Search results for " ACTIVATION"
showing 10 items of 1535 documents
The endopolygalacturonase 1 from botrytis cinerea activates grapevine defense reactions unrelated to its enzyumatic activity
2003
A purified glycoprotein from Botrytis cinerea(strain T4), identified as endopolygalacturonase 1 (T4BcPG1) by mass spectrometry analysis, has been shown to activate defense reactions in grapevine (Vitis vinifera cv. Gamay). These reactions include calcium influx, production of active oxygen species, activation of two mitogen-activated protein kinases, defense gene transcript accumulation, and phytoalexin production. Most of these defense reactions were also activated in grapevine in response to purified oligogalacturonides (OGA) with a degree of polymerization of 9 to 20. In vivo, these active OGA might be a part of the released products resulting from endopolygalacturonase activity on plan…
Extensive nuclear gyration and pervasive non-genic transcription during primordial germ cell development in zebrafish.
2020
ABSTRACT Primordial germ cells (PGCs) are the precursors of germ cells, which migrate to the genital ridge during early development. Relatively little is known about PGCs after their migration. We studied this post-migratory stage using microscopy and sequencing techniques, and found that many PGC-specific genes, including genes known to induce PGC fate in the mouse, are only activated several days after migration. At this same time point, PGC nuclei become extremely gyrated, displaying general broad opening of chromatin and high levels of intergenic transcription. This is accompanied by changes in nuage morphology, expression of large loci (PGC-expressed non-coding RNA loci, PERLs) that ar…
Effect of digitonin on membrane-bound and chitosomal chitin synthetase activity in protoplasts from yeast cells ofCandida albicans
1993
The effect of digitonin on chitin synthetase present in membrane (MMF) and cytoplasmic fractions (chitosomes) (CF) from C. albicans yeast protoplasts has been determined. The zymogen is preferentially, but not exclusively, solubilized by digitonin from MMF. Centrifugation of distinct solubilized preparations, containing either zymogen, in vivo active enzyme and/or trypsin activated enzyme, on linear sucrose gradients suggests that both zymogen and trypsin activated enzyme sediment slightly slower than the active enzyme, pointing out differences between the activation processes in vivo and in vitro or, alternatively, that both enzyme activities (active in vivo and zymogenic) correspond to di…
New Frontiers in Cancer Imaging and Therapy Based on Radiolabeled Fibroblast Activation Protein Inhibitors: A Rational Review and Current Progress.
2021
Over the past decade, the tumor microenvironment (TME) has become a new paradigm of cancer diagnosis and therapy due to its unique biological features, mainly the interconnection between cancer and stromal cells. Within the TME, cancer-associated fibroblasts (CAFs) demonstrate as one of the most critical stromal cells that regulate tumor cell growth, progression, immunosuppression, and metastasis. CAFs are identified by various biomarkers that are expressed on their surfaces, such as fibroblast activation protein (FAP), which could be utilized as a useful target for diagnostic imaging and treatment. One of the advantages of targeting FAP-expressing CAFs is the absence of FAP expression in q…
Hydrogen activation with perfluorinated organoboranes: 1,2,3- tris(pentafluorophenyl)-4,5,6,7-tetrafluoro-1-boraindene
2014
The perfluorinated boraindene 3 was synthesized and fully characterized. Both computational and crystallographic data show that 3 is antiaromatic. Compound 3 was shown to react reversibly with H2 and to catalyse the hydrogenation of cyclohexene. The mechanism of catalysis was probed experimentally and computationally. peerReviewed
Fruits and vegetables protect against the genotoxicity of heterocyclic aromatic amines activated by human xenobiotic-metabolizing enzymes expressed i…
2010
Heterocyclic aromatic amines (HAAs) can be formed during the cooking of meat and fish at elevated temperatures and are associated with an increased risk for cancer. On the other hand, epidemiological findings suggest that foods rich in fruits and vegetables can protect against cancer. In the present study three teas, two wines, and the juices of 15 fruits and 11 vegetables were investigated for their protective effect against the genotoxic effects of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). To closely mimic the enzymatic activation of these HAAs in humans, genetically engineered V79 Chinese hamster fibroblasts were employed tha…
V gamma 9V delta 2 T lymphocytes efficiently recognize and kill zoledronate-sensitized, imatinib-sensitive, and imatinib-resistant chronic myelogenou…
2010
Abstract Imatinib mesylate (imatinib), a competitive inhibitor of the BCR-ABL tyrosine kinase, is highly effective against chronic myelogenous leukemia (CML) cells. However, because 20–30% of patients affected by CML display either primary or secondary resistance to imatinib, intentional activation of Vγ9Vδ2 T cells by phosphoantigens or by agents that cause their accumulation within cells, such as zoledronate, may represent a promising strategy for the design of a novel and highly innovative immunotherapy capable to overcome imatinib resistance. In this study, we show that Vγ9Vδ2 T lymphocytes recognize, trogocytose, and efficiently kill imatinib-sensitive and -resistant CML cell lines pre…
Iron-Catalyzed C–O Bond Activation: Opportunity for Sustainable Catalysis
2017
Oxygen-based electrophiles have emerged as some of the most valuable cross-coupling partners in organic synthesis due to several major strategic and environmental benefits such as abundance and potential to avoid toxic halide waste. In this context, iron-catalyzed C–O activation/cross-coupling holds particular promise to achieve sustainable catalytic protocols due to its natural abundance, inherent low toxicity, an excellent economic and ecological profile. Recently, tremendous progress has been achieved in the development of new methods for functional group tolerant iron-catalyzed cross-coupling reactions by selective C–O cleavage. These methods establish highly attractive alternatives to …
Sex-Specific Relationship Between Parathyroid Hormone and Platelet Indices in Phenotypes of Heart Failure—Results From the MyoVasc Study
2021
Background: Heart failure (HF) is a multifactorial syndrome with pathophysiological complexities still not fully understood. Higher mean platelet volume (MPV), a potential marker of platelet activation, and high concentrations of parathyroid hormone (PTH) have been implicated in the pathogenesis of HF.Aim: This study aims to investigate sex-specifically the association between PTH concentrations and platelet indices in phenotypes of HF.Methods and Results: PTH and platelet indices (MPV and platelet count) were available in 1,896 participants from the MyoVasc study in Mainz, Germany. Multivariable linear regression models, adjusted for age, sex, season, vitamin D status, cardiovascular risk …
Catalytic effect of transition metals (copper, iron, and nickel) on the foaming and properties of sugar-based carbon foams
2019
Abstract Recently, bio-based carbon foams have gained much interest in many chemical industry fields because of their unique structure and properties. This study provides new information on the effects of catalytic metals (iron, nickel, and copper) on the foaming process. Specifically, the effects of these catalysts on the density, foam growth, and cell size and then further on the pore size distribution and specific surface areas after the physical activation are considered. Furthermore, some of the activated sugar foams were used in adsorption tests using methylene blue as adsorbent. Results showed that the highest effect on foam density was obtained using the iron catalyst in the foaming…