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Background Pancreatic cancer (PC) has a grim prognosis, and an early diagnostic biomarker has been highly desired. The molecular link between diabetes and PC has not been well established. Methods Bioinformatics screening was performed for a serum PC marker. Experiments in cell lines (5 PC and 1 normal cell lines), mouse models, and human tissue staining (37 PC and 10 normal cases) were performed to test asprosin production from PC. Asprosin’s diagnostic performance was tested with serums from multi-center cohorts (347 PC, 209 normal, and 55 additional diabetic patients) and evaluated according to PC status, stages, and diabetic status, which was compared with that of CA19-9. Results Asprosin, a diabetes-related hormone, was found from the bioinformatics screening, and its production from PC was confirmed. Serum asprosin levels from multi-center cohorts yielded an age-adjusted diagnostic area under the curve (AUC) of 0.987 (95% confidence interval [CI] = 0.961 to 0.997), superior to that of CA19-9 (AUC = 0.876, 95% CI = 0.847 to 0.905), and a cut-off of 7.18 ng/mL, at which the validation set exhibited a sensitivity of 0.957 and a specificity of 0.924. Importantly, the performance was maintained in early-stage and non-metastatic PC, consistent with the tissue staining. A slightly lower performance against additional diabetic patients (n = 55) was restored by combining asprosin and CA19-9 (AUC = 0.985, 95% CI = 0.975 to 0.995). Conclusions Asprosin is presented as an early-stage PC serum marker that may provide clues for PC-induced diabetes. Larger prospective clinical studies are warranted to solidify its utility.

Isocitrate dehydrogenase (IDH) mutations are found in low-grade gliomas, and the product of the IDH mutant (MT), 2-hydroxyglutarate (2-HG), is the first known oncometabolite. However, the roles of the IDH wild type (WT) in high-grade glioblastoma, which rarely has the IDH mutation, are still unknown. To investigate possible pathways related to IDH WT in gliomas, we carried out bioinformatics analysis, and found that IDH1 has several putative calmodulin (CaM) binding sites. Pull-down and quantitative dissociation constant (Kd) measurements using recombinant proteins showed that IDH1 WT indeed binds to CaM with a higher affinity than IDH1 R132H MT. This biochemical interaction was demonstrated also in the cellular environment by immunoprecipitation with glioblastoma cell extracts. A synthetic peptide for the suggested binding region interfered with the interaction between CaM and IDH1, confirming the specificity of the binding. Direct binding between the synthetic peptide and CaM was observed in an NMR binding experiment, which additionally revealed that the peptide initially binds to the C-lobe of CaM. The physiological meaning of the CaM-IDH1 WT binding was shown with trifluoperazine (TFP), a CaM antagonist, which disrupted the binding and inhibited survival and migration of glioblastoma cells with IDH1 WT. As CaM signaling is activated in glioblastoma, our results suggest that IDH1 WT may be involved in the CaM-signaling pathway in the tumorigenesis of high-grade gliomas. (C) 2020 Elsevier Inc. All rights reserved.

Objective—To evaluate the effects of peribulbar anesthesia (sub-Tenon injection of lidocaine hydrochloride) on akinesia of extraocular muscles, mydriasis, and intraoperative and postoperative analgesia in dogs undergoing phacoemulsification. Animals—14 Beagles with ophthalmically normal eyes. Procedures—A blinded randomized controlled trial was performed. Dogs were anesthetized and assigned to 2 treatments: concurrent sub-Tenon injection of 2% lidocaine hydrochloride solution (2 mL) and IV injection of saline (0.9% NaCl) solution (0.02 mL/kg; lidocaine group [n = 7]) or concurrent sub-Tenon injection of saline solution (2 mL) and IV injection of 0.2 mg of atracurium/kg (0.02 mL/kg; control group [7]). Pupils were dilated by topical application of a combined tropicamide and phenylephrine ophthalmic solution. Ten minutes after the injections, pupil diameter was measured and phacoemulsification was performed. End-tidal isoflurane concentration was used to evaluate intraoperative pain. Subjective pain scores were recorded during the postoperative period. Results—Akinesia was induced and maintained throughout the surgery in all eyes. Mean ± SD pupil diameter was significantly greater in the lidocaine group (13.7 ± 0.7 mm) than in the control group (12.2 ± 0.8 mm). Isoflurane requirements were significantly lower in the lidocaine group than the control group. However, postoperative pain scores were not significantly different between the groups. Conclusions and Clinical Relevance—Sub-Tenon injection of lidocaine was an effective method for inducing akinesia of extraocular muscles, mydriasis, and intraoperative analgesia for phacoemulsification in dogs. Therefore, this could be another option for surgical field exposure and pain management during phacoemulsification in dogs.

FKBP12, an FK506 binding protein, interacts with type 1 ryanodine receptor (RyR1) and modulates its calcium channel activity. However, there are many opposing reports of FKBP12’s interaction with other related calcium channels, such as type 1 IP3 receptor and type 3 ryanodine receptor (IP3R1 and RyR3). In addition, the involvement of the prolyl-dipeptide motif in the calcium channels and the corresponding binding residues in FKBP12 remain controversial. Through pulldown assays with recombinant proteins, we provide biochemical evidence of the interaction between FKBP12 and RyR1, RyR3 and IP3R1. Using NMR chemical shift mapping, we show that the important binding residues in FKBP12 are located in its hydrophobic FK506 binding region. Consistently, we demonstrate that FK506 can competitively inhibit the interaction between FKBP12 and the dipeptide motifs of the calcium channels. We believe our results shed lights on the binding mechanism of calcium channel–FKBP12 interaction.

Our goal was to develop a topology-insensitive rivet bonding method using the sidewall bond principle for MEMS devices and evaluate its mechanical characteristics. The proposed bonding method is comprised of two fundamental structures with a sidewall bond between them. The first is a male wafer having a relatively thick solder as a donor, and the second is a female wafer as an acceptor with a structure similar to a through-via. The two wafers are bonded laterally by the reflow phenomena of the solder and the excess volume of the donor with the acceptor then generating a rivet. In this study, these structural features were investigated. The rivet bonding led to an enhancement in the bonding strength due to the plastic hardening behavior of the rivet, serving as a cushion for the stress. This was parametrically studied and experimentally verified. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Cisplatin has been one of the most widely used anticancer agents, but its nephrotoxicity remains a dose-limiting complication. Here, we evaluated the idiopathic nature and the predose prediction of cisplatin-induced nephrotoxicity using a nuclear magnetic resonance (NMR)-based pharmacometabonomic approach. Cisplatin produced serious toxic responses in some animals (toxic group), but had little effect in others (nontoxic group), as judged by hematological and histological results. The individual metabolic profiles, assessed by urine NMR spectra, showed large differences between the post-administration profiles of the two groups, indicating the relevance of the NMR approach. Importantly, multivariate analysis of the NMR data showed that the toxic and nontoxic groups can be differentiated based on the pretreatment metabolite profiles. Leave-one-out analysis, performed to evaluate the practical performance of our approach, gave a 66% accuracy rate in predicting toxic responses based on the pretreatment metabolite profiles. Hence, we provide a working model that can explain the idiopathic toxicity mechanism based on marker metabolites found by NMR analysis consistent with tissue NADH measurements. Thus, a pharmacometabonomic approach using pretreatment metabolite profiles may help expedite personalized chemotherapy of anticancer drugs.

The roles of calmodulin (CaM) have been key points of controversy in the regulation of inositol-1,4,5-trisphosphate receptor (IP(3)R). To address the issue, we studied the interaction between CaM and the suppressor domain of IP(3)R, a key allosteric regulatory domain. First, by means of a pulldown and a fluorescence titration experiment, we confirmed the interaction. Through subsequent NMR binding experiments, we observed dramatic peak disappearances of the suppressor domain on interaction with apo-CaM. The data indicated that apo-CaM induces large-scale dynamic conformational changes in the suppressor domain, involving partial unfolding and subdomain rearrangement. Analysis of the NMR data of CaM surprisingly revealed that its C lobe alone can cause such changes. Further binding experiments showed that calcium allows the free N lobe to bind to the suppressor domain, which induces extra conformational changes in both of the proteins. These results were also confirmed with CaM deletion mutants with either the N or C lobe. On the basis of this novel binding mechanism, we propose a model in which the partial unfolding of the suppressor domain by apo-CaM and the stepwise binding of the N lobe of CaM to the suppressor domain are important elements of calcium/CaM inhibition of IP(3)R. We believe that our working model encompasses previous regulation mechanisms of IP(3)R by calcium/CaM and provides new insights into the CaM-target interaction.

Deer antler has been widely used as a dietary supplement for hundreds of years in Asian countries. The chemical composition of deer antlers strongly depends on the growth conditions of the deer, especially the feeds, but the effects of different feeds on deer antlers have not been studied. To expand our knowledge of the chemical constituents of deer antler and establish an efficient way of differentiating antlers obtained with different feeds, we applied an NMR-based metabolomics approach and OPLS-DA multivariate analysis. We show that the antlers from one species on two different feeds, made from grass or mulberry trees, can be reliably differentiated by our metabolomics approach. We identified chemical constituents of the deer antlers and the marker compounds that contribute to the difference between the feed groups. We also rigorously validated our differentiation approach by showing that it can correctly classify blind samples into their respective feed groups. Our approach is expected to help design feeds to produce antlers with more defined constituents, especially those with higher bioactivities.

Background & Aims Biliary tract cancer is highly lethal at presentation, with increasing mortality worldwide. Current diagnostic measures employing multiple criteria such as imaging, cytology, and serum tumor markers are not satisfactory, and a new diagnostic tool is needed. Because bile is a cognate metabolite-rich bio-fluid in the biliary ductal system, we tested a new metabolomic approach to develop an effective diagnostic tool. Methods Biles were collected prospectively from patients with cancer ( n =17) or benign biliary tract diseases ( n =21) with percutaneous or endoscopic methods. Nuclear magnetic resonance spectra (NMR) of these biles were analyzed using orthogonal partial least square discriminant analysis (OPLS-DA). Results The metabolomic 2-D score plot showed good separation between cancer and benign groups. The contributing NMR signals were analyzed using a statistical TOCSY approach. The diagnostic performance assessed by leave-one-out analysis exhibited 88% sensitivity and 81% specificity, better than the conventional markers (CEA, CA19-9, and bile cytology). Conclusion The NMR-based metabolomics approach provides good performance in discriminating cancer and benign biliary duct diseases. The excellent predictability of the method suggests that it can, at least, augment the currently available diagnostic approaches.

Introduction – Ganoderma lucidum is a widely used and high-value medicinal natural product. Correct identification of its cultivation source is important for proper quality assurance, but is so far mostly dependent on subjective morphological examinations. Objective – To develop an efficient way of discriminating the cultivation sources of Ganoderma lucidum, particularly those from Korea and China, the two major sources of the mushroom using NMR-based metabolomic differentiation. Methodology – Ganoderma lucidum samples were collected from Korea (26 samples) and China (20 samples), and their NMR spectra were obtained. The raw data were processed, and analysed using multivariate statistical analysis. Results – Although conventional principal component analysis showed some overlaps, orthogonal projections to latent structure discriminant analysis (OPLS-DA) provided clean distinction between samples from the two countries. Contributing signals were also identified using S-plot, and further verified with independent t-test. Final validation of the model was obtained using prediction test of the unknowns, where the model predicted all of the 14 test samples correctly. Distinction between the cultivation sources within China was also established. Conclusion – The easiness and transferability of our NMR-based approach should contribute to addressing an important aspect of quality control process of Ganoderma lucidum. We believe the method can be easily applied to other herbal medical products. Copyright © 2009 John Wiley & Sons, Ltd.

Microstructural analyses were undertaken of Ti(CN)-based partially-complete solid-solution cermets (PSS). They are prepared from Ti(CN)-based carbide cermet (TCC) blended with the (Ti,W)C complete solid-solution phase (CSS) in order to evaluate the effect of the CSS on TCC. All of the systems analyzed in this study show a typical core-rim structure. The proportion of CSS content was varied from 5 to 50 wt.%. A large CSS content induced the formation of coreless solid-solution phases and remarkable changes in the microstructure of the PSS cermets in contrast to the initial TCC. Increasing CSS content led to a decrease in the total area fraction of Ti(CN) cores of the TCC and the growth of the rim. The toughness of the PSS was improved greatly with the addition of CSS. The obtained results indicate that the addition of CSS enables the control of the microstructure and mechanical properties of carbide cermets.

Aspirin or acetylsalicylic acid, a member of the salicylate family, is frequently used as an analgesic, antipyretic, anti-inflammatory and antiplatelet drug. Because aspirin is chemically unstable in water and heat for tablet formulation, additives including lubricants are used in preparing aspirin tablets, using a dry-granulation process. Aspirin tablets are produced by a number of manufacturers which usually use their own unique combination of additives during the manufacturing process. In this study, we employed an NMR based metabolomics technique to identify the manufacturers of various aspirin tablets. Aspirin tablets from six different companies were analyzed by 1H 400 MHz NMR. The acquired data was then integrated and processed by principal component analysis (PCA). Based on the NMR data, we were able to identify peaks corresponding to acetylsalicylic acid in all of the six samples, whereas different NMR patterns were found in the aromatic and aliphatic regions depending on the unique additive used. These observations led to the conclusion that the differences in the NMR patterns among the different aspirin tablets were due to the presence of additives.

Correct identification of the origins of herbal medical products is becoming increasingly important in tandem with the growing interest in alternative medicine. However, visual inspection of raw material is still the most widely used method, and newer scientific approaches are needed. To develop a more objective and efficient tool for discriminating herbal origins, particularly Korean and Chinese, we employed a nuclear magnetic resonance (NMR)-based metabolomics approach combined with an orthogonal projections to latent structure-discriminant analysis (OPLS-DA) multivariate analysis. We first analyzed the constituent metabolites of Scutellaria baicalensis through NMR studies. Subsequent holistic data analysis with OPLS-DA yielded a statistical model that could cleanly discriminate between the sample groups even in the presence of large structured noise. An analysis of the statistical total correlation spectroscopy (STOCSY) spectrum identified citric acid and arginine as the key discriminating metabolites for Korean and Chinese samples. As a validation of the discrimination model, we performed blind prediction tests of sample origins using an external test set. Our model correctly predicted the origins of all of the 11 test samples, demonstrating its robustness. We tested the wider applicability of the developed method with three additional herbal medicines from Korea and China and obtained very high prediction accuracy. The solid discriminatory power and statistical validity of our method suggest its general applicability for determining the origins of herbal medicines.

Inositol 1,4,5-trisphosphate receptor (IP(3)R) is a major intracellular Ca(2+) channel, modulated by many factors in the cytosolic and lumenal compartments. Compared with cytosolic control, lumenal-side regulation has been much less studied, and some of its mechanistic aspects have been controversial. Of particular interest with regard to lumenal regulation are whether it involves direct interactions between IP(3)R and the regulators, and whether it involves conformational changes of the lumenal regions of IP(3)R. To understand these lumenal-side regulation mechanisms, we studied the effects of two important lumenal regulatory factors, the redox potential and Ca(2+), on the L3-1 lumenal loop region of IP(3)R. The redox potential exerted direct and significant effects on the conformation of the loop region. By sharp contrast, Ca(2+) showed little effect on the L3-1 conformation, suggesting that the regulation of Ca(2+) is indirect or involves other receptor regions. GSH/oxidized glutathione-mediated oxidation introduced a unique intramolecular disulfide bond between Cys(34) and Cys(42). A variety of NMR experiments revealed that oxidation also induces localized helical characteristics in the Cys(34)-Cys(42) region. Dynamics studies also showed reduced motions in the region upon oxidation, consistent with the conformational changes. The results raise the interesting possibility that Cys(34) and Cys(42) may act together as a reduction sensor, and that Cys(65) may function as an oxidation sensor. Overall, our studies suggest that the redox potential and Ca(2+) can regulate IP(3)R through totally different mechanisms: Ca(2+) by the indirect effect and the redox potential by direct action causing conformational changes.

Agro-herbal materials vary in prices and qualities depending on the origin and age and the differentiation is both scientific and public health issue. Here, we describe a metabolomics approach used to discriminate ginseng roots from different sources. Six different types of ginseng roots from China and Korea were analyzed by NMR-based metabolomics. Chinese Dangsam showed prominent differences and was easily differentiated. The difference was mainly due to the large signals in the sugar region. We further analyzed the metabolomics results in subgroups. Jeonra (Korean), Choongcheong (Korean), and Chinese ginseng in subgroup 1 could be easily differentiated by the first two principal components. The loading plot for PC1 showed that the Jeonra and Chinese ginseng roots were mainly separated by sugar signals and methyl signals but that they were reverse-correlated. A diffusion-ordered spectroscopy (DOSY) analysis showed that the methyl signals are from high molecular weight compounds and that the sugar signals are either from oligosaccharides or ginsenosides. In subgroup 2, composed of Korean Choongcheong ginseng at different ages, we were able to see age-dependent transitions in the score plot. We believe our approach can be applied to detecting the adulteration of ginseng root powders and other herbal products from different origins.

Chromogranin-derived peptides have important and varied biological activities. They affect a wide spectrum of targets such as fungal membranes, blood vessels, myocardial cells, and pancreatic cells. Despite the biological significance and the diverse activities, the molecular mechanisms of the interactions between the peptides and the target proteins have not been well understood. Here, we studied the interaction between a chromogranin A–derived peptide (CGA40–65) and its target protein, calmodulin, with NMR spectroscopy. Calmodulin was easily prepared with standard recombinant technology, but CGA40–65 posed challenges requiring multistep procedures. The recombinantly produced peptide retained the calmodulin-binding property of the full-length CGA, as shown by the HSQC binding experiment. By applying resonance assignments, we identified the residues in calmodulin involved in the CGA40–65 binding. We also found that the peak changes are close to those exhibited by the peptides having the wrap-around binding mechanism. Further analysis revealed that the CGA40–65-induced changes are more similar to those by CaMKIp peptide than those by smMLCKp peptide among the wrap-around binding peptides, suggesting that CGA40-65 can be categorized as a CaMKIp-like peptide. Our report is the first residue-resolution mechanistic study involving chromogranin peptides and their target proteins. Our approaches should be applicable to interaction studies involving other chromogranin-derived peptides and their cellular target proteins. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.

The preparation of nanocrystalline (Ti, M)(CN)–Ni and (Ti,M1, M2)(CN)–Ni powders from various mixtures of oxides is described. The method involved mechanical alloying, carbo-thermal reduction and nitridation. The resulting powders were solid–solution agglomerates with a crystallites size of ∼30 nm. The powders were chemically pure and had low oxygen content compared to commercial micron grade materials.

Metabolic surgery has been shown to provide better glycemic control for type 2 diabetes than conventional therapies. Still, the outcomes of the surgery are variable, and prognostic markers reflecting the metabolic changes by the surgery are yet to be established. NMR-based plasma metabolomics followed by multivariate regression was used to test the correlation between the metabolomic profile at 7-days after surgery and glycated hemoglobin (HbA1c) levels at 3-months (and up to 12 months with less patients), and to identify the relevant markers. Metabolomic profiles at 7-days could differentiate the patients according to the HbA1c improvement status at 3-months. The HbA1c values were predicted based on the metabolomics profile with partial least square regression, and found to be correlated with the observed values. Metabolite analysis suggested that 3-Hydroxybutyrate (3-HB) and glucose contributes to this prediction, and the [3-HB]/[glucose] exhibited a modest to good correlation with the HbA1c level at 3-months. The prediction of 3-month HbA1c using 7-day metabolomic profile and the suggested new criterion [3-HB]/[glucose] could augment current prognostic modalities and help clinicians decide if drug therapy is necessary.

This paper presents the fabrication and electrical characteristics of the Integrated Field Emission Microsource (IFEMS) with multiple gates. The molybdenum field emission tip was made by filling cusp-like mold formed when a conformal film was deposited on the hole-trench. Each field emitter has a 1.8 μm-diameter extraction gate and a 1.4 μm-diameter focusing gate. To make a path for the emitted electrons, silicon bulk was etched anisotropically in KOH and EDP(Ethylene-Diamine Pyrocatechol) solution successively. The emission characteristics were measured and the influence of the focusing gate has been analyzed.

We have constructed microcolumn system that can overcome the limitation of current e-beam lithography technology and tested them through experiments. Electron-optical lenses consist of multiple electrodes. Silicon electrodes have been fabricated by micromachining technology and assembled with Pyrex glass by anodic bonding. Electron-optical lens was equipped in UHV(Ultra High Vacuum) chamber. We have observed the emission characteristics of electrons from STM(Scanning Tunneling Microscope) tip and performed lithography with focused electrons. PMMA(poly-methylmethacrylate) was used for e-beam resist and 0.13 μm isolated line was delineated on PMMA(poly-methylmethacrylate) with the microcolumn system.

Detecting possible modifications of therapeutic proteins is a critical element of the quality control of protein drugs. Typically, a number of techniques are used to evaluate different modifications of therapeutic protein formulations. Using heteronuclear NMR spectroscopy, we show that the difference between various insulin formulations can be detected "as is" with little pretreatment and quickly. As an application to the quality control of insulin formulations, the NMR approach was compared with four different analytical methods: with reverse phase high pressure liquid chromatography (HPLC) (for mutations), with size exclusion chromatography (for oligomerization), with electrophoresis (for denaturation), and with mass spectrometry (for deamidation). All of the results showed that this single NMR method can provide the specific signatures for each modification and information that is at least equivalent to that offered by the conventional analytical methods. Importantly, NMR could yield information at each amino acid residue level which no other technique provided. The suggested NMR method, then, can be considered to be a facile and effective means of evaluating therapeutic protein formulations in a multifaceted way.

A numerical study of conjugate heat transfer and particle transport has been carried out for the outside vapor deposition process. A buoyant jet flow impinging on a two-layered cylinder has been analyzed including heat conduction occurring through the two-layered cylinder, which consists of the original target rod and the deposited porous layers. Temperature and flow fields have been obtained by an iterative method, and thermophoretic particle deposition has been studied. Of particular interest are the effects of the thickness of deposited layers, the torch speed, the rotation speed of the cylinder, and the distance between the torch and the cylinder on the heat transfer and particle deposition. Effects of variable properties and tube rotation are also included.

This paper presents a method for improvements of radio frequency (RF) microelectromechanical systems (MEMS) switch which was previously reported at MEMS 2008 [1] and introduces a single-pole twelve-throw (SP12T) switch based on improved switch. The proposed switch was driven by a double stop (DS) comb drive, with a lateral resistive contact. Additionally, the proposed switch was designed to be bidirectionally actuated. A forward actuation connects between signal lines and contact part, and the output becomes on-state. A reverse actuation connects between ground lines and contact part, and the output becomes off-state. This can make ground lines have same bias, and improve the RF characteristics. The 2-stage cascade type SP12T switch was developed based on an arrangement of the proposed RF MEMS switches.

Ganoderma lucidum is a widely used and high-value medicinal natural product. Correct identification of its cultivation source is important for proper quality assurance, but is so far mostly dependent on subjective morphological examinations.To develop an efficient way of discriminating the cultivation sources of Ganoderma lucidum, particularly those from Korea and China, the two major sources of the mushroom using NMR-based metabolomic differentiation.Ganoderma lucidum samples were collected from Korea (26 samples) and China (20 samples), and their NMR spectra were obtained. The raw data were processed, and analysed using multivariate statistical analysis.Although conventional principal component analysis showed some overlaps, orthogonal projections to latent structure discriminant analysis (OPLS-DA) provided clean distinction between samples from the two countries. Contributing signals were also identified using S-plot, and further verified with independent t-test. Final validation of the model was obtained using prediction test of the unknowns, where the model predicted all of the 14 test samples correctly. Distinction between the cultivation sources within China was also established.The easiness and transferability of our NMR-based approach should contribute to addressing an important aspect of quality control process of Ganoderma lucidum. We believe the method can be easily applied to other herbal medical products.

Inositol 1,4,5-trisphosphate receptor (IP(3)R) is a major intracellular Ca(2+) channel, modulated by many factors in the cytosolic and lumenal compartments. Compared with cytosolic control, lumenal-side regulation has been much less studied, and some of its mechanistic aspects have been controversial. Of particular interest with regard to lumenal regulation are whether it involves direct interactions between IP(3)R and the regulators, and whether it involves conformational changes of the lumenal regions of IP(3)R. To understand these lumenal-side regulation mechanisms, we studied the effects of two important lumenal regulatory factors, the redox potential and Ca(2+), on the L3-1 lumenal loop region of IP(3)R. The redox potential exerted direct and significant effects on the conformation of the loop region. By sharp contrast, Ca(2+) showed little effect on the L3-1 conformation, suggesting that the regulation of Ca(2+) is indirect or involves other receptor regions. GSH/oxidized glutathione-mediated oxidation introduced a unique intramolecular disulfide bond between Cys(34) and Cys(42). A variety of NMR experiments revealed that oxidation also induces localized helical characteristics in the Cys(34)-Cys(42) region. Dynamics studies also showed reduced motions in the region upon oxidation, consistent with the conformational changes. The results raise the interesting possibility that Cys(34) and Cys(42) may act together as a reduction sensor, and that Cys(65) may function as an oxidation sensor. Overall, our studies suggest that the redox potential and Ca(2+) can regulate IP(3)R through totally different mechanisms: Ca(2+) by the indirect effect and the redox potential by direct action causing conformational changes.

This paper presents the RF characteristics of the RF MEMS switch as the silicon substrate resistivity. The larger the resistivity of silicon substrate is, the larger the insertion loss of the RF MEMS switch is. When the RF MEMS switch is fabricated with the single crystalline silicon, the RF characteristics are changed by resistivity of silicon. It is necessary to study the change of RF characteristics as the substrate resistivity. The RF characteristics were simulated with different resistivity of silicon substrate. The RF MEMS switches were fabricated on each substrate with different resistivity. The RF MEMS switch was fabricated with the resistivity of 10 ohm-cm, the insertion loss of that is about 0.2 dB at 6 GHz. And the RF MEMS switch was fabricated with the resistivity of 500 Ohm-cm, the insertion loss of that is about 0.6 dB at 6 GHz.

The SH3 domain is a versatile protein interaction motif that generally recognizes proline rich sequences (PRS). Recently, it has been shown that some SH3 domains in the endocytotic pathway can bind to ubiquitin. Moreover, Phe73 in the SH3 domain has been proposed to be an important determinant of the interaction, as the SH3 domains having Tyr73, either naturally or by mutation, failed to bind. Since SH3 domains are also important in immune receptor signaling, we investigated the interactions between immunologically relevant SH3 domains and ubiquitin. We observed that some of these SH3 domains can also bind to ubiquitin. Interestingly, we found that Nck2-SH3-3 bound to ubiquitin despite its Tyr at residue 73 (Tyr56 in our actual construct), but that CD2BP1-SH3 failed to bind, even though it has Phe at an equivalent position. Through detailed NMR binding studies on SH3 domains with Phes and Tyrs at the 73 position, we found that the two types of SH3 domains exhibit mechanistic differences in ubiquitin binding. We showed that the relative contribution of each binding sub-region in both SH3 domains and ubiquitin is quite different in the two binding modes. Such results raise the possibility that the mechanistic variety of these immunologically relevant SH3 domains might contribute to their functional diversity.

The inositol 1,4,5-trisphosphate receptor (IP3R) is a membrane channel that conducts calcium ions from the intracellular calcium stores. Despite a wealth of information on the cytoplasmic regulation of the IP3R, little is known about its regulation on the luminal side of the calcium stores. Here, we report studies on the IP3R intraluminal loop L3-2 and a conserved N-terminal region of chromogranin B. The IP3R loop is an important part of the channel's pore-forming region, and the chromogranin peptide has been shown to competitively inhibit calcium signaling by IP3R. Using the NMR titration approach, we showed that a part of the L3-2 is involved in a specific interaction with the chromogranin B peptide. Further NMR resonance assignments revealed that the 14th-20th residues of L3-2 are the keys to the binding to the chromogranin B peptide. Through detailed analysis of the data, we suggest a mechanism of IP3R regulation by chromogranin B involving conformational exchanges of the L3-2 region. Our report presents the findings of the first study on the interaction between the luminal loop of the IP3 receptor and its regulator at residue-resolution. The approaches described here should help to guide further studies on the interactions between the IP3R and other luminal side regulators.

The nonstoichiometry (δ) and phase stability range of (Mg x Fe 1-x ) 3-δ O 4 has been determine by a coulometric titration method as a function of oxygen activity and the Mg content (x) at 1000°C. The nonstoichiometry can best be explained in terms of Frenkel disorder.

Phase stability regions in Mg-Fe-O system were investigated against temperature, cationic composition, and oxygen partial pressure using electrical conductivity and thermoelectric power measurements. Using these results, phase diagrams of the first kind (i.e., Po 2 vs. T) for fixed compositions and the second kind (i.e., composition vs. Po 2 ) at fixed temperatures were constructed extensively.

We constructed a scanning tunneling microscope aligned field emission (SAFE) source by using silicon micro-fabricated electrostatic lenses. The system consists of an STM aligned field emitter, 5μm extractor, 100μm accelerator, beam dump, quadrupole deflector and einzel lens. The microlenses were made by using silicon processing techniques. The system can be operated from 200 to 2 kV, resulting in a beam current of tens of nA and with the diameter of ∼ 0.1 μm when a sample was placed less than 2 mm away from the exiting einzel lens. In order to measure the spherical and chromatic aberrations, a detector and cylindrical electron energy analyzer were attached to the micro-column.

e15525 Background: The association between ovarian cancer and endometriosis has not been well established in previous studies. We investigated the impact of endometriosis on the development of ovar...

7547 Background: Sorafenib and erlotinib are potent, orally administered receptor tyrosine kinase inhibitors with antiproliferative and antiangiogenic activities. Given their inhibitory target prof...

5551 Background: We evaluated the prognostic significance of excision repair cross-complementation group 1 protein (ERCC1), thymidylate synthase (TS), and Bax in patients with nasopharyngeal cancer...