1,572 research outputs found

    Entwicklung eines Inkubationssystems für ein inverses Mikroskop zur Langzeitbeobachtung von Zellkulturen in gekammerten Objektträgern

    Get PDF
    Trifunctional bispecific antibodies open up new immunological possibilities in tumour treatment. Prior to clinical application, comprehensive investigations using animal models and in vitro examinations need to be done. To investigate long-term interactions between Various immunologically active blood cells and individual tumour cells in the presence of antibodies, we developed an incubation system for experimental cell cultures on an inverted microscope. The system consists of a perspex box with a central moisture chamber with integrated water reservoir, external air circulation heating, and a CO2 supply. The sterile cell cultures are located in the wells of a slide positioned within a depression in the water reservoir. The newly developed incubation system enables continuous observation over the long term of experiments under optimal cell cultures conditions in combination with modern video techniques

    Class-based control schemes for parameterized project scheduling heuristics

    Full text link
    Most scheduling problems are notoriously intractable, so the majority of algorithms for them are heuristic in nature. Priority rule-based methods still constitute the most important class of these heuristics. Of these, in turn, parameterized biased random sampling methods have attracted particular interest, due to the fact that they outperform all other priority rule-based methods known. Yet, even the 'best' such algorithms are unable to relate to the particularities of all possible instances of the problem at hand: usually there will exist instances on which other, e.g. the second- or third-best, algorithms perform better. We maintain that asking for the one best algorithm for a given problem may in fact be asking too much. The recently proposed concept of control schemes, which refers to algorithmic schemes allowing to guide the proceeding of parameterized algorithms, opens up ways to refine existing algorithms in this regard. By partitioning the set of all instances of a problem into equivalence classes and identifying algorithmic components that are suited for the respective classes, class-based control schemes constitute one way to achieve this goal. Using the resource-constrained project scheduling problem as a vehicle, we describe how to devise such control schemes, making systematic use of different scheduling schemes as well as random sampling schemes and priority rules. Results from extensive computational experimentation validate effectiveness and efficiency of our approach

    Simultaneous precise editing of multiple genes in human cells

    No full text
    Abstract. When double-strand breaks are introduced in a genome by CRISPR they are repaired either by non-homologous end joining (NHEJ), which often results i

    Emergency sonography : the use of focused assessment with sonography for trauma in mid-American trauma centers [abstract]

    Get PDF
    The use of Focused Assessment with Sonography for Trauma (FAST) has steadily increased as a safe, inexpensive, noninvasive, and quick alternative to other imaging modalities, such as computed tomography (CT), in evaluating free-fluid caused by trauma. However, lack of regulation makes it difficult to assess its prevalence and who is performing the scans. As a result, accuracy is widely variable depending on the person performing the scan and how much training they have received. The purpose of this study is to interview the trauma centers of Missouri with a survey to measure how much ultrasound is used in the emergency setting and who is performing the scans in the state

    Immunocytochemical Phenotyping of Disseminated Tumor Cells in Bone Marrow by uPA Receptor and CK18: Investigation of Sensitivity and Specificity of an Immunogold/Alkaline Phosphatase Double Staining Protocol

    Get PDF
    Phenotyping of cytokeratin (CK) 18-positive cells in bone marrow is gaining increasing importance for future prognostic screening of carcinoma patients. Urokinase-type plasminogen activator receptor (uPA-R) is one example of a potential aggressive marker for those cells. However, a valid and reliable double staining method is needed. Using monoclonal antibodies against uPA-R and CK18, we modified an immunogold/alkaline phosphatase double staining protocol. UPA-R/CK18-positive tumor cell controls exhibited black uPA-R staining in 15–80 of cases and red CK18 staining in almost 100 of tumor cells. Isotype- and cross-matched controls were completely negative. Bone marrow from healthy donors was always CK18-negative. Reproducibility of CK18-positive cell detection was estimated in a series of specimens from 61 gastric cancer patients comparatively stained with the single alkaline phosphatase-anti-alkaline phosphatase (APAAP) and our double staining method (106 bone marrow cells/patient). In four cases, double staining could not reproduce CK18-positive cells. In 34 cases it revealed fewer or equal numbers, and in 23 cases more CK18-positive cells than the APAAP method. Overall quantitative analysis of detected cell numbers (838 in APAAP, range 1–280 in 106; double staining 808, range 0–253) demonstrated relative reproducibility of APAAP results by double staining of 97. Correlation of results between both methods was significant (p<0.001, linear regression). Sensitivity of double staining tested in logarithmic tumor cell dilutions was one CK18-positive cell in 300,000. Specific uPA-R staining was seen on CK18-positive cells in bone marrow from 29 of 61 patients, and also on single surrounding bone marrow cells. To test the specificity of this staining, bone marrow cytospins from 10 patients without tumor disease were stained for uPA-R with the APAAP method. uPA-R expression was confirmed in all 10 cases, with a mean of 6.5 uPA-R-positive cells in 1000 bone marrow cells (SEM 1.2). These results suggest that our double staining protocol is a sensitive, reproducible, and specific method for routine uPA-R phenotyping of disseminated CK18-positive cells in bone marrow of carcinoma patients

    Systemevaluierung "KMU-innovativ"

    Get PDF
    Der vorliegende Bericht stellt die Ergebnisse einer Systemevaluierung der Förderinitiative KMU-innovativ des BMBF dar. Die Evaluierung startete Ende 2008 und damit ein Jahr nach dem Beginn der Förderinitiative im Herbst 2007. Sie hatte zum Ziel, die Implementation, Zielerreichung und Wirkung der Förderinitiative sowie ihre Position in der Förderlandschaft zu bewerten. Die hier vorgelegten Ergebnisse bilden die Erfahrungen der ersten dreieinhalb Jahre der Umsetzung von KMU-innovativ ab

    Patient and nurse preferences for nurse handover - using preferences to inform policy: a discrete choice experiment protocol

    Get PDF
    Introduction Nursing bedside handover in hospital has been identified as an opportunity to involve patients and promote patient-centred care. It is important to consider the preferences of both patients and nurses when implementing bedside handover to maximise the successful uptake of this policy. We outline a study which aims to (1) identify, compare and contrast the preferences for various aspects of handover common to nurses and patients while accounting for other factors, such as the time constraints of nurses that may influence these preferences.; (2) identify opportunities for nurses to better involve patients in bedside handover and (3) identify patient and nurse preferences that may challenge the full implementation of bedside handover in the acute medical setting. Methods and analysis We outline the protocol for a discrete choice experiment (DCE) which uses a survey design common to both patients and nurses. We describe the qualitative and pilot work undertaken to design the DCE. We use a D-efficient design which is informed by prior coefficients collected during the pilot phase. We also discuss the face-to-face administration of this survey in a population of acutely unwell, hospitalised patients and describe how data collection challenges have been informed by our pilot phase. Mixed multinomial logit regression analysis will be used to estimate the final results. Ethics and dissemination This study has been approved by a university ethics committee as well as two participating hospital ethics committees. Results will be used within a knowledge translation framework to inform any strategies that can be used by nursing staff to improve the uptake of bedside handover. Results will also be disseminated via peer-reviewed journal articles and will be presented at national and international conferences

    Methods to increase the efficiency of precise CRISPR genome editing

    Get PDF
    Pluripotente Stammzellen haben das Potential, in unterschiedliche Zelltypen zu differenzieren und können genutzt werden, um organähnliche Mikrostrukturen zu generieren. Somit können molekulare Unterschiede verschiedenster künstlich differenzierter Gewebe, etwa zwischen Mensch und Schimpanse, anhand von pluripotenten Ausgangszellen untersucht werden. Da die Genome unserer nächsten ausgestorbenen Verwandten Neandertaler und Denisovaner aus konservierter DNA in alten Knochen sequenziert wurden, könnten ebenso Unterschiede zwischen Mensch und diesen Spezies oder dem letzten gemeinsamen Vorfahren untersucht werden. Dies erfordert jedoch die Generierung neandertalisierter Stammzellen durch künstliche Integration von Neandertalerallelen in humane Stammzellen, etwa durch die CRISPR Genomeditierungstechnik. Durch CRISPR kann ein DNA-Doppelstrangbruch an einer gewünschten Stelle im Genom eingefügt werden. Die zelluläre Reparatur des Doppelstrangbruchs ermöglicht dann die Editierung des Genoms. Basierend auf einer DNA-Matrize, die die gewünschte Modifikation trägt, kann das Genom an dieser Stelle präzise editiert werden. Die Effizienz präziser Editierung ist jedoch sehr niedrig im Vergleich zu unpräziser Reparatur. Um möglichst effizient neandertalisierte Stammzellen generieren zu können, wurden im Zuge dieser Doktorarbeit Methoden entwickelt, welche die präzise Genomeditierungseffizienz drastisch steigern. Zum einen wurde aus mehreren niedermolekularen Substanzen, welche mit Proteinen der DNA-Reparaturen interagieren, ein optimierter Mix entwickelt. Weiterhin konnte durch eine Mutation in einem zentralen Reparaturprotein die Effizienz für die Editierung eines einzelnen Gens auf 87% erhöht werden. Diese hohe Effizienz ermöglicht erstmals die präzise homozygote Editierung von vier Genen auf einmal in ein und derselben Zell
    corecore