Maintenance of ZPA signaling in cultured mouse limb bud cells

Development ◽  
1993 ◽  
Vol 117 (4) ◽  
pp. 1421-1433 ◽  
Author(s):  
R. Anderson ◽  
M. Landry ◽  
K. Muneoka
Keyword(s):  
Culture Technique ◽  
Limb Bud ◽  
In Vivo Studies ◽  
Maintenance Activity ◽  
Vertebrate Limb ◽  
Mouse Limb ◽  
Zone Of Polarizing Activity

The positional signal localized to the posterior (zone of polarizing activity or ZPA) region of the vertebrate limb is transiently expressed during development and a decline in ZPA signaling is accelerated when posterior cells are dissociated and cultured in vitro. The evidence that cultured posterior cells display a precocious decline in ZPA signaling when compared to in vivo studies suggests that a factor present in the limb bud maintains or stabilizes ZPA signaling during limb outgrowth and that this maintenance factor is lost and/or exhausted in in vitro studies. We have developed a new culture technique, ‘microdissociation’, which preserves extracellular components that we have found to be necessary for ZPA signal maintenance. Our data suggest that the limb bud ectoderm produces a maintenance activity that becomes stored in the extracellular matrix where it acts on limb bud cells to stabilize the activity of the ZPA signal. Using our initial characterization of this maintenance activity, we have identified a growth factor, FGF-2 (bFGF), that can replace all of the ZPA signaling maintenance activity observed in microdissociate cultures. The existence of various members of the FGF family in the developing limb strongly argues a role for FGF in stabilizing ZPA signaling in vivo.

FGF-4 maintains polarizing activity of posterior limb bud cells in vivo and in vitro

Development ◽  
1993 ◽  
Vol 119 (1) ◽  
pp. 199-206 ◽  
Author(s):  
A. Vogel ◽  
C. Tickle
Keyword(s):  
Posterior Margin ◽  
Anterior Margin ◽  
Marked Decrease ◽  
Mesenchymal Cells ◽  
Apical Ectodermal Ridge ◽  
Limb Bud ◽  
Posterior Limb ◽  
Vertebrate Limb

The polarizing region is a major signalling tissue involved in patterning the tissues of the vertebrate limb. The polarizing region is located at the posterior margin of the limb bud and can be recognized by its ability to induce additional digits when grafted to the anterior margin of a chick limb bud. The signal from the polarizing region operates at the tip of the bud in the progress zone, a zone of undifferentiated mesenchymal cells, maintained by interactions with the apical ectodermal ridge. A number of observations have pointed to a link between the apical ectodermal ridge and signalling by the polarizing region. To test this possibility, we removed the posterior apical ectodermal ridge of chick wing buds and assayed posterior mesenchyme for polarizing activity. When the apical ectodermal ridge is removed, there is a marked decrease in polarizing activity of posterior cells. The posterior apical ectodermal ridge is known to express FGF-4 and we show that the decrease in polarizing activity of posterior cells of wing buds that normally follows ridge removal can be prevented by implanting a FGF-4-soaked bead. Furthermore, we show that both ectoderm and FGF-4 maintain polarizing activity of limb bud cells in culture.

Vitamin A alters the internal viscosity of fragments of limb-bud mesenchyme

Development ◽  
1980 ◽  
Vol 59 (1) ◽  
pp. 325-339
Author(s):  
T. E. Kwasigroch ◽  
D. M. Kochhar
Keyword(s):  
Retinoic Acid ◽  
Vitamin A ◽  
Mesenchymal Cells ◽  
Limb Bud ◽  
Mouse Limb ◽  
Vitamin A Acid ◽  
Internal Viscosity ◽  
Fusion Experiments

Two techniques were used to examine the effect of vitamin A compounds (vitamin A acid = retinoic acid and vitamin A acetate) upon the relative strengths of adhesion among mouse limb-bud mesenchymal cells. Treatment with retinoic acid in vivo and with vitamin A acetate in vitro reduced the rate at which the fragments of mesenchyme rounded-up when cultured on a non-adhesive substratum, but these compounds did not alter the behavior of tissues tested in fragment-fusion experiments. These conflicting results indicate that the two tests measure different activities of cells and suggest that treatment with vitamin A alters the property(ies) of cells which regulate the internal viscosity of tissues.

Development and characterization of highly selective target-sensitive liposomes for the delivery of streptokinase: in vitro/in vivo studies

Drug Delivery ◽  
2014 ◽  
Vol 23 (3) ◽  
pp. 791-797 ◽  
Author(s):  
Bhuvaneshwar Vaidya ◽  
Manasa K. Nayak ◽  
Debabrata Dash ◽  
Govind P. Agrawal ◽  
Suresh P. Vyas
Keyword(s):  
In Vivo Studies ◽  
Selective Target

Characterization of nociceptin receptors in the periphery: in vitro and in vivo studies

1999 ◽  
Vol 359 (3) ◽  
pp. 160-167 ◽  
Author(s):  
Raffaella Bigoni ◽  
Sandro Giuliani ◽  
G. Calo’ ◽  
Anna Rizzi ◽  
Remo Guerrini ◽  
...  
Keyword(s):  
In Vivo Studies

scholarly journals ENHANCED FLUORESCENCE IMAGING WITH DMSO-MEDIATED OPTICAL CLEARING

2010 ◽  
Vol 03 (03) ◽  
pp. 153-158 ◽  
Author(s):  
SANJEEV KARMA ◽  
JAMES HOMAN ◽  
CHARLES STOIANOVICI ◽  
BERNARD CHOI
Keyword(s):  
Fluorescence Emission ◽  
Model Systems ◽  
In Vivo Studies ◽  
In Vivo Model ◽  
Fluorescence Signal ◽  
Optical Clearing ◽  
Treated Site

Recent studies have demonstrated that topical application of glycerol on intact skin does not affect its optical scattering properties. Investigators from our research group recently revisited the use of dimethyl sulfoxide (DMSO) as an agent with optical clearing potential. We address the use of optical clearing to enhance quantitation of subsurface fluorescence emission. We employed both in vitro and in vivo model systems to study the effect of topical DMSO application on fluorescence emission. Our in vitro experiments performed on a tissue-simulating phantom suggest that DMSO-mediated optical clearing enables enhanced characterization of subsurface fluorophores. With topical DMSO application, a marked increase in fluorescence emission was observed. After 30 min, the fluorescence signal at the DMSO-treated site was 9× greater than the contralateral saline-treated site. This ratio increased to 13× at 105 min after agent application. In summary, DMSO is an effective optical clearing agent for improved fluorescence emission quantitation and warrants further study in preclinical in vivo studies. Based on outcomes from previous clinical studies on the toxicity profile of DMSO, we postulate that clinical application of DMSO as an optical clearing agent, can be performed safely, although further study is warranted.

Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE): Biochemical Features and Therapeutic Approaches

2007 ◽  
Vol 27 (1-3) ◽  
pp. 151-163 ◽  
Author(s):  
M. C. Lara ◽  
M. L. Valentino ◽  
J. Torres-Torronteras ◽  
M. Hirano ◽  
R. Martí
Keyword(s):  
Molecular Genetic ◽  
In Vivo Studies ◽  
Gene Encoding ◽  
Mitochondrial Neurogastrointestinal Encephalomyopathy ◽  
Mtdna Replication ◽  
Biochemical Features

Over the last 15 years, important research has expanded our knowledge of the clinical, molecular genetic, and biochemical features of mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). The characterization of mitochondrial involvement in this disorder and the seminal determination of its genetic cause, have opened new possibilities for more detailed and deeper studies on the pathomechanisms in this progressive and fatal disease. It has been established that MNGIE is caused by mutations in the gene encoding thymidine phosphorylase (TP), which lead to absolute or nearly complete loss of its catalytic activity, producing systemic accumulations of its substrates, thymidine (dThd) and deoxyuridine (dUrd). Findings obtained from in vitro and in vivo studies indicate that the biochemical imbalances specifically impair mitochondrial DNA (mtDNA) replication, repair, or both leading to mitochondrial dysfunction. We have proposed that therapy for MNGIE should be aimed at reducing the concentrations of these toxic nucleosides to normal or nearly normal levels. The first treatment, allogeneic stem-cell transplantation (alloSCT) reported in 2006, produced a nearly full biochemical correction of the dThd and dUrd imbalances in blood. Clinical follow-up of this and other patients receiving alloSCT is necessary to determine whether this and other therapies based on a permanent restoration of TP will be effective treatment for MNGIE.

scholarly journals 432. Characterization of a Novel Oncolytic Measles Virus Retargeted Against the Urokinase Receptor: In Vitro and In Vivo Studies

2006 ◽  
Vol 13 ◽  
pp. S166-S167
Author(s):  
Jaime R. Merchan ◽  
Caili Tong ◽  
Takafumi Nakamura ◽  
Ianko Iankov ◽  
Stephen J. Russell
Keyword(s):  
Measles Virus ◽  
Urokinase Receptor ◽  
In Vivo Studies

Preparation and characterization of technetium and rhenium tricarbonyl complexes bearing the 4-nitrobenzyl moiety as potential bioreductive diagnostic radiopharmaceuticals. In vitro and in vivo studies

2008 ◽  
Vol 43 (4) ◽  
pp. 741-748 ◽  
Author(s):  
Javier Giglio ◽  
Georgios Patsis ◽  
Ioannis Pirmettis ◽  
Minas Papadopoulos ◽  
Catherine Raptopoulou ◽  
...  
Keyword(s):  
In Vivo Studies ◽  
Rhenium Tricarbonyl
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