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41.
42.
Jean-Louis Spadoni Pierre Rucart Sigrid Le Clerc Dani?lle van Manen Cédric Coulonges Damien Ulveling Vincent Laville Taoufik Labib Lieng Taing Olivier Delaneau Matthieu Montes Hanneke Schuitemaker Josselin Noirel Jean-Fran?ois Zagury 《PloS one》2015,10(9)
Background
Many genome-wide association studies have been performed on progression towards the acquired immune deficiency syndrome (AIDS) and they mainly identified associations within the HLA loci. In this study, we demonstrate that the integration of biological information, namely gene expression data, can enhance the sensitivity of genetic studies to unravel new genetic associations relevant to AIDS.Methods
We collated the biological information compiled from three databases of expression quantitative trait loci (eQTLs) involved in cells of the immune system. We derived a list of single nucleotide polymorphisms (SNPs) that are functional in that they correlate with differential expression of genes in at least two of the databases. We tested the association of those SNPs with AIDS progression in two cohorts, GRIV and ACS. Tests on permuted phenotypes of the GRIV and ACS cohorts or on randomised sets of equivalent SNPs allowed us to assess the statistical robustness of this method and to estimate the true positive rate.Results
Eight genes were identified with high confidence (p = 0.001, rate of true positives 75%). Some of those genes had previously been linked with HIV infection. Notably, ENTPD4 belongs to the same family as CD39, whose expression has already been associated with AIDS progression; while DNAJB12 is part of the HSP90 pathway, which is involved in the control of HIV latency. Our study also drew our attention to lesser-known functions such as mitochondrial ribosomal proteins and a zinc finger protein, ZFP57, which could be central to the effectiveness of HIV infection. Interestingly, for six out of those eight genes, down-regulation is associated with non-progression, which makes them appealing targets to develop drugs against HIV. 相似文献43.
Martin Bencsik Yves Le Conte Maritza Reyes Maryline Pioz David Whittaker Didier Crauser Noa Simon Delso Michael I. Newton 《PloS one》2015,10(11)
Insect pollination is of great importance to crop production worldwide and honey bees are amongst its chief facilitators. Because of the decline of managed colonies, the use of sensor technology is growing in popularity and it is of interest to develop new methods which can more accurately and less invasively assess honey bee colony status. Our approach is to use accelerometers to measure vibrations in order to provide information on colony activity and development. The accelerometers provide amplitude and frequency information which is recorded every three minutes and analysed for night time only. Vibrational data were validated by comparison to visual inspection data, particularly the brood development. We show a strong correlation between vibrational amplitude data and the brood cycle in the vicinity of the sensor. We have further explored the minimum data that is required, when frequency information is also included, to accurately predict the current point in the brood cycle. Such a technique should enable beekeepers to reduce the frequency with which visual inspections are required, reducing the stress this places on the colony and saving the beekeeper time. 相似文献
44.
Maria Grazia Ammendolia Francesca Iosi Barbara De Berardis Giuliana Guccione Fabiana Superti Maria Pia Conte Catia Longhi 《PloS one》2014,9(1)
Listeria monocytogenes is the agent of listeriosis, a food-borne disease. It represents a serious problem for the food industry because of its environmental persistence mainly due to its ability to form biofilm on a variety of surfaces. Microrganisms attached on the surfaces are a potential source of contamination for environment and animals and humans. Titanium dioxide nanoparticles (TiO2 NPs) are used in food industry in a variety of products and it was reported that daily exposure to these nanomaterials is very high. Anti-listerial activity of TiO2 NPs was investigated only with UV-irradiated nanomaterials, based on generation of reactive oxigen species (ROS) with antibacterial effect after UV exposure. Since both Listeria monocytogenes and TiO2 NPs are veicolated with foods, this study explores the interaction between Listeria monocytogenes and non UV-irradiated TiO2 NPs, with special focus on biofilm formation and intestinal cell interaction. Scanning electron microscopy and quantitative measurements of biofilm mass indicate that NPs influence both production and structural architecture of listerial biofilm. Moreover, TiO2 NPs show to interfere with bacterial interaction to intestinal cells. Increased biofilm production due to TiO2 NPs exposure may favour bacterial survival in environment and its transmission to animal and human hosts. 相似文献
45.
46.
In this paper a new nanostructured support for the culture of cells is presented. The support consists of fields of sharp
and high-aspect-ratio nanoneedles. The support is obtained through a specifically developed process that allows controlling
the nanoneedles’s densities and height. The nanoneedles are typically 10 μm high with tip diameters under 200 nm. Cell viability
on this support was evaluated through long-term cells cultures. The narrow interface between the cells’ membrane and the nanoneedles
has been carefully observed to conclude on the perforation of the cells’ membrane thanks to the sharp nanoneedles. Such a
nanostructured chip, allowing specific interaction, opens the door to a large number of exciting and valuable applications
such as nanoporation for transfection or internal cell potential recording. 相似文献
47.
48.
Matthieu Guillemain Romain Blanc Christelle Lucas Michel Lepley 《Biodiversity and Conservation》2007,16(12):3633-3651
Ecotourism is becoming very popular, especially in protected areas where wildlife concentrate and is easier to observe, but
the consequences of associated disturbance have seldom be quantified other than in the short-term, making the sustainability
of this activity untested. We combined a historical, an empirical and an experimental approach to assess the long-, medium-
and short-term consequences of disturbance to wintering wildfowl (Anatidae) in a wetland of international importance in the Camargue, Southern France. In the short-term, disturbance made teal (Anas crecca) move away temporarily from observation blinds without leaving the waterbody. Wildfowl fed more after disturbance, disrupting
their normal resting activities. In the medium-term, waterbodies with more tourists did not host fewer birds: conversely the
most heavily disturbed one hosted the highest wildfowl density. In the long term, wildfowl numbers were not related with the
number of visitors. When practiced with appropriate guiding of people, and where appropriate facilities are provided to limit
human disturbance as done here, ecotourism may not affect wintering wildfowl other than reversibly in the very short term.
The legitimate demand of the public for access, even in fragile protected areas, may therefore be sustainable under some conditions. 相似文献
49.
Animal serum-free culture conditions for isolation and expansion of multipotent mesenchymal stromal cells from human BM 总被引:4,自引:0,他引:4
Müller I Kordowich S Holzwarth C Spano C Isensee G Staiber A Viebahn S Gieseke F Langer H Gawaz MP Horwitz EM Conte P Handgretinger R Dominici M 《Cytotherapy》2006,8(5):437-444
BACKGROUND: Multipotent mesenchymal stromal cells (MSC) have become important tools in regenerative and transplantation medicine. Rapidly increasing numbers of patients are receiving in vitro-expanded MSC. Culture conditions typically include FSC because human serum does not fully support growth of human MSC in vitro (MSC(FCS)). Concerns regarding BSE, other infectious complications and host immune reactions have fueled investigation of alternative culture supplements. METHODS: As PDGF has long been identified as a growth factor for MSC, we tested media supplementation with platelet lysate for support of MSC proliferation. RESULTS: We found that primary cultures of BM-derived MSC can be established with animal serum-free media containing fresh frozen plasma and platelets (MSC(FFPP)). Moreover, MSC(FFPP) showed vigorous proliferation that was superior to classical culture conditions containing FCS. MSC(FFPP) morphology was equivalent to MSC(FCS), and MSC(FFPP) expressed CD73, CD90, CD105, CD106, CD146 and HLA-ABC while being negative for CD34, CD45 and surface HLA-DR, as expected. In addition to being phenotypically identical, MSC(FFPP) could efficiently differentiate into adipocytes and osteoblasts. In terms of immune regulatory properties, MSC(FFPP) were indistinguishable from MSC(FCS). Proliferation of PBMC induced by IL-2 in combination with OKT-3 or by PHA was inhibited in the presence of MSC(FFPP). DISCUSSION: Taken together, FCS can be replaced safely by FFPP in cultures of MSC for clinical purposes. 相似文献
50.
Franck Desmoulin Michel Galinier Charlotte Trouillet Matthieu Berry Clément Delmas Annie Turkieh Pierre Massabuau Heinrich Taegtmeyer Fatima Smih Philippe Rouet 《PloS one》2013,8(4)