Search results for "stone"
showing 10 items of 1137 documents
The synergistic effect exerted by the HDAC inhibitor SAHA and the sesquiterpene lactone parthenolide on triple negative breast canc er cells
2014
Triple-negative breast cancer (TNBC) is a subtype o f breast cancer, insensitive to endocrine therapy. Chemotherapy is the main form of treatment, but is accompanied by a high rate of recidivism. The sesquiterpene lactone Parthenolide (PN) exerts a cy totoxic effect on MDA-MB231 cells, a TNBC cell line (1), but was ineffective at low doses (2-5μM). This repr esents an obstacle for a therapeutic utilization of PN. We supposed, in line with other authors (2), that PN c auses a protective response, which at low doses pre vails on the cytotoxic effect. With the aim of inhibiting this protective effect we have shown that pre-trea tment of MDA-MB231 cells with SAHA (2-5μM), an histone deace tylat…
Pre-3000 Ma thermal history of the Archean Kaap Valley puton, South Africa
1992
The Kaap Valley pluton is one of several early Archean (3200-3500 Ma) tonalitetrondhjemite plutons that surround the Barberton Greenstone belt, southern Africa. Precise dating using single-grain 207 Pb/ 206 Pb evaporation of zircon and 40 Ar/ 39 Ar laser step-heating of hornblende and biotite indicates that, in its interior, the Kaap Valley pluton preserves a memory of its initial intrusion and cooling, which spanned a time from 3225 to 3142 Ma. The pluton also records the effect of a low-temperature thermal event at its margin as seen by a 40 Ar/ 39 Ar biotite age of 3035 Ma, which is perhaps related to hydrothermal activity and gold mineralization in the adjacent Barberton Greenstone belt…
Low-energy interactions of Nambu-Goldstone bosons with D mesons in covariant chiral perturbation theory
2010
We calculate the scattering lengths of Nambu-Goldstone bosons interacting with D mesons in a covariant formulation of chiral perturbation theory, which satisfies heavy-quark spin symmetry and analytical properties of loop amplitudes. We compare our results with previous studies performed using heavy-meson chiral perturbation theory and show that recoil corrections are sizable in most cases.
IL-10 down-regulates T cell activation by antigen-presenting liver sinusoidal endothelial cells through decreased antigen uptake via the mannose rece…
1998
SUMMARYOur study demonstrates that antigen-presenting liver sinusoidal endothelial cells (LSEC) induce production of interferon-gamma (IFN-γ) from cloned Th1 CD4+ T cells. We show that LSEC used the mannose receptor for antigen uptake, which further strengthened the role of LSEC as antigen-presenting cell (APC) population in the liver. The ability of LSEC to activate cloned CD4+ T cells antigen-specifically was down-regulated by exogenous prostaglandin E2 (PGE2) and by IL-10. We identify two separate mechanisms by which IL-10 down-regulated T cell activation through LSEC. IL-10 decreased the constitutive surface expression of MHC class II as well as of the accessory molecules CD80 and CD86 …
Paracrine in vivo inhibitory effects of adipose tissue–derived mesenchymal stromal cells in the early stages of the acute inflammatory response
2015
Abstract Background aims Excessive or unresolved inflammation leads to tissue lesions. Adipose tissue–derived mesenchymal stromal cells (AMSCs) have shown protective effects that may be dependent on the modulation of inflammation by secreted factors. Methods We used the zymosan-induced mouse air pouch model at two time points (4 h and 18 h) to evaluate the in vivo effects of AMSCs and their conditioned medium (CM) on key steps of the early inflammatory response. We assessed the effects of AMSCs and CM on leukocyte migration and myeloperoxidase activity. The levels of chemokines, cytokines and eicosanoids in exudates were measured by use of enzyme-linked immunoassay or radio-immunoassay. In …
Redox regulation of genome stability by effects on gene expression, epigenetic pathways and DNA damage/repair
2015
Reactive oxygen and nitrogen species (e.g. H2O2, nitric oxide) confer redox regulation of essential cellular signaling pathways such as cell differentiation, proliferation, migration and apoptosis. In addition, classical regulation of gene expression or activity, including gene transcription to RNA followed by translation to the protein level, by transcription factors (e.g. NF-κB, HIF-1α) and mRNA binding proteins (e.g. GAPDH, HuR) is subject to redox regulation. This review will give an update of recent discoveries in this field, and specifically highlight the impact of reactive oxygen and nitrogen species on DNA repair systems that contribute to genomic stability. Emphasis will be placed …
Nordic contemporary art education and the environment: Constructing an epistemological platform for Art Education for Sustainable Development (AESD)
2012
How can art educators address questions of environmental sustainability, accepting to be ethically normative but avoiding becoming dogmatic? How can the complex ‘pool’ of knowledge generated in and through art education research become useful in working with these questions, which many of us find overwhelmingly difficult? AESD – Art Education for Sustainable Development – is a concept coined for this article with the intention of bringing environmental problems onto the agenda. In an attempt to provoke the necessary discussion about environmental sustainability in art education, the article examines selected texts from recent Nordic research in order to build an ‘epistemological platform’ t…
Juvenile ossifying fibroma of the maxillofacial region: analysis of clinico-pathological features and management
2021
Background The diagnosis and management of juvenile ossifying fibroma (JOF) remains a highly debated topic with paucity of studies with long-term follow-up, hence the aim of this study was to report on the clinico-pathological features and management of these neoplasms. Material and Methods A retrospective analysis was performed on all histopathologically confirmed JOF presenting at two tertiary hospitals in Cape Town, South Africa over a period of 39 years. Clinical, demographic, histopathological and radiological features were analyzed. Surgical methods were documented and a minimum post-operative follow-up of 12 months was a prerequisite. Results Seventeen patients met the inclusion crit…
Alignment Free Dissimilarities for Nucleosome Classification
2016
Epigenetic mechanisms such as nucleosome positioning, histone modifications and DNA methylation play an important role in the regulation of cell type-specific gene activities, yet how epigenetic patterns are established and maintained remains poorly understood. Recent studies have shown a role of DNA sequences in recruitment of epigenetic regulators. For this reason, the use of more suitable similarities or dissimilarity between DNA sequences could help in the context of epigenetic studies. In particular, alignment-free dissimilarities have already been successfully applied to identify distinct sequence features that are associated with epigenetic patterns and to predict epigenomic profiles…
CRISPR-Cas9 screen reveals a MYCN-amplified neuroblastoma dependency on EZH2.
2018
Pharmacologically difficult targets, such as MYC transcription factors, represent a major challenge in cancer therapy. For the childhood cancer neuroblastoma, amplification of the oncogene MYCN is associated with high-risk disease and poor prognosis. Here, we deployed genome-scale CRISPR-Cas9 screening of MYCN-amplified neuroblastoma and found a preferential dependency on genes encoding the polycomb repressive complex 2 (PRC2) components EZH2, EED, and SUZ12. Genetic and pharmacological suppression of EZH2 inhibited neuroblastoma growth in vitro and in vivo. Moreover, compared with neuroblastomas without MYCN amplification, MYCN-amplified neuroblastomas expressed higher levels of EZH2. ChIP…