Non-Fouling Character of Poly[2-(methacryloyloxy)ethyl Phosphorylcholine]-Modified Gold Surfaces Fabricated by the 'Grafting to' Method: Comparison of its Protein Resistance with Poly(ethylene glycol)-Modified Gold Surfaces.

Poly[2-(methacryloyloxy)ethyl phosphorylcholine] -modified gold surfaces, which have been newly prepared by a 'grafting to' method using a series of monosulfanyl-terminated PMPC, are characterized by protein adsorption experiments based on surface plasmon resonance spectroscopy and ellipsometry measurements. The extent of BSA adsorption on PMPC-modified surfaces was systematically reduced for thicker PMPC layers, thus the number of MPC units on the gold surface appears to be an important factor for the excellent protein resistance offered by PMPC-modified gold surfaces fabricated by the 'grafting to' method, which is sharp contrast to that of PEG tethered chains.

Efficient inhibition of interfacial nonspecific interaction to create practically utilizable high ferritin-response immunolatex.

Immunolatex particles (LAmP-s), which were prepared by covalently co-immobilizing antiferritin and a mixture of pentaethylenehexamine-ended poly(ethylene glycol) (N6-PEG) of two different chain lengths onto the surface of polystyrene submicroparticles, were formulated with various antiferritin loads. Following the quantification of the bound antiferritin, as well as the differentiation of the physically adsorbed antiferritin from chemically bound antiferritin, using the copper reduction/bicinchoninic acid reaction (the Micro BCA method), dynamic light scattering (DLS) and electrophoretic mobility (mu(e)) measurements were performed to characterize the size, homogeneity, and surface charge of the complex. Compared to the control immunolatex particles, which were prepared similarly but traditionally using bovine serum albumin (BSA) as a blocking agent (LAB-s), the LAmP-s complex showed a difference only in the surface charge property, because of the altered surface treatment in the case of the LAmP-s (PEGylation) and LAB-s complexes (BSA covering).

Studies on the adsorption property and structure of polyamine-ended poly(ethylene glycol) derivatives on a gold surface by surface plasmon resonance and angle-resolved X-ray photoelectron spectroscopy.

The adsorption properties and structure of polyamine-ended poly(ethylene glycol) (PEG) derivatives on a flat gold surface were studied by means of surface plasmon resonance (SPR) and X-ray photoelectron spectroscopy (XPS) using PEG(5k)-block-poly[2-(N,N-dimethylamino)ethyl methacrylate](7.5k) [PEG-b-PAMA(5k/7.5k)] and pentaethylenhexamine-ended PEG(5k) [N6-PEG(5k)], which had 48 and 6 amino groups at the omega-end, respectively.

pH-sensitive radical-containing-nanoparticle (RNP) for the L-band-EPR imaging of low pH circumstances.

For the imaging of low pH circumstances in vivo, a pH-sensitive radical-containing-nanoparticle (RNP), which has an intense electron paramagnetic resonance (EPR) signal, was designed and developed using a self-assembling amphiphilic block copolymer (PEG-b-PCTEMPO) composed of a hydrophilic poly(ethylene glycol) (PEG) segment and a hydrophobic poly(chloromethylstyrene) (PCMS) segment in which the chloromethyl groups were converted to 2,2,6,6-tetramethylpiperidinyloxys (TEMPOs) via the amination of PEG-b-PCMS block copolymer with 4-amino-TEMPO. This RNP formed core-shell-type micelles in the physiological environment, and the cumulant average diameter of the RNP was about 50 nm. The cytotoxicity and acute toxicity studies for the RNP revealed that the median inhibitory concentration (IC(50)) of TEMPO radicals in RNP core and median lethal dose (LD(50)) of RNP were >8 mmol N(TEMPO)/L and >600 mg/kg (>960 mumol N(TEMPO)/kg), respectively, indicating fairly low toxicity.

Epidemiology of esophageal cancer: Orient to Occident. Effects of chronology, geography and ethnicity.

Esophageal adenocarcinoma (EAC) has been rapidly increasing in Western countries during the past half century, especially in white men. Esophageal squamous cell carcinoma (ESCC) used to be the dominant type of esophageal malignancy both in Western and Asian countries. The rapid increase of EAC in Western countries has occurred in parallel with an increased prevalence of gastroesophageal reflux disease (GERD) and its major determinant, obesity.

Spheroid array of fetal mouse liver cells constructed on a PEG-gel micropatterned surface: upregulation of hepatic functions by co-culture with nonparenchymal liver cells.

A spheroid array of fetal mouse liver cells, which comprise various immature cells, was constructed on a PEG-gel micropatterned surface and its hepatic activity and degree of differentiation induction were significantly upregulated by co-culture with nonparenchymal liver cells as feeder-cells.

A pH-sensitive fusogenic peptide facilitates endosomal escape and greatly enhances the gene silencing of siRNA-containing nanoparticles in vitro and in vivo.

Previously, we developed a multifunctional envelope-type nano device (MEND) for efficient delivery of both pDNA and siRNA. Modification of a MEND with polyuethylene glycol, i.e.

Enhanced cytoplasmic delivery of siRNA using a stabilized polyion complex based on PEGylated nanogels with a cross-linked polyamine structure.

A novel siRNA delivery system using a polyion complex (PIC) based on PEGylated polyamine nanogels composed of a chemically cross-linked poly[2-(N,N-diethylaminoethyl)methacrylate] (PDEAMA) core and surrounded by PEG tethered chains is described. The nanogel formed PIC spontaneously through electrostatic interaction upon mixing with siRNA. The nanogel/siRNA complex was characterized by a gel retardation assay, size and ζ-potential measurements, and gene silencing activity using a cultured cell line.

Combination therapy with micafungin and amphotericin B for invasive pulmonary aspergillosis in an immunocompromised mouse model.

Objectives: Antifungal monotherapy with polyenes, azoles or echinocandins is not always effective for invasive pulmonary aspergillosis (IPA). The main purpose of this study was to evaluate the efficacy of a combination of micafungin and amphotericin B for the primary treatment of IPA in an immunocompromised mouse model.

Methods: Female ICR mice were used in all experiments.

Efficient short interference RNA delivery to tumor cells using a combination of octaarginine, GALA and tumor-specific, cleavable polyethylene glycol system.

We recently developed a multifunctional envelope-type nano device (MEND) for efficient nucleic acid delivery. Here, we report on the development of an octaarigine (R8)-modified MEND encapsulating small interfering RNA (siRNA) with a tumor-specific, cleavable, polyethylene glycol (PEG)-lipid (PPD). We first determined the optimal concentration of R8 and pH-sensitive fusogenic peptide (GALA) on the lipid envelope of MEND (R8/GALA-MEND).

Regulation of lysozyme activity based on thermotolerant protein/smart polymer complex formation.

Proteins have evolved to acquire highly specialized biological functions and are ideal for various applications in both medicine and biotechnology, although denaturation is one of the major problems in protein chemistry. Here, we show a novel strategy for the regulation and preservation of the enzymatic activity even after heat treatment by the complex formation with a cationic smart copolymer, poly(N,N-diethylaminoethyl methacrylate)-graft-poly(ethylene glycol) (PEAMA-g-PEG). PEAMA-g-PEG suppressed the enzymatic activity of lysozyme completely without any conformational change, indicating complex formation and the capping of the active site of lysozyme by PEAMA-g-PEG.

Inverted pattern formation of cell microarrays on poly(ethylene glycol) (PEG) gel patterned surface and construction of hepatocyte spheroids on unmodified PEG gel microdomains.

We present herein the novel technique for constructing inverted cell-adhesion patternes on PEG gel modified glass surfaces by photoirradiation using the same photomask and materials. The PEG gel micropatterns were prepared by a photolithographic technique using a photomask with 100 microm aligned cavities after spin-coating of a mixed solution of alpha,omega-dimethacryloyl-PEG (PEG-DMA) and a photoinitiator on glass surfaces. When methanol was used as a casting solvent for the spin-coating (Method A), the circular PEG gel domains with a diameter of 100 microm were fabricated on the surface, and as would be predicted, seeded bovine aortic endothelial cells (BAECs) adhered to the glass area on the constructed surface to form a BAECs sheet with 100 microm aligned cavity.

Lipid hydroperoxides in human plasma after ethanol consumption.

Oxidative stress contributes to the pathogenesis of alcoholic liver disease. The purpose of this study is to estimate the amount of oxidative stress that is present when healthy humans consume moderate amounts of ethanol. Blood was collected from healthy volunteers before, 1 h, and 3 h after drinking 400 ml of Japanese rice wine at the rate of 100 ml per 5 min.

Design of core--shell-type nanoparticles carrying stable radicals in the core.

Utilizing the self-assembled core-shell-type polymeric micelle technique, high-performance nanoparticles possessing stable radicals in the core and reactive groups on the periphery were prepared. The anionic ring-opening polymerization of ethylene oxide (EO) was carried out using potassium 3,3-diethoxypropanolate as an initiator, followed by mesylation with methanesulfonyl chloride to obtain acetal-poly(ethylene glycol)-methanesulfonate (acetal-PEG-Ms; 1). Compound 1 was reacted with potassium O-ethyldithiocarbonate, followed by treatment with n-propylamine to obtain heterobifunctional PEG derivatives containing both sulfanyl and acetal terminal groups (acetal-PEG-SH) (2) in a highly selective and quantitative manner.

High-performance immunolatex possessing a mixed-PEG/antibody coimmobilized surface: highly sensitive ferritin immunodiagnostics.

To create a high-performance immunoassay system based on a nanosphere/antibody complex, pentaethylenehexamine-ended poly(ethylene glycol), N6-PEG comprising N6-PEG-5k (M(n) = 6000 g/mol) and N6-PEG-2k (M(n) = 2000 g/mol) was employed as a novel blocking agent to modify the surface of nanospheres. Both the antibody (antiferritin) and the N6-PEG were covalently bonded onto the nanospheres by the linkage of their amino groups with the activated carboxyl groups of those particles. The quantification of antiferritin and tethered N6-PEG polymer was carried out using the copper reduction/bicinchoninic acid reaction (the Micro BCA method).

Binding enhancement of antigen-functionalized PEGylated gold nanoparticles onto antibody-immobilized surface by increasing the functionalized antigen using alpha-sulfanyl-omega-amino-PEG.

We established a technique for constructing PEGylated gold nanoparticles (GNP) that have small compounds with almost complete functionalities on their surfaces using a newly synthesized hetero-telechelic poly(ethylene glycol) (PEG), and their association/dissociation behavior on an antibody-immobilized surface was evaluated using a surface plasmon resonance (SPR) sensor.

An autopsy case of poisoning with ethanol and psychotropic drugs.

A case of fatal poisoning involving ethanol with psychotropic drugs is presented. Quantitative toxicological analysis showed that the concentrations of ethanol, amoxapine and phenobarbital in the femoral blood were 2.86 mg/ml, 0.

Facile construction of sulfanyl-terminated poly(ethylene glycol)-brushed layer on a gold surface for protein immobilization by the combined use of sulfanyl-ended telechelic and semitelechelic poly(ethylene glycol)s.

A sulfanyl-terminated poly(ethylene glycol) (PEG)-brushed layer was constructed on a gold sensor platform by consecutive treatment with a sulfanyl-ended semitelechelic PEG (2 kDa, hereafter "MeO-PEG-SH (2k)") and a sulfanyl-ended telechelic PEG (5 kDa, hereafter "SH-PEG-SH (5k)"). Our strategy of constructing the sulfanyl-terminated PEG-brushed gold surface is based on mixed-PEG-brush formation from the longer SH-PEG-SH (5k) and the shorter MeO-PEG-SH (2k), where the preimmobilized shorter MeO-PEG-SH (2k) prevents loop formation in the longer SH-PEG-SH (5k) on the surface and the free sulfanyl group at one end of the longer SH-PEG-SH is exposed to the mixed-PEG tethered-chain surface. From the experimental results obtained from surface plasmon resonance analysis, it became apparent that the immobilization density and the orientation of the longer SH-PEG-SH (5k) on the gold surface could be controlled by the amount of preimmobilized shorter MeO-PEG-SH (2k).

Design of poly(ethylene glycol)/streptavidin coimmobilized upconversion nanophosphors and their application to fluorescence biolabeling.

Infrared-to-visible upconversion phosphors (i.e., rare earth ion-doped Y2O3 nanoparticles (UNPs)) were synthesized by the homogeneous precipitation method.

Antimicrobial susceptibility and molecular epidemiological analysis of clinical strains of Pseudomonas aeruginosa.

Three hundred and seventy-one strains of Pseudomonas aeruginosa were isolated at the laboratory of Kyushu University Hospital in Japan from May 2002 through January 2003. Large proportions of isolated strains were resistant to carbapenems: 37.5% to imipenem, 21.

Structure and activity assay of nanozymes prepared by the coimmobilization of practically useful enzymes and hydrophilic block copolymers on gold nanoparticles.

Enzyme/polymer/gold nanoparticle hybrids, called "nanozymes", were prepared and structurally analyzed by dynamic light scattering (DLS), ultraviolet-visible spectroscopy, and zeta-potential and transmission electron microscopy (TEM) measurements, which showed that the nanozyme particles were mainly composed of a single gold nanoparticle, on whose surface the enzyme and polymer were coimmobilized. This kind of structure resulted in the high dispersion stability of the nanozyme under various conditions, accompanied by improved thermal stability of the enzyme.