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Substituted alkylammonium ions (protonated hydroxy amine and diamine) were intercalated into layered niobate K4Nb6O17 in order to introduce functional substituents into the interlayer spaces of the niobate. In the case of reaction with 3-hydroxypropylammonium ion, the intercalation compound incorporated the ammonium ions in a bilayer arrangement, by which the hydroxyl substituents were located in the middle of the interlayer spaces to form intermolecular hydrogen bonding. For the intercalation compounds with alkyldiammonium ions, the intercalated alkyldiammonium ions were present in monolayer and oriented transversally with respect to the niobate layers. [ABSTRACT FROM AUTHOR]

Substituted alkylammonium ions (protonated hydroxy amine and diamine) were intercalated into layered niobate K4Nb6O17 in order to introduce functional substituents into the interlayer spaces of the niobate. In the case of reaction with 3-hydroxypropylammonium ion, the intercalation compound incorporated the ammonium ions in a bilayer arrangement, by which the hydroxyl substituents were located in the middle of the interlayer spaces to form intermolecular hydrogen bonding. For the intercalation compounds with alkyldiammonium ions, the intercalated alkyldiammonium ions were present in monolayer and oriented transversally with respect to the niobate layers. [ABSTRACT FROM AUTHOR]

Introduction: ACE cleaves angiotensin I (Ang I) to angiotensin II (Ang II) inducing vasoconstriction via Ang II type 1 (AT1) receptor, while ACE2 cleaves Ang II to Ang (1-7) causing vasodilatation by acting on the Mas receptor. In diabetic kidney disease (DKD), it is still unclear whether plasma or urine ACE2 levels predict renal outcomes or not., Research Design and Methods: Among 777 participants with diabetes enrolled in the Urinary biomarker for Continuous And Rapid progression of diabetic nEphropathy study, the 296 patients followed up for 9 years were investigated. Plasma and urinary ACE2 levels were measured by the ELISA. The primary end point was a composite of a decrease of estimated glomerular filtration rate (eGFR) by at least 30% from baseline or initiation of hemodialysis or peritoneal dialysis. The secondary end points were a 30% increase or a 30% decrease in albumin-to-creatinine ratio from baseline to 1 year., Results: The cumulative incidence of the renal composite outcome was significantly higher in group 1 with lowest tertile of plasma ACE2 (p=0.040). Group 2 with middle and highest tertile was associated with better renal outcomes in the crude Cox regression model adjusted by age and sex (HR 0.56, 95% CI 0.31 to 0.99, p=0.047). Plasma ACE2 levels demonstrated a significant association with 30% decrease in ACR (OR 1.46, 95% CI 1.044 to 2.035, p=0.027) after adjusting for age, sex, systolic blood pressure, hemoglobin A1c, and eGFR., Conclusions: Higher baseline plasma ACE2 levels in DKD were protective for development and progression of albuminuria and associated with fewer renal end points, suggesting plasma ACE2 may be used as a prognosis marker of DKD., Trial Registration Number: UMIN000011525., Competing Interests: Competing interests: JW receives speaker honoraria from AstraZeneca, Bayer, Boehringer Ingelheim, Daiichi Sankyo, Kyowa Kirin, Novo Nordisk, and Mitsubishi Tanabe, and receives grant support from Bayer, Chugai, Kyowa Kirin, Otsuka, Shionogi, Sumitomo, and Mitsubishi Tanabe., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Although smectite-type clays are used as heterogeneous media for photofunctional guest molecules, the guest species are limited to cationic or polar molecules because of the intrinsic negative electric charges of clay particles. Nevertheless, in this study, aqueous clay colloids are reported to affect the photoisomerization kinetics of anionic and cationic azobenzene molecules dissolved in the colloids. Under UV-light irradiation, the clay colloids decelerate trans -to- cis isomerization, while under visible-light irradiation, the clay colloids accelerate cis -to- trans isomerization. In addition, the sol-gel transition of clay colloids affects the kinetics. The results considerably expand the applicability of clay colloids as matrixes for functional organic species., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background: Although various biomarkers predict cardiovascular event (CVE) in patients with diabetes, the relationship of urinary glycan profile with CVE in patients with diabetes remains unclear. Methods: Among 680 patients with type 2 diabetes, we examined the baseline urinary glycan signals binding to 45 lectins with different specificities. Primary outcome was defined as CVE including cardiovascular disease, stroke, and peripheral arterial disease. Results: During approximately a 5-year follow-up period, 62 patients reached the endpoint. Cox proportional hazards analysis revealed that urinary glycan signals binding to two lectins were significantly associated with the outcome after adjustment for known indicators of CVE and for false discovery rate, as well as increased model fitness. Hazard ratios for these lectins (+1 SD for the glycan index) were UDA (recognizing glycan: mixture of Man5 to Man9): 1.78 (95% CI: 1.24-2.55, P = 0.002) and Calsepa [High-Man (Man2-6)]: 1.56 (1.19-2.04, P = 0.001). Common glycan binding to these lectins was high-mannose type of N -glycans. Moreover, adding glycan index for UDA to a model including known confounders improved the outcome prediction [Difference of Harrel's C-index: 0.028 (95% CI: 0.001-0.055, P = 0.044), net reclassification improvement at 5-year risk increased by 0.368 (0.045-0.692, P = 0.026), and the Akaike information criterion and Bayesian information criterion decreased from 725.7 to 716.5, and 761.8 to 757.2, respectively]. Conclusion: The urinary excretion of high-mannose glycan may be a valuable biomarker for improving prediction of CVE in patients with type 2 diabetes, and provides the rationale to explore the mechanism underlying abnormal N -glycosylation occurring in patients with diabetes at higher risk of CVE. Trial Registration: This study was registered with the University Hospital Medical Information Network on June 26, 2012 (Clinical trial number: UMIN000011525, URL: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000013482)., Competing Interests: MYa was a former employee of GP BioSciences Co., Ltd., and is currently an employee of GlycoTechnica Co., Ltd. JW received speaker honoraria from Astra Zeneca, Daiichi Sankyo, MSD, Novartis, Tanabe Mitsubishi, Taisho Toyama and received grant support from Baxter, Chugai, Dainippon Sumitomo, Ono, and Teijin. There are no other relevant declarations relating to employment, consultancy, patents, products in development, or marketed products. This does not alter the authors' adherence to all Frontiers in Cardiovascular Medicine policies on sharing data and materials. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Mise, Imamura, Yamaguchi, Watanabe, Higuchi, Katayama, Miyamoto, Uchida, Nakatsuka, Eguchi, Hida, Nakato, Tone, Teshigawara, Matsuoka, Kamei, Murakami, Shimizu, Miyashita, Ando, Nunoue, Yoshida, Yamada, Shikata and Wada.)

We investigated photoinduced electron accumulation in a colloidal system of layered hexaniobate that is known as a photocatalytically active wide band-gap semiconductor, and attempted to control the photoresponse by introducing additives into the colloid. The inorganic nanosheets were obtained by exfoliation of the layered oxide. UV-irradiation of the colloids led to electron accumulation in the nanosheets to generate reduced niobate species. Propylammonium ions introduced as the exfoliating reagent and present as the counter ions of niobate nanosheets were indicated as the electron donor that stabilized the electron-accumulating state. Yield and half-life of the reduced niobate species greatly increased by adding an appropriate amount of photochemically inert clay nanosheets, while they increased only a little by the addition of molecular electron donors such as EDTA and triethanolamine. Moreover, the molecular species diminished the enhancement effect of the clay nanosheets. The results suggested that the photochemical event was not explained by direct interactions between the semiconductor nanosheets and the additives at molecular level but governed by indirect interactions between the colloid components regulated by the colloid structure., (Copyright © 2010 Elsevier Inc. All rights reserved.)

The syntheses of all stereoisomers of tetrasubstituted tetrahydrofuran lignan were accomplished, and the antimicrobial activity was examined. The 9,9'-diol compound bearing (7R,7'R,8R,8'R) and (7R,7'S,8R,8'R) stereochemistry showed the strongest antibacterial activity against Listeria denitrificans and Bacillus subtilis, respectively. It was also found that (-)-virgatusin bearing (7S,7'R,8S,8'S) stereochemistry had strongest antifungal activity.

We investigated photoinduced charge separation occurring in a multicomponent colloidal system composed of oxide nanosheets of photocatalytically active niobate and photochemically inert clay and electron accepting methylviologen dications (MV2+). The inorganic nanosheets were obtained by exfoliation of layered hexaniobate and hectorite clay. The niobate and clay nanosheets were spatially separated in the colloidally dispersed state, and the MV2+ molecules were selectively adsorbed on the clay platelets. UV irradiation of the colloids led to electron transfer from the niobate nanosheets to the MV2+ molecules adsorbed on clay. The photoinduced electron transfer produced methylviologen radical cations (MV*+), which was characterized by high yield and long lifetime. The yield and stability of the MV*+ species were found to depend strongly on the clay content of the colloid: from a few mol % to approximately 70 mol % of the yield and several tens of minutes to more than 40 h of the lifetime. The contents of the niobate nanosheets and MV2+ molecules and the aging of the colloid also affected the photoinduced charge separation. In the absence of MV2+ molecules in the colloid, UV irradiation induced electron accumulation in the niobate nanosheets. The stability of the electron-accumulated state also depended on the clay content. The variation in the photochemical behavior is discussed in relation to the viscosity of the colloid.

Tetra-substituted tetrahydrofuran compounds were stereoselectively prepared from benzylic hemiacetal in the neutral condition by employing the simple reagent, H(2), and a Pd catalyst. The stereoselective conversion of benzylic hemiacetal to two different stereoisomers of the tetrasubstituted tetrahydrofuran compound was observed. One of these tetrahydrofuran compounds was converted to the virgatusin stereoisomer to estimate its antimicrobiological activity.

The benzyl mesylate was employed to construct the tetrasubstituted tetrahydrofuran lignan with avoiding Friedel-Crafts type of reaction. The optically pure 7,8-trans, 7',8'-trans, 7,7'-cis, and 8,8'-cis-virgatusin stereoisomers were synthesized. The enantiomeric excess was >>99%.

The effect of oxidation degree at the benzylic position of 2,3-dibenzyl-4-butanolide and 3,4-dibenzyltetrahydrofuran lignans on the antimicrobiological activity was examined. The highest oxidation degree at the benzylic position of 2,3-dibenzyl-4-butanolide gave the greatest activity, and 3,4-dibenzoyltetrahydrofuran showed the highest antifungal activity. The relationship between stereochemistry and activity was also examined. Both enantiomers of cis-matairesinol were synthesized for the first time, one of the cis-matairesinols showing antibacterial activity.

Antifungal activities of the optically pure (>99%ee) (-)- and (+)-virgatusin, a tetra-substituted tetrahydrofuran lignan, were tested. (-)-Virgatusin, which is a natural product, showed highest antifungal activity against Colletotrichum lagenarium. Research on its structure-activity relationship was also performed. It was shown that two methoxy groups on 9 and 9' positions and a 3,4-methylenedioxyphenyl group on the 7 position of virgatusin were essential for high fungal growth inhibition. The part on 7'-phenyl group was not essential for activity. The 7'-(4-methoxyphenyl) derivative showed higher activity than that of (-)-virgatusin.

The present work reports the results of a study on the growth kinetics and characterization of matrix polysaccharides in the cell walls of Lygodium japonicum prothallium grown in the presence of copper (Cu). When the prothallium was cultured in the media containing 0.2 mM or 0.4 mM CuSO(4), it showed a rapid accumulation of Cu with a maximum uptake of Cu measured in the cells up to 20 d of culture. The maximum rate of Cu uptake into the prothallium was greater for 0.4 mM Cu-treated cells (17.2 micromol g(-1) DW) than for 0.2 mM Cu-treated cells (3.2 micromol g(-1) DW). Cell walls were isolated from both untreated control and Cu-treated cells and then extracted sequentially with cyclohexane-trans-1,2-diaminetetra-acetate (CDTA), Na(2)CO(3), 1 M KOH, and 4 M KOH. The amount of pectin solubilized from 0.4 mM Cu-treated cell walls decreased to 53% of its level in the control, whereas the amount of hemicellulose solubilized from the Cu-treated cell walls represented 82% of that from control cell walls. When the polysaccharides were fractionated by anion-exchange chromatography into four carbohydrate components, considerable increases in fractions PI-3 and PII-3 eluted with 0.5 M NaCl were observed in CDTA-soluble (PI) and Na(2)CO(3)-soluble (PII) pectic polymers from Cu-treated cell walls. Fractions PI-3 and PII-3 were composed predominantly of uronic acid (more than 71% of total sugars). Approximately 66% of Cu within the cell walls was released from the 0.4 mM Cu-treated cells with the endo-pectate-lyase treatment, suggesting that most of the Cu that accumulated into the Lygodium prothallium is tightly bound to the homogalacturonan of the cell wall pectin.

Colloidally dispersed niobate nanosheets with the thickness of 1.8 nm and controlled mean lateral sizes of 0.15-7.8 mum were prepared and their liquid crystallinity was examined. The nanosheet colloids with different lateral sizes were obtained by exfoliation of single crystals of layered niobate K4Nb6O17 and subsequent ultrasonication. Naked-eye and microscope observations of the nanosheet colloids between crossed polarizers revealed liquid crystallinity of the sols characterized by birefringence as functions of the lateral sizes and concentration of the nanosheets. The nanosheet colloids with smaller lateral sizes (0.15-1.9 mum) varied from isotropic to biphasic (isotropic + liquid crystalline), and finally to fully liquid crystalline states as the colloid concentration increased. The phase transition concentrations (from isotropic to biphasic and biphasic to liquid crystalline) decreased with increasing aspect ratio (lateral-to-thickness ratio) of the nanosheets, almost in accordance with the prediction by Onsager theory, indicating that the liquid crystallinity is explained basically by excluded-volume effect between the nanosheets. On the other hand, the colloids with larger lateral sizes (6.2 and 7.8 mum) stably kept liquid crystalline state even at very low concentration (5.1 x 10-6 in volume fraction), which was much lower than that expected from the theory.

To assess the structural requirements for G(s) coupling by prostaglandin E receptors (EPs), the G(s)-coupled EP2 and G(i)-coupled EP3beta receptors were used to generate hybrid receptors. Interchanging of the whole i2 loop and its N-terminal half (i2N) had no effect on the binding of both receptors expressed in HEK293 cells. Agonist-induced cAMP formation was observed in wild type EP2 but not in the i2 loop- or i2N-substituted EP2. Wild type EP3beta left cAMP levels unaffected, whereas i2 loop- and i2N-substituted EP3 gained agonist-induced adenylyl cyclase stimulation. In EP2, the ability to stimulate cAMP formation was lost by mutation of Tyr(143) into Ala but retained by mutations into Phe, Trp, and Leu. Consistent with this observation, substitution of the equivalent His(140) enabled EP3beta to stimulate cAMP formation with the rank order of Phe > Tyr > Trp > Leu. The point mutation of His(140) into Phe was effective in another EP3 variant in which its C-terminal tail is different or lacking. Simultaneous mutation of the adjacent Trp(141) to Ala but not at the following Tyr(142) weakened the acquired ability to stimulate cAMP levels in the EP3 mutant. Mutation of EP2 at adjacent Phe(144) to Ala but not at Tyr(145) reduced the efficiency of agonist-induced cAMP formation. In Chinese hamster ovary cells stably expressing G(s)-acquired EP3 mutant, an agonist-dependent cAMP formation was observed, and pertussis toxin markedly augmented cAMP formation. These results suggest that a cluster of hydrophobic aromatic amino acids in the i2 loop plays a key role for G(s) coupling.