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191.
L. Zappalà G. Siscaro A. Biondi O. Mollá J. González‐Cabrera A. Urbaneja 《Journal of Applied Entomology》2012,136(6):401-409
The South American tomato pinworm, Tuta absoluta (Meyrick), is one of the major pests of tomato crop. Since its detection in the Mediterranean basin, it has been commonly controlled using chemical insecticides. However, inoculation and conservation of predatory mirids, integrated with sprays of selective insecticides, has been demonstrated to be a cost‐effective strategy for controlling this pest. In this work, we tested the efficacy of two sulphur formulations, dustable and wettable powder, for controlling T. absoluta on tomato under greenhouse and open‐field conditions. In addition, the side effects of both sulphur formulations on the predator, Nesidiocoris tenuis (Reuter), were evaluated under laboratory conditions. Dustable sulphur, applied weekly on tomato seedlings artificially infested with T. absoluta in greenhouse conditions, significantly reduced the infestation levels and was demonstrated to have a repellent effect on oviposition. Wettable sulphur was not effective for controlling T. absoluta populations in both greenhouse and open‐field experiments. In the side effect trials conducted with N. tenuis, only dustable sulphur resulted in being moderately harmful as a fresh residue and slightly harmful as a 7‐day‐old residue; no effects were recorded exposing the predator to 14‐day‐old sulphur residues. In contrast, wettable sulphur was classified as harmless to N. tenuis. Our results suggest that the use of sulphur, especially as dustable powder, could be considered as a tool in T. absoluta management strategies, although its side effects on N. tenuis should be taken into account. The implications of these results for the use of sulphur formulations in pest and disease management programmes in tomato crops are discussed. 相似文献
192.
Gallego X Molas S Amador-Arjona A Marks MJ Robles N Murtra P Armengol L Fernández-Montes RD Gratacòs M Pumarola M Cabrera R Maldonado R Sabrià J Estivill X Dierssen M 《Amino acids》2012,43(2):897-909
Nicotinic acetylcholine receptors (nAChRs) are ligand-gated pentameric ion channels that account for the effects of nicotine. Recent genetic studies have highlighted the importance of variants of the CHRNA5/A3/B4 genomic cluster in human nicotine dependence. Among these genetic variants those found in non-coding segments of the cluster may contribute to the pathophysiology of tobacco use through alterations in the expression of these genes. To discern the in vivo effects of the cluster, we generated a transgenic mouse overexpressing the human CHRNA5/A3/B4 cluster using a bacterial artificial chromosome. Transgenic mice showed increased functional α3β4-nAChRs in brain regions where these subunits are highly expressed under normal physiological conditions. Moreover, they exhibited increased sensitivity to the pharmacological effects of nicotine along with higher activation of the medial habenula and reduced activation of dopaminergic neurons in the ventral tegmental area after acute nicotine administration. Importantly, transgenic mice showed increased acquisition of nicotine self-administration (0.015 mg/kg per infusion) and a differential response in the progressive ratio test. Our study provides the first in vivo evidence of the involvement of the CHRNA5/A3/B4 genomic cluster in nicotine addiction through modifying the activity of brain regions responsible for the balance between the rewarding and the aversive properties of this drug. 相似文献
193.
194.
Armentano RL Santana DB Cabrera Fischer EI Graf S Cámpos HP Germán YZ Carmen Saldías MD Alvarez I 《Cryobiology》2006,52(1):17-26
The surgical options in arterial reconstruction are: the use of autologous arteries; autologous veins; or expanded polytetrafluoroethylene (ePTFE) grafts. However, the development of intimal hyperplasia when using veins or ePTFE grafts has been associated with graft failure. Since autologous arteries are not always available, the use of cryopreserved arteries has to be considered. The aims of this study were: (a) to compare the viscoelastic properties of stored cryopreserved arteries and fresh arteries by in vitro analysis; and (b) to compare the viscoelastic properties of arteries measured non-invasively in normotensive patients, with fresh arteries, cryopreserved arteries, and ePTFE segments. The viscoelastic studies were performed in normotensive patients using stress-strain analysis with non-invasive measurement of pressure and diameter in the common carotid artery, and in vitro measurements of pressure and diameter in arteries and prostheses. The in vitro studies showed that the elastic modulus (E), viscous modulus (eta), Stiffness Index (SI), Peterson modulus (Ep), and the pulse wave velocity (PWV) values for human cryopreserved carotid arteries were similar to the values obtained non-invasively in normotensive subjects (P>0.05) and to human fresh vessels (P>0.05). In vitro, the SI, Ep, PWV, and E values of ePTFE were significantly higher than the observed values in subjects and with fresh and cryopreserved arteries (P<0.05); on the other hand the ePTFE eta values were the lowest (P<0.05). We concluded that cryopreserved arteries have similar viscoelastic properties to those obtained in vivo in the arteries of normotensive subjects and in vitro in fresh arteries. Consequently, we conclude that the cryopreservation procedure does not modify the mechanical properties of the arterial wall. 相似文献
195.
Lourdes Cabrera 《Inorganica chimica acta》2006,359(9):3066-3071
Trityl borate salts [4-RPyCPh3][B(C6F5)4] (R = H 1, tBu 2, Et 3, NMe24) and [R3PCPh3][B(C6F5)4] (R = Me 5, nBu 6, Ph[1] 7, p-MeC6H48) are readily prepared via equimolar reaction of the appropriate pyridine or phosphine and trityl borate [CPh3][B(C6F5)4]. The analogous reactions of PiPr3 affords the product [(p-iPr3P-C6H4)Ph2CH][B(C6F5)4] (9) while the corresponding reactions of Cy3P and tBu3P gave the cyclohexadienyl derivatives [(p-R3PC6H5)CPh2][B(C6F5)4] (R = Cy 10, tBu 11). X-ray structures of 5 and 9 are reported. 相似文献
196.
Bardor M Cabrera G Rudd PM Dwek RA Cremata JA Lerouge P 《Current opinion in structural biology》2006,16(5):576-583
Plants are attractive hosts for the production of recombinant proteins. However, their inability to process authentic human N-glycan structures imposes a major limitation on their use as expression systems for therapeutic products. Several strategies have emerged to engineer plant N-glycans into human-compatible molecules. In this context, fast and reliable analytical strategies for the identification of plant N-glycan profiles have been developed to define the N-glycosylation pathways of crops, to monitor the production of plant-made pharmaceuticals and to assess in planta remodelling strategies. 相似文献
197.
Chen JJ Thakur KD Clark MP Laughlin SK George KM Bookland RG Davis JR Cabrera EJ Easwaran V De B George Zhang Y 《Bioorganic & medicinal chemistry letters》2006,16(21):5633-5638
A new class of pyrimidine-based Janus tyrosine kinase 3 (JAK3) inhibitors are described. Many of these inhibitors showed low nanomolar activity against JAK3. 相似文献
198.
Ana R. Cabrera Sayed M.S. Khalil Daniel E. Sonenshine 《Journal of insect physiology》2009,55(7):655-661
In mites, vitellogenin synthesis, regulation and uptake by the oocytes as vitellin remain practically unknown. Although a partial sequence of the gene is now available, no previous studies have been conducted that describe the native vitellin protein in mites. The objective of this study was to characterize vitellin in the twospotted spider mite, Tetranychus urticae. The native twospotted spider mite vitellin migrated as a single major band with a molecular weight of 476 ± 14.5 kDa as compared to 590 ± 25.5 kDa for vitellin from the American dog tick, Dermacentor variabilis. However, isoelectric focusing analysis of native spider mite vitellin showed five bands with pI values slightly acidic to neutral (pH 5.8, 6.2, 6.7, 7.0 and 7.2), as is the case for insect and tick vitellins. Reducing conditions (SDS-PAGE) also revealed multiple subunits ranging from 290.9 to 3.6 kDa and was similar to that found in D. variabilis. Spider mite vitellin weakly bound lipids and carbohydrates compared to the tick. Unlike D. variabilis, the spider mite egg yolk protein does not bind heme. The significance of non-heme binding in mites is discussed. 相似文献
199.
David Metzgar Darcie Baynes Christian J. Hansen Erin A. McDonough Daisy R. Cabrera Melody M. Ellorin Patrick J. Blair Kevin L. Russell Dennis J. Faix 《PloS one》2009,4(9)
Background
Group A Streptococcus pyogenes (GAS) exhibits a high degree of clinically relevant phenotypic diversity. Strains vary widely in terms of antibiotic resistance (AbR), clinical severity, and transmission rate. Currently, strain identification is achieved by emm typing (direct sequencing of the genomic segment coding for the antigenic portion of the M protein) or by multilocus genotyping methods. Phenotype analysis, including critical AbR typing, is generally achieved by much slower and more laborious direct culture-based methods.Methodology/Principal Findings
We compare genotype identification (by emm typing and PCR/ESI-MS) with directly measured phenotypes (AbR and outbreak associations) for 802 clinical isolates of GAS collected from symptomatic patients over a period of 6 years at 10 military facilities in the United States. All independent strain characterization methods are highly correlated. This shows that recombination, horizontal transfer, and other forms of reassortment are rare in GAS insofar as housekeeping genes, primary virulence and antibiotic resistance determinants, and the emm gene are concerned. Therefore, genotyping methods offer an efficient way to predict emm type and the associated AbR and virulence phenotypes.Conclusions/Significance
The data presented here, combined with much historical data, suggest that emm typing assays and faster molecular methods that infer emm type from genomic signatures could be used to efficiently infer critical phenotypic characteristics based on robust genotype: phenotype correlations. This, in turn, would enable faster and better-targeted responses during identified outbreaks of constitutively resistant or particularly virulent emm types. 相似文献200.
A new tetrapeptide D ‐Phe‐L ‐Val‐D ‐Val‐L ‐Tyr ( 1 ), along with three known diketopiperazines and pseurotin A, were isolated from the culture of Penicillium canescens, collected from pollen from beehives, in a screening for new antimicrobial products from unexplored sources. The structure of the tetrapeptide, which exhibits antifungal activity comparable with that of the commercial product benomyl against the soybean phytopathogen Fusarium virguliforme, was determined by spectroscopic (2D‐NMR, and MS and MS/MS) and chemical methods, and the sequence was confirmed by comparison with authentic synthetic isomeric peptides. 相似文献