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171.
Eugênia Barbosa Varella Costa Pedro Henrique de Faria Peres Francisco Grotta-Neto Alexandre Vogliotti Ubiratan Piovezan 《Studies on Neotropical Fauna and Environment》2017,52(1):37-42
Morphometric feces data are used to identify ungulates, but their effectiveness is questioned by numerous authors. Herein, we evaluated the efficiency of this tool in discriminating scat samples from Neotropical deer with sympatric distributions. We performed discriminant analysis of previously identified scat samples (n = 204). The accuracy of discriminant analysis (56–92%) was lower than the confidence limit established in this study in all sympatric combinations expected in these biomes. These results demonstrate serious limitations regarding the use of scat morphometry for species identification of Neotropical deer and reinforce the need to use non-invasive genetic techniques. 相似文献
172.
Baust T Anitei M Czupalla C Parshyna I Bourel L Thiele C Krause E Hoflack B 《Molecular biology of the cell》2008,19(5):1942-1951
The AP-3 adaptor complex targets selected transmembrane proteins to lysosomes and lysosome-related organelles. We reconstituted its preferred interaction with liposomes containing the ADP ribosylation factor (ARF)-1 guanosine triphosphatase (GTPase), specific cargo tails, and phosphatidylinositol-3 phosphate, and then we performed a proteomic screen to identify new proteins supporting its sorting function. We identified ≈30 proteins belonging to three networks regulating either AP-3 coat assembly or septin polymerization or Rab7-dependent lysosomal transport. RNA interference shows that, among these proteins, the ARF-1 exchange factor brefeldin A-inhibited exchange factor 1, the ARF-1 GTPase-activating protein 1, the Cdc42-interacting Cdc42 effector protein 4, an effector of septin-polymerizing GTPases, and the phosphatidylinositol-3 kinase IIIC3 are key components regulating the targeting of lysosomal membrane proteins to lysosomes in vivo. This analysis reveals that these proteins, together with AP-3, play an essential role in protein sorting at early endosomes, thereby regulating the integrity of these organelles. 相似文献
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174.
Sónia Carneiro António L. Amaral Ana C. A. Veloso Teresa Dias António M. Peres Eugénio C. Ferreira Isabel Rocha 《Biotechnology progress》2009,25(3):882-891
The development of monitoring methods for assessing the physiological state of microorganisms during recombinant fermentation processes has been encouraged by the need to evaluate the influence of processing conditions in recombinant protein production. In this work, a technique based on microscopy and image analysis was developed that allows the simultaneous quantification of parameters associated with viability and fluorescent protein production in recombinant Escherichia coli fermentations. Images obtained from light microscopy with phase contrast are used to assess the total number of cells in a given sample and, from epifluorescence microscopy, both protein producing and injured cells are evaluated using two different fluorochromes: propidium iodide and enhanced yellow fluorescent protein. This technique revealed the existence of different cell populations in the recombinant E. coli fermentation broth that were evaluated along four batch fermentations, complementing information obtained with standard techniques to study the effects of the temperature and induction time in recombinant protein production processes. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
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177.
Jaques JA Rezer JF Gonçalves JF Spanevello RM Gutierres JM Pimentel VC Thomé GR Morsch VM Schetinger MR Leal DB 《Cell biochemistry and function》2011,29(8):703-707
With the evidence that curcumin may be a potent neuroprotective agent and that cigarette smoke is associated with a decline in the cognitive performance as our bases, we investigated the activities of Ecto‐Nucleoside Triphosphate Diphosphohydrolase (NTPDase), 5'‐nucleotidase and acetylcholinesterase (AChE) in cerebral cortex synaptosomes from cigarette smoke‐exposed rats treated with curcumin (Cur). The experimental procedures entailed two sets of experiments. In the first set, the groups were vehicle, Cur 12·5, 25 and 50 mg·kg–1; those in the second set were vehicle, smoke, smoke and Cur 12·5, 25 and 50 mg·kg–1. Curcumin prevented the increased NTPDase, 5'‐nucleotidase and AChE activities caused by smoke exposure. We suggest that treatment with Cur was protective because the decrease of ATP and acetylcholine (ACh) concentrations is responsible for cognitive impairment, and both ATP and ACh have key roles in neurotransmission. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
178.
Oliveira AC Peres CM Correia Pires JM Silva Pereira C Vitorino S Figueiredo Marques JJ Barreto Crespo MT San Romão MV 《Microbiological research》2003,158(2):117-124
AIMS: The main aims of this work were the study of cork slabs moulds colonization and the evaluation of the moulds diversity during cork processing steps, in different cork stoppers factories. Simultaneously, it was envisaged to perform an evaluation of the air quality. METHODS AND RESULTS: Moulds were isolated and identified from cork slabs and cork samples in four cork stoppers factories. The identification was based on morphological characters and microscopic observation of the reproductive structures. Airborne spore dispersion was assessed using a two stage Andersen sampler. It was observed that Chrysonilia sitophila was always present on cork slabs during the maturing period, but mould diversity appeared to be associated to the different factory configurations and processing steps. CONCLUSIONS: Spatial separation of the different steps of the process, including physical separation of the maturation step, is essential to guarantee high air quality and appropriate cork slabs colonization, i.e. C. sitophila dominance. The sorting and cutting of the edges of cork slabs after boiling and before the maturing step is also recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is very important for the cork stopper industry as it gives clear indications on how to keep high quality manufacturing standards and how to avoid occupational health problems. 相似文献
179.
Gerrit M. Daubner Anneke Brümmer Cristina Tocchini Stefan Gerhardy Rafal Ciosk Mihaela Zavolan Frédéric H.-T. Allain 《Nucleic acids research》2014,42(12):8092-8105
The STAR family comprises ribonucleic acid (RNA)-binding proteins that play key roles in RNA-regulatory processes. RNA recognition is achieved by a KH domain with an additional α-helix (QUA2) that seems to extend the RNA-binding surface to six nucleotides for SF1 (Homo sapiens) and seven nucleotides for GLD-1 (Caenorhabditis elegans). To understand the structural basis of this probable difference in specificity, we determined the solution structure of GLD-1 KH-QUA2 with the complete consensus sequence identified in the tra-2 gene. Compared to SF1, the GLD-1 KH-QUA2 interface adopts a different conformation resulting indeed in an additional sequence-specific binding pocket for a uracil at the 5′end. The functional relevance of this binding pocket is emphasized by our bioinformatics analysis showing that GLD-1 binding sites with this 5′end uracil are more predictive for the functional response of the messenger RNAs to gld-1 knockout. We further reveal the importance of the KH-QUA2 interface in vitro and that its alteration in vivo affects the level of translational repression dependent on the sequence of the GLD-1 binding motif. In conclusion, we demonstrate that the QUA2 domain distinguishes GLD-1 from other members of the STAR family and contributes more generally to the modulation of RNA-binding affinity and specificity of KH domain containing proteins. 相似文献
180.
Ecology in the age of DNA barcoding: the resource,the promise and the challenges ahead 总被引:3,自引:0,他引:3
Annie Archambault Anne Bruneau Alison Derry Steven W. Kembel Pedro Peres‐Neto Jana Vamosi Terry A. Wheeler 《Molecular ecology resources》2014,14(2):221-232
Ten years after DNA barcoding was initially suggested as a tool to identify species, millions of barcode sequences from more than 1100 species are available in public databases. While several studies have reviewed the methods and potential applications of DNA barcoding, most have focused on species identification and discovery, and relatively few have addressed applications of DNA barcoding data to ecology. These data, and the associated information on the evolutionary histories of taxa that they can provide, offer great opportunities for ecologists to investigate questions that were previously difficult or impossible to address. We present an overview of potential uses of DNA barcoding relevant in the age of ecoinformatics, including applications in community ecology, species invasion, macroevolution, trait evolution, food webs and trophic interactions, metacommunities, and spatial ecology. We also outline some of the challenges and potential advances in DNA barcoding that lie ahead. 相似文献