Insulated π-Conjugated Azido Scaffolds for Stepwise Functionalization via Huisgen Cycloaddition on Metal Oxide Surfaces.

In organic-inorganic hybrid devices, fine interfacial controls by organic components directly affect the device performance. However, fabrication of uniformed interfaces using π-conjugated molecules remains challenging due to facile aggregation by their strong π-π interaction. In this report, a π-conjugated scaffold insulated by covalently linked permethylated α-cyclodextrin moiety with an azido group is synthesized for surface Huisgen cycloaddition on metal oxides. Fourier-transformed infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy confirm the successful immobilization of the insulated azido scaffold on ZnO nanowire array surfaces. Owing to the highly independent immobilization, the scaffold allows rapid and complete conversion of the surface azido group in Huisgen cycloaddition reactions with ethynyl-terminated molecules, as confirmed by FT-IR spectroscopy monitoring. Cyclic voltammetry analysis of modified indium tin oxide substrates shows the positive effects of cyclic insulation toward suppression of intermolecular interaction between molecules introduced by the surface Huisgen cycloaddition reactions. The utility of the scaffold for heterogeneous catalysis is demonstrated in electrocatalytic selective O2 reduction to H2O2 with cobalt(II) chlorin modified fluorine doped tin oxide electrode and photocatalytic H2 generation with iridium(III) dye-sensitized Pt-loaded TiO2 nanoparticle. These results highlight the potential of the insulated azido scaffold for a stepwise functionalization process, enabling precise and well-defined hybrid interfaces.

Cyclic Sesquiterpene-Flavanone [4+2] Hybrids, Syzygioblanes A-C, Found in an Indonesian Traditional Medicine, "Jampu Salo" (Syzygium oblanceolatum).

A plant used in an Indonesian traditional herbal medicine as a diabetes treatment and known locally as "Jampu Salo" was collected on Sulawesi Island, Indonesia. It was identified as Syzygium oblanceolatum (C. B. Rob.) Merr. (Myrtaceae) and found for the first time in Sulawesi; it was previously reported only in the eastern Philippines and Borneo. A phytochemical study of S. oblanceolatum led to the isolation of three unprecedented meroterpenoids, syzygioblanes A-C (1-3, respectively). These compounds might be biosynthesized through [4+2] cycloaddition of various germacrane-based cyclic sesquiterpenoids with the flavone desmethoxymatteucinol to form a spiro skeleton. The unique and complex structures were elucidated by microcrystal electron diffraction analysis in addition to general analytical techniques such as high-resolution mass spectrometry, various nuclear magnetic resonance methods, and infrared spectroscopy. Synchrotron X-ray diffraction and calculations of electronic circular dichroism spectra helped to determine the absolute configurations. The newly isolated compounds exhibited collateral sensitivity to more strongly inhibit the growth of a multidrug resistant tumor cell line compared to a chemosensitive tumor cell line.

Development of Air Cell System Following Canal Wall Up Mastoidectomy for Pediatric Cholesteatoma.

Background: The development of temporal bone pneumatization is related to the postnatal middle ear environment, where the development of air cells is suppressed with otitis media in early childhood. However, whether air cell formation restarts when mastoidectomy is performed during temporal bone pneumatization remains unclear. Herein, we evaluated temporal bone pneumatization after canal wall up (CWU) tympanomastoidectomy for middle ear cholesteatoma in children. Methods: In total, 63 patients, including 29 patients with congenital cholesteatoma (CC) and 34 patients with acquired cholesteatoma (AC), were assessed using a set of pre- and postoperative computed tomography images. The air cells of the temporal bone were divided into five areas: periantral (anterior), periantral (posterior), periantral (medial), peritubal, and petrous apex. The number of areas with air cells before and after surgery was compared to evaluate temporal bone pneumatization after surgery. Results: A total of 63 patients, comprising 29 with CC and 34 with AC (pars flaccida; 23, pars tensa; 7, unclassified; 4), were evaluated. The median age of patients (18 males and 11 females) with CC was 5.0 (range, 2-15 years), while that of the AC group (23 males and 11 females) was 8 (range, 2-15 years). A significant difference in air cell presence was identified in the CC and AC groups after surgery (Mann-Whitney U, p < 0.001 and p = 0.003, respectively). Between the two groups, considerably better postoperative pneumatization was observed in the CC group. A correlation between age at surgery and gain of postoperative air cell area development was identified in the CC group (Spearman's rank-order correlation coefficient, r = -0.584, p < 0.001). In comparison with the postoperative pneumatization rate of each classified area, the petrous apex area was the lowest in the CC and AC groups. Conclusions: Newly developed air cells were identified in the temporal bones after CWU mastoidectomy for pediatric cholesteatoma. These findings may justify CWU tympanomastoidectomy, at least for younger children and CC patients, who may subsequently develop air cell systems after surgery.

Roles of mitochondrial alternative oxidase in photosynthetic electron transport in illuminated leaves of Arabidopsis thaliana at low temperature.

ATP-uncoupling alternative oxidase (AOX) in the plant respiratory chain is often induced under stress conditions such as low temperature (LT). The importance of AOX in photosynthesis has been examined, and leaves having larger amounts of AOX tended to show larger decrease in photosynthetic electron transport rate (ETR) by AOX inhibition. However, the details were not clarified. Here, we used three ecotypes of Arabidopsis thaliana which differed in AOX amounts and their responses to LT, and examined whether AOX amount was related to the degree of decrease in ETR by AOX inhibition. In Tiv-0, which originates from a warmer site, grown at high temperature (HT), AOX inhibition decreased ETR, but not in the other ecotypes. LT treatment significantly increased ETR and AOX, especially in Bur-0, but AOX inhibition did not decrease ETR in LT plants of any ecotype. AOX inhibition significantly increased the non-regulated energy dissipation in photosystem II (PSII), Y(NO), and decreased the maximal quantum yield of PSII, Fv/Fm, especially in LT plants. Since AOX inhibition did not affect the parameters of PSI, AOX inhibition may directly affect the reaction center of PSII in LT plants.

Changes in coagulation factor XIII activity during resuscitation for hemorrhagic shock.

Objective: Little is known about the coagulation activity of factor XIII (FXIII) during resuscitation for hemorrhagic shock and the effects of plasma transfusions. We performed a single-center observational study to evaluate the changes in FXIII activity during resuscitation for hemorrhagic shock. Patient and Methods: Twenty-three adult patients with hemorrhagic shock were enrolled in this study. Blood samples were drawn upon arrival (T1), at the time of hemostasis completion (T2), and on day 2 (T3). Baseline and changes in FXIII activity and the proportion of patients with adequate levels of FXIII activity (FXIII activity >70%) were evaluated. The effects of plasma transfusion on these parameters were also investigated. Results: At T1, the median (interquartile range) FXIII activity was 53% (47-85%), which did not increase (T1 vs. T3: 53% [47-85%] vs. 63% [52-70%], P=0.8766). The proportion of patients with adequate FXIII activity decreased throughout the resuscitation period (T1, T2, and T3: 30, 34, and 21%, respectively). Plasma transfusion did not affect FXIII activity (T1 vs. T2, 66.4% [23.4] vs. 70.0% [16.2%], P=0.3956; T2 vs. T3, 72.0% [19.5] vs. 63.5% [8.6%], P=0.1161) or the proportion of adequate levels of FXIII activity at 44% at T2 and 27% at T3. Conclusion: FXIII activity is low during the early phase of a hemorrhagic shock. Even with plasma transfusion, FXIII levels were not adequately maintained throughout resuscitation.

High Power Density of a Hydrogen Peroxide Fuel Cell Using Cobalt Chlorin Complex Supported on Carbon Nanotubes as a Noncorrosive Anode.

Hydrogen peroxide fuel cells (HPFCs) have attracted much attention due to their simple one-compartment structures and high availability under harsh conditions such as an anaerobic environment; however, catalysis improvement is strongly demanded for both anodes and cathodes in terms of activity and durability. Herein, we report the high catalytic activity of CoII chlorin [CoII(Ch)] for hydrogen peroxide (H2O2) oxidation with a low overpotential (0.21 V) compared to that of the CoII phthalocyanine and CoII porphyrin complexes, which have previously been reported as active anode catalysts. Linear sweep voltammograms and differential pulse voltammograms of the CoII complexes (CoIIL) and the corresponding ligands clearly showed that the CoIIIL species are the active species for H2O2 oxidation. Then, one-compartment HPFCs were constructed with CoII(Ch) supported on multiwalled carbon nanotubes (CNTs) as the anode together with FeII3[CoIII(CN)6]2 supported on CNTs as the cathode. The maximum power density of the HPFCs reached 151 µW cm-2 with an open circuit potential of 0.33 V when the coverage of CNT surfaces with CoII(Ch) exceeded ∼60% at the anode.