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The α-galactosyl epitope is a terminal N-glycan moiety of glycoproteins found in mammals except in humans, and thus, it is recognized as an antigen that provokes an immunogenic response in humans. Accordingly, it is necessary to analyze the α-galactosyl structure in biopharmaceuticals or organ transplants. Due to an identical glycan composition and molecular mass between α-galactosyl N-glycans and hybrid/high-mannose-type N-glycans, it is challenging to characterize α-galactosyl epitopes in N-glycoproteins using mass spectrometry. Here, we describe a method to identify α-galactosyl N-glycopeptides in mice glycoproteins using liquid chromatography with tandem mass spectrometry with higher-energy collisional dissociation (HCD). The first measure was an absence of [YHM] ion peaks in the HCD spectra, which was exclusively observed in hybrid and/or high-mannose-type N-glycopeptides. The second complementary criterion was the ratio of an m/z528.19 (Hex2HexNAc1) ion to m/z366.14 (Hex1HexNAc1) ion (Im/z528/Im/z366). The measure of [Im/z528/Im/z366> 0.3] enabled a clear-cut determination of α-galactosyl N-glycopeptides with high accuracy. In Ggta1 knockout mice, we could not find any α-galactosyl N-glycoproteins identified in WT mice plasma. Using this method, we could screen for α-galactosyl N-glycoproteins from mice spleen, lungs, and plasma samples in a highly sensitive and specific manner. Conclusively, we suggest that this method will provide a robust analytical tool for determination of α-galactosyl epitopes in pharmaceuticals and complex biological samples.

A great deal of effort has been expended to develop accurate means of determining the properties of synthetic polymers using matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS). Many studies have focused on the importance of sample pre-treatment to obtain accurate analysis results. This review discusses the history of synthetic polymer characterization and highlights several applications of MALDI-TOF MS that recognize the importance of pre-treatment technologies. The subject area is of significance in the field of analytical chemistry, especially for users of the MALDI technique. Since the 2000s, many such technologies have been developed that feature improved methods and conditions, including solvent-free systems. In addition, the recent diversification of matrix types and the development of carbon-based matrix materials are described herein together with the current status and future directions of MALDI-TOF MS hardware and software development. We provide a summary of processes used for obtaining the best analytical results with synthetic polymeric materials using MALDI-TOF MS.

Sarcopenia, characterized by reduced muscle mass and fiber number leading to muscular atrophy, has been associated with serious socioeconomic challenges among the elderly in developed countries. Therefore, preventing sarcopenia could be a promising strategy for achieving a healthy aging society. Nutmeg (Myristica fragrans) has been used as a spice to increase flavor and prevent putrefaction of food. Nutmeg contains various bioactive components that improve muscle activity. To determine the potential effect of lignan-enriched nutmeg extract (LNX) on sarcopenia, LNX (100 mg/kg body weight)-fed aged mice were subjected to forced exercise. Herein, aged (22-month-old) mice fed LNX for three weeks exhibited a shortened and thickened soleus muscle. The ratio of the soleus muscle mass (%) to body weight was significantly increased in LNX-fed aged mice. The relative increase in muscle mass in LNX-fed aged mice improved exercise activities, including rotarod, swimming, and grip strength test results. Proteome profiles of the soleus muscle of LNX-fed mice were used to analyze protein–protein interaction network. Several myosin heavy chain isoforms were found to interact with actin, ACTA1, which functions as a hub protein. Furthermore, the expression of myogenic proteins, such as MYH1, MYH4, and ACTA1, was dose-dependently increased in vivo. In result, our functional proteomic analysis revealed that feeding LNX restored muscle proteins in aged mice.

This paper describes a simple electrochemical sensing platform based on single-walled carbon nanotube (SWCNT) electrodes for glucose detection. The device fabrication using O2-plasma treatment allows precision and uniformity for the construction of three SWCNT electrodes on the flexible plastic substrate. Glucose assay can be simply accomplished by introducing a glucose sample into the fabricated biosensor. The marked electrocatalytic and biocompatible properties of biosensors based on SWCNT electrodes with the incorporation of ferrocenecarboxylic acid and polyethylene glycol enable effective amperometric measurement of glucose at a low oxidation potential (0.3 V) with low interferences from coexisting species. The device shows efficient electroanalytical performances with high sensitivity (5.5 μA·mM−1·cm−2), good reproducibility (CV less than 3%), and long-term stability (over a month). A linear range of response was found from 0 to 10 mM of glucose with a fast response time of 10 s. This attractive electroanalytical device based on GOx/FCA/PEG/SWCNT electrodes offers a promising system to facilitate a new approach for diverse biosensors and electrochemical devices.

Extracellular matrix (ECM) proteins play a pivotal role in cell growth and differentiation. To characterize aged ECM proteins, we compared the proteomes by shotgun method of young (passage #15) and late senescent (passage #40) human dermal fibroblasts (HDFs) using SDS-PAGE coupled with LC–MS/MS. The relative abundance of identified proteins was determined using mol% of individual proteins as a semi-quantitative index. Fifteen ECM proteins including apolipoprotein B (APOB) and high-temperature requirement factor 1 (HTRA1) were up-regulated, whereas 50 proteins including fibronectin 1 (FN1) and vitronectin (VTN) were down-regulated in late senescent HDFs. The identified ECM proteins combined with plasma membrane were queried to construct the protein–protein interaction network using Ingenuity Pathways Analysis, resulting in a distinct FN1-centered network. Of differentially abundant ECM proteins in shotgun proteomics, the protein levels of FN1, VTN, APOB, and HTRA1 were verified by immunoblot analysis. The results suggest that the aging process in HDFs might be finally involved in the impaired FN1 regulatory ECM network combined with altered interaction of neighboring proteins. Shotgun proteomics of highly aged HDFs provides insight for further studies of late senescence-related alterations in ECM proteins.

Objective.Pulmonary involvement is common in patients with systemic sclerosis (SSc), and this condition causes substantial morbidity and mortality. Disrupted immunity from the disease or associated medication may render such patients subject to tuberculosis (TB) infection. However, the relationship between SSc and TB has not yet been investigated.Methods.Using the Taiwan National Health Insurance Research Database, 838 patients with SSc diagnosed in Taiwan during 2000–2006 were identified and followed for emergence of TB infection. Incidence rate ratios (IRR) of TB compared to 8380 randomly selected age-, sex-, and comorbidity-matched controls without SSc were calculated. The Cox proportional hazards model was used for multivariate adjustment to identify independent risk factors for TB infection.Results.The risk of TB infection was higher in the SSc cohort than in controls (IRR 2.81, 95% CI 1.36–5.37; p = 0.004), particularly for pulmonary TB (IRR 2.53, 95% CI 1.08–5.30; p = 0.022). Other independent risk factors for TB infection in patients with SSc were age ≥ 60 years [hazard ratio (HR) 3.52, 95% CI 1.10–11.33; p = 0.035] and pulmonary hypertension (PH; HR 6.06, 95% CI 1.59–23.17; p = 0.008). Mortality did not differ for SSc patients with or without TB.Conclusion.In this nationwide study, the incidence of TB infection was significantly higher among patients with SSc than in controls without SSc. Special care should be taken in managing patients with SSc who are at high risk for TB, especially those aged ≥ 60 years or who also have PH.

This research applied a stylus probe without balance and lever arm as in the previous design of a contact-force-controlled Scanning Probe Microscope (SPM) system. The controller integrated both Ziegler-Nichols-based and intelligent fuzzy methods; thus the systems relative stability can be reserved under the nominal conditions. In addition, one can see that both hysteresis and parameter variation effects of the force actuator can be reduced. Comparing the results with the traditional Ziegler-Nichols-based controller by simulation, one can see that the proposed systems are much more robust.

AbstractIn the present study, a high-quality voxel model of a Korean adult male was converted to a surface model based on polygon and nonuniform rational B-spline surfaces. The polygon model of the body surface was then modified in the back and buttock regions for some correction and finally converted back to a voxel model for Monte Carlo dose calculations. The dose calculation results showed that the modification of the back and buttock significantly changed the calculated dose values of the lungs and breasts for the postero-anterior irradiation geometry; the maximum difference, found for the lungs, was as large as 40% for the photon energy of 30 keV, even though the difference decreases with the photon energy.

The objective of this study was to adjust the height, weight, and organ and tissue sizes of a Korean voxel model in order to construct a Reference Korean voxel model. The adjustment of the height and skeletal mass was achieved by scaling the voxel dimensions. The sizes of the organs and tissues were adjusted to the Reference Korean data by adding or removing voxels on the surface. The adjusted voxel model is 171 cm in height, 68 kg in weight, which exactly matches the Reference Korean data. The size of the voxels (= voxel resolution) is 1.981 mm × 1.981 mm × 2.0854 mm. The organ and tissue masses of the adjusted model also are in a good agreement with the Reference Korean data; the differences are less than 7% for most of the organs and tissues. The unadjusted and adjusted voxel models were ported to the MCNPX Monte Carlo particle transport simulation code to calculate the equivalent doses to the organs and tissues and the effective doses. The calculated values were then compared in order to quantify the effect of the adjustment.

In this study, a high-quality voxel model of a Korean adult male was constructed using the Visible Korean Human (VKH) project’s serially sectioned anatomical images. The VKH images are transverse color photographs obtained from the serial sectioning of an adult Korean male cadaver (164 cm, 55 kg) at 0.2 mm intervals. A total of 28 organs and tissues were segmented with the color photographic images. The height and weight of the constructed voxel model, VKH-Man, is 164 cm and 59.6 kg, respectively. The voxel resolution of the model is 1.875 mm × 1.875 mm × 2 mm. The developed model was implemented into a Monte Carlo particle transport simulation code, MCNPX, to calculate the organ and tissue doses and, thereby, the effective doses, and the calculated values were compared with the values obtained from other computational models (KTMAN-2, VIP-Man, and ICRP-74).

Nanoporous SiC membrane was developed on the porous alumina plate for the hydrogen separation using preceramic polymers such as polyphenylcarbosilane. The prepared preceramic polymers were characterized with FT-IR, TGA, GPC and XRD. Nanoporous SiC membrane was derived from the preceramic polymer using a spin coating method. The SiC membrane spin coated using 20 wt.% of polyphenylcarbosilane solution in cyclohexane does not show any cracks on the surface after heat treatment at 800oC. The average thickness of the SiC membrane is about 1µm. SiC coated porous alumina possesses asymmetric pore size distribution. There are micropores that originated from porous alumina substrate, and nanopores that derived from amorphous state of SiC membranes. The pore size distribution measurement showed that the sample contains 1-3 nm sized nano pores.

The structural determination of sn‐1 and sn‐2 hexadecanoic lysophosphatidylcholine (LPC) regioisomers was carried out using fast atom bombardment tandem mass spectrometry (FAB‐MS/MS). The collision‐induced dissociation (CID) of protonated and sodiated molecules produced diverse product ions due mainly to charge remote fragmentations. Based on the information obtained from the CID spectra of protonated and sodiated molecules, sn‐1and sn‐2hexadecanoic LPC isomers could be discriminated. Especially, the abundance ratio of the diagnostic ion pair [m/z224/226] in the CID spectra of [M + H]+ions was shown to be greatly different. Moreover, the CID‐MS/MS spectra of sodium‐adducted molecules for hexadecanoic LPC isomers showed characteristic product ions such as [M + Na − 103]+, [M + Na − 85]+, and [M + Na − 59]+, by which their regio‐specificity can be differentiated. Copyright © 2002 John Wiley & Sons, Ltd.

A series of lysophosphatidylcholines were isolated from the marine sponge Spirastrella abata by reversed-phase high performance liquid chromatography (HPLC) and analyzed by fast atom bombardment mass spectrometry (FAB-MS). Their structural elucidation was carried out with fast atom bombardment tandem mass spectrometry (FAB-MS/MS). The collision-induced dissociation (CID) of protonated and sodiated molecular ions produced diverse product ions via a series of dissociative processes. Because of the positive charge of the amine group at the end of the molecules, charge-remote fragmentation patterns of specific ions, [M + H]⁺ or [M + Na]⁺, were very helpful for the identification of product ions which are characteristic for choline and long hydrocarbon chains substituted at the glycerol back bone. Moreover, the CID-MS/MS spectra of sodium adducted molecular ions for lysophosphatidylcholines yielded common characteristic fragment ions for the choline moiety and characteristic ions [M + Na-103]⁺, [M + Na-85]⁺ and [M + Na-59]⁺ in the higher mass region. Copyright © 2001 John Wiley & Sons, Ltd.

The article shares the author's views on the need for Korea to increase foreign aid to gain international respect. The author cites that the foreign aid of the country is not enough considering that its economic power is ranked 12th in the world. He asserts that an increase in foreign aid is important for Korean industries to embark into foreign markets. He adds that the country should raise the amount on credit basis through the Economic Development Cooperation Fund and other channels.

An optical pickup has been developed for both digital versatile discs (DVD) and compact discs (CD) using an annular mask on an objective lens. A conventional lens without the annular mask has been optimized only for DVD disc with 0.6 mm-thickness. The intensity of the secondary peaks of the spot focused by the objective lens with an annular mask to a CD is reduced and the pickup is found to have large tolerance for disc tilt variation compared with a conventional objective lens without an annular mask.

A compact and inexpensive design for a laser disc(LD)-compatible digital versatile disc(DVD) pickup that uses a special annular lens is presented and the measurement technique of the lens is described. One objective lens having a special annular area functions as an aberration-corrected lens for reading LD, compact disc recordable(CDR) and DVD regardless of differences in substrate thickness. The special area has an aspherical surface optimized for a thick substrate. This lens can also be used for compact disc rewritable(CDRW).