221 research outputs found
How two business models respond to current chalenges of agrowood production: the case of Brandenburg, Germany
PosterThe agrowood acreage in Brandenburg has increased fifteen-fold since 2008 reaching in 2013 1819ha (Ministerium für Infrastruktur und Landwirtschaft 2013) and therefore the leading position of all federal states in Germany. Despite of the constant rise and the chances associated with the production of agrowood, potential producers have to face a wide range of challenges: uncertainties about yields, high initial investments, a fixation of land for the 20 years` lifetime of an agrowood plantation and an irregular cash flow all 3 or 5 years. A non-transparent market in addition to lacking long term experiences and machinery available, affects the decision-making process of potential producers negatively. In Brandenburg this innovative crop, growing even under harsh conditions, matches the unfavorable agricultural conditions (Murach et al. 2008). Our subjects of investigation are the two prevailing business models in the agrowood sector in Brandenburg: comprehensive cooperation agreements and independent farming. They coexist and mutually interact with synergies as well as obstructions. We combine a qualitative method with guided interviews focusing on planting decision making processes with a modeling approach using different risk levels and yield expectations to analyze transaction and opportunity costs of those two models. Thereby the characteristics and effects of the business models are compared and analyzed. Our results show that cooperation agreements have effects on the actor`s decision by motivating farmers to decide in favor of agrowood. They also contribute to an expansion of agrowood acreage accounting for almost 40% of the total area in Brandenburg in 2012 (Ehm 2013). Furthermore cooperation agreements are affirmed by interviewees to overcome economic, trade and machinery related constraints of agrowood, secure long-term incomes and increase creditworthiness of producers. In contrast, independent producers are acknowledged to have the burden of higher risks, but may benefit from governmental support programs, which not apply for contract farmers
TCR-engineered T cells: a model of inducible TCR expression to dissect the interrelationship between two TCRs
TCR gene-modified T cells for adoptive therapy simultaneously express the transgenic (tg) TCR and the endogenous TCR which might lead to mispaired TCRs with harmful unknown specificity and to a reduced function of TCR-tg T cells. We generated dual TCR T cells in two settings in which either TCR was constitutively expressed by a retroviral promoter while the second TCR expression was regulable by a tet-on system. Constitutively expressed TCR molecules were reduced on the cell surface depending on the induced TCR expression leading to strongly hampered function. Besides that, using fluorescence resonance energy transfer (FRET) we detected mispaired TCR dimers and different pairing behaviors of individual TCR chains with a mutual influence on TCR chain expression. The loss of function and mispairing could not be avoided by changing the TCR expression level or by introduction of an additional cysteine bridge. However, in polyclonal T cells, optimized TCR formats (cysteineization, codon optimization) enhanced correct pairing and function. We conclude from our data that (i) the level of mispairing depends on the individual TCRs and is not reduced by increasing the level of one TCR, and (ii) modifications (cysteineization, codon optimization) improve correct pairing but do not completely exclude mispairing (cysteineization)
TCR-engineered T cells: a model of inducible TCR expression to dissect the interrelationship between two TCRs
TCR gene-modified T cells for adoptive therapy simultaneously express the transgenic (tg) TCR and the endogenous TCR which might lead to mispaired TCRs with harmful unknown specificity and to a reduced function of TCR-tg T cells. We generated dual TCR T cells in two settings in which either TCR was constitutively expressed by a retroviral promoter while the second TCR expression was regulable by a tet-on system. Constitutively expressed TCR molecules were reduced on the cell surface depending on the induced TCR expression leading to strongly hampered function. Besides that, using fluorescence resonance energy transfer (FRET) we detected mispaired TCR dimers and different pairing behaviors of individual TCR chains with a mutual influence on TCR chain expression. The loss of function and mispairing could not be avoided by changing the TCR expression level or by introduction of an additional cysteine bridge. However, in polyclonal T cells, optimized TCR formats (cysteineization, codon optimization) enhanced correct pairing and function. We conclude from our data that (i) the level of mispairing depends on the individual TCRs and is not reduced by increasing the level of one TCR, and (ii) modifications (cysteineization, codon optimization) improve correct pairing but do not completely exclude mispairing (cysteineization)
TCR-engineered T cells: A model of inducible TCR expression to dissect the interrelationship between two TCRs
TCR gene modified T cells for adoptive therapy simultaneously express the Tg TCR and the endogenous TCR, which might lead to mispaired TCRs with harmful unknown specificity and to a reduced function of TCR-Tg T cells. We generated dual TCR T cells in two settings in which either TCR was constitutively expressed by a retroviral promoter while the second TCR expression was regulable by a Tet-on system. Constitutively expressed TCR molecules were reduced on the cell surface depending on the induced TCR expression leading to strongly hampered function. Besides that, using fluorescence resonance energy transfer we detected mispaired TCR dimers and different pairing behaviors of individual TCR chains with a mutual influence on TCR chain expression. The loss of function and mispairing could not be avoided by changing the TCR expression level or by introduction of an additional cysteine bridge. However, in polyclonal T cells, optimized TCR formats (cysteineization, codon optimization) enhanced correct pairing and function. We conclude from our data that (i) the level of mispairing depends on the individual TCRs and is not reduced by increasing the level of one TCR, and (ii) modifications (cysteineization, codon optimization) improve correct pairing but do not completely exclude mispairing (cysteineization)
CD8 T cell tolerance to a tumor-associated self-antigen is reversed by CD4 T cells engineered to express the same T cell receptor
Ag receptors used for cancer immunotherapy are often directed against tumor-associated Ags also expressed in normal tissues. Targeting of such Ags can result in unwanted autoimmune attack of normal tissues or induction of tolerance in therapeutic T cells. We used a murine model to study the phenotype and function of T cells redirected against the murine double minute protein 2 (MDM2), a tumor-associated Ag that shows low expression in many normal tissues. Transfer of MDM2-TCR-engineered T cells into bone marrow chimeric mice revealed that Ag recognition in hematopoietic tissues maintained T cell function, whereas presentation of MDM2 in nonhematopoietic tissues caused reduced effector function. TCR-engineered CD8(+) T cells underwent rapid turnover, downmodulated CD8 expression, and lost cytotoxic function. We found that MDM2-TCR-engineered CD4(+) T cells provided help and restored cytotoxic function of CD8(+) T cells bearing the same TCR. Although the introduction of the CD8 coreceptor enhanced the ability of CD4(+) T cells to recognize MDM2 in vitro, the improved self-antigen recognition abolished their ability to provide helper function in vivo. The data indicate that the same class I-restricted TCR responsible for Ag recognition and tolerance induction in CD8(+) T cells can, in the absence of the CD8 coreceptor, elicit CD4 T cell help and partially reverse tolerance. Thus MHC class I-restricted CD4(+) T cells may enhance the efficacy of therapeutic TCR-engineered CD8(+) T cells and can be readily generated with the same TCR
ERK1 as a therapeutic target for dendritic cell vaccination against high-grade gliomas
Glioma regression requires the recruitment of potent anti-tumor immune cells into the tumor microenvironment. Dendritic cells (DCs) play a role in immune responses to these tumors. The fact that DC vaccines do not effectively combat high-grade gliomas, however, suggests that DCs need to be genetically modified especially to promote their migration to tumor relevant sites. Previously, we identified extracellular signal-regulated kinase (ERK1) as a regulator of DC immunogenicity and brain autoimmunity. In the present study, we made use of modern magnetic resonance methods to study the role of ERK1 in regulating DC migration and tumor progression in a model of high-grade glioma. We found that ERK1-deficient mice are more resistant to the development of gliomas, and tumor growth in these mice is accompanied by a higher infiltration of leukocytes. ERK1-deficient DCs exhibit an increase in migration that is associated with sustained Cdc42 activation and increased expression of actin-associated cytoskeleton-organizing proteins. We also demonstrated that ERK1 deletion potentiates DC vaccination and provides a survival advantage in high-grade gliomas. Considering the therapeutic significance of these results, we propose ERK1-deleted DC vaccines as an additional means of eradicating resilient tumor cells and preventing tumor recurrence
Laser Time-of-Flight Mass Spectrometry for Future In Situ Planetary Missions
Laser desorption/ionization time-of-flight mass spectrometry (LD-TOF-MS) is a versatile, low-complexity instrument class that holds significant promise for future landed in situ planetary missions that emphasize compositional analysis of surface materials. Here we describe a 5kg-class instrument that is capable of detecting and analyzing a variety of analytes directly from rock or ice samples. Through laboratory studies of a suite of representative samples, we show that detection and analysis of key mineral composition, small organics, and particularly, higher molecular weight organics are well suited to this instrument design. A mass range exceeding 100,000 Da has recently been demonstrated. We describe recent efforts in instrument prototype development and future directions that will enhance our analytical capabilities targeting organic mixtures on primitive and icy bodies. We present results on a series of standards, simulated mixtures, and meteoritic samples
Implementation of an End-to-End Standards-based Patient Monitoring Solution
A proof-of-concept design of a patient monitoring solution for intensive care unit environments has been presented. It is end-to-end standard-based, using ISO/IEEE 11073 (X73) in the bedside environment and EN13606 to communicate the information to an electronic healthcare record (EHR) server. At the bedside end, the system is a plug-and-play sensor network communicating with a gateway that collects medical information and sends the data to a monitoring server. The monitoring server transforms this information into an EN13606 extract to be stored on the EHR server. The system has been implemented to comply with the last X73 and EN13606 available versions and tested in a laboratory environment to demonstrate the feasibility of an end-to-end standard-based solution
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