[18F]DAA1106: Automated radiosynthesis using spirocyclic iodonium ylide and preclinical evaluation for positron emission tomography imaging of translocator protein (18 kDa)

DAA1106 (N-(2,5-dimethoxybenzyl)-N-(5-fluoro-2-phenoxyphenyl)acetamide), is a potent and selective ligand for the translocator protein (18?kDa, TSPO) in brain mitochondrial fractions of rats and monkey (K_i?=?0.043 and 0.188?nM, respectively). In this study, to translate [¹⁸F]DAA1106 for clinical studies, we performed automated syntheses of [¹⁸F]DAA1106 using the spirocyclic iodonium ylide (1) as a radiolabelling precursor and conducted preclinical studies including positron emission tomography (PET) imaging of TSPO in ischemic rat brains. Radiofluorination of the ylide precursor 1 with [¹⁸F]F^?, followed by HPLC separation and formulation, produced the [¹⁸F]DAA1106 solution for injection in 6% average (n?=?10) radiochemical yield (based on [¹⁸F]F^?) with >98% radiochemical purity and molar activity of 60–100?GBq/μmol at the end of synthesis. The synthesis time was 87?min from the end of bombardment. The automated synthesis achieved [¹⁸F]DAA1106 with sufficient radioactivity available for preclinical and clinical use. Biodistribution study of [¹⁸F]DAA1106 showed a low uptake of radioactivity in the mouse bones. Metabolite analysis showed that >96% of total radioactivity in the mouse brain at 60?min after the radiotracer injection was unmetabolized [¹⁸F]DAA1106. PET study of ischemic rat brains visualized ischemic areas with a high uptake ratio (1.9?±?0.3) compared with the contralateral side. We have provided evidence that [¹⁸F]DAA1106 could be routinely produced for clinical studies.     

No evidence for linkage between the loci for coagulation factor XIII-A and HLA

Summary The linkage analysis between the locus for coagulation factor XIII-A (F13A) and HLA region genes (HLA-A,-C,-B) was performed. In males, the maximum of lod scores between F13A and HLA was 0.33 at =0.30, and in females lod scores were negative at all values of . The results provided no evidence for close linkage between F13A and HLA genes.     

Industrialization of a Noncooking System for Alcoholic Fermentation from Grains

Alcoholic fermentation from grains with a noncooking system was successfully carried out for the first time on an industrial scale. The results were compared with those with a conventional high-temperature cooking system and a low-temperature cooking one and it was found that:

(1) The fermentation efficiency is equal or superior to that of the high-temperature cooking system.

(2) Mashing at a concentration high enough to obtain an average 14.2% final alcohol concentration can be very easily done on an industrial scale.

(3) The need for heavy fuel oil for the mashing process is eliminated.

(4) The noncooking system allows much energy saving in industrial production of alcohol from starchy materials.     

Radiation increases the cellular uptake of exosomes through CD29/CD81 complex formation

Exosomes mediate intercellular communication, and mesenchymal stem cells (MSC) or their secreted exosomes affect a number of pathophysiologic states. Clinical applications of MSC and exosomes are increasingly anticipated. Radiation therapy is the main therapeutic tool for a number of various conditions. The cellular uptake mechanisms of exosomes and the effects of radiation on exosome–cell interactions are crucial, but they are not well understood. Here we examined the basic mechanisms and effects of radiation on exosome uptake processes in MSC. Radiation increased the cellular uptake of exosomes. Radiation markedly enhanced the initial cellular attachment to exosomes and induced the colocalization of integrin CD29 and tetraspanin CD81 on the cell surface without affecting their expression levels. Exosomes dominantly bound to the CD29/CD81 complex. Knockdown of CD29 completely inhibited the radiation-induced uptake, and additional or single knockdown of CD81 inhibited basal uptake as well as the increase in radiation-induced uptake. We also examined possible exosome uptake processes affected by radiation. Radiation-induced changes did not involve dynamin2, reactive oxygen species, or their evoked p38 mitogen-activated protein kinase-dependent endocytic or pinocytic pathways. Radiation increased the cellular uptake of exosomes through CD29/CD81 complex formation. These findings provide essential basic insights for potential therapeutic applications of exosomes or MSC in combination with radiation.     

Characterization of a novel acetamidobenzoxazolone‐based PET ligand for translocator protein (18 kDa) imaging of neuroinflammation in the brain

We developed the novel positron emission tomography (PET) ligand 2‐[5‐(4‐[¹¹C]methoxyphenyl)‐2‐oxo‐1,3‐benzoxazol‐3(2H)‐yl]‐N‐methyl‐N‐phenylacetamide ([¹¹C]MBMP) for translocator protein (18 kDa, TSPO) imaging and evaluated its efficacy in ischemic rat brains. [¹¹C]MBMP was synthesized by reacting desmethyl precursor ( 1 ) with [¹¹C]CH₃I in radiochemical purity of ≥ 98% and specific activity of 85 ± 30 GBq/μmol (n = 18) at the end of synthesis. Biodistribution study on mice showed high accumulation of radioactivity in the TSPO‐rich organs, e.g., the lungs, heart, kidneys, and adrenal glands. The metabolite analysis in mice brain homogenate showed 80.1 ± 2.7% intact [¹¹C]MBMP at 60 min after injection. To determine the specific binding of [¹¹C]MBMP with TSPO in the brain, in vitro autoradiography and PET studies were performed in an ischemic rat model. In vitro autoradiography indicated significantly increased binding on the ipsilateral side compared with that on the contralateral side of ischemic rat brains. This result was supported firmly by the contrast of radioactivity between the ipsilateral and contralateral sides in PET images. Displacement experiments with unlabelled MBMP or PK11195 minimized the difference in uptake between the two sides. In summary, [¹¹C]MBMP is a potential PET imaging agent for TSPO and, consequently, for the up‐regulation of microglia during neuroinflammation.

     

Effects of atorvastatin and aspirin combined therapy on inflammatory responses in patients undergoing coronary artery bypass grafting

This study was conducted to compare the effects of atorvastatin plus aspirin combined therapy on inflammatory responses, endothelial cell function, and blood coagulation system in patients undergoing coronary artery bypass grafting (CABG) to aspirin monotherapy. The patients were randomized into atorvastatin plus aspirin combined therapy group and aspirin monotherapy group. Reduced total cholesterol in the combined therapy group was found in a short term of medication for 14 days. On postoperative day (POD)-14, inhibitory effects of the combined therapy on whole blood aggregation as well as platelet activation assessed by flow cytometry were stronger than those of the monotherapy. Furthermore, cytokine, cytokine receptors, c-reactive protein and alpha1-acid glycoprotein in the combined therapy group were down-regulated on POD-14. At the same time, circulating levels of thromboxane A(2), vascular endothelial growth factor and thrombin-antithrombin III complex as well as P-selectin, L-selectin and intercellular adhesion molecule-1 were down-regulated, while E-selectin and transforming growth factor-beta1 was up-regulated. Atorvastatin plus aspirin combined therapy may improve inflammatory responses, accelerated platelet function, vascular endothelial cell function, blood coagulation system at the early stage such as 14th day after CABG. In conclusion, atorvastatin and aspirin combined therapy may bring beneficial effects to the patient after CABG.     

Genomewide association analysis of human narcolepsy and a new resistance gene

Human narcolepsy is a hypersomnia that is affected by multiple genetic and environmental factors. One genetic factor strongly associated with narcolepsy is the HLA-DRB1*1501-DQB1*0602 haplotype in the human leukocyte antigen region on chromosome 6, whereas the other genetic factors are not clear. To discover additional candidate regions for susceptibility or resistance to human narcolepsy, we performed a genomewide association study, using 23,244 microsatellite markers. Two rounds of screening with the use of pooled DNAs yielded 96 microsatellite markers (including 16 markers on chromosome 6) with significantly different estimated frequencies in case and control pools. Markers not located on chromosome 6 were evaluated by the individual typing of 95 cases and 95 controls; 30 markers still showed significant associations. A strong association was displayed by a marker on chromosome 21 (21q22.3). The surrounding region was subjected to high-density association mapping with 14 additional microsatellite markers and 74 SNPs. One microsatellite marker (D21S0012m) and two SNPs (rs13048981 and rs13046884) showed strong associations (P < .0005; odds ratios 0.19-0.33). These polymorphisms were in a strong linkage disequilibrium, and no other polymorphism in the region showed a stronger association with narcolepsy. The region contains three predicted genes--NLC1-A, NLC1-B, and NLC1-C--tentatively named "narcolepsy candidate-region 1 genes," and NLC1-A and NLC1-C were expressed in human hypothalamus. Reporter-gene assays showed that the marker D21S0012m in the promoter region and the SNP rs13046884 in the intron of NLC1-A significantly affected expression levels. Therefore, NLC1-A is considered to be a new resistance gene for human narcolepsy.     

The R2TP complex: discovery and functions

The two closely related AAA+family ATPases Rvb1 and Rvb2 are part of several critical multiprotein complexes, and, thus, are involved in a wide range of cellular processes including chromatin remodelling, telomerase assembly, and snoRNP biogenesis. It was found that Rvb1 and Rvb2 form a tight functional complex with Pih1 (Protein interacting with Hsp90) and Tah1 (TPR-containing protein associated with Hsp90), which are two Hsp90 interactors. We named the complex R2TP. The complex was originally isolated from Saccharomyces cerevisiae and was, subsequently, identified in mammalian cells. R2TP was found to be required for box C/D snoRNP biogenesis in yeast and mammalian cells. More recently, several studies revealed that the complex is also involved in multiple biological processes including apoptosis, phosphatidylinositol-3 kinase-related protein kinase (PIKK) signalling, and RNA polymerase II assembly. In this review, we describe the discovery of the complex and discuss the emerging critical roles that R2TP plays in distinct cellular processes.