Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The improvement of commonly used Gd3+ -based MRI agents requires the design of new systems with optimized in vivo efficacy, pharmacokinetic properties, and specificity. To design these contrast agents, two parameters are usually considered: increasing the number of coordinated water molecules or increasing the rotational correlation time by increasing molecular weight and size. This has been achieved by noncovalent or covalent binding of low-molecular weight Gd3+ chelates to macromolecules or polymers. The grafting of these high-spin paramagnetic gadolinium chelates on metal oxide nanoparticles (SiO2, Al2O3) is proposed. This new synthetic strategy presents at least two main advantages: (1) a high T1-relaxivity for MRI with a 275% increase of the MRI signal and (2) the ability of nanoparticles to be internalized in cells. Results indicate that these new contrast agents lead to a huge reconcentration of Gd3+ paramagnetic species inside microglial cells. This reconcentration phenomenon gives rise to high signal-to-noise ratios on MR images of cells after particle internalization, from 1.4 to 3.75, using Al2O3 or SiO2 particles, respectively. The properties of these new particles will be further used to get new insight into gene therapy against glioma, using microglial cells as vehicles to simultaneously transport a suicide gene and contrast agents. Since microglia are chemoattracted to brain tumors, the presence of these new contrast agents inside the cells will lead to a better MRI determination of the in vivo location, shape, and borders of the tumors. These Gd3+-loaded microglia can therefore provide effective localization of tumors by MRI before applying any therapeutic treatment. The rate of carcinoma remission following a suicide gene strategy is also possible.
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PMID:Use of lanthanide-grafted inorganic nanoparticles as effective contrast agents for cellular uptake imaging. 1751 91

Cell patterning platforms support broad research goals, such as construction of predefined in vitro neuronal networks and the exploration of certain central aspects of cellular physiology. To easily combine cell patterning with Multi-Electrode Arrays (MEAs) and silicon-based 'lab on a chip' technologies, a microfabrication-compatible protocol is required. We describe a method that utilizes deposition of the polymer parylene-C on SiO2 wafers. Photolithography enables accurate and reliable patterning of parylene-C at micron-level resolution. Subsequent activation by immersion in fetal bovine serum (or another specific activation solution) results in a substrate in which cultured cells adhere to, or are repulsed by, parylene or SiO2 regions respectively. This technique has allowed patterning of a broad range of cell types (including primary murine hippocampal cells, HEK 293 cell line, human neuron-like teratocarcinoma cell line, primary murine cerebellar granule cells, and primary human glioma-derived stem-like cells). Interestingly, however, the platform is not universal; reflecting the importance of cell-specific adhesion molecules. This cell patterning process is cost effective, reliable, and importantly can be incorporated into standard microfabrication (chip manufacturing) protocols, paving the way for integration of microelectronic technology.
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PMID:Cell patterning on photolithographically defined parylene-C: SiO2 substrates. 2463 80