103 research outputs found

    A comprehensive review on recent advances in the use of ethnomedicinal plants and their metabolites in snake bite treatment

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    Snakebites are a severe medical and social issue, particularly in tropical and subtropical countries with minimal medical facilities, where the most dangerous snakes are found. Worldwide, most rural areas use medicinal plants alone or in combination as antidotes for snakebite treatment. Local knowledge of medicinal plants for snakebite treatment plays a more critical role in primary healthcare services in rural areas. As a result of this review, it is revealed that 39% of herbs, 38% of shrubs, 18% of trees, 2% of climbers, 2% of bulbs, and 1% of ferns have snake antivenom potential, which is indicative of the presence of numerous phytochemicals such as alkaloids, coumarins, curcuminoids, flavonoids, steroids, triterpenoids, and cinnamic acid in particular plants. According to the availability of information, the data focus on the plants, their families, and their parts from various literature sources. In the future, the valuable plants reported here and their phytoconstituents may be potential sources for developing effective natural drugs for snake bite treatments. Therefore, this review is a comprehensive study of the snake antivenom potential of various medicinal plants and their bioactive compounds

    Injection of Pseudomonas aeruginosa Exo Toxins into Host Cells Can Be Modulated by Host Factors at the Level of Translocon Assembly and/or Activity

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    Pseudomonas aeruginosa type III secretion apparatus exports and translocates four exotoxins into the cytoplasm of the host cell. The translocation requires two hydrophobic bacterial proteins, PopB and PopD, that are found associated with host cell membranes following infection. In this work we examined the influence of host cell elements on exotoxin translocation efficiency. We developed a quantitative flow cytometry based assay of translocation that used protein fusions between either ExoS or ExoY and the ß-lactamase reporter enzyme. In parallel, association of translocon proteins with host plasma membranes was evaluated by immunodetection of PopB/D following sucrose gradient fractionation of membranes. A pro-myelocytic cell line (HL-60) and a pro-monocytic cell line (U937) were found resistant to toxin injection even though PopB/D associated with host cell plasma membranes. Differentiation of these cells to either macrophage- or neutrophil-like cell lines resulted in injection-sensitive phenotype without significantly changing the level of membrane-inserted translocon proteins. As previous in vitro studies have indicated that the lysis of liposomes by PopB and PopD requires both cholesterol and phosphatidyl-serine, we first examined the role of cholesterol in translocation efficiency. Treatment of sensitive HL-60 cells with methyl-ß-cyclodextrine, a cholesterol-depleting agent, resulted in a diminished injection of ExoS-Bla. Moreover, the PopB translocator was found in the membrane fraction, obtained from sucrose-gradient purifications, containing the lipid-raft marker flotillin. Examination of components of signalling pathways influencing the toxin injection was further assayed through a pharmacological approach. A systematic detection of translocon proteins within host membranes showed that, in addition to membrane composition, some general signalling pathways involved in actin polymerization may be critical for the formation of a functional pore. In conclusion, we provide new insights in regulation of translocation process and suggest possible cross-talks between eukaryotic cell and the pathogen at the level of exotoxin translocation

    Taxocenose de anuros (Amphibia: Anura) em uma área de Floresta Ombrófila Densa no Sul do Brasil

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    A riqueza de espécies, o uso de habitat e a identificação das principais ameaças sobre uma taxocenose de anfíbios anuros foram determinadas ao longo de 19 meses, em uma localidade originalmente coberta de Floresta Ombrófila Densa no município de Morretes, Paraná, Brasil. Foram registradas 32 espécies de anuros pertencentes a 10 famílias. A anurofauna local apresenta 58% das espécies associadas à ambientes de área aberta e 42% associadas à ambientes florestais. Dentre todos os modos reprodutivos registrados, o modo tipo um - ovos e larvas exotróficas em habitats lênticos, foi o mais comum, especialmente em Hylidae. A atividade de desmatamento, que atualmente é umas das causas de maior efeito negativo sobre populações de anfíbios, ocorre a pelo menos 28 anos nessa região. Iniciativas de conservação e o manejo adequado da área são necessários para que a diversidade de anuros possa ser preservada.Assemblage of anurans (Amphibia, Anura) in a locality of dense Atlantic rain forest, Morretes, Paraná, Brazil. The species richness, habitat use and main environmental impacts on a taxocenose of anurans were determined during 19 months, in a region originally covered by dense Atlantic rain forest at Morretes municipality. Thirty-two species of anurans, belonging to ten families, were registered. In the local anuran fauna, 58% of these species were associated with open areas, and 42% of the species were associated to forests. Among all species, the most frequently observed reproductive mode was mode 1 - eggs and exotrophic larvae in lentic water, mainly presented by the family Hylidae. The deforestation, which today has the major negative impact on this amphibian assemblage, is present in the region for at least 28 years. Environmental management programs are necessary to keep the diversity of anurans.Universidade Estadual Paulista Programa de Pós-graduação em Biologia AnimalUniversidade Estadual Paulista Programa de Pós-graduação em Biologia Anima
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