University of Geneva

About: University of Geneva is a education organization based out in Geneva, Switzerland. It is known for research contribution in the topics: Population & Galaxy. The organization has 26887 authors who have published 65265 publications receiving 2931373 citations. The organization is also known as: Geneva University & Universite de Geneve.

Apoptosis mediates the decrease in cellularity during the transition between granulation tissue and scar.

Abstract: Granulation tissue formation and contraction is an important step of second intention wound healing. Granulation tissue develops from the connective tissue surrounding the damaged or missing area and its cellular components are mainly small vessel and inflammatory cells as well as fibroblasts and myofibroblasts. As the wound closes and evolves into a scar, there is an important decrease in cellularity; in particular myofibroblasts disappear. The question arises as to which process is responsible for this cellular loss. During a previous investigation on the expression of alpha-smooth muscle actin in myofibroblasts (Darby I, Skalli O, Gabbiani G, Lab Invest, 1990, 63:21-29), we have observed that in late phases of wound healing, many myofibroblasts show changes compatible with apoptosis and suggested that this type of cell death could be responsible for the disappearance of myofibroblasts. We have now tested this hypothesis by means of morphometry at the electron microscopic level and by in situ end labeling of fragmented DNA. Our results indicate that the number of myofibroblastic and vascular cells undergoing apoptosis increases as the wound closes and support the assumption that this is the mechanism of granulation tissue evolution into a scar. The regulation of apoptotic phenomena during wound healing may be important in scar establishment and development of pathological scarring.

The present moment in psychotherapy and everyday life

Abstract: PART I. Exploring the Present Moment PART II. Contextualizing the Present Moment PART III. Views from a Clinical Perspective APPENDIX. The Micro-Analytic Interview

Proteasome-Independent Functions of Ubiquitin in Endocytosis and Signaling

Abstract: Ubiquitination is a reversible posttranslational modification of cellular proteins, in which a 76-amino acid polypeptide, ubiquitin, is primarily attached to the epsilon-amino group of lysines in target proteins. Ubiquitination is a major player in regulating a broad host of cellular processes, including cell division, differentiation, signal transduction, protein trafficking, and quality control. Aberrations in the ubiquitination system are implicated in pathogenesis of some diseases, certain malignancies, neurodegenerative disorders, and pathologies of the inflammatory immune response. Here, we discuss the proteasome-independent roles of ubiquitination in signaling and endocytosis.

POLYPHASIC CHLOROPHYLL a FLUORESCENCE TRANSIENT IN PLANTS AND CYANOBACTERIA

Abstract: The variable chlorophyll (Chl) a fluorescence yield is known to be related to the photochemical activity of photosystem I1 (PSII) of oxygen-evolving organisms. The kinetics of the fluorescence rise from the minimum yield, F,, to the maximum yield, F,, is a monitor of the accumulation of net reduced primary bound plastoquinone (QA) with time in all the PSII centers. Using a shutter-less system (Plant Efficiency Analyzer, Hansatech, UK), which allows data accumulation over several orders of magnitude of time (40 11s to 120 s), we have measured on a logarithmic time scale, for the first time, the complete polyphasic fluorescence rise for a variety of oxygenic plants and cyanobacteria at different light intensities. With increasing light intensity, the fluorescence rise is changed from a typical 0-I-P characteristic to curves with two intermediate levels J and I, both of which show saturation at high light intensity but different intensity dependence. Under physiological conditions, Chl a fluorescence transients of all the organisms examined follow the sequence of 0-J-I-P. The characteristics of the kinetics with respect to light intensity and temperature suggest that the 0-J phase is the photochemical phase, leading to the reduction of QA to QA-. The intermediate level I is suggested to be related to a heterogeneity in the filling up of the plastoquinone pool. The P is reached when all the plastoquinone (PQ) molecules are reduced to PQH2. The addition of 3-(3-4-dichIorophenyl)- 1,l -dimethylurea leads to a transformation of the 0-J-I-P rise into an 0-J rise. The kinetics of 0-J-I-P observed here was found to be similar to that of 0-1,-12-P, reported by Neubauer and Schreiber (2. Naturforsch. 42c, 1246-1254, 1987). The biochemical significance of the fluorescence steps 0-J-I-P with respect to the filling up of the plasto- quinone pool by PSII reactions is discussed.