169 research outputs found

    Effect of Methyl Jasmonate on the Performance of Tetranychus evansi Baker & Pritchard, 1960 (Acari: Tetranychidae) and Phytoseiulus longipes Evans, 1968 (Acari: Phytoseiidae) on Tomato Plants

    Get PDF
    Inducible anti-herbivore defenses in plants are predominantly regulated by jasmonic acid (JA). The red spider mite Tetranychus evansi Baker & Pritchard, 1960 (Acari: Tetranychidae) is an invasive pest known for its detrimental impact on tomato plants and other Solanaceae crops. Here, we investigated the extent to which T. evansi and the predatory mite Phytoseiulus longipes Evans, 1968 (Acari: Phytoseiidae) are affected by induced JA-defenses. Initially, we artificially induced the JA-response in tomato plants using exogenous methyl jasmonate (MeJA) and subsequently assessed the effect of JA defenses on spider mite by evaluating mortality and oviposition rates. Our findings revealed a higher mortality and lower oviposition rates on plants treated with MeJA compared to non-treated control plants. Furthermore, we examined the predatory mite's predation rates on spider mite eggs produced on MeJA-treated and non-treated tomato plants. The results showed a reduced predation on T. evansi eggs derived from MeJA-treated plants, indicating a potential negative impact of JA-induced defenses on the predator's performance. Finally, we released five predatory females on T. evansi-infested tomato plants treated and non-treated with MeJA, monitoring the predator population density for three generations. Predator population was not affected, as the abundance of larvae and adults was not significantly different between treatments. These findings underscore the negative impact of JA defenses on herbivores and highlight the trade-off it may pose on natural enemies

    Influência do AIA e AIB no enraizamento do mamoeiro hibrido Tainung 1.

    Get PDF
    Nesta pesquisa estudou-se a influência das concentrações dos ácidos 3-indolil acético (AIA) e idolbutírico (AIB) na indução de rizogênese em mamoeiro híbrido Tainung 1

    Micropropagacao in vitro de plantas tetraploides de melancia a partir de explantes de gemas apicais e axilares.

    Get PDF
    Visando à avaliação de diferentes explantes na micropropagação "in vitro" de melancia (Cítrullus lanatus), foi realizado um experimento no Laboratório de Biotecnologia da Embrapa SemiÁrido, no qual, segmentos do ápice caulinar e das axilas foliares de plantas tetraplóides adultas foram coletados no campo, desinfestados com álcool etílico 70% por 1 min e NaOCI a 1,25% por 20 min

    DNA-Containing Immunocomplexes Promote Inflammasome Assembly and Release of Pyrogenic Cytokines by CD14+ CD16+ CD64high CD32low Inflammatory Monocytes from Malaria Patients

    Get PDF
    High levels of circulating immunocomplexes (ICs) are found in patients with either infectious or sterile inflammation. We report that patients with either Plasmodium falciparum or Plasmodium vivax malaria have increased levels of circulating anti-DNA antibodies and ICs containing parasite DNA. Upon stimulation with malaria-induced ICs, monocytes express an NF-kappaB transcriptional signature. The main source of IC-induced proinflammatory cytokines (i.e., tumor necrosis factor alpha [TNF-alpha] and interleukin-1beta [IL-1beta])in peripheral blood mononuclear cells from acute malaria patients was found to be a CD14(+) CD16 (FcgammaRIIIA)(+) CD64 (FcgammaRI)(high) CD32 (FcgammaRIIB)(low) monocyte subset. Monocytes from convalescent patients were predominantly of the classical phenotype (CD14(+) CD16(-)) that produces high levels of IL-10 and lower levels of TNF-alpha and IL-1beta in response to ICs. Finally, we report a novel role for the proinflammatory activity of ICs by demonstrating their ability to induce inflammasome assembly and caspase-1 activation in human monocytes. These findings illuminate our understanding of the pathogenic role of ICs and monocyte subsets and may be relevant for future development of immunity-based interventions with broad applications to systemic inflammatory diseases. IMPORTANCE: Every year, there are approximately 200 million cases of Plasmodium falciparum and P. vivax malaria, resulting in nearly 1 million deaths, most of which are children. Decades of research on malaria pathogenesis have established that the clinical manifestations are often a consequence of the systemic inflammation elicited by the parasite. Recent studies indicate that parasite DNA is a main proinflammatory component during infection with different Plasmodium species. This finding resembles the mechanism of disease in systemic lupus erythematosus, where host DNA plays a central role in stimulating an inflammatory process and self-damaging reactions. In this study, we disclose the mechanism by which ICs containing Plasmodium DNA activate innate immune cells and consequently stimulate systemic inflammation during acute episodes of malaria. Our results further suggest that Toll-like receptors and inflammasomes have a central role in malaria pathogenesis and provide new insights toward developing novel therapeutic interventions for this devastating disease

    Micropropagação do abacaxizeiro em larga escala.

    Get PDF
    O laboratório de Biotecnologia da Embrapa Semi-Árido produziu mudas de abacaxi híbrido [Ananas comosus (L.) Merril], resultante do cruzamento entre as variedades Primavera e Roxo de Tefé, provenientes da Emepa-PB, objetivando avaliar sua micropropagação massal

    Caspase-8 mediates inflammation and disease in rodent malaria

    Get PDF
    Earlier studies indicate that either the canonical or non-canonical pathways of inflammasome activation have a limited role on malaria pathogenesis. Here, we report that caspase-8 is a central mediator of systemic inflammation, septic shock in the Plasmodium chabaudi-infected mice and the P. berghei-induced experimental cerebral malaria (ECM). Importantly, our results indicate that the combined deficiencies of caspases-8/1/11 or caspase-8/gasdermin-D (GSDM-D) renders mice impaired to produce both TNFalpha and IL-1beta and highly resistant to lethality in these models, disclosing a complementary, but independent role of caspase-8 and caspases-1/11/GSDM-D in the pathogenesis of malaria. Further, we find that monocytes from malaria patients express active caspases-1, -4 and -8 suggesting that these inflammatory caspases may also play a role in the pathogenesis of human disease

    Atributos microbianos do solo sob pastagens naturais com diferentes intensidades de pastejo

    Get PDF
    The soil microbial biomass is the living fraction of organic matter, being responsible for several biological and biochemical processes of the soil and influenced by the conditions imposed by the environment. To evaluate the effect of grazing on changes in soil microbial attributes we studied four grazing intensities based on natural grassland of Pampa Biome: 4, 8, 12 and 16 kg of dry matter per day per 100 kg of animal live weight, compared to an area without grazing. We used randomized block design with two replications. Samples were taken on 11/23/2011 and analyzed to determine the levels of soil organic matter (SOM), microbial biomass, nitrogen, respiration and metabolic quotient. The results showed that at intermediate grazing intensities, such as 12%, minor disturbances occur in soil microbial biomass compared to other intensities, emit less CO2 into the atmosphere for each animal unit produced. The levels of organic matter and soil microbial biomass systems are lower in grazed than in areas excluded from grazing for a long period.A biomassa microbiana do solo constitui a fração viva da matéria orgânica, sendo responsável por diversos processos biológicos e bioquímicos do solo e influenciada pelas condições impostas pelo meio. Visando avaliar o efeito do pastejo nas alterações dos atributos microbianos do solo, foram estudados 4 intensidades de pastejo baseados em pastagem natural do Bioma Pampa: 4, 8, 12 e 16% de oferta de forragem (kg de peso vivo em MS), comparados com uma área sem pastejo. Foi utilizado o delineamento em blocos casualizados com duas repetições. As amostras foram tomadas no dia 23/11/2011, sendo avaliados os teores de matéria orgânica do solo (MOS), biomassa microbiana, nitrogênio, respiração e quociente metabólico. Os resultados apontaram que em intensidades de pastejo intermediárias, como 12%, ocorrem menores distúrbios na biomassa microbiana do solo quando comparados às demais ofertas, emitindo menor quantidade de CO2 para a atmosfera para cada unidade animal produzida. Os teores de matéria orgânica e biomassa microbiana do solo em sistemas pastejados são inferiores àqueles de áreas excluídas do pastejo por um longo período

    Chemical and pharmacological investigation of Solanum species of Brazil: a search for solasodine and other potentially useful therapeutic agents

    Full text link
    A systematic search for solasodine, an important staring material for the partial synthesis of steroidal hormones as well as other potentially bioactive constituents of various Solanum species of Brazil has been undertaken. Thus, the fruits of S. paludosum, S. asperum, S. sessiliforum and Solanum sp. were found to contain significant amounts of solasodine. The root bark of S. paludosum which showe durare like activity yelded tomatidenol and another yet unidentified alkaloid responsible for the biological activity. The fruits of S. asperum yelded a new spirosolane alkaloid, solaparnaine. The stem bark of S. pseudo-quina showed convulsive and exitatory activity from which (25S)-isosolafloridine was identified as the active principle. In addition, the latter alkaloid was also found to show antimicrobial activity

    Curcumin encapsulation in nanostructures for cancer therapy: a 10-year overview

    Get PDF
    Journal pre-proofsCurcumin (CUR) is a phenolic compound present in some herbs, including Curcuma longa Linn. (turmeric rhizome), with a high bioactive capacity and characteristic yellow color. It is mainly used as a spice, although it has been found that CUR has interesting pharmaceutical properties, acting as a natural antioxidant, anti-inflammatory, antimicrobial, and antitumoral agent. Nonetheless, CUR is a hydrophobic compound with low water solubility, poor chemical stability, and fast metabolism, limiting its use as a pharmacological compound. Smart drug delivery systems (DDS) have been used to overcome its low bioavailability and improve its stability. The current work overviews the literature from the past 10 years on the encapsulation of CUR in nanostructured systems, such as micelles, liposomes, niosomes, nanoemulsions, hydrogels, and nanocomplexes, emphasizing its use and ability in cancer therapy. The studies highlighted in this review have shown that these nanoformulations achieved higher solubility, improved tumor cytotoxicity, prolonged CUR release, and reduced side effects, among other interesting advantages.This study was funded by the Coordination for Higher Level Graduate Improvements (CAPES/Brazil, finance code 001), National Council for Scientific and Technological Development (CNPq/Brazil, PIBIC process #123483/2020-4), State of São Paulo Research Foundation (FAPESP/Brazil, processes #2017/10789-1, #2018/10799-0, #2018/06475-4, #2018/07707-6, #2019/08549-8, and #2020/03727-2). This work was also supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and the project AgriFood XXI (NORTE-01-0145-FEDER-000041) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Our Figures were created with BioRenderinfo:eu-repo/semantics/publishedVersio
    corecore