33 research outputs found
Optical structure and function of the white filamentary hair covering the edelweiss bracts
The optical properties of the inflorescence of the high-altitude
''Leontopodium nivale'' subsp. ''alpinum'' (edelweiss) is investigated, in
relation with its submicrometer structure, as determined by scanning electron
microscopy. The filaments forming the hair layer have been found to exhibit an
internal structure which may be one of the few examples of a photonic structure
found in a plant. Measurements of light transmission through a self-supported
layer of hair pads taken from the bracts supports the idea that the wooly layer
covering the plant absorbs near-ultraviolet radiation before it reaches the
cellular tissue. Calculations based on a photonic-crystal model provides
insight on the way radiation can be absorbed by the filamentary threads.Comment: 9 pages, 13 figures. Published pape
Absence of aromatase protein and mRNA expression in endometriosis.
BACKGROUND: Aromatase has been reported to be involved in estrogen biosynthesis and expressed in eutopic and ectopic endometrium of endometriosis patients. The objective of the present study was to investigate its expression and localization in three distinct types of endometriosis. METHODS: Human peritoneal, ovarian and rectovaginal endometriotic lesions and matched eutopic endometrium were collected from patients during laparoscopy. Aromatase protein localization (immunohistochemistry, n = 63) and mRNA expression [quantitative polymerase chain reaction (Q-PCR), n = 64] were assessed. RESULTS: No aromatase protein was detected by immunohistochemistry in either the glandular or stromal compartment of endometriotic lesions or eutopic endometrium, while it was strong in placental syncytiotrophoblasts, granulosa and internal theca cells from pre-ovulatory follicles, and luteal cells from corpus luteum. By Q-PCR, low but discernible levels of aromatase expression were found in endometriomas, probably due to follicular expression. Transcripts for aromatase were barely detectable in only a few peritoneal and rectovaginal endometriotic lesions, and a few eutopic endometrium samples, probably due to contaminating surrounding tissues (adipose tissue, intact peritoneum). CONCLUSIONS: Unlike previous studies, we observed no aromatase protein in any of the endometriosis types, and barely detectable aromatase mRNA expression, suggesting that locally produced aromatase (within endometriotic lesions) may be less implicated in endometriosis development than previously postulated. Potential factors responsible for these discrepancies are discussed
Iridescent Coleoptera as templates for fabrication of versatile SiO /TiO multilayer mirrors and filters
Unsuccessful Induction of Endometriosis in Female Rhesus Macaques (Macaca mulatta).
Background/Aims: The aim of this study was to induce endometriosis in female rhesus macaques (Macaca mulatta) for research purposes. Methods: Three female monkeys from 4 to 4.5 years of age underwent three consecutive attempts at endometriosis induction over an 8-month period: (i) the first attempt involved intravaginal sampling of endometrial tissue and transplantation into the intrapelvic cavity; (ii) the second entailed surgical removal of endometrium after hysterotomy and intra-abdominal placement, and (iii) the third used endometrial mucosa obtained by scraping the uterus after hysterectomy, placed in a surgical pouch created in the retrovesical space (Retzius). In each case, the pelvic cavity was closely inspected after 7, 9, and 6 weeks respectively for the presence of endometriotic lesions, and peritoneal biopsies were performed. Results: Neither macroscopic observation nor histological analysis revealed any endometriotic lesions. Conclusion: This failure to induce endometriosis in female rhesus macaques suggests that this species is not the most efficient experimental model among primates to investigate endometriosis development or treatment
Société d'histoire du droit des pays flamands, picards et wallons. Journées internationales de Louvain (31 Mai 4 Juin 1956)
Rouhart-Chabot J., Balon Joseph, Bovesse J., Delhaye Philippe, Yans Maurice, Janne d'Othée X., Darquennes A., Petit Roger, Gorissen P., Warlomont René, Theluez C., Genicot Léopold, Van Dievoet Guy, Lousse E. Société d'histoire du droit des pays flamands, picards et wallons. Journées internationales de Louvain (31 Mai 4 Juin 1956) . In: Revue du Nord, tome 39, n°154, Avril-juin 1957. pp. 157-169
Société d'histoire du droit des pays flamands, picards et wallons. Journées internationales de Louvain (31 Mai 4 Juin 1956)
Rouhart-Chabot J., Balon Joseph, Bovesse J., Delhaye Philippe, Yans Maurice, Janne d'Othée X., Darquennes A., Petit Roger, Gorissen P., Warlomont René, Theluez C., Genicot Léopold, Van Dievoet Guy, Lousse E. Société d'histoire du droit des pays flamands, picards et wallons. Journées internationales de Louvain (31 Mai 4 Juin 1956) . In: Revue du Nord, tome 39, n°154, Avril-juin 1957. pp. 157-169