49 research outputs found
Noninvasive in vivo tracking of mesenchymal stem cells and evaluation of cell therapeutic effects in a murine model using a clinical 3.0 T MRI
Cardiac cell therapy with mesenchymal stem cells (MSCs) represents a promising treatment approach for endstage heart failure. However, little is known about the underlying mechanisms and the fate of the transplanted cells. The objective of the presented work is to determine the feasibility of magnetic resonance imaging (MRI) and in vivo monitoring after transplantation into infarcted mouse hearts using a clinical 3.0 T MRI device. The labeling procedure of bone marrow-derived MSCs with micron-sized paramagnetic iron oxide particles (MPIOs) did not affect the viability of the cells and their cell type-defining properties when compared to unlabeled cells. Using a clinical 3.0 T MRI scanner equipped with a dedicated small animal solenoid coil, 105 labeled MSCs could be detected and localized in the mouse hearts for up to 4 weeks after intramyocardial transplantation. Weekly ECG-gated scans using T1-weighted sequences were performed, and left ventricular function was assessed. Histological analysis of hearts confirmed the survival of labeled MSCs in the target area up to 4 weeks after transplantation. In conclusion, in vivo tracking of labeled MSCs using a clinical 3.0 T MRI scanner is feasible. In combination with assessment of heart function, this technology allows the monitoring of the therapeutic efficacy of regenerative therapies in a small animal model. </jats:p
Dynamic Support Culture of Murine Skeletal Muscle-derived Stem Cells Improves Their Cardiogenic Potential In Vitro
Ischemic heart disease is the main cause of death in western countries and its burden is increasing worldwide. It typically involves irreversible degeneration and loss of myocardial tissue leading to poor prognosis and fatal outcome. Autologous cells with the potential to regenerate damaged heart tissue would be an ideal source for cell therapeutic approaches. Here, we compared different methods of conditional culture for increasing the yield and cardiogenic potential of murine skeletal muscle-derived stem cells. A subpopulation of nonadherent cells was isolated from skeletal muscle by preplating and applying cell culture conditions differing in support of cluster formation. In contrast to static culture conditions, dynamic culture with or without previous hanging drop preculture led to significantly increased cluster diameters and the expression of cardiac specific markers on the protein and mRNA level. Whole-cell patch-clamp studies revealed similarities to pacemaker action potentials and responsiveness to cardiac specific pharmacological stimuli. This data indicates that skeletal muscle-derived stem cells are capable of adopting enhanced cardiac muscle cell-like properties by applying specific culture conditions. Choosing this route for the establishment of a sustainable, autologous source of cells for cardiac therapies holds the potential of being clinically more acceptable than transgenic manipulation of cells
Canım
Selami Ä°zzet'in AkĆam'da tefrika edilen Canım adlı romanıTelif hakları nedeniyle romanın tam metni verilememiĆtir
Shallow non-inversion tillage in organic farming maintains crop yields and increases soil C stocks: a meta-analysis
Reduced tillage is increasingly promoted to improve sustainability and productivity of agricultural systems. Nonetheless, adoption of reduced tillage by organic farmers has been slow due to concerns about nutrient supply, soil structure, and weeds that may limit yields. Here, we compiled the results from both published and unpublished research comparing deep or shallow inversion tillage, with various categories of reduced tillage under organic management. Shallow refers to less than 25 cm. We found that (1) division of reduced tillage practices into different classes with varying degrees of intensity allowed us to assess the trade-offs between reductions in tillage intensity, crop yields, weed incidence, and soil C stocks. (2) Reducing tillage intensity in organic systems reduced crop yields by an average of 7.6 % relative to deep inversion tillage with no significant reduction in yield relative to shallow inversion tillage. (3) Among the different classes of reduced tillage practice, shallow non-inversion tillage resulted in non-significant reductions in yield relative to deep inversion; whereas deep non-inversion tillage resulted in the largest yield reduction, of 11.6 %. (4) Using inversion tillage to only a shallow depth resulted in minimal reductions in yield, of 5.5 %, but significantly higher soil C stocks and better weed control. This finding suggests that this is a good option for organic farmers wanting to improve soil quality while minimizing impacts on yields. (5) Weeds were consistently higher, by about 50 %, when tillage intensity was reduced, although this did not always result in reduced yields
Abstracts from the 8th International Conference on cGMP Generators, Effectors and Therapeutic Implications
This work was supported by a restricted research grant of Bayer AG
Auslastungsorientierte Erntelogistik: Routenplanung und Disposition von FeldhĂ€ckslern, Ăberladewagen und Transportfahrzeugen mit Synchronisationsnebenbedingungen
Agricultural contractors are logistics service providers for various field operations in agriculture. Restrictions imposed by nature, lack of personnel, high-priced agricultural machinery and small margins require contractors to make efficient use of their fleet of agricultural machinery. In order to achieve a short completion time, as is particularly necessary for harvesting, the dispatcher aims to minimize travel times between the operating locations and to increase the utilization of harvesting machines, e.g. forage harvesters and combine harvesters. This paper examines the harvesting process involving forage harvesters and support vehicles (transfer vehicles and transport vehicles). Here, if insufficient support vehicles are available, the forage harvester needs to pause operation on the field while waiting for a support vehicle that can receive the harvested biomass. Typically, teams of harvesters and support vehicles are assembled prior to the start of the harvesting process and remain in this constellation until all fields in the planning period have been harvested. In this study, we investigate the time savings when vehicles are not tied to their team and can thereby harvest each field in a new constellation of vehicles. This paper presents two mathematical models describing the harvesting process with forage harvesters, transfer vehicles and transporters with a focus on the utilization of the forage harvesters with fixed and variable team compositions, respectively. These models are solved via mixed-integer programming with the Gurobi solver.Landwirtschaftliche Lohnunternehmer sind Logistikdienstleister fĂŒr verschiedene Feldarbeiten in der Landwirtschaft. Naturgegebene Restriktionen, Personalmangel, hochpreisige Landmaschinen und geringe Margen erfordern von den Lohnunternehmern eine effiziente Auslastung ihres Landmaschinenparks. Um kurze Einsatzzeiten zu erreichen, wie es insbesondere bei der Ernte notwendig ist, werden kurze Fahrzeiten zwischen den Einsatzorten und eine hohe Auslastung der Erntemaschinen, z.B. FeldhĂ€cksler und MĂ€hdreschern, angestrebt. In diesem Beitrag wird der Ernteprozess mit FeldhĂ€ckslern und UnterstĂŒtzungsfahrzeugen (Ăberlade- und Transportfahrzeuge) untersucht. Dabei muss der FeldhĂ€cksler, wenn nicht genĂŒgend Begleitfahrzeuge zur VerfĂŒgung stehen, die Ernte auf dem Feld unterbrechen und auf ein Begleitfahrzeug warten, das die geerntete Biomasse aufnehmen kann. Typischerweise werden Teams aus Erntemaschinen und UnterstĂŒtzungsfahrzeugen vor Beginn des Erntevorgangs zusammengestellt und bleiben in dieser Konstellation, bis alle Felder im Planungszeitraum abgeerntet sind. Im Fokus dieser Studie steht die sich ergebende Zeitersparnis, wenn die Fahrzeuge nicht an ihr Team gebunden sind und somit jedes Feld in einer neuen Konstellation beernten können. In diesem Beitrag werden zwei mathematische Modelle vorgestellt, die den Ernteprozess mit FeldhĂ€ckslern, Ăbergabefahrzeugen und Transportern beschreiben, wobei der Schwerpunkt auf der Auslastung der FeldhĂ€cksler bei fester bzw. variabler Teamzusammensetzung liegt. Diese Modelle werden mittels gemischtganzzahliger Programmierung mit dem Solver Gurobi gelöst