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621.
Helen E. Gruber Shirley S. Coleman Audrey A. Stasky Gretchen L. Hoelscher Bhaloo J. Desai 《Biotechnic & histochemistry》1999,74(3):141-145
This technical report presents a practical experimental protocol using human fibroblasts that is useful for initiating in situ methods for detection of apoptotic cells in vitro. The protocol details the growth of cells in multichamber wells, and includes a negative control, two positive controls, and untreated fibroblasts to be evaluated for apoptosis localization. Technical tips on handling of solutions, cell culture designs, and separation of slides by treatment are valuable steps for the laboratory beginning such studies. The methods proposed are both time and cost effective. 相似文献
622.
A fluoride-resistant Streptococcus mutans isolate NCH105 was characterized and compared with wild-type strain UA130. The growth and lactic acid production of strain
NCH105 were found to be unaffected by the presence of fluoride at the initial medium pH values of 6.5 and 6. In addition,
NCH105 was found to be capable of lowering the pH of the medium to approximately 5.5, which is the critical level where enamel
demineralization begins in vivo. Lactic acid production, glucose uptake at pH 6.5 and 6, as well as ATPase activity at pH
5 were found to be unaffected by fluoride. Finally, strain NCH105 is capable of binding as well as the wild-type bacterium
to artificial tooth pellicles. These results are unusual when compared with previously isolated fluoride-resistant mutants
and suggest that NCH105 may have the ability to colonize the tooth surface and initiate dental caries. 相似文献
623.
Gretchen McCaffrey Jonathan Welker Jessica Scott Louise van der Salm Mark L. Grimes 《Traffic (Copenhagen, Denmark)》2009,10(7):938-950
Receptor endocytosis is regulated by ligand binding, and receptors may signal after endocytosis in signaling endosomes. We hypothesized that signaling endosomes containing different types of receptors may be distinct from one another and have different physical characteristics. To test this hypothesis, we developed a high-resolution organelle fractionation method based on mass and density, optimized to resolve endosomes from other organelles. Three different types of receptors undergoing ligand-induced endocytosis were localized predominately in endosomes that were resolved from one another using this method. Endosomes containing activated receptor tyrosine kinases (RTKs), TrkA and EGFR, were similar to one another. Endosomes containing p75NTR (in the tumor necrosis receptor superfamily) and PAC1 (a G-protein-coupled receptor) were distinct from each other and from RTK endosomes. Receptor-specific endosomes may direct the intracellular location and duration of signal transduction pathways to dictate response to signals and determine cell fate. 相似文献
624.
Andrew F. Donnell Yong Zhang Erik M. Stang Donna D. Wei Andrew J. Tebben Heidi L. Perez Gretchen M. Schroeder Chin Pan Chetana Rao Robert M. Borzilleri Gregory D. Vite Sanjeev Gangwar 《Bioorganic & medicinal chemistry letters》2017,27(23):5267-5271
Macrocyclic pyrrolobenzodiazepine dimers were designed and evaluated for use as antibody-drug conjugate payloads. Initial structure–activity exploration established that macrocyclization could increase the potency of PBD dimers compared with non-macrocyclic analogs. Further optimization overcame activity-limiting solubility issues, leading to compounds with highly potent (picomolar) activity against several cancer cell lines. High levels of in vitro potency and specificity were demonstrated with an anti-mesothelin conjugate. 相似文献
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