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81.
Benedikt Junglas Stefan T. Huber Thomas Heidler Lukas Schlösser Daniel Mann Raoul Hennig Mairi Clarke Nadja Hellmann Dirk Schneider Carsten Sachse 《Cell》2021,184(14):3674-3688.e18
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82.
Inositol trisphosphate is known to mobilize calcium from internal stores in plant cells. However, with the exception of the vacuole, the largest plant cell compartment, organelles responsive to inositol trisphosphate have not been extensively identified. In this way, we have separated membrane vesicles from the same carrot microsomal fraction and identified them, both by marker enzyme activities and electron microscopy. These correspond to pure plasma membrane, pure tonoplast and mixed mitochondria, endoplasmic reticulum, Golgi membrane fractions. All the fractions accumulated calcium in a ATP-dependent manner and were tightly sealed. Inositol trisphosphate-dependent calcium releases were accurately measured only in fractions corresponding functionally and structurally to tonoplast, the vacuolar membrane. The process was dose-dependent and fairly specific for inositol trisphosphate. While highly significant, approximately 40% of the mobile calcium only may be released from tonoplast vesicles by inositol trisphosphate which remained basically intact during the release experiments. From these results it is concluded that the vacuole is the richest store of calcium directly mobilizable by inositol trisphosphate in plant cells, but inositol trisphosphate is not able to release the overall mobile vacuolar calcium. 相似文献
83.
Both the acoustic variability of a distractor sequence and the degree to which it violates expectations are important determinants of auditory distraction. In four experiments we examined the relative contribution of local auditory changes on the one hand and expectation violations on the other hand in the disruption of serial recall by irrelevant sound. We present evidence for a greater disruption by auditory sequences ending in unexpected steady state distractor repetitions compared to auditory sequences with expected changing state endings even though the former contained fewer local changes. This effect was demonstrated with piano melodies (Experiment 1) and speech distractors (Experiment 2). Furthermore, it was replicated when the expectation violation occurred after the encoding of the target items (Experiment 3), indicating that the items'' maintenance in short-term memory was disrupted by attentional capture and not their encoding. This seems to be primarily due to the violation of a model of the specific auditory distractor sequences because the effect vanishes and even reverses when the experiment provides no opportunity to build up a specific neural model about the distractor sequence (Experiment 4). Nevertheless, the violation of abstract long-term knowledge about auditory regularities seems to cause a small and transient capture effect: Disruption decreased markedly over the course of the experiments indicating that participants habituated to the unexpected distractor repetitions across trials. The overall pattern of results adds to the growing literature that the degree to which auditory distractors violate situation-specific expectations is a more important determinant of auditory distraction than the degree to which a distractor sequence contains local auditory changes. 相似文献
84.
Asher Bashiri Katherine Ida Halper Raoul Orvieto 《Reproductive biology and endocrinology : RB&E》2018,16(1):121
Recurrent implantation failure (RIF) refers to cases in which women have had three failed in vitro fertilization (IVF) attempts with good quality embryos. The definition should also take advanced maternal age and embryo stage into consideration. The failure of embryo implantation can be a consequence of uterine, male, or embryo factors, or the specific type of IVF protocol. These cases should be investigated to determine the most likely etiologies of the condition, as this is a complex problem with several variables. There are multiple risk factors for recurrent implantation failure including advanced maternal age, smoking status of both parents, elevated body mass index, and stress levels. Immunological factors such as cytokine levels and presence of specific autoantibodies should be examined, as well as any infectious organisms in the uterus leading to chronic endometritis. Uterine pathologies such as polyps and myomas as well as congenital anatomical anomalies should be ruled out. Sperm analysis, pre-implantation genetic screening and endometrial receptivity should be considered and evaluated, and IVF protocols should be tailored to specific patients or patient populations. Treatment approaches should be directed toward individual patient cases. In addition, we suggest considering a new initial step in approach to patients with RIF, individualized planned activities to activate the brain's reward system in attempt to improve immunological balance in the body. 相似文献
85.
Michele?Cesari Lara?Maistrello Lucia?Piemontese Raoul?Bonini Paride?Dioli Wonhoon?Lee Chang-Gyu?Park Georgios?K.?Partsinevelos Lorena?Rebecchi Roberto?GuidettiEmail authorView authors OrcID profile 《Biological invasions》2018,20(4):1073-1092
Halyomorpha halys is an invasive stink bug pest originating from East Asia. In Europe, it was first detected in Switzerland in 2004. It is now present in thirteen countries, and seems to be spreading throughout the continent. In Italy, where it has been recorded since 2012, other than being an urban nuisance, it is causing severe damage in commercial fruit orchards. An integrated approach, using current and previous observational data in space and time and molecular information, was used to identify the genetic diversity of this pest in Europe, its invasion history, and the potential pathways of entry and diffusion. The analysis of 1175 bp of mitochondrial DNA cytochrome c oxidase I and II genes (cox1, cox2) led to the identification of twenty previously unknown haplotypes. The European distribution of H. halys is the result of multiple invasions that are still in progress, and, in some cases, it was possible to identify the specific Asian areas of origin. Moreover, secondary invasions could have occurred among European countries by a bridgehead effect. In Italy, the data were more clearly related to their temporal occurrence, allowing for a clearer reading of the patterns of invasion and dispersion. After having successfully established in localized areas, H. halys further expanded its range by an active dispersion process and/or by jump dispersal events due to passive transport. The multiple introductions from different areas of the native range together with the different patterns of diffusion of H. halys, may hamper the pest management strategies for its containment. 相似文献
86.
Kevin Mouzat Nicolas Molinari Jovana Kantar Anne Polge Philippe Corcia Philippe Couratier Pierre Clavelou Raul Juntas-Morales Nicolas Pageot Jean -Marc A. Lobaccaro Cedric Raoul Serge Lumbroso William Camu 《Molecular neurobiology》2018,55(3):1959-1965
Amyotrophic lateral sclerosis (ALS) is one of the most severe motor neuron (MN) disorders in adults. Phenotype of ALS patients is highly variable and may be influenced by modulators of energy metabolism. Recent works have implicated the liver X receptors α and β (LXRs), either in the propagation process of ALS or in the maintenance of MN survival. LXRs are nuclear receptors activated by oxysterols, modulating cholesterol levels, a suspected modulator of ALS severity. In a cohort of 438 ALS patients and 330 healthy controls, the influence of LXR genes on ALS risk and phenotype was studied using single nucleotide polymorphisms (SNPs). The two LXRα SNPs rs2279238 and rs7120118 were shown to be associated with age at onset in ALS patients. Consistently, homozygotes were twice more correlated than were heterozygotes to delayed onset. The onset was thus delayed by 3.9 years for rs2279238 C/T carriers and 7.8 years for T/T carriers. Similar results were obtained for rs7120118 (+2.1 years and +6.7 years for T/C and C/C genotypes, respectively). The LXRβ SNP rs2695121 was also shown to be associated with a 30% increase of ALS duration (p = 0.0055, FDR = 0.044). The tested genotypes were not associated with ALS risk. These findings add further evidence to the suspected implication of LXR genes in the disease process of ALS and might open new perspectives in ALS therapeutics. 相似文献
87.
Suele Aparecida Mendes Santos Thiago Rodrigues dos Santos Mariana S. R. Furtado Raoul Henry Carla Ferragut 《Limnology》2018,19(2):209-218
Periphyton plays an important functional role in the retention of nutrients in aquatic ecosystems, especially phosphorus. We evaluated the effects of enrichment with N and P and the effect after 20 days of no additional N and P on periphyton on artificial substratum in open-bottom mesocosms. The aim was to jointly evaluate periphyton, phytoplankton and zooplankton in the presence of macrophytes. Experimental conditions simulated natural conditions and nutrient addition was based on the maximum concentration recorded in mesotrophic reservoir. Our hypothesis is that the periphyton is sensitive to the effects of N and P enrichment and its interruption, despite the positive response of phytoplankton and zooplankton. Two treatments were designed using open-bottom mesocosms (n = 3): control (no nutrient addition); NP+ (combined phosphorus and nitrogen addition). Sampling for the measurement of biotic and abiotic variables was performed, with 10 days of continuous enrichment, on the 3rd, 6th and 11th, and 20 days after enrichment had ended (31st day). Periphyton chlorophyll a, dry mass and algal density increased significantly with the addition of N and P and decreased 20 days after the interruption of the enrichment. The highest periphyton P content was found in the NP+ treatment. The enrichment had a positive effect on Chrysophyceae (Chromulina spp.) and rotifer (Polyarthra spp.) density and the interruption of enrichment favored Bacillariophyceae (Gomphonema sp.) and rotifers (Gastropus stylifer). Phytoplankton responded positively to enrichment. Along with the high macrophyte coverage over the experimental period, we evidenced the positive effect enrichment had on phytoplankton biomass and zooplankton abundance. Therefore, periphyton on artificial substrate was sensitive to effects of N and P enrichment and its interruption, responding promptly to changes in nutrient availability in a scenario of high competition and grazing. 相似文献
88.
Neutrophils differentially attenuate immune response to Aspergillus infection through complement receptor 3 and induction of myeloperoxidase
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89.
90.
Effects of habitat fragmentation on provisioning rates, diet and breeding success in two species of tit (great tit and blue tit) 总被引:2,自引:0,他引:2
Nadia Nour David Currie Erik Matthysen Raoul Van Damme André A. Dhondt 《Oecologia》1998,114(4):522-530
The aim of this study was to examine the effects of forest fragmentation on the ability of parent birds to provide their
young with an adequate food supply. To examine whether prey population densities of the great tit (Parus major L.) and the blue tit (P. caeruleus L.) vary between study areas in different forest size classes we compared provisioning rates and chick diet and related these
parameters to breeding success. We filmed 217 nests over two breeding seasons and collected data on frass fall as a general
estimate of caterpillar availability. Nests which were attended by none or one parent only during filming (n = 46) were excluded from the analyses. In both years and for both species feeding rates were highest in the smallest fragments
and lowest in the large forest. There was also a suggestion that differences in feeding rates between areas vary between years.
We found no consistent tendency for prey size to change with forest size, although both species brought slightly smaller prey
items to the nest in the smallest forest fragments and feeding rates correlated negatively with prey size. Caterpillars were
the main item fed to nestlings, in both species. We found no evidence to suggest that either frass fall or the proportion
of caterpillars in the diet varied with forest size. There was also no correlation between mean frass fall and the total number
of caterpillars brought to the nests, in either species. Breeding success, as measured by clutch size, brood size, fledging
weight and fledging success, did not differ between the small fragments and the large forest, in either species. There was
also no relationship between provisioning rate (as concerns volume of prey fed to nestlings and the quality of chick diet)
and breeding success parameters. In conclusion, this study does not suggest suboptimal foraging or breeding conditions in
small fragments compared to a nearby large forest, for either species.
Received: 23 June 1997 / Accepted: 29 December 1997 相似文献