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991.
Radhouani H Igrejas G Carvalho C Pinto L Gonçalves A Lopez M Sargo R Cardoso L Martinho A Rego V Rodrigues R Torres C Poeta P 《Journal of wildlife diseases》2011,47(3):769-773
Fourteen vanA-containing enterococcal isolates were detected in seven of 52 fecal samples (13.5%) from free-ranging red foxes in Portugal. Nine of the vanA-containing isolates were Enterococcus faecium and five were E. durans. Both sequence types, ST262 and ST273, were identified among E. faecium isolates. 相似文献
992.
Johansson HE Johansson MK Wong AC Armstrong ES Peterson EJ Grant RE Roy MA Reddington MV Cook RM 《Applied and environmental microbiology》2011,77(12):4223-4225
The group II azoreductase BTI1 utilizes NADPH to directly cleave azo bonds in water-soluble azo dyes, including quenchers of fluorescence. Unexpectedly, optimal reduction was dye specific, ranging from a pH of <5.5 for Janus green B, to pH 6.0 for methyl red, methyl orange, and BHQ-10, to pH >8.3 for flame orange. 相似文献
993.
Oliveira JH Gonçalves RL Oliveira GA Oliveira PL Oliveira MF Barillas-Mury C 《Insect biochemistry and molecular biology》2011,41(6):349-355
Previous studies showed that Anopheles gambiae L3-5 females, which are refractory (R) to Plasmodium infection, express higher levels of genes involved in redox-metabolism and mitochondrial respiration than susceptible (S) G3 females. Our studies revealed that R females have reduced longevity, faster utilization of lipid reserves, impaired mitochondrial state-3 respiration, increased rate of mitochondrial electron leak and higher expression levels of several glycolytic enzyme genes. Furthermore, when state-3 respiration was reduced in S females by silencing expression of the adenine nucleotide translocator (ANT), hydrogen peroxide generation was higher and the mRNA levels of lactate dehydrogenase increased in the midgut, while the prevalence and intensity of Plasmodium berghei infection were significantly reduced. We conclude that there are broad metabolic differences between R and S An. gambiae mosquitoes that influence their susceptibility to Plasmodium infection. 相似文献
994.
Ewers RM Didham RK Fahrig L Ferraz G Hector A Holt RD Kapos V Reynolds G Sinun W Snaddon JL Turner EC 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2011,366(1582):3292-3302
Opportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah, Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecologists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification. 相似文献
995.
Miele M Sharma A Capone F Raucci R Guerriero E Colonna G Castello G Stasio MD Costantini S 《Bioinformation》2011,6(5):207-208
The cytokines/related receptors system represents a complex regulatory network that is involved in those chronic inflammatory processes which lead to many diseases as cancers. We developed a Cytokine Receptor Database (CytReD) to collect information on cytokine receptors related to their biological activity, gene data, protein structures and diseases in which these and their ligands are implicated. This large set of information may be used by researchers as well as by physicians or clinicians to identify which cytokines, reported in the literature, are important in a given disease and, therefore, useful for purposes of diagnosis or prognostic. AVAILABILITY: The database is available for free at http://www.cro-m.eu/CytReD/ 相似文献
996.
Real E Faure S Donnadieu E Delon J 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(9):5649-5652
Leukocyte locomotion is a polarized process with diverse regulatory assemblies segregating along an anterior-posterior axis that defines two regions within the cell, the leading edge and the uropod. However, the mechanisms that generate T cell asymmetry downstream of chemokine receptors are ill defined. In this study we show that the atypical protein kinases C (aPKCs), PKCiota and PKCzeta, are required for an early symmetry breaking step. Once the polarity is established, aPKCs also drive uropod formation. These effects depend on the interaction between Par6 and aPKCs. Finally, failure to transduce aPKC-dependent signals reduces T cell motility and their ability to scan dendritic cells. Altogether, our findings suggest that lymphocyte motor activity is regulated by a signaling cascade that relays chemokinetic input to aPKCs. 相似文献
997.
Gonçalves RB Mendes YS Soares MR Katpally U Smith TJ Silva JL Oliveira AC 《Journal of molecular biology》2007,366(1):295-306
Rhinoviruses are the major causative agents of the common cold in humans. Here, we studied the stability of human rhinovirus type 14 (HRV14) under conditions of high hydrostatic pressure, low temperature, and urea in the absence and presence of an antiviral drug. Capsid dissociation and changes in the protein conformation were monitored by fluorescence spectroscopy, light scattering, circular dichroism, gel filtration chromatography, mass spectrometry and infectivity assays. The data show that high pressure induces the dissociation of HRV14 and that this process is inhibited by WIN 52084. MALDI-TOF mass spectrometry experiments demonstrate that VP4, the most internal viral protein, is released from the capsid by pressure treatment. This release of VP4 is concomitant with loss of infectivity. Our studies also show that at least one antiviral effect of the WIN drugs involves the locking of VP4 inside the capsid by blocking the dynamics associated with cell attachment. 相似文献
998.
Mazzanti CM Spanevello RM Morsch A Zanin R Battisti V Ahmed M Gonçalves JF Mazzanti A Graça DL Morsch VM Schetinger MR 《Life sciences》2007,81(3):241-248
Many aspects of the relationship between the demyelinating pathology and platelet function need to be elucidated. Thus, the activity of NTPDase and 5'-nucleotidase enzymes was analyzed in platelets from rats demyelinated with ethidium bromide (EB) and previously treated with ebselen (Ebs) and vitamin E (Vit. E). The animals were divided into four groups: for ebselen, the groups were: I-control (saline), II-(saline and Ebs), III-(EB) and IV-(EB and Ebs); and for vitamin E, the groups were: I - control (saline), II-(saline and Vit. E), III-(EB) and IV-(EB and Vit. E). After 3 and 21 days, the blood was collected and the platelets were separated for enzymatic assays. For the treatment with Ebs, the NTPDase activity for ATP substrate was significantly lower in groups II, III and IV (p < 0.05) after 3 days, while after 21 days, a reduction was observed in group III (p < 0.05). ADP hydrolysis was reduced in group II (p < 0.05) and increased in group IV (p < 0.05) after 3 days, while after 21 days there was an increase in group IV (p < 0.05). In the treatment with Vit. E, ATP hydrolysis was lower in groups II, III and IV (p < 0.05) after 3 and 21 days. ADP hydrolysis was increased in group II (p < 0.05) after 3 days, and in group IV (p < 0.05) after 21 days. However, 5'-nucleotidase activity was not altered by the treatments. These findings demonstrate that NTPDase activity in platelets is diminished in demyelinating events and the treatments with Ebs and Vit. E modulated adenine nucleotide hydrolysis. 相似文献
999.
A method for extracting plant roots from soil which facilitates rapid sample processing without compromising measurement accuracy 总被引:1,自引:0,他引:1
Metcalfe DB Williams M Aragão LE da Costa AC de Almeida SS Braga AP Gonçalves PH de Athaydes J Junior S Malhi Y Meir P 《The New phytologist》2007,174(3):697-703
This study evaluates a novel method for extracting roots from soil samples and applies it to estimate standing crop root mass (+/- confidence intervals) in an eastern Amazon rainforest. Roots were manually extracted from soil cores over a period of 40 min, which was split into 10 min time intervals. The pattern of cumulative extraction over time was used to predict root extraction beyond 40 min. A maximum-likelihood approach was used to calculate confidence intervals. The temporal prediction method added 21-32% to initial estimates of standing crop root mass. According to predictions, complete manual root extraction from 18 samples would have taken c. 239 h, compared with 12 h using the prediction method. Uncertainties (percentage difference between mean, and 10th and 90th percentiles) introduced by the prediction method were small (12-15%), compared with uncertainties caused by spatial variation in root mass (72-191%, for nine samples per plot surveyed). This method provides a way of increasing the number of root samples processed per unit time, without compromising measurement accuracy. 相似文献
1000.
M. Teresa Gonçalves Susana C. Gonçalves António Portugal Sandra Silva José Paulo Sousa Helena Freitas 《Plant and Soil》2007,293(1-2):177-188
An experimental assessment of the defence hypothesis of nickel (Ni) hyperaccumulation in Alyssum was lacking. Also, to date no study had investigated the effects of hyperaccumulator litter on a detritivore species. We
performed several experiments with model arthropods representatives of two trophic levels: Tribolium castaneum (herbivore) and Porcellio dilatatus (detritivore). In no-choice trials using artificial food disks with different Ni concentrations, T. castaneum fed significantly less as Ni concentration increased and totally rejected disks with the highest Ni concentration. In choice
tests, insects preferred disks without Ni. In the no-choice experiment, mortality was low and did not differ significantly
among treatments. Hence, this suggested a deterrent effect of high Ni diet. Experiments with P. dilatatus showed that isopods fed A. pintodasilvae litter showed significantly greater mortality (83%) than isopods fed litter from the non-hyperaccumulator species Iberis procumbens (8%), Micromeria juliana (no mortality) or Alnus glutinosa (no mortality). Also, isopods consumed significantly greater amounts of litter from the non-hyperaccumulator plant species.
The behaviour of isopods fed A. pintodasilvae litter suggested an antifeedant effect of Ni, possibly due to post-ingestive toxic effects. Our results support the view
that Ni defends the Portuguese serpentine hyperaccumulator A. pintodasilvae against herbivores, indicating that Ni can account both for feeding deterrence and toxic effects. The effects of hyperaccumulator
litter on the detritivore P. dilatatus suggest that the activity of these important organisms may be significantly impaired with potential consequences on the decomposition
processes. 相似文献