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111.
The stridulatory organ of the Crematogaster scutellaris (Olivier 1792) workers is being described, comparing their pars stridens present in six nests of this species, with one nest of Crematogaster auberti Emery 1869 and with the bibliographical data regarding other neighbouring species at our disposal. Both species and some Crematogaster scutellaris nests have shown significant differences. We propose several hypotheses which could explain these differences. 相似文献
112.
Alexandre G. Rodrigues Liu Yu Ping Priscyla D. Marcato Oswaldo L. Alves Maria C. P. Silva Rita C. Ruiz Itamar S. Melo Ljubica Tasic Ana O. De Souza 《Applied microbiology and biotechnology》2013,97(2):775-782
Aspergillus tubingensis and Bionectria ochroleuca showed excellent extracellular ability to synthesize silver nanoparticles (Ag NP), spherical in shape and 35?±?10 nm in size. Ag NP were characterized by transmission electron microscopy, X-ray diffraction analysis, and photon correlation spectroscopy for particle size and zeta potential. Proteins present in the fungal filtrate and in Ag NP dispersion were analyzed by electrophoresis (sodium dodecyl sulfate polyacrylamide gel electrophoresis). Ag NP showed pronounced antifungal activity against Candida sp, frequently occurring in hospital infections, with minimal inhibitory concentration in the range of 0.11–1.75 μg/mL. Regarding antibacterial activity, nanoparticles produced by A. tubingensis were more effective compared to the other fungus, inhibiting 98.0 % of Pseudomonas. aeruginosa growth at 0.28 μg/mL. A. tubingensis synthesized Ag NP with surprisingly high and positive surface potential, differing greatly from all known fungi. These data open the possibility of obtaining biogenic Ag NP with positive surface potential and new applications. 相似文献
113.
Romeo A. Saldaña‐Vázquez Alejandro A. Castro‐Luna Cesar A. Sandoval‐Ruiz Jesús R. Hernández‐Montero Kathryn E. Stoner 《Biotropica》2013,45(3):351-356
Studies comparing the abundance of frugivorous bats in shade‐coffee plantations and forest fragments report contradictory results, and have not taken into account the landscape context in which coffee plantations are immersed. Variables of population composition such as abundance, sex proportion, and reproductive condition, together with biological tags (i.e., bat fly prevalence), can provide information about spatiotemporal dynamics of habitats used by bats. In the central part of Veracruz, Mexico, we compared population variables and ectoparasite prevalence of the highland yellow‐shouldered bat (Sturnira ludovici) in two landscapes, one dominated by shade‐coffee plantations and another by forest fragments. Comparing these attributes between these two landscapes will increase our knowledge about the role of this agro‐ecosystem in the conservation of this species, which is an important seed disperser of cloud forest vegetation. Total abundance and proportion of females was greater in forest fragments than in coffee plantations, whereas the percentage of reproductive females and bat fly prevalence was similar between landscapes. Our results show that landscapes with forest fragments harbor the greatest abundance of S. ludovici, but shade‐coffee plantations also are utilized by S. ludovici and likely adjacent forest remnants provide enough food resources for this species and other frugivores. Moreover, this study provides more evidence documenting the importance of preserving the last cloud forest fragments in the central region of Veracruz, Mexico, and suggests that using shade‐coffee plantations to connect forest fragments may be an effective way of maintaining populations of S. ludovici and likely other volant frugivores. 相似文献
114.
Manuel de Lera Ruiz Junying Zheng Michael Y. Berlin Kevin D. McCormick Robert G. Aslanian Robert West Joyce Hwa Jean Lachowicz Margaret van Heek 《Bioorganic & medicinal chemistry letters》2013,23(21):6004-6009
A novel series of non-imidazole bicyclic and tricyclic histamine H3 receptor antagonists has been discovered. Compound 17 was identified as a centrally penetrant molecule with high receptor occupancy which demonstrates robust oral activity in rodent models of obesity. In addition compound 17 possesses clean CYP and hERG profiles and shows no behavioral changes in the Irwin test. 相似文献
115.
María Fernanda López Claudia Cano-Ramírez Ana K. Cesar-Ayala Enrico A. Ruiz Gerardo Zúñiga 《Insect biochemistry and molecular biology》2013,43(5):417-432
Bark beetles (Curculionidae: Scolytinae) are major cause of woody plants death in the world. They colonize the stem and other parts of trees recognizing host-produced specific compounds (kairomones) and insect pheromones. Bark beetle's antennae and alimentary canal participate in the host selection identifying chemical compounds produced by trees and insects, and also in the metabolism and detoxification of these compounds. The red turpentine beetle (RTB), Dendroctonus valens LeConte, is an unaggressive species that colonize > 40 pine species (Pinaceae) in North and Central America. Several studies suggest that bark beetle cytochrome P450 enzymes are involved in monoterpene oxidation. In this study we identified by means of PCR, cloning, sequencing, and bioinformatic analysis, eleven full-length genes: five CYP4, four CYP6, and two CYP9 in the antennae and gut region of RTB, after stimulation with vapors of monoterpenes: (±)-α-pinene, (R)-(+)-α-pinene, (S)-(?)-β-pinene, (S)-(?)-α-pinene and (+)-3-carene; pine trees volatiles used by RTB as kairomones. The recovered cDNA of these genes vary from 1.5 kb to 1.8 kb and the open frame encodes from 496 to 562 amino acid proteins. The bioinformatic analysis suggests that the majority of P450 proteins encoded by these genes are membrane anchored in the endoplasmic reticulum. RT-qPCR assays showed differential expression of all CYP genes between male and female. The gene expression was dependent of monoterpenes and exposure time, with some of them sex, antennae and gut region specific. Significant differences among monoterpenes, gut region, antennae and exposure time were found. Our results suggest that some of these genes may be involved in the detoxification process of these compounds during tree colonization. 相似文献
116.
Download : Download video (36MB) 相似文献
117.
Ellen?M?Unterwald Michelle?E?Page Timothy?B?Brown Jonathan?S?Miller Marta?Ruiz Karen?A?Pescatore Baoji?Xu Louis?French?Reichardt Joel?Beverley Bin?Tang Heinz?Steiner Elizabeth?A?Thomas Michelle?E?EhrlichEmail author 《Molecular neurodegeneration》2013,8(1):47
Background
The high affinity tyrosine kinase receptor, TrkB, is the primary receptor for brain derived neurotrophic factor (BDNF) and plays an important role in development, maintenance and plasticity of the striatal output medium size spiny neuron. The striatal BDNF/TrkB system is thereby implicated in many physiologic and pathophysiologic processes, the latter including mood disorders, addiction, and Huntington’s disease. We crossed a mouse harboring a transgene directing cre-recombinase expression primarily to postnatal, dorsal striatal medium spiny neurons, to a mouse containing a floxed TrkB allele (fB) mouse designed for deletion of TrkB to determine its role in the adult striatum.Results
We found that there were sexually dimorphic alterations in behaviors in response to stressful situations and drugs of abuse. Significant sex and/or genotype differences were found in the forced swim test of depression-like behaviors, anxiety-like behaviors on the elevated plus maze, and cocaine conditioned reward. Microarray analysis of dorsal striatum revealed significant dysregulation in individual and groups of genes that may contribute to the observed behavioral responses and in some cases, represent previously unidentified downstream targets of TrkB.Conclusions
The data point to a set of behaviors and changes in gene expression following postnatal deletion of TrkB in the dorsal striatum distinct from those in other brain regions.118.
Summary We analyse the fruiting phase of the life cycleof Digitalis thapsi L. We studied the production and size of seeds and capsules, and the interpopulational variability and inter-relationships of these parameters. The capsule volume, number of seeds per capsule, of seeds per individual, and of capsules per individual were inter-related and fairly affected by the medium, whereas seed weight was found to bea more independent character. A germination study showed that the species has agreat germinative capacity and has positive photoblasty. It is non-dormant especially if incubated under experimental conditions close to the climatic conditions of the site of provenance of the samples. An increase in temperature speeds up the process without increasing germinability. The morphological and biometric characteristics of the first stages of development of the species following germination were analysed. It was found that seed weight is not positively correlated with cotyledon length nor with any of the other parameters con-sidered, and that the length of the fifth leaf is a useful parameter to express inter-populational genetic variability. Seedling production in spring seems to be influenced more by physical than by chemical factors. 相似文献
119.
K. Vandepitte O. Honnay J. Mergeay P. Breyne I. Roldán‐Ruiz T. De Meyer 《Molecular ecology resources》2013,13(2):269-275
Single nucleotide polymorphisms SNPs are rapidly replacing anonymous markers in population genomic studies, but their use in non model organisms is hampered by the scarcity of cost‐effective approaches to uncover genome‐wide variation in a comprehensive subset of individuals. The screening of one or only a few individuals induces ascertainment bias. To discover SNPs for a population genomic study of the Pyrenean rocket (Sisymbrium austriacum subsp. chrysanthum), we undertook a pooled RAD‐PE (Restriction site Associated DNA Paired‐End sequencing) approach. RAD tags were generated from the PstI‐digested pooled genomic DNA of 12 individuals sampled across the species distribution range and paired‐end sequenced using Illumina technology to produce ~24.5 Mb of sequences, covering ~7% of the specie's genome. Sequences were assembled into ~76 000 contigs with a mean length of 323 bp (N50 = 357 bp, sequencing depth = 24x). In all, >15 000 SNPs were called, of which 47% were annotated in putative genic regions based on homology with the Arabidopsis thaliana genome. Gene ontology (GO) slim categorization demonstrated that the identified SNPs covered extant genic variation well. The validation of 300 SNPs on a larger set of individuals using a KASPar assay underpinned the utility of pooled RAD‐PE as an inexpensive genome‐wide SNP discovery technique (success rate: 87%). In addition to SNPs, we discovered >600 putative SSR markers. 相似文献
120.
Ivan S. de Melo Maria D. Jimenez-Nu?ez Concepción Iglesias Antonio Campos-Caro David Moreno-Sanchez Felix A. Ruiz Jorge Bolívar 《PloS one》2013,8(3)
NOA36/ZNF330 is an evolutionarily well-preserved protein present in the nucleolus and mitochondria of mammalian cells. We have previously reported that the pro-apoptotic activity of this protein is mediated by a characteristic cysteine-rich domain. We now demonstrate that the nucleolar localization of NOA36 is due to a highly-conserved nucleolar localization signal (NoLS) present in residues 1–33. This NoLS is a sequence containing three clusters of two or three basic amino acids. We fused the amino terminal of NOA36 to eGFP in order to characterize this putative NoLS. We show that a cluster of three lysine residues at positions 3 to 5 within this sequence is critical for the nucleolar localization. We also demonstrate that the sequence as found in human is capable of directing eGFP to the nucleolus in several mammal, fish and insect cells. Moreover, this NoLS is capable of specifically directing the cytosolic yeast enzyme polyphosphatase to the target of the nucleolus of HeLa cells, wherein its enzymatic activity was detected. This NoLS could therefore serve as a very useful tool as a nucleolar marker and for directing particular proteins to the nucleolus in distant animal species. 相似文献