On-line and real time cell counting and viability determination for animal cell process monitoring by in situ microscopy

International audienc

Antiproliferative Effects of DNA Methyltransferase 3B Depletion Are Not Associated with DNA Demethylation

Silencing of genes by hypermethylation contributes to cancer progression and has been shown to occur with increased frequency at specific genomic loci. However, the precise mechanisms underlying the establishment and maintenance of aberrant methylation marks are still elusive. The de novo DNA methyltransferase 3B (DNMT3B) has been suggested to play an important role in the generation of cancer-specific methylation patterns. Previous studies have shown that a reduction of DNMT3B protein levels induces antiproliferative effects in cancer cells that were attributed to the demethylation and reactivation of tumor suppressor genes. However, methylation changes have not been analyzed in detail yet. Using RNA interference we reduced DNMT3B protein levels in colon cancer cell lines. Our results confirm that depletion of DNMT3B specifically reduced the proliferation rate of DNMT3B-overexpressing colon cancer cell lines. However, genome-scale DNA methylation profiling failed to reveal methylation changes at putative DNMT3B target genes, even in the complete absence of DNMT3B. These results show that DNMT3B is dispensable for the maintenance of aberrant DNA methylation patterns in human colon cancer cells and they have important implications for the development of targeted DNA methyltransferase inhibitors as epigenetic cancer drugs

Dynamisches Boarding für Kurzstreckenflugzeuge

Der Einsatz aktueller und zukünftiger Kurzstreckenflugzeuge erfordert eine Fokussierung auf effiziente Bodenabfertigungsprozesse und hier im Besonderen auf das kritische Boarding, welches hauptsächlich durch das individuelle (Ankunfts-) Verhalten der Passagiere bestimmt wird. Hier setzt das dynamische Boardingkonzept seatNow an, welches in enger Zusammenarbeit mit Eurowings unter realen Bedingungen am Flughafen Köln/Bonn erfolgreich getestet wurde

Design and implementation of a service-oriented driver architecture for LINC-NIRVANA

LINC-NIRVANA (LN) is a German-Italian Fizeau (imaging) interferometer for the Large Binocular Telescope (LBT). The Instrument Control Software (ICS) of this instrument is a hierarchical, distributed software package, which runs on several computers. In this paper we present the bottom layer of the hierarchy - the Basic Device Application (BASDA) layer. This layer simplifies the development of the ICS through a general driver architecture, which supports different types of hardware. This generic device architecture provides a high level interface to encapsulate the hardware dependent driver. The benefit of such a device architecture is to keep the basic device-driver layer flexible and independent from the hardware, and to keep the hardware transparent to the ICS. Additionally, the basic device-driver layer supports interfaces to IDL based applications for calibration and laboratory testing of astronomical instruments, and interfaces to engineering GUIs that allow to maintain the software components easily

Optical Sampling in Situ Microscope for On-Line Monitoring of Animal Cell Cultures

International audienceCell concentration and cell vitality are key parameters to be monitored during cell cultivation processes. Common techniques used for these purposes are often based on sterile sampling and subsequent off line measurements. Extraction and preparation of samples is labour-intensive and risk-entailing. These disadvantages are avoided if the cell culture is directly inspected by using an in-situ technique, e.g. an in-situ microscope (ISM). An ISM delivers a wealth of image data which can be evaluated so as to provide automatic monitoring of the cell density and of morphological parameters as the cell-size. In-situ microscopy can either employ periodic opening and closing of a probe chamber inside the reactor or, alternatively, flash illumination and optical depth of field in order to define a virtual probe zone. Here, we describe optics and software of an advanced version of such an ISM with unprecedented resolution and frame rate. Fast collection of online-galleries of individual cell-portraits even at low cell concentrations enables online morphological analysis without sample extraction. Cell density data obtained by the ISM and traditional counting are shown in comparison, revealing the advantage of the ISM with respect to statistic deviations

The MCAO wavefront sensing system of LINC-NIRVANA: status report

LINC-NIRVANA is an infrared camera that will work in Fizeau interferometric way at the Large Binocular Telescope (LBT). The two beams that will be combined in the camera are corrected by an MCAO system, aiming to cancel the turbulence in a scientific field of view of 2 arcminutes. The MCAO wavefront sensors will be two for each arm, with the task to sense the atmosphere at two different altitudes (the ground one and a second height variable between a few kilometers and a maximum of 15 kilometers). The first wavefront sensor, namely the Ground layer Wavefront sensor (GWS), will drive the secondary adaptive mirror of LBT, while the second wavefront sensor, namely the Mid High layer Wavefront Sensor (MHWS) will drive a commercial deformable mirror which will also have the possibility to be conjugated to the same altitude of the correspondent wavefront sensor. The entire system is of course duplicated for the two telescopes, and is based on the Multiple Field of View (MFoV) Layer Oriented (LO) technique, having thus different FoV to select the suitable references for the two wavefront sensor: the GWS will use the light of an annular field of view from 2 to 6 arcminutes, while the MHWS will use the central 2 arcminutes part of the FoV. After LINC-NIRVANA has accomplished the final design review, we describe the MFoV wavefront sensing system together with its current status