venom were 70+11.5 (s.e.m., n=5) min and 58+8 (n=16) (50 m g/ml), and for bthtx-i 31+6 (n=3) min and 30+3 (n=5) min (20 m g/ml), respectively. after 120 min incubation, creatine kinase (ck) concentrations in solution containing the edl preparations were 3464+346 u/l after exposure to venom (50 m g/ml, n=5) and 3422+135 u/l to bthtx-i (20m g/ml, n=4), respectively. rabbit antivenom dose-dependently neutralized venom and toxin-induced neuromuscular blockade in both preparations and effectively prevented venom and toxin-induced ck release from edl. histological analysis showed that rabbit antivenom neutralized morphological damage caused by b. jararacussu venom and bthtx-i in edl preparations. these results indicate that rabbit antivenom effectively neutralized the biological activities of b. jararacussu venom and bthtx-i.
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