RESUMO
According to the World Health Organization, snakebites are considered neglected diseases. Bothrops, the genus most frequently implicated in envenomations in Brazil, includes the species B. marajoensis Hoge, 1966, part of the complex B. atrox, which is found in the savannas of Marajó Island, Pará state, Brazil, a region that presents scarce epidemiological data. This work reports the first case of hemorrhagic stroke in a child, attributed to delayed medical care after snakebite envenoming by Bothrops marajoensis in Anajás city, Marajó Island, Pará, Brazil, which led to permanent hemiplegia as a sequela.(AU)
Assuntos
Humanos , Animais , Criança , Mordeduras de Serpentes , Bothrops , Acidente Vascular Cerebral , Hemiplegia , Relatório de PesquisaRESUMO
According to the World Health Organization, snakebites are considered neglected diseases. Bothrops, the genus most frequently implicated in envenomations in Brazil, includes the species B. marajoensis Hoge, 1966, part of the complex B. atrox, which is found in the savannas of Marajó Island, Pará state, Brazil, a region that presents scarce epidemiological data. This work reports the first case of hemorrhagic stroke in a child, attributed to delayed medical care after snakebite envenoming by Bothrops marajoensis in Anajás city, Marajó Island, Pará, Brazil, which led to permanent hemiplegia as a sequela.
Assuntos
Humanos , Animais , Acidente Vascular Cerebral , Bothrops , Hemorragia , Mordeduras de Serpentes , Venenos de CrotalídeosRESUMO
Bmaj-9, a basic PLA2 (13679.33 Da), was isolated from Bothrops marajoensis snake venom through only one chromatographic step in reversed phase HPLC on »-Bondapak C-18 column. The amino acid composition showed that Bmaj-9 had a high content of Lys, His, and Arg, typical of a basic PLA2. The sequence of Bmaj-9 contains 124 amino acid residues with a pI value of 8.55, such as DLWQWGQMIL KETGKLPFSY YTAYGCYCGW GGRGGKPKAD TDRCCFVHDC, revealing a high homology with Asp49 PLA2 from other snake venoms. It also exhibited a pronounced phospholipase A2 activity when compared with crude venom. In chick biventer cervicis preparations, the time for 50 percent and 100 percent neuromuscular paralysis was respectively (in minutes): 110 ± 10 (1 µg/mL); 40 ± 6 and 90 ± 2 (5 µg/mL); 30 ± 3 and 70 ± 5 (10 µg/mL); 42 ± 1 and 60 ± 2 (20 µg/mL), with no effect on the contractures elicited by either exogenous ACh (110 µM) or KCl (20 mM). Bmaj-9 (10 µg/mL) neither interfered with the muscular response to direct electrical stimulation in curarized preparations nor significantly altered the release of CK at 0, 15, 30 and 60 minutes incubations (27.4 ± 5, 74.2 ± 8, 161.0 ± 21 and 353.0 ± 47, respectively). The histological analysis showed that, even causing blockade at the maximum dosage (5 µg/mL), the toxin does not induce significant morphological alterations such as necrosis or infiltration of inflammatory cells. These results identified Bmaj-9 as a new member of the basic Asp49 PLA2 family able to interact with the motor nerve terminal membrane, thereby inducing a presynaptic neuromuscular blockade.