Cervix | EPFL Graph Search

The cervix (: cervices) or cervix uteri (Latin, "neck of the uterus") is the lower part of the uterus (womb) in the human female reproductive system. The cervix is usually 2 to 3 cm long (~1 inch) and roughly cylindrical in shape, which changes during pregnancy. The narrow, central cervical canal runs along its entire length, connecting the uterine cavity and the lumen of the vagina. The opening into the uterus is called the internal os, and the opening into the vagina is called the external os. The lower part of the cervix, known as the vaginal portion of the cervix (or ectocervix), bulges into the top of the vagina. The cervix has been documented anatomically since at least the time of Hippocrates, over 2,000 years ago. The cervical canal is a passage through which sperm must travel to fertilize an egg cell after sexual intercourse. Several methods of contraception, including cervical caps and cervical diaphragms, aim to block or prevent the passage of sperm through the cervi

Local optical characterization of biological tissues in vitro and in vivo

Two methods for measuring the optical properties of tissue, i.e. reduced scattering and absorption coefficient, were developed. The first one was designed for in vitro investigations. It is based on the measurement of the spatially resolved transmittance through a tissue slab (typically 5 mm thick). The second one was designed for local in vivo investigations. It is based on the measurement of the spatially-resolved diffuse reflectance, close to the source (< 2 mm). A sterilizable probe, of diameter of 2.2 mm was realized for measurements in clinic, during surgery or endoscopy. A model of the light propagation in turbid media was developed based on Monte Carlo simulations. It allows us to establish the correspondence between the optical coefficients to the experimental data (spatially-resolved transmittance or reflectance). The influence of the scattering phase function on the reflectance and transmittance was carefully studied. In particular, the role of the first and the second moment of the phase function were shown for short distances measurements (close to one transport mean free path). Similarity relations, taking into account the first and second moment of the phase function were proposed and assessed. The model was tested extensively by measurements on tissue-like phantoms, with known optical properties. Further assessments of the model were performed by comparison with time-resolved measurements. Investigations on human brain, breast and cervix tissues were performed. Tissue structure (i.e. heterogeneities not taken into account by the model) were found to play a significant role in the light propagation. Normal and malignant brain tissue were investigated in vitro, and in vivo during surgery. Significant differences were found between different type of tissues, and were explained in terms of chromophore content (hemoglobin, water) and specific features of scattering properties.

EPFL1998

Notch1 mediates uterine stromal differentiation and is critical for complete decidualization in the mouse

Freddy Radtke

Uterine receptivity implies a dialogue between the hormonally primed maternal endometrium and the free-floating blastocyst. Endometrial stromal cells proliferate, avert apoptosis, and undergo decidualization in preparation for implantation; however, the molecular mechanisms that underlie differentiation into the decidual phenotype remain largely undefined. The Notch family of transmembrane receptors transduce extracellular signals responsible for cell survival, cell-to-cell communication, and differentiation, all fundamental processes for decidualization and pregnancy. Using a murine artificial decidualization model, pharmacological inhibition of Notch signaling by gamma-secretase inhibition resulted in a significantly decreased deciduoma. Furthermore, a progesterone receptor (PR)-Cre Notch1 bigenic (Notch1d/d) confirmed a Notch1-dependent hypomorphic decidual phenotype. Microarray and pathway analysis, following Notch1 ablation, demonstrated significantly altered signaling repertoire. Concomitantly, hierarchical clustering demonstrated Notch1-dependent differences in gene expression. Uteri deprived of Notch1 signaling demonstrated decreased cellular proliferation; namely, reduced proliferation-specific antigen, Ki67, altered p21, cdk6, and cyclinD activity and an increased apoptotic-profile, cleaved caspase-3, Bad, and attenuated Bcl2. The results demonstrate that the preimplantation uterus relies on Notch signaling to inhibit apoptosis of stromal fibroblasts and regulate cell cycle progression, which together promotes successful decidualization. In summary, Notch1 signaling modulates multiple signaling mechanisms crucial for decidualization and these studies provide additional perspectives to the coordination of multiple signaling modalities required during decidualization.-Afshar, Y., Jeong, J.-W., Roqueiro, D., DeMayo, F., Lydon, J., Radtke, F., Radnor, R., Miele, L., Fazleabas, A. Notch1 mediates uterine stromal differentiation and is critical for complete decidualization in the mouse. FASEB J. 26, 282-294 (2012). www.fasebj.org

Federation of American Society of Experimental Biology2012

Local optical characterization of biological tissues in vitro and in vivo

EPFL1998

Notch1 mediates uterine stromal differentiation and is critical for complete decidualization in the mouse

Freddy Radtke

Federation of American Society of Experimental Biology2012