Specific age related signatures in Drosophila body parts transcriptome

BACKGROUND: During the last two decades progress in the genetics of aging in invertebrate models such as C. elegans and D. melanogaster has clearly demonstrated the existence of regulatory pathways that control the rate of aging in these organisms, such as the insulin-like pathway, the Jun kinase pathway and the Sir2 deacetylase pathway. Moreover, it was rapidly shown that some of these pathways are conserved from yeast to humans. In parallel to genetic studies, genomic expression approches have given us significant information on the gene expression modifications that occur during aging either in wild type or long-lived mutant animals. But most of the genomic studies of invertebrate models have been performed so far on whole animals, while several recent studies in mammals have shown that the effects of aging are tissue specific. RESULTS: We used oligonucleotide microarrays to address the specificities of transcriptional responses in aging Drosophila in head, thorax or whole body. These fly parts are enriched in transcripts that represent different and complementary sets of genes. We present evidence for both specific and common transcriptional responses during the aging process in these tissues. About half of the genes described as downregulated with age are linked to reproduction and enriched in gonads. Greater downregulation of mitochondrial genes, activation of the JNK pathway and upregulation of proteasome subunits in the thorax of aged flies all suggest that muscle may be particularly sensitive to aging. Simultaneous age-related impairment of synaptic transmission gene expression is observed in fly heads. In addition, a detailed comparison with other microarray data indicates that in aged flies there are significant deviations from the canonical responses to oxidative stress and immune stress. CONCLUSION: Our data demonstrates the advantages and value of regionalized and comparative analysis of gene expression in aging animals. Adding to the age-regulated genes already identified in whole animal studies, it provides lists of new regionalized genes to be studied for their functional role in the aging process. This work also emphasizes the need for such experiments to reveal in greater detail the consequences of the transcriptional modifications induced by aging regulatory pathways

Meteor and remote sensing satellites (a collection of articles)

Two short articles are presented that discuss satellite observation. Cloud cover interference of infrared photography is discussed. A file of the cloud cover over France is presented

Creating a magnetic resonance imaging ontology.

International audienceThe goal of this work is to build an ontology of Magnetic Resonance Imaging. The MRI domain has been analysed regarding MRI simulators and the DICOM standard. Tow MRI simulators have been analysed: JEMRIS, which is developed in XML and C++, has a hierarchical organisation and SIMRI, which is developed in C, has a good representation of MRI physical processes. To build the ontology we have used Protégé 4, owl2 that allows quantitative representations. The ontology has been validated by a reasoner (Fact++) and by a good representation of DICOM headers and of MRI processes. The MRI ontology would improved MRI simulators and eased semantic interoperability

Utilisation des ontologies dans le contexte de l'Imagerie par Résonance Magnétique

L imagerie médicale et en particulier l Imagerie par Résonance Magnétique (IRM) occupe une place de choix dans les décisions médicales. Malgré des techniques et des pratiques d examens comparables les industriels du secteur utilisent un vocabulaire différent pour décrire les événements de l expérience IRM. Les ontologies permettent de résoudre cette problématique. En les intégrant dans un système informatique nous avons choisi de proposer des solutions innovantes pour trois situations quotidiennes: l annotation d examen, la reconnaissance et la correction d artéfact et l aide à la prescription d examen. Les connaissances du domaine IRM sont issues de la littérature et de la pratique quotidienne. DICOM, élément incontournable à l échange de données en imagerie médicale, a été le point de départ de l élaboration de l ontologie. Les connaissances sur les artéfacts en IRM sont en partie issues d une collaboration avec l université de Texas A&M Temple. Pour l aide à la prescription d examen nous avons choisi une situation clinique représentative la demande d IRM dans le cadre des traumatismes du genou. Les statistiques proviennent d une étude réalisée dans le service de médecine du sport du CHU de Rennes. Les systèmes élaborés permettent aux utilisateurs d utiliser les ontologies sans y être confronté et permettent l analyse de l entête DICOM d une image, l annotation de l image, la comparaison d une image IRM pour la correction d artéfact et l aide à la prescription d IRM est sous la forme d un serveur web permettant à l utilisateur de connaître en fonction des signes cliniques présents, la probabilité d avoir une lésion lors de la réalisation de l IRM. Nous avons démontré la possibilité d utilisation des ontologies pour améliorer l exercice quotidien des praticiens. Les techniques utilisées montre la possibilité d utiliser les ontologies en les associant aux images et aux probabilités. Le système choisi, interface permettra l évolution vers une technologie de type webservice.Magnetic resonance imaging (MRI) is a key examination in medical decision making. Despite MRI technics are slightly similar, each industrial has developed his own vocabulary to describe the MRI experience. Ontologies have been developed to help in such situations. We have decided to create IT solutions using ontology for three daily radiological situations: exams annotation, MRI artifacts recognition and correction and exam appropriateness. The domain knowledge is extracted from literature and everyday practice. DICOM, as key element for data exchange in radiology, has been used to create the ontology. Concerning MRI artifacts, a part of the knowledge comes from a collaborative work with the university of Texas A&M Temple. Concerning exam appropriateness, we have chosen a representative clinical situation: interest of knee MRI in case of knee trauma. The statistical data are coming from a clinical study done in the CHU of Rennes. Our systems allow users to take benefits of ontology without facing it. They give a DICOM header analysis, proposed an image annotation, compare image to correct MRI artifacts and help physicians to judge MRI appropriateness in case of knee trauma. We have demonstrated that ontologies could be used to improve daily practice in radiology and that ontologies could be associated to image and statistical data. Future of this work could be a system transformation into a web service.RENNES1-Bibl. électronique (352382106) / SudocSudocFranceF

Lessons from the analysis of nonhuman primates for understanding human aging and neurodegenerative diseases

Animal models are necessary tools for solving the most serious challenges facing medical research. In aging and neurodegenerative disease studies, rodents occupy a place of choice. However, the most challenging questions about longevity, the complexity and functioning of brain networks or social intelligence can almost only be investigated in nonhuman primates. Beside the fact that their brain structure is much closer to that of humans, they develop highly complex cognitive strategies and they are visually-oriented like humans. For these reasons, they deserve consideration, although their management and care are more complicated and the related costs much higher. Despite these caveats, considerable scientific advances have been possible using nonhuman primates. This review concisely summarizes their role in the study of aging and of the mechanisms involved in neurodegenerative disorders associated mainly with cognitive dysfunctions (Alzheimer’s and prion diseases) or motor deficits (Parkinson’s and related diseases)

Rheumatoid arthritis seropositive for the rheumatoid factor is linked to the protein tyrosine phosphatase nonreceptor 22-620W allele

The protein tyrosine phosphatase nonreceptor type 22 (PTPN22) gene encodes for lymphoid tyrosine phosphatase LYP, involved in the negative regulation of early T-cell activation. An association has recently been reported between the PTPN22-620W functional allele and rheumatoid factor-positive (RF(+)) rheumatoid arthritis (RA), among other autoimmune diseases. Expected linkage proof for consistency cannot be definitely produced by an affected sib-pair (ASP) analysis. Our aim was therefore to search for linkage evidence with the transmission disequilibrium test. DNA from the French Caucasian population was available for two samples of 100 families with one RA patient and both parents, and for 88 RA index cases from RA ASP families. Genotyping was carried out by PCR-restriction fragment length polymorphism. The analysis was performed using the transmission disequilibrium test, genotype relative risk and ASP-based analysis. The transmission disequilibrium test of the PTPN22-620W allele revealed linkage and association for RF(+ )RA (61% of transmission, P = 0.037). The genotype relative risk showed the risk allele in 34% of RF(+ )RA patients and in 24% of controls derived from nontransmitted parental chromosomes (P = 0.047, odds ratio = 1.69, 95% confidence interval = 1.03–2.78). The ASP investigation showed no enriched risk allele in RA multiplex families, resulting in a lack of power of ASP analysis, explaining the published negative results. This study is the first to show linkage of PTPN22 to RF(+ )RA, consistent with PTPN22 as a new RA gene

Combining Gene Transfer and Nonhuman Primates to Better Understand and Treat Parkinson’s Disease

Parkinson's disease (PD) is a progressive CNS disorder that is primarily associated with impaired movement. PD develops over decades and is linked to the gradual loss of dopamine delivery to the striatum, via the loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc). While the administration of L-dopa and deep brain stimulation are potent therapies, their costs, side effects and gradual loss of efficacy underlines the need to develop other approaches. Unfortunately, the lack of pertinent animal models that reproduce DA neuron loss and behavior deficits-in a timeline that mimics PD progression-has hindered the identification of alternative therapies. A complementary approach to transgenic animals is the use of nonhuman primates (NHPs) combined with the overexpression of disease-related genes using viral vectors. This approach may induce phenotypes that are not influenced by developmental compensation mechanisms, and that take into account the personality of animals. In this review article, we discuss the combination of gene transfer and NHPs to develop "genetic" models of PD that are suitable for testing therapeutic approaches

Personal non-commercial use only

ABSTRACT. Objective. To investigate whether frequency of rheumatoid arthritis (RA) and/or other autoimmune (AI) disorders was increased in RA French Caucasian families among the first-(FDR) and seconddegree relatives (SDR), and to test whether the presence of AI disease family history identified a specific RA subset. Methods. We conducted telephone interviews to obtain histories of AI diseases among the FDR and SDR of 368 RA probands, belonging either to trio or affected sib-pair (ASP) families. All the AI diagnoses were confirmed by the physician of the affected relative

Chemometric perspectives on plankton community responses to natural iron fertilisation over and downstream of the Kerguelen Plateau in the Southern Ocean

International audienceWe examined phytoplankton community responses to natural iron fertilisation at 32 sites over and downstream from the Kerguelen Plateau in the Southern Ocean during the austral spring bloom in October–November 2011. The community structure was estimated from chemical and isotopic measurements (particulate organic carbon – POC; 13C-POC; particulate nitrogen – PN; 15N-PN; and biogenic silica – BSi) on size-fractionated samples from surface waters (300, 210, 50, 20, 5, and 1 μm fractions). Higher values of 13C-POC (vs. co-located 13C values for dissolved inorganic carbon – DIC) were taken as indicative of faster growth rates and higher values of 15N-PN (vs. co-located 15N-NO3 source values) as indicative of greater nitrate use (rather than ammonium use, i.e. higher f ratios).Community responses varied in relation to both regional circulation and the advance of the bloom. Iron-fertilised waters over the plateau developed dominance by very large diatoms (50–210 μm) with high BSi / POC ratios, high growth rates, and significant ammonium recycling (lower f ratios) as biomass built up. In contrast, downstream polar frontal waters with a similar or higher iron supply were dominated by smaller diatoms (20–50 μm) and exhibited greater ammonium recycling. Stations in a deep-water bathymetrically trapped recirculation south of the polar front with lower iron levels showed the large-cell dominance observed on the plateau but much less biomass. Comparison of these communities to surface water nitrate (and silicate) depletions as a proxy for export shows that the low-biomass recirculation feature had exported similar amounts of nitrogen to the high-biomass blooms over the plateau and north of the polar front. This suggests that early spring trophodynamic and export responses differed between regions with persistent low levels vs. intermittent high levels of iron fertilisation

Quantitative Comparison of Cone Beam Computed Tomography and Microradiography in the Evaluation of Bone Density after Maxillary Sinus Augmentation: A Preliminary Study

Purpose Cone beam computed tomography ( CBCT ) and microradiographic analyses were comparatively performed in maxillary sinus augmentation to preliminarily verify the diagnostic potential of CBCT on the evaluation of bone regeneration. Materials and Methods A two‐stage protocol was conducted in 19 consenting patients, all having the crestal bone ≤2 mm, in private dental office. Mineralized human bone allograft particles were used to augment sinus using lateral window approach. A succession of CBCT scans of the maxilla was taken before surgery, after sinus augmentation, and immediately after implant insertion. Using virtual probes, CBCT data were processed by medical imaging software and expressed as gray level ( GL ). A bone core biopsy was taken at implant placement, 6 months after surgery. Microradiography of transverse sections, taken 6, 8, and 10 mm from the crestal surface, of methacrylate‐embedded biopsies was performed to analyze and to evaluate the mineralized material amount ( MM %). Results A total of 21 sinus augmentations were performed. CBCT (mean GL : 646–693) data were not statistically different when comparing 6‐, 8‐, and 10‐mm sites to after grafting/implant‐insertion values. Furthermore, microradiographic (mean MM %: 45.3–48.3) data were not statistically different comparing 6‐, 8‐, and 10‐mm sites, due to variation of values among patients. A GL and MM % parallelism was identified considering each patient, instead. A significant correlation ( p  < .001) between GL and MM % was found after both W ilcoxon test for paired data and simple linear regression analysis. Conclusions The preliminary result clearly demonstrated the predictability of the CBCT analysis. Due to the limited sample and great variations of the MM % recorded in patients, further clinical and morphometric studies are needed to fulfill diagnostic expectations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108331/1/cid12016.pd