Search results for "RESISTANCE"
showing 10 items of 3641 documents
The Consumer Resistance Behavior towards Innovation
2013
Abstract The purpose of this work is to identify and analyze consumer resistance in order to understand this concept in the area of resistant behavior. The paper converges on studying the resistance to innovation from a theoretical perspective and to show it importance in innovation process. The paper concludes bydescribing the complexity of resistance to innovation, its forms and effects on the behavior of consumers and market. Although most authors focus their research on positive adoption decisions, this paper instead focus on developing insight into the relatively underdeveloped area of resistant behavior literature by presenting key concepts of resistance to innovation.
Fate of the herbicides glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron in two Finnish arable soils.
2006
The fate of five herbicides (glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron) was studied in two Finnish sugar beet fields for 26 months. Soil types were sandy loam and clay. Two different herbicide-tolerant sugar beet cultivars and three different herbicide application schedules were used. Meteorological data were collected throughout the study and soil properties were thoroughly analysed. An extensive data set of herbicide residue concentrations in soil was collected. Five different soil depths were sampled. The study was carried out using common Finnish agricultural practices and represents typical sugar beet cultivation conditions in Finland. The overall obse…
Biochemistry and genetics of insect resistance to Bacillus thuringiensis.
2001
▪ Abstract Bacillus thuringiensis (Bt) is a valuable source of insecticidal proteins for use in conventional sprayable formulations and in transgenic crops, and it is the most promising alternative to synthetic insecticides. However, evolution of resistance in insect populations is a serious threat to this technology. So far, only one insect species has evolved significant levels of resistance in the field, but laboratory selection experiments have shown the high potential of other species to evolve resistance against Bt. We have reviewed the current knowledge on the biochemical mechanisms and genetics of resistance to Bt products and insecticidal crystal proteins. The understanding of th…
Survival of two strains of Phthorimaea operculella (Lepidoptera: Gelechiidae) reared on transgenic potatoes expressing a Bacillus thuringiensis cryst…
1998
[Otros] Survie de deux souches de Phthorimaea operculella (Lepidoptera : Gelechiidae) élevées sur des pommes de terre transgéniques exprimant la protéine CrylAb de Bacillus thuringiensis. Deux populations de Phthorimaea operculella (Zeller), l'une supposée résistante au DipelTM (une préparation commerciale de delta-endotoxines de Bacillus thuringiensis) et l'autre sensible, ont été cultivées sur quatre cultivars de pomme de terre, deux transgéniques de première génération, exprimant la protéine CrylAb de Bacillus thuringiensis, et deux non transformés. La population de papillons considérée comme résistante a présenté une mortalité inférieure à celle de l'autre population, mais n'était pas v…
Bacteriophage Resistance Affects Flavobacterium columnare Virulence Partly via Mutations in Genes Related to Gliding Motility and the Type IX Secreti…
2021
Increasing problems with antibiotic resistance have directed interest toward phage therapy in the aquaculture industry. However, phage resistance evolving in target bacteria is considered a challenge. To investigate how phage resistance influences the fish pathogen Flavobacterium columnare, two wild-type bacterial isolates, FCO-F2 and FCO-F9, were exposed to phages (FCO-F2 to FCOV-F2, FCOV-F5, and FCOV-F25, and FCO-F9 to FCL-2, FCOV-F13, and FCOV-F45), and resulting phenotypic and genetic changes in bacteria were analyzed. Bacterial viability first decreased in the exposure cultures but started to increase after 1 to 2 days, along with a change in colony morphology from original rhizoid to …
Activity of three cytotoxic isoflavonoids from Erythrina excelsa and Erythrina senegalensis (neobavaisoflavone, sigmoidin H and isoneorautenol) towar…
2013
Abstract Introduction Resistance of cancer cells to chemotherapy has become a worldwide concern. Naturally occuring isoflavonoids possess a variety of biological activities including anti-cancer effects. The present study was aimed at investigating the cytotoxicity and the modes of action of three naturally occuring isoflavonoids, neobavaisoflavone ( 1 ), sigmoidin H ( 2 ) and a pterocarpan that is a special type of isoflavonoid, isoneorautenol ( 3 ) against a panel of nine cancer cell lines, including various sensitive and drug-resistant phenotypes. Methods The cytotoxicity of the compounds was determined using a resazurin reduction assay, whereas the caspase-Glo assay was used to detect t…
Cytotoxicity of a naturally occurring furoquinoline alkaloid and four acridone alkaloids towards multi-factorial drug-resistant cancer cells
2015
Abstract Introduction Chemotherapy is one of the preferred mode of treatment of malignancies, but is complicated by the expression of diverse resistance mechanisms of cancer cells. Methods In the present study, we investigated the cytotoxicity of five alkaloids including a furoquinoline montrofoline (1) and four acridones namely 1-hydroxy-4-methoxy-10-methylacridone (2), norevoxanthine (3), evoxanthine (4), 1,3-dimethoxy-10-methylacridone (5) against 9 drug-sensitive and multidrug-resistant (MDR) cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these compounds, whilst caspase-Glo assay was used to detect caspase activation. Cell cycle, mitochondrial …
Cytotoxicity of isoflavones and biflavonoids from Ormocarpum kirkii towards multi-factorial drug resistant cancer.
2019
Abstract Background While incidences of cancer are continuously increasing, drug resistance of malignant cells is observed towards almost all pharmaceuticals. Several isoflavonoids and flavonoids are known for their cytotoxicity towards various cancer cells. Purpose The aim of this study was to determine the cytotoxicity of isoflavones: osajin (1), 5,7-dihydroxy-4ˈ-methoxy-6,8-diprenylisoflavone (2) and biflavonoids: chamaejasmin (3), 7,7″-di-O-methylchamaejasmin (4) and campylospermone A (5), a dimeric chromene [diphysin(6)] and an ester of ferullic acid with long alkyl chain [erythrinasinate (7)] isolated from the stem bark and roots of the Kenyan medicinal plant, Ormocarpum kirkii. The m…
Resveratrol mediated cancer cell apoptosis, and modulation of multidrug resistance proteins and metabolic enzymes.
2019
Abstract Background The degree of intracellular drug accumulation by specific membrane transporters, i.e., MDR1, BCRP, and MRP, and the degree of detoxification by intracellular metabolic enzymes, i.e., CYP3A4 and GST, provide control for cancer chemotherapy through diminishing the propensity of cancer cells to undergo apoptosis which in turn modulates the unresolved and complex phenomenon of multidrug resistance (MDR) for the cancer cells. Hypothesis/Purpose This study dwells into the interaction details involving ABC-transporters, CYP3A4, GST and cytotoxic effects of resveratrol on different cell lines. Methods Resveratrol was evaluated for its ability modulating the expression and efflux…
Cytotoxic Compounds from the Fruits of Uapaca togoensis towards Multifactorial Drug-Resistant Cancer Cells
2014
Cancer cells may rapidly acquire multidrug resistance, mainly due to the presence of adenosine triphosphate-binding cassette transporters, epidermal growth factor receptor, or mutations in the p53 tumor suppressor gene. This work was designed to assess the cytotoxicity of the methanol crude extracts and compounds from the fruits of Uapaca togoensis, namely, β-amyryl acetate (1), 11-oxo-α-amyryl acetate (2), lupeol (3), pomolic acid (4), futokadsurin B (5), arborinin (6), and 3-O-β-D-glucopyranosyl sitosterol (7) against nine drug sensitive and multidrug-resistant cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of the fruits of U. togoensis and compound…