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Herein, we designed and synthesized a thermally stable carboxybetaine copolymer with a one- or three-carbon spacer between ammonium and carboxylate groups (CBMA1 and CBMA3) to create an anti-nonspecific adsorption surface with the ability to immobilize antibodies.

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Photo-iniferter reversible addition-fragmentation chain transfer (PI-RAFT) of N-vinylformamide (NVF) was demonstrated by using purple light. PNVFs with predetermined molar masses and narrow molar mass distributions were obtained. High RAFT chain-end fidelity was confirmed by MALDI-TOF and ESI-MS, and chain extension experiment. To demonstrate the potential of this approach, an original PVP-b-PNVF diblock copolymer was synthesized and characterized by aqueous SEC, A4F, and

Polyvinylamine-based double hydrophilic block copolymers are synthesised from RAFT polymerisation of N-vinylformamide.

The radical copolymerization on α-substituted fluoroalkyl acrylate (FA) monomer bearing C4, C6, and C8 as perfluoroalkyl (Rf) groups, as well as the variation of α-substituents, hydrogen, methyl, and chlorine with styrene was investigated. Q-e values and monomer reactivity ratio of FA monomers were estimated. When the alpha position of FA monomer of C6 as Rf group was changed from −H to −CH3, the e value decreased from 0.85 to 0.60. The substituent of −Cl resulted in an e value of 1.06. The Q values were also markedly changed. When the alpha position was changed from −H to −CH3, the Q value increased from 0.38 to 0.79. The substituent of −Cl resulted in a Q value of 2.90. The copolymer composition of α-substituted FA monomers with stearyl acrylate (C18A) was simulated. The obtained results revealed that a chlorine substituent at the alpha position emphasizes the polymerization which would contribute to a novel material design containing a fluorine side chain in a monomer structure.

In this paper, we provide a biography of Professor Rajendra Bhatia and discuss some of his influential mathematical works as one of the leading researchers in matrix analysis and linear algebra.

Stimuli-responsive materials have been actively researched over the past few decades. Among such materials, spiropyran is one of the most attractive compounds because the structure and polarity of the material are dramatically changed after photo irradiation, unlike other materials. In this work, we designed and synthesized a spiropyran derivative (SpMA) with a methacryloyl group on the nitrobenzene ring of a spiropyran skeleton. The UV spectra of the newly synthesized SpMA showed the photo-isomerization of spiropyran. The maximum absorption wavelength (λmax) of SpMA was 616 nm in n-hexane, a nonpolar solvent, although λmax of SpMA was 532 nm in methanol, a polar protic solvent, which resulted in an 84 nm blue-shift. SpMA was successfully polymerized by ruthenium (Ru)-catalyzed living radical polymerization. Poly(SpMA) (PSpMA) was then spin-coated on a PET substrate in order to control the surface properties of water repellency and cell adhesion. The water repellency was decreased approximately 10° under UV irradiation, because of the polarity change of PSpMA caused by photo-isomerization from the spiropyran (SP) type to the merocyanine (MC) type. In addition, NIH3T3 cells were spread only on 6% of the surface of the PSpMA thin film after UV irradiation compared with no UV irradiation. The polarity change of PSpMA by photo-isomerization is also believed to be the reason for this behavior. As a result, we successfully synthesized a photo-controllable cell culture scaffold.

A pharmacopoeia's core mission is to protect public health by creating and making available public standards to help ensure the quality of drugs. In recent years, pharmacopoeias around the world have harmonized their standards in the present context of globalized drug supply chains and markets. For example, the Pharmacopoeial Discussion Group has worked to harmonize excipient monographs and general chapters. In addition, the International Meeting of World Pharmacopoeias has been held by the WHO to discuss information exchange and international collaboration, among other topics. To contribute further to the protection of public health in the globalized drug market, we conducted a comparative study of the pharmacopoeias in Japan, Europe, and the United States. We aimed to examine current differences among the Japanese Pharmacopoeia, the European Pharmacopoeia, and the United States Pharmacopeia-National Formulary and to identify areas that require further collaboration among the three pharmacopoeias. In this study, we analyzed monographs and general chapters listed in the three pharmacopoeias. We identified the features of the monographs and general chapters listed in each pharmacopoeia, as well as differences across the pharmacopoeias. Moreover, on the basis of our findings, we suggest standards that require further collaboration among the pharmacopoeias in certain preferred areas. The comparison data produced by this study are expected to be used to develop strategies for future revisions of pharmacopoeias around the world.

Over the past few decades, techniques for improving the surface properties of various materials have been actively researched. In particular, water repellency is an important factor for controlling...

We have developed biocompatible scaffolds that enable cell fate control with visible light. The scaffolds are based on synthetic collagen-like polypeptide, poly(prolyl-hydroxyprolyl-glycyl) {poly(Pro-Hyp-Gly)} which has been used for cosmetics and other healthcare applications. Bioactive peptides were conjugated to the scaffolds via photoactivation reaction utilizing 488 nm visible light. In addition, the use of a photocleavable crosslinker enables dissociation of chemical moieties by 405 nm laser irradiation. The synthesis scheme enables optical control to attach and detach functional peptides in pre-patterned shapes. Using bone forming peptide (BFP), we demonstrate that calcium deposition by rat bone stromal cells can be directed on the scaffold. Using other signaling molecules and three-dimensional scaffolds, controlled differentiation of stem cells can be achieved by spatio-temporally specific irradiation of confocal microscope laser.

The Japanese Pharmacopoeia (JP) is an official document that defines the specifications, criteria, and standard test methods necessary to properly ensure the quality of medicines in Japan. To ensure the efficacy and safety of pharmaceutical products, it is essential to establish standards that ensure their quality. For this purpose, the JP aims to include all drugs that are important from the viewpoint of healthcare and medical treatment, and description of each monograph of medicine is maintained and improved so that those standards can be generally practiced. In addition, to play a key role as the official document in the field of pharmaceutical product quality, JP contents are enhanced by proactively introducing the latest scientific knowledge and technologies. As the international manufacturing of pharmaceutical products and their raw materials that are distributed in Japan is increasing, the JP has recently begun to promote the international harmonisation of pharmaceutical excipients and general tests through the Pharmacopoeial Discussion Group (PDG) and to swiftly implement the harmonised items in the JP. In addition, the JP will implement internationally harmonised concepts and specifications for pharmaceutical products, e.g., the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), to define the latest concepts of quality control for pharmaceutical products in the official document. We introduce the implementation of the latest scientific knowledge, technologies, and activities for international harmonisation of the JP.

Dengue virus (DENV) infection is a major cause of morbidity and mortality in Vietnam, and the incidence is higher and more consistent in the southern part of the country. This study investigated the circulation of DENV serotypes, viremia levels, immunological status, and cytokine levels, with disease severities among children infected in 2017 in Ho Chi Minh City, Southern Vietnam. Acute and convalescent serum samples were collected from clinically diagnosed dengue children. They were confirmed to have DENV infection by NS1 antigen, IgM and IgG ELISAs, virus isolation, and conventional and real-time RT-PCR. Measurement of 10 cytokine levels was performed in the serum samples. All the children were dengue IgM positive; 28% and 72% of them had primary and secondary DENV infections, respectively, whereas 54% of those with secondary infection were children with dengue with warning signs and with severe dengue. Any or mixed infection of the four serotypes of DENV RNA was detected in 58 children. Twenty DENV strains (DENV-1 = 16 and DENV-4 = 4) were isolated. Levels of IFN-γ, TNF-α, MCP-1, IL-10, and IL-6 were significantly higher in severe dengue cases. We report the predominance of DENV-1 over other serotypes in the 2017 dengue outbreak in Southern Vietnam. Our data showed that cytokine expressions were correlated with dengue pathogenesis and may help in identifying an effective therapeutic strategy., The American journal of tropical medicine and hygiene, 102(6), pp.1217-1225; 2020

Background Sri Lanka experienced its largest dengue outbreak in 2017 with more than 185,000 dengue cases including at least 250 fatalities. Objectives Our study aimed to characterize the clinical, immunological and virological features of confirmed dengue patients in Sri Lanka during the outbreak in 2017 when unusual manifestations of severe dengue were observed. Study design Sera from 295 patients who were admitted to Teaching Hospital Kandy, Kandy, Sri Lanka between March 2017- January 2018 were subjected to NS1 antigen, IgM and IgG ELISAs, virus isolation, conventional and real time RT-PCR and next generation sequencing. Results Primary and secondary infections were detected in 48.5 % and 51.5 % of the study population, respectively. Two hundred twenty five DENV strains were isolated (219 DENV-2, one DENV-3, two DENV-4, two mixed infections of DENV-2 and -3 and one mixed infection of DENV-2 and -4). Unusual and severe manifestations such as encephalitis, encephalopathy, liver failure, kidney failure, myocarditis, Guillain–Barre syndrome and multi-organ failure were noted in 44 dengue patients with 11 deaths. The viraemia levels in patients with primary infection and unusual manifestations were significantly higher compared to those in patients with secondary infection. A new clade of DENV-2 Cosmopolitan genotype strains was observed with the strains closely related to those from China, Malaysia, Indonesia, Singapore and Taiwan. Conclusions The new clade of DENV-2 cosmopolitan genotype observed in Sri Lanka in 2017 caused an unprecedented, severe dengue outbreak. The emergence of DENV-3 and DENV-4 in the 2017 outbreak might cause future outbreaks in Sri Lanka.

In the real Hilbert space of self-adjoint elements of the tensor product ${\mathbb {M}}_{m}\otimes {\mathbb {M}}_{n}$ , there are two natural cones besides the cone ${\mathfrak {P}}_{0}$ of positive semi-definite elements. The one is and the other is the cone ${\mathfrak {P}}_{-}$ , dual to ${\mathfrak {P}}_{+}$ with respect to the inner product. Then, ${\mathfrak {P}}_{+} \subset {\mathfrak {P}}_{0} \subset {\mathfrak {P}}_{-}.$ A weak order relation ≽ is introduced by Our interest is in finding bounds for the ratio | | |T| | |/| | |S| | | for S ≽T ≽ 0, where | | |⋅| | | is one of the operator norm, the trace norm, and the Hilbert-Schmidt norm.

In this study, we investigated severe fever with thrombocytopenia syndrome (SFTS) virus (SFTSV) infection in cats in Nagasaki, Japan. In total, 44 of 133 (33.1%) cats with suspected SFTS were confirmed to be infected with SFTSV. Phylogenetic analyses of SFTSV isolates from cats indicated that the main genotype in Nagasaki was J1 and that unique reassortant strains with J2 (S segment) and unclassified genotypes (M and L segments) were also present. There were no significant differences in virus growth in cell cultures or fatality in SFTSV-infected mice between the SFTSV strains that were isolated from recovered and fatal cat cases. Remarkably, SFTSV RNAs were detected in the swabs from cats, indicating that the body fluids contain SFTSV. To evaluate the risk of SFTSV infection when providing animal care, we further examined the seroprevalence of SFTSV infection in veterinarian staff members, 3 of 71 (4.2%) were seropositive for SFTSV-specific antibodies. Our results provide useful information on the possibility of using cats as sentinel animals and raised concerns of the zoonotic risk of catching SFTSV from animals.

Reproducing the features of the extracellular matrix is important for fabricating three-dimensional (3D) scaffolds for tissue regeneration. A collagen-like polypeptide, poly(Pro-Hyp-Gly), is a promising material for 3D scaffolds because of its excellent physical properties, biocompatibility, and biodegradability. In this paper, we present a novel photocrosslinked poly(Pro-Hyp-Gly) hydrogel as a 3D scaffold for simultaneous rat bone marrow stromal cell (rBMSC) encapsulation. The hydrogels were fabricated using visible-light photocrosslinking at various concentrations of methacrylated poly(Pro-Hyp-Gly) (20-50 mg/ml) and irradiation times (3 or 5 min). The results show that the rBMSCs encapsulated in the hydrogels survived 7 days of incubation. Calcium deposition on the encapsulated rBMSCs was assessed with scanning electron microscope observation, Alizarin Red S, and von Kossa staining. The most strongly stained area was observed in the hydrogel formed with 30 mg/ml of methacrylated poly(Pro-Hyp-Gly) with 5-min irradiation. These findings demonstrate that poly(Pro-Hyp-Gly) hydrogels support rBMSC viability and differentiation, as well as demonstrating the feasibility of using poly(Pro-Hyp-Gly) hydrogels as a cytocompatible, biodegradable 3D scaffold for tissue regeneration.

Severe fever with thrombocytopenia syndrome virus (SFTSV) can be transmitted between humans. We describe a case of severe fever with thrombocytopenia syndrome in which SFTSV RNA was detected in semen after its disappearance from serum. Our findings indicate possible sexual transmission of this emerging virus.

This study was conducted to find the burden of dengue virus (DENV) and Japanese encephalitis virus (JEV) among children under the age of 13, who presented with acute encephalitis syndrome at Mandalay Children Hospital in Myanmar in 2013. Molecular and serological investigations were performed on 123 cerebrospinal fluid (CSF) samples collected from these patients. By neutralization tests and/or virus isolation, four (3.3%) JEV- and one DENV-associated encephalitis cases (0.8%) were confirmed. Antibody titer against JEV Genotype 3 was the highest among the laboratory-confirmed JEV cases. One strain of DENV-1 with Genotype 1 was isolated from the CSF sample of the dengue encephalitis patient; this was similar to the virus circulating in the study area and neighboring countries. This study shows that flaviviruses are important pathogens causing encephalitis in Myanmar. Active disease surveillance, vector control,and vaccination programs should be enforced to reduce the morbidity and mortality caused by flavivirus encephalitis., The American journal of tropical medicine and hygiene, 100(3), pp.643-646; 2019

An element \(\mathbf{S}\) of the tensor product \({\mathbb M}_m\otimes {\mathbb M}_n\) is said to be separable if it admits a (separable) decomposition $$ \mathbf{S}\ =\ \sum _pX_p\otimes Y_p \quad \exists \ \ 0 \le X_p \in {\mathbb M}_m,\ \exists \ 0 \le Y_p \in {\mathbb M}_n. $$ This decomposition is not unique. We present some conditions on suitable norms of \(\mathbf{S}\) which guarantee its separability. Even when separability of \(\mathbf{S}\) is guaranteed by some method, its separable decomposition itself is difficult to construct. We present a general condition which makes it possible to find a way of an explicit separable decomposition.

Currently, the only available evidence for the efficacy of once-weekly 17.5 mg risedronate in preventing vertebral fractures was obtained in a 48-week study in Japan. We performed a 156-week prospective, longitudinal, observational study to determine the efficacy of the 17.5 mg risedronate in preventing vertebral fractures. We included Japanese patients with established osteoporosis who were older than 50 years and had radiographically confirmed vertebral fractures. The primary endpoint was the incidence of vertebral fractures every 24 weeks, with the final interval spanning 36 weeks. We also calculated the change in bone mineral density of the lumbar spine (L2-4 BMD) and urinary N-telopeptide of type I collagen (u-NTX), and assessed the incidence of adverse drug reactions and the drug adherence rate. Data from 241 patients were available for analysis of vertebral fracture prevention. The incidence rate of vertebral fractures decreased in a time-dependent manner (P = 0.0006; Poisson regression analysis). The risk ratio (fracture incidence per 100 person-years in the final 36 weeks versus that in the first 24 weeks) was 0.21 (95 % confidence interval 0.08-0.55). Compared to baseline values, L2-4 BMD increased by 6.41 % at 156 weeks, while u-NTX decreased by 36 % at 24 weeks and was maintained thereafter (P

Positivity of a $2\times2$ operator matrix $[\begin{smallmatrix}A&B\\B^{*}&C\end{smallmatrix}]\geq0$ implies $\sqrt{\|A\|\cdot\|C\|}\geq\|B\|$ for operator norm $\|\cdot\|$ . This can be considered as an operator version of the Schwarz inequality. In this situation, for $A,C\geq0$ , there is a natural notion of geometric mean $A\sharp C$ , for which $\sqrt{\|A\|\cdot\|C\|}\geq\|A\sharp C\|$ . In this paper, we study under what conditions on $A$ , $B$ , and $C$ or on $B$ alone the norm inequality $\sqrt{\|A\|\cdot\|C\|}\geq\|B\|$ can be improved as $\|A\sharp C\|\geq\|B\|$ .

We confirm a conjecture in Wocjan and Elphick (2013) [4] about a lower bound of the chromatic number of a graph.

An entomological surveillance of arboviruses was conducted in Myanmar in 2014. A total of 8357 Culex mosquito vectors were collected in the Mandalay area and virus isolation was done by using the mosquito cell line C6/36 E2. A total of eighteen strains of Culex flavivirus (CxFV) were isolated from Cx. tritaeniorhynchus, Cx. vishnui and Cx. fuscocephala. Like other insect-specific flaviviruses, CxFV can replicate only in mosquito cells but not in mammalian cells. These CxFV strains that were isolated in Japan from mosquitoes collected in Myanmar were closely related to the Wang Thong virus detected from Cx fusocephalus in Thailand and Cx.theileri flavivirus (CTFV) isolated from Cx. theileri mosquitoes in Portugal and Turkey. They encode a single open reading frame with 3357 amino acid residues. They have the characteristics of flaviviruses and have 95.62% amino acid identity with CTFV. This is the first report of CxFV in Myanmar with the characterized viral genome. This study illustrated that CxFV was circulating among the vectors of human pathogenic arboviruses in Myanmar but the impact of CxFV on other flaviviruses which are endemic in the study area still remains to be explored.

Encapsulation of stem cells into a three-dimensional (3D) scaffold is necessary to achieve tissue regeneration. Prefabricated 3D scaffolds, such as fibres or porous sponges, have limitations regarding homogeneous cell distribution. Hydrogels that can encapsulate cells such as animal-derived collagen gels need adjustment of the pH and/or temperature upon cell mixing. In this report, we fabricated a poly-ion complex (PIC) hydrogel of chitosan and succinylated poly(Pro-Hyp-Gly) and assessed its effect on cell viability after encapsulation of rat bone marrow stromal cells. PIC hydrogels were obtained successfully with a concentration of each precursor as low as 3.0-3.8 mg/ml. The maximum gelation and swelling ratios were achieved with an equal molar ratio (1:1) of anionic and cationic groups. Using chitosan acetate as a cationic precursor produced a PIC hydrogel with both a significantly greater gelation ratio and a better swelling ratio than chitosan chloride. Ammonium succinylated poly(Pro-Hyp-Gly) as an anionic precursor gave similar gelation and swelling ratios to those of sodium succinylated poly(Pro-Hyp-Gly). Cell encapsulation was also achieved successfully by mixing rat bone marrow stromal cells with the PIC hydrogel simultaneously during its formation. The PIC hydrogel was maintained in the culture medium for 7 days at 37°C and the encapsulated cells survived and proliferated in it. Although it is necessary to improve its functionality, this PIC hydrogel has the potential to act as a 3D scaffold for cell encapsulation and tissue regeneration. Copyright © 2015 John Wiley & Sons, Ltd.

Polyion complex (PIC) gel of poly(Pro-Hyp-Gly) was successfully fabricated by simply mixing polyanion and polycation derivatives of poly(Pro-Hyp-Gly), a collagen-like polypeptide. The polyanion, succinylated poly(Pro-Hyp-Gly), and the polycation, arginylated poly(Pro-Hyp-Gly), contain carboxy (pKa = 5.2) and guanidinium (pKa = 12.4) groups, respectively. Mixing the polyanion and the polycation at physiological pH (pH = 7.4) resulted in PIC gel. The hydrogel formation was optimum at an equimolar ratio of carboxy to guanidinium groups, suggesting that ionic interaction is the main determinant for the hydrogel formation. The hydrogel was successfully used for simultaneous rat bone marrow stromal cell encapsulation. The encapsulated cells survived and proliferated within the hydrogel. In addition, the cells exhibited different morphology in the hydrogel compared with cells cultured on a tissue culture dish as a two-dimensional (2D) control. At day one, a round morphology and homogeneous single cell distribution were observed in the hydrogel. In contrast, the cells spread and formed a fibroblast-like morphology on the 2D control. After three days, the cells in the hydrogel maintained their morphology and some of them formed multicellular aggregates, which is similar to cell morphology in an in vivo microenvironment. These results suggest that the PIC gel of poly(Pro-Hyp-Gly) can serve as a cytocompatible three-dimensional scaffold for stem cell encapsulation, supporting their viability, proliferation, and in vivo-like behavior.

The time and cost involved in bringing new drugs to the market hamper their approval. This problem is especially apparent in the case of renal diseases. Efficient drug research requires an a priori understanding of disease pathophysiology, target validation, rational and efficient drug discovery strategies and early testing of the physiological and pharmacological effects of the new agent in humans. Drug development initiated by academia benefits from international research networks and relies on internationally acceptable high-quality nonclinical data packages and bulk investigational drugs. Academics should, therefore, better understand pharmaceutical practice regulations and novel, efficient drug-development strategies. Many researchers remain unfamiliar with these areas and should collaborate with regulatory authorities to discover and validate surrogate markers for use in drug development, and to efficiently and effectively maximize the benefits and minimize the adverse effects of new drugs. The Japanese government and regulatory authorities have implemented a framework to encourage such collaborations; extension of this framework beyond its current reach is envisaged.

A densely defined, closed linear operator F in a Hilbert space is said to be idempotent if ran ( F ) ⊂ dom ( F ) and F · F = F . We show that such an idempotent operator is written as F = P ( P + Q ) - 1 / 2 · ( P + Q ) - 1 / 2 where P and Q are the orthoprojections to ran ( F ) and ker ( F ) , respectively. When F is bounded, this becomes F = P ( P + Q ) - 1 . Further we show that for any λ ≠ 0 the operator P + λ Q is invertible and F = P ( P + λ Q ) - 1 . In addition to the known results we present several descriptions of the norm ‖ F ‖ in terms of ‖ P + Q ‖ , ‖ ( P + Q ) - 1 ‖ or ‖ ( P - Q ) - 1 ‖ .

Water-soluble luminescent material was developed by introducing europium (Eu(III)) ions into the core of a star polymer. Living radical polymerization was used to obtain the star polymer. The strategy to introduce Eu(III) ions into the star polymer was studied using poly(methyl methacrylate) as an arm. The best Eu(III) ion introduction was obtained by simultaneous introduction, resulting in about 30 µmol/g-polymer, which needed only one step for synthesis. The utilization of a hydrophilic polymer such as poly(ethylene oxide) (PEO) as an arm produced a water-soluble star polymer. The Eu(III)-bearing PEO star polymer obtained in this study was water soluble and showed fluorescence. In addition, it was stable in water after 1 month. The Eu(III)-bearing star polymer exhibited luminescent properties under UV light irradiation with relatively high quantum yields of 60% in organic solution and 19% in aqueous solution. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2527–2535

Both innate and adaptive immunity are crucial for cancer immunosurveillance, but precise therapeutic equations to restore immunosurveillance in patients with cancer patients have yet to be developed. In murine models, α-galactosylceramide (α-GalCer)–loaded, tumor antigen–expressing syngeneic or allogeneic cells can act as cellular adjuvants, linking the innate and adaptive immune systems. In the current study, we established human artificial adjuvant vector cells (aAVC) consisting of human HEK293 embryonic kidney cells stably transfected with the natural killer T (NKT) immune cell receptor CD1d, loaded with the CD1d ligand α-GalCer and then transfected with antigen-encoding mRNA. When administered to mice or dogs, these aAVC-activated invariant NKT (iNKT) cells elicited antigen-specific T-cell responses with no adverse events. In parallel experiments, using NOD/SCID/IL-2rγcnull–immunodeficient (hDC-NOG) mouse model, we also showed that the human melanoma antigen, MART-1, expressed by mRNA transfected aAVCs can be cross-presented to antigen-specific T cells by human dendritic cells. Antigen-specific T-cell responses elicited and expanded by aAVCs were verified as functional in tumor immunity. Our results support the clinical development of aAVCs to harness innate and adaptive immunity for effective cancer immunotherapy. Cancer Res; 73(1); 62–73. ©2012 AACR.

Poly(ethylene glycol) (PEG)-armed Ru(II)-bearing microgel-core star polymer catalysts were used for the transfer hydrogenation of ketones. The star catalysts (Ru(II)-PEG Star) were one-pot synthesized by ruthenium-catalyzed living radical polymerization of poly(ethylene glycol) methyl ether methacrylate (PEGMA) and a sequential linking reaction with ethylene glycol dimethacrylate (1) and diphenylphosphinostyrene (2). The polymers efficiently and homogeneously reduced acetophenone into 1-phenylethanol in 2-propanol coupled with K2CO3 at a high yield, despite a low catalyst feed ratio to the substrate (Ru(II)/substrate=1/1000). Importantly, the catalytic activity was higher than that of the original RuCl2(PPh3)3, as well as that of similar polymer-supported Ru(II) catalysts, such as poly(methyl methacrylate)-armed star-, polystyrene gel- and random polymer-supported catalysts. Ru(II)-PEG Star is applicable to various substrates, including para-substituted aromatic, aliphatic and bulky ketones, where the activity of Ru(II)-PEG Star is is generally higher than that of RuCl2(PPh3)3. For example, the turnover frequency for 4-chloroacetophenone and cyclohexanone reached ∼1000 h−1, and the reduction rate of cyclopentanone and 3-methyl-5-heptanone was twice as high as that of RuCl2(PPh3)3. The star catalyst also showed high catalyst recyclability, independent of the substrate species. These features most likely arise from its unique reaction space, which consists of a ruthenium-embedded, hydrophobic microgel core surrounded by amphiphilic and polar PEGMA arms. Poly(ethylene glycol)-armed Ru(II)-bearing microgel star polymers, directly obtained from ruthenium-catalyzed living radical polymerization, were used as catalysts for transfer hydrogenation of ketones in 2-propanol. Owing to the good affinity of the core-reaction pocket and the surrounding arms to substrates and products, respectively, the star polymer catalysts homogeneously hydrogenated various ketones into the corresponding alcohols more efficiently than the other polymer-supported catalysts and the original ruthenium counterpart. The catalyst encapsulation into the unique microgel core further afforded efficient catalyst recycle and facile product recovery.

Oxidation of sec-alcohols was investigated with ruthenium-bearing microgel core star polymer catalysts [Ru(II)-Star]. The star polymer catalysts were directly prepared via RuCl2(PPh3)3-catalyzed living radical polymerization of methyl methacrylate (MMA), followed by the arm-linking reaction with ethylene glycol dimethacrylate (1) in the presence of diphenylphosphinostyrene (2). The Ru(II)-Star efficiently and homogeneously catalyzed the oxidation of 1-phenylethanol (S1) to give a corresponding ketone (acetophenone) in higher yield (92%) than the analogs of polymer-supported ruthenium complexes. Importantly, the star catalyst afforded high recycling efficiency in the oxidation. They held catalytic activity against three times catalysis even though they were recovered under air-exposure, whereas the conventional RuCl2(PPh3)3 lost the activity for same recycling procedure due to the deactivation by oxygen. The stability of the star catalysts during the recycle experiment was confirmed by detailed spectroscopic characterization. The star polymers also catalyzed oxidation for a wide range of sec-alcohols with aromatic and aliphatic groups. The substrate affinity was different from that with RuCl2(PPh3)3, suggesting the unique selectivity caused by the specific structure. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.

Collagens are widely used in medical applications, including as a scaffold for tissue regeneration. However, animal-derived collagens have several drawbacks, such as low thermal stability, nonspecific cell adhesion, antigenicity, and contamination with pathogenic substances. To overcome these problems, we chemically synthesized the collagen-like polypeptide, poly(prolyl-hydroxyprolyl-glycyl) (poly(Pro-Hyp-Gly)), which forms a collagen-like triple-helical structure and shows biodegradability and biocompatibility. Here, we designed a novel scaffold where fibronectin-derived Gly Arg-Gly-Asp-Ser (GRGDS) and Pro-His-Ser-Arg-Asn (PHSRN) peptides were simultaneously conjugated with poly(Pro-Hyp-Gly). We assessed cell adhesion and migration activities using NIH3T3 cells in the scaffold and stratification ofimmortalized rabbit corneal epithelial cells. Cell adhesion was enhanced in scaffolds with GRGDS, increased with increasing amounts of conjugated GRGDS, and was significantly higher than bovine type I atelocollagen but lower than bovine fibronectin. Interestingly, simultaneous conjugation of GRGDS and PHSRN synergistically enhanced cell migration. Scaffolds containing almost equal amounts of GRGDS and PHSRN showed significantly higher cell migration than bovine type I atelocollagen. Addition of free GRGDS completely inhibited cell migration on the scaffold, whereas addition of free PHSRN partially inhibited cell migration. These results suggest that GRGDS plays a definitive role, and PHSRN plays an additional role, in cell migration. Conjugation of GRGDS resulted in the same level of stratification of rabbit corneal epithelial cells compared with bovine type I atelocollagen and bovine fibronectin. Because the simultaneous conjugation of GRGDS and PHSRN on poly(Pro-Hyp-Gly) enhances cell adhesion, migration, and stratification, it may be a useful scaffold for tissue regeneration.

We study operator log-convex functions on $(0,\infty)$, and prove that a continuous nonnegative function on $(0,\infty)$ is operator log-convex if and only if it is operator monotone decreasing. Several equivalent conditions related to operator means are given for such functions. Operator log-concave functions are also discussed., Comment: 20 pages

Heparin is an extracellular matrix polysaccharide. It is widely employed as an anticoagulant and can be used to form an anticoagulant surface on various medical devices such as renal dialysis devices to prevent thrombosis. However, heparin may cause hemorrhage and thrombocytopenia. Moreover, commercially available heparin may be contaminated with viruses and allergens of animal origin, as it is derived mainly from porcine or bovine tissue. To avoid these problems, we prepared succinated and sulfonated enzymatically synthesized amylose (SucESA and SulfESA, respectively) and assessed their anticoagulant activity. SucESA and SulfESA inhibited factor Xa activity in normal human plasma to an equal extent. However, SucESA strongly inhibited thrombin activity, whereas SulfESA only inhibited it slightly. These results suggest that SucESA inhibits the activities of both factor Xa (or its upstream coagulation factors) and thrombin and that SulfESA inhibits only factor Xa activity (or that of its upstream coagulation factors). SucESA and SulfESA with a high degree of substitution strongly inhibited factor Xa and thrombin activity compared with those of the derivatives with a low degree of substitution, even when present in high concentrations. This suggests that the density of the anion group determines the degree of inhibition of factor Xa and thrombin activity. SucESA, which has a high molecular weight, inhibited thrombin activity to a greater degree than low molecular weight SucESA. Because SucESA and SulfESA inhibited both purified factor Xa and thrombin irrespective of the presence of antithrombin, it is suggested that SucESA and SulfESA inhibit via direct action with both enzymes.

There is a strong demand for antifouling surface. To create such antifouling surface, there are some approaches such as chemical reaction at the surface, coatings, internal additives, etc. We are developing polymers that can modify the surface property by easy treatments based on precise design and synthesis of the polymers. Biomedical synthetic materials, such as poly(ethylene terephthalate) (PET) and polypropylene (PP), are prone to adhesion of proteins, cells, and bacteria, causing functional failures in implants, artificial organs, catheters, and diagnostic devices, and increasing the risk of secondary infections. One of the promising answers is a hydrophilic polymer brush surface on which many polymer chains are connected in high density to inhibit adsorption of proteins and following adhesion of related biomolecules and cells. Such high density polymer brush is usually built by surface-initiated living radical polymerization through several chemical steps and polymers applied for medical devices are rather inert to chemical modification than inorganic materials. We thus created a new star shaped heteroarm polymer consisting of hydrophilic chains, as an antifouling block, and hydrophobic chains, as a substrate attaching block, for a biocompatible coating material, which is supposed to form polymer brush-like structure by simple coating procedure. The coating surface exhibited very good resistance to adhesion of platelets, bacteria, fibroblasts, and proteins although the corresponding linear polymer exhibited moderate resistance. This result indicates utilization of unique architecture of the star polymer is effective for building condensed polymer brush structure at the surface. Perfluoroalkyl group-containing polymer shows water/oil repellency. Although long perfluoroalkyl groups (longer than C8) exhibit high repellency, they can not be employed because of the environmental reason, nowadays. Shorter perfluoroalkyl groups (less than C8) give less effect to environment but they have less repellency. We thud designed block copolymers consisting of fluorine and non-fluorine containing monomers and evaluated the sequence effects as an internal additive to PP resin to improve oil repellency. By controlling fluorinated/non-fluorinated monomer sequence, the oil repellency of the fluorinated polymer-added polypropylene (PP) was dramatically improved compared to that modified with the randomly sequenced fluoropolymer. For instance, random copolymer consisting of 2-(perfluorohexyl)ethyl methacrylate (C6FMA) and stearyl methacrylate (StMA) gave slightly higher contact angle (13º) than that of non-additive PP (6º). Compared to the random copolymer, the diblock and triblock copolymer lead much higher contact angles (23º and 38º, respectively) when only 1wt% of the fluoropolymer was mixed into PP. This result indicates sequence regulation of fluorinated/non-fluorinated monomer in the fluoropolymer is effective to concentrate fluorine groups at the resin surface resulting in improvement of water/oil repellency.

In situ and time-resolved small-angle neutron scattering (SANS) was employed for the elucidation of star polymer formation mechanism via linking reaction of living linear polymers in ruthenium-catalyzed living radical polymerization. Here, methyl methacrylate (MMA) was first polymerized with R−Cl/RuCl2(PPh3)3/tribuylamine (n-Bu3N) initiating system, followed by the addition of ethylene glycol dimethacrylate (EGDMA: 3) as a linking agent. After the in situ addition of a small amount of 3 to living linear PMMA, the SANS analysis revealed the following three steps: (process II-1) formation of block copolymers (4) and competitive formation of the small star polymers via the linking reaction of 4 and 4; (process II-2) star−star linking of the small star polymers into star polymers and putting 4 into the core of the star polymers, leading to formation of the microgel-core star polymers; (process II-3) growth of the microgel-core star polymers (5) via placement of 4 into the microgel-core star polymers. Furtherm...