Electrochemical impedimetric biosensor based on a nanostructured polycarbonate substrate

This study integrates the techniques of nanoelectroforming, hot-embossing, and electrochemical deposition to develop a disposable, low-cost, and high sensitivity nanostructure biosensor. A modified anodic aluminum oxide barrier-layer surface was used as the template for thin nickel film deposition. After etching the anodic aluminum oxide template off, a three-dimensional mold of the concave nanostructure array was created. The fabricated three-dimensional nickel mold was further used for replica molding of a nanostructure polycarbonate substrate by hot-embossing. A thin gold film was then sputtered onto the polycarbonate substrate to form the electrode, followed by deposition of an orderly and uniform gold nanoparticle layer on the three-dimensional gold electrode using electrochemical deposition. Finally, silver nanoparticles were deposited on the uniformly deposited gold nanoparticles to enhance the conductivity of the sensor. Electrochemical impedance spectroscopy analysis was then used to detect the concentration of the target element. The sensitivity of the proposed scheme on the detection of the dust mite antigen, Der p2, reached 0.1 pg/mL

Alterations in IL-6, IL-8, GM-CSF. TNF-α, and IFN-γ Release by Peripheral Mononuclear Cells in Patients with Active Vitiligo

The purpose of this study was to clarify the relationship between the cellular and humoral immune components in the pathogenesis of vitiligo vulgaris. By using cytokines as indicators of peripheral mononuclear cell (MNC) function, we compared the effects of phytohemagglutinin (PHA) and purified IgG on MNCs derived from patients suffering from active vitiligo with those from normal controls. The results revealed (i) a significant increase in spontaneous production of 11-6 and IL-8 in patients; (ii) PHA, purified IgG from patients (IgG-anti-MC), or IgG from normal controls (N-IgG) induced a significant increase in IL-6 but diminished GM-CSF, TNF-α, and IFN-γ release in patients; and (iii) IgG-anti-MC brought about a significantly higher stimulatory effect on IL-1β and IFN-γ production than N-IgG in normal controls. Immunologically, IL-6 can enhance melanocyte ICAM-1 expression, which may increase leukocyte-melanocyte attachment and cause melanocyte damage in vitiligo. A decrease in GM-CSF (an intrinsic growth factor for melanocyte) production may retard recovery from vitiligo by checking the proliferation of surviving melanocytes. A significant decrease in TNF-α and IFN-γ production may partially explain the reduced inflammatory reaction in vitiliginous lesions. That IgG-anti-MC stimulates an increase in IL-1β and IFN-γ production in controls suggests that IgG-anti-MC may play a role in melanocyte destruction mediated by monocytes

Liquid-Crystal-Based Phase Gratings and Beam Steerers for Terahertz Waves

We review our theoretical and experimental studies on a class of liquid crystal (LC) photonic devices, i.e., terahertz (THz) phase gratings and beam steerers by using LCs. Such gratings can function as a THz polarizer and tunable THz beam splitters. The beam splitting ratio of the zeroth-order diffraction to the first-order diffraction by the grating can be tuned from 10:1 to 3:5. Gratings with two different base dimensions were prepared. The insertion loss is lower by approximately 2.5 dB for the one with the smaller base. The response times of the gratings were also studied and were long (tens of seconds) as expected because of the thick LC layer used. Accordingly, the devices are not suitable for applications that require fast modulation. However, they are suitable for instrumentation or apparatuses that require precise control, e.g., an apparatus requiring a fixed beam splitting ratio with occasional fine tuning. Schemes for speeding up the device responses were proposed. Based on the grating structure, we also achieved an electrically tunable THz beam steerer. Broadband THz radiation can be steered by 8.5° with respect to the incident beam by varying the driving voltages to yield the designed phase gradient

Staphylococcal Cassette Chromosome mec in MRSA, Taiwan

To determine the predominant staphylococcal cassette chromosome (SCC) mec element in methicillin-resistant Staphylococcus aureus, we typed 190 isolates from a hospital in Taiwan. We found a shift from type IV to type III SCCmec element during 1992–2003, perhaps caused by selective pressure from indiscriminate use of antimicrobial drugs

Growth mechanism and magnon excitation in NiO nanowalls

The nanosized effects of short-range multimagnon excitation behavior and short-circuit diffusion in NiO nanowalls synthesized using the Ni grid thermal treatment method were observed. The energy dispersive spectroscopy mapping technique was used to characterize the growth mechanism, and confocal Raman scattering was used to probe the antiferromagnetic exchange energy J2 between next-nearest-neighboring Ni ions in NiO nanowalls at various growth temperatures below the Neel temperature. This study shows that short spin correlation leads to an exponential dependence of the growth temperatures and the existence of nickel vacancies during the magnon excitation. Four-magnon configurations were determined from the scattering factor, revealing a lowest state and monotonic change with the growth temperature

Obestatin stimulates glucose-induced insulin secretion through ghrelin receptor GHS-R

AbstractOrexigenic hormone ghrelin and anorexic hormone obestatin are encoded by the same preproghrelin gene. While it is known that ghrelin inhibits glucose-stimulated insulin secretion (GSIS), the effect of obestatin on GSIS is unclear. Ghrelin’s effect is mediated by its receptor Growth Hormone Secretagogue Receptor (GHS-R), but the physiologically relevant receptor of obestatin remains debatable. Here we have investigated the effect of obestatin on GSIS in vitro, in vivo and ex vivo, and tested whether obestatin regulates insulin secretion through GHS-R. We found that under hyperglycemic condition, obestatin augments GSIS in rat insulinoma cells (INS-1) and in pancreatic islets from ghrelin−/− mice. Surprisingly, obestatin-induced GSIS was absent in β-cells in which GHS-R was suppressed. Obestatin-induced insulin secretion was abolished in the circulation of Ghsr−/− mice, and in pancreatic islets isolated from Ghsr−/− mice. We also found that obestatin-induced GSIS was attenuated in islets isolated from β-cell-specific Ghsr knockout MIP-Cre/ERT;Ghsrf/f mice. Our data collectively demonstrate that obestatin is a potent insulin secretagogue under hyperglycemic condition, and obestatin’s effect on insulin secretion is mediated by GHS-R in pancreatic β-cells. Our findings reveal an intriguing insight that obestatin and ghrelin have opposing effects on insulin secretion, and both are mediated through ghrelin receptor GHS-R.</jats:p

Improving Detection Accuracy of Lung Cancer Serum Proteomic Profiling via Two-Stage Training Process

<p>Abstract</p> <p>Background</p> <p>Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS) is a frequently used technique for cancer biomarker research. The specificity of biomarkers detected by SELDI can be influenced by concomitant inflammation. This study aimed to increase detection accuracy using a two-stage analysis process.</p> <p>Methods</p> <p>Sera from 118 lung cancer patients, 72 healthy individuals, and 31 patients with inflammatory disease were randomly divided into training and testing groups by 3:2 ratio. In the training group, the traditional method of using SELDI profile analysis to directly distinguish lung cancer patients from sera was used. The two-stage analysis of distinguishing the healthy people and non-healthy patients (1^st-stage) and then differentiating cancer patients from inflammatory disease patients (2^nd-stage) to minimize the influence of inflammation was validated in the test group.</p> <p>Results</p> <p>In the test group, the one-stage method had 87.2% sensitivity, 37.5% specificity, and 64.4% accuracy. The two-stage method had lower sensitivity (> 70.1%) but statistically higher specificity (80%) and accuracy (74.7%). The predominantly expressed protein peak at 11480 Da was the primary splitter regardless of one- or two-stage analysis. This peak was suspected to be SAA (Serum Amyloid A) due to the similar m/z countered around this area. This hypothesis was further tested using an SAA ELISA assay.</p> <p>Conclusions</p> <p>Inflammatory disease can severely interfere with the detection accuracy of SELDI profiles for lung cancer. Using a two-stage training process will improve the specificity and accuracy of detecting lung cancer.</p

A new era for studies on cross-Strait relations: introduction

After more than half a century’s separation, interaction between China and Taiwan has increased and has progressively changed from a politico-economic interaction to a more civic interaction. Scholars working on cross-Strait relations have recently begun to pay attention to the civic influence of Taiwanese businesses on the relationship. Some emphasize the importance of sub-governmental interactions in the process of cross-Strait integration. Others assert that Taiwanese businesses can exercise economic leverage to constrain the Chinese government in cross-Strait policymaking. These scholars stress bottom–up processes by observing current phenomena, then deducing the emerging pattern of cross-Strait relations that may be influenced by business activities. Taking account of changing trends in scholarly discussions of the cross-Strait relationship, this special issue of China Information presents current research in this field. Unlike studies on top–down processes that affect political and economic interactions between China and Taiwan, several contributions in the special issue highlight bottom–up mechanisms affecting such interactions by examining the identity of Taiwanese businesspeople and migrants, as well as the activities and implications of Taiwanese charitable organizations operating in China. This issue focuses not only on the impact of China on Taiwan, but also the impact of Taiwanese investments, migrants, and exports on Chinese society