Visualization of cell surface vasopressin V1a receptors in rat hepatocytes with a fluorescent linear antagonist.
AuthorsTran D, Durroux T, Stelly N, Seyer R, Tordjmann T, Combettes L, Claret M
JournalJ Histochem Cytochem
PubMed ID10026242
To visualize cell surface V1a vasopressin receptors in rat hepatocytes in the absence of receptor-mediated endocytosis, we used a high-affinity fluorescent linear antagonist, Rhm8-PVA. Epifluorescence microscopy (3CCD camera) and fluorescence spectroscopy were used. Rhm8-PVA alone did not stimulate Ca2+ signals and competitively blocked Ca2+ signals (Kinact of 3.0 nM) evoked ... More
IGF-1 overexpression inhibits the development of diabetic cardiomyopathy and angiotensin II-mediated oxidative stress.
AuthorsKajstura J, Fiordaliso F, Andreoli AM, Li B, Chimenti S, Medow MS, Limana F, Nadal-Ginard B, Leri A, Anversa P
JournalDiabetes
PubMed ID11375343
'Stimulation of the local renin-angiotensin system and apoptosis characterize the diabetic heart. Because IGF-1 reduces angiotensin (Ang) II and apoptosis, we tested whether streptozotocin-induced diabetic cardiomyopathy was attenuated in IGF-1 transgenic mice (TGM). Diabetes progressively depressed ventricular performance in wild-type mice (WTM) but had no hemodynamic effect on TGM. Myocyte ... More
Determination of intracellular organelles implicated in daunorubicin cytoplasmic sequestration in multidrug-resistant MCF-7 cells using fluorescence microscopy image analysis.
AuthorsBour-Dill C, Gramain MP, Merlin JL, Marchal S, Guillemin F
JournalCytometry
PubMed ID10655559
'BACKGROUND: Anthracycline resistance is known to be mediated by P-glycoprotein (P-gp) or multidrug-resistance related protein (MRP) as well as intracellular sequestration of drugs. METHODS: The resistance phenotype of doxorubicin-selected MCF-7(DXR) human breast adenocarcinoma cell line was characterized by cellular and nuclear daunorubicin efflux, P-gp and MRP expression and apoptosis induction. ... More
Intensity calibration and automated cell cycle gating for high-throughput image-based siRNA screens of mammalian cells.
AuthorsPoon SS, Wong JT, Saunders DN, Ma QC, McKinney S, Fee J, Aparicio SA,
JournalCytometry A
PubMed ID18698634
'High-content microscopic screening systems are powerful tools for extracting quantitative multiparameter measures from large number of cells under numerous conditions. These systems perform well in applications that monitor the presence of objects, but lack in their ability to accurately estimate object intensities and summarize these findings due to variations in ... More
Prediction and measurement of an autoregulatory genetic module.
AuthorsIsaacs FJ, Hasty J, Cantor CR, Collins JJ
JournalProc Natl Acad Sci U S A
PubMed ID12808135
'The deduction of phenotypic cellular responses from the structure and behavior of complex gene regulatory networks is one of the defining challenges of systems biology. This goal will require a quantitative understanding of the modular components that constitute such networks. We pursued an integrated approach, combining theory and experiment, to ... More
Substance P released from intrinsic airway neurons contributes to ozone-enhanced airway hyperresponsiveness in ferret trachea.
AuthorsWu ZX, Satterfield BE, Dey RD
JournalJ Appl Physiol
PubMed ID12730146
'Exposure to ozone (O3) induces airway hyperresponsiveness mediated partly through the release of substance P (SP) from nerve terminals in the airway wall. Although substantial evidence suggests that SP is released by sensory nerves, SP is also present in neurons of airway ganglia. The purpose of this study was to ... More
Neural agrin controls acetylcholine receptor stability in skeletal muscle fibers.
'At mammalian neuromuscular junctions (NMJs), innervation induces and maintains the metabolic stability of acetylcholine receptors (AChRs). To explore whether neural agrin may cause similar receptor stabilization, we injected neural agrin cDNA of increasing transfection efficiencies into denervated adult rat soleus (SOL) muscles. As the efficiency increased, the amount of recombinant ... More
Interleukin-1beta-induced airway hyperresponsiveness enhances substance P in intrinsic neurons of ferret airway.
AuthorsWu ZX, Satterfield BE, Fedan JS, Dey RD
JournalAm J Physiol Lung Cell Mol Physiol
PubMed ID12376343
'Interleukin (IL)-1beta causes airway inflammation, enhances airway smooth muscle responsiveness, and alters neurotransmitter expression in sensory, sympathetic, and myenteric neurons. This study examines the role of intrinsic airway neurons in airway hyperresponsiveness (AHR) induced by IL-1beta. Ferrets were instilled intratracheally with IL-1beta (0.3 microg/0.3 ml) or saline (0.3 ml) once ... More
Image cytometric method for quantifying the relative amount of DNA in bacterial nucleoids using Escherichia coli.
AuthorsVischer NO, Huls PG, Ghauharali RI, Brakenhoff GJ, Nanninga N, Woldringh CL
JournalJ Microsc
PubMed ID10540258
'An image cytometric method for quantifying integrated fluorescence was developed to measure the relative DNA contents of bacterial nucleoids. Image analysis was performed with newly developed macros in combination with the program Object-Image, all downloadable from http://simon.bio.uva.nl/object-image.html. Four aspects of the method were investigated. (i) Good linearity was found over ... More
INTRODUCTION: In previous studies we and others have demonstrated the usefulness of violet laser diodes (VLDs) as replacement laser sources for krypton-ion lasers on stream-in-air cytometers. Previously available VLDs had a maximum available power of less than 25 mW; this was sufficient for excitation of densely labeled cell surface antigens ... More
Direct gene transfer into rat articular cartilage by in vivo electroporation.
AuthorsGrossin L, Cournil-Henrionnet C, Mir LM, Liagre B, Dumas D, Etienne S, Guingamp C, Netter P, Gillet P
JournalFASEB J
PubMed ID12724342
To establish a system for efficient direct in vivo gene targeting into rat joint, we have evaluated a strategy of gene transfer by means of the delivery of external electric pulses (EP) to the knee after intra-articular injection of a reporter gene (GFP). Rats were killed at various times after ... More
Role of intrinsic airway neurons in ozone-induced airway hyperresponsiveness in ferret trachea.
Exposure to ozone (O(3)) enhances airway responsiveness, which is mediated partly by the release of substance P (SP) from airway neurons. In this study, the role of intrinsic airway neurons in O(3)-induced airway responses was examined. Ferrets were exposed to 2 ppm O(3) or air for 1 h. Reactivity of ... More
Effects of purified recombinant neural and muscle agrin on skeletal muscle fibers in vivo.
AuthorsBezakova G, Helm JP, Francolini M, Lømo T
JournalJ Cell Biol
PubMed ID11425874
Aggregation of acetylcholine receptors (AChRs) in muscle fibers by nerve-derived agrin plays a key role in the formation of neuromuscular junctions. So far, the effects of agrin on muscle fibers have been studied in culture systems, transgenic animals, and in animals injected with agrin--cDNA constructs. We have applied purified recombinant ... More
Video-rate nonlinear microscopy of neuronal membrane dynamics with genetically encoded probes.
AuthorsRoorda RD, Hohl TM, Toledo-Crow R, Miesenböck G
JournalJ Neurophysiol
PubMed ID14999051
Biological membranes decorated with suitable contrast agents give rise to nonlinear optical signals such as two-photon fluorescence and harmonic up-conversion when illuminated with ultra-short, high-intensity pulses of infrared laser light. Microscopic images based on these nonlinear contrasts were acquired at video or higher frame rates by scanning a focused illuminating ... More
Serum from patients with type 2 diabetes with neuropathy induces complement-independent, calcium-dependent apoptosis in cultured neuronal cells.
AuthorsSrinivasan S, Stevens MJ, Sheng H, Hall KE, Wiley JW
JournalJ Clin Invest
PubMed ID9769338
We hypothesized that sera from type 2 diabetic patients with neuropathy contains an autoimmune immunoglobulin that promotes complement-independent, calcium-dependent apoptosis in neuronal cell lines. Neuronal cells were cultured in the presence of complement-inactivated sera obtained from patients with type 2 diabetes with and without neuropathy and healthy adult control patients. ... More
Metallothionein prevents diabetes-induced deficits in cardiomyocytes by inhibiting reactive oxygen species production.
AuthorsYe G, Metreveli NS, Ren J, Epstein PN
JournalDiabetes
PubMed ID12606520
Many individuals with diabetes experience impaired cardiac contractility that cannot be explained by hypertension and atherosclerosis. This cardiomyopathy may be due to either organ-based damage, such as fibrosis, or to direct damage to cardiomyocytes. Reactive oxygen species (ROS) have been proposed to contribute to such damage. To address these hypotheses, ... More
Regulation of epithelial Na(+) channels by actin in planar lipid bilayers and in the Xenopus oocyte expression system.
AuthorsJovov B, Tousson A, Ji HL, Keeton D, Shlyonsky V, Ripoll PJ, Fuller CM, Benos DJ
JournalJ Biol Chem
PubMed ID10608849
The hypothesis that actin interactions account for the signature biophysical properties of cloned epithelial Na(+) channels (ENaC) (conductance, ion selectivity, and long mean open and closed times) was tested using planar lipid bilayer reconstitution and patch clamp techniques. We found the following. 1) In bilayers, actin produced a more than ... More
Performance comparison between the high-speed Yokogawa spinning disc confocal system and single-point scanning confocal systems.
AuthorsWang E, Babbey CM, Dunn KW
JournalJ Microsc
PubMed ID15857376
Fluorescence microscopy of the dynamics of living cells presents a special challenge to a microscope imaging system, simultaneously requiring both high spatial resolution and high temporal resolution, but with illumination levels low enough to prevent fluorophore damage and cytotoxicity. We have compared the high-speed Yokogawa CSU10 spinning disc confocal system ... More
Calcium influx through calcium leak channels is responsible for the elevated levels of calcium-dependent proteolysis in dystrophic myotubes.
AuthorsAlderton JM, Steinhardt RA
JournalJ Biol Chem
PubMed ID10734092
To estimate calpain proteolysis, we measured the hydrolysis rate of a fluorogenic calpain substrate in individual resting normal and dystrophic mdx mouse myotubes in culture. Hydrolysis rates were high during myoblast and myotube alignment and fusion. After alignment and fusion ceased, hydrolysis rates declined. For normal myotubes, hydrolysis remained low ... More
Visualization of the attachment organelle and cytadherence proteins of Mycoplasma pneumoniae by immunofluorescence microscopy.
AuthorsSeto S, Layh-Schmitt G, Kenri T, Miyata M
JournalJ Bacteriol
PubMed ID11160093
A method was developed for protein localization in Mycoplasma pneumoniae by immunofluorescence microscopy. The P1 adhesin protein was revealed to be located at least at one cell pole in all adhesive cells, as has been observed by immunoelectron microscopy. Cell images were classified according to P1 localization and assigned by ... More
Circuit-specific alterations in hippocampal synaptophysin immunoreactivity predict spatial learning impairment in aged rats.
AuthorsSmith TD, Adams MM, Gallagher M, Morrison JH, Rapp PR
JournalJ Neurosci
PubMed ID10964964
The present study examined the long-standing concept that changes in hippocampal circuitry contribute to age-related learning impairment. Individual differences in spatial learning were documented in young and aged Long-Evans rats by using a hippocampal-dependent version of the Morris water maze. Postmortem analysis used a confocal laser-scanning microscopy method to quantify ... More
Overexpression of aldehyde dehydrogenase-2 (ALDH2) transgene prevents acetaldehyde-induced cell injury in human umbilical vein endothelial cells: role of ERK and p38 mitogen-activated protein kinase.
Acetaldehyde, the major ethanol metabolite that is far more toxic and reactive than ethanol, has been postulated to be responsible for alcohol-induced tissue and cell injury. This study was to examine whether facilitated acetaldehyde metabolism affects acetaldehyde-induced oxidative stress and apoptosis. Transgene-encoding human aldehyde dehydrogenase-2 (ALDH2), which converts acetaldehyde into ... More