Linked Life Data

18330933

Source:http://linkedlifedata.com/resource/pubmed/id/18330933

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2008-3-17
pubmed:abstractText
Thermosensitive liposomes (TSL) with encapsulated proton (1H) magnetic resonance (MR) contrast agents have been proposed for noninvasive online temperature monitoring during tumor treatment using chemotherapy combined with hyperthermia (HT). The technique exploits the fact that water exchange between the TSL interior and exterior is increased and/or the encapsulated 1H MR contrast agent is released near the gel-to-liquid crystalline phase transition temperature (Tm) of TSL and thus shortens the 1H MR relaxation time of tissue. In this work, newly developed, phosphatidylglyceroglycerol (DPPGOG)-based TSL with encapsulated 1H MR longitudinal relaxation time (T1)-shortening gadodiamide (Gd-DTPA-BMA) were characterized in vitro by measuring the temperature dependence of the T1 of these gadodiamide-containing DPPGOG-TSL samples between 30 and 50 degrees C. The measurements revealed that the T1 nonlinearly slightly decreased with increasing temperature from 30 to 37 degrees C, mainly due to increased water exchange between the gadodiamide-containing DPPGOG-TSL interior and exterior with the exception of negligible gadodiamide release. This implies that gadodiamide-containing DPPGOG-TSL were stable at temperatures < or =37 degrees C, which was also confirmed by an independent stability study. From 37 to 44 degrees C, the T1 nonlinearly markedly decreased with increasing temperature since encapsulated gadodiamide was rapidly released. Above 44 degrees C, gadodiamide was completely released and the T1 was directly proportional to temperature while heated from 44 to 50 degrees C and cooled from 50 to 30 degrees C, respectively. Additionally, gadodiamide release was theoretically quantified and this calculated concentration was consistent with the actually released amount directly obtained from the cooling course of empty DPPGOG-TSL with completely released gadodiamide.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1555-4317
pubmed:author
pubmed:copyrightInfo
(c) 2008 John Wiley & Sons, Ltd.
pubmed:issnType
Electronic
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
19-26
pubmed:dateRevised
2010-10-29
pubmed:meshHeading
pubmed:articleTitle
In vitro characterization of phosphatidylglyceroglycerol-based thermosensitive liposomes with encapsulated 1H MR T1-shortening gadodiamide.
pubmed:affiliation
Department of Internal Medicine III, University Hospital Grosshadern, University of Munich, Munich, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't