ABSTRACT
Recently, a designed class of efficient analgesic drugs derived from an endogenous neuropeptide, kyotorphin (KTP, Tyr-Arg) combining C-terminal amidation (KTP-NH2) and N-terminal conjugation to ibuprofen (Ib), IbKTP-NH2, was developed. The Ib moiety is an enhancer of KTP-NH2 analgesic action. In the present study, we have tested the hypothesis that KTP-NH2 is an enhancer of the Ib anti-inflammatory action. Moreover, the impact of the IbKTP-NH2 conjugation on microcirculation was also evaluated by a unified approach based on intravital microscopy in the murine cremasteric muscle. Our data show that KTP-NH2 and conjugates do not cause damage on microcirculatory environment and efficiently decrease the number of leukocyte rolling induced by lipopolysaccharide (LPS). Isothermal titration calorimetry showed that the drugs bind to LPS directly thus contributing to LPS aggregation and subsequent elimination. In a parallel study, molecular dynamics simulations and NMR data showed that the IbKTP-NH2 tandem adopts a preferential "stretched" conformation in lipid bilayers and micelles, with the simulations indicating that the Ib moiety is anchored in the hydrophobic core, which explains the improved partition of IbKTP-NH2 to membranes and the permeability of lipid bilayers to this conjugate relative to KTP-NH2. The ability to bind glycolipids concomitant to the anchoring in the lipid membranes through the Ib residue explains the analgesic potency of IbKTP-NH2 given the enriched glycocalyx of the blood-brain barrier cells. Accumulation of IbKTP-NH2 in the membrane favors both direct permeation and local interaction with putative receptors as the location of the KTP-NH2 residue of IbKTP-NH2 and free KTP-NH2 in lipid membranes is the same.
Subject(s)
Analgesics/chemistry , Anti-Inflammatory Agents/chemistry , Endorphins/metabolism , Lipid Bilayers/metabolism , Analgesics/metabolism , Animals , Anti-Inflammatory Agents/metabolism , Endorphins/chemistry , Female , Lipid Bilayers/chemistry , Lipopolysaccharides/chemistry , Lipopolysaccharides/metabolism , Male , Mice , Molecular Dynamics Simulation , Molecular StructureABSTRACT
Toxic cyanobacteria in public water reservoirs may cause severe health issues for livestock and human beings. Geitlerinema amphibium, which is frequently found in São Paulo Citys drinking water supplies, showed toxicity in the standard mouse bioassay, while displaying signs of intoxication and post-mortem findings different from those showed by animals intoxicated by known cyanotoxins. We report here the alterations caused by G. amphibium methanolic extract on mouse microcirculatory network, as seen by in vivo intravital microscopy, besides observations on leukocyte migration, cytokine quantitation, and results of toxicological essays. Our data showed that G. amphibium methanolic extract displayed time- and dose-dependent pro-inflammatory activity, and that at lower doses [125 and 250 mg/kg body weight (b.w.)] increased the leukocyte rolling, caused partial venular stasis, as well as induced an increase in leukocyte counts in the peripheral blood and peritoneal washings. At higher doses (500 and 1000 mg/kg b.w.), the extract caused ischemic injury leading to animal death. As confirmed by mass spectrometric studies and polymyxin B test, the G. amphibium methanolic extract did not contain lipopolysaccharides.
Subject(s)
Animals , Cyanobacteria/classification , Amphibian Venoms/toxicity , Inflammation/classificationABSTRACT
Little is known about the biochemical properties of the non-catalytic domains of snake venom metalloproteinases (SVMPs). The ECD sequence of the disintegrin-like domain (D-domain) has been assigned as the disintegrin motif and, recently, the hyper-variable region (HVR) of the cysteine-rich domain (C-domain) was suggested to constitute a potential protein-protein adhesive interface. Here we show that the recombinant C-domain of HF3, a hemorrhagic SVMP from Bothrops jararaca, as well as three peptides resembling its HVR, inhibit collagen-induced platelet aggregation, which indicates a role for the C-domain and its HVR in targeting HF3 to platelets. Site-directed mutagenesis was used for the first time to identify charged residues essential for the functionality of the disintegrin-like/cysteine-rich domains (DC-domains). Residues of the disintegrin loop (E467 and D469), and of the HVR (K568, K569 and K575) of HF3 were individually mutated to Ala. Interestingly, only the mutant D469A was obtained in soluble form in Escherichia coli and this single mutation caused loss of two functional activities of the DC-domains: inhibition of platelet aggregation and increase of leukocyte rolling in the microcirculation. In summary we demonstrate that the C-domain and its HVR are critical for HF3 to affect platelets and leukocytes, however, the disintegrin loop may be important for the functionality of the D-domain in the context of the C-domain.
Subject(s)
Animals , Snake Venoms , LeukocytesABSTRACT
No Estado do Ceará (1992 a 2002), 16 casos de envenenamento com o Thalassophyne nattereri ocorreram no litoral, a maioria (87,5 por cento) em praias de Fortaleza e 12,5 por cento do interior. Noventa e quatro por cento eram do sexo masculino e 6 por cento feminino. Com relacão à idade, 75 por cento estavam na faixa etária de 21 a 40 anos, 19 por cento entre 41 e 60 anos e 6 por cento entre 1 a 10 anos. O tempo de exposicão foi de 1 a 5 horas (4), 6 a 12 (3), mais de 12 horas (4), 5 pacientes não informaram o tempo decorrido entre o acidente e o atendimento. Manifestacões clínicas observadas foram dor, edema local, isquemia transitória, parestesia, equimose e sensacão de queimacão local. O tratamento consistiu de antiinflamatórios e analgésicos. Em alguns casos, foram usados anestésicos, água morna, debridamento cirúrgico e anti-histamínicos. Em 75 por cento dos casos, observou-se cura confirmada e em 12 por cento a cura não foi confirmada, em dois a evolucão foi ignorada. Provavelmente, o número de acidentes ocorridos é maior do que o encontrado devido a subnotificacão.
Subject(s)
Infant , Child, Preschool , Child , Adult , Middle Aged , Animals , Humans , Male , Female , Accidents/statistics & numerical data , Batrachoidiformes , Fish Venoms/poisoning , Brazil/epidemiology , Retrospective Studies , Time FactorsABSTRACT
In Ceará State (1992 to 2002) 16 cases of envenomation by Thalassophryne nattereri occurred in the seaside of Ceará, 87.5% of cases in the region of Fortaleza and 12.5% in the interior of Ceará State. Ninety four percent were men and 6% women. Age range: 75% between 21 and 40 years and 19% between 41 and 60 years old. The time between medical assistance and the accident varied from 1 to 5 hours (4 cases), 6 to 12 hours (3 cases), over 12 hours in 4 cases and 5 patients did not know. Clinical manifestations observed were pain, local edema, transitory ischemia, paresthesia, ecchymosis and burned skin sensation. Anti inflammatory and analgesic drugs were used. In some cases, anesthetic, hot water, surgical peeling and anti-histaminic drugs were used. In 75% of cases cure was confirmed and in 12% cure was not confirmed. The number of accidents is probably higher than was found due to subnotification.
Subject(s)
Batrachoidiformes , Fish Venoms/poisoning , Adult , Animals , Brazil/epidemiology , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Retrospective Studies , Time FactorsABSTRACT
Os acidentes causados por animais marinhos ou fluviais são denominados de ictismo, e seu mecanismo fisiopatológico, é pouco conhecido. As vítimas mais freqüentes de acidentes provocados pelo T. nattereri são os pescadores, que têm suas atividades laborativas impedidas pelo edema, dores intensas e/ou seqüelas funcionais. Avaliação clínica dos pescadores acidentados com o T. nattereri, um estudo dos principais efeitos tóxicos presentes no veneno (dor, edema e necrose) e a avaliação da potencialidade de um antissoro produzido em coelhos para neutralizar in vitro as atividades tóxicas do veneno. Após a captura do peixe é feita a extração da peçonha, determinando-se suas atividades nociveptivas, edematogênicas e necrosantes. Coelhos foram imunizados para a obtenção do soro antiveneno do T. nattereri. Foi realizado o acompanhamento clinicoterapêutico dos pacientes acidentados. Tanto clínica quanto experimentalmente as atividades dolorosas e edematogênicas foram as mais relevantes, e a atividade necrótica só foi observada após inoculação mais concentrada do veneno. O soro antiveneno obtido pela imunização de coelhos foi capaz de neutralizar atividades dolorosas necrosantes
Subject(s)
Humans , Male , Aquatic Fauna , Fishes , Fishes, PoisonousABSTRACT
O acolhimento veio para estruturar o serviço, que ainda é médico centralista. Pretende-se com a implantação do acolhimento eliminar ou diminuir as filas de espera e a demanda reprimida sempre crescente, e com isso melhorar a satisfação dos usuários e da equipe de saúde. Acolher é fazer uma escuta inteligente ao usuário, oferecer cuidado, respeito, e principalmente a resolução dos seus problemas. O acolhimento não é uma sala de espera, uma recepção, é a atitude de ouvir o paciente, responder seus questionamentos, ajudá-lo em todos os pontos de atenção. O acesso à Unidade Básica de Saúde é fundamental. Sem acesso não há acolhimento. O Estado deve garantir ao usuário o fácil acesso às unidades de saúde, com segurança e conforto a todos, bem como trabalhadores capacitados e tecnologia avançada. O profissional deve ser valorizado nessa função de acolher o usuário através de reconhecimento profissional, capacitação e melhores salários, uma vez que acolher gera desgaste e cansaço profissional ao longo do dia-a-dia de trabalho.
