Proteomic profile determination of autosomal aneuploidies by mass spectrometry on amniotic fluids

<p>Abstract</p> <p>Background</p> <p>Prenatal diagnosis of chromosomal abnormalities by cytogenetic analysis is time-consuming, expensive, and requires highly qualified technicians. Rapid diagnosis of aneuploidies followed by reassurance of women with normal results can be performed by molecular analysis of uncultured foetal cells. In the present study, we developed a proteomic fingerprinting approach coupled with a statistical classification method to improve diagnosis of aneuploidies, including trisomies 13, 18, and 21, in amniotic fluid samples.</p> <p>Results</p> <p>The proteomic spectra obtained from 52 pregnant women were compiled, normalized, and mass peaks with mass-to-charge ratios between 2.5 and 50 kDa identified. Peak information was combined together and analysed using univariate statistics. Among the 208 expressed protein peaks, 40 differed significantly between aneuploid and non aneuploid samples, with AUC diagnostic values ranging from 0.71 to 0.91. Hierarchical clustering, principal component analysis and support vector machine (SVM) analysis were performed. Two class predictor models were defined from the training set, which resulted in a prediction accuracy of 92.3% and 96.43%, respectively. Using an external and independent validation set, diagnostic accuracies were maintained at 87.5% and 91.67%, respectively.</p> <p>Conclusion</p> <p>This pilot study demonstrates the potential interest of protein expression signature in the identification of new potential biological markers that might be helpful for the rapid clinical management of high-risk pregnancies.</p

When Attribution of Consistency Depends on Group Value: Social Valorization of Preference for Consistency in Equivalent and Asymmetric Intergroup Relations

International audienceThe social valorization of Preference For Consistency (PFC) was examined via a minimal group paradigm activating either equivalent or asymmetric intergroup relations. After an aesthetic judgment task and assignment to one of two groups, participants (N = 298) completed the PFC scale according to three instructions: on their own behalf, as an ingroup member, or as an outgroup member (order counter-balanced). Results showed that in equivalent intergroup relations, participants attributed greater PFC to the ingroup and to the self than to the outgroup. In asymmetric intergroup relations, participants attributed greater PFC to the high-status group and to the self than to the low-status group, and this was independent of the participants’ group membership. We discuss the contribution the minimal group paradigm can make to revealing the social valorization of psychological constructs and the mechanisms underlying the social value accorded to PFC

Being hypocritical disturbs some people more than others: How individual differences in preference for consistency moderate the behavioral effects of the induced-hypocrisy paradigm

International audienceThis article examines if individual differences in preference for consistency affect the behavioral change in the induced-hypocrisy paradigm. Undergraduate students (N=108) completed the PFC scale either one month (no PFC-focus condition) or immediately before (PFC-focus condition) the induced-hypocrisy procedure; this procedure includes pro-socialadvocacy, transgression recall, and a behavioral change measure. Results demonstrated 1) that PFC-level predicts behavioral change only when the participants were focused on their own PFC, 2) a relationship between the number of recalled transgressions and behavioral change only for high-PFC participants in PFC-focus condition. The necessity of consideringsimultaneously PFC-level, PFC-focus and the number of recalled transgressions to better predict behavioral change in the hypocrisy-paradigm, is discusse

Autoanticorps et diagnostic précoce des cancers

Il est clairement établi que le système immunitaire réagit très précocement à l’apparition et au développement d’une masse tumorale. Cette réaction fait intervenir une réponse cellulaire (activation des lymphocytes T) mais aussi une réponse humorale (production d’anticorps) contre des autoantigènes tumoraux devenus fortement immunogènes. Durant ces dix dernières années, des méthodes de protéomique ont été développées afin d’identifier les autoanticorps circulants et les antigènes qui leur correspondent dans différents types de cancer. La détection dans le sérum des patients d’un panel d’autoanticorps dirigés contre des protéines tumorales a ainsi été proposée comme nouvelle stratégie diagnostique en cancérologie. Cette signature humorale semble tout particulièrement adaptée à la détection précoce des cancers, notamment ceux du sein et du poumon. Elle présente un grand intérêt pour les patients qui ont un risque élevé de développer des cancers comme par exemple les sujets tabagiques chroniques, et pour lesquels il y a un déficit d’examens complémentaires

Etude de la valeur sociale attribuée à la préférence de la consistance dans le cadre des relations intergroupes.

International audienceThe present research aims at exploring the social value of preference for consistency (PFC) in intergroup relations. In a first study (identification paradigm, N = 103), participants (students from University versus IUT – Institute of Technology) filled out the PFC scale on their own behalf, as an ingroup member and as an outgroup member (order counter-balanced). In the second study (judge paradigm, N = 219), participants were exposed to a high, low or moderate PFC target. First, they had to identify target’s group membership and then to attribute personality traits referring to social desirability and social utility dimensions to the target. Results show both an ingroup bias (IUT students) and an outgroup favoritism (University students) through attribution of consistency (Studies 1 and 2). Results also show that participants make more favorable judgments towards a high PFC target than towards a low or moderate PFC target, but solely on the social utility dimension (Study 2). Results are discussed in term of status primed with intergroup relationships and consistency attribution.Le présent article a pour objectif d’étudier la valeur sociale accordée à la préférence pour la consistance (PPC) par le biais des relations intergroupes. Lors d’une première étude (paradigme de l’identification, N = 103), les participants (étudiants de l’Université versus de l’IUT – Institut Universitaire de Technologie) remplissaient le questionnaire de consistance en leur nom propre, puis en s’identifiant à un membre de l’endogroupe et à un membre de l’exogroupe (ordre contrebalancé). Dans une deuxième étude (paradigme des juges, N = 219), les participants prenaient connaissance du portrait d’une cible à PPC forte, modérée, ou faible. Ils devaient ensuite se prononcer sur son appartenance groupale (endogroupe ou exogroupe) et lui attribuer des traits de personnalité en choisissant parmi les deux registres de la valeur, à savoir l’utilité sociale et la désirabilité sociale. Les résultats montrent un biais de favoritisme pro-endogroupe à travers l’attribution de consistance pour les étudiants de l’IUT et d’exofavoritisme pour ceux de l’Université (études 1 et 2). Ils mettent également en évidence que les cibles à forte PPC donnent lieu à une évaluation plus positive que les cibles à faible PPC et PPC modérée uniquement sur la dimension de l’utilité sociale (étude 2). Les résultats sont discutés en référence aux statuts activés dans les rapports intergroupes en lien avec l’attribution de consistance

When a refusal turns into donation: the moderating effect of the initial position toward blood donation in the door-in-the-face effectiveness

International audienceThis research aimed to test the moderating effect of people's initial position to blood donation on the actual acceptance to donate blood in a door-in-the-face situation. This position (attitude, self-importance, normative beliefs) was measured one month prior to the request (Study 1, N = 99) or immediately before (Study 2, N = 80). The results revealed that the doorin-the-face effect is moderated by the importance of blood donation to the self, all the more so when the position is made salient. This highlights the specific character of blood donation in France and the centrality of the importance of donating for the self at the heart of the DITF technique. These results offer new insights into the conditions that must be met to achieve acceptance to donate blood after an initial refusal

Improvement of protein immobilization for the elaboration of tumor-associated antigen microarrays: Application to the sensitive and specific detection of tumor markers from breast cancer sera

There is an urgent need to identify relevant tumor markers showing high sensitivity and specificity for early diagnosis and prognosis of breast cancer. Protein microarrays have demonstrated to be cost-effective, high through-put and powerful tools for screening and identifying tumor markers with only minute samples. Autoantibodies directed against tumor-associated antigens (TAAs) were shown to be relevant tumor markers. However, due to the variability of immune response from one individual to another and depending on the type of cancer, detection of only one type of anti-TAA autoantibody is not sufficient to give a reliable and precise diagnosis. It is necessary to use a set of several TAAs for determining specific autoimmune profiles. Therefore, combining various TAAs on different surfaces could improve sensitivity and specificity for anti-TAA autoantibody detection. Herein a panel of 10 proteins, including well-known tumor-associated antigens (TAAs) and potential new biomarkers of breast cancer, were immobilized onto microstructured microarray under optimized conditions (spotting pH buffer, surface chemistry, blocking procedure), in order to determine an autoimmune signature of breast cancer. Sera from 29 breast cancer patients and 28 healthy donors were screened in sandwich immunoassays on the miniaturized system to detect the eventual presence of anti-TAAs autoantibodies. Results indicated that the detection level of each anti-TAA autoantibody in a given serum sample was strongly dependant on the surface chemistry. Combining five TAAs (p53, Hsp60, Hsp70, Her2-Fc, NY-ESO-1) on two different surface chemistries (NHS and APDMES) allowed the significant detection of more than 82% breast cancer sera

Heat cluster map and principle component analysis (PCA) of aneuploidie amniotic fluid and normal samples

<p><b>Copyright information:</b></p><p>Taken from "Proteomic profile determination of autosomal aneuploidies by mass spectrometry on amniotic fluids"</p><p>http://www.proteomesci.com/content/6/1/1</p><p>Proteome Science 2008;6():1-1.</p><p>Published online 11 Jan 2008</p><p>PMCID:PMC2248173.</p><p></p> All 208 protein peaks from 2.5 to 50 kDa mass range and 3 different surface arrays were pooled to generate a heat cluster map (A) and PCA diagram (B). The PCA diagram illustrates the segregated samples based on normal (white circles) and aneuploidie (black circles) samples

Representative SELDI-TOF spectra (left panel) and gel (right panel) views of selected biomarkers obtained from normal and aneuploid AF samples

<p><b>Copyright information:</b></p><p>Taken from "Proteomic profile determination of autosomal aneuploidies by mass spectrometry on amniotic fluids"</p><p>http://www.proteomesci.com/content/6/1/1</p><p>Proteome Science 2008;6():1-1.</p><p>Published online 11 Jan 2008</p><p>PMCID:PMC2248173.</p><p></p> For both protein peaks, the data of three normal karyotypes samples (N, upper panel) and three aneuploidy karyotypes samples (A, lower panel) are shown. Frames indicate the positions of two peaks at 2876 and 3023 Da, respectively, both overexpressed in aneuploid samples. Overlay of protein mass spectra is represented in the upper box. Protein mass spectra obtained from aneuploid (red) and normal (blue) AF are superimposed