Glande | EPFL Graph Search

Une glande est un organe des animaux ou des plantes qui synthétise une substance qui sera sécrétée. La substance libérée peut avoir un rôle dans la communication intercellulaire, comme les hormones qui sont émises dans la circulation sanguine (on parle de glande endocrine). Les glandes peuvent également produire des substances qui seront libérées dans des cavités corporelles, ou à l'extérieur : ce sont les glandes exocrines chez les animaux, ou les nectaires des fleurs Processus de sécrétion pour glandes exocrines :

mérocrine : forme la plus courante, se fait par exocytose (canal rejoignant la glande) ;
apocrine : expulsion de vésicules libres (glandes mammaires et glandes sudoripares) ;
holocrine : explosion de la cellule (glandes sébacées) ;
eccrine : diffusion simple au travers de la membrane plasmique comme la sécrétion mérocrine, mais, ici, le nom eccrine précise que la substance est sécrétée sur la peau (glandes sudoripares).

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Swiss Cancer Center (Gland, VD)

Patrick DeCaro

Cancer: growth caused by uncontrolled and abnormal cell division, resulting in a non-structured mass or tumor, serving no beneficial purpose to the body. Even though cancer is one of the leading fatal diseases of today's world, with no distinction for age, sex, or organ, it can be fought and cured. Prevention, early diagnosis, correct treatment and optimal rehabilitation are key factors that will allow to surpass such a difficult moment. The aim of a Swiss Cancer Center is to unite these different elements. Away from the noise and stress of the city, but still at mid point between two major scientific poles, Gland offers an ideal site. By completely integrating the building into the nature of the south facing lakeside site with the view of the mountains, the Swiss Cancer Center tries to become one with its surroundings. Its architecture plays a major role in the well being of patients and doctors. It attempts to humanize the medical world. The creation of parks, green areas, lounges, and the use of natural light and fresh air are only some of the steps undertaken that limit the stress factors plaguing hospitals. The calm and beauty of the site can thus flow through the building, infusing it with its inherent serenity. The goal is to take the human as a starting point and to rethink the medical institution from there. It is by striking a balance between functionality, efficiency, ecology, health, and humanity that this goal can be achieved.

2008

Hormonal regulation of Stat5 in the mammary gland - from signaling to morphogenesis

Sergio Klinke

The mammary gland development is regulated by steroid and peptide hormones and occurs mainly after birth, compared to the majority of the other organs in the body. The principal hormones responsible for the breast development are the estrogen, the progesterone, the growth hormone, the epidermal growth factor and the prolactin. The latter one is of specific interest since it is required for further development of the gland through pregnancy and lactation. During pregnancy and lactation, alveolar structures develop and differentiate into secretory cells. The signal transducer and activator of transcription 5 (Stat5) is known to be the main effector of prolactin signaling during pregnancy, inducing alveologenesis and differentiation of epithelial cells into secretory cells. I investigated if Stat5 has a role before pregnancy. Protein expression as well as mRNA expression analysis of glands from ovariectomized mice which were artificially stimulated with ovarian hormones (estrogen and progesterone) and control vehicle showed evidences that Stat5 expression can be stimulated by these two hormones. Contrary to the role established until now for stat5 in the mammary gland, I found by fluorescence visualization of Stat5-null epithelium as well as whole mount staining of the same glands that Stat5 is required even before pregnancy since null epithelium showed highly reduced growth already in 3 weeks-old virgin mice. This may indicate a new role for this protein in cell proliferation or survival in early stages of mouse mammary development. Furthermore, transplantation experiment of Stat5-null epithelium into wild-type recipient mice showed that pregnancy state was not able to rescue the normal phenotype. This may be due to complete loss of these cells which happened during the 5 weeks left for the transplanted epithelium to expand the cleared fat pad. This discovery opens a new debate on Stat5 role in the mammary gland development.

2008

Differential expression of two different homeobox gene families during mouse tegument morphogenesis

Denis Duboule

The expression of six genes belonging to two different homeobox gene families was studied during the embryonic and postnatal morphogenesis of head and body regions of the mouse integument. The first family included the Otx1 and Otx2 genes, both related to the orthodenticle Drosophila gene and the second was represented by four members of the Antennapedia class HOX genes: Hoxc8 and three Hoxd genes, d9, d11 and d13. In situ hybridizations with 35S labeled antisense RNA probes were performed on head serial frontonasal sections, as well as entire embryo and postnatal tail longitudinal sections. The expression of these genes shows a differential spatiotemporal pattern along the cephalo-caudal axis. In 12.5-day and 15.5-day embryos, the Otx2 gene expression is restricted to the nasal epithelium and its associated glands, while the Otx1 transcripts are present in both nasal and facial integuments, including nasal glands and hair vibrissa follicles. The Hoxc8 expression first appears in skin at 14.5 days of gestation in the sternal region and is extended at 16.5 days to the thoracic ventral and lumbar dorsal regions. The Hoxd9 and Hoxd11 genes are only expressed in the caudal skin from 14.5 days of gestation. The Hoxd13 transcripts are the last to appear, 2 days after birth, and are limited to the last epidermal cells to differentiate, i.e. those of the hair matrix of the caudal pelage hair follicles. Taken together, these observations strengthen the hypothesis that different homeobox gene families specify the regional identity of the skin in the cephalic and body regions.

1994

Hormonal regulation of Stat5 in the mammary gland - from signaling to morphogenesis

Sergio Klinke

2008