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The nuclear pore complex forms a highly crowded selective barrier with intrinsically disordered regions at the nuclear membrane to coordinate nucleocytoplasmic molecular communications. Although oxidative stress is known to alter the barrier function, the molecular mechanism underlying this adaptive control of the nuclear pore complex remains unknown. Here we uncover a systematic control of the crowding barrier within the nuclear pore in response to various redox environments. Direct measurements of the crowding states using a crowding-sensitive FRET (Förster resonance energy transfer) probe reveal specific roles of the nuclear pore subunits that adjust the degree of crowding in response to different redox conditions, by adaptively forming or disrupting redox-sensitive disulfide bonds. Relationships between crowding control and the barrier function of the nuclear pore are investigated by single-molecular fluorescence measurements of nuclear transport. Based on these findings, we propose a proximal control model of molecular crowding in vivo that is dynamically regulated at the molecular level., 酸化ストレスが細胞の核膜機能を変える機構を解明 --環境に応じて分子の「混み具合」が変わる仕組み--. 京都大学プレスリリース. 2020-12-16.

Introduction [ 18 F]FEDAC ([ 18 F] 1 ) has potent binding affinity and selectivity for translocator protein (18kDa, TSPO), and has been used to noninvasively visualize neuroinflammation, lung inflammation, acute liver damage, nonalcoholic fatty liver disease, and liver fibrosis. We had previously synthesized [ 18 F] 1 in two steps: (i) preparation of [ 18 F]fluoroethyl bromide and (ii) coupling of [ 18 F]fluoroethyl bromide with the appropriate precursor ( 2 ) for labeling. In this study, to clinically utilize [ 18 F] 1 as a PET radiopharmaceutical and to transfer the production technique of [ 18 F] 1 to other PET centers, we simplified its preparation by using a direct, one-step, tosyloxy-for-fluorine substitution. We also performed an acute toxicity study as a major non-clinical safety test, and determined radiometabolites using human liver microsomes. Methods [ 18 F] 1 was prepared via direct 18 F-fluorination by heating the corresponding tosylated derivative ( 3 ) with [ 18 F]fluoride as its Kryptofix 222 complex in dimethyl sulfoxide at 110°C for 15min, following by HPLC purification. Non-clinical safety tests were performed for the extended single-dose toxicity study in rats, and for the in vitro metabolite analysis with human liver microsomal incubation. Results High quality batches of [ 18 F] 1 , compatible with clinical applications, were obtained. At the end of irradiation, the decay-corrected radiochemical yield of [ 18 F] 1 using 1 and 5mg of precursor based on [ 18 F]fluoride was 18.5±7.9% ( n =10) and 52.0±5.8% ( n =3), respectively. A single-dose of [ 18 F] 1 did not show toxicological effects for 14 days after the injection in male and female rats. In human liver microsomal incubations, [ 18 F] 1 was easily metabolized to [ 18 F]desbenzyl-FEDAC ([ 18 F] 10 ) by CYPs (4.2% of parent compound left 60min after incubation). Conclusion We successfully synthesized clinical grade batches of [ 18 F] 1 and verified the absence of innocuity of this radiotracer. [ 18 F] 1 will be used to first-in-human studies in our facility.

Relaxin-3 is a neuropeptide expressed in the brainstem, and predominantly localized in the gray matter of the midline dorsal pons termed the nucleus incertus. Relaxin-3-expressing neurons densely project axons rostrally to various forebrain regions including the septum, hippocampus, and lateral hypothalamus. Several relaxin-3 functions have been reported including food intake, stress responses, neuroendocrine function, emotion, and spatial memory. In addition, recently relaxin-3 and its receptor, RXFP3, were shown to regulate alcohol intake using an RXFP3 antagonist and RXFP3 gene knockout mice. In the present study, we investigated alcohol consumption in relaxin-3 knockout mice, and found that male but not female mice significantly drank more alcohol than wild-type mice in the two-bottle choice test. However, after chronic alcohol vapor exposure, wild-type and mutant mice did not show this difference in alcohol intake, although both genotypes exhibited increased alcohol consumption compared with non-alcohol-exposed control mice. There was no genotype difference in sucrose or quinine preference. These results suggest that the relaxin-3 neuronal system modestly affects alcohol preference and consumption.

Introduction [ 11 C]PBB3 is a clinically used positron emission tomography (PET) probe for in vivo imaging of tau pathology in the brain. Our previous study showed that [ 11 C]PBB3 was rapidly decomposed to a polar radiometabolite in the plasma of mice. For the pharmacokinetic evaluation of [ 11 C]PBB3 it is important to elucidate the characteristics of radiometabolites. In this study, we identified the chemical structure of a major radiometabolite of [ 11 C]PBB3 and proposed the metabolic pathway of [ 11 C]PBB3. Methods Carrier-added [ 11 C]PBB3 was injected into a mouse for in vivo metabolite analysis. The chemical structure of a major radiometabolite was identified using LC–MS. Mouse and human liver microsomes and liver S9 samples were incubated with [ 11 C]PBB3 in vitro. In silico prediction software was used to assist in the determination of the metabolite and metabolic pathway of [ 11 C]PBB3. Results In vivo analysis showed that the molecular weight of a major radiometabolite of [ 11 C]PBB3, which was called as [ 11 C]M2, was m/z 390 [M+H + ]. In vitro analysis assisted by in silico prediction showed that [ 11 C]M2, which was not generated by cytochrome P450 enzymes (CYPs), was generated by sulfated conjugation mediated by a sulfotransferase. Conclusion The major radiometabolite, [ 11 C]M2, was identified as a sulfated conjugate of [ 11 C]PBB3. [ 11 C]PBB3 was metabolized mainly by a sulfotransferase and subsidiarily by CYPs.

To fabricate a multilayer wiring using a low thermal expansion polyimide film, the adhesion of polyimide film on a thermally cured polyimide film must be secured. When the surface was plasma-treated by O2-CF4 = 1:1 gas, the adhesion was 30 times stronger (peel strength: at least 500 g/cm) than in the untreated case (peel strength: 15 g/cm). The film on the plasma-treated surface maintained strong adhesion for long periods of time in a high-temperature and high-humidity environment. The cause of improved adhesion was investigated by evaluating the plasma-treated polyimide surface by XPS and it was found that functional group, which seems to be COF, was formed.

We have previously reported marked enhancement of the cytocidal effect of bleomycin (BLM) on cancer cell suspensions in vitro by the combination with shock waves. In this study, we evaluated the synergistic effects on cancer cell proliferation and apoptosis in solid tumors. A spherical piezo-ceramic element was used as the shock wave source, with a pressure peak of 40 MPa. A human colon cancer cell line, SW480 was implanted onto the back of nude mice. Two thousand shock waves were administered to the tumor immediately following an intravenous injection of BLM at a dose of one-tenth of the LD(50). The tumor was extirpated at 3, 6, 12, 24, 72 h and 1 week following shock exposure. Cell proliferation and apoptosis were detected by Ki-67 using antibody MIB-1 and by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labeling (TUNEL) method. The lowest percentage (35.7%) of Ki-67-positive cells appeared 24 h following the treatment. The maximum apoptotic index was detected within 6 h following the treatment. Moreover, numerous large cells with enlarged nuclei were detected histologically. These results suggest that shock waves may enhance chemotherapeutic effects by increasing apoptosis and decreasing cell proliferation in the tumor tissue.

Qualitative and quantitative changes of lipid components during the growth stages were studied in E. floccosum. The acyl group components of total lipids of Trichophyton rubrum and Microsporum cookei were also examined. The lipids of E. floccosum amounted to approximately 4% of the dry cell weight. Neutral lipids mainly consisted of triglycerides and sterols, and major polar lipids were phosphatidylcholine, phosphatidylethanolamine, and an unknown lipid X. The fatty acids in tryglycerides and phospholipids were palmitic, palmitoleic, stearic, oleic, and linoleic acids. The unknown polar lipid X which appeared between phosphatidylethanolamine and cardiolipin on thin layer chromatography plates contained no phosphorus. There was no significant change in the fatty acid components of E. floccosum and T. rubrum during the cell growth, whereas profound changes occurred in M. cookei. The sterol components of E. floccosum showed striking changes depending on the growth stage.

Novel 26- and 28-membered macrocyclic tetraimine Schiff bases incorporating four thiophene units as ring constituents were synthesized by a nontemplate method starting from bis(5-formyl-2-thienyl)m...

An oxazole compound, tioxaprofen, exerted a strong anti-mycotic activity against Trichophyton mentagrophytes and T. rubrum, which were major dermatophytes from patients. It was found that tioxaprofen was a potent uncoupling agent of mitochondrial respiration.