iGEM REPORT: Gotta Detect ‘Em All: a multi-STI sensor based on aptamers

/International audienceNowadays, STIs constitute a major public health issue. Indeed, treatments are often started too late because of belated diagnosis resulting in health problems, such as sterility. If prevention is probably the most effective action one can take to prevent the spread of STIs, early detection could help limit their deleterious effects. In this work, a new diagnosis approach based on aptamers is presented. Bound to paper, they allow the detection of HIV and Hepatitis B biomarkers from a blood sample. The associated device is composed of an anchor, the streptavidin protein, allowing the fixation of the aptamer to the paper via biotin (see graphical abstract). With this system, the HIV-1 Reverse Transcriptase (BBa_K1934060 and BBa_K1934061: protein subunits p51 and p66) and HBsAg (surface antigen of Hepatitis B) are specifically targeted. Then, the biomarker/aptamer complex is detected by two methods. The first one is based on fluorescence. As a proof of concept, a paired ATP/aptamer was used and enabled to successfully detect ATP up to 10 µmol.L-1. However, the signal was not detectable with naked eyes or with a cell phone equipped with blue and green filters either. Therefore, a lateral flow assay with nano-sized latex black beads was tested. This second technique showed that a protein biomarker, such as thrombin, could be complexed with latex beads coated with aptamers, in liquid. Finally, the ultimate step, migration of the latex beads inside paper, needs further optimization. Moreover, to easily handle several STI-tests on a single paper strip, an innovative bio-sourced PLA casing was designed and 3D printed to offer an additional intuitive user-interface

iGEM REPORT: Gotta Detect ‘Em All: a multi-STI sensor based on aptamers

/International audienceNowadays, STIs constitute a major public health issue. Indeed, treatments are often started too late because of belated diagnosis resulting in health problems, such as sterility. If prevention is probably the most effective action one can take to prevent the spread of STIs, early detection could help limit their deleterious effects. In this work, a new diagnosis approach based on aptamers is presented. Bound to paper, they allow the detection of HIV and Hepatitis B biomarkers from a blood sample. The associated device is composed of an anchor, the streptavidin protein, allowing the fixation of the aptamer to the paper via biotin (see graphical abstract). With this system, the HIV-1 Reverse Transcriptase (BBa_K1934060 and BBa_K1934061: protein subunits p51 and p66) and HBsAg (surface antigen of Hepatitis B) are specifically targeted. Then, the biomarker/aptamer complex is detected by two methods. The first one is based on fluorescence. As a proof of concept, a paired ATP/aptamer was used and enabled to successfully detect ATP up to 10 µmol.L-1. However, the signal was not detectable with naked eyes or with a cell phone equipped with blue and green filters either. Therefore, a lateral flow assay with nano-sized latex black beads was tested. This second technique showed that a protein biomarker, such as thrombin, could be complexed with latex beads coated with aptamers, in liquid. Finally, the ultimate step, migration of the latex beads inside paper, needs further optimization. Moreover, to easily handle several STI-tests on a single paper strip, an innovative bio-sourced PLA casing was designed and 3D printed to offer an additional intuitive user-interface

iGEM REPORT: Gotta Detect ‘Em All: a multi-STI sensor based on aptamers

/International audienceNowadays, STIs constitute a major public health issue. Indeed, treatments are often started too late because of belated diagnosis resulting in health problems, such as sterility. If prevention is probably the most effective action one can take to prevent the spread of STIs, early detection could help limit their deleterious effects. In this work, a new diagnosis approach based on aptamers is presented. Bound to paper, they allow the detection of HIV and Hepatitis B biomarkers from a blood sample. The associated device is composed of an anchor, the streptavidin protein, allowing the fixation of the aptamer to the paper via biotin (see graphical abstract). With this system, the HIV-1 Reverse Transcriptase (BBa_K1934060 and BBa_K1934061: protein subunits p51 and p66) and HBsAg (surface antigen of Hepatitis B) are specifically targeted. Then, the biomarker/aptamer complex is detected by two methods. The first one is based on fluorescence. As a proof of concept, a paired ATP/aptamer was used and enabled to successfully detect ATP up to 10 µmol.L-1. However, the signal was not detectable with naked eyes or with a cell phone equipped with blue and green filters either. Therefore, a lateral flow assay with nano-sized latex black beads was tested. This second technique showed that a protein biomarker, such as thrombin, could be complexed with latex beads coated with aptamers, in liquid. Finally, the ultimate step, migration of the latex beads inside paper, needs further optimization. Moreover, to easily handle several STI-tests on a single paper strip, an innovative bio-sourced PLA casing was designed and 3D printed to offer an additional intuitive user-interface

La rumeur au Moyen Âge

Fausses nouvelles de la mort du roi, révélations de complots contre la chrétienté, dénonciations des mœurs légères des reines et princesses, accusations de crimes sexuels contre des ecclésiastiques, multiplications de miracles autour de tombes, portraits flatteurs ou infamants de grands et de petits que rien ne vérifie en dehors d’affirmations transmises à l’oral comme à l’écrit, entre voisins, amis, courtisans, guerriers et hommes d’Église : la rumeur est omniprésente au Moyen Âge. Elle n’épargne aucun pan de la société, aucun groupe humain et elle est de tous les temps entre le Ve et le XVe siècle. Elle s’inscrit dans les sources textuelles de toute sorte, qui lui répondent, la confortent, la relaient ou simplement la disent avec des mots bien spécifiques. Pourtant, les médiévistes ont souvent considéré qu’ils ne pouvaient saisir dans la documentation plus que le souvenir de la rumeur. Sujet à la mode, la rumeur médiévale a principalement été étudiée, jusqu’ici, dans le cadre des rapports entretenus entre le peuple et les autorités à la fin du Moyen Âge. Envisagée sur le fond des grandes crises (guerres, révoltes), associée au défaut d’information et à la sédition, jugée caractéristique et révélatrice de l’opinion des gens de peu en rupture momentanée avec les gouvernants, la rumeur a rarement été abordée comme un phénomène de communication entre égaux (chez les élites comme chez les humbles), dans des usages socialement constructifs et révélateurs de craintes, mais aussi de revendications, d’espoirs, d’imaginaires et de croyances. C’est pour tenter de renouveler et de compléter cette approche historique, que les auteurs du présent ouvrage ont croisé les résultats de recherches menées sur le statut, la construction, les usages et la portée d’une rumeur qui n’est, au Moyen Âge, caractéristique d’aucun groupe social, économique, politique ou d’opinion spécifique. Le mépris affiché par les élites à son égard, lorsqu’elle émane des petits et de leurs ennemis, ne suffit pas à faire oublier que la rumeur est avant tout un moyen de fédérer