Regulation des Aktivierungs-Induzierten Zelltods in peripheren humanen T-Zellen duch das antiapoptotischen Protein c-FLIP

Apoptose ist ein wichtiger Mechanismus zur Aufrechterhaltung der T-Zell-Homöostase. Das zu Procaspase-8 homologe Protein c-FLIP ist ein wichtiger Regulator der zellulären Sensitivität für todesrezeptorabhängige Apoptose. In der vorliegenden Arbeit wird die Regulation der Apoptosesensitivität primärer T-Lymphocyten durch Regulation der Expression von c-FLIP analysiert. Es wird gezeigt, dass die Expression von c-FLIP durch Stimulation des T-Zell-Rezeptors sowohl in naiven als auch in aktivierten T-Lymphocyten induziert wird. Die Abhängigkeit der c-FLIP-Expression von zwei differenziell regulierten Promotoren wird erstmalig demonstriert

Tissue culture conditions determine the effects of estrogen and growth factors on the anchorage independent growth of human breast cancer cell lines

We determined the effect of epidermal growth factor, insulin-like-growth-factor-1 and estradiol on the anchorage independent growth of the estrogen receptor positive human breast cancer cell lines MCF7 and T-47D. In serum free conditions growth factors but not estrogen induced a dose dependent stimulation of growth in both cell lines. The ability of estrogen to induce colony formation of early passage MCF7 cells ( 1000) MCF7 and T-47D cells. The growth of late passage MCF7 cells was inhibited by antiestrogen. Thus, the presence of serum components is necessary for the effect of estrogen but not for the effects of growth factors on the anchorage independent growth of estrogen receptor positive human breast cancer cell lines; after a prolonged period of tissue culture serum components switch their function from indirectly modulating estrogen effects to directly stimulating growth in the absence of estrogen

Observation Of Field-induced Single Impurity Behavior In The Heavy Fermion Compound Ce3 Co4 Sn13

We have performed heat capacity measurements in magnetic fields to 90 kOe on single crystals of the cubic heavy fermion compound Ce3 Co4 Sn13. In zero field, there are no signs of long-range magnetic order down to 0.35 K. However, C / T increases rapidly below 2 K, reaching a very large maximum value of ∼ 4 J / mol Ce-K around 0.8 K in zero field, and the high-field magnetic entropy approaches R ln 2 at 20 K. Above 25 kOe, the data are consistent with a Kondo impurity with TK = 1.2 K. Short-range magnetic correlations are suppressed by magnetic fields giving way to single impurity behavior above 25 kOe. © 2006 Elsevier B.V. All rights reserved.378-380SPEC. ISS.113114Takayanagi, S., (1994) Physica B, 199-200, p. 49Isreal, C., (2005) Physica B, 359-361, p. 251Niepmann, D., (2001) Z. Naturforsch., 56 b, p. 1Sacramento, P.D., Schlottmann, P., (1989) Phys. Rev. B, 40, p. 431Killer, U., (2004) Phys. Rev. Lett., 93, p. 216404Light, B.E., (2004) Phys. Rev. B, p. 02441

Negative Feedback Regulation of MKK6 mRNA Stability by p38α Mitogen-Activated Protein Kinase

p38 mitogen-activated protein (MAP) kinases play an important role in the regulation of cellular responses to all kinds of stresses. The most abundant and broadly expressed p38 MAP kinase is p38α, which can also control the proliferation, differentiation, and survival of several cell types. Here we show that the absence of p38α correlates with the up-regulation of one of its upstream activators, the MAP kinase kinase MKK6, in p38α(−/−) knockout mice and in cultured cells derived from them. In contrast, the expression levels of the p38 activators MKK3 and MKK4 are not affected in p38α-deficient cells. The increase in MKK6 protein concentration correlates with increased amounts of MKK6 mRNA in the p38α(−/−) cells. Pharmacological inhibition of p38α also up-regulates MKK6 mRNA levels in HEK293 cells. Conversely, reintroduction of p38α into p38α(−/−) cells reduces the levels of MKK6 protein and mRNA to the normal levels found in wild-type cells. Moreover, we show that the MKK6 mRNA is more stable in p38α(−/−) cells and that the 3′untranslated region of this mRNA can differentially regulate the stability of the lacZ reporter gene in a p38α-dependent manner. Our data indicate that p38α can negatively regulate the stability of the MKK6 mRNA and thus control the steady-state concentration of one of its upstream activators

Dynamic fluctuations of protein-carbohydrate interactions promote aggregation

Protein-carbohydrate interactions are important for glycoprotein structure and function. Antibodies of the IgG class, with increasing significance as therapeutics, are glycosylated at a conserved site in the constant Fc region. We hypothesized that disruption of protein-carbohydrate interactions in the glycosylated domain of antibodies leads to the exposure of aggregation-prone motifs. Aggregation is one of the main problems in protein-based therapeutics because of immunogenicity concerns and decreased efficacy. To explore the significance of intramolecular interactions between aromatic amino acids and carbohydrates in the IgG glycosylated domain, we utilized computer simulations, fluorescence analysis, and site-directed mutagenesis. We find that the surface exposure of one aromatic amino acid increases due to dynamic fluctuations. Moreover, protein-carbohydrate interactions decrease upon stress, while protein-protein and carbohydrate-carbohydrate interactions increase. Substitution of the carbohydrate-interacting aromatic amino acids with non-aromatic residues leads to a significantly lower stability than wild type, and to compromised binding to Fc receptors. Our results support a mechanism for antibody aggregation via decreased protein-carbohydrate interactions, leading to the exposure of aggregation-prone regions, and to aggregation.Novartis Pharma A

Personalized Treatment Selection and Disease Monitoring Using Circulating Tumor DNA Profiling in Real-World Cancer Patient Management

BACKGROUND Circulating tumor DNA (ctDNA) in the blood plasma of cancer patients is an emerging biomarker used across oncology, facilitating noninvasive disease monitoring and genetic profiling at various disease milestones. Digital droplet PCR (ddPCR) technologies have demonstrated high sensitivity and specificity for robust ctDNA detection at relatively low costs. Yet, their value for ctDNA-based management of a broad population of cancer patients beyond clinical trials remains elusive. METHODS We developed mutation-specific ddPCR assays that were optimized for their use in real-world cancer management, covering 12 genetic aberrations in common cancer genes, such as EGFR, BRAF, KIT, KRAS, and NRAS. We assessed the limit of detection (LOD) and the limit of blank (LOB) for each assay and validated their performance for ctDNA detection using matched tumor sequencing. RESULTS We applied our custom ddPCR assays to 352 plasma samples from 96 patients with solid tumors. Mutation detection in plasma was highly concordant with tumor sequencing, demonstrating high sensitivity and specificity across all assays. In 20 cases, radiographic cancer progression was mirrored by an increase of ctDNA concentrations or the occurrence of novel mutations in plasma. Moreover, ctDNA profiling at diagnosis and during disease progression reflected personalized treatment selection through the identification of actionable gene targets in 20 cases. CONCLUSION Collectively, our work highlights the potential of ctDNA assessment by sensitive ddPCR for accurate disease monitoring, robust identification of resistance mutations, and upfront treatment selection in patients with solid tumors. We envision an increasing future role for ctDNA profiling within personalized cancer management in daily clinical routine

Supplementary_Material – Supplemental material for Transcranial Direct Current Stimulation Enhances Motor Skill Learning but Not Generalization in Chronic Stroke

<p>Supplemental material, Supplementary_Material for Transcranial Direct Current Stimulation Enhances Motor Skill Learning but Not Generalization in Chronic Stroke by Manuela Hamoudi, Heidi M. Schambra, Brita Fritsch, Annika Schoechlin-Marx, Cornelius Weiller, Leonardo G. Cohen, and Janine Reis in Neurorehabilitation and Neural Repair</p