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512 pixels. The wavelength of the
incident X-ray beam was 1.55 Å during the experiments and the beam size at
sample was 320
the area of which was divided into 512
×
m
2
. The sample to SAXS detector distance was 1314 mm.
The accessible
q
range was from 0.009 to 0.417 Å
− 1
. The X - ray fl ux (
×
7 0
μ
10
12
photons/s) was strong enough to allow direct sample exposures. During the
measurements, a metal attenuator was installed in order to prevent the liquid
crystalline nanoparticle samples from X-ray damages. The exposure time was
about 1 s. Silver behenate was used for the
q
- range calibration and glassy
carbon for the intensity normalization. After the data acquisition, the obtained
two-dimensional (2D) images were integrated into one-dimensional (1D) scat-
tering curves by means of the Fit2D software (www.esrf.eu/computing/
scientifi c/FIT2D/). The backgrounds coming from the glass capillary and the
solvent were measured and subtracted using conventional procedures.
∼
11.3.3
Cell Culture Assays
11.3.3.1 Treatment and Differentiation of Human Neuroblastoma
SH-SY5Y Cells
The neuroblastoma cell line SH-SY5Y was kindly provided
by Dr. Jean-Marc Muller of the Institute of Physiology and Cell Biology (CNRS
UMR 6187, Poitiers, France). The cells were grown in culture medium DMEM
(Dulbecco' s modifi ed Eagle's medium), provided by Lonza (Belgium), and
supplemented with 1% pyruvate, 1% streptomycin (PennStrep), and 10% fetal
calf serum, after decomplementation by heat (all percentages are expressed in
vol/vol). The cell cultures were maintained at 37°C in a saturated humid atmo-
sphere containing 95% air and 5% CO
2
. Cell divisions were made when the
cells arrived at confl uence, using trypsin for detachment. The doubling time of
the investigated neuroblastoma cells was variable (between 2 and 14 days), and
therefore the confl uence of the cells had to be regularly monitored.
For the differentiation of the neuroblastomas, the cells were seeded, at an
initial density of 10
4
cells/cm
2
, in coated sterile plates. When they were esti-
mated to reach 80% confl uence, retinoic acid was added to the culture medium,
at a concentration of 10
M, by dilution from a stock ethanol solution with
concentration of 10
− 3
M. After 5 days of incubation in the presence of retinoic
acid, the cells were washed three times with DMEM. Then, they were incu-
bated for 3 days, in the absence or presence of BDNF (2 ng/ml), with added
monoolein-based lipid NP systems (containing EPA or OA), which were
prediluted in DMEM at different lipid concentrations.
μ
11.3.3.2 Confocal Fluorescence Microscopy Imaging of TrkB Recep-
tor Expression in Differentiated Neuroblastoma SH-SY5Y Cells
The
cells were seeded on glass slides (0.17 mm thick and 12 mm in a diameter) in
24-well plates sterilized in autoclave. When the cells were estimated to be at
80% confl uence, a treatment with retinoic acid was effected for 5 days, and
then the cells were fi xed a few hours before the confocal microscopy imaging.
The fi xation was performed by removal of the medium, addition of 4% para-
formaldehyde for 10 min, followed by saturation of the latter with 50 mM
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