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161.
Pietro Martini Loïc Costeur Jean-Marie Le Tensorer Peter Schmid 《L'Anthropologie》2015,119(5):687-693
The family Camelidae has been present in Eurasia since the latest Miocene, and several species are recognized, but their evolution is poorly known. The region of El Kowm, central Syria, includes several sites spanning the Early to Late Pleistocene and provides the only abundant fossil record of camelids in the Middle East. Our preliminary results show that several species are present over the sequence, revealing some surprising evolutionary trends. 相似文献
162.
Influence of native and alien Prunus species and light conditions on performance of the leaf beetle Gonioctena quinquepunctata
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Ewa Mąderek Adrian Łukowski Marian J. Giertych Piotr Karolewski 《Entomologia Experimentalis et Applicata》2015,155(3):193-205
The polyphagous beetle Gonioctena quinquepunctata Fabricius (Coleoptera: Chrysomelidae) is a serious leaf pest of the native European bird cherry, Prunus padus L., and the invasive alien black cherry, Prunus serotina Ehrh. (Rosaceae). In the shade, leaf damage is extensive in both species, whereas in full light, it is extensive in P. padus, but very low in P. serotina. We determined the influence of Prunus species and light conditions on differences in performance of both sexes of this folivore. In a laboratory experiment in which larvae were fed with leaves of a single species grown under particular light conditions, we measured larval, pupal, and adult mass, efficiency of conversion of ingested food (ECI), duration of development, total food eaten, and relative growth rate. In the field, we observed differences in beetle mass on shrubs of the two species growing under various light conditions. From the field observations, we hypothesised that leaves of the invasive P. serotina are not an equally good food source as leaves of P. padus for G. quinquepunctata, and the preference of these beetles for shaded shrubs is most favourable for their growth and development. Under laboratory conditions, we found that the beetle growth rate was not affected significantly by Prunus species or light conditions, despite the significant effect of light condition on the structure and chemical composition of Prunus seedlings. The lower ECI value for larvae feeding on sunlit leaves was compensated for by their higher level of consumption. In the field, adult insect mass was higher on P. padus than on P. serotina, and higher on sunlit shrubs of both species than on shaded ones. Under natural conditions, the mass of adult insects is probably also affected by other factors, such as predators and competition among folivores. 相似文献
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165.
Evidence of a link between demographic rates and species habitat suitability from post release movements in a reinforced bird population
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Anne‐Christine Monnet Loïc A. Hardouin Alexandre Robert Yves Hingrat Frédéric Jiguet 《Oikos》2015,124(8):1089-1097
Despite the increasing use of species distribution models for predicting current or future animal distribution, only a few studies have linked the gradient of habitat suitability (HS) to demographic parameters. While such approaches can improve the reliability of models, they can help to better predict the response of species to changes in HS over space and time, as induced by ongoing global change. Here, we tested whether the spatial variation in HS along the individual movement path is related to survival, using extensive tracking data collected from captive‐bred individuals translocated to reinforce the wild populations of houbara bustard. We first modelled and mapped the HS from presence data of wild individuals using niche models in a consensus framework. We further analysed survival of released individuals using capture–recapture modelling and its links to HS, as the trend in suitability from the release sites along movements. We found that the survival of released individuals was related to changes in HS along their movements. For instance, individuals which moved to sites of lower HS than their release sites have lower survival probabilities than the others, independently of the HS of the release sites and daily movement rate. Our results provide an empirical support of the relationship between HS and survival, a major fitness component. 相似文献
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Guillaume Marcion Renaud Seigneuric Evelyne Chavanne Yves Artur Lo?c Briand Tarik Hadi Jessica Gobbo Carmen Garrido Fabrice Neiers 《Cell stress & chaperones》2015,20(1):61-72
The human inducible heat shock protein 70 (hHsp70), which is involved in several major pathologies, including neurodegenerative disorders and cancer, is a key molecular chaperone and contributes to the proper protein folding and maintenance of a large number of protein structures. Despite its role in disease, the current structural knowledge of hHsp70 is almost exclusively based on its Escherichia coli homolog, DnaK, even though these two proteins only share ~50 % amino acid identity. For the first time, we describe a complete heterologous production and purification strategy that allowed us to obtain a large amount of soluble, full-length, and non-tagged hHsp70. The protein displayed both an ATPase and a refolding activity when combined to the human Hsp40. Multi-angle light scattering and bio-layer interferometry analyses demonstrated the ability of hHsp70 to homodimerize. The role of the C-terminal part of hHsp70 was identified and confirmed by a study of a truncated version of hHsp70 that could neither dimerize nor present refolding activity.
Electronic supplementary material
The online version of this article (doi:10.1007/s12192-014-0526-3) contains supplementary material, which is available to authorized users. 相似文献168.
Thomas?Durand Sophie?Jacob Laura?Lebouil Hassen?Douzane Philippe?Lestaevel Amithys?Rahimian Dimitri?Psimaras Lo?c?Feuvret Delphine?Leclercq Bruno?Brochet Radia?Tamarat Fabien?Milliat Marc?Benderitter Nicolas?Vayatis Georges?No?l Khê?Hoang-Xuan Jean-Yves?Delattre Damien?Ricard Marie-Odile?BernierEmail author 《BMC neurology》2015,15(1):261
Background
Radiotherapy is one of the most important treatments of primary and metastatic brain tumors. Unfortunately, it can involve moderate to severe complications among which leukoencephalopathy is very frequent and implies cognitive deficits such as memory, attention and executive dysfunctions. However, the incidence of this complication is not well established and the risk factors and process are poorly understood. The main objective of the study is to improve knowledge on radio-induced leukoencephalopathy based on pluridisciplinar approaches combining cognitive, biologic, imagery and dosimetric investigations.Method/Design
The EpiBrainRad study is a prospective cohort study including newly diagnosed high grade gliomas patients treated by radiotherapy and concomitant-adjuvant temozolomide chemotherapy. Patients are included between their surgery and first day of radio-chemotherapy, and the follow-up lasts for 3 years after treatment. Cognitive functioning assessments, specific blood biomarkers measures and magnetic resonance imagery are performed at different moment during the follow-up, and a specific dosimetric assessment of organs involved in the beam fields is performed. Firstly, leukoencephalopathy incidence rate will be estimated in this population. Secondly, correlations between cognitive impairments and dosimetry, biomarkers ranges and anomalies on imagery will be analyzed in order to better understand the onset and evolution of cognitive decrement associated with radiotherapy. Furthermore, a new cognitive test, quickly and easily performed, will be studied to determine its sensibility to detect leukoencephalopathy decrement.Discussion
With an original multidisciplinary approach, the EpiBrainRad study aims to improve knowledge on radio-induced leukoencephalopathy in order to improve its early diagnosis and prevention. The main challenge is to preserve quality-of-life after cancer treatments which imply to study the incidence of radiation-induced complications and their associated risk factors.Trial Registration
NCT02544178169.
Manfredi P Renzi F Mally M Sauteur L Schmaler M Moes S Jenö P Cornelis GR 《Molecular microbiology》2011,81(4):1050-1060
Capnocytophaga canimorsus are commensal Gram-negative bacteria from dog's mouth that cause rare but dramatic septicaemia in humans. C. canimorsus have the unusual property to feed on cultured mammalian cells, including phagocytes, by harvesting the glycan moiety of cellular glycoproteins. To understand the mechanism behind this unusual property, the genome of strain Cc5 was sequenced and analysed. In addition, Cc5 bacteria were cultivated onto HEK 293 cells and the surface proteome was determined. The genome was found to encode many lipoproteins encoded within 13 polysaccharide utilization loci (PULs) typical of the Flavobacteria-Bacteroides group. PULs encode surface exposed feeding complexes resembling the archetypal starch utilization system (Sus). The products of at least nine PULs were detected among the surface proteome and eight of them represented more than half of the total peptides detected from the surface proteome. Systematic deletions of the 13 PULs revealed that half of these Sus-like complexes contributed to growth on animal cells. The complex encoded by PUL5, one of the most abundant ones, was involved in foraging glycans from glycoproteins. It was essential for growth on cells and contributed to survival in mice. It thus represents a fitness factor during infection. 相似文献
170.
Lekka M Gil D Dąbroś W Jaczewska J Kulik AJ Lekki J Stachura Z Stachura J Laidler P 《Journal of molecular recognition : JMR》2011,24(5):833-842
The expression of N‐cadherin, characteristic of various cancers, very often leads to changes in the cells' adhesive properties. Thus, we sought to find out if N‐cadherin expressed in various, but cancer‐related cells, differs in its functional properties that could contribute to variations in cells' phenotypes. In our work, measurements of an unbinding force of a single N‐cadherin molecule, probed with the same antibody both on a surface of living non‐malignant (HCV29) and malignant cells (T24) of bladder cancer, were carried out with the use of an atomic force microscopy. The results show the enhanced N‐cadherin level in T24 malignant cells (8.7% vs. 3.6% obtained for non‐malignant one), confirmed by the Western blot and the immunohistochemical staining. The effect was accompanied by changes in unbinding properties of an individual N‐cadherin molecule. Lower unbinding force values (26.1 ± 7.1 pN) in non‐malignant cells reveal less stable N‐cadherin complexes, as compared to malignant cells (61.7 ± 14.6 pN). This suggests the cancer‐related changes in a structure of the binding site of the antibody, located at the extracellular domain of N‐cadherin. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献