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Policosanol is a hypocholesterolemic derived from sugar cane and corn that downregulates blood cholesterol levels. It can further lower blood pressure and reduce liver inflammation. Policosanol can also affect vascular calcification, however, its molecular mechanisms are not well understood. This study investigated the effect of policosanol on vascular calcification and its molecular mechanism. Policosanol decreased the expression of inorganic phosphate (Pi)-induced osteogenic genes such as distal-less homeobox 5 (Dlx5) and runt-related transcription factor 2 (Runx2). In addition, following policosanol treatment, adenosine monophosphate-activated protein kinase (AMPK) phosphorylation increased in a time-dependent manner. The constitutively active form of AMPK (CA-AMPK) dramatically suppressed Pi-induced Dlx5 and Runx2 protein levels. Inactivation of AMPK using compound C (Com. C; AMPK inhibitor) recovered policosanol-suppressed Alizarin Red S staining levels. Insulin-induced genes (INSIGs) were induced by CA-AMPK, their overexpression suppressed Pi-induced Dlx5 and Runx2 expression. Taken together, the results demonstrate that policosanol inhibits Pi-induced vascular calcification by regulating AMPK-induced INSIG expression in vascular smooth muscle cells.

BACKGROUND A survival paradox of stage IIB/IIC and IIIA colon cancer has been consistently observed throughout revisions of the TNM system. This study aimed to understand this paradox with clinicopathological and molecular differences. METHODS Clinicopathological characteristics of patients with pathologically confirmed stage IIB/IIC or IIIA colon cancer were retrospectively reviewed from a database. Publicly available molecular data were retrieved, and intrinsic subtypes were identified and subjected to gene sets enrichment analysis (GSEA). RESULTS Among the 159 patients included in the clinicopathological analysis, those at stage IIB/IIC had worse 3-year disease-free and overall survival than those at stage IIIA (59.3% vs 91.7%, P

PURPOSE To compare the cerebral uptake and binding potential of [18 F]FCWAY and [18 F]Mefway in the rodent to assess their potential for imaging serotonin 1A (5-HT1A ) receptors. MATERIALS AND METHODS In vitro liver microsomal studies were performed to evaluate the degree of defluorination. Dynamic positron emission tomography (PET) studies were then conducted for 2 h with or without an anti-defluorination agent. The regions of interest were the hippocampus and frontal cortex (5-HT1A target regions) and the cerebellum (5-HT1A nontarget region). The in vivo kinetics of the radioligands were compared based on the brain uptake values and target-to-nontarget ratio. We also performed a comparison of binding potential (BPND ) as a steady-state binding parameter. Finally, binding affinities to 5-HT1A receptors were assessed in Chinese hamster ovary cells (CHO-K1) cells expressing human recombinant 5-HT1A receptors. RESULTS The radiochemical yield of [18 F]Mefway was slightly higher than that of [18 F]FCWAY (19 vs. 15%). With regard to metabolic stability against defluorination, both compounds exhibited similar stability in rat liver microsomes, but [18 F]Mefway displayed higher stability in the human microsome (defluorination ratio at 30 min: 32 vs. 29 in rat liver microsomes, 31 vs. 64 in human liver microsomes for [18 F]Mefway and [18 F]FCWAY, respectively). There were no significant differences in brain uptake, the target-to-nontarget ratios, and the BPND (at hippocampus, peak brain uptakes: 6.9 vs. 8.5, target-to-nontarget ratios: 6.9 vs. 8.5, BPND : 5.2 vs. 6.2 for [18 F]Mefway and [18 F]FCWAY). The binding affinity of [18 F]Mefway was considerably higher than that of [18 F]FCWAY (IC50 : 1.5 nM vs. 2.2 nM). CONCLUSION [18 F]Mefway exhibits favorable characteristics compared to [18 F]FCWAY in rodents, and may be a promising radioligand for use in human subjects. Synapse 68:595-603, 2014. © 2014 Wiley Periodicals, Inc.

Introduction: [18F]MeFWAY has been developed for imaging the serotonin 1A receptors in the brain. The purpose of this study were to verify the metabolic stability of [18F]MeFWAY, to measure the degree of defluorination of [18F]MeFWAY in vivo, to investigate methods of inhibition of defluorination of [18F]MeFWAY, and to assess the efficacy of [18F]MeFWAY in rat brains in vivo. Methods: MicroPET experiments in rats were conducted to confirm the distribution of radioactivity in the brain. Nondisplaceable binding potential (BPND) in the hippocampus and frontal cortex were also analyzed. Miconazole and fluconazole were tested for the ability to suppress defluorination of [18F]MeFWAY. We conducted a blockade and displacement experiment by treating with WAY-100635. Results: In vitro stability tests showed that MeFWAY was very stable in serum for 6 h, but PET revealed that authentic [18F]MeFWAY underwent significant defluorination in vivo. In vitro inhibition study against decreasing parent activity in liver microsomes, miconazole and fluconazole suppressed metabolic elimination of MeFWAY. However, in the PET study, fluconazole showed more potent inhibitory activity than miconazole. In the suppression of metabolizing enzymes using fluconazole, radioactivity in skull was dramatically decreased by 81% (compared with 69% with miconazole) and it was coupled with an increase in brain uptake. Moreover, BPND in hippocampus was 5.53 and 2.66 in frontal cortex. The blockade and displacement study showed the specificity of [18F]MeFWAY to 5-HT1A receptors. Conclusion: In the rat brain, [18F]MeFWAY microPET showed skull uptake due to defluorination in vivo. We can effectively overcome this drawback with fluconazole. Synapse, 2012. © 2012 Wiley Periodicals, Inc.

Purpose: Postinjection transmission positron emission tomography(PET) may be useful for shortening the total scan time. In this study, the effect of post-transmission scanning was assessed using PET on a phantom (NU4) and actual rat brain. Methods: Transmission was performed using57Co for 15 min. After a 15-min pre-transmission scan, emission PET was performed in list mode for 1 h, followed by an additional 15-min post-transmission scan. To compare the pre-transmission and post-transmission results, we measured nonuniformity, the recovery coefficient, and the spillover ratio (SOR) using NU4 and rat phantoms. The authors also assessed cerebral glucose metabolism using 18F-fluorodeoxyglucose (FDG) PET and the binding potential for 18F-fluorinated N-3-fluoropropyl-2-β-carboxymethoxy-3-β-(4-iodophenyl)nortropane (FP-CIT) in rat brain for differences between pre-transmission and post-transmission scanning. Results: Nonuniformity and the SORs for air and water were comparable on the pre-transmission and post-transmission scans. With FDG-PET, after attenuation and scatter corrections no differences were observed in the brain regions on the pre-transmission and post-transmission scans. With FP-CIT-PET, the binding potentials were also not significantly different. Conclusions: In the present study, we validated a post-transmission method for PET of the rat brain. Post-transmission PET was reliable, and the results were comparable to those of pre-transmission PET. Post-transmission PET eliminates the early tracer uptake time in the PETimaging, making it possible to determine uptake in the conscious subject, which may provide more realistic, “normal” metabolic measurements. Thus, post-transmission PET may be a useful option for increasing the number of subjects who can be evaluated.

Aim: To evaluate the efficacy and safety of radioimmunotherapy (RIT) with radioiodinated human/murine chimeric anti-CD20 monoclonal antibody rituximab (131I-rituximab) for treating Korean patients with relapsed or refractory B-cell non-Hodgkin's lymphomas (NHL). Methods: All patients received unlabeled rituximab 70 mg immediately prior to the administration of a therapeutic dose (median dose: 7.3 GBq) of 131I-rituximab. The tumor response was evaluated 1 month later by contrast enhanced 18F-fludeoxyglucose positron emission tomography-computed tomography. Results: Between May 2004 and October 2006, 24 patients received single treatment with 131I-rituximab. The overall response rate (ORR) was 29%; 46% (three complete responses, two partial responses (PR) for patients with low grade B-cell NHL (LGL) and 9% (one PR) for patients with diffuse large B-cell lymphoma (DLBCL). After a median follow-up of 55 months, the median progression-free survival (PFS) for all the patients was 2.2 months. The median overall survival (OS) was 11.3 months. There were statistically significant differences between the LGL and the DLBCL for the median PFS (4.5 months vs 1.3 months, respectively, P = 0.0007) and the median OS (30.3 months vs 6.5 months, respectively, P = 0.0295). Grades 3–4 thrombocytopenia and neutropenia occurred in 33% (8/24) and 21% (5/24) of the patients, respectively. Conclusion: RIT with 131I-rituximab seems to be effective and tolerable for patients with refractory LGL, although this treatment had modest activity in patients with refractory DLBCL. Further studies are warranted to determine the efficacy of 131I-rituximab for treating the patients with DLBCL.

123 I-FP-CIT and 18 F-FP-CIT are radiotracers which are widely used to diagnose Parkinson's disease (PD). However, to our knowledge, no studies to date have made head-to-head comparisons between 123 I-FP-CIT and 18 F-FP-CIT. Therefore, in this study, 123 I-FP-CIT SPECT/CT was compared with 18 F-FP-CIT PET/CT in the same cohort of subjects. Patients with PD and essential tremor (ET) underwent 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT. Visual and semiquantitative analyses were conducted. The specific binding ratio (SBR) and putamen to caudate ratio (PCR) were compared between subjects who underwent 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT. Visual analysis showed that the striatal uptake of both radiotracers was decreased in the PD group, whereas striatal uptake was intact in the ET group. The SBR between 123 I-FP-CIT SPECT/CT and 18 F-FP-CIT PET/CT showed a positive correlation (r = .78, p < .01). However, the mean SBRs on 18 F-FP-CIT PET/CT were higher than those on 123 I-FP-CIT SPECT/CT (2.19 ± .87 and 1.22 ± .49, respectively; p < .01). The PCRs in these two modalities were correlated with each other (r = .71, p < .01). The mean PCRs on 18 F-FP-CIT PET/CT were not significantly higher than those on 123 I-FP-CIT SPECT/CT (1.31 ± .19 and 0.98 ± .06, respectively; p = .06). These preliminary results indicate that the uptake of both 123 I-FP-CIT and 18 F-FP-CIT was decreased in the PD group when compared with the ET controls. Visual analyses using both methods did not affect the diagnostic accuracy in this study. However, semiquantitative analysis indicated a better contrast of 18 F-FP-CIT PET/CT relative to 123 I-FP-CIT SPECT/CT.

Objective Nicotinic acetylcholine receptors have close interactions with the dopaminergic system and play critical roles in cognitive function. The purpose of this study was to compare these receptors between living PD patients and healthy subjects. Methods Nicotinic acetylcholine receptors were imaged in 10 nondemented Parkinson's disease patients and 15 age-matched healthy subjects using a single-photon emission computed tomography ligand [123I]5-iodo-3-[2(S)-2-azetidinylmethoxy]pyridine. Using an arterial input function, we measured the total distribution volume (V; specific plus nondisplaceable), as well as the delivery (K1). Results Parkinson's disease showed a widespread significant decrease (approximately 10%) of V in both cortical and subcortical regions without a significant change in K1. Interpretation These results indicate the importance of extending the study to demented patients. Ann Neurol 2006;59:174–177

The clinical distinction between dopa-responsive dystonia (DRD) and juvenile Parkinson's disease JPD) can pose a diagnostic challenge. Both conditions are dopa responsive. However, long-term L-dopa benefit is very different between the two. The difference in the prognosis is due to presence or absence of nigral cell loss. In JPD, there is degenerative nigral cell loss, whereas there are enzymatic defects in dopamine synthesis without cell loss in DRD. Mutations have been found in the GTP cyclohydrolase I (GCH-I) and tyrosine hydroxylase genes in DRD. As the discovered mutations are multiple and more are expected to be found, it is difficult to confirm or exclude DRD by mutation studies. Measurement of cerebrospinal fluid (CSF) neopterin will detect DRD from mutations in the GCH-I gene but not from mutations in tyrosine hydroxylase. The dopamine transporter (DAT) is a protein in the dopaminergic nerve terminals. (1R)-2beta-Carbomethoxy-3beta-(4-[123I]iodophenyl)tropane ([123I]beta-CIT) is a ligand for the DAT, and it was shown to be a useful nuclear imaging marker for neurons that degenerate in Parkinson's disease (PD). As DRD was shown to have a normal DAT without nigral cell loss in a postmortem study, we predicted that the DAT measured in vivo by nuclear imaging will be normal in DRD and will differentiate DRD from JPD. Therefore, we performed [123I]beta-CIT single-photon emission computed tomography ([123I]beta-CIT SPECT) in clinically diagnosed DRD, PD, and JPD, and examined whether DAT imaging can differentiate DRD from PD and JPD. We then examined whether DAT imaging can provide a screening tool for molecular genetic studies, by studying mutations in the candidate gene GCH-I and measuring CSF neopterin. Five females (4 from two families, and 1 sporadic) were diagnosed as DRD based on early-onset foot dystonia and progressive parkinsonism beginning at ages 7 to 12. All patients were functioning normally on L-dopa 100 to 250 mg/day for up to 8 years. SPECT imaging was obtained after intravenous injection of [123I]beta-CIT; 15 healthy volunteers served as normal control, and 6 PD and 1 JPD as disease controls. [123I]beta-CIT striatal binding was normal in DRD, whereas it was markedly decreased in PD and JPD. Gene analysis showed a novel nonsense mutation in the GCH-I gene in one family. No mutation was found in the other family or in the sporadic case. CSF neopterin was markedly decreased in the 4 tested patients. [123I]beta-CIT SPECT is a sensitive method for probing the integrity of nigrostriatal dopaminergic nerve terminals. A normal striatal DAT in a parkinsonian patient is evidence for a nondegenerative cause of parkinsonism and differentiates DRD from JPD. Finding a new mutation in one family and failure to demonstrate mutations in the putative gene in other cases supports the usefulness of DAT imaging in diagnosing DRD.