Search results for "sun"
showing 10 items of 935 documents
The Second Flight of the Sunrise Balloon-borne Solar Observatory: Overview of Instrument Updates, the Flight, the Data, and First Results
2017
S. K. Solanki et. al.
La motte médiévale de Drosnay (Marne) : résultats de deux sondages archéologiques
2011
Deux opérations de diagnostic réalisées en 2008 et 2009 ont permis de mettre au jour un segment du fossé d’enceinte d’une motte répertoriée depuis le XIXe s., ainsi que les restes d’un bâtiment en pierre sur sa partie sommitale. Le fossé a livré un mobilier dont la chronologie est centrée sur le XIIIe s. alors que le bâtiment n’est pas antérieur au XVe s. Les remaniements ayant affecté ce site sont nombreux. Dès le XVe s. d’importants travaux de remblaiement et de nivellement semblent modifier l’angle sud-ouest de la motte. Cependant, ce sont les terrassements contemporains qui ont irrémédiablement détruit la plus grande part des vestiges. Seule la basse-cour peut désormais conserver des ve…
¿Un ministro para la esperanza? / y 2
2004
Artesunate derived from traditional Chinese medicine induces DNA damage and repair.
2008
Abstract Artesunate is a semisynthetic derivative from artemisinin, a natural product from the Chinese herb Artemisia annua L. It exerts antimalarial activity, and, additionally, artemisinin and its derivatives are active against cancer cells. The active moiety is an endoperoxide bridge. Its cleavage leads to the formation of reactive oxygen species and carbon-centered radicals. These highly reactive molecules target several proteins in Plasmodia, which is thought to result in killing of the microorganism. DNA damage induced by artemisinins has not yet been described. Here, we show that artesunate induces apoptosis and necrosis. It also induces DNA breakage in a dose-dependent manner as sho…
Development of resistance towards artesunate in MDA-MB-231 human breast cancer cells.
2011
Breast cancer is the most common cancer and the second leading cause of cancer death in industrialized countries. Systemic treatment of breast cancer is effective at the beginning of therapy. However, after a variable period of time, progression occurs due to therapy resistance. Artesunate, clinically used as anti-malarial agent, has recently revealed remarkable anti-tumor activity offering a role as novel candidate for cancer chemotherapy. We analyzed the anti-tumor effects of artesunate in metastasizing breast carcinoma in vitro and in vivo. Unlike as expected, artesunate induced resistance in highly metastatic human breast cancer cells MDA-MB-231. Likewise acquired resistance led to abol…
Artesunate induces oxidative DNA damage, sustained DNA double-strand breaks, and the ATM/ATR damage response in cancer cells.
2011
Abstract Artesunate, the active agent from Artemisia annua L. used in the traditional Chinese medicine, is being applied as a first-line drug for malaria treatment, and trials are ongoing that include this drug in cancer therapy. Despite increasing interest in its therapeutic application, the mode of cell killing provoked by artesunate in human cells is unknown. Here, we show that artesunate is a powerful inducer of oxidative DNA damage, giving rise to formamidopyrimidine DNA glycosylase–sensitive sites and the formation of 8-oxoguanine and 1,N6-ethenoadenine. Oxidative DNA damage was induced in LN-229 human glioblastoma cells dose dependently and was paralleled by cell death executed by ap…
Novel chromosome copy number changes to predict clinical response to sunitinib in patients with advanced renal cell carcinoma
2015
4552 Background: Sunitinib is a 1st-line therapy for clear cell Renal Cell Carcinoma (ccRCC); however, 20-30% of tumors show primary resistant disease (PRD) with progression as the best response. T...
Analysis of Antiproliferative and Chemosensitizing Effects of Sunitinib on Human Esophagogastric Cancer Cells: Synergistic Interaction With Vandetani…
2009
The receptor tyrosine kinases (RTKs), epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor 1-3 (VEGFR1-3), are frequently expressed in gastric cancer and are putative therapeutic targets in this disease. We have investigated the anti-proliferative and chemosensitizing properties of the multitargeted small-molecule RTK inhibitors sunitinib and vandetanib in a panel of 4 human gastric and esophageal cancer cell lines. In the 1st instance, the expression of potential targets of these small-molecule inhibitors was examined by reverse transcriptase-polymerase chain reaction, western blotting, and flow cytometry. EGFR mRNA and protein was detected in all cases, …
Sun exposure and malignant lymphoma: A population-based case–control study in Germany
2007
Although some causes for malignant lymphoma are known their etiology is not well understood so far. We analyze the relationship between sun exposure and malignant lymphoma in a multicenter, population-based case-control study. Patients with malignant lymphoma (n = 710, 18-80 years) were prospectively recruited in 6 study regions in Germany. For each case, a gender, region and age-matched control was drawn from population-registers. In personal interviews, lifetime holidays spent in sunny climate, outdoor leisure activities and sunbed or sunlamp use were recorded. On basis of job task-specific supplementary questionnaires, an occupational physician assessed the cumulative working time outsid…
Factors determining sensitivity or resistance of tumor cell lines towards artesunate.
2009
Clinical oncology is still challenged by the development of drug resistance of tumors that result in poor prognosis for patients. There is an urgent necessity to understand the molecular mechanisms of resistance and to develop novel therapy strategies. Artesunate (ART) is an anti-malarial drug, which also exerts profound cytotoxic activity towards cancer cells. We first applied a gene-hunting approach using cluster and COMPARE analyses of microarray-based transcriptome-wide mRNA expression profiles. Among the genes identified by this approach were genes from diverse functional groups such as structural constituents of ribosomes (RPL6, RPL7, RPS12, RPS15A), kinases (CABC1, CCT2, RPL41), tran…