Effects of Curing Agents on the Adhesion of Epoxy Resin to Copper: A Density Functional Theory Study.

Epoxy resins are widely used adhesives in industrial fields. To use epoxy resin as an adhesive, it is necessary to mix the epoxy resin with a hardener. Hardeners have various functional groups and skeletons, and the properties of epoxy resins vary depending on the hardener. Although the adhesion of epoxy resins has been extensively studied using density functional theory (DFT) calculations, few studies have evaluated the effect of hardener molecules. Therefore, in this study, DFT calculations of adhesion energies and bonding structures on Cu (111) and Cu2O (111) surfaces are performed for model molecules of adducts of epoxy resin with hardeners having various functional groups and skeletons to evaluate the influence of the hardeners on the adhesion of epoxy resin to the metal surface. The adhesion energy to the Cu (111) surface is governed by the energy due to dispersion forces. Hardeners of the thiol type, which contain relatively heavy sulfur atoms, and hardeners with aromatic rings, displaying high planarity, enable the entire molecule to approach the metal surface, resulting in a relatively high adhesion strength. The calculations for the Cu2O (111) surface show the adhesion strength is more strongly influenced by interactions such as hydrogen bonds between the surface and adhesive molecules than by dispersion forces. Therefore, in adhesion to Cu2O (111), the benzylamine-epoxy adduct with hydrogen bonding and OH-π interactions with the surface, in addition to having a relatively flexible framework, shows a high adhesion strength.

Alström Syndrome: A Review Focusing on Its Diverse Clinical Manifestations and Their Etiology as a Ciliopathy.

Alström syndrome is a form of inherited obesity caused by a single gene abnormality and is inherited as an autosomal recessive trait. It is characterised by a variety of clinical manifestations, including progressive visual and hearing impairment, type 2 diabetes mellitus, dilated cardiomyopathy, and hepatic and renal dysfunction, in addition to obesity. Recent insights underline the pivotal involvement of the disease-associated gene (ALMS1) in cilia formation and function, leading to the classification of its clinical manifestations as a ciliopathy. This review delineates the diverse clinical indicators defining the syndrome and elucidates its pathological underpinnings.

Highly-purified rapidly expanding clones, RECs, are superior for functional-mitochondrial transfer.

BACKGROUND: Mitochondrial dysfunction caused by mutations in mitochondrial DNA (mtDNA) or nuclear DNA, which codes for mitochondrial components, are known to be associated with various genetic and congenital disorders. These mitochondrial disorders not only impair energy production but also affect mitochondrial functions and have no effective treatment. Mesenchymal stem cells (MSCs) are known to migrate to damaged sites and carry out mitochondrial transfer. MSCs grown using conventional culture methods exhibit heterogeneous cellular characteristics. In contrast, highly purified MSCs, namely the rapidly expanding clones (RECs) isolated by single-cell sorting, display uniform MSCs functionality. Therefore, we examined the differences between RECs and MSCs to assess the efficacy of mitochondrial transfer. METHODS: We established mitochondria-deficient cell lines (ρ0 A549 and ρ0 HeLa cell lines) using ethidium bromide. Mitochondrial transfer from RECs/MSCs to ρ0 cells was confirmed by PCR and flow cytometry analysis. We examined several mitochondrial functions including ATP, reactive oxygen species, mitochondrial membrane potential, and oxygen consumption rate (OCR). The route of mitochondrial transfer was identified using inhibition assays for microtubules/tunneling nanotubes, gap junctions, or microvesicles using transwell assay and molecular inhibitors. RESULTS: Co-culture of ρ0 cells with MSCs or RECs led to restoration of the mtDNA content. RECs transferred more mitochondria to ρ0 cells compared to that by MSCs. The recovery of mitochondrial function, including ATP, OCR, mitochondrial membrane potential, and mitochondrial swelling in ρ0 cells co-cultured with RECs was superior than that in cells co-cultured with MSCs. Inhibition assays for each pathway revealed that RECs were sensitive to endocytosis inhibitor, dynasore. CONCLUSIONS: RECs might serve as a potential therapeutic strategy for diseases linked to mitochondrial dysfunction by donating healthy mitochondria.

Synthesis and Characterization of 1-Hydroxy-4,5-arene-Fused Tropylium Derivatives.

The properties of 1-hydroxy-4,5-arene-fused tropyliums were assessed based on experimental and theoretical investigations. An X-ray crystallographic analysis revealed a decrease of bond alternation in the seven-membered ring of 1-hydroxy-4,5-benzotropylium derivatives compared with that of the parent 4,5-benzotropones, which is indicative of an increase in aromaticity upon protonation. NICS and AICD calculations also supported the increased aromaticity of 1-hydroxy-4,5-arene-fused tropylium. The pKa values for a series of 1-hydroxy-4,5-arene-fused tropylium derivatives were also determined.

Synthesis of 4,5-Benzotropone π Complexes of Iron, Rhodium, and Iridium and Their Potential Use in Catalytic Borrowing-Hydrogen Reactions.

The syntheses of rhodium, iridium, and iron π complexes bearing 4,5-benzotropone ligands are reported. X-ray crystallographic analyses revealed that a tropone core coordinates to a metal center in a η4 manner with a tub-form geometry. Some of the benzotropone π complexes exhibited catalytic activity for N-alkylation of aniline by borrowing hydrogen.

Evaluation and improvement of storage stability of astaxanthin isomers in oils and fats.

Astaxanthin Z-isomers potentially have greater bioavailability and biological activity than (all-E)-astaxanthin. However, the stability of the Z-isomers is lower than the all-E-isomer, which is a serious problem affecting its practical use. In this study, we investigated the impacts of different suspension media (oils and fats) and additives on astaxanthin isomer stability and identified suitable ones for astaxanthin stabilization. The evaluations showed that several vegetable oils and antioxidants significantly improved astaxanthin isomer stability, e.g., when soybean and sunflower oils were used as the suspension medium, astaxanthin isomers were hardly degraded; however the total Z-isomer ratio decreased from ~80% to ~50% during 6-week storage at 30 °C. Moreover, it was revealed that (9Z)-astaxanthin showed higher stability than the 13Z- and 15Z-isomers. Hence, to maintain astaxanthin concentration and the Z-isomer ratio over long periods, it is important to use suitable suspension mediums and antioxidants, and select a Z-isomerization method that increases (9Z)-astaxanthin ratio.

Z-Isomers of Astaxanthin Exhibit Greater Bioavailability and Tissue Accumulation Efficiency than the All-E-Isomer.

The purpose of the present study was to clarify the differences in the bioavailability and tissue accumulation efficiency between (all-E)- and (Z)-astaxanthin. Astaxanthin with a high proportion of the Z-isomer (especially rich in the 9Z- and 13Z-isomers) was prepared from (all-E)-astaxanthin by thermal treatment and solid-liquid separation. The all-E-isomer- or Z-isomer-rich diet was fed to male rats for 2 weeks. After the feeding period, blood and tissue samples were collected, and their astaxanthin levels were evaluated. The Z-isomer-rich astaxanthin diet resulted in higher levels of astaxanthin in blood and many tissues (in particular, skin, lung, prostate, and eye) compared to the all-E-isomer-rich diet. Moreover, the Z-isomer-rich diet enhanced the level of the 13Z-isomer in blood and tissues rather than that of the 9Z-isomer. These results strongly supported that astaxanthin Z-isomers have greater bioavailability and tissue accumulation efficiency than the all-E-isomer. Moreover, (13Z)-astaxanthin would have higher bioavailability and tissue accumulation than the other isomers.

Astaxanthin Z-isomer-rich diets enhance egg yolk pigmentation in laying hens compared to that in all-E-isomer-rich diets.

The effects of feeding diets containing astaxanthin with different Z-isomer ratios to laying hens on egg qualities, such as astaxanthin concentration in egg yolk and yolk color, were investigated. As the astaxanthin source, a natural microorganism Paracoccus carotinifaciens was used. Astaxanthin with different Z-isomer ratios was prepared by thermal treatment with different conditions and then added to the basal diet at a final astaxanthin concentration of 8 mg/kg. We found that, as the Z-isomer ratios of astaxanthin in the diet increased, the astaxanthin concentration in egg yolk and the yolk color fan score also increased significantly. Importantly, feeding a 50.6% Z-isomer ratio diet increased astaxanthin concentration in egg yolk by approximately fivefold and the color fan score by approximately 2 compared to that in hens fed an all-E-isomer-rich diet. Moreover, we showed that feeding Z-isomer-rich astaxanthin to laying hens increased plasma astaxanthin concentration by more than five times in comparison to that in hens fed an all-E-isomer-rich diet. These results indicate that Z-isomers of astaxanthin have higher bioavailability than that of the all-E-isomer and thus they exhibit greater egg yolk-accumulation efficiency.

Effect of astaxanthin-rich extract derived from Paracoccus carotinifaciens on the status of stress and sleep in adults.

This study investigated the effect of a dietary supplement containing astaxanthin-rich extract derived from Paracoccus carotinifaciens (astaxanthin supplement) on the status of stress and sleep in individuals aged 20-64 years. Twenty-five subjects orally administered 12 mg astaxanthin/day of astaxanthin supplement for 8 weeks (astaxanthin group) and 29 subjects given a placebo (placebo group) were evaluated with Profile of Mood States 2nd Edition for stress and Oguri-Shirakawa-Azumi Sleep Inventory for Middle-aged and Aged version for sleep. We did not observe any significant intergroup differences in the stress and sleep. A subgroup analysis was performed after dividing the subjects into two groups: those who scored >65 and those who scored ≤65 in the "Depression-Dejection" dimension of Profile of Mood States 2nd Edition. The sleep of subjects who scored >65 ("Depression-Dejection") showed significant improvement in the astaxanthin group compared with the placebo group, whereas no significant improvement was observed in stress and the other subjects. Our results indicate that people who tend to be strongly depressed may experience improved sleep after ingesting astaxanthin supplement. On the basis of the parameters tested, administration of astaxanthin supplement was not associated with any problems related to safety. Clinical registration: This study has been registered at the University Hospital Medical Information Network (https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000038619) on August 24, 2018 as "A study to evaluate the effect of intake of astaxanthin on the status of stress and sleep in adults," Identification No. UMIN000033863.

Recurrent Erythema Nodosum in a Child with a SHOC2 Gene Mutation.

We report the case of a 6-year-old male who developed recurrent erythema nodosum (EN) at the age of 3 years. The patient exhibited hypertelorism, low-set ears, micrognathia, moderate intellectual disability, thin long fingers, loose anagen hair, and prominent palmoplantar wrinkles. A heterozygous single nucleotide variant in the SHOC2 gene (c.4 A > G, p.S2G) was identified. Patients with a SHOC2 mutation exhibit a unique combination of ectodermal abnormalities including darkly pigmented skin and loose anagen hair. This report is the first to describe EN in a patient with SHOC2 mutation, and to examine the patient's hair using scanning electron microscopy. We hypothesize that the RAS/MAPK pathway is associated with the pathogenesis of cutaneous lesions in patients with SHOC2 mutations via autoinflammation and disturbance of epithelial stem cells.

Natural histories of patients with Wolf-Hirschhorn syndrome derived from variable chromosomal abnormalities.

Wolf-Hirschhorn syndrome (WHS) is a subtelomeric deletion syndrome affecting the short arm of chromosome 4. The main clinical features are a typical craniofacial appearance, growth deficiency, developmental delays, and seizures. Previous genotype-phenotype correlation analyses showed some candidate regions for each clinical finding. The WHS critical region has been narrowed into the region 2 Mb from the telomere, which includes LETM1 and WHSC1; however, this region is insufficient to cause "typical WHS facial appearance". In this study, we identified 10 patients with a deletion involving 4p16.3. Five patients showed pure terminal deletions and three showed unbalanced translocations. The remaining patients showed an interstitial deletion and a suspected inverted-duplication-deletion. Among 10 patients, one patient did not show "typical WHS facial appearance" although his interstitial deletion included LETM1 and WHSC1. On the other hand, another patient exhibited "typical WHS facial appearance" although her small deletion did not include LETM1 and WHSC1. Instead, FGFRL1 was considered as the candidate for this finding. The largest deletion of 34.7 Mb was identified in a patient with the most severe phenotype of WHS.

Effects of astaxanthin-rich dried cell powder from Paracoccus carotinifaciens on carotenoid composition and lipid peroxidation in skeletal muscle of broiler chickens under thermo-neutral or realistic high temperature conditions.

Thirty-two 15-day old broiler chicks (Chunky strain ROSS 308) were randomly divided into four treatments in a 2 × 2 factorial design. The main factors were diet (basal diet or basal diet supplemented with 0.15% astaxanthin-rich dried cell powder (Panaferd-P [astaxanthin 30 ppm]) and ambient temperature (thermo-neutral [25 ± 1°C] or high [35 ± 1°C for 6 hr]). Dietary supplementation with Panaferd-P did not affect growth performance, though high ambient temperature decreased feed intake and the weight of breast tender muscle, liver, and heart. High ambient temperature also decreased redness in both breast and leg muscles of chickens, while Panaferd-P increased redness and yellowness of breast and leg muscles of chickens. Panaferd-P increased Paracoccus carotinifaciens-derived pigments (i.e., adonixanthin, astaxanthin, adonirubin, and cantaxanthin) as well as corn-derived pigments such as zeaxanthin and lutein in breast and leg muscles. High ambient temperature increased the malondialdehyde (MDA) concentration in breast muscle, while Panaferd-P decreased the MDA concentration in breast muscle under both temperature conditions. Our results suggest that dietary supplementation with Panaferd-P increases muscle carotenoid content, the redness and yellowness of meat and decreases the muscle MDA concentration in broiler chickens kept under thermo-neutral or high ambient temperature conditions.

Structures of Yellow Xanthophylls and Metabolism of Astaxanthin in the Prawn Penaeus japonicus.

The dried powder of Paracoccus carotinifaciens (PANAFERD-AX®) contains (3S,3'S)-astaxanthin as a major carotenoid. Administration of PANAFERD-AX® for pigmentation of the prawn Penaeus japonicus was examined. Total carotenoid contents in the carapace, muscle, and head of the prawn were dose-dependently increased depending on the amount of PANAFERD-AX® administered. Furthermore, not only the amounts of astaxanthins (astaxanthin diester, astaxanthin monoester, and free astaxanthin) but also the amounts of yellow xanthophylls, isoastaxanthin (1), 5,6-dihydropenaeusxanthin (2), penaeusxanthin (3), tetrahydroxypirardixanthin (4), and curstaxanthin (5), were dose-dependently increased with the administration of PANAFERD-AX®. 5,6-Dihydropenaeusxanthin (2) and penaeusxanthin (3) are new carotenoids isolated from the prawn P. japonicus. These structures were determined to be (3R,4S,5R,6R,6'S)-5,6-dihydro-3,4,4'- trihydroxy-ß,ε-caroten-3'-one (2) and (3R,4S,6'S)-3,4,4'-trihydroxy-ß,ε-caroten-3'-one (3) by UV/vis, ESI TOF MS, 1H NMR, and CD spectral data. The metabolism of astaxanthin to these yellow xanthophylls in the prawn was discussed.

Total Synthesis of Polycavernosides A and B, Two Lethal Toxins from Red Alga.

Polycavernosides A and B are glycosidic macrolide natural products isolated as the toxins causing fatal human poisoning by the edible red alga Gracilaria edulis (Polycavernosa tsudai). Total synthesis of polycavernosides A and B has been achieved via a convergent approach. The synthesis of the macrolactone core structure is highlighted by the catalytic asymmetric syntheses of the two key fragments using hetero-Diels-Alder reaction and Kiyooka aldol reaction as the key steps, their union through Suzuki-Miyaura coupling, and Keck macrolactonization. Finally, glycosylation with the l-fucosyl-d-xylose unit and construction of the polyene side chain through Stille coupling completed the total synthesis of polycavernosides A and B.

Toward the Total Synthesis of Amphidinolide N: Synthesis of the C8-C29 Fragment.

A synthesis of the C8-C29 fragment of amphidinolide N, a potent cytotoxic macrolide isolated from the marine dinoflagellate Amphidinium sp., has been achieved. The key features of the synthesis involve a convergent union of the C9-C15 and C16-C29 fragments by Steglich esterification and the construction of a pyran unit through a Tebbe methylenation/ring-closing metathesis sequence.

Contrast adaptation to luminance and brightness modulations.

Perceptual brightness and color contrast decrease after seeing a light temporally modulating along a certain direction in a color space, a phenomenon known as contrast adaptation. We investigated whether contrast adaptation along the luminance direction arises from modulation of luminance signals or apparent brightness signals. The stimulus consisted of two circles on a gray background presented on a CRT monitor. In the adaptation phase, the luminance and chromaticity of one circle were temporally modulated, while the other circle was kept at a constant luminance and color metameric with an equal-energy white. We employed two types of temporal modulations, namely, in luminance and brightness. Chromaticity was sinusoidally modulated along the L-M axis, leading to dissociation between luminance and brightness (the Helmholtz-Kohlrausch effect). In addition, luminance modulation was minimized in the brightness modulation, while brightness modulation was minimized in the luminance modulation. In the test phase, an asymmetric matching method was used to measure the magnitude of contrast adaptation for both modulations. Our results showed that, although contrast adaptation along the luminance direction occurred for both modulations, contrast adaptation for luminance modulation was significantly stronger than that for the brightness modulation regardless of the temporal frequency of the adaptation modulation. These results suggest that luminance modulation is more influential in contrast adaptation than brightness modulation.

Progress toward the Total Synthesis of Goniodomin A: Stereocontrolled, Convergent Synthesis of the C12-C36 Fragment.

Goniodomin A is a marine polyether macrolide natural product isolated from the dinoflagellate Alexandrium hiranoi. In this paper, we report stereocontrolled, convergent synthesis of a fully functionalized C12-C36 fragment of goniodomin A. The synthesis of the C12-C25 vinylstannane involved a Wittig reaction and a reductive cycloetherification for the construction of the dihydropyran ring. The C26-C36 thioester was synthesized via a Nozaki-Hiyama-Kishi reaction of an aldehyde and an iodoalkyne, the former of which was easily prepared from (R)-malic acid as a chiral source by taking advantage of substrate-controlled diastereoselective reactions. Finally, a palladium-catalyzed coupling of the C12-C25 vinylstannane and the C26-C36 thioester completed the synthesis of the target compound.

Modulation of Energy Conversion Processes in Carbonaceous Molecular Bearings.

The energetics and photodynamics of carbonaceous molecular bearings with discrete molecular structures were investigated. A series of supramolecular bearings comprising belt-persistent tubular cycloarylene and fullerene molecules accepted photonic stimuli to afford charge-separated species via a photoinduced electron transfer process. The energy conversion processes associated with the photoexcitation, however, differed depending on the molecular structure. A π-lengthened tubular molecule allowed for the emergence of an intermediary triplet excited state at the bearing, which should lead to an energy conversion to thermal energy. On the other hand, low-lying charge-separated species induced by an endohedral lithium ion in fullerene enabled back electron transfer processes to occur without involving triplet excited species. The structure-photodynamics relationship was analyzed in terms of the Marcus theory to reveal a large electronic coupling in this dynamic supramolecular system.

Graphene oxide-Li(+)@C60 donor-acceptor composites for photoenergy conversion.

An ionic endohedral metallofullerene (Li(+)@C60) with mild hydrophilic nature was combined with graphene oxide (GO) to construct a donor-acceptor composite in neat water. The resulting composite was characterised by UV-Vis and Raman spectroscopy, powder X-ray diffraction, dynamic light scattering measurements and transmission electron microscopy. Theoretical calculations (DFT at the B3LYP/6-31(d) level) were also utilized to gain further insight into the composite formation. As detected by electron paramagnetic resonance spectroscopy, photoexcitation of the GO-Li(+)@C60 composite results in electron transfer from GO to the triplet excited state of Li(+)@C60, leading to photocurrent generation at the OTE/SnO2 electrode.