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61.
62.
AMÉLIE VANTAUX SHARON SCHILLEWAERT THOMAS PARMENTIER WIM VAN DEN ENDE JOHAN BILLEN TOM WENSELEERS 《Ecological Entomology》2015,40(5):511-517
1. The aphid Aphis fabae (Scopoli) is facultatively tended by Lasius niger (Linnaeus) ants. Previously, we found that A. fabae colonies can be made up of several clones, and that clones display significant differences in the composition of their honeydew sugars, especially in the amount of the ant attractant sugar melezitose that they produce. 2. These clonal differences could greatly impact the strength of the mutualistic interaction with ants as well as the aphids' fitness. 3. Hence, the aim of this study was to compare the fitness of different A. fabae clones that differed in their melezitose secretion, and whether or not they were tended by ants. 4. Individual fitness indices, colony growth, and alate production of single‐clone aphid colonies were analysed. 5. The results demonstrate that the fitness consequences of ant attendance critically depend on an interaction between levels of melezitose production. In particular, we show that high‐melezitose secreting clones produce fewer alates and hence might have a lower dispersal ability in the presence of ants. 6. Furthermore, these data confirm previous evidence that ant attendance is costly and results in the production of fewer apterae. 相似文献
63.
Johansson AS Brask J Owe-Larsson B Hetta J Lundkvist GB 《Journal of biological rhythms》2011,26(6):541-551
Valproic acid (VPA) is an anticonvulsant used to treat bipolar disorder, a psychiatric disease associated with disturbances in circadian rhythmicity. Little is known about how VPA affects circadian rhythms. The authors cultured tissues containing the master brain pacemaker for circadian rhythmicity, the suprachiasmatic nuclei (SCN), and skin fibroblasts from transgenic PERIOD2::LUCIFERASE (PER2::LUC) mice and studied the effect of VPA on the circadian PER2::LUC rhythm by measuring bioluminescence. VPA (1 mM) significantly phase advanced the PER2::LUC rhythm when applied at a time point corresponding to the lowest (trough, ~ZT 0) PER2::LUC expression but phase delayed the PER2::LUC rhythm when the drug was administered at the time of highest (peak, ~ZT 12) protein expression. In addition, it significantly increased the overall amplitude of PER2::LUC oscillations at time points at or close to ZT 12 but had no effect on period. Real-time PCR analyses on mouse and human fibroblasts revealed that expressions of other clock genes were increased after 2 h treatment with VPA. Because VPA is known to inhibit histone deacetylation, the authors treated cultures with an established histone deacetylation inhibitor, trichostatin A (TSA; 20 ng/mL), to compare the effect of VPA and TSA on molecular rhythmicity. They found that TSA had similar effects on the PER2::LUC rhythm as VPA. Furthermore, VPA and TSA significantly increased acetylation on histone H3 but in comparison little on histone H4. Lithium is another commonly used treatment for bipolar disorder. Therefore, the authors also studied the impact of lithium chloride (LiCl; 10 mM) on the PER2::LUC rhythm. LiCl delayed the phase, but in contrast to VPA and TSA, LiCl lengthened the PER2::LUC period and had no effect on histone acetylation. These results demonstrate that VPA can delay or advance the phase, as well as increase the amplitude, of the PERIOD2::LUCIFERASE rhythm depending on the circadian time of application. Furthermore, the authors show that LiCl delays the phase and lengthens the period of the PER2::LUC rhythm, confirming previous reports on circadian lithium effects. These different molecular effects may underlie differential chronotherapeutic effects of VPA and lithium. 相似文献
64.
AM Fietta AM Bardoni R Salvini I Passadore M Morosini L Cavagna V Codullo E Pozzi F Meloni C Montecucco 《Arthritis research & therapy》2007,8(6):R160
Lung fibrosis is a major cause of mortality and morbidity in systemic sclerosis (SSc). However, its pathogenesis still needs
to be elucidated. We examined whether the alteration of certain proteins in bronchoalveolar lavage fluid (BALF) might have
a protective or a causative role in the lung fibrogenesis process. For this purpose we compared the BALF protein profile obtained
from nine SSc patients with lung fibrosis (SScFib+) with that obtained from six SSc patients without pulmonary fibrosis (SScFib-) by two-dimensional gel electrophoresis (2-DE). Only spots and spot-trains that were consistently expressed in a different
way in the two study groups were taken into consideration. In total, 47 spots and spot-trains, corresponding to 30 previously
identified proteins in human BALF, showed no significant variation between SScFib+ patients and SScFib- patients, whereas 24 spots showed a reproducible significant variation in the two study groups. These latter spots corresponded
to 11 proteins or protein fragments, including serum albumin fragments (13 spots), 5 previously recognized proteins (7 spots),
and 4 proteins (3 spots) that had not been previously described in human BALF maps, namely calumenin, cytohesin-2, cystatin
SN, and mitochondrial DNA topoisomerase 1 (mtDNA TOP1). Mass analysis did not determine one protein-spot. The two study groups
revealed a significant difference in BALF protein composition. Whereas levels of glutathione S-transferase P (GSTP), Cu–Zn
superoxide dismutase (SOD) and cystatin SN were downregulated in SScFib+ patients compared with SScFib- patients, we observed a significant upregulation of α1-acid glycoprotein, haptoglobin-α chain, calgranulin (Cal) B, cytohesin-2,
calumenin, and mtDNA TOP1 in SScFib+ patients. Some of these proteins (GSTP, Cu–Zn SOD, and cystatin SN) seem to be involved in mechanisms that protect lungs
against injury or inflammation, whereas others (Cal B, cytohesin-2, and calumenin) seem to be involved in mechanisms that
drive lung fibrogenesis. Even if the 2-DE analysis of BALF did not provide an exhaustive identification of all BALF proteins,
especially those of low molecular mass, it allows the identification of proteins that might have a role in lung fibrogenesis.
Further longitudinal studies on larger cohorts of patients will be necessary to assess their usefulness as predictive markers
of disease. 相似文献
65.
Flávio B Barros Susana AM Varela Henrique M Pereira Luís Vicente 《Journal of ethnobiology and ethnomedicine》2012,8(1):1-20
Background
Zootherapy inventories are important as they contribute to the world documentation of the prevalence, importance and diversity of the medicinal use of animals in traditional human communities. The present study aims to contribute with a more valuable example of the zootherapy practices of a traditional community in the Brazilian Amazonia ?C the ??Riozinho do Anfrísio?? Extractive Reserve, in Northern Brazil.Methods
We used the methods of participant observation and semi-structured interviews, applied to 25 informants. We employed the combined properties of two indices to measure the medicinal importance of each cited species to the studied community, as well as their versatility in the treatment of diseases: the well known Use Value (UV) and the Medicinal Applications Value (MAV) that we developed.Results
We recorded 31 species of medicinal animals from six taxonomic categories, seven of which are new to science. The species are used for the treatment of 28 diseases and one species is used as an amulet against snakebites. The five species with the highest UV indices are the most popular and valued by the studied community. Their contrasting MAV indices indicate that they have different therapeutic properties: specific (used for the treatment of few diseases; low versatility) and all-purpose (several diseases; high versatility). Similarly, the most cited diseases were also those that could be treated with a larger number of animal species. Ten species are listed in the CITES appendices and 21 are present in the IUCN Red List. The knowledge about the medicinal use of the local fauna is distributed evenly among the different age groups of the informants.Conclusions
This study shows that the local fauna represents an important medicinal resource for the inhabitants of the protected area. The combined use of the UV and MAV indices allowed identifying the species with the highest therapeutic potential. This type of information about a species may be of interest to pharmacological research, and is crucial to its conservation, since it helps signaling the species that may undergo higher hunting pressures. Data on zootherapy can also be of interesting to ecologists by contributing to indicators of local biodiversity richness. 相似文献66.
Seventy-three patients were studied after ingesting a liquid glucose meal, tagged with 113Indium. Nineteen of these patients were awaiting surgery for their duodenal ulcer, while 54 were studied postoperatively, 25 of whom experienced troublesome postprandial (dumping) symptoms in their daily lives. The radioactive marker emptied significantly faster in the symptomatic patients than in the symptomfree, pre and post-operative groups (initial emptying rate 3.45 ± 0.23, compared with 1.16 ± 0.19 and 1.27 ± 0.15% fall in counts/min respectively; p < 0.01). Initial (20 min) rises in the plasma concentrations of neurotensin-like immunoreactivity measured during the test correlated significantly with the rate of gastric emptying in all patients, being greatest in patients with dumping symptoms. Physiological concentrations of neurotensin have been shown to delay gastric emptying. The excessive rise in plasma neurotensin-like immunoreactivity in patients with dumping symptoms, presumably occuring as a result of the rapid passage of nutrients to the neurotensin-rich ileum, may possibly have a compensatory role in slowing further emptying from the stomach. 相似文献
67.
Background
Metabolically versatile soil bacteria Burkholderia cepacia complex (Bcc) have emerged as opportunistic pathogens, especially of cystic fibrosis (CF). Previously, we initiated the characterization of the phenylacetic acid (PA) degradation pathway in B. cenocepacia, a member of the Bcc, and demonstrated the necessity of a functional PA catabolic pathway for full virulence in Caenorhabditis elegans. In this study, we aimed to characterize regulatory elements and nutritional requirements that control the PA catabolic genes in B. cenocepacia K56-2. 相似文献68.
Hussien M Alwadie & Zakaria AM Baka 《Archives Of Phytopathology And Plant Protection》2013,46(3-4):195-209
A 12 month period survey of the fungi associated with Euphorbia inarticulata was evaluated. Sampling was concentrated mainly in Aseer region (South-West Saudi Arabia) and seven fungal species were identified as pathogens of this plant. Melampsora euphorbiae and Alternaria euphorbiicola were the most common species on this plant. Bipolaris euphorbiae, Botrytis ricini, Colletotrichum gloeosporioides, Oidium sp., Sphaceloma poinsettiase and Uromyces euphorbiae were less frequent species. These fungal pathogens were recorded for the first time on Euphorbia inarticulata in Saudi Arabia. Scanning and transmission electron microscopy revealed the colonization of M. euphorbiae, as an example, in leaf tissues of E. inarticulata. Remarkable ultrastructural changes in chloroplasts and nuclei of infected cells of E. inarticulata as a result of infection by M. euphorbiae were observed. 相似文献
69.
Afiniki B Zarafi AM Emechebe AD Akpa O Alabi 《Archives Of Phytopathology And Plant Protection》2013,46(1):11-17
The effect of various levels of nitrogen (0.0, 30.0, 60.0, 120.0) and phosphorus (0.0, 6.5, 13.0, 36.0) on the incidence and severity of downy mildew of pearl millet and yield of two pearl millet varieties (Zango and GB8375) were studied under field conditions in 2000 and 2001 respectively. Both nitrogen and phosphorus significantly increased incidence and severity of the disease in the two varieties. Grain yield and 1000 grain weight of the varieties also increased with nitrogen and phosphorus levels. 相似文献
70.
Molecular evidence for the rapid propagation of mouse t haplotypes from a single, recent, ancestral chromosome 总被引:11,自引:0,他引:11
Silver LM; Hammer M; Fox H; Garrels J; Bucan M; Herrmann B; Frischauf AM; Lehrach H; Winking H; Figueroa F 《Molecular biology and evolution》1987,4(5):473-482
Mouse t haplotypes are variant forms of chromosome 17 that exist at high
frequencies in worldwide populations of two species of commensal mice. To
determine both the relationship of t haplotypes to each other and the
species within which they exist, 35 representative t haplotypes were
analyzed by means of 10 independent molecular probes, including five DNA
clones and five polypeptide spots identified by means of two- dimensional
gel electrophoresis. All of the tested haplotypes were found to share
restriction fragments and polypeptide spots that are absent in mice
carrying wild-type forms of chromosome 17. This observation provides the
first direct evidence that all of the known t haplotypes are descendents of
a single ancestral chromosome. The absence of variation among t haplotypes
could mean that this ancestral chromosome existed relatively recently, in
which case it would be necessary to postulate introgressions of t
haplotypes across species lines to explain their presence in both Mus
domesticus and M. musculus. Alternatively, it is possible that the
ancestral chromosome existed prior to the split between M. domesticus and
M. musculus and that, by chance, our probes fail to detect polymorphisms
that exist among the t haplotypes. A further result of our analysis is the
characterization of a partial t haplotype in a wild population of Israeli
mice.
相似文献