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71.
Yasmin Rubio-Palis Mariapia Bevilacqua Domingo Alberto Medina Jorge Ernesto Moreno Lya Cárdenas Víctor Sánchez Yarys Estrada William Anaya ángela Martínez 《Memórias do Instituto Oswaldo Cruz》2013,108(2):220-228
To explore the effects of deforestation and resulting differences in vegetation and land cover on entomological parameters, such as anopheline species composition, abundance, biting rate, parity and entomological inoculation rate (EIR), three villages were selected in the Lower Caura River Basin, state of Bolívar, Venezuela. All-night mosquito collections were conducted between March 2008-January 2009 using CDC light traps and Mosquito Magnet(r) Liberty Plus. Human landing catches were performed between 06:00 pm-10:00 pm, when anophelines were most active. Four types of vegetation were identified. The Annual Parasite Index was not correlated with the type of vegetation. The least abundantly forested village had the highest anopheline abundance, biting rate and species diversity. Anopheles darlingi and Anopheles nuneztovari were the most abundant species and were collected in all three villages. Both species showed unique biting cycles. The more abundantly forested village of El Palmar reported the highest EIR. The results confirmed previous observations that the impacts of deforestation and resulting changes in vegetation cover on malaria transmission are complex and vary locally. 相似文献
72.
Josué Martínez‐de la Puente Santiago Merino Elisa Lobato Juan Moreno Gustavo Tomás Judith Morales 《Bird Study》2013,60(2):264-267
Capsule Some males brought building materials to nests and females who were paired with such males laid heavier clutches. 相似文献
73.
Several protein transport processes in the cell are mediated by signal sequence peptides located at the N-terminal side of the mature protein sequence. To date, the specific interaction and the stability of these peptides at the amphipathic interface of biological membranes and the relevance of the peptide conformation when they interact with lipids is not clear. We report the surface properties and the peptide–lipid interaction of three signal sequence peptides at the air–NaCl 145 mM interface by using the Langmuir monolayer approach. These synthetic peptides have a natural sequence with a non-periodic amphiphilicity, where hydrophobic and hydrophilic residues are located on opposed sides of the peptide primary sequence. We show that signal sequence peptides form insoluble monolayers of high stability against lateral compression. At close packing, peptide molecular area, surface potential and the high stability of the peptide monolayer are indicative that signal sequence peptides are compatible with a β-sheet conformation at the interface. Structure was confirmed with PM-IRRAS and transmission FT-IR studies. The peptides show lateral miscibility with either POPC (a liquid-expanded lipid) or DPPC (a liquid-condensed lipid) in mixed peptide–lipid monolayers. This indicates that signal sequence peptides studied are laterally miscible with phospholipids independent of the phase state of the lipid. 相似文献
74.
Marjorie Bruder Débora Barbosa Vendramini-Costa João Ernesto de Carvalho Ronaldo Aloise Pilli 《Bioorganic & medicinal chemistry》2013,21(17):5107-5117
The present work describes the preparation of a novel series of compounds based on the structure of goniothalamin (1), a natural styryl lactone with known cytotoxic and antiproliferative activities against a variety of cancer cell lines. A focused library of 17 goniothalamin analogues displaying the 5-methyl-2,5-dihydrofuran-2-one motif were prepared, and their cytotoxicity evaluated. While the analogues bearing methoxy and/or hydroxy groups on the aromatic moiety usually were at least three times less potent than the lead compound (1), ortho and para-trifluoromethyl analogues 10 and 11 exhibited levels of cytotoxicity similar to goniothalamin (1) against most cancer cell lines evaluated. One could suggest that the electronic effect of the trifluoromethyl group activates the inhibitor’s electrophilic site via reduction of the electron density of the α,β-unsaturated ester oxygen atom. These results provide new information on the structure activity relationship of these α,β-unsaturated styryl lactones, thereby further focusing the design of novel candidates. 相似文献
75.
Leonora C. Vilela Angelo R. Torillo Alice T. de Ocampo Ernesto J. del Rosario 《Bioscience, biotechnology, and biochemistry》2013,77(2):235-238
Cellulase was produced by Trichoderma viride in semisolid cultures of rice bran, rice straw and rice hulls. T. viride QM 9414 generally produced higher cellulolytic activity on CM-cellulose (Cx activity) using rice bran-rice hull mixture (2:1 w/w) as substrate compared to strains ITCC 1433 and D 4014. It showed higher Cx activity on rice bran-rice straw mixtures than on rice bran-rice hull mixtures. Maximal extraction of the enzyme from mold bran was obtained with 0.05 m sodium citrate buffer, pH 3.5. 相似文献
76.
Marta Coll Philippe Cury Ernesto Azzurro Michel Bariche Giorgos Bayadas Jose Maria Bellido Christian Chaboud Joachim Claudet Abdel-Fattah El-Sayed Didier Gascuel Leyla Knittweis Carlo Pipitone Yianna Samuel-Rhoads Said Taleb Sergi Tudela Audrey Valls 《Reviews in Fish Biology and Fisheries》2013,23(4):415-434
77.
Ernesto F. Treo Daniel O. Cervantes Edward J. Ciaccio 《Biomedical signal processing and control》2013,8(1):41-49
BackgroundMapping of cardiac electrical activity can be difficult when electrogram morphology is complex. Complex morphology (multiple and changing deflections) causes activation maps to vary when constructed by different analysts, particularly at areas with spatially varying conduction pattern. An algorithm was developed to automatically detect electrogram activation time which is robust to complex morphology.MethodElectrograms, many of which were complex, were collected from 320 canine epicardial border zone sites in five experiments. A library of electrogram activation times were manually marked a priori by two expert analysts. Then an algorithm which combined correlation and error functions was used to compare each input electrogram to library electrogram patterns. The closest match of input to library electrogram was used to estimate activation time. Once activation times at 320 sites were determined, activation maps were automatically constructed on a computerized grid. The algorithm was validated by comparison with activation times determined by the analysts.ResultsThe mean difference between manual and automated marking of activation time in electrograms acquired during reentrant ventricular tachycardia was 2.1 ± 3.9 ms. The mean sensitivity and positive predictive value were 95.9% and 83.8% respectively. The computer-automated marking process was completed within a few seconds and was robust to fractionated electrograms. Measurement error was mostly attributable to 60 Hz noise, which can be rectified with filtering.ConclusionsThe automated algorithm is useful for rapid and accurate automatic marking of multichannel electrograms, some of which may be fractionated, as well as for real-time display of activation maps in clinical electrophysiology or research studies. 相似文献
78.
Catalina Perello Ernesto Llamas Vincent Burlat Miriam Ortiz-Alcaide Michael A. Phillips Pablo Pulido Manuel Rodriguez-Concepcion 《PloS one》2016,11(2)
Plastidial isoprenoids are a diverse group of metabolites with roles in photosynthesis, growth regulation, and interaction with the environment. The methylerythritol 4-phosphate (MEP) pathway produces the metabolic precursors of all types of plastidial isoprenoids. Proteomics studies in Arabidopsis thaliana have shown that all the enzymes of the MEP pathway are localized in the plastid stroma. However, immunoblot analysis of chloroplast subfractions showed that the first two enzymes of the pathway, deoxyxylulose 5-phosphate synthase (DXS) and reductoisomerase (DXR), can also be found in non-stromal fractions. Both transient and stable expression of GFP-tagged DXS and DXR proteins confirmed the presence of the fusion proteins in distinct subplastidial compartments. In particular, DXR-GFP was found to accumulate in relatively large vesicles that could eventually be released from chloroplasts, presumably to be degraded by an autophagy-independent process. Together, we propose that protein-specific mechanisms control the localization and turnover of the first two enzymes of the MEP pathway in Arabidopsis chloroplasts. 相似文献
79.
Karen L. Cheney Andrew White I. Wayan Mudianta Anne E. Winters Michelle Quezada Robert J. Capon Ernesto Mollo Mary J. Garson 《PloS one》2016,11(1)
Natural products play an invaluable role as a starting point in the drug discovery process, and plants and animals use many interesting biologically active natural products as a chemical defense mechanism against predators. Among marine organisms, many nudibranch gastropods are known to derive defensive metabolites from the sponges they eat. Here we investigated the putative sequestration of the toxic compound latrunculin A—a 16-membered macrolide that prevents actin polymerization within cellular processes—which has been identified from sponge sources, by five closely related nudibranch molluscs of the genus Chromodoris. Only latrunculin A was present in the rim of the mantle of these species, where storage reservoirs containing secondary metabolites are located, whilst a variety of secondary metabolites were found in their viscera. The species studied thus selectively accumulate latrunculin A in the part of the mantle that is more exposed to potential predators. This study also demonstrates that latrunculin-containing sponges are not their sole food source. Latrunculin A was found to be several times more potent than other compounds present in these species of nudibranchs when tested by in vitro and in vivo toxicity assays. Anti-feedant assays also indicated that latrunculin A was unpalatable to rock pool shrimps, in a dose-dependent manner. These findings led us to propose that this group of nudibranchs has evolved means both to protect themselves from the toxicity of latrunculin A, and to accumulate this compound in the mantle rim for defensive purposes. The precise mechanism by which the nudibranchs sequester such a potent compound from sponges without disrupting their own key physiological processes is unclear, but this work paves the way for future studies in this direction. Finally, the possible occurrence of both visual and chemosensory Müllerian mimicry in the studied species is discussed. 相似文献
80.
Rebeca Martínez Teresa Núñez de Villavicencio-Díaz Aniel Sánchez Yassel Ramos Jesús Noda Ferro Lázaro Gil González Milagros Méndez Elsa Rodríguez Ernesto Marcos Belinda Sánchez Yordanka Masforrol Hilda Garay Fernando Albericio Lisset Hermida Luis Javier González Eva Vonasek Mario P Estrada Vladimir Besada 《Biochemistry and Biophysics Reports》2016
BackgroundGrowth hormone secretagogues (GHS), among other factors, regulate the release of GH. The biological activity of the secretagogue peptide A233 as a promoter of growth and innate immunity in teleost fish has previously been demonstrated, but its role in the immune system of mammals is not well understood.MethodsThe effect of the peptide was investigated in J774A.2 macrophage cells using a comparative proteomics approach after 6 and 12 h of peptide stimulation.ResultsThe functional analysis of differentially modulated proteins showed that A233 peptide treatment appears to promote activation and ROS-dependent cytotoxic functions in macrophages and enhanced expression of antiviral protein complexes such as MAVS. In accordance with this hypothesis, we found that A233 treatment enhanced superoxide anion production and the IFN-γ level in J774A.2 cells and mouse splenocytes, respectively, and reduced viral load in a dengue virus mouse model of infection.ConclusionsThe growth hormone secretagogue A233 peptide promotes activation of ROS-dependent cytotoxic functions and exerts immunomodulatory effects that enable an antiviral state in a dengue virus mouse model.General SignificanceThe increase of IFN-γ level and the differential modulation of antiviral proteins by the A233 peptide suggest that the molecule could activate an innate immune response with a possible further impact in the treatment of acute and chronic diseases. 相似文献