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51.
Toxicity,behavior impairment,and repellence of essential oils from pepper‐rosmarin and patchouli to termites 下载免费PDF全文
Leandro Bacci Janaína K.A. Lima Ana Paula A. Araújo Arie F. Blank Indira M.A. Silva Abraão A. Santos Ane C.C. Santos Péricles B. Alves Marcelo C. Picanço 《Entomologia Experimentalis et Applicata》2015,156(1):66-76
Plant essential oils are potential sources of insecticidal compounds, but have rarely been explored for their effect on termites. In the present study, we assessed the chemical composition of essential oils of Lippia sidoides Cham. (pepper‐rosmarin; Verbenaceae) and Pogostemon cablin (Blanco) Benth. (patchouli; Lamiacaeae) and evaluated their toxicity, behavioral impairment, and repellence to termite species of the genera Amitermes and Microcerotermes (Isoptera: Termitidae: Termitinae). The main components of essential oils of L. sidoides and P. cablin were thymol (44.6%) and patchouli alcohol (36.6%), respectively. The essential oil of P. cablin was most potent against Amitermes cf. amifer Silvestri and had the lowest LD50 (0.63 μg mg?1). There was no difference in toxicity for Microcerotermes indistinctus Mathews between the essential oils of L. sidoides (LD50 = 1.49 μg mg?1) and P. cablin (LD50 = 1.67 μg mg?1). Pogostemon cablin essential oil was the most toxic to M. indistinctus (LC50 = 0.32 μl ml?1) and A. cf. amifer (LC50 = 0.29 μl ml?1). The essential oils analyzed exhibited high toxicity and repellence to the termites, in addition to reducing behavioral interactions among individuals, thus constituting potential termiticides. 相似文献
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53.
Constanze Bickelmann Rafael Jiménez Michael K. Richardson Marcelo R. Sánchez‐Villagra 《Acta zoologica》2014,95(3):283-289
The humerus of fossorial moles has a highly derived anatomy, reflecting the ecological specialization of these animals for digging. It is short and broad, with enlarged muscle attachment sites and pronounced articulations compared to non‐fossorial sister taxa and other mammals. Both condyles are rotated in opposite directions, resulting in a torsion which is unique among eutherian mammals. The development of this exceptional bone was studied in embryonic stages of the fossorial Iberian mole (Talpa occidentalis) from mesenchymal condensation to incipient ossification based on histological serial sections using 3D reconstruction methods. For comparison, embryonic stages of the semi‐fossorial Japanese shrew mole (Urotrichus talpoides) as well as a sister taxon of moles, the terrestrial North American least shrew (Cryptotis parva), were studied. Results show that the humerus of Talpa already shows its derived anatomy with broadened muscle attachment sites and distinct articulations at early cartilaginous stages, when ossification has just started in the mid‐diaphyseal region. The torsion takes place simultaneously with the medial rotation of the forelimbs. The supracondylar foramen is closed in all studied Talpa embryos, but patent in Cryptotis and Urotrichus. This is an example of developmental penetrance, suggesting that variation of adult elements can be found at early stages as well. 相似文献
54.
Susana M.?GallegoEmail author Marcelo J.?Kogan Claudia E.?Azpilicueta Clara?Pe?a María L.?Tomaro 《Plant Growth Regulation》2005,46(3):267-276
Cadmium (Cd) homeostasis and detoxification in sunflower (Helianthus annuus L.) cells differing in Cd sensitivity/tolerance were studied by analyzing the glutathione-mediated antioxidant mechanism
vis-à-vis phytochelatin biosynthesis in vitro. Calluses exposed to Cd-shock/-acclimatization (150μM) were assayed for oxidative stress, reduced glutathione (GSH), glutathione
disulfide (GSSG), phytochelatins (PCs) and reactive oxygen species (ROS). Although Cd did not induce any oxidative stress
in Cd-tolerant callus (TCd), it generated oxidative stress in Cd-shock callus (SCd) both in terms of lipid peroxidation and
protein oxidation. GSH/GSSG ratio remained similar to control values in the cadmium-acclimatized calluses. However, after
acute treatment, there was a decline in both GSH and GSSG levels in SCd with concomitant reduction in the GSH/GSSG ratio.
Analysis of PCs was performed using HPLC and mass spectrometry methods. PC concentration in TCd were approximately twice those
that in SCd, showing in both cases a 1:2:1 relative proportion for PC n = 2 (PC2): PC n = 3 (PC3): PC n = 4 (PC4). Calluses growing in the presence of Cd developed an increased resistance to paraquat oxidative stress generation.
These results indicated that PCs synthesis was an important mechanism for Cd detoxification in sunflower calluses, but the
capacity to grow in the presence of Cd is related to the tissues ability to maintain high intracellular levels of GSH. 相似文献
55.
An unambiguous, fully ab initio and automated technique denoted AIPAR (ab initio parametrization) implemented in the SJBR program has been proposed to yield intermolecular interaction potentials between polar molecules and water. The AIPAR procedure has been applied to several organic molecules covering a wide range of structure and functional groups, namely methanol, acetone (propanone), methanethiol (methyl mercaptan), imidazole (1,3-diazole), oxazole and furan. The AIPAR-derived sets of parameters compare well with the empirical OPLS ones, mainly when the all-atoms model is employed in the OPLS procedure. Monte Carlo simulations were performed for an aqueous solution of methanol and for an equimolar binary mixture methanol–water using the AIPAR and OPLS parameters. The thermodynamic and geometric results obtained with the parameters obtained with the AIPAR procedure compare favorably with the OPLS simulations, even for the binary mixture, demonstrating the precision, robustness and transferability of the parameters obtained with the AIPAR procedure.Figure Superimposed configurations of water (without the hydrogen atoms) around the methanol molecule obtained with the AGOA procedure. 相似文献
56.
De Sousa LP Brasil BS Silva BM Freitas MH Nogueira SV Ferreira PC Kroon EG Bonjardim CA 《Biochemical and biophysical research communications》2005,329(1):237-245
In this study, we showed that plasminogen (Plg) and plasmin (Pla) bind to lysine-binding sites on cell surface and trigger a signaling pathway that activates the mitogen-activated protein kinase (MAPK) MEK and ERK1/2, which in turn leads to the expression of the primary response genes c-fos and early growth response gene egr-1. Our data show that the Plg/Pla-stimulated steady-state mRNA levels of both genes reached a maximum by 30 min and then returned to basal levels by 1h. The gene induction was sensitive to both pharmacological and genetic inhibition of MEK. Leupeptin, a serine protease inhibitor, suppressed Pla but not Plg-induced c-fos and egr-1 expression, emphasizing the role played by the serine protease activity associated with Pla. Pre-incubation with cholera toxin completely blocked the Plg/Pla-induced gene expression, suggesting that another signaling pathway, which recruits G protein-coupled receptors, may also be involved. Furthermore, Plg/Pla also stimulated AP-1 and EGR-1 DNA-binding activities, which were abrogated by pharmacological inhibition of MEK. Altogether, these results suggest that Plg/Pla stimulates c-fos and egr-1 expression via activation of the MEK/ERK pathway. 相似文献
57.
Barcelos IS Ferreira MS Moura LP Biondi GF Costa-Cruz JM 《Memórias do Instituto Oswaldo Cruz》2005,100(4):427-429
Paired samples of cerebrospinal fluid (CSF) and serum of 30 patients--10 with active, 10 with inactive neurocysticercosis (NCC), and 10 control subjects--were evaluated by enzyme-linked immunosorbent assay (ELISA) using two Taenia crassiceps metacestode extracts as antigen in order to detect IgG antibodies. In active NCC, high levels of IgG were detected (p < 0.05). The CSF samples showed 80% (CI 72-88) of reactivity in the saline extract (S) and 90% (CI 84-95) in sodium dodecyl sulphate (SDS) and the serum samples were reactive in 90% (CI 84-95) and 100% (CI 98-100) in the S and SDS antigenic extracts, respectively. The use of the paired samples of CSF and serum in active NCC showed equivalent results suggesting that the serum samples could be used as a screening in those patients whose CSF puncture is counter-indicated. 相似文献
58.
Ana-Carolina Oliveira Bruna C. de Alencar Fanny Tzelepis Weberton Klezewsky Raquel N. da Silva Fabieni S. Neves Gisele S. Cavalcanti Silvia Boscardin Marise P. Nunes Marcelo F. Santiago Alberto Nóbrega Maurício M. Rodrigues Maria Bellio 《PLoS pathogens》2010,6(4)
The murine model of T. cruzi infection has provided compelling evidence that development of host resistance against intracellular protozoans critically depends on the activation of members of the Toll-like receptor (TLR) family via the MyD88 adaptor molecule. However, the possibility that TLR/MyD88 signaling pathways also control the induction of immunoprotective CD8+ T cell-mediated effector functions has not been investigated to date. We addressed this question by measuring the frequencies of IFN-γ secreting CD8+ T cells specific for H-2Kb-restricted immunodominant peptides as well as the in vivo Ag-specific cytotoxic response in infected animals that are deficient either in TLR2, TLR4, TLR9 or MyD88 signaling pathways. Strikingly, we found that T. cruzi-infected Tlr2−/−, Tlr4−/−, Tlr9−/
− or Myd88−/− mice generated both specific cytotoxic responses and IFN-γ secreting CD8+ T cells at levels comparable to WT mice, although the frequency of IFN-γ+CD4+ cells was diminished in infected Myd88−/− mice. We also analyzed the efficiency of TLR4-driven immune responses against T. cruzi using TLR4-deficient mice on the C57BL genetic background (B6 and B10). Our studies demonstrated that TLR4 signaling is required for optimal production of IFN-γ, TNF-α and nitric oxide (NO) in the spleen of infected animals and, as a consequence, Tlr4−/− mice display higher parasitemia levels. Collectively, our results indicate that TLR4, as well as previously shown for TLR2, TLR9 and MyD88, contributes to the innate immune response and, consequently, resistance in the acute phase of infection, although each of these pathways is not individually essential for the generation of class I-restricted responses against T. cruzi. 相似文献
59.
Marti MA Crespo A Capece L Boechi L Bikiel DE Scherlis DA Estrin DA 《Journal of inorganic biochemistry》2006,100(4):761-770
We present an investigation of the molecular basis of the modulation of oxygen affinity in heme proteins using computer simulation. QM-MM calculations are applied to explore distal and proximal effects on O(2) binding to the heme, while classical molecular dynamics simulations are employed to investigate ligand migration across the polypeptide to the active site. Trends in binding energies and in the kinetic constants are illustrated through a number of selected examples highlighting the virtues and the limitations of the applied methodologies. These examples cover a wide range of O(2)-affinities, and include: the truncated-N and truncated-O hemoglobins from Mycobacterium tuberculosis, the mammalian muscular O(2) storage protein: myoglobin, the hemoglobin from the parasitic nematode Ascaris lumbricoides, the oxygen transporter in the root of leguminous plants: leghemoglobin, the Cerebratulus lacteus nerve tissue hemoglobin, and the Alcaligenes xyloxidans cytochrome c'. 相似文献
60.
Fernando P. F. Zorzenon Arthur F. Tomaseto Matthew P. Daugherty João R. S. Lopes Marcelo P. Miranda 《Journal of Applied Entomology》2021,145(4):326-335
Seasonality often influences multiple aspects of vector-borne plant diseases. With respect to the management of plant disease vectors, an understanding of the factors driving seasonal changes in vector flight activity may improve management outcomes by facilitating more proactive application of control measures. One of the most challenging issues for citrus Huanglongbing management is to forecast when disease primary spread by bacteriliferous Diaphorina citri will occur. We monitored the temporal patterns of immigrating psyllids, using upwards of 1,200 traps spread among 9 citrus farms and checked on a weekly basis over 4 years. This dataset was analysed with a set of hierarchical models to estimate the effect of climatic variables on citrus foliage production (i.e. flush), and effects of climatic variables and citrus foliage dynamics on D. citri catches over the season. The results showed substantial seasonal variability in immigrating D. citri abundance, with the critical dispersal/migration period occurring between end of winter and spring. During this period, 65% of the total psyllids were collected on sticky traps. Seasonality of immigrating D. citri coincided with changes in certain climate variables, with negative effects of humidity and daily maximum temperatures, and a positive effect of rainfall amount in prior weeks. Maximum temperature and both daily minimum temperature and rainfall during prior weeks were also associated with new citrus flush production, which itself was positively related to immigrating D. citri abundance. Based on these results, citrus growers should be aware and intensify the frequency of psyllid control tactics (i.e. insecticide and/or kaolin sprays) during this period in order to prevent Ca. L. asiaticus transmission. These results are an important step towards developing the predictive framework needed to refine D. citri and huanglongbing management. 相似文献