A novel blueprint for "top down" differentiation defines the cervical squamocolumnar junction during development, reproductive life and neoplasia.

in Journal of Pathology (The) (2013), 229(3), 460-8

The cervical squamocolumnar (SC) junction is the site of a recently discovered "embryonic" cell population that was proposed as the cell of origin for cervical cancer and its precursors. How this ... [more ▼]

The cervical squamocolumnar (SC) junction is the site of a recently discovered "embryonic" cell population that was proposed as the cell of origin for cervical cancer and its precursors. How this population participates in cervical remodeling and neoplasia is unclear. In the present study, we analyzed the SC junction immunophenotype during pre and postnatal human and mouse development and in the adult, processes of metaplastic evolution of SC junction, microglandular change and early cervical neoplasia. Early in life, embryonic cervical epithelial cells were seen throughout the cervix and subsequently diminished in number to become concentrated at the SC junction in the adult. In all settings, there was a repetitive scenario in which cuboidal embryonic/SC junction cells gave rise to subjacent metaplastic basal/reserve cells with a switch from the SC junction positive to negative immunophenotype. This downward or basal (rather than upward or apical) evolution from progenitor cell to metaplastic progeny was termed reverse or "top down" differentiation. A similar pattern was noted in high grade squamous intraepithelial lesions (HSIL), suggesting HPV infection of the cuboidal SC junction cells initiated outgrowth of basally-oriented neoplastic progeny. The progressive loss of the embryonic/SC junction markers occurred with top-down differentiation during development, remodeling and early neoplasia. Interestingly, most low grade SILs were SC junction negative, implying infection of metaplastic progeny rather than the original SC junction cells. This proposed model of "top down" differentiation resolves the mystery of how SC junction cells both remodel the cervix and participate in neoplasia and provides for a second population of metaplastic progeny (including basal and reserve cells), the infection of which is paradoxically less likely to produce a biologically aggressive precursor. It also provides new targets in animal models to determine why the SC junction is uniquely susceptible to carcinogenic HPV infection. Copyright (c) 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [less ▲]

Lexicografía e informática: sí, pero... / Lexicographie et informatique: oui, mais...

in Ruiz Miyares, Leonel; Álvarez Silva, María Rosa; Muñoz Alvarado, Alex (Eds.) Actualizaciones en Comunicación Social - Vol. 1 (2013)

Laboratory management of cervical intraepithelial neoplasia: proposing a new paradigm

in Advances in Anatomic Pathology (2013)

Novel functional degradable block copolymers for the building of reactive micelles

in Polymer Chemistry (2013), 4(4), 1025-1037

Amphiphilic biocompatible copolymers are promising materials for the elaboration of nanosystems for drug delivery applications. This paper aims at reporting on the synthesis of new functional amphiphilic ... [more ▼]

Amphiphilic biocompatible copolymers are promising materials for the elaboration of nanosystems for drug delivery applications. This paper aims at reporting on the synthesis of new functional amphiphilic copolymers based on biocompatible and bioeliminable blocks. Poly(ethylene oxide) was selected as the hydrophilic block, whereas an aliphatic polyester, i.e. poly(epsilon-caprolactone), or a polycarbonate, i.e. poly(trimethylene carbonate), were chosen as the degradable hydrophobic block. In order to allow a post-functionalization of the micelles core, azide groups were introduced on the hydrophobic segment to provide reactivity towards functional alkyne derivatives by the copper azide-alkyne cycloaddition (CuAAC). For this purpose, a functional lactone, i.e. alpha-chloro-epsilon-caprolactone was introduced during the polymerization of the hydrophobic block before being converted into azide on the preformed copolymer. Such reactivity of the block copolymers and their self-assemblies is of prime interest for drugs or fluorescent dyes grafting, so as for micelles cross-linking. The influence of the azides distribution along the degradable block on the micelles post-functionalization ability has been studied by using alkyne bearing fluorescent dyes as model for drugs. The hydrophilicity of the dye on the micelles post-functionalization efficiency has also been investigated. [less ▲]

Efficacité des méthodes de lutte contre le développement de cinq espèces de plantes invasives amphibies : Crassula helmsii , Hydrocotyle ranunculoides , Ludwigia grandiflora , Ludwigia peploides et Myriophyllum aquaticum (synthèse bibliographique)

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2013), 17(1), 88-103

Parmi les espèces invasives connaissant une expansion rapide en Europe, les plantes dites « amphibies » sont particulièrement problématiques. Elles sont capables de former des populations très denses à la ... [more ▼]

Parmi les espèces invasives connaissant une expansion rapide en Europe, les plantes dites « amphibies » sont particulièrement problématiques. Elles sont capables de former des populations très denses à la surface des plans d’eau, se développant à la fois sous l’eau et hors de l’eau. La lutte contre ces espèces, en vue de l’éradication totale ou du ralentissement de l’invasion, représente un défi de taille pour les gestionnaires. Une synthèse bibliographique des méthodes de lutte existantes pour Crassula helmsii, Hydrocotyle ranunculoides, Ludwigia grandiflora, L. peploides et Myriophyllum aquaticum a été réalisée, prenant en considération leur efficacité et leur coût. Des 88 études analysées, il ressort une grande disparité d’effort de recherche (nombre d’études, échelles spatiales des études) entre méthodes de lutte et entre espèces. Néanmoins, l’efficacité des différentes méthodes de lutte est comparable pour les cinq espèces étudiées. Globalement, les cas d’éradication sont rares. Ils sont le résultat de luttes mécaniques ou chimiques, souvent couplées à des interventions complémentaires telles que la finition manuelle. Malgré une forte occurrence dans la littérature, la lutte chimique, moins fastidieuse à mettre en place et moins coûteuse que les autres méthodes, n’a montré des niveaux d’efficacité satisfaisants qu’avec certaines matières actives. De même, la lutte biologique a montré peu de résultats encourageants à ce jour. Il est à noter que certains agents de lutte biologique sont d’ores et déjà considérés comme des espèces invasives en Europe. A contrario, malgré leur faible occurrence dans la littérature, l’arrachage manuel ou mécanique suivi de finitions manuelles a donné des niveaux d’efficacité satisfaisants. Vu les difficultés de lutter contre les espèces invasives amphibies et les dommages collatéraux potentiels sur les écosystèmes, un débat impliquant scientifiques, autorités et gestionnaires de plans d’eau devra avoir lieu afin de poser les bases d’une gestion cohérente à grande échelle. [less ▲]

Dispersion of multiwalled carbon nanotubes in water by lignin

in Journal of Materials Science (2013), 48(14), 4962-4964

Multiwalled carbon nanotubes (MWCNT) can be stably dispersed in water with small amount of lignin. One-step dispersion in the 20.0 g/L concentration range is achieved at room temperature with excellent ... [more ▼]

Multiwalled carbon nanotubes (MWCNT) can be stably dispersed in water with small amount of lignin. One-step dispersion in the 20.0 g/L concentration range is achieved at room temperature with excellent electrical properties of MWCNT. Lignin is depicted to act as an anti-static agent. [less ▲]

L'amour hors normes dans la Walkyrie

in Liber Amicorum Hélène Casman (2013)

Which agriculture can face climate change? Focus on varietal adaptation

Poster (2013)

Stochastic modeling in mechanics: course material

Learning material (2013)

Bolaamphiphiles Derived from Alkenyl L-rhamnosides and Alkenyl D-xylosides: Importance of the Hydrophilic Head

in Molecules (2013), REVISION

The two step synthesis of a new bolaamphiphile derived from alkenyl L-rhamnosides was described. The general synthetic strategy of bolaamphiphiles derived from L-rhamnose was based on a previous work ... [more ▼]

The two step synthesis of a new bolaamphiphile derived from alkenyl L-rhamnosides was described. The general synthetic strategy of bolaamphiphiles derived from L-rhamnose was based on a previous work describing the synthesis of bolaamphiphiles derived from D-xylose. The conformational properties of this new compound were investigated by FTIR spectroscopy in an aqueous film in order to obtain a reference for further studies about the membrane-interacting properties. Moreover, the surface activity of this new bolaamphiphile was analyzed by Langmuir balance technology and was compared with that of the analogous bolaamphiphile derived from alkenyl D-xylosides. The findings indicate that the rhamnoside-based bolaform has an increased surface activity and a better ability to form aggregates than xyloside-based one. [less ▲]