Search results for "trace"
showing 10 items of 3218 documents
Determination of aragonite trace element distribution coefficients from speleothem calcite–aragonite transitions.
2016
The processes that govern the incorporation of (trace) elements into speleothems can often be linked to environmental changes. Although element incorporation into speleothem calcite is now reasonably well understood, current knowledge regarding trace element variability in speleothem aragonite is very limited. Of particular interest is whether trace element distribution coefficients are above or below one in order to assess the extent to which prior aragonite precipitation has affected speleothem aragonite trace element records. This study uses nine calcite-to-aragonite transitions in seven speleothems from diverse environmental settings to derive the first quantitative estimates of the dis…
Dibutyryl cyclic AMP and adrenaline increase contractile force and 45Ca uptake in mammalian cardiac muscle
1973
The effects of dibutyryl cyclic AMP (DB-AMP; 10−3M) and adrenaline (2.2×10−6 M) on contractile force, 45Ca uptake, and total myocardial Ca concentration were investigated in electrically driven left auricles isolated from rat hearts. The experiments were performed at an extracellular Ca concentration of 0.45 mM and at low frequency of stimulation (15 beats/min). 45Ca exposure was 5 min. Under the conditions used, both drugs increased contractile force and enhanced 45Ca uptake (expressed as relative specific activity) by about 30% (DB-AMP) and 40% (adrenaline), respectively. Thus, the results provide evidence that the effects of adrenaline on 45Ca uptake in mammalian cardiac muscle can be mi…
Rebalancing β-Amyloid-Induced Decrease of ATP Level by Amorphous Nano/Micro Polyphosphate: Suppression of the Neurotoxic Effect of Amyloid β-Protein …
2017
Morbus Alzheimer neuropathology is characterized by an impaired energy homeostasis of brain tissue. We present an approach towards a potential therapy of Alzheimer disease based on the high-energy polymer inorganic polyphosphate (polyP), which physiologically occurs both in the extracellular and in the intracellular space. Rat pheochromocytoma (PC) 12 cells, as well as rat primary cortical neurons were exposed to the Alzheimer peptide Aβ25-35. They were incubated in vitro with polyphosphate (polyP); ortho-phosphate was used as a control. The polymer remained as Na+ salt; or complexed in a stoichiometric ratio to Ca2+ (Na-polyP[Ca2+]); or was processed as amorphous Ca-polyP microparticles (C…
Characterisation of tumour-associated antigens in colon cancer.
2002
In order to search for clinically relevant cancer-associated genes and to define further the spectrum of immunogenic proteins, we applied SEREX (serological identification of antigens by recombinant expression cloning) to analyse genes expressed in colon adenocarcinoma. Eight different serum-reactive cDNA clones were isolated by immunoscreening from a colon cancer-derived cDNA expression library. mRNA expression studies showed that 2 of them, RHAMM and AD034, have a differential tissue distribution, and that 3 genes, NAP1L1, RHAMM and AD034, are overexpressed in tumours in comparison with the adjacent non-cancerous tissues. 5' RLM-RACE analysis of AD034, a sequence with a tyrosine kinase mo…
Crosstalk between leukemia-associated proteins MOZ and MLL regulates HOX gene expression in human cord blood CD34+ cells
2010
MOZ and MLL, encoding a histone acetyltransferase (HAT) and a histone methyltransferase, respectively, are targets for recurrent chromosomal translocations found in acute myeloblastic or lymphoblastic leukemia. In MOZ (MOnocytic leukemia Zinc-finger protein)/CBP- or mixed lineage leukemia (MLL)-rearranged leukemias, abnormal levels of HOX transcription factors have been found to be critical for leukemogenesis. We show that MOZ and MLL cooperate to regulate these key genes in human cord blood CD34+ cells. These chromatin-modifying enzymes interact, colocalize and functionally cooperate, and both are recruited to multiple HOX promoters. We also found that WDR5, an adaptor protein essential fo…
Glioblastoma cells induce differential glutamatergic gene expressions in human tumor-associated microglia/macrophages and monocyte-derived macrophages
2015
Glioblastoma cells produce and release high amounts of glutamate into the extracellular milieu and subsequently can trigger seizure in patients. Tumor-associated microglia/macrophages (TAMs), consisting of both parenchymal microglia and monocytes-derived macrophages (MDMs) recruited from the blood, are known to populate up to 1/3 of the glioblastoma tumor environment and exhibit an alternative, tumor-promoting and supporting phenotype. However, it is unknown how TAMs respond to the excess extracellular glutamate in the glioblastoma microenvironment. We investigated the expressions of genes related to glutamate transport and metabolism in human TAMs freshly isolated from glioblastoma resecti…
Novel pathway in Bcr-Abl signal transduction involves Akt-independent, PLC-γ1-driven activation of mTOR/p70S6-kinase pathway
2009
In chronic myeloid leukemia, activation of the phosphoinositide 3-kinase (PI3K)/Akt pathway is crucial for survival and proliferation of leukemic cells. Essential downstream molecules involve mammalian target of rapamycin (mTOR) and S6-kinase. Here, we present a comprehensive analysis of the molecular events involved in activation of these key signaling pathways. We provide evidence for a previously unrecognized phospholipase C-gamma1 (PLC-gamma1)-controlled mechanism of mTOR/p70S6-kinase activation, which operates in parallel to the classical Akt-dependent machinery. Short-term imatinib treatment of Bcr-Abl-positive cells caused dephosphorylation of p70S6-K and S6-protein without inactivat…
Role of two sequence motifs of mesencephalic astrocyte-derived neurotrophic factor in its survival-promoting activity
2015
AbstractMesencephalic astrocyte-derived neurotrophic factor (MANF) is a prosurvival protein that protects the cells when applied intracellularly in vitro or extracellularly in vivo. Its protective mechanisms are poorly known. Here we studied the role of two short sequence motifs within the carboxy-(C) terminal domain of MANF in its neuroprotective activity: the CKGC sequence (a CXXC motif) that could be involved in redox reactions, and the C-terminal RTDL sequence, an endoplasmic reticulum (ER) retention signal. We mutated these motifs and analyzed the antiapoptotic effect and intracellular localization of these mutants of MANF when overexpressed in cultured sympathetic or sensory neurons. …
Intracellular coexpression of CXC- and CC– chemokine receptors and their ligands in human melanoma cell lines and dynamic variations after xenotransp…
2014
Abstract Background Chemokines have been implicated in tumor progression and metastasis. In melanoma, chemokine receptors have been implicated in organ selective metastasis by regulating processes such as chemoattraction, adhesion and survival. Methods In this study we have analyzed, using flow cytometry, the systems formed by the chemokine receptors CXCR3, CXCR4, CXCR7, CCR7 and CCR10 and their ligands in thirteen human melanoma cell lines (five established from primary tumors and eight established from metastasis from different tissues). WM-115 and WM-266.4 melanoma cell lines (obtained from a primary and a metastatic melanoma respectively) were xenografted in nude mice and the tumors and…
IL1β Induces Mesenchymal Stem Cells Migration and Leucocyte Chemotaxis Through NF-κB
2012
Mesenchymal stem cells are often transplanted into inflammatory environments where they are able to survive and modulate host immune responses through a poorly understood mechanism. In this paper we analyzed the responses of MSC to IL-1β: a representative inflammatory mediator. Microarray analysis of MSC treated with IL-1β revealed that this cytokine activateds a set of genes related to biological processes such as cell survival, cell migration, cell adhesion, chemokine production, induction of angiogenesis and modulation of the immune response. Further more detailed analysis by real-time PCR and functional assays revealed that IL-1β mainly increaseds the production of chemokines such as CC…