Showing papers by "Martina Schmidt published in 2005"
TL;DR: In this paper, p63RhoGEF, a recently identified RhoA-specific guanine nucleotide exchange factor, enhances the Rhodependent gene transcription induced by agonist-stimulated G(q/11)-coupled receptors (M3-cholinoceptor, histamine H1 receptor) or GTPase-deficient mutants of G alpha(q) and G alpha11.
202 citations
TL;DR: Ishikawa cells respond to JAR contact as well as to treatment with toxin A with rearrangement of F-actin and small GTPase RhoA but seem to be able to modify signalling pathways in a way not elucidated so far in endometrial cells indicating an essential role of cell phenotype modification in apical adhesiveness of uterine epithelium for trophoblast in vivo.
Abstract: Embryo implantation requires that uterine epithelium develops competence to bind trophoblast to its apical (free) poles. This essential element of uterine receptivity seems to depend on a destabilisation of the apico-basal polarity of endometrial epithelium. Accordingly, a reorganisation of the actin cytoskeleton regulated by the small GTPase RhoA plays an important role in human uterine epithelial RL95-2 cells for binding of human trophoblastoid JAR cells. We now obtained new insight into trophoblast binding using human uterine epithelial Ishikawa cells.
46 citations
TL;DR: In this article, the authors present experimental evidence of modification of O2/N2/Ar and CO2 mole fraction in dry air standards resulting from gas handling using diffusive fractionation.
Abstract: [1] We present experimental evidence of modification of O2/N2, Ar/N2, 29N2/28N2, 34O2/32O2 ratios and CO2 mole fraction in dry air standards resulting from gas handling. Correlated variations among high precision measurements of multiple molecular pair ratios show diffusive fractionation to be the main modifying process. This mechanism can account for much of the previously unexplained CO2 instability commonly observed in air standards used by the atmospheric CO2 measurement community. Identification of the effects of diffusive fractionation helps to isolate effects of other processes such as surface adsorption, which is also implicated as a cause of CO2 modification in some applications. These findings have direct implications for the preparation and maintenance of O2/N2/Ar and CO2 calibration standards and are relevant to other atmospheric measurement activities that involve gas handling.
28 citations
TL;DR: In this paper, the first atmospheric O2, CO2 and δ13C measurements from the high altitude site Jungfraujoch (JFJ), Switzerland, as well as from the mountain site Puy de Dome (PUY), France are presented.
Abstract: [1] First atmospheric O2, CO2 and δ13C flask measurements from the high altitude site Jungfraujoch (JFJ), Switzerland, as well as from the mountain site Puy de Dome (PUY), France are presented. The four-year records of JFJ and the three-year records of PUY show distinct seasonal cycles and superimposed long-term trends in the measured parameters. The mean peak-to-peak amplitudes of the respective seasonal cycles at JFJ are 79 per meg for O2/N2, 11 ppm for CO2, and 0.45 ‰ for δ13C. At PUY the seasonal variations are about two times larger than at JFJ. The spring time CO2 maximum at PUY appears in early march, whereas at JFJ it shows up 1 to 2 months later. The O2:CO2 correlation gives at both sites slopes of about −2 mol O2/mol CO2. Stable carbon isotope ratios of source CO2 show depleted values in wintertime and isotopically enriched values in summer.
24 citations