Housekeeping while brain's storming Validation of normalizing factors for gene expression studies in a murine model of traumatic brain injury-2

Rmined at the indicated time point post-trauma. Each point corresponds to the measured level for one individual sample, normalized to the mean of all individual values at all times Horizontal bars represent the median of the measures for the group, vertical crosses represent the arithmetic mean. (C): control.<p><b>Copyright information:</b></p><p>Taken from "Housekeeping while brain's storming Validation of normalizing factors for gene expression studies in a murine model of traumatic brain injury"</p><p>http://www.biomedcentral.com/1471-2199/9/62</p><p>BMC Molecular Biology 2008;9():62-62.</p><p>Published online 8 Jul 2008</p><p>PMCID:PMC2500043.</p><p></p

In Vitro Targeting of Avidin-Expressing Glioma Cells with Biotinylated Persistent Luminescence Nanoparticles

Far red emitting persistent luminescence nanoparticles (PLNP) were synthesized and functionalized with biotin to study their targeting ability toward biotin-binding proteins. First, the interaction of biotin-decorated PLNP with streptavidin, immobilized on a plate, was shown to be highly dependent on the presence of a PEG spacer between the surface of the nanoparticles and the biotin ligand. Second, interaction between biotin-PEG-PLNP and free neutravidin in solution was confirmed by fluorescence microscopy. Finally, in vitro binding study on BT4C cells expressing lodavin fusion protein, bearing the extracellular avidin moiety, showed that such biotin-covered PLNP could successfully be targeted to malignant glioma cells through a specific biotin–avidin interaction. The influence of nanoparticle core diameter, incubation time, and PLNP concentration on the efficiency of targeting is discussed

Storage of Visible Light for Long-Lasting Phosphorescence in Chromium-Doped Zinc Gallate

ZnGa₂O₄:Cr³⁺ presents near-infrared long-lasting phosphorescence (LLP) suitable for in vivo bioimaging. It is a bright LLP material showing a main thermally stimulated luminescence (TSL) peak around 318 K. The TSL peak can be excited virtually by all visible wavelengths from 1.8 eV (680 nm) via d–d excitation of Cr³⁺ to above ZnGa₂O₄ band gap (4.5 eV–275 nm). The mechanism of LLP induced by visible light excitation is entirely localized around Cr_N2 ion that is a Cr³⁺ ion with an antisite defect as first cationic neighbor. The charging process involves trapping of an electron–hole pair at antisite defects of opposite charges, one of them being first cationic neighbor to Cr_N2. We propose that the driving force for charge separation in the excited states of chromium is the local electric field created by the neighboring pair of antisite defects. The cluster of defects formed by Cr_N2 ion and the complementary antisite defects is therefore able to store visible light. This unique property enables repeated excitation of LLP through living tissues in ZnGa₂O₄:Cr³⁺ biomarkers used for in vivo imaging. Upon excitation of ZnGa₂O₄:Cr³⁺ above 3.1 eV, LLP efficiency is amplified by band-assistance because of the position of Cr³⁺⁴T₁ (⁴F) state inside ZnGa₂O₄ conduction band. Additional TSL peaks emitted by all types of Cr³⁺ including defect-free Cr_R then appear at low temperature, showing that shallower trapping at defects located far away from Cr³⁺ occurs through band excitation

OS-Induced COX2 and VEGF Expression in RPE is CD36 Dependent

<div><p>(A–G) RT-PCR of cDNA from primary RPE cultures from Wistar rats and SHRs (A). Relative COX2 (B) and VEGF (G) mRNA expression (measured by real time RT-PCR. <i>n</i> = 6 wells per group; (B) *<i>p</i> = 0.0152 significant difference between control and CD36-deficient rats at 6 h; (G) *<i>p</i> = 0.0087 significant difference at 6 h) in RPE cells of Wistar (W) and SHR (S) rats exposed in culture to rod outer segments. COX2 (C and D) and VEGF (E and F) immunoreactivity (green) in 4-mo-old CD36^−/− (C and E) and CD36^+/+ (D and F) mice; tissues were counterstained with DAPI (nuclear stain).</p> <p>(H) Activation of CD36 with stimulating antibody evoked COX2 expression on RPE cell cultures from Wistar rats (W) and SHRs (measured by real time RT-PCR; <i>n</i> = 6 wells per group; *<i>p</i> = 0.0012 COX2 expression significantly different between control [Ctl] and antibody-treated [Ab] Wistar RPE culture).</p> <p>Photographs of immunohistochemical signal were taken with identical parameters in CD36^−/− and CD36^+/+ mice. Results are representative of at least three independent experiments. Ab, CD36 antibody FA6–152; CTL, control; RPE, retinal pigment epithelium. Scale bar: 50 μm</p></div

Choroidal Involution in COX2^−/− Mice

<div><p>(A and B) Micrographs of the retinal aspect of choriocapillaries in a frontal view of corrosion casts by scanning electron microscopy of 12-mo-old COX2^−/− (A) and COX2^+/+ (B) mice.</p> <p>(C–E) Quantification of the avascular area (<i>n</i> = 6 COX2^+/+ and <i>n</i> = 8 COX2^−/− eyes; *<i>p</i> = 0.007 COX2^−/− significantly different from COX2^+/+ at 12 mo) (C). Cross-sectional cuts of pericentral choroidal corrosion casts of COX2^−/− (D) and COX2^+/+ (E) mice.</p> <p>(F) Quantification of capillary thickness of 12-mo-old COX2^+/+ and COX2^−/− mice (<i>n</i> = 6 COX2^+/+ and <i>n</i> = 8 COX2^−/− eyes; *<i>p</i> = 0.0007).</p> <p>(G–I) Relative VEGF mRNA expression (by real time RT-PCR; <i>n</i> = 8 wells per group; *<i>p</i> = 0.0029 rod outer segments with DUP697 [R+D] significantly different from rod outer segments alone [R]) in primary RPE culture of Wistar rats (Ctl, white column), exposed to rod outer segments in absence (R, black column) or presence of the COX2 inhibitor DUP697 (10⁻⁶ M) (R+D, hatched column) (G). VEGF expression in 4-mo-old COX2^−/− (H) and COX2^+/+ (I) mice. Photomicrographs of immunohistochemical signal were taken with identical parameters.</p> <p>Results are representative of at least three independent experiments. m, months; RPE, retinal pigment epithelium. Scale bar: A, B, D, and E = 100 μm; H and I = 100 μm.</p></div

Retinal Degeneration in CD36-Deficient Animals

<div><p>(A) CD36 Western blot analysis of RPE/choroids complexes from Wistar rats (W) and SHRs S) (<i>n</i> = 4 eyes per group).</p> <p>(B and C) CD36 expression (green fluorescence) (B) and double-labeling with vascular marker BSA-1 (CD36 [green], BSA-1 [red], DAPI [blue]) (C) in CD36^+/+ mice (representative picture of three independent experiments).</p> <p>(D and E) Hemalun stained semi thin sections of 10-mo-old CD36-deficient SHRs (D) and control Wistar (W) rats (E).</p> <p>(F) Outer nuclear layer measurements of 10-mo-old Wistar rats (W; <i>n</i> = 6) SHRs (S; <i>n</i> = 8) (*<i>p</i> < 0.0001).</p> <p>(G and H) Hemalun-stained semi-thin sections (and periodic acid Schiff-stained paraffin sections [inset]) of 1-y-old CD36^−/− mice (G) and age-matched WT mice (H).</p> <p>(I) ONL thickness measurements in eyes of CD36^−/− (black bars; <i>n</i> = 10) and CD36^+/+ (white columns; <i>n</i> = 6) mice at different ages (*<i>p</i> = 0.0095 significant difference at 12 mo).</p> <p>(J–L) Transmission electron microscopy of the RPE and outer segments in SHRs (J), and CD36^−/− mice (K) and a CD36-expressing congener strain (CD36^+/+ mice) (L).</p> <p>Results are representative of at least three independent experiments. Scale bar: B, C, D, E, G, and H = 50 μm; J–L = 5μm.</p></div