Boundary Layer Meteorol
August 2024
The exchange of momentum, heat and trace gases between atmosphere and surface is mainly controlled by turbulent fluxes. Turbulent mixing is usually parametrized using Monin-Obukhov similarity theory (MOST), which was derived for steady turbulence over homogeneous and flat surfaces, but is nevertheless routinely applied to unsteady turbulence over non-homogeneous surfaces. We study four years of eddy-covariance measurements at a highly heterogeneous alpine valley site in Finse, Norway, to gain insights into the validity of MOST, the turbulent transport mechanisms and the contributing coherent structures.
View Article and Find Full Text PDFThe presence of endotoxins in preparations of recombinantly produced therapeutic proteins poses serious problems for patients. Endotoxins can cause fever, respiratory distress syndromes, intravascular coagulation, or endotoxic shock. A number of methods have been devised to remove endotoxins from protein preparations using separation procedures based on molecular mass or charge properties.
View Article and Find Full Text PDFTwo limiting aspects are mainly responsible for the sluggish development of new cancer drugs. They concern the chemical properties of potential drug molecules and the structural prerequisites for drug targets. The chemical properties which are being considered desirable for potential drugs are rather restrictive and mainly dictated by the rules of oral availability.
View Article and Find Full Text PDFAbstract Cytotoxic agents, alone or in combination, are being used in the treatment of colorectal cancer. Despite progress in the therapeutic regimes, this common malignancy is still the cause of considerable morbidity and mortality, and further improvements are required. Cancer cells often exhibit intrinsic resistance against chemotherapeutic agents or they develop resistance over the time of treatment.
View Article and Find Full Text PDFAbstract Signal transducer and activator of transcription 3 (Stat3) assumes central functions in the regulation of apoptosis, proliferation, angiogenesis, and immune responses in normal cells. It also plays crucial roles in inflammatory and malignant diseases and in the cellular communication in the tissue microenvironment. Signaling interactions among normal endothelial cells, immune cells, and tumor cells, mediated by the release of cytokines, chemokines, and growth factors, often result in the activation of Stat3 and promotion of cancer cell proliferation, invasion, angiogenesis, and immune evasion.
View Article and Find Full Text PDFAbstract Deregulation of signal transducer and activator of transcription 3 (Stat3) is attracting attentions in neurological disorders of elderly populations, e.g., Stat3 is inactivated in hippocampal neurons of Alzheimer's disease (AD) brains, whereas it is often constitutively activated in glioblastoma multiforme (GBM), correlating with poor prognosis.
View Article and Find Full Text PDFBackground: Proteins involved in the aberrant regulation of signaling pathways and their downstream effectors are promising targets for cancer therapy. Survivin is an anti-apoptotic and cell cycle-promoting protein, which is consistently overexpressed in cancer cells. In normal cells, its expression is tightly controlled by signaling pathways and their associated transcriptional activators and repressors.
View Article and Find Full Text PDFCancer cells are characterized by the aberrant activation of signaling pathways governing proliferation, survival, angiogenesis, migration and immune evasion. These processes are partially regulated by the transcription factor STAT3. This factor is inappropriately activated in diverse tumor types.
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