82 research outputs found
Additional file 1 of Improved synthesis of 6-bromo-7-[11C]methylpurine for clinical use
Additional file 1. Table S1: Fraction of [11C]7m6BP determined by TLC; Figure S1: Schematic diagram of the automated system used for [11C]7m6BP synthesis; Figure S2: Typical image of a developed TLC plate spotted with a reaction mixture
Synthesis and Evaluation of Novel Radioligands for Positron Emission Tomography Imaging of the Orexin‑2 Receptor
Orexin receptors
(OXRs) in the brain have been implicated in diverse
physiological and neuropsychiatric conditions. Here we describe the
design, synthesis, and evaluation of OXR ligands related to (1<i>R,</i>2<i>S</i>)-2-(((2-methyl-4-methoxymethylpyrimidin-5-yl)Âoxy)Âmethyl)-<i>N</i>-(5-fluoropyridin-2-yl)-2-(3-fluorophenyl)Âcyclopropanecarboxamide
(<b>9a</b>) applicable to positron emission tomography (PET)
imaging. Structural features were incorporated to increase binding
affinity for OXRs, to enable carbon-11 radiolabeling, and to adjust
lipophilicity considered optimal for brain penetration and low nonspecific
binding. <b>9a</b> displayed nanomolar affinity for OXRs, and
autoradiography using rat brain sections showed that specific binding
of [<sup>11</sup>C]<b>9a</b> was distributed primarily to neocortical
layer VI and hypothalamus, consistent with reported localizations
of orexin-2 receptors (OX<sub>2</sub>Rs). In vivo PET study of [<sup>11</sup>C]<b>9a</b> demonstrated moderate uptake of radioactivity
into rat and monkey brains under deficiency or blockade of P-glycoprotein,
and distribution of PET signals in the brain was in agreement with
autoradiographic data. Our approach and findings have provided significant
information for development of OX<sub>2</sub>R PET tracers
Benzyl [<sup>11</sup>C]Hippurate as an Agent for Measuring the Activities of Organic Anion Transporter 3 in the Brain and Multidrug Resistance-Associated Protein 4 in the Heart of Mice
Multidrug resistance-associated protein
4 (MRP4) and organic anion
transporter 3 (OAT3) mediate the efflux of organic anions from the
brain and heart. In this study, we have developed a probe for estimating
the activity of these transporters in these tissues using positron
emission tomography. Several <sup>11</sup>C-labeled hippuric acid
ester derivatives were screened with the expectation that they would
be hydrolyzed in situ to form the corresponding <sup>11</sup>C-labeled
organic acids in target tissues. Among the compounds screened, benzyl
[<sup>11</sup>C]Âhippurate showed favorable hydrolysis rates and uptake
properties in the target tissues of mice. Subsequent evaluation using
transporter knockout mice revealed that radioactivity was retained
in the brain and heart of <i>Oat3</i><sup>–/–</sup> and <i>Mrp4</i><sup>–/–</sup> mice, respectively,
compared with that of control mice after the intravenous administration
of benzyl [<sup>11</sup>C]Âhippurate. Benzyl [<sup>11</sup>C]Âhippurate
could therefore be used as a probe for estimating the activities of
OAT3 and MRP4 in mouse brain and heart, respectively
<i>In vivo</i> biodistribution experiments in nude mice bearing MIA PaCa-2 and A4 xenografts of radiolabeled anti-CD147 antibody 059-053.
<p>Samples were collected and weighted, and radioactivity was measured at day 1 (white bars), 2 (dot bars), 4 (gray bars) and 6 (black bars) after intravenous injection of 37 kBq each of [<sup>89</sup>Zr]059-053 (A) and [<sup>125</sup>I]059-053 (B). Data are expressed as mean ± SD (n = 5). *<i>P</i><0.01 vs. [<sup>89</sup>Zr]059-053 tumor uptake at each time point analyzed by ANOVA with the Student–Newman–Keuls method multiple comparison test.</p
PET imaging with <sup>89</sup>Zr-lableled anti-CD147 antibody 059-053.
<p>(<b>A</b>) Serial PET images (maximum-intensity-projection) of a nude mouse bearing MIA PaCa-2 (yellow arrowhead) and A4 (white arrowhead) xenografted tumors at 30 min, and days 1, 2, 4, and 6 after intravenous injection of 3.7 MBq [<sup>89</sup>Zr]059-053. PET images of the same mouse are shown at different scale settings. (<b>B</b>) Coronal (upper) and transaxial (lower) images of PET/CT in the mouse orthotopic pancreatic cancer model (yellow arrowhead, MIA Paca-2) at day 6 after injection.</p
Additional file 6: of Uniform intratumoral distribution of radioactivity produced using two different radioagents, 64Cu-cyclam-RAFT-c(-RGDfK-)4 and 64Cu-ATSM, improves therapeutic efficacy in a small animal tumor model
(a) Tumor growth ratios of the same set of treated groups as described in Fig. 3. *, †, ‡P < 0.05 for combination, 64Cu-RaftRGD, and 64Cu-ATSM vs. vehicle control, respectively. Tumor growth ratios (b) and body weight changes (c) of U87MG tumor-bearing mice after co-administration of 64Cu-RaftRGD and 64Cu-ATSM at 111 MBq (55.5 MBq for each agent) and 148 MBq (74 MBq for each agent). Values are the means ± standard deviations (n = 4/group). *, **P < 0.05 and 0.01, respectively for 111 MBq-group vs. 148 MBq group, respectively. It should be noted that although vehicle controls (b, c) were not performed simultaneously along with the 111 MBq and 148 MBq groups, all the three independent experiments (#1 and #2 extracted from Additional file 4 and Additional file 6a, respectively) showed a reproducibly steady increase of the tumor volume in the vehicle-treated mice. (PDF 337 kb
CD147 protein expression analysis of pancreatic cancer cell lines (MIA Paca-2, PANC-1, BxPC-3, and AsPC-1) and A4 as a negative control.
<p>(A) Western blotting analysis of total cell lysate using anti-CD147 antibody (upper panel) and Coomassie Brilliant Blue staining of the same PVDF membrane as a loading control (lower panel). The ratio of band intensity is shown under the panels. (B) Subcellular localization of CD147 protein determined by immunofluorescence staining with anti-CD147 antibody (red) and DAPI nucleic acid staining (blue). The ratio of CD147 intensity is shown on the right of the panels. (C) CD147 expression in MIA Paca-2 (upper) and A4 (lower) xenografted tumors determined by immunohistochemical staining of frozen sections (10 µm thick).</p
Effect of CHX treatment on histopathological images of rat livers.
<p>Hematoxylin and eosin stained sections of (A) control, (B) CHX 2 h, (C) 4 h and (D) 6 h. (B) At 2 h after CHX treatment, arrows show apoptotic cells showing marked condensation of cytoplasm and nuclear pyknosis. (C, D) Arrow heads show spotty hepatocellular necroses with mild neutrophil infiltration. Abbreviation: portal triad (PT). Scale bar: 100 µm.</p
Effects of E2110 on micturition interval in 8-OH-DPAT-infused (A) and SCL (B) rats.
<p>Values are expressed as mean ± S.E.M. of eight rats in 8-OH-DPAT-infused and SCL models; * <i>P</i> < 0.05 versus vehicle (Dunnett’s multiple test).</p
Schematic illustration of a model for description of E2110 PK/PD.
<p>C<sub>p</sub>, E2110 concentration in the central compartment; C<sub>e</sub>, E2110 concentration in the effect compartment; k<sub>a</sub>, absorption rate constant; k<sub>e0</sub>, equilibrium rate constant; V<sub>1</sub>, central volume of distribution; V<sub>2</sub>, peripheral volume of distribution.</p
- …