Optical measurement of membrane potential in cells, organelles, and vesicles.
AuthorsFreedman JC, Novak TS
JournalMethods Enzymol
PubMed ID2747524
Evaluation of single-photon-counting measurements of excited-state lifetimes.
AuthorsZimmerman HE, Penn JH, Carpenter CW,
JournalProc Natl Acad Sci U S A
PubMed ID16593174
An extremely short instrumental response function for a single-photon-counting system has been obtained by using a low-jitter photomultiplier tube, fast amplification of the single photoelectron pulse from this photomultiplier, a constant fraction discriminator with a wide bandwidth input, and a stable reference timing signal. This synchronously mode-locked laser system has ... More
Uptake of fluorescent dyes associated with the functional expression of the cystic fibrosis transmembrane conductance regulator in epithelial cells.
AuthorsWersto RP, Rosenthal ER, Crystal RG, Spring KR
JournalProc Natl Acad Sci U S A
PubMed ID8577734
Specific mutations in the cystic fibrosis transmembrane conductance regulator (CFTR), the most common autosomal recessive fatal genetic disease of Caucasians, result in the loss of epithelial cell adenosine 3',5'-cyclic-monophosphate (cAMP)-stimulated Cl- conductance. We show that the influx of a fluorescent dye, dihydrorhodamine 6G (dR6G), is increased in cells expressing human ... More
Mutual dependence of Foxo3a and PGC-1alpha in the induction of oxidative stress genes.
AuthorsOlmos Y, Valle I, Borniquel S, Tierrez A, Soria E, Lamas S, Monsalve M,
JournalJ Biol Chem
PubMed ID19324885
Oxidative stress is a hallmark of metabolism-related diseases and a risk factor for atherosclerosis. FoxO factors have been shown to play a key role in vascular endothelial development and homeostasis. Foxo3a can protect quiescent cells from oxidative stress through the regulation of detoxification genes such as sod2 and catalase. Here ... More
Kindlin-3 is required for beta2 integrin-mediated leukocyte adhesion to endothelial cells.
AuthorsMoser M, Bauer M, Schmid S, Ruppert R, Schmidt S, Sixt M, Wang HV, Sperandio M, Fässler R,
JournalNat Med
PubMed ID19234461
Integrin activation is essential for the function of all blood cells, including platelets and leukocytes. The blood cell-specific FERM domain protein Kindlin-3 is required for the activation of the beta1 and beta3 integrins on platelets. Impaired activation of beta1, beta2 and beta3 integrins on platelets and leukocytes is the hallmark ... More
Memory landscapes of single-enzyme molecules.
AuthorsEdman L, Rigler R
JournalProc Natl Acad Sci U S A
PubMed ID10880561
Immobilized single horseradish peroxidase enzymes were observed by confocal fluorescence spectroscopy during catalysis of the oxidation reaction of the nonfluorescent dihydrorhodamine 6G substrate into the highly fluorescent product rhodamine 6G. By extracting only the non-Markovian behavior of the spectroscopic two-state process of enzyme-product complex formation and release, memory landscapes were ... More
Fluorescent approach to quantitation of reactive oxygen species in mainstream cigarette smoke.
AuthorsOu B, Huang D
JournalAnal Chem
PubMed ID16642999
A novel approach to monitoring of mainstream smoke reactive oxygen species (ROS) has been developed and applied to the quantitation of smoke oxidants. Redox-active fluorescent probe dihydrorhodamine 6G (DHR-6G) was selected as the molecular probe because it is sensitive to typical smoke ROS. The experimental system couples an automatic cigarette ... More
Fluorescence properties of rhodamine 800 in whole blood and plasma.
AuthorsAbugo OO, Nair R, Lakowicz JR
JournalAnal Biochem
PubMed ID10706783
We have characterized the fluorescence spectral properties of rhodamine 800 (Rh800) in plasma and blood in order to test the possibility of making clinical fluorescence measurements in whole blood without separation steps. Rh800 was used because of its absorption at red/near-infrared wavelengths away from the absorption bands of hemoglobin. We ... More